Treatment of advanced nasopharyngeal cancer using low- or high-dose concurrent chemoradiotherapy with intensity-modulated radiotherapy: A propensity score-matched, nationwide, population-based cohort study

Publication date: Available online 22 December 2017
Source:Radiotherapy and Oncology
Author(s): Tsung-Ming Chen, Kuan-Chou Lin, Kevin Sheng-Po Yuan, Chia-Lun Chang, Jyh-Ming Chow, Szu-Yuan Wu
BackgroundNo large-scale, head-to-head, phase III, randomized, controlled trial with an adequate sample size has investigated the effect of concurrent low-dose (LD) or high-dose (HD) cisplatin with radiotherapy on nasopharyngeal cancer (NPC). Thus, we conducted a propensity-score-matched, nationwide, population-based cohort study in Taiwan to investigate the outcomes of LD-concurrent chemoradiotherapy (CCRT) or HD-CCRT with intensity-modulated radiotherapy (IMRT) in patients with advanced NPC.MethodsIn this study, patients were categorized into 2 groups according to their chemotherapy regimen: HD-CCRT and LD-CCRT groups.ResultsWe enrolled 1968 patients (328 and 1640 in the LD-CCRT and HD-CCRT groups, respectively) who had received CCRT with IMRT. According to both univariate and multivariate Cox regression analyses, a hazard ratio (95% confidence interval) of 0.75 (0.54–1.06, P = .103) was derived for the HD-CCRT group.ConclusionLD-CCRT or HD-CCRT with IMRT can be a standard treatment that can prolong the survival of patients with advanced NPC.



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Removal of thyroid remnant for cancer in the previously operated central neck

Publication date: Available online 22 December 2017
Source:Operative Techniques in Otolaryngology-Head and Neck Surgery
Author(s): Vaninder K Dhillon, Ralph P Tufano
Reoperative central neck dissection requires a concise set of steps to complete a comprehensive dissection of recurrent lymphadenopathy seen in thyroid cancer. The main considerations take into account the recurrent laryngeal nerve and the parathyroid glands. This chapter specifies those steps from a preoperative evaluation to the pearls during dissection to ensure a complete reoperative dissection that removes all residual thyroid tissue and lymphadenopathy while ensuring the best outcomes.



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Recurrent laryngeal nerve preservation in thyroid cancer involving the ligament of berry

Publication date: Available online 22 December 2017
Source:Operative Techniques in Otolaryngology-Head and Neck Surgery
Author(s): Nathan W. Hales, Dipti Kamani, GregoryW. Randolph
The ligament of Berry is a dense consolidation of pretracheal vascular fascia or suspensory ligament which anchors the thyroid to the trachea and is located medial and deep to the tubercle of Zuckerkandl. The ligament of Berry is closely related to the distal 2cm of the extralaryngeal course of the recurrent laryngeal nerve and to the superior parathyroid gland. When thyroid cancer is present in the ligament of Berry, proper preoperative imaging, meticulous dissection with extra caution in the area of the ligament of Berry and use of intraoperative nerve monitoring are helpful tools in preservation of recurrent laryngeal nerve. Additionally, when thyroid cancer is preoperatively suspected to involve ligament of Berry, proper preoperative counseling, detailed consent, as well as communication regarding accurate patient expectations are essential.



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A rare cause of neonatal persistent jaundice

Description

A 22-year-old gravida 2, para 1 (G2P1) woman with immunoglobulin anti-D prophylaxis, insulin-treated gestational diabetes and first-trimester cytomegalovirus (CMV) infection vaginally delivered a 39-week boy weighing 3720 g (90th centile) and with Apgar scores of 8 and 10 at 1 and 5 min. Prenatal ultrasonographic assessment throughout gestation was normal. Nursery stay was uneventful. He was discharged on day 2, with a normal examination, except for the appearance of jaundice, with a transcutaneous bilirubin of 248 µmol/L (cut-off 250 µmol/L), not meeting the criteria for phototherapy. A follow-up clinic on day 4, arranged for bilirubin measurement and CMV testing, surprisingly revealed poor general appearance, lethargy, very icteric skin and a minor weight loss (9% of birth weight). Both liver and splenic edges were palpable. Vital signs were normal. Blood routine showed haemoglobin of 19 g/dL, haematocrit of 58%, white blood cells 11.6x10⁹/L and platelet count 128x10⁹/L. Biochemistry revealed total serum bilirubin...

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Maxillary chondrosarcoma mimicking torus palatinus

Description 

An 88-year-old man was referred to the head and neck surgery clinic for investigation of a painless hard palate lesion. The mass had been present for several months and was identified incidentally by the general practitioner. There were no oral or sinonasal symptoms. On examination, a 3x2 cm hard palatal swelling, covered by normal mucosa and resembling a torus palatinus was identified (figure 1). Flexible nasal endoscopy revealed the tumour to involve the floor of the nasal cavity bilaterally, displacing the inferior nasal turbinates. Examination of the neck was normal.

Figure 1

Midline palatal swelling covered by mucosa.

A biopsy was taken, and histological analysis described a welldifferentiated cartilaginous lesion consistent with a grade 1 chondrosarcoma. A CT scan was performed (figure 2). The regional head and neck and regional sarcoma multidisciplinary team meetings recommended surgical management. The patient underwent...

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Intractable hyperemesis gravidarum in a patient with type 1 diabetes

Hyperemesis gravidarum is not uncommon. Its pathogenies is multifactorial but not fully understood. We present a case of a middle class, Caucasian pregnant woman aged 24 years with coexisting type 1 diabetes, who had severe hyperemesis gravidarum from the sixth week of pregnancy and was resistant to all standard and off-the-label treatments raising questions about the pathogenesis of hyperemesis gravidarum. She was managed with a multidisciplinary approach and was supported with total parenteral nutrition till she had an emergency caesarean section in the 29th week of pregnancy. Her vomiting stopped as soon as a small for gestational age but otherwise healthy male baby was delivered.

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Intradural lumbar disc herniation detected by 3D CISS MRI

A 73-year-old man who presented with right lumbosciatic pain underwent a neurosurgical operation for a voluminous L2–L3 disc herniation, seen on conventional MRI images. No disc herniation was identified in the epidural space during the surgery. Just after the operation, the patient started to present pain in the left L3 territory and was not able to walk any more. A second MRI including three-dimensional (3D) high-resolution constructive interference in steady state (CISS) sequence showed that the voluminous L2–L3 disc split the posterior longitudinal ligament and the anterior dura mater, extended intradurally and compressed the cauda equina to the right. The patient underwent a second surgery, which permitted to cure the symptoms. 3D high-resolution CISS should be considered to accurately depict intradural disc herniation in order to optimally guide the surgical approach.

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Shah-Waardenburg syndrome: a case highlighting the importance of a holistic approach to assessing a child

We present the case of a 45-day-old child with the chief complaint of failure to pass stools for 10 days. After initial investigation, the patient was found to have Hirschsprung's disease. However, with further examination and analysis, the extremely rare diagnosis of type 4 Waardenburg syndrome was made (also known as Shah-Waardenburg syndrome or Waardenburg-Hirschsprung's disease).

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Solid pseudopapillary tumour (Frantzs tumour) of the pancreas in childhood: successful management of late liver metastases with sunitinib and chemoembolisation

The patient is a girl aged 17 years who originally presented at age 11 years with a solid pseudopapillary tumour (SPT) in the head of the pancreas treated by an R0 pylorus-preserving Whipple procedure. The patient underwent surveillance CT every 3 months for the first year followed by MRI every 6 months. She was noted to have a new liver lesion in Couinaud segment VI highly suspicious for metastasis at 30 months. Liver wedge biopsy confirmed metastatic SPT. Two months later two new lesions were noted in Couinaud segment VII. The family preferred medical management to surgery resulting in a treatment combination of the tyrosine kinase inhibitor sunitinib and hepatic artery embolisation. The patient developed a hepatic abscess following embolisation but recovered with antibiotics. The patient has subsequently been followed with serial MRIs every 3 months, and 20 months following chemoembolisation, she has no evidence of recurrence of the metastases.

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Unusual case of anxiety: trichloroethylene neurotoxicity

I present an uncommon case of recurrent, intractable anxiety that was presented acutely and slowly evolved into a chronic debilitating condition. A young previously fit and healthy 24-year-old patient presents with somewhat atypical symptoms of anxiety. Full medical work-up including examination, blood, ECG electrocardiogram, electroencephalogram and CT of the head was unremarkable. When the history was explored in detail, it was revealed he worked in the navy and was exposed to a neurotoxic solvent, trichloroethylene. This case highlights the importance of eliciting a detailed occupational history, particularly paying attention to patient demographics such as occupation and presenting symptoms that do not readily fit into diagnostic criteria.

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Cutaneous infection with paucibacillary Mycobacterium tuberculosis treated successfully with a modified antituberculous drug regimen

Tuberculosis is a serious infection that is increasing in prevalence, affecting many people worldwide. The diagnosis of cutaneous tuberculosis is challenging and requires the correlation of clinical findings with often inconclusive diagnostic testing. Extrapulmonary tuberculosis comprises approximately 10% of all cases of tuberculosis, and cutaneous tuberculosis makes up only a small proportion of these cases. Discussed here is the case of a 61-year-old immunocompetent female with a large cutaneous lesion on her index finger secondary to Mycobacterium tuberculosis. Tissue cultures taken at biopsy were negative; however, empiric antimycobacterial therapy was initiated. The initial regimen was not tolerated, and antituberculous therapy was substituted for moxifloxacin and clarithromycin. The lesion improved significantly with a concurrent improvement in function.

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Short-course high-dose ibuprofen causing both early and delayed jejunal perforations in a non-smoking man

Description

A 48-year-old non-smoking man underwent laparotomy for peritonitis immediately after taking ibuprofen 800 mg 6 hourly for 14 days for back pain. His only other medication was long-term omeprazole 20 mg per day. At operation he had three separate perforations in his proximal jejunum. Fifteen centimetres of jejunum were resected with primary anastomosis. Histology showed focal mucosal ischaemic changes with normal mucosa between. There was no vasculitis. The perforations were attributed to ibuprofen intake. He made an uneventful recovery and was instructed to refrain from non-steroidal anti-inflammatory drug (NSAID) intake.

He was readmitted 5 months later with abdominal pain. He had continued omeprazole but had taken no further NSAID. CT showed extensive free intra-abdominal fluid with free gas adjacent to his proximal jejunum (figure 1), indicating a further perforation. This was confirmed at laparotomy when a 5 mm perforated ulcer was found in his proximal jejunum (figure...

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Oyster-related tenosynovitis: a rare case of Mycobacterium szulgai in the immunocompromised

A 66-year-old man with a history of renal transplant on chronic immunosuppression presented to his primary care physician with a swollen right index finger. On examination, mild swelling was present. Conservative management failed and initial plain films were negative. Corticosteroid injection was performed by orthopaedics, but symptoms recurred several months later and an MRI showed flexor digitorum tenosynovitis and abscesses of the superficialis and profundus tendons. A flexor tenolysis was performed with cultures positive for Mycobacterium szulgai, a rare, non-tuberculous mycobacterial infection. Treatment was initiated with moxifloxacin, ethambutol and azithromycin daily for nearly 4 months. Repeat MRI 3 months after completion of antibiotics showed near resolution of the tenosynovitis.

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HHV-8-associated haemophagocytic lymphohistiocytosis in a patient with advanced AIDS

We present a patient with advanced AIDS admitted with recurrent shock of unclear aetiology, fevers, altered mental status and refractory cytopenias. His case posed a diagnostic challenge because evaluation of septic shock in the setting of advanced AIDS requires a time-consuming work-up for broad infectious aetiologies that can delay consideration of other diagnoses, including primary or secondary haemophagocytic lymphohistiocytosis (HLH). After this patient did not improve with supportive care and empiric antimicrobials, there was concern for HLH given that he met ≥5 of the HLH consortium criteria. He underwent bone marrow biopsy, which was non-diagnostic. Empiric therapy for HLH was initiated, but unfortunately, the patient died. Autopsy revealed extensive haemophagocytosis in the spleen, bone marrow and liver, confirming the diagnosis of HLH. Postmortem, his soluble CD-25 returned 18 890 pg/mL (<1033 pg/mL), and his serum HHV-8 PCR resulted positive. The diagnosis was HLH secondary to Human Herpes Virus 8 (HHV-8) in a patient with advanced AIDS.

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Chickenpox: an ageless disease

A 97-year-old woman presented with 4-day history of vesicular rash, initially at the feet but then spread up to the thighs bilaterally, abdomen and trunk. The initial differentials included bullous pemphigus and cellulitis by the emergency department. She was then managed as bullous pemphigus by the acute medical team and started on high-dose steroids, with no other differentials considered. When her care was taken over by the general medical team, varicella zoster virus (VZV) infection was suspected. After confirmation by the dermatology team regarding the clinical diagnosis and the positive VZV DNA swabs, she was started on acyclovir.

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Osteoid bezoar: a rare case causing small bowel obstruction

Acute intestinal obstruction due to foreign bodies or bezoar is a rare occurrence in an adult. We report an unusual case of a 27-year-old male patient with no previous history of abdominal surgery or other medical disease, who presented with an acute episode of intestinal obstruction due to ingestion of a bone piece which was managed surgically by enterotomy, and the patient had an uneventful postoperative course. He was advised regular follow-up once in 2 weeks initially and once a month subsequently. He had no problems at the end of 6 months.

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Syndrome of X linked intellectual disability, epilepsy, progressive brain atrophy and large head associated with SLC9A6 mutation

SLC9A6 gene encodes for a sodium/hydrogen exchanger-6 protein mainly involved in endosomal trafficking and maintaining intraluminal pH. Loss of function mutations in SLC9A6 gene in children has been associated with Christianson syndrome and autism spectrum disorder. We describe a 3-year-old boy with intellectual disability, infantile-onset drug-refractory epilepsy, progressive brain atrophy and large head with a novel missense hemizygous mutation in exon 16 of the SLC9A6 gene on chromosome X. Presence of large head, early developmental regression and progressive cerebral atrophy expand the phenotypic spectrum of SLC9A6 mutations. Our case also highlights the importance of genetic testing in children with unexplained intellectual disability, epilepsy and neurodevelopmental impairments.

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Idiopathic bilateral hypertrophic olivary degeneration

Description

A 55-year-old man presented with involuntary movements of the tongue and soft palate associated with unsteadiness in walking for a period of 3 months. The patient did not complain of ear clicking. Examination revealed palatal myoclonus, tongue fasciculation and ataxic gait. MRI of the brain showed increased T2 and Fluid Attenuation Inversion recovery (FLAIR) signal intensities in the bilateral inferior olivary complex without diffusion restriction (figure 1). Midbrain, pons, and cerebral and cerebellar parenchyma were normal (figure 2). Imaging features were consistent with bilateral hypertrophic olivary degeneration. Hypertrophic olivary degeneration is a unique type of trans-synaptic neuronal degeneration caused by damage to the dentatorubral pathway or the triangle of Guillain and Mollaret (figure 3). Focal lesions like infarction, haemorrhage, demyelination  and trauma involving this neuronal pathway lead to interruption, and following sequential pathological changes are described (table 1).1

Figure 1

Coronal T2 (A), axial T2 (B),...

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Contemporary non-surgical approach for faecal diversion in a case of Fourniers gangrene

Fournier's gangrene is a fatal necrotising fasciitis of the perineum, genitals and lower abdomen. Patients often need an aggressive surgical debridement, and in few cases, a diverting colostomy. We report the case of a 70-year-old man with multiple comorbidities diagnosed with Fournier's gangrene, who underwent debridement and had a wound complication due to faecal contamination. A novel, self-retaining rectal device was used to perform faecal diversion, which subsequently showed wound healing within a week, hence avoiding the need of a colostomy.

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Variant of Lemierres syndrome with internal jugular vein aneurysm

Internal jugular vein (IJV) aneurysm is a rare entity, and a thrombosed aneurysm poses diagnostic and management challenges. We came across a 53-year-old woman who presented with fever, vomiting and right neck swelling for a week. Laboratory investigations showed neutrophilic leucocytosis, raised acute phase reactant and blood culture yielded Klebsiella pneumoniae. Ultrasound and contrast-enhanced CT neck revealed a large fusiform aneurysm of the right IJV with filling defect extending from the aneurysm into the right transverse sinus. There was a cavity at the right lower third molar tooth. MRI confirmed the findings with additional enhancing focus at right lower periodontal region. The swelling reduced after 2 weeks of medical therapy, and follow-up imaging 4 months later showed complete resolution of the aneurysm with residual thrombosis. After extensive workup, dental infection remains the only identifiable primary source leading to thrombophlebitis of the right IJV and subsequent sequelae.

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Correction: Gangrenous digital infarcts in a severe case of cutaneous polyarteritis nodosa

The correct order of authors is as follows:

Hamzah Mahmood-Rao, Nirav Gandhi, Tina Ding

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Double hit! A unique case of resistant hypertension

A middle-aged woman with obesity, hyperlipidaemia and diet-controlled diabetes was referred for resistant hypertension. Her blood pressure (BP) was uncontrolled on five medications, including a diuretic. Physical exam revealed a systolic ejection murmur, and ECHO demonstrated moderate hypertrophy. Laboratory examination revealed elevated aldosterone level (20.7 ng/dL) and elevated aldosterone:renin ratio (41.4 (ng/dL)/(ng/mL/h)), meeting criteria for primary aldosteronism (PA), and confirmed by saline infusion testing. CT scan of the adrenals was non-localising. Adrenal venous sampling confirmed bilateral idiopathic adrenal hyperplasia. Concurrent primary hyperparathyroidism was demonstrated by elevated calcium and parathyroid hormone levels and localised by sestamibi scan. Idiopathic adrenal hyperplasia was treated medically with spironolactone. Her BP remained elevated until postparathyroidectomy. Evidence shows that a hyperfunctioning parathyroid gland may contribute to maintaining hyperaldosteronism in PA making this bidirectional link unique. The significance of this case is in the potential for further understanding of the pathophysiology of common causes of secondary hypertension.

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Epstein–Barr virus exanthem in an adult patient with myelodysplastic syndrome

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Ischaemic ulcers on the toes secondary to Raynaud phenomenon in a patient with systemic sclerosis successfully treated with botulinum toxin

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Morphologic and mechanical properties of blends from recycled acrylonitrile-butadiene-styrene and high-impact polystyrene

Publication date: 17 January 2018
Source:Polymer, Volume 135
Author(s): Denise Hirayama, Clodoaldo Saron
Waste electrical and electronic equipment (WEEE) have attracted attention due to their high pollutant potential and increasing volume produced in recent years as function of the modernization and continuum substitution of the current equipment that quickly become obsolete. Among polymeric materials that make up the WEEE, acrylonitrile-butadiene-styrene (ABS) and high-impact polystyrene (HIPS) copolymers are the most important materials. However, it is not always possible the complete segregation of ABS and HIPS during the processes for mechanical recycling of these polymers. Thus, the formation of ABS/HIPS blends is often unavoidable. In this report, the relationship between morphology and mechanical/rheological properties of ABS/HIPS blends produced from WEEE recycling was investigated. Although the component polystyrene (PS) and polybutadiene (PB) are present in the composition of both ABS and HIPS, the blends ABS/HIPS are immiscible, showing complex morphology that directly affect the mechanical and rheological behavior of the material. On the other hand, the production of the ABS/HIPS blends is an interesting alternative for properties control of the recycled polymers from WEEE.

Graphical abstract

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Nano-mechanical properties of interphases in dynamically vulcanized thermoplastic alloy

Publication date: 17 January 2018
Source:Polymer, Volume 135
Author(s): Hailu G. Kassa, Johan Stuyver, Anton-Jan Bons, David B. Haviland, Per-Anders Thorén, Riccardo Borgani, Daniel Forchheimer, Philippe Leclère
We present a high-resolution study of the viscoelastic response of a thermoplastic alloy using a multifrequency method called intermodulation atomic force microscopy. We quantitatively characterize the response in terms of calibrated dynamic force quadrature curves, showing the conservative and dissipative forces at each image pixel as functions of the oscillation amplitude for industrial polymer blends.

Graphical abstract

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Putative role of attractive and repulsive forces in the glass transition

Publication date: 17 January 2018
Source:Polymer, Volume 135
Author(s): Isaac C. Sanchez, Sean P. O'Keefe, Jeffrey P. Thompson
At a given temperature a balance between repulsive and attractive molecular forces determines liquid density. As temperature is lowered, attractive forces increase, but eventually saturate and asymptote to a near fixed value. At saturation, the attractive/repulsive force balance stabilizes the liquid density, which thereafter becomes effectively temperature independent. Configurational entropy also saturates, but at a much lower temperature. Once entropy begins to saturate, it converges to zero at absolute zero. There is no second order phase transition nor is there a divergent temperature above absolute zero predicted for glass relaxation phenomena. Using a phenomenological argument, it is shown that the relaxation time for volume relaxation varies inversely with configurational entropy. Stoichiometric electron density is proposed as a metric for repulsive force strength, which was determined at Tg and averaged 0.61±0.03 mol/cc for 15 polymers that contain oxygen and 0.53±0.02 mol/cc for 7 hydrocarbon polymers. Qualitatively, similar polymer liquids that pack to higher electron densities at a given temperature are expected to experience a glass transition earlier as temperature is lowered. For certain polymer types, the glass transition appears to be an isoelectronic state.

Graphical abstract

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Performance of high lignin content cellulose nanocrystals in poly(lactic acid)

Publication date: 17 January 2018
Source:Polymer, Volume 135
Author(s): Liqing Wei, Umesh P. Agarwal, Laurent Matuana, Ronald C. Sabo, Nicole M. Stark
High lignin-containing cellulose nanocrystals (HLCNCs) were successfully isolated from hydrothermally treated aspen fibers and freeze-dried and compounded with poly (lactic acid) (PLA) by extrusion and injection molding. As a comparison, PLA composites containing commercial lignin-coated CNCs (BLCNCs) were also produced. HLCNCs showed higher crystallinity, larger surface area, lower degree of agglomeration, and more hydrophobic surfaces compared to BLCNCs, as characterized by electron microscopy, surface area measurements, thermal analysis, spectroscopy and water contact angle measurements. The effect of lignin and CNC morphology on the mechanical, thermal and viscoelastic properties and CNCs/polymer interfacial adhesion of nanocomposites was investigated with tensile test, DSC and DMA. Compared to neat PLA, the Young's modulus, elongation to break, and toughness of PLA/2%HLCNCs were improved by 14, 77, and 30%, respectively. HLCNCs and BLCNCs act as nucleating fillers, increasing the degree of crystallinity (χc) of PLA in nanocomposites. The presence of lignin nanoparticles in the HLCNC increased the compatibility/adhesion between CNCs and polymer matrix which increased the storage modulus.

Graphical abstract

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Welcome to the first issue of polymer for 2018!

Publication date: 3 January 2018
Source:Polymer, Volume 134
Author(s): Leanne Mullen




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A drip-crosslinked tough hydrogel

Publication date: 17 January 2018
Source:Polymer, Volume 135
Author(s): Yu Zhang, You Yong, Duo An, Wei Song, Qingsheng Liu, Longhai Wang, Yehudah Pardo, Vanessa R. Kern, Paul H. Steen, Wei Hong, Zheng Liu, Minglin Ma
Hydrogels with good mechanical properties have received intense interests recently. Simplifying the method to prepare tough hydrogels and meantime incorporating additional properties such as anti-swelling, self-recovery, healing ability, facile processability, and recyclability will likely expand their applications significantly. Here we report a simple method to prepare tough hydrogels: dripping a carboxylated polyvinyl alcohol solution into an Al³⁺ crosslinking medium. The hydrogels became even tougher after equilibrium in DI water. These drip-crosslinked tough hydrogels exhibited anti-swelling, self-recovery, acid assisted healing and great processability, and could be recycled. Interestingly, by tuning the kinetics of dripping and crosslinking, we could make tough hydrogel particles with both conventional spherical shape and various other controllable, unusual shapes such as half-sphere, tear-drop, mushroom-like and rings. We also demonstrated the possibility of using electrospraying to mass-produce uniform, micron-sized tough hydrogels.

Graphical abstract

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Polyurethane-silica nanocomposites provided from perhydropolysilazane: Polymerization mechanism

Publication date: 17 January 2018
Source:Polymer, Volume 135
Author(s): Joo Yeon Lee, Reiko Saito
Polyhydroxyurethane-silica nanocomposites were synthesized with 2-ethyl-2-(((3-((2-(2-oxo-1,3-dioxolan-4-ly)ethyl)thio)propanoyl)oxy)methyl)propane-1,3-diylbis(3-((2-(2-oxo-1,3-dioxolan-4-yl)ethyl)thio)propanate), Tris-CC, and 1,3-diaminopropane in the presence of 5–30 wt% of perhydropolysilazane, PHPS, which is a precursor of silica, in one step. During the synthesis of nanocomposite, three reactions, which are formation of hydroxy group by ring opening polymerization of cyclic carbonate, conversion of PHPS into silica, and the formation of Si-O-C bond by reaction between hydroxy group formed by ring opening and SiH group of PHPS, were competitively proceeded. The competitive reaction mechanism for polyhydroxyurethane-silica nanocomposite was quantitatively analyzed by using propylene carbonate, PC, and propylamine as model compounds of Tris-CC and 1,3-diaminopropane by ¹H NMR. The hydroxy group of polyhydroxyurethane was preferentially formed compared to the conversion of PHPS into silica, then the Si-O-C bond was formed between polyhydroxyurethane and PHPS until 5 h. The formation rate of Si-O-C bond was governed by the formation rate of the hydroxy group of polyhydroxyurethane. On the other hand, the conversion of PHPS to silica was preferentially performed than the formation of hydroxy group of polyhydroxyurethane over 5 h. The hydroxy group of polyhydroxyurethane was more slowly formed than the conversion of PHPS to silica over 5 h. Less competitive reaction between polyhydroxyurethane and PHPS occurred, which lead to the less formation of Si-O-C bond.

Graphical abstract

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The nature of bonding matters: Benzoxazine based shape memory polymers

Publication date: 17 January 2018
Source:Polymer, Volume 135
Author(s): Hannes Schäfer, Andreas Hartwig, Katharina Koschek
A novel shape memory polymer is presented based on polybenzoxazine and poly(ε-caprolactone) (PCL). Polybenzoxazines with unbound and covalently incorporated PCL were prepared applying hydroxyl and tosyl terminated PCLs, respectively. Thermo-responsive and shape memory behavior with high shape fixity and recovery were demonstrated for samples containing a high ratio of covalently bonded PCL in a crosslinked benzoxazine structure. Samples with exclusively non-bonded PCL chains proved to be brittle, possessing a heterogeneous morphology and lacking shape memory properties. The type of bonding into benzoxazines network – covalent versus non-covalent bonding of PCL – strongly affects materials structure property relationship.

Graphical abstract

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Shear-induced precursors in polyethylene: An in-situ synchrotron radiation scanning X-ray microdiffraction study

Publication date: 17 January 2018
Source:Polymer, Volume 135
Author(s): Fengmei Su, Youxin Ji, Lingpu Meng, Jiarui Chang, Liang Chen, Liangbin Li
Localized shear flow was imposed by pulling glass fiber in polyethylene (PE) melt below and above its equilibrium melting point (141.6 °C). Immediately after the cessation of shear, the structure around the fiber was investigated with in-situ synchrotron radiation scanning X-ray microdiffraction (SR-μSXRD), which had spot area of 4.2 × 4.5 μm² and step size of 6 μm. Results indicate that crystalline precursors are induced below equilibrium melting point, as evidenced by the occurrence of crystalline diffractions. Whilst at temperature above equilibrium melting point, no crystalline diffraction is observed. SR-μSXRD measurements on the crystallization behaviors at 127 °C after shearing at 145 °C suggest that non-crystalline precursors are induced, which is supported by three evidences. (i) The occurrence of crystallization near the fiber surface implies shear-induced formation of precursors at 145 °C since the fiber has no ability to induce crystallization at quiescent condition; (ii) No crystalline diffraction is detected immediately after cessation of shear at 145 °C; (iii) The necessity of induction time for the precursors to transform into crystalline nuclei further demonstrates the non-crystalline nature of precursors. The concentration of precursors is observed to reduce with increasing shearing temperature, as evidenced by twisting degree of lamellar crystals after isothermally crystallized at 127 °C.

Graphical abstract

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Intermolecular interactions of poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (P(HB-co-HV)) with PHB-type crystal structure and PHV-type crystal structure studied by low-frequency Raman and terahertz spectroscopy

Publication date: 17 January 2018
Source:Polymer, Volume 135
Author(s): Dian Marlina, Harumi Sato, Hiromichi Hoshina, Yukihiro Ozaki
Composition-, temperature-, and polarization-dependent low-frequency Raman and terahertz (far-infrared; FIR) spectra were measured for poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (P(HB-co-HV)) with PHB-type crystal structure and PHV-type crystal structure to investigate their intermolecular interactions. Band assignments were attempted by comparing the low-frequency Raman and terahertz (FIR) spectra of P(HB-co-HV) with the varying HV content with the corresponding spectra of PHB and by observing spectral variations. The spectra of P(HB-co-HV) (HV = 9, 15, and 21 mol%) are similar to the corresponding spectra of PHB. There are two bands at 97 and 82 cm⁻¹ which are assigned to a spring type vibrational mode of the helical structure and to the mode reflecting the intermolecular interaction (CH3⋯O=C hydrogen bond), respectively. The low-frequency Raman and terahertz spectra of P(HB-co-HV) with HV content of 66 and 88.6 mol% show bands at 91 and 78 cm⁻¹. The 78 cm⁻¹ band is assigned to the intermolecular interaction (CH2⋯O=C hydrogen bond). In contrast to the 97 cm⁻¹ band of P(HB-co-HV) with the low HV content, the 91 cm⁻¹ band of P(HB-co-HV) with the high HV content show a temperature-dependent shift by 4 cm⁻¹. Thus, although it seems that both 97 and 91 cm⁻¹ bands are due to spring-like vibrational modes, the nature of two vibrational modes seems to be significantly different, reflecting the difference in the intermolecular interaction.

Graphical abstract

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Study on phase separation in an ultra-thin poly(methyl methacrylate)/poly(4-vinyl phenol) film by infrared reflection absorption spectroscopy

Publication date: 17 January 2018
Source:Polymer, Volume 135
Author(s): Morihisa Terasaki, Khasanah, Yukihiro Ozaki, Isao Takahashi, Harumi Sato
The phase separation of poly(methyl methacrylate) (PMMA)/poly(4-vinyl phenol) (PVPh) (50/50 wt%) ultra-thin films was investigated by infrared reflection absorption spectroscopy (IR-RAS). Of particular note is that we succeeded in measuring the IR-RAS spectra of ultra-thin films of PMMA/PVPh (50/50 wt%) polymer blend with a film thickness of only 2.14 nm. It was found from the present study that the PMMA/PVPh polymer blends were clearly separated as the film thickness was thinner than the radius of gyration of PMMA. The IR-RAS spectra reveal that the hydrogen bond between the C=O group of PMMA and the OH group of PVPh is broken upon the phase separation in the ultra-thin film. In the spectra, many peaks are observed in the OH stretching region of the ultra-thin PMMA/PVPh films, indicating the existence of several weak hydrogen bonds with slightly different interactions, presumably due to the quasi-stable molecular chain configurations resulting from the strong confinement. This is in sharp contrast to the corresponding bulk sample for which a broad band is usually observed in this region because of the continuous distribution of the hydrogen bonding, which is typical for the blends.

Graphical abstract

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Editorial Board

Publication date: 3 January 2018
Source:Polymer, Volume 134





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Effects of chemical structure on gas transport properties of polyethersulfone polymers

Publication date: 17 January 2018
Source:Polymer, Volume 135
Author(s): Ali Naderi, Wai Fen Yong, Youchang Xiao, Tai-Shung Chung, Martin Weber, Christian Maletzko
Compared to polysulfone (PSF), the effects of chemical structure on gas separation performance of polyethersulfone (PES) are rarely in-depth studied. To explore the potential of various PES polymers as gas separation membranes, PES containing four different backbone structures have been synthesized. They are polyphenylsulfone (PPSU), poly trimethyl benzene ethersulfone (TPESU), polyethersulfone (PESU) and hydrophilic polyethersulfone (HPESU). Both wide-angle X-ray diffraction (XRD) and positron annihilation life-time spectroscopy (PALS) data indicate that PPSU and TPESU have bigger d-space, pore size and fractional free volume (FFV) values than PESU and HPESU. Among the four PES, PPSU stands out with the highest O2 and CO2 permeability of 1.61 and 9.13 Barrer at 35 °C, respectively, because the two additional aryl groups in PPSU contributes to high segmental motions. HPESU has the lowest gas permeability but shows the highest CO2/N2 and CO2/CH4 selectivity of 34.9 and 34.6, respectively, possibly because of the affinity between its polyethylene oxide units and CO2. The addition of trimethyl benzene groups into TPESU not only increases all gas permeability but also increases selectivity of some gas pairs. It has the highest O2/N2 selectivity of 6.0 and the 2nd highest CO2/CH4 selectivity of 33.8. Its O2 and CO2 permeability are 1.33 and 5.74 Barrer at 35 °C, respectively. In contrast, PESU has low gas permeability and average selectivity because of its linear ethersulfone chain structure. In addition, the diffusivity ratio between Henry and Langmuir modes as a function of chain structure has been investigated. The diffusivity ratio is always smaller than 32%. This study may provide useful insights to design better PES polymers for gas separation.

Graphical abstract

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Large-scale reverse Monte Carlo analysis for the morphologies of silica nanoparticles in end-modified rubbers based on ultra-small-angle X-ray scattering data

Publication date: 17 January 2018
Source:Polymer, Volume 135
Author(s): Katsumi Hagita, Tetsuo Tominaga, Takuo Sone
Differences in the morphologies of silica nanoparticles (NPs) in end-modified styrene-butadiene rubber (SBR) and non-modified SBR were analyzed by comparing ultra-small-angle X-ray scattering (USAXS) experiments and transmission electron microscopy (TEM) images. To perform 3D topological data analysis on NPs, a modeling method for the 3D positions of NPs is essential. Reverse Monte Carlo (RMC) analysis is an effective tool for modeling the 3D configuration of NPs from the USAXS data. It was previously reported that the difference in the scattering intensity I(q) between the end-modified and the non-modified SBR can be observed at a q-range of 0.0015–0.06 nm⁻¹. To take such a low q value into account in the RMC analysis, both a large system and a large number of NPs are required. In this study, a large-scale RMC analysis for 33,554,432 NPs, for a wide q-range from 0.0014 to 0.17 nm⁻¹, was performed. The 3D topological data analyses were conducted using the histograms of neighboring particles and the volumes of the Voronoi cells. The results reveal that NPs in the end-modified SBR are better dispersed than those in the non-modified SBR. The histograms of the neighboring particles show that the average size of the aggregated NPs for the modified SBR is smaller than that for the non-modified SBR. From the histograms of the volumes of the Voronoi cells, it is observed that the fraction of the large free volume among the aggregated NPs for the non-modified SBR is larger than that for the modified SBR.

Graphical abstract

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Preparation of ultra-low CTE epoxy composite using the new alkoxysilyl-functionalized bisphenol A epoxy resin

Publication date: 17 January 2018
Source:Polymer, Volume 135
Author(s): Hyunaee Chun, Yun-Ju Kim, Sang-Yong Tak, Sook-Yeon Park, Su-Jin Park, Chang Ho Oh
The high coefficient of thermal expansion (CTE) of the epoxy composite frequently causes the CTE-mismatch problem in semiconductor packaging. However, when the epoxy resins available currently are used for composite, the CTE-mismatch problem is inevitable even at the highly-filled conditions. In this study, the new type of bisphenol A (BPA) epoxy resin, i.e., ethoxysilyl-functionalized BPA epoxy was synthesized for the ultra-low CTE epoxy composite. The new epoxy composite with 85 wt% of silica content showed the ultra-low CTE of 3.2 ppm/°C and 6.0 ppm/°C at the temperature ranges of T < Tg and T > Tg, respectively. For comparison, the non-functionalized BPA epoxy composite was prepared under the similar conditions and it showed the CTE values of 8 ppm/°C and 40 ppm/°C at the temperature ranges of T < Tg and T > Tg, respectively. In order to understand the unique feature of the alkoxysilyl-functionalized epoxy, the reaction mechanism of the new epoxy was investigated using the model compound.

Graphical abstract

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Synthesis, characterization and catalytic properties of salen-containing polymers obtained by atom transfer radical polymerization

Publication date: 17 January 2018
Source:Polymer, Volume 135
Author(s): Nacim Zidelmal, Nadine Aubry-Barroca, Bénédicte Lepoittevin, Mohamed Mellah, Ludovic Costa, François Ozanam, Anne-Chantal Gouget-Laemmel, Emmanuelle Schulz, Philippe Roger
Styrene copolymers containing 5–50 mol % of a comonomer with a salen catalytic-active moiety are synthesized by using ATRP in solution. Control of the synthesis is obtained only when the salen comonomer incorporation is less than 10 mol %. In those conditions, first-order kinetics, linear increase of Mn versus time and monomodal narrow molar mass distributions with molar mass dispersities Ð in the range 1.28–1.33 are satisfactorily achieved. For copolymers with higher incorporated salen comonomer, control of the reaction progressively disappears with dispersities increasing with salen comonomer incorporation up to Р= 1.72. Cobalt complexation of those copolymers allows high yield and selectivity in the catalysis of the dynamic hydrolytic kinetic resolution of epibromohydrin. In spite of the loss of polymerization control, the highest (50%) salen incorporation yields the best catalytic results. Under these conditions, the high concentration of Co catalytic sites might favor the formation of bimetallic complexes responsible for the high activity and enantioselectivity.

Graphical abstract

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Preparation of low molecular weight cyclic polystyrenes with high purity via liquid chromatography at the critical condition

Publication date: 17 January 2018
Source:Polymer, Volume 135
Author(s): Lingfeng Gao, Joongsuk Oh, Yingfeng Tu, Taihyun Chang
Cyclic polymers synthesized by ring-closure method from linear precursors contain some of linear contaminates. In this work, the origin of linear contaminates in cyclic polystyrenes (c-PS) is demonstrated by the coupling of liquid chromatography at the critical condition (LCCC) with matrix-assisted laser desorption/ionization time-of-flight mass spectra. The linear contaminates are revealed to be the "dead" chains during ATRP by chain termination, the unreacted linear polystyrene (l-PS) precursors, and the dimers by the imperfect ring-closure reaction. The c-PS are purified by LCCC fractionation, and the results show the LCCC fractionation at the critical adsorption point (CAP) of c-PS is more efficient than that at the CAP of linears for low molecular weight (<10,000) PS. A two-step LCCC method is presented for the preparation of c-PS with high purity (>99.6%) via the tandem-coupled LCCC fractionation at the CAP of l-PS and at the CAP of c-PS.

Graphical abstract

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Soluble, porous semifluorinated poly(arylene ether) ladder polymers from 2,3,4,5,6-pentafluorobenzonitrile

Publication date: 17 January 2018
Source:Polymer, Volume 135
Author(s): Krishnan Ranganathan, Anbanandam Parthiban
A series of new ladder polymers are synthesized from nucleophilic substitution reactions between tetrafunctional fluorinated monomers derived from 2,3,4,5,6-pentafluorobenzonitrile (PFBN) and various bisphenols such as hydroquinone (HQ), bisphenol-A (BP-A), and 4,4′-(hexafluoroisopropylidene)diphenol (6F-BPA) by a two-step process under mild conditions. The tetrafunctional semi-fluorinated derivatives were obtained by reacting PFBN with nucleophiles such as -S^2-, HQ, BP-A, 6F-BPA in 2:1 mol ratio at room temperature. The tetrafunctional derivatives were subsequently reacted with bisphenols of the same or different type in 1:2 mol ratios respectively to yield soluble porous polymers. The MALDI-TOF MS analysis shows that each repeating unit of polymer chain consists of one unit derived from the tetrafunctional moiety and two bisphenoxy moieties exhibiting ladder structure in the polymer backbone. These polymers exhibit porous nature and the porosity can be fine-tuned by changing the bisphenols at either step.

Graphical abstract

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Self-crosslinkable nitroxide-functionalized poly(2,6-dimethyl-1,4-phenylene oxide) through atom transfer radical coupling reaction

Publication date: 17 January 2018
Source:Polymer, Volume 135
Author(s): Chia-Yu Lin, Chien-Ho Huang, Chien-Chieh Hu, Ying-Ling Liu
Nitroxide-functionalized polymers are attractive macroinitiators for nitroxide mediated polymerization (NMP) and further modification of polymers. In this work, a facile reaction method to chemically bond nitroxide groups to polymer chains has been demonstrated with incorporation of 2,2,6,6-tetramethylpiperydinyl-1-oxyl (TEMPO) groups into poly(2,6-dimethyl-1,4-phenylene oxide) (PPO) through the atom transfer radical coupling reaction. The TEMPO-functionalized PPO (PPO-TEMPO) has been used as a macroinitiator for NMP of styrene to result in the corresponding PPO-g-PS graft copolymers. Moreover, PPO-TEMPO could be used to carry out a thermally-induced self-crosslinking reaction through radical coupling. The crosslinked PPO displays enhanced mechanical properties, reduced oxygen permeability coefficient (from 22.5 barrer to 3.5 barrer), low dielectric constant (2.40 at 10 GHz) and low dissipation factor (0.008 at 10 GHz), so as to have high potential for application in dielectric layers of microelectronics.

Graphical abstract

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Novel biobased copolyesters based on 1,2-propanediol or 2,3-butanediol with the same ethylene skeletal structure as PETG

Publication date: 17 January 2018
Source:Polymer, Volume 135
Author(s): Ji-Hyun Kim, Jong-Ryang Kim, Cheol-Hee Ahn
New potentially biobased copolyesters having the same ethylene skeletal structure as poly(ethylene glycol-co-1,4-cyclohexanedimethanol terephthalate) (PETG) were synthesized based on 1,2-propanediol (1,2-PD) or 2,3-butanediol (2,3-BD) with 1,4-cyclohexane dimethanol (CHDM). The compositions of each copolyester were confirmed using ¹H-NMR spectroscopy, and the detailed structure was analyzed using 2D NMR spectroscopy. In order to observe the effect of the lateral methyl groups on the microstructure and randomness in the sequences of the copolymers, ¹³C-NMR spectroscopy analysis was performed. The thermal properties, mechanical properties, and crystallinity of the copolyesters were analyzed using differential scanning calorimetry, thermogravimetric analysis, universal testing machine, and wide-angle X-ray diffraction. Depending on the number of the lateral methyl groups and the contents of the ethylene diol units, the copolyesters displayed different densities, glass transition temperatures (Tg), degrees of randomness and mechanical properties; however, a notable difference was not observed in thermal stability or crystallinity.

Graphical abstract

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Editorial Advisory Board

Publication date: February 2018
Source:Ultrasound in Medicine & Biology, Volume 44, Issue 2





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Contents

Publication date: February 2018
Source:Ultrasound in Medicine & Biology, Volume 44, Issue 2





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Calendar

Publication date: February 2018
Source:Ultrasound in Medicine & Biology, Volume 44, Issue 2





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Bowel Sonoelastography in Patients with Crohn's Disease: A Systematic Review

Publication date: February 2018
Source:Ultrasound in Medicine & Biology, Volume 44, Issue 2
Author(s): Lorenzo Carlo Pescatori, Giovanni Mauri, Edoardo Savarino, Luca Pastorelli, Maurizio Vecchi, Luca Maria Sconfienza
Sonoelastography is an ultrasound-based method for evaluating the biological properties of a target tissue. It is commonly used in the diagnosis of liver and thyroid disease, but recently its use for monitoring the characteristics of bowel wall in patients affected by Crohn's disease (CD) has been proposed. Our aim was a systematic review of the use of sonoelastography in patients with CD. An initial database search retrieved 32 possible articles. On initial screening, 7 articles, concerning a total of 129 patients and 154 lesions of the small and large bowel, were finally included in the review. The age range varied between 6 and 53 y, and disease duration ranged between 1 and 623 mo. We collected data on the examinations performed (type and time), bowel area considered and parameters evaluated. All authors found that elastography correlates well with the degree of fibrosis, as wall strain significantly decreases in segments affected by fibrotic stenosis. Even though the endpoints proposed in the various articles are relatively inhomogeneous and scarcely comparable, we found that sonoelastography is a promising tool in the evaluation of patients with CD as it can differentiate inflammatory and fibrotic strictures in small case series.



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Evaluating the Benefit of Elevated Acoustic Output in Harmonic Motion Estimation in Ultrasonic Shear Wave Elasticity Imaging

Publication date: February 2018
Source:Ultrasound in Medicine & Biology, Volume 44, Issue 2
Author(s): Yufeng Deng, Mark L. Palmeri, Ned C. Rouze, Clare M. Haystead, Kathryn R. Nightingale
Harmonic imaging techniques have been applied in ultrasonic elasticity imaging to obtain higher-quality tissue motion tracking data. However, harmonic tracking can be signal-to-noise ratio and penetration depth limited during clinical imaging, resulting in decreased yield of successful shear wave speed measurements. A logical approach is to increase the source pressure, but the in situ pressures used in diagnostic ultrasound have been subject to a de facto upper limit based on the Food and Drug Administration guideline for the mechanical index (MI <1.9). A recent American Institute of Ultrasound in Medicine report concluded that an in situ MI up to 4.0 could be warranted without concern for increased risk of cavitation in non-fetal tissues without gas bodies if there were a concurrent clinical benefit. This work evaluates the impact of using an elevated MI in harmonic motion tracking for hepatic shear wave elasticity imaging. The studies indicate that high-MI harmonic tracking increased shear wave speed estimation yield by 27% at a focal depth of 5 cm, with larger yield increase in more difficult-to-image patients. High-MI tracking improved harmonic tracking data quality by increasing the signal-to-noise ratio and decreasing jitter in the tissue motion data. We conclude that there is clinical benefit to use of elevated acoustic output in shear wave tracking, particularly in difficult-to-image patients.



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Comprehensively Assessing the Acute Femoral Cartilage Response and Recovery after Walking and Drop-Landing: An Ultrasonographic Study

Publication date: February 2018
Source:Ultrasound in Medicine & Biology, Volume 44, Issue 2
Author(s): Matthew S. Harkey, J. Troy Blackburn, Anthony C. Hackney, Michael D. Lewek, Randy J. Schmitz, Daniel Nissman, Brian Pietrosimone
We compared the acute response and recovery of ultrasonography (US) cartilage outcomes (i.e., thickness, cross-sectional area, and echo intensity) between walking, drop-landing and control conditions in 43 young adults with no history of lower extremity injury. A femoral cartilage US assessment was performed before and after each condition to determine the acute cartilage response and recovery at 15, 30 and 45 min. Percentage change scores from pre- to all post-time points were used for analysis. Acute cartilage response and recovery were analyzed with a 3 × 4 (condition × time) repeated-measures analysis of variance. Greater deformation of the medial and lateral femoral cartilage was observed immediately after both the walking and drop-landing conditions compared with the control condition. Cartilage deformation after the drop-landing condition required longer time to recover compared with the walking condition. The femoral cartilage deformation was not accompanied by concurrent alterations in cartilage echo intensity.



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Masthead

Publication date: February 2018
Source:Ultrasound in Medicine & Biology, Volume 44, Issue 2





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An Ultrasound Surface Wave Technique for Assessing Skin and Lung Diseases

Publication date: February 2018
Source:Ultrasound in Medicine & Biology, Volume 44, Issue 2
Author(s): Xiaoming Zhang, Boran Zhou, Sanjay Kalra, Brian Bartholmai, James Greenleaf, Thomas Osborn
Systemic sclerosis (SSc) is a multi-organ connective tissue disease characterized by immune dysregulation and organ fibrosis. Severe organ involvement, especially of the skin and lung, is the cause of morbidity and mortality in SSc. Interstitial lung disease (ILD) includes multiple lung disorders in which the lung tissue is fibrotic and stiffened. The purpose of this study was to translate ultrasound surface wave elastography (USWE) for assessing patients with SSc and/or ILD via measuring surface wave speeds of both skin and superficial lung tissue. Forty-one patients with both SSc and ILD and 30 healthy patients were enrolled in this study. An external harmonic vibration was used to generate the wave propagation on the skin or lung. Three excitation frequencies of 100, 150 and 200 Hz were used. An ultrasound probe was used to measure the wave propagation in the tissue non-invasively. Surface wave speeds were measured on the forearm and upper arm of both left and right arm, as well as the upper and lower lungs, through six intercostal spaces of patients and healthy patients. Viscoelasticity of the skin was calculated by the wave speed dispersion with frequency using the Voigt model. The magnitudes of surface wave speed and viscoelasticity of patients' skin were significantly higher than those of healthy patients (p < 0.0001) for each location and each frequency. The surface wave speeds of patients' lung were significantly higher than those of healthy patients (p < 0.0001) for each location and each frequency. USWE is a non-invasive and non-ionizing technique for measuring both skin and lung surface wave speed and may be useful for quantitative assessment of SSc and/or ILD.



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Determination of Acoustic Cavitation Probabilities and Thresholds Using a Single Focusing Transducer to Induce and Detect Acoustic Cavitation Events: I. Method and Terminology

Publication date: February 2018
Source:Ultrasound in Medicine & Biology, Volume 44, Issue 2
Author(s): Julian Haller, Volker Wilkens, Adam Shaw
A method to determine acoustic cavitation probabilities in tissue-mimicking materials (TMMs) is described that uses a high-intensity focused ultrasound (HIFU) transducer for both inducing and detecting the acoustic cavitation events. The method was evaluated by studying acoustic cavitation probabilities in agar-based TMMs with and without scatterers and for different sonication modes like continuous wave, single pulses (microseconds to milliseconds) and repeated burst signals. Acoustic cavitation thresholds (defined here as the peak rarefactional in situ pressure at which the acoustic cavitation probability reaches 50%) at a frequency of 1.06 MHz were observed between 1.1 MPa (for 1 s of continuous wave sonication) and 4.6 MPa (for 1 s of a repeated burst signal with 25-cycle burst length and 10-ms burst period) in a 3% (by weight) agar phantom without scatterers. The method and its evaluation are described, and general terminology useful for standardizing the description of insonation conditions and comparing results is provided. In the accompanying second part, the presented method is used to systematically study the acoustic cavitation thresholds in the same material for a range of sonication modes.



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Response to the Letter to the Editor-in-Chief on Manuscript Entitled: Transbulbar B-Mode Sonography in Multiple Sclerosis: Clinical and Biological Relevance

Publication date: February 2018
Source:Ultrasound in Medicine & Biology, Volume 44, Issue 2
Author(s): Roberto De Masi, Stefania Orlando




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Determination of Acoustic Cavitation Probabilities and Thresholds Using a Single Focusing Transducer to Induce and Detect Acoustic Cavitation Events: II. Systematic Investigation in an Agar Material

Publication date: February 2018
Source:Ultrasound in Medicine & Biology, Volume 44, Issue 2
Author(s): Julian Haller, Volker Wilkens
In the accompanying article (Part I), a method is described to determine acoustic cavitation probabilities in tissue-mimicking materials (TMMs) using a high-intensity focused ultrasound (HIFU) transducer for both inducing and detecting the acoustic cavitation events, and its suitability for different sonication modes like continuous wave, single pulses (with pulse lengths from microseconds to milliseconds) and repeated burst signals is discussed. In Part II, the use of the method for a systematic study of the dependence of the acoustic cavitation thresholds in 3% (by weight) agar phantoms on the temporal sonication parameters is discussed. The values obtained at a frequency of 1.06 MHz, ranging from (0.58 ± 0.12) MPa for a 3-s continuous wave mode sonication to (5.2 ± 1.0) MPa for single shots with a length of 10 wave cycles, are discussed and interpreted on the basis of literature values and their self-consistency.



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Lipid Microbubbles as Ultrasound-Stimulated Oxygen Carriers for Controllable Oxygen Release for Tumor Reoxygenation

Publication date: February 2018
Source:Ultrasound in Medicine & Biology, Volume 44, Issue 2
Author(s): Chunjiang Yang, Huan Xiao, Yang Sun, Lirong Zhu, Yang Gao, Sunny Kwok, Zhigang Wang, Yi Tang
Microbubbles are proposed as a potentially novel method for oxygen delivery in vivo in initial studies. The lack of commercial microbubbles for oxygen delivery in preclinical research prompted us to fabricate an oxygen-loaded lipid microbubble. We aimed to extend the innovative strategy to modulate the tumor hypoxic microenvironment, using microbubbles intravenously as an oxygen carrier for the controllable tumor-specific delivery of oxygen by ultrasound (US). In our experiment, an oxygen-loaded lipid-coated microbubble (OLM) with mixed gas (O2/C3 F8, 5:1 v/v) was fabricated and exhibited a higher rate of oxygen release to a desaturated solution through burst by US than that in the absence of US. Although in in vivo studies, OLMs could be imaged and triggered by US to elevate the pO2 level in the breast VX2 tumor dramatically within a matter of minutes. The added presence of US-activated OLMs elicited a nearly six-fold increase in pO2 levels within 1 min compared with that of the pre-injection. Owing to the high oxygen payload, great acoustic stability and acoustic properties, OLMs may be proposed as an ideal radio-sensitizer. We conclude that oxygen release mediated by ultrasound-targeted microbubble destruction is feasible and shows potential in image-guided, site-specific cancer radiotherapy.



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Repeatability of Contrast-Enhanced Ultrasonography of the Kidneys in Healthy Cats

Publication date: February 2018
Source:Ultrasound in Medicine & Biology, Volume 44, Issue 2
Author(s): Emmelie Stock, Luc Duchateau, Jimmy H. Saunders, Veerle Volckaert, Ingeborgh Polis, Katrien Vanderperren
Contrast-enhanced ultrasound can be used to image and quantify tissue perfusion. It holds great potential for the use in the diagnosis of various diffuse renal diseases in both human and veterinary medicine. Nevertheless, the technique is known to have an inherent relatively high variability, related to various factors associated with the patient, the contrast agent and machine settings. Therefore, the aim of this study was to assess week-to-week intra- and inter-cat variation of several perfusion parameters obtained with CEUS of both kidneys of 12 healthy cats. Repeatability was determined by calculating the coefficient of variation (CV). The contrast-enhanced ultrasound parameters with the lowest variation for the renal cortex were time-to-peak (CV 6.0%), rise time (CV 13%), fall time (CV 19%) and mean transit time (24%). Intensity-related parameters and parameters related to the slope of the time-intensity curve had a CV of >35%. Lower repeatability was present for perfusion parameters derived from the renal medulla compared with the renal cortex. Normalization to the inter-lobar artery does not cause a reduction in variation. In conclusion, time-related parameters for the cortex show a reasonable repeatability; whereas poor repeatability is present for intensity-related parameters and parameters related to in- and outflow of contrast agent. Poor repeatability is also present for all perfusion parameters for the renal medulla, except for time to peak, which has a good repeatability.



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Effect of Temperature on the Size Distribution, Shell Properties, and Stability of Definity®

Publication date: February 2018
Source:Ultrasound in Medicine & Biology, Volume 44, Issue 2
Author(s): Himanshu Shekhar, Nathaniel J. Smith, Jason L. Raymond, Christy K. Holland
Physical characterization of an ultrasound contrast agent (UCA) aids in its safe and effective use in diagnostic and therapeutic applications. The goal of this study was to investigate the impact of temperature on the size distribution, shell properties, and stability of Definity^®, a U.S. Food and Drug Administration-approved UCA used for left ventricular opacification. A Coulter counter was modified to enable particle size measurements at physiologic temperatures. The broadband acoustic attenuation spectrum and size distribution of Definity^® were measured at room temperature (25 °C) and physiologic temperature (37 °C) and were used to estimate the viscoelastic shell properties of the agent at both temperatures. Attenuation and size distribution was measured over time to assess the effect of temperature on the temporal stability of Definity^®. The attenuation coefficient of Definity^® at 37 °C was as much as 5 dB higher than the attenuation coefficient measured at 25 °C. However, the size distributions of Definity^® at 25 °C and 37 °C were similar. The estimated shell stiffness and viscosity decreased from 1.76 ± 0.18 N/m and 0.21 × 10^–6 ± 0.07 × 10^–6 kg/s at 25 °C to 1.01 ± 0.07 N/m and 0.04 × 10^–6 ± 0.04 × 10^–6 kg/s at 37 °C, respectively. Size-dependent differences in dissolution rates were observed within the UCA population at both 25 °C and 37 °C. Additionally, cooling the diluted UCA suspension from 37 °C to 25 °C accelerated the dissolution rate. These results indicate that although temperature affects the shell properties of Definity^® and can influence the stability of Definity^®, the size distribution of this agent is not affected by a temperature increase from 25 °C to 37 °C.



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Quantitative Evaluation of Denervated Muscle Atrophy with Shear Wave Ultrasound Elastography and a Comparison with the Histopathologic Parameters in an Animal Model

Publication date: February 2018
Source:Ultrasound in Medicine & Biology, Volume 44, Issue 2
Author(s): Jing Wen, Yuexiang Wang, Wenli Jiang, Yukun Luo, Jiang Peng, Mingxue Chen, Xiaoguang Jing
This study explored the efficacy of shear wave ultrasound elastography (SWUE) for quantitative evaluation of denervated muscle atrophy in a rabbit model. The elastic modulus of the triceps surae muscle was measured with SWUE and compared with histopathologic parameters at baseline and at various post-denervation times (2, 4 and 8 wk) with 10 animals in each group. Our results revealed that the elastic modulus of denervated muscle was significantly lower at 2 wk but higher at 8 wk compared with that at the baseline (p < 0.05), and no significant difference was found between the elastic modulus at 4 wk and that at the baseline (p > 0.05). The wet-weight ratio and the muscle fiber cross-sectional area of the denervated muscle decreased gradually during the 8 wk post-denervation together with a gradual increase of the collagen fiber area (p < 0.05). In conclusion, SWUE was useful for quantitative evaluation of muscle denervation. The decreased elastic modulus might be an early sign of denervated muscle atrophy.



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Development and Validation of a Phase-Filtered Moving Ensemble Correlation for Echocardiographic Particle Image Velocimetry

Publication date: February 2018
Source:Ultrasound in Medicine & Biology, Volume 44, Issue 2
Author(s): Brett A. Meyers, Craig J. Goergen, Pavlos P. Vlachos
A new processing method for echocardiographic particle image velocimetry (EchoPIV) using moving ensemble (ME) correlation with dynamic phase correlation filtering was developed to improve velocity measurement accuracy for routine clinical evaluation of cardiac function. The proposed method was tested using computationally generated echocardiogram images. Error analysis indicated that ME EchoPIV yields a twofold improvement in bias and random error over the current standard correlation method (βPairwise = −0.15 vs. βME = −0.06; σPairwise = 1.00 vs. σME = 0.49). Subsequently a cohort of eight patients with impaired diastolic filling underwent similar evaluation. Comparison of patient EchoPIV velocity time series with corresponding color M-mode velocity time series revealed better agreement for ME EchoPIV compared with standard PIV processing (RME = 0.90 vs. RPairwise = 0.70). Further time series analysis was performed to measure filling propagation velocity and 1-D intraventricular pressure gradients. Comparison against CMM values indicated that both measurements are completely decorrelated for pairwise processing (R²Vp = 0.15, R²IVPD = 0.07), whereas ME processing correlates decently (R²Vp = 0.69, R²IVPD = 0.69). This new approach enables more robust processing of routine clinical scans and can increase the utility of EchoPIV for the assessment of left ventricular function.



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A Novel Method of Synovitis Stratification in Ultrasound Using Machine Learning Algorithms: Results From Clinical Validation of the MEDUSA Project

Publication date: February 2018
Source:Ultrasound in Medicine & Biology, Volume 44, Issue 2
Author(s): Pawel Mielnik, Marcin Fojcik, Jakub Segen, Marek Kulbacki
Ultrasound is widely used in the diagnosis and follow-up of chronic arthritis. We present an evaluation of a novel automatic ultrasound diagnostic tool based on image recognition technology. Methods used in developing the algorithm are described elsewhere. For the purpose of evaluation, we collected 140 ultrasound images of metacarpophalangeal and proximal interphalangeal joints from patients with chronic arthritis. They were classified, according to hypertrophy size, into four stages (0–3) by three independent human observers and the algorithm. An agreement ratio was calculated between all observers and the standard derived from results of human staging using κ statistics. Results was significant in all pairs, with the highest p value of 3.9 × 10^–6. κ coefficients were lower in algorithm/human pairs than between human assessors. The algorithm is effective in staging synovitis hypertrophy. It is, however, not mature enough to use in a daily practice because of limited accuracy and lack of color Doppler recognition. These limitations will be addressed in the future.



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Ultrasound Determination of the Femoral Head-Neck Alpha Angle

Publication date: February 2018
Source:Ultrasound in Medicine & Biology, Volume 44, Issue 2
Author(s): D.J. Robinson, S. Lee, P. Marks, M.E. Schneider
The femoral head-neck alpha angle is used to quantify the degree of femoral head asphericity in patients suspected of cam-type femoroacetabular impingement. The measurement was first performed using magnetic resonance imaging and, more recently, three-dimensional computed tomography (CT). We set out to determine whether the alpha angle could be reliably measured using ultrasound. Patients were recruited from a cohort presenting for CT of the hip. Alpha angles were calculated following the departmental protocol by institutionally accredited radiographers. After the CT, patients were imaged with ultrasound and the alpha angle calculated from the ultrasound image by a sonographer blinded to the CT result. Statistical comparison of the two methods was performed with the Bland-Altman test using SPSS (version 21.0, Chicago, USA), and a p < 0.05 afforded significance. Twenty-eight patients were recruited. Eleven patients were bilateral examinations, providing 39 hips for analysis. There were 15 females and 13 males, with 21 right and 18 left hips examined. Average patient age (±standard deviation) was 40 y (±13.9 y). Mean (±standard deviation) measurements for CT and ultrasound were 62.5° (±14.2°) and 64.5° (±12.6°), respectively. The mean absolute difference between the two methods was 10.5° (95% confidence interval 6.9°–14.0°). Sensitivity of each individual ultrasound measurement was 91.3%. The specificity of ultrasound was 43.75%. The positive predictive value was 0.7, and the negative predictive value was 0.78. Overall accuracy of the ultrasound-derived alpha angle was calculated at 0.718. Ultrasound demonstrates good sensitivity and good negative predictive value in calculation of the femoral head-neck alpha angle compared with CT; however, specificity is low. Ultrasound measurement of the alpha angle can provide objective evidence of cam-type femoroacetabular impingement in symptomatic patients and can direct patients to more established imaging techniques where appropriate.



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3D spatially-adaptive canonical correlation analysis: Local and global methods

Publication date: 1 April 2018
Source:NeuroImage, Volume 169
Author(s): Zhengshi Yang, Xiaowei Zhuang, Karthik Sreenivasan, Virendra Mishra, Tim Curran, Richard Byrd, Rajesh Nandy, Dietmar Cordes
Local spatially-adaptive canonical correlation analysis (local CCA) with spatial constraints has been introduced to fMRI multivariate analysis for improved modeling of activation patterns. However, current algorithms require complicated spatial constraints that have only been applied to 2D local neighborhoods because the computational time would be exponentially increased if the same method is applied to 3D spatial neighborhoods.In this study, an efficient and accurate line search sequential quadratic programming (SQP) algorithm has been developed to efficiently solve the 3D local CCA problem with spatial constraints. In addition, a spatially-adaptive kernel CCA (KCCA) method is proposed to increase accuracy of fMRI activation maps. With oriented 3D spatial filters anisotropic shapes can be estimated during the KCCA analysis of fMRI time courses. These filters are orientation-adaptive leading to rotational invariance to better match arbitrary oriented fMRI activation patterns, resulting in improved sensitivity of activation detection while significantly reducing spatial blurring artifacts. The kernel method in its basic form does not require any spatial constraints and analyzes the whole-brain fMRI time series to construct an activation map. Finally, we have developed a penalized kernel CCA model that involves spatial low-pass filter constraints to increase the specificity of the method.The kernel CCA methods are compared with the standard univariate method and with two different local CCA methods that were solved by the SQP algorithm. Results show that SQP is the most efficient algorithm to solve the local constrained CCA problem, and the proposed kernel CCA methods outperformed univariate and local CCA methods in detecting activations for both simulated and real fMRI episodic memory data.



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The role of the cerebellum in explicit and incidental processing of facial emotional expressions: A study with transcranial magnetic stimulation

Publication date: 1 April 2018
Source:NeuroImage, Volume 169
Author(s): Chiara Ferrari, Viola Oldrati, Marcello Gallucci, Tomaso Vecchi, Zaira Cattaneo
Growing evidence suggests that the cerebellum plays a critical role in non-motor functions, contributing to cognitive and affective processing. In particular, the cerebellum might represent an important node of the "limbic" network, underlying not only emotion regulation but also emotion perception and recognition. Here, we used transcranial magnetic stimulation (TMS) to shed further light on the role of the cerebellum in emotional perception by specifically testing cerebellar contribution to explicit and incidental emotional processing. In particular, in three different experiments, we found that TMS over the (left) cerebellum impaired participants' ability to categorize facial emotional expressions (explicit task) and to classify the gender of emotional faces (incidental emotional processing task), but not the gender of neutral faces. Overall, our results indicate that the cerebellum is involved in perceiving the emotional content of facial stimuli, even when this is task irrelevant.



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Desert actinobacteria as a source of bioactive compounds production with a special emphases on Pyridine-2,5-diacetamide a new pyridine alkaloid produced by Streptomyces sp. DA3-7

Publication date: March 2018
Source:Microbiological Research, Volume 207
Author(s): Krishnasamy Nithya, Chinnasamy Muthukumar, Bhaskar Biswas, Naiyf S. Alharbi, Shine Kadaikunnan, Jamal M. Khaled, Dharumadurai Dhanasekaran
In the present study, 134 morphologically distinct actinobacteria isolates were obtained from soil samples from 10 different localities in the Saudi Arabian desert. The preliminary screening revealed that 16 of these isolates possessed antimicrobial activity. One isolate, which was identified as Streptomyces sp. DA3-7, possessed broad-spectrum antimicrobial activity against both gram-positive and gram-negative bacteria, as well as against fungi, and modified nutrient glucose medium was suitable for Streptomyces sp. DA3-7 to produce extracellular metabolites. The ethyl acetate extract of Streptomyces sp. DA3-7 exhibited antimicrobial activity against Enterococcus faecalis and Salmonella typhimurium, with minimum inhibitory concentrations of 78 and 156μg/mL, respectively, as well as strong cytotoxicity (24h IC50 85μg/mL) against MCF-7 human breast adenocarcinoma cells. The active compound was separated, purified, and identified as Pyridine-2,5-diacetamide (C9H11N3O2+H+, 194.21), which possessed a lowest minimum inhibitory concentration (31.25μg/mL) against both Escherichia coli and Cryptococcus neoformans. The antimicrobial activities of this novel compound are reported here for the first time.



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Multifarious plant growth promotion by an entomopathogenic fungus Lecanicillium psalliotae

Publication date: March 2018
Source:Microbiological Research, Volume 207
Author(s): C.M. Senthil Kumar, T.K. Jacob, S. Devasahayam, Stephy Thomas, C. Geethu
An entomopathogenic fungus, Lecanicillium psalliotae strain IISR-EPF-02 previously found infectious to cardamom thips, Sciothrips cardamomi promoted plant growth in cardamom, Elettaria cardamomum. The isolate exhibited direct plant growth promoting traits by production of indole-3-acetic acid and ammonia and by solubilizing inorganic phosphate and zinc. It also showed indirect plant growth promoting traits by producing siderophores and cell wall-degrading enzymes like, α-amylases, cellulases and proteases. In pot culture experiments, application of the fungus at the root zone of cardamom seedlings significantly increased shoot and root length, shoot and root biomass, number of secondary roots and leaves and leaf chlorophyll content compared to untreated plants. This is the first report on the plant growth promoting traits of this fungus. The entomopathogenic and multifarious growth promoting traits of L. psalliotae strain IISR-EPF-02 suggest that it has great potential for exploitation in sustainable agriculture.

Graphical abstract

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For the greater good: Programmed cell death in bacterial communities

Publication date: March 2018
Source:Microbiological Research, Volume 207
Author(s): Stijn H. Peeters, Marien I. de Jonge
For a long a time programmed cell death was thought to be a unique characteristic of higher eukaryotes, but evidence has accumulated showing that programmed cell death is a universal phenomenon in all life forms. Many different types of bacterial programmed cell death systems have been identified, rivalling the eukaryotic systems in diversity. Bacteria are singular, seemingly independently living organisms, however they are part of complex communities. Being part of a community seems indispensable for survival in different environments. This review is focussed on the mechanism of and reasons for bacterial programmed cell death in the context of bacterial communities.



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Informed Guessing in Change Detection.

Author: Rhodes, Stephen; Cowan, Nelson; Hardman, Kyle O.; Logie, Robert H.

DOI: 10.1037/xlm0000495

Publication Date: POST AUTHOR CORRECTIONS, 21 December 2017

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Osteon Myospalacem Baileyi attenuates osteoclast differentiation through RANKL induced NFAT pathways

Publication date: 1 March 2018
Source:Journal of Ethnopharmacology, Volume 213
Author(s): Yulei Cui, Xiaoying Zhao, Lijuan Mei, Jinjin Pei, Shuo Wang, Yun Shao, Yanduo Tao, Xiaoling Zhang, Lei Jiang
Ethnopharmacological relevanceOsteon Myospalacem Baileyi, known as Sai long gu (Tibetan language, means "blind rat bone"), is the whole skeleton of Tibet plateau rodentia animal Myospalacem Baileyi. Osteon Myospalacem Baileyi had been widely used in the Tibet region as an anti-osteoporosis drug and since 1991 Osteon Myospalacem Baileyi has been listed in the Pharmacopoeia of People's Republic of China as the first-class animal new medical material. However, the mechanism of its anti-osteoporosis activities is still unclear. It is very desirable to solve this problem for further study.Materials and methodsin this study, preparative chromatography was employed to produce the active fraction ET4 from Osteon Myospalacem Baileyi crude. Flow cytometry and MTT assay were used to evaluate the toxicities of ET4. BMM cells were separated from mouse bone marrow to test the inhibition effects of ET4 on osteoclastogenesis. Western blot was used to find out the pathways, through which ET4 could act on osteoclastogenesis. Q-PCR was used to test the osteoclastogenesis marker genes. At last, immunofluorescence confocal microscopy was used to test the osteoclastogenesis master protein NFATc1 nuclei translocation.ResultsIn this study we report that ET4, at the dose of 60μg/mL, significantly inhibited the formation of osteoclasts. Notably, ET4 did not affect the BMM viability at that dose. In addition, Osteon Myospalacem Baileyi could inhibit the expression of osteoclast marker genes, including cathepsin K (CTSK), nuclear factor of activated T cells cytoplasmic 1 (NFATc1), tartrate resistant acid phosphatase (TRAP, Acp5) dendrite cell-specific transmembrane protein (DC-STAMP), calcitonin receptor (CTR), osteoclast associated and immunoglobulin-like receptor (OSCAR). Mechanistically, ET4 dose- and time-dependently blocked the RANKL-induced activation of ERK and c-Fos as well as the induction of NFATc1 which is essential for OC formation.ConclusionsThese data suggest that ET4 might be a useful alternative therapy in preventing or treating osteolytic diseases.

Graphical abstract

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Standardized fraction of Xylocarpus moluccensis fruits improve vascular relaxation and plaque stability in dyslipidemic models of atherosclerosis

Publication date: 1 March 2018
Source:Journal of Ethnopharmacology, Volume 213
Author(s): Jitendra S. Kanshana, Sanjay C. Rebello, Priya Pathak, Babu Nageswararao Kanuri, Hobby Aggarwal, Vasundhara Srivastava, Vivek Khanna, Vishal Singh, Kumaravelu Jagavelu, Manoj K. Barthwal, Madhu Dikshit
Ethnopharmacological relevanceXylocarpus moluccensis (Lamk.) M. Roem of family Meliaceae has triterpenoids rich fruits. Triterpenoids have been known to possess cardioprotection and anti-atherosclerotic activities (Han and Bakovic, 2015; Wu et al., 2009). Standardized fraction of these fruits exhibited anti-dyslipidemic (Srivastava et al., 2015), anti-inflammatory (Ravangpai et al., 2011) and CNS depressant activity (Sarker et al., 2007). However, there is no report in the literature on its cardiovascular effects.Aim of the studyThe present study was undertaken to assess vasoprotective, anti-atherosclerotic and further examine the anti-dyslipidemic effect of the standardized fraction of Xylocarpus moluccensis (F018) fruits in the mechanical injury and high fat diet (HFD) induced dyslipidemic/ atherosclerosis models.Materials and methodsGuinea pigs were fed 0.08% cholesterol + 15% fat diet for 3 weeks, while ApoE KO mice were fed high fat diet for 18 weeks to induce dyslipidemia and atherosclerosis. A combination of balloon injury and high fat diet (1% cholesterol, 6% peanut oil) for 5 weeks was used to accelerate atherosclerosis in NZW rabbits. F018 was administered once daily by oral route in guinea pigs (10, 25 or 50mg/kg/day for 3 weeks), ApoE KO mice (50mg/kg/day for 6 weeks) and in NZW rabbit (25mg/kg/day for 5 weeks) to monitor its effect on dyslipidemia, vasoreactivity and plaque composition by using standard methodologies.ResultsF018 treatment in guinea pigs (25 and 50mg/kg/day), ApoE mice (50mg/kg/day) and rabbits (25mg/kg/day) significantly reduced plasma lipids and improved ACh induced vasorelaxation. Anti-dyslipidemic effect of F018 seems to be due to the modulation of enterohepatic genes involved in the cholesterol absorption and excretion. Moreover, significant improvement in the acetylcholine (ACh) induced vasorelaxation was accompanied with reduced inflammatory burden and enhanced activation of eNOS in ApoE mice aortic tissue. Similarly inflammatory cytokines, immunolabeling of macrophage marker (CD68) and MMP-9 were reduced along with augmentation in vascular smooth muscle cells and collagen type I and III in the mechanically injured iliac artery segment in the rabbits.ConclusionsAltogether, F018 preserved vasoreactivity, reduced atherosclerotic plaque progression and enhanced plaque stability by reducing lipids, inflammatory cytokines, improving endothelial function and collagen content.



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A review of the traditional and modern uses of Salvadora persica L. (Miswak): Toothbrush tree of Prophet Muhammad

Publication date: 1 March 2018
Source:Journal of Ethnopharmacology, Volume 213
Author(s): Muhammad Zakariyyah Aumeeruddy, Gokhan Zengin, Mohamad Fawzi Mahomoodally
Ethnopharmacological relevanceSalvadora persica L., also known as Arak (in Arabic) and Peelu (in Urdu), is the most common traditional source of tooth or chewing stick (miswak) highly recommended by Prophet Muhammad. To date, extensive studies have probed primarily into the validation of its traditional uses in oral care. Nonetheless, there is still a dearth of updated compilation and critical analysis of other potential ethnopharmacological properties of S. persica. This review therefore aims to provide an up-to-date detailed structured description of the traditional uses of S. persica and a critical analysis of its modern uses, highlighting its phytochemistry, pharmacological properties, and bioapplications.Materials and methodsVarious databases (Science Direct, PubMed, Wiley Online Library, and Google Scholar), books, and relevant primary sources were probed, surveyed, analysed, and included in this review. The literature cited in this review dated from 1979 to 2017.ResultsS. persica was found to possess a plethora of bioactive compounds and broad pharmacological properties, including antimicrobial, antioxidant, enzyme inhibitory activity, antiulcer, anticonvulsant, sedative, analgesic, anti-inflammatory, hypoglycemic, hypolipidemic, antiosteoporosis, and antitumor activities. Studies also revealed the potential use of S. persica as a natural food preservative and a novel functional food ingredient. In addition, improvement in growth and reproductive performances have been observed by the introduction of S. persica in animal feed. Lastly, S. persica has also been used in the green synthesis of nanoparticles showing potential biotechnological applications.ConclusionS. persica showed a wide scope of application and its uses have been extended far beyond the initial traditional uses of its roots, stems, and twigs in oral care. We found a number of other ethnopharmacological uses and potential bioapplications of different parts of S. persica that warrants further investigations. Though widely studied using several in vitro and in vivo models, and tested clinically for oral hygiene mainly, several gaps and research priorities have been identified which needs to be addressed in future.

Graphical abstract

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Extraction, fractionation and re-fractionation of Artemisia nilagirica for anticancer activity and HPLC-ESI-QTOF-MS/MS determination

Publication date: 1 March 2018
Source:Journal of Ethnopharmacology, Volume 213
Author(s): Neha Sahu, Sanjeev Meena, Vijaya Shukla, Priyank Chaturvedi, Brijesh Kumar, Dipak Datta, K.R. Arya
Ethnopharmacological relevanceMedicinal plants used in traditional medicines are affordable, easily accessible, safer, less toxic and considered as a rich or efficient source of bioactive molecules for modern therapeutics. Artemisia nilagirica (AR) has a long history of use in Indian traditional medicine to combat a wide variety of diseases including cancer.Aim of the studyConsidering the vast potential of traditional healing plants to deliver safer, less toxic and efficient chemotherapeutics, we have examined anticancer activity of ethanolic extract, bioactive fractions and sub-fractions of AR against different human cancer cell lines along with their phytochemical analysis to understand the insights of novel anticancer activities for further preclinical studies.Materials and methodsFresh plant material of AR was procured from the wild, dried and ground. The grinded materials was extracted in ethanol (AR-01) and fractionated into butanol (AR-02), ethyl acetate (AR-03), hexane (AR-04) and water (AR-05). The cytotoxicity was evaluated against three different human cancer cell lines, i.e. colon (DLD-1), lung (A-549), and breast (MCF-7) using Sulforhodamine B (SRB) assay along with non-cancerous VERO cells as control and doxorubicin (DOX) as positive control. As we observed strong cytotoxicity of AR-03 and AR-04 fractions against tested cells and marked cytotoxic effects particularly in colon cancer cell lines, we further re-fractionated, AR-03 into (AR-03A, AR-03B, AR-03C, AR-03D, AR-03E) and AR-04 into (AR-04A, AR-04B, AR-04C) sub-fractions by column chromatography and investigated against the same panel of cell lines in addition to one more colon cancer cell line (HT-29). Phytochemical analysis was performed through HPLC-ESI-QTOF-MS/MS fragmentation.ResultsEthyl acetate (AR-03) and hexane (AR-04) fractions were found to be the most cytotoxic against all the tested cell lines. Further, AR-03E and AR-04A sub-fractions were found more specific cytotoxic selectively against DLD-1 cancer cell lines at 100µg/ml concentration. HPLC-ESI-QTOF-MS/MS determination revealed the presence of 17 compounds in AR-01. Among them, 4 compounds were reported for the first time in this species. However, 3 identified compounds (artemorin, β-santonin and caryophyllene oxide) in AR-03E sub-fraction were commonly present in each bioactive fraction and may be considered as potential and safest cytotoxic agents for anticancer activity.ConclusionsExperimental evidences reported in this paper for anticancer activity validate the traditional wisdom of Artemisia nilagirica as an anticancer herbal drug. To our knowledge, this is our first novel observation of cytotoxicity and selectivity of ethyl acetate and hexane sub-fraction of AR-01 i.e. AR-03E and AR-04A respectively against DLD-1 human cancer cell lines. HPLC-ESI-QTOF-MS/MS determination attributes the identification of cytotoxic compounds which may be used for further preclinical studies.

Graphical abstract

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The Japanese Angelica acutiloba root and yokukansan increase hippocampal acetylcholine level, prevent apoptosis and improve memory in a rat model of repeated cerebral ischemia

Publication date: 25 March 2018
Source:Journal of Ethnopharmacology, Volume 214
Author(s): Ai Nogami-Hara, Masaki Nagao, Kotaro Takasaki, Nobuaki Egashira, Risako Fujikawa, Kaori Kubota, Takuya Watanabe, Shutaro Katsurabayashi, Funda Bolukbasi Hatip, Izzettin Hatip-Al-Khatib, Katsunori Iwasaki
Ethnopharmacological relevanceJapanese Angelica acutiloba root (Angelica root) is included in several Kampo medicines including Yokukansan (YKS). Angelica root and YKS are used for the treatment of a variety of psychological and neurodegenerative disorders. Development of safe and effective therapeutic agents against cerebrovascular disorders will improve the treatment of patients with dementia.Aim of the studyThe effect of Angelica root and YKS on ischemia-impaired memory has not yet been fully investigated. The present study investigated whether Angelica root is also involved in memory improving and neuroprotective effect of YKS in a model of cerebrovascular ischemia.Materials and methodsMale Wistar rats grouped into sham rats received saline, and other three groups subjected to repeated cerebral ischemia induced by 4-vessel occlusion (4-VO), received a 7-day oral administration of either saline, Angelica root or YKS. Memory was evaluated by eight-arm radial maze task. Acetylcholine release (ACh) in the dorsal hippocampus was investigated by microdialysis-HPLC. Apoptosis was determined by terminal deoxynucleotidyl transferase (TdT)-mediated fluorescein-deoxyuridine triphosphate (dUTP) nick-end labeling.ResultsIschemia induced apoptosis, reduced release of ACh, and impaired the memory (increased error choices and decreased correct choices). Angelica root and YKS improved the memory deficits, upregulated the release of ACh and prevented 4-VO-induced hippocampal apoptosis.ConclusionThe dual ACh-increasing and neuroprotective effect of Angelica root could make it a promising therapeutic agent useful for the treatment of symptoms of cerebrovascular dementia. Angelica root could be one of the components contributing to the memory-improving and neuroprotective effects of YKS.

Graphical abstract

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Editorial Board

Publication date: 1 March 2018
Source:Journal of Ethnopharmacology, Volume 213





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Folliculotropism in pigmented facial macules: Differential diagnosis with Reflectance confocal microscopy

Abstract

Pigmented facial macules are common on sun damage skin. The diagnosis of early stage lentigo maligna (LM) and lentigo maligna melanoma (LMM) is challenging. Reflectance confocal microscopy (RCM) has been proven to increase diagnostic accuracy of facial lesions.

A total 154 pigmented facial macules, retrospectively collected, were evaluate for the presence of already described RCM features and new parameters depicting aspects of the follicle .

Melanocytic nests, roundish pagetoid cells, follicular infiltration, bulgings from the follicles and many bright dendrites, and infiltration of the hair follicle (i.e. folliculotropism) were found to be indicative of LM/LMM compared to non-melanocytic skin neoplasms, with an overall sensitivity of 96% and specificity of 83%. Concerning non-melanocytic skin neoplasms, solar lentigo and lichen planus-like keratosis resulted better distinguishable from LM/LMM because usually lacking malignant features and presenting characteristic diagnostic parameters, such as cepidermal cobblestone pattern and polycyclic papillary contours. On the other hand, distinction of pigmented actinic keratosis (PAK) resulted more difficult, and needing evaluation of hair follicle infiltration and bulging structures, due to the frequent observation of few bright dendrites in the epidermis, but predominantly not infiltrating the hair follicle (estimated specificity for PAK 53%). .

A detailed evaluation of the components of the folliculotropism may help to improve the diagnostic accuracy. The classification of the type, distribution and amount of cells, and the presence of bulging around the follicles seem to represent important tools for the differentiation between PAK and LM/LMM at RCM analysis.

This article is protected by copyright. All rights reserved.

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Novel POFUT1 mutation associated with hidradenitis suppurativa-Dowling Degos Disease firm up a role for Notch signalling in the pathogenesis of this disorder: reply from authors

Abstract

We thank González-Villanueva et al. for their comments and commend them for their intriguing results. They report on a single patient with clinical and histopathological evidence for Dowling-Degos disease. In addition, the patient developed hidradenitis suppurativa. The patient was found to carry a mutation in POFUT1, a gene previously known to be associated with Dowling-Degos disease.

This article is protected by copyright. All rights reserved.

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The insular cortex and QTc interval in HIV+ and HIV− individuals: Is there an effect of sympathetic nervous system activity?

Publication date: January 2018
Source:Clinical Neurophysiology, Volume 129, Issue 1
Author(s): Michiaki Nagai, Keigo Dote, Masaya Kato, Noboru Oda




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Contents

Publication date: January 2018
Source:Clinical Neurophysiology, Volume 129, Issue 1





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High-resolution ultrasound in patients with Wartenberg’s migrant sensory neuritis, a case-control study

Publication date: January 2018
Source:Clinical Neurophysiology, Volume 129, Issue 1
Author(s): Ingrid J.T. Herraets, H. Stephan Goedee, Johan A. Telleman, Jan-Thies H. van Asseldonk, Leo H. Visser, W. Ludo van der Pol, Leonard H. van den Berg
ObjectiveWartenberg's migrant sensory neuritis (WMSN) is a rare, patchy, pure sensory neuropathy of unknown etiology. High-resolution ultrasonography (HRUS) is an emerging diagnostic technique for neuropathies, but it has not been applied in WMSN. In this study we aimed to determine HRUS abnormalities in WMSN.MethodsWe performed a case-control study of 8 newly diagnosed patients with WMSN and 22 treatment-naive disease controls (16 patients with pure sensory axonal neuropathy and 6 with pure sensory chronic inflammatory demyelinating polyneuropathy (CIDP) or Lewis-Sumner syndrome (LSS)). All patients underwent routine diagnostic evaluations and a predefined HRUS protocol.ResultsWe found multifocal nerve enlargement in all 8 WMSN patients. The median nerve in the upper arm and the sural nerve were significantly larger in WMSN than in axonal controls (p = 0.01 and p = 0.04). In CIDP/LSS, sonographic enlargement was more extensive. Furthermore we found brachial plexus involvement in 3 of 8 (38%) WMSN patients.ConclusionHRUS showed enlargement of multiple nerves in all WMSN patients even if clinical testing and NCS were normal.SignificanceThe feature of multifocal nerve enlargement may be of additional value in establishing the diagnosis of WMSN and may support the suggestion of an auto-immune etiology.



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Oxyneurography: A non-invasive NIRS technique to measure nerve oxygenation

Publication date: January 2018
Source:Clinical Neurophysiology, Volume 129, Issue 1
Author(s): Joe F. Jabre




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Neurophysiology and cognitive reserve: A promising path

Publication date: January 2018
Source:Clinical Neurophysiology, Volume 129, Issue 1
Author(s): Tarek K. Rajji




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Editorial Board

Publication date: January 2018
Source:Clinical Neurophysiology, Volume 129, Issue 1





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Bilateral early activity in the hip flexors associated with falls in stroke survivors: Preliminary evidence from laboratory-induced falls

Publication date: January 2018
Source:Clinical Neurophysiology, Volume 129, Issue 1
Author(s): Dmitrijs Celinskis, Mark D. Grabiner, Claire F. Honeycutt
ObjectiveFalls are the most common and expensive medical complication following stroke. Hypermetric reflexes have been suggested to impact post-stroke balance but no study has evaluated reflex amplitudes under real conditions of falls in this population. Our objective was to quantify the early reflexive responses during falls induced in the laboratory.MethodsSixteen stroke survivors were exposed to posteriorly directed treadmill perturbations that required a forward step to maintain a balance. Perturbations differed in terms of treadmill translation displacement, velocity, and acceleration. EMG amplitudes were compared between Fall/Recovery trials, as well as Fallers/Non-Fallers at two different time windows: 50–75 and 75–100 ms.ResultsSixteen of 86 trials resulted in falls by nine subjects (Fallers). While no differences were found between 50 and 75 ms, EMG amplitude in the paretic rectus femoris muscle was larger between 75 and 100 ms during Fall trials. Further, a bilateral increase in RF activity was seen in Fallers but not Non-Fallers. Interestingly, the bilateral increase was related to perturbation intensity (larger EMG activity with larger perturbations) in Fallers, but again not in Non-Fallers.ConclusionsHeightened early recovery hip flexor activity between 75 and 100 ms is associated with falls and Fallers post-stroke.SignificanceThough requiring replication and expanded subject pools, these preliminary results reflect a possible clinically meaningful relationship between heightened reflexive responses and fall risk. Future work should evaluate the underlying mechanisms driving these heightened reflexes (e.g. stretch, startle) such that future rehabilitation techniques can address this abnormal response.



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A method for the topographical identification and quantification of high frequency oscillations in intracranial electroencephalography recordings

Publication date: January 2018
Source:Clinical Neurophysiology, Volume 129, Issue 1
Author(s): Zachary J. Waldman, Shoichi Shimamoto, Inkyung Song, Iren Orosz, Anatol Bragin, Itzhak Fried, Jerome Engel, Richard Staba, Michael R. Sperling, Shennan A. Weiss
ObjectiveTo develop a reliable software method using a topographic analysis of time-frequency plots to distinguish ripple (80–200 Hz) oscillations that are often associated with EEG sharp waves or spikes (RonS) from sinusoid-like waveforms that appear as ripples but correspond with digital filtering of sharp transients contained in the wide bandwidth EEG.MethodsA custom algorithm distinguished true from false ripples in one second intracranial EEG (iEEG) recordings using wavelet convolution, identifying contours of isopower, and categorizing these contours into sets of open or closed loop groups. The spectral and temporal features of candidate groups were used to classify the ripple, and determine its duration, frequency, and power. Verification of detector accuracy was performed on the basis of simulations, and visual inspection of the original and band-pass filtered signals.ResultsThe detector could distinguish simulated true from false ripple on spikes (RonS). Among 2934 visually verified trials of iEEG recordings and spectrograms exhibiting RonS the accuracy of the detector was 88.5% with a sensitivity of 81.8% and a specificity of 95.2%. The precision was 94.5% and the negative predictive value was 84.0% (N = 12). Among, 1,370 trials of iEEG recording exhibiting RonS that were reviewed blindly without spectrograms the accuracy of the detector was 68.0%, with kappa equal to 0.01 ± 0.03. The detector successfully distinguished ripple from high spectral frequency 'fast ripple' oscillations (200–600 Hz), and characterize ripple duration and spectral frequency and power. The detector was confounded by brief bursts of gamma (30–80 Hz) activity in 7.31 ± 6.09% of trials, and in 30.2 ± 14.4% of the true RonS detections ripple duration was underestimated.ConclusionsCharacterizing the topographic features of a time-frequency plot generated by wavelet convolution is useful for distinguishing true oscillations from false oscillations generated by filter ringing.SignificanceCategorizing ripple oscillations and characterizing their properties can improve the clinical utility of the biomarker.



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