Παρασκευή 5 Ιανουαρίου 2018
Screening program in ovarian cancer: A logical step in clinical management? A meta-analysis
Source:Current Problems in Cancer
Author(s): Claudia Marchetti, Francesca De Felice, Giorgia Perniola, Francesca Lecce, Laura Vertechy, Marco Monti, Daniela Musio, Ludovico Muzii, Vincenzo Tombolini, Pierluigi Benedetti Panici
ObjectiveTreatment of ovarian cancer is a challenge and its poor prognosis still remains a problem of major importance. Due to the lack of early and specific symptoms, the vast majority of women are diagnosed with an advanced stage disease. The aim of this meta-analysis is to evaluate the impact of ovarian cancer screening program in asymptomatic women on clinical outcomes.Methods and materialA systematic literature electronic search was conducted in Pubmed, Medline, Scopus and ClinicalTrials.gov databases. Articles were selected with a systematic approach. Clinical trials concerning screening strategy compared with usual care in asymptomatic ovarian cancer women were considered, without any restrictions on the publication date. Trials were eligible if participants were asymptomatic and post-menopausal women. Outcomes included ovarian cancer diagnosis and disease specific mortality. The pooled relative risk was calculated using a fixed-effects model.ResultsOverall, three randomized controlled trials met inclusion criteria, totaling 353,590 asymptomatic women. In total 177,188 women were assigned to screening program, and 176,402 women were assigned to usual care. The risk of ovarian cancer diagnosis, both overall and at an early stage, was higher in screening group (relative risk 1.07, 95% confidence interval, 0.98–1.18; and relative risk 1.30, 95% confidence interval, 1.14–1.49, respectively). The relative risk for disease specific mortality was 0.96 (95% confidence interval, 0.85–1.10).ConclusionOur results suggest the possible benefit of ovarian cancer screening program in term of early stage diagnosis and reduced specific ovarian cancer mortality. Further studies of environmental and/or constitutional factors may lead to the identification of patient populations that could benefit from a screening program.
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Insights into insulin resistance, lifestyle and anthropometric measures of patients with prior colorectal cancer compared to controls: A National Health and Nutrition Examination Survey (NHANES) Study
Source:Current Problems in Cancer
Author(s): Kenneth Obi, Ramsey Mitchell, Alice Hinton, Peter Stanich, Darrell M. Gray, Somashekar Krishna, Samer El-Dika, Hisham Hussan
BackgroundInsulin resistance (IR) increases the risk of index colorectal cancer (CRC) development. Limited data exist on IR values, lifestyle and anthropometric alterations of patients after CRC diagnosis, a population at high risk for CRC recurrence.MethodsThis is a retrospective cohort study using the National Health and Nutrition Examination Survey (NHANES), 1999–2010. We identified patients with and without prior CRC above age 50. Our outcomes were lifestyle, anthropometric measures and insulin resistance measured using the triglyceride to high-density lipoprotein (TG/HDL) ratio and the homeostasis model assessment (HOMA-IR).ResultsThere were 146,841 patients with prior CRC and 26,979,507 without prior cancer (controls) in our cohort. Prior CRC patients were significantly older than controls (75.8 vs 62.3, p<0.01), however there were no significant differences in gender, ethnicity, income, caloric intake, tobacco use or alcohol consumption between both groups. Multivariate analysis revealed no difference between prior CRC patients and controls in TG/HDL ratio (Adjusted percent change = -2.17; 95% confidence interval [CI]: -27.96, 18.43) or HOMA-IR (Adjusted percent change = -6.85; 95% CI: -35.74, 15.90). Despite similar weight at age 25, prior CRC subjects had lower weights compared to controls (at time of NHANES survey, one and 10 years prior to survey and greatest weight). Furthermore prior CRC subjects gained less weight in the 10 years prior to survey.ConclusionPatients with prior CRC above age 50 have no conclusive evidence of increased insulin resistance compared to non-CRC controls. This is possibly due to lesser weight gain in the peri-CRC diagnosis or treatment period. Future efforts should focus on alternate etiologies for the increased CRC recurrence in this high risk group.
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Emerging facets in the treatment of patients with hepatopancreaticobiliary malignancies
Source:Current Problems in Cancer
Author(s): M.G. McNamara
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KLICK syndrome: an unusual phenotype
Erythrokeratoderma refers to a group of rare inherited disorders with both clinical and genetic heterogeneities.1 Lesions usually start in infancy and are characterized by localized and well-demarcated erythematous and hyperkeratotic plaques, sometimes with a migratory nature. Erythrokeratoderma is often inherited as an autosomal dominant trait caused by mutations in the genes GJB3, GJB4, or GJA1, encoding connexins 31, 30.3, and 43, respectively. Erythrokeratoderma may be associated with neurological anomalies and can be caused by ELOVL4.2 Recently, mutations in KDSR (3-ketodihydrosphingosine reductase), encoding an enzyme in the ceramide pathway were also demonstrated to lead to erythrokeratoderma.3
This article is protected by copyright. All rights reserved.
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Striate palmoplantar keratoderma resulting from a missense mutation in DSG1
palmoplantar keratodermas (PPKs, OMIM #144200) refer to a large phenotypically and genetically heterogeneous group of keratinisation disorders characterised by marked hyperkeratosis on the surface of the palms and soles.
This article is protected by copyright. All rights reserved.
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Long-term management of moderate-to-severe atopic dermatitis with dupilumab and concomitant topical corticosteroids (LIBERTY AD CHRONOS): a critical appraisal
Summary
Aim
Blauvelt et al. (The Lancet 2017; 389: 2287-303) aimed to compare the long-term efficacy and safety of dupilumab with medium-potency topical corticosteroids (TCS) versus placebo with TCS in adults with moderate-to-severe atopic dermatitis (AD).
Setting and design
This multicentre randomised, double-blinded, placebo-controlled trial was conducted in hospitals, clinics and academic institutions across 161 sites in 14 countries.
Study exposure
Adults with moderate-to-severe AD were randomly assigned (3:1:3) to receive subcutaneous dupilumab 300mg once weekly (qw) plus TCS, dupilumab 300mg every 2 weeks (q2w) plus TCS, or placebo plus TCS until week-52.
Primary outcome measures
Co-primary efficacy endpoints were patients (%) achieving Investigator's Global Assessment (IGA) 0/1 and 2-points or higher improvement from baseline, and Eczema Area and Severity Index 75% improvement from baseline (EASI-75) at week-16.
Results
740 patients were included in the trial: 319 were randomly assigned to dupilumab qw, 106 to dupilumab q2w and 315 to the placebo arm. At week-16, more patients in the dupilumab groups achieved the co-primary endpoints: IGA 0/1 (39% [125 patients] qw dosing, 39% [41 patients] q2w dosing vs 12% [39 patients] receiving placebo; p<0.0001) and EASI-75 (64% [204] and 69% [73] vs 23% [73]; p<0.0001). Whilst no new safety signals were identified, adverse effects (AEs) were noted in 261 (83%) in those receiving dupilumab qw plus TCS, 97 (88%) dupilumab q2w plus TCS and 266 (84%) for placebo plus TCS. Rates of conjunctivitis, injection site reactions and local herpes simplex infections were higher in the dupilumab groups compared with placebo.
Conclusions
Blauvelt et al. concluded that dupilumab treatment added to TCS improved AD up to week-52 compared with TCS alone, and also demonstrated acceptable safety.
This article is protected by copyright. All rights reserved.
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Pneumocephalus and seizures following combined spinal-epidural for labor
Most cases of pneumocephalus following neuraxial blocks are associated with accidental dural puncture using loss of resistance to air for identification of the epidural space [1]. To our knowledge, there are no published reports in literature following use of saline for loss of resistance. We report the finding of simultaneous pneumocephalus and a cavernoma in a patient who received a combined spinal-epidural analgesia for labor, using loss of resistance to saline (LORS). The patient provided written consent for the authors to publish this report.
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Nasotracheal intubation through pharyngeal flap after pharyngeal flap construction
A 24-year-old woman provided her written consent to publish the details of her case. She had undergone multiple surgeries including pharyngeal flap construction for bilateral cleft lip and palate. All previous operations were performed under general anesthesia by oral intubation. In the present procedure, sagittal split ramus osteotomy under general anesthesia with nasotracheal intubation was planned. We obtained the three-dimensional morphological structure of the pharyngeal flap (Fig. 1). The measurements of the cross-section at the narrowest were 5.1×12.8mm for the left orifice and 3.2×13.2mm for the right.
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Clinical experiences of unilateral anterior sub-costal quadratus lumborum block for a nephrectomy
Among several quadratus lumborum (QL) blocks, an anterior sub-costal QL block is a new technique, and there are only a few reports of this new approach in the literature [1,2]. In this case, we reported two cases in which we used the anterior sub-costal QL block for a nephrectomy.
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Clinical effects of prophylactic use of phentolamine in patients undergoing pheochromocytoma surgery
To the Editor,
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Emergency insertion of the LMA protector airway in patients in the lateral position
The LMAR Protector™ Airway (Teleflex Medical Japan, Tokyo, Protector), a new type of second generation airway, has an integrated cuff pressure indicator that allows continuous cuff pressure monitoring at a glance [1,2]. Continuous cuff pressure monitoring contributes to safe management in the perioperative period in all situations. Here, we report two cases in which the Protector was inserted in an emergency situation with the patient in the lateral position.
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Respiratory effect of interscalene brachial plexus block vs combined infraclavicular plexus block with suprascapular nerve block for arthroscopic shoulder surgery
Shoulder surgery typically results in moderate to severe postoperative pain, especially within the first 24h after surgery. The interscalene nerve block (ISB) is one of the most effective analgesic techniques for shoulder surgery. A common adverse effect after ISB remains the occurrence of ipsilateral phrenic nerve block. In the literature [1] diaphragm-sparing nerve blocks alternative to ISB for shoulder surgery, such as supraclavicular block, distal nerve blocks, intraarticular analgesia, has been reported; recently [2] a new combination of suprascapular nerve block (SSB) and infraclavicular block (ICB) seemed to provide surgical anesthesia and satisfactory postoperative analgesia, but, the respiratory effects of this technique are still not well documented.
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Under pressure: Evaluating the role of intraoperative hemodynamics in postoperative acute kidney injury
In this issue of Journal of Clinical Anesthesia, Wu et al. describe their well-designed randomized trial investigating the impact of targeted mean arterial pressure (MAP) ranges on postoperative acute kidney injury (AKI) [1]. Their study is of pressing concern: postoperative AKI remains a source of shared apprehension among anesthesiologists, surgeons, and nephrologists, for which prevention and treatment strategies are a matter of ongoing debate. The healthcare burden of postoperative AKI is well-described: it is common, costly, and life-threatening.
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Incidence of lower-extremity muscle weakness after quadratus lumborum block
Since the original publication on the quadratus lumborum (QL) block in 2013, various approaches for QL block administration have been reported [1,2]. Lower-extremity muscle weakness after a posterior QL block has been reported as a complication [3]. However, there have been no reports of lower-extremity muscle weakness after a QL block using other approaches. We investigated the incidence of lower-extremity muscle weakness after each type of QL block.
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Lack of generalizability of observational studies' findings for turnover time reduction and growth in surgery based on the State of Iowa, where from one year to the next, most growth was attributable to surgeons performing only a few cases per week
Three observational studies at large teaching hospitals found that reducing turnover times resulted in the surgeons performing more cases. We sought to determine if these findings are generalizable to other hospitals, because, if so, reducing turnover times may be an important mechanism for hospitals to use for growing caseloads.
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Lidocaine post-nasal dripping (LPND): An easy way for awake nasal intubation
Several techniques of topical anesthesia for awake fiberoptic intubation (AFOI) have been described such as "spray as you go" [1,2], nebulization [2], atomization [3,4] transtracheal injection [5]. These require multiple complicated steps [1,2], specialized equipment [2–4], and are invasive [5].
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Severe type B lactic acidosis and insulin-resistant hyperglycemia related to cadaveric kidney transplantation
Lactic acidosis, increased lactate levels >2mmol/L with a high anion gap metabolic acidosis, commonly occurs due to hypoperfusion/hypoxia (type A) but may also arise due to other causes, often overlooked, such as thiamine deficiency (type B) [1]. We report the perioperative occurrence of severe type B lactic acidosis with insulin-resistant hyperglycemia related to cadaveric kidney transplantation and its rapid resolution after intravenous thiamine administration. Written consent was obtained from the patient.
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Use of dexmedetomidine in a cardiac intensive care unit
Delirium, pain and agitation, known as the "triad of Intensive Care Units (ICU)" [1] are very common in critical patients. At least 20% of patients develop delirium during their stay in the ICU, reaching 80% in those receiving mechanical ventilation [2]. There is a need to identify these patients for appropriate treatment and prevention, as this neuronal dysfunction is associated with increased mortality, length of hospitalization, dependency and disability at discharge [3,4].
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Bilateral adductor canal block catheters in patients undergoing simultaneous bilateral knee arthroplasty: A series of 17 patients
Continuous adductor canal blocks (ACB) have been shown to reduce pain with knee flexion, decrease opioid consumption, and enhance ambulation following total knee arthroplasty [1]. Of the patients who undergo bilateral knee arthroplasties, a small subset have the procedures performed during the same operative encounter rather than a staged procedure [2]. These patients present additional perioperative pain and rehabilitation challenges, in addition to a longer length of hospital stay [2,3]. Adequate analgesia is imperative for immediate postoperative rehabilitation; however, there is a paucity of research regarding regional techniques for simultaneous bilateral knee arthroplasty (SBKA).
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Videolaryngoscope versus Macintosh laryngoscope for tracheal intubation in adults with obesity: A systematic review and meta-analysis
Videolaryngoscopy has become more common since the 2000s. Despite several anecdotal reports in the literature, it remains unclear whether videolaryngoscopy is superior to direct Macintosh laryngoscopy for tracheal intubation in adults with obesity. This systematic review and meta-analysis focused on prospective randomised trials comparing videolaryngoscopes with the Macintosh laryngoscope for tracheal intubation in adults with obesity.
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Retroclavicular approach to infraclavicular brachial plexus block for distal radius fracture in a patient with implanted pacemaker
Patients with implanted pacemaker underwent upper limb surgery under regional anesthesia in the literature are rarely. We report a case of successful retroclavicular approach to infraclavicular brachial plexus block (RA-IBPB) in a patient with implanted pacemaker and with requiring open osteosynthesis due to distal radius fracture.
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Anesthetic management for laparoscopic sleeve gastrectomy to a child
Anesthesia for obese children undergoing weight loss surgery poses a challenge for the anesthetists given that this population has high risk of developing psychosocial and medical comorbidities such as pulmonary and cardiovascular disorders, hypertension, dyslipidemia, obstructive sleep apnea and type 2 diabetes mellitus [1–3].
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Ketorolac dose-response for acute pain is well known and the safety rules for adequate prescribing are clear
The study by Duttchen et al. [1] shows almost no difference in analgesic efficacy when comparing 15 and 30mg of IV ketorolac given intraoperatively to provide postoperative pain relief. In the discussion, the authors indicate that another 2017 study performed in an emergency department similarly showed that in patients with acute pain 10, 15 and 30mg are of similar analgesic efficacy [2], suggesting that these data are new.
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Takotsubo cardiomyopathy complicating thoracoabdominal aortic aneurysm repair
We describe the management of a patient with symptomatic spinal cord hypoperfusion after thoracoabdominal aortic aneurysm repair, where the neurological insult and associated emotional stress precipitated Takotsubo cardiomyopathy. Transthoracic Echocardiography showed akinetic mid and apical left ventricular segments, while basal segments were spared. Emergent coronary angiography ruled out acute coronary syndrome. Excess catecholamines have been postulated as a contributing mechanism to the disease, therefore, catecholamines were avoided to prevent further myocardial injury.
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Preliminary Clinical Experience with a Combined Automated Breast Ultrasound and Digital Breast Tomosynthesis System
Source:Ultrasound in Medicine & Biology
Author(s): Eric D. Larson, Won-Mean Lee, Marilyn A. Roubidoux, Mitchell M. Goodsitt, Chris Lashbrook, Cynthia E. Davis, Oliver D. Kripfgans, Paul L. Carson
We analyzed the performance of a mammographically configured, automated breast ultrasound (McABUS) scanner combined with a digital breast tomosynthesis (DBT) system. The GE Invenia ultrasound system was modified for integration with GE DBT systems. Ultrasound and DBT imaging were performed in the same mammographic compression. Our small preliminary study included 13 cases, six of whom had contained invasive cancers. From analysis of these cases, current limitations and corresponding potential improvements of the system were determined. A registration analysis was performed to compare the ease of McABUS to DBT registration for this system with that of two systems designed previously. It was observed that in comparison to data from an earlier study, the McABUS-to-DBT registration alignment errors for both this system and a previously built combined system were smaller than those for a previously built standalone McABUS system.
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MiR-449a suppresses cell migration and invasion by targeting PLAGL2 in breast cancer
Publication date: Available online 5 January 2018
Source:Pathology - Research and Practice
Author(s): Bin Xu, Xiping Zhang, Shanshan Wang, Bailing Shi
BackgroundBreast cancer is one of the most common malignancies worldwide. However, the detailed molecular mechanisms underlying breast cancer metastasis are still incompletely clear. MicroRNAs (miRNAs) play a crucial role in cancer metastasis. In this study, we aimed to analyze the expression and function of miR-449a in breast cancer.Material and MethodsA total of 15 human primary breast cancer tissues and adjacent non-cancerous tissues (10 pairs) were obtained. MiR-449a was examined in tumor tissues and adjacent nontumorous tissues of breast cancer patients and cell lines by real-time PCR. The protein expression levels were analyzed by western blot and immunohistochemistry staining. Luciferase reporter assays was used to validate the target of miR-449a. The effect of miR-449a on breast cancer cell migration and invasion were studied in vitro and in vivo.ResultsThe expression levels of miR-449a were significantly decreased in breast cancer tissues and cell lines. Overexpression of miR-449a suppressed breast cancer cell proliferation, clone formation, migration, invasion and metastasis in vitro and in vivo. Pleomorphic adenoma gene like-2 (PLAGL2) was identified as a major target of miR-449a. Both overexpression of miR-449a inhibited the expression of PLAGL2 significantly and the knockdown of PLAGL2 expression inhibited the breast cancer cell proliferation and metastasis.ConclusionWe demonstrate the miR-449a tumor suppressor role in breast cancer cell migration and invasion via targeting PLAGL2. These findings suggesting that miR-449a/PLAGL2 could serve as a therapeutic strategy for targeting breast cancer.
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Process-induced morphology and mechanical properties of high-density polyethylene
Publication date: 31 January 2018
Source:Polymer, Volume 136
Author(s): Regine Boldt, Uwe Gohs, Udo Wagenknecht, Manfred Stamm
Electron induced reactive processing (EIReP) is an emerging technology for the development of high performance polymer materials. It simultaneously combines the traditional electron beam (EB) treatment of polymers and their melt mixing in the presence of shear stresses and/or rates of deformation. In comparison to traditional EB treatment of high-density polyethylene (HD-PE) at room temperature, EIReP modified HD-PE shows an inhomogeneous morphology, a self-nucleation effect as well as a significant increased tensile strength and decreased elongation at break. In order to identify the reason of these changed properties and the working principle of EIReP, HD-PE has been modified by EB treatment in solid and molten state as well as before and after the presence of shear stresses and/or rates of deformation. Shear stresses and/or rates of deformation were applied during injection moulding of tensile specimens. Based on results of previous work the EB treatments and EIReP of HD-PE were performed under nitrogen atmosphere in order to reduce oxygen induced side reactions. The process induced morphological and mechanical properties have been investigated using optical light microscopy, transmission electron microscopy as well as thermal analysis and tensile tests. Changes of molecular mass were measured with size exclusion chromatography and confirmed by rheological measurements. The results demonstrate that the morphology and specific tensile properties of HD-PE were only changed by an EB treatment before the influence of shear stresses and/or rates of deformation on EB modified HD-PE during injection moulding. In addition, the state of aggregate during EB treatment has no influence on morphology and tensile properties. Consequently, the EIReP induced effect based on electron induced changes of HD-PE molecular structure and the subsequent influence of shear stresses and/or rates of deformation.
Graphical abstract
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Screening of GLE1 mutations in Chinese amyotrophic lateral sclerosis patients
Publication date: Available online 5 January 2018
Source:Neurobiology of Aging
Author(s): Kang Zhang, Qing Liu, Dongchao Shen, Hongfei Tai, Hanhui Fu, Shuangwu Liu, Jinyi Chen, Xiaoguang Li, Mingsheng Liu, Xue Zhang, Liying Cui
Amyotrophic lateral sclerosis (ALS) is a lethal neurological disease primarily involving the spinal cord, brainstem, and corticospinal tract. Recently, mutations in the GLE1 gene were reported in Caucasian ALS patients. To inquire whether Chinese ALS patients carried causal mutations in the gene, we screened all 16 coding exons of GLE1 with Sanger sequencing in a Han Chinese cohort of 250 ALS cases. No nonsynonymous coding variants was detected. Our results suggest that pathogenic variants in the GLE1 gene are rare in Chinese ALS patients.
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Interdependence of bacterial cell division and genome segregation and its potential in drug development
Source:Microbiological Research
Author(s): Hari S. Misra, Ganesh K. Maurya, Reema Chaudhary, Chitra S. Misra
Cell division and genome segregation are mutually interdependent processes, which are tightly linked with bacterial multiplication. Mechanisms underlying cell division and the cellular machinery involved are largely conserved across bacteria. Segregation of genome elements on the other hand, follows different pathways depending upon its type and the functional components encoded on these elements. Small molecules, that are known to inhibit cell division and/or resolution of intertwined circular chromosome and maintenace of DNA topology have earlier been tested as antibacterial agents. The utility of such drugs in controlling bacterial infections has witnessed only partial success, possibly due to functional redundancy associated with targeted components. However, in due course, literature has grown with newer information. This review has brought forth some recent findings on bacterial cell division with special emphasis on crosstalk between cell division and genome segregation that could be explored as novel targets in drug development.
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TMS of primary motor cortex with a biphasic pulse activates two independent sets of excitable neurones
Source:Brain Stimulation
Author(s): Martin Sommer, Matteo Ciocca, Raffaella Chieffo, Paul Hammond, Andreas Neef, Walter Paulus, John C. Rothwell, Ricci Hannah
BackgroundBiphasic pulses produced by most commercially available TMS machines have a cosine waveform, which makes it difficult to study the interaction between the two phases of stimulation.ObjectiveWe used a controllable pulse TMS (cTMS) device delivering quasi-rectangular pulse outputs to investigate whether monophasic are more effective than biphasic pulses.MethodsTemporally symmetric ("biphasic") or highly asymmetric ("monophasic") charge-balanced biphasic stimuli were used to target the hand area of motor cortex in the anterior-posterior (AP) or posterior-anterior (PA) initial current direction.ResultsWe observed the lowest motor thresholds and shortest motor evoked potential (MEP) latencies with initial PA pulses, and highest thresholds and longest latencies with AP pulses. Increasing pulse symmetry tended to increase threshold with a PA direction whereas it lowered thresholds and shortened latencies with an AP direction. Furthermore, it steepened the MEP input-output curve with both directions.Conclusions"Biphasic" TMS pulses can be viewed as two monophasic pulses of opposite directions, each stimulating a different set of interneurons with different thresholds (PA < AP). At threshold, the reverse phase of an initially PA pulse increases threshold compared with "monophasic" stimulation. At higher intensities, the reverse phase begins to activate AP-sensitive neurones and increase the effectiveness of stimulation above that of a "monophasic" PA pulse. "Biphasic" stimulation with initially AP pulses is dominated at threshold by activation produced by the lower threshold reverse (PA) phase.SignificanceThe effects of biphasic stimulation are best understood as the summed output of two independent sets of directionally selective neural populations.
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Sensitive fluorescence sensing of T4 polynucleotide kinase activity and inhibition based on DNA/polydopamine nanospheres platform
Publication date: 1 April 2018
Source:Talanta, Volume 180
Author(s): Yao Cen, Wen-Jing Deng, Ru-Qin Yu, Xia Chu
5′-Polynucleotide kinase (PNK) is a crucial enzyme that catalyzes the phosphorylation of nucleic acid with 5′-OH termini and this phosphorylation reaction has been involved in many important cellular activities. The evaluation of PNK activity has received an increasing attention due to the significance of PNK. Here, the polydopamine nanospheres (PDANS) could adsorb single-stranded DNA (ssDNA) through π–π stacking or hydrogen bonding between nucleobases and aromatic groups of PDANS, while the interaction between double-stranded DNA (dsDNA) with PDANS was weakened due to the changed conformation. Hence, a novel DNA/PDANS platform was constructed for the sensitive and selective determination of T4 PNK activity based on the preferential binding properties of PDANS for ssDNA over dsDNA and the excellent fluorescence quenching property of PDANS. The dye-labeled dsDNA was phosphorylated by T4 PNK and then digested by λ exonuclease, yielding dye-labeled ssDNA, which would be adsorbed on the surface of the PDANS and the fluorescence was greatly quenched by PDANS. Because of the preferential binding properties of PDANS for ssDNA over dsDNA and the high quenching property of PDANS, the developed DNA/PDANS platform exhibited good analytical performance for T4 PNK sensing in complex biological matrix and applied to screening inhibitors. The proposed DNA/PDANS based platform is promising in developing high-throughput assays for drug screening and clinical diagnostics.
Graphical abstract
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A highly selective, colorimetric and ratiometric fluorescent probe for NH2NH2 and its bioimaging
Publication date: 1 April 2018
Source:Talanta, Volume 180
Author(s): Hai Xu, Biao Gu, Yaqian Li, Zhen Huang, Wei Su, Xiaoli Duan, Peng Yin, Haitao Li, Shouzhuo Yao
In this work, we report a novel approach which employed substrate-triggered intramolecular addition-cyclization cascade to develop a highly selective fluorescent probe E)-3-(4-(1H-phenanthro[9,10-d]imidazol-2-yl)phenyl)-1-(2-hydroxylphenyl) prop-2-en-1-one (P-OH) for NH2NH2. The new sensing mechanism of P-OH for NH2NH2 was investigated in detail by fluorescence spectroscopy, 1H NMR titration, mass spectrometry and control experiments. The synthesized probe showed ratiometric fluorescent response to NH2NH2 with naked-eye color changes from yellow to colorless. It's noteworthy that this probe displayed high sensitivity and selectivity to NH2NH2 over other species, including primary amines, Cys, Hcy, GSH, HS- and HSO3-. Furthermore, the probe can not only detect NH2NH2 in real water samples but also image NH2NH2 in living cells, indicating its potential utility for NH2NH2 sensing in environmental and biological samples.
Graphical abstract
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Rapid and interference-free analysis of nine B-group vitamins in energy drinks using trilinear component modeling of liquid chromatography-mass spectrometry data
Publication date: 1 April 2018
Source:Talanta, Volume 180
Author(s): Yong Hu, Hai-Long Wu, Xiao-Li Yin, Hui-Wen Gu, Rong Xiao, Li-Xia Xie, Zhi Liu, Huan Fang, Li Wang, Ru-Qin Yu
The aim of the present work was to develop a rapid and interference-free method based on liquid chromatography-mass spectrometry (LC-MS) for the simultaneous determination of nine B-group vitamins in various energy drinks. A smart and green strategy that modeled the three-way data array of LC-MS with second-order calibration methods based on alternating trilinear decomposition (ATLD) and alternating penalty trilinear decomposition (APTLD) algorithms was developed. By virtue of "mathematical separation" and "second-order advantage", the proposed strategy successfully solved the co-eluted peaks and unknown interferents in LC-MS analysis with the elution time less than 4.5min and simple sample preparation. Satisfactory quantitative results were obtained by the ATLD-LC-MS and APTLD-LC-MS methods for the spiked recovery assays, with the average spiked recoveries ranging from 87.2–113.9% to 92.0–111.7%, respectively. These results acquired from the proposed methods were confirmed by the LC-MS/MS method, which shows a quite good consistency with each other. All these results demonstrated that the developed chemometrics-assisted LC-MS strategy had advantages of being rapid, green, accurate and low-cost, and it could be an attractive alternative for the determination of multiple vitamins in complex food matrices, which required no laborious sample preparation, tedious condition optimization or more sophisticated instrumentations.
Graphical abstract
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Trends of non-destructive analytical methods for identification of biodiesel feedstock in diesel-biodiesel blend according to European Commission Directive 2012/0288/EC and detecting diesel-biodiesel blend adulteration: A brief review
Publication date: 1 April 2018
Source:Talanta, Volume 180
Author(s): Sarmento Júnior Mazivila
Discrimination of biodiesel feedstock present in diesel-biodiesel blend is challenging due to the great similarity in the spectral profile as well as digital image profile of each type of feedstock employed in biodiesel production. Once the marketed diesel-biodiesel blend is subsidized, in which motivates adulteration in biofuel blend by cheaper supplies with high solubility to obtain profits associated with the subsidies involved in biodiesel production. Non-destructive analytical methods based on qualitative and quantitative analysis for detecting marketed diesel-biodiesel blend adulteration are reviewed. Therefore, at the end is discussed the advantage of the qualitative analysis over quantitative analysis, when the systems require immediate decisions such as to know if the marketed diesel-biodiesel blend is unadulterated or adulterated in order to aid the analyst in selecting the most appropriate green analytical procedure for detecting diesel-biodiesel blend adulteration proceeding in fast way. This critical review provides a brief review on the non-destructive analytical methods reported in scientific literature based on different first-order multivariate calibration models coupled with spectroscopy data and digital image data to identify the type of biodiesel feedstock present in diesel-biodiesel blend in order to meets the strategies adopted by European Commission Directive 2012/0288/EC as well as to monitoring diesel-biodiesel adulteration. According to that Directive, from 2020 biodiesel produced from first-generation feedstock, that is, oils employed in human food such as sunflower, soybean, rapeseed, palm oil, among other oils should not be subsidized. Therefore, those non-destructive analytical methods here reviewed are helpful for discrimination of biodiesel feedstock present in diesel-biodiesel blend according to European Commission Directive 2012/0288/EC as well as for detecting diesel-biodiesel blend adulteration.
Graphical abstract
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Ultrasensitive electrochemical detection of poly (ADP-ribose) polymerase-1 via polyaniline deposition
Publication date: 1 April 2018
Source:Talanta, Volume 180
Author(s): Yong Liu, Jiahui Fan, Li Shangguan, Yuanjian Liu, Yuanqing Wei, Wei Wei, Songqin Liu
Recent findings have thrust poly ADP (ADP: adenosine diphosphate)-ribose polymerase-1 (PARP-1) into the limelight as potential chemotherapeutic target because it is closely related to the development of tumor. So, studies on its detection and inhibitors evaluation have attracted more attention. It is interesting that poly (ADP-ribose) (PAR), the catalytic product of PARP-1 in the existence of nicotinamide adenine dinucleotide (NAD+), possess twice charge density of DNA strands. PAR contain 200 units, i.e., about 400bp bases, and multiple branched strands. So, plentiful negative charges on PAR supplied exquisite environment for PANI deposition, which was triggered by horseradish peroxidase (HRP). Because of the unique electrochemical property of PANI, ultrasensitive electrochemical detection of PARP-1 was proposed. Under optimum conditions, DPV intensity linearly increased with the increment of PARP-1 in the range of 0.005–1.0 U. The detection limit was 0.002 U, which was comparable or more sensitive than that obtained from previously reported strategies.
Graphical abstract
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Silica nanoparticles coated by poly(acrylic acid) brushes via host-guest interactions for detecting DNA sequence of Hepatitis B virus
Publication date: 1 May 2018
Source:Talanta, Volume 181
Author(s): Lu Ding, Chunlan Xiang, Gang Zhou
Poly(acrylic acid) (PAA) brushes coated onto silica nanoparticles have been widely utilized in bioassays due to their abilities of providing favorable microenvironments and ensuring good biological activities for biomolecules. However, traditional PAA brushes are synthesized by reversible addition–fragmentation chain transfer polymerization. Hence, it is generally difficult to control and characterize the molecular weight of the PAA brushes, which may depress the reproducibility and bring more uncertain results. Herein, atom transfer radical polymerization method is employed to synthesize β-cyclodextrin-cored PAA with uniform and controllable molecular weight. After loading on the surfaces of adamantane-functionalized silica nanoparticles via host-guest interactions, glucose oxidase and probe single strand DNA (ssDNA) are further immobilized on the as-prepared nanoparticles. Meanwhile, capture ssDNA is functionalized on amino modified magnetic beads. In the presence of ssDNA sequence of Hepatitis B Virus (HBV) containing completely matched sequence of both probe and capture ssDNA, a bioconjugate is formed and can be separated by an external magnet. The isolated glucose oxidase can further catalyze glucose into gluconic acid and H2O2, and then reduce HAuCl4 on Au seeds. By monitoring the absorption intensity change of the Au NPs at 530nm, the proposed biosensor with novel signal amplification probes can be used to detect DNA sequence of HBV with high sensitivity and selectivity in both buffer and serum samples. This developed strategy has presented a new way to construct silica nanoparticles coated by PAA brushes for the fields of clinical diagnosis and other life sciences.
Graphical abstract
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A sensitive SPR biosensor based on hollow gold nanospheres and improved sandwich assay with PDA-Ag@Fe3O4/rGO
Publication date: 1 April 2018
Source:Talanta, Volume 180
Author(s): Shuo Li, Qiong Wu, Pinyi Ma, Yue Zhang, Daqian Song, Xinghua Wang, Ying Sun
A novel surface plasmon resonance (SPR) biosensor based on hollow gold nanospheres (HGNPs) and an improved sandwich assay was developed to detect rabbit IgG. The electromagnetic coupling between the HGNPs and Au film, and the notable plasmonic fields spread over the inner and outer surfaces of HGNPs, led to the considerable amplification of the SPR signal. Polydopamine-Ag@Fe3O4/reduced graphene oxide (PDA-Ag@Fe3O4/rGO) was introduced to bind detection antibody (Ab2) to form the improved sandwich structure. Ag nanoparticles were excited to produce SPR and their hot electrons were doped on graphene thin films, which amplified the response of biomolecules. Magnetic nanoparticles (Fe3O4) simplified the collection of Ab2-PDA-Ag@Fe3O4/rGO. An external layer of polydopamine (PDA) permitted the efficient immobilization of Ab2 without activation via abundant functional groups and protected the nanoparticles from etching or agglomeration. In addition, because of its large mass, Ab2-PDA-Ag@Fe3O4/rGO also played a key role in the further amplification of the SPR response signals. This novel SPR biosensor exhibited an effective response to the rabbit IgG at the different concentrations ranging from 0.019 to 40.00μgmL−1. This value is 132 times lower than that observed for a traditional SPR biosensor based on Au-3-mercaptopropionic acid and 8 times lower than that obtained from an Ab2 sandwich assay, which indicates that the SPR sensor has high sensitivity. In addition, the designed biosensor showed satisfactory recoveries to detect the rabbit IgG spiked in serum samples. Therefore, the novel SPR biosensor with high sensitivity and acceptable recovery has potential for practical applications.
Graphical abstract
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The synthesis of a smart streptavidin-functionalized poly(N-isopropylacrylamide) composite and its application in the separation and detection of virus nucleic acid
Publication date: 1 May 2018
Source:Talanta, Volume 181
Author(s): Xinxin Wang, Mingyuan Du, Guobin Mao, Jiao Zheng, Jinyang Chen, Xinghu Ji, Zhike He
A new kind of polymeric material (PNIPAAm-co-SA) was prepared by conjugating a thermosensitive polymer, Poly (N-isopropylacrylamide) (PNIPAAm) with streptavidin (SA). This smart prepared composite displayed a controllable conformation change between an expanded and a collapsed form, below or above its lower critical solution temperature (LCST). Differential scanning calorimetry (DSC) analysis demonstrated that the PNIPAAm-co-SA bioconjugate showed the same LCST as the original synthetic polymer, PNIPAAm, which was also 32°C. Based on the specific interaction between SA and biotin, a higher capture efficiency of PNIPAAm-co-SA, which was almost 100% in PBS buffer solution and above 70% in serum was obtained, respectively. And the high affinity between PNIPAAm-co-SA and biotin was still maintained after three heating cycles. Subsequently, the variola virus (small pox, VV) oligonucleotide sequence was chosen as a model to demonstrate the sensitivity of the biosensor which was fabricated based on PNIPAAm-co-SA. The biosensor exhibited the ability to separate and enrich targets from complicated system with its phase transition ability, and high sensitivity toward VV-targets were achieved. Moreover, other types of targets such as proteins and cells, could be detected by changing the biotin-captures, which indicated the broad applicability of biosensors based on this smart polymer material.
Graphical abstract
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An electrochemical sensor based on copper-based metal-organic frameworks-graphene composites for determination of dihydroxybenzene isomers in water
Publication date: 1 May 2018
Source:Talanta, Volume 181
Author(s): Jun Li, Jianfei Xia, Feifei Zhang, Zonghua Wang, Qingyun Liu
A highly and simply sensitive electrochemical sensor was presented for the simultaneous determination of hydroquinone (HQ) and catechol (CT) in the water based on copper centered metal-organic framework-graphene composites (Cu-MOF-GN) [Cu-MOF = Cu3(BTC)2 (BTC = 1, 3, 5-benzenetricarboxylicacid)] modified glassy carbon electrode (Cu-MOF-GN/GCE). The modification procedure was carried out through casting metal-organic framework-graphene oxide composites (Cu-MOF-GO) on the bare glassy carbon electrode and followed by the transformation of Cu-MOF-GO to Cu-MOF-GN by an electrochemical reduction. The electrochemical behavior of HQ and CT at Cu-MOF-GN/GCE was investigated by cyclic voltammetry (CV), differential pulse voltammetry (DPV) and electrochemical impedance spectroscopy (EIS). Under the optimized conditions, the modified electrode had excellent electrocatalytic activity and high selectivity toward HQ and CT. The electrochemical sensor exhibited a linear response in the same range of 1.0 × 10−6 to 1.0 × 10−3M with the detection limits of 5.9 × 10−7M for HQ and 3.3 × 10−7M for CT (S/N = 3). Four samples of tap water spiked with different concentrations of HQ and CT were considered. The method has been applied to the analysis of these isomers in spiked tap water with recoveries from 99.0 ~ 102.9% and relative standard deviations (RSDs) for 5 successive measurements less than 5% were also acceptable. This method was successfully applied to detect target analytes in the real samples with satisfying results. The MOFs-based sensors in the field of electrochemical sensing held a great promise for routine sensing applications.
Graphical abstract
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Particle-based immobilized enzymatic reactors in microfluidic chips
Publication date: 1 April 2018
Source:Talanta, Volume 180
Author(s): Adam Kecskemeti, Attila Gaspar
The research and applications of immobilized enzyme reactors (IMERs) have become more and more widespread due to the numerous advantages like reusability, easy handling, prolonged lifetime, easy separation from products and substrate specificity. The miniaturized form of these reactors (microchip IMERs) received outstanding attention due to their special features and advantages over the traditional, larger analytical systems. Large specific surface is essential for the efficient operation of the microreactors, thus these devices include one of the several types of porous solid supports, but in this work only the particle based microchip IMERs are reviewed. A very large variety of micro- or nanoparticles (beads) have been used in the microchip IMERs, however, incorporating these particles into microchips is still a challenge, because the common procedures used for the preparation of chromatographic columns are not well applicable at the microscopic level.Many detection systems were applied with microchip IMERs using on-chip or off-chip arrangement. The combination of microchip IMERs with mass spectrometry is particularly popular, because in these systems high-throughput analysis can be achieved by which the proteomic studies can be largely accelerated. In most chip IMER-MS systems, the chips are used for sample pretreatment including analyte (protein) digestion, preconcentration of analyte, removal of matrix materials. Additional applications of the IMERs - like the rapid protein digestion with proteolytic enzymes, the transformation of analytes to a more easily or more sensitively measurable form (detection signal amplification) and the design of microarrays/biosensors to analyze antigens based on specific interactions in immunoanalytical studies – are also reviewed.
Graphical abstract
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A chemometric approach for characterization of serum transthyretin in familial amyloidotic polyneuropathy type I (FAP-I) by electrospray ionization-ion mobility mass spectrometry
Publication date: 1 May 2018
Source:Talanta, Volume 181
Author(s): Laura Pont, Victoria Sanz-Nebot, Marta Vilaseca, Joaquim Jaumot, Roma Tauler, Fernando Benavente
In this study, we describe a chemometric data analysis approach to assist in the interpretation of the complex datasets from the analysis of high-molecular mass oligomeric proteins by ion mobility mass spectrometry (IM-MS). The homotetrameric protein transthyretin (TTR) is involved in familial amyloidotic polyneuropathy type I (FAP-I). FAP-I is associated with a specific TTR mutant variant (TTR(Met30)) that can be easily detected analyzing the monomeric forms of the mutant protein. However, the mechanism of protein misfolding and aggregation onset, which could be triggered by structural changes in the native tetrameric protein, remains under investigation. Serum TTR from healthy controls and FAP-I patients was purified under non-denaturing conditions by conventional immunoprecipitation in solution and analyzed by IM-MS. IM-MS allowed separation and characterization of several tetrameric, trimeric and dimeric TTR gas ions due to their differential drift time. After an appropriate data pre-processing, multivariate curve resolution alternating least squares (MCR-ALS) was applied to the complex datasets. A group of seven independent components being characterized by their ion mobility profiles and mass spectra were resolved to explain the observed data variance in control and patient samples. Then, principal component analysis (PCA) and partial least squares discriminant analysis (PLS-DA) were considered for exploration and classification. Only four out of the seven resolved components were enough for an accurate differentiation. Furthermore, the specific TTR ions identified in the mass spectra of these components and the resolved ion mobility profiles provided a straightforward insight into the most relevant oligomeric TTR proteoforms for the disease.
Graphical abstract
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A polyethyleneimine-modified attapulgite as a novel solid support in matrix solid-phase dispersion for the extraction of cadmium traces in seafood products
Publication date: 1 April 2018
Source:Talanta, Volume 180
Author(s): Tingting Wang, Yihui Chen, Junfeng Ma, Zhenfeng Jin, Mengsa Chai, Xunwen Xiao, Lihua Zhang, Yukui Zhang
In current study, a new polyethyleneimine (PEI)-modified attapulgite material was prepared serving as a solid support in matrix solid-phase dispersion for the extraction and determination (by atomic absorption spectrometry) of cadmium in seafood products. The major factors affecting PEI grafting were optimized using various PEI amounts and molecular weights. Parameters pivotal to MSPD extraction efficiency, like: pH, volume of eluting solvent, and the sorbent mass-to-sample ratio were investigated. Quantitative recoveries were achieved with 0.21g of fish sample, 0.13g of PEI-modified attapulgite dispersing agent, and 50% HNO3 eluting solution. The limit of detection and the limit of quantification were found to be 2.5 and 8.3μgkg−1 for cadmium in surimi samples, respectively. The recoveries were in the range of 89.2–100.1%, with RSDs ranged from 3.0% to 7.9% (n = 5). When compared to the method stipulated by the Chinese National Standard GB 5009.15-2014, the newly developed MSPD provides comparable accuracy and even better repeatability for the analysis of the cadmium in real seafood samples.
Graphical abstract
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Upconversion particle@Fe3O4@molecularly imprinted polymer with controllable shell thickness as high-performance fluorescent probe for sensing quinolones
Publication date: 1 May 2018
Source:Talanta, Volume 181
Author(s): Yiwei Tang, Huan Liu, Jingwen Gao, Xiuying Liu, Xue Gao, Xiaonan Lu, Guozhen Fang, Junping Wang, Jianrong Li
Localized photo-polymerization was ingeniously applied to prepare a multifunctional molecularly imprinted polymer (MIP) fluorescent probe using the "layer-by-layer" assembly of MIP and Fe3O4 nanoparticles on NaYF4: Yb3+, Er3+ upconversion particles (MUCPs@MIP). Enrofloxacin was used as the template and chosen as the target molecular during the investigation of the adsorption property. This ternary probe has magnetic and broad-spectrum molecular recognition capability, fast response, and upconversion fluorescence. The results of the fluorescence quenching analysis showed good linear ranges of 1.03nmol/L to 0.28μmol/L for enrofloxacin, 1.69nmol/L to 0.22μmol/L for fleroxacin, 6.92nmol/L to 0.28μmol/L for levofloxacin, 7.54nmol/L to 0.30μmol/L for ciprofloxacin, and 3.90nmol/L to 0.25μmol/L for enoxacin. This probe was further used to determine five quinolones in fish tissues and the recoveries ranging from 90.33% to 108.43% were obtained with relative standard deviation below 5.53%. This work offers a new and general strategy to synthesize a MUCPs@MIP upconversion fluorescence probe with magnetic and selective molecular recognition capability for rapid and accurate sensing of multiple chemical residues in the environment and agri-food products.
Graphical abstract
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Thrombodynamics, a new global coagulation test: Measurement of heparin efficiency
Publication date: 1 April 2018
Source:Talanta, Volume 180
Author(s): Elena I. Sinauridze, Tatiana A. Vuimo, Ivan D. Tarandovskiy, Ruzanna A. Ovsepyan, Stepan S. Surov, Natalia G. Korotina, Ilya I. Serebriyskiy, Maxim M. Lutsenko, Alexander L. Sokolov, Fazoil I. Ataullakhanov
The actual coagulation status may be reliably measured using only highly sensitive global functional tests; however, they are not numerous and all of them have disadvantages. Thrombodynamics (TD), a novel global coagulation test, is sensitive to hypo- and hypercoagulable states. The main properties of this test were investigated, and its capabilities for hemostasis analysis were verified through pharmacodynamic monitoring of the most widely used anticoagulants, heparins. The anticoagulant effects in the plasma of donors (n = 20) and patients after hip replacement (n = 20) spiked with unfractionated heparin or enoxaparin were measured in vitro to eliminate the influence of pharmacokinetic factors. Sensitivity for heparins was compared for activated partial thromboplastin time, thrombin generation tests and TD. TD was shown to reliably characterize the pharmacodynamics of any heparin in the entire range of its prophylactic and therapeutic concentrations. Inter-individual variability for the anticoagulant action of heparins was also calculated using the TD data. This variability did not differ between the investigated groups and did not exceed 12% and 20% for the stationary clot growth rate in the presence of unfractionated heparin and enoxaparin, respectively. That finding was in accordance with the values determined earlier using the thrombin generation test. The study results showed that TD has advantages over the other global methods of coagulation analysis. These advantages are good standardization, high reproducibility, independence of the parameter values from patient age and gender, and a narrower parameter distribution in a normal population. These results indicate that TD is a promising universal assessment method that improves the quality of hemostasis analysis because it more reliably detects deviations from the parameters' reference values.
Graphical abstract
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Recent advances and developments on integrating nanotechnology with chemiluminescence assays
Publication date: 1 April 2018
Source:Talanta, Volume 180
Author(s): Ashish Tiwari, S.J. Dhoble
Chemiluminescence (CL) techniques are extensively utilized for detection of analytes due to their high sensitivity, rapidity and selectivity. With the advent of nanotechnology and incorporation of the nanoparticles in the CL system has revolutionized the assays due to their unique optical and mechanical properties. Several CL-based reactions have been developed where these nanoparticle based CL sensors have evolved as excellent prospects for sensing in various analytical applications. This review article addresses the nanoparticles based CL detection system that are recently developed, the mechanisms has been summarized and the role of luminophors have been discussed. This article critically analyzes the optimal conditions for the CL detection along with quantitative assessment of the analytes. We have included the use of semiconductor nanoparticles, metal nanoparticles, graphene based nanostructures, mesoporous nanospheres, layered double hydroxides, clays for CL detection. The scope and application of these nanoscale material based CL system in various branches of science and technology including chemistry, biomedical applications, pharmaceutics, food, environmental and toxicological applications has been critically summarized.
Graphical abstract
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Magnetic solid-phase extraction based on magnetic multiwalled carbon nanotubes for the simultaneous enantiomeric analysis of five β-blockers in the environmental samples by chiral liquid chromatography coupled with tandem mass spectrometry
Publication date: 1 April 2018
Source:Talanta, Volume 180
Author(s): Zhaokun Wang, Xue Zhang, Shenmeng Jiang, Xingjie Guo
In this work, the magnetic multiwalled carbon nanotubes (Mag-MWCNTs) were prepared by self-assembly method and characterized by scanning electron microscopy, X-ray powder diffraction, energy dispersive X-ray and vibrating sample magnetometer. Then, these synthetic Mag-MWCNTs were used as sorbents to extract five β-blockers (atenolol, metoprolol, esmolol, pindolol and arotinolol) by magnetic solid-phase extraction. The target analytes adsorbed on Mag-MWCNTs were eluted and determined on a chiral α-acid glycoprotein column coupled with a triple quadrupole mass spectrometry. Eventually, the proposed method was applied to the analysis of the enantiomeric composition of the studied β-blockers in three environmental samples, including river water, influent wastewater and effluent wastewater. Method detection and quantification limits for all enantiomers were in the range of 0.50–1.45 and 1.63–3.75ng/L, respectively. Satisfactory recovery (82.9–95.6%), good intra-day precision (RSD 0.4–10.4%) and inter-day precision (RSD 2.9–7.4%) were also obtained. With numerous advantages such as simplicity of operation, rapidity and high enrichment factor, the newly developed method has potential to assess the enantioselectivity of chiral drugs in ecotoxicity and biodegradation processes, which is also a new expanded application of Mag-MWCNTs in the environmental analysis.
Graphical abstract
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Mn2+-doped NaYF4:Yb,Er upconversion nanoparticles for detection of uric acid based on the Fenton reaction
Publication date: 1 April 2018
Source:Talanta, Volume 180
Author(s): Yaoyao Zhou, Bo Ling, Hongqi Chen, Lun Wang
A novel fluorescence method for the determination of hydrogen peroxide (H2O2) and uric acid (UA) was developed. The procedure was based on the hydroxyl radicals (·OH), which effectively quenched the fluorescence of the Mn2+-doped NaYF4:Yb,Er upconversion nanoparticles (UCNPs). Based on the property of Mn2+-doped NaYF4:Yb,Er upconversion nanoparticles, the Fenton reaction and enzymatic reaction of uric acid, this method could be used for highly sensitive detection of H2O2 and uric acid. Under optimal conditions, we observed that the fluorescence quenching signal showed good linearity with the H2O2 concentration in the range of 3.00×10-8 M ~ 6.00×10-5 M, and the detection limit of this assay was 1.30×10-8 M. Meanwhile, the linear concentration range for UA was 4.00×10-9 M ~ 1.00×10-5 M, and the lower limit of detection was 1.90×10-9 M. Furthermore, the developed method was successfully used for the determination of UA levels in human serum with satisfactory results.
Graphical abstract
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Local Anesthetic Systemic Toxicity: A Review of Recent Case Reports and Registries
This review summarizes presenting features, management, and outcomes of local anesthetic systemic toxicity (LAST) from published cases and those submitted to online registries capturing use of intravenous lipid emulsion (ILE) therapy. The results of single-center and multicenter registries and epidemiologic studies complement this information. Between March 2014 and November 2016, 47 separate cases of LAST were described in 35 peer-reviewed articles. Local anesthetic systemic toxicity events occurred as a result of penile blocks (23%), local infiltration (17%), and upper/lower extremity, torso, and neuraxial blockade. Twenty-two patients (47%) were treated with ILE, and 2 patients (4.3%) died. During the same time period, 11 cases submitted to lipidrescue.org were treated with ILE and survived. The incidence of LAST reported in registries is 0.03% or 0.27 (95% confidence interval, 0.21–0.35) per 1000 peripheral nerve blocks (denominator of 251,325). Seizure (53% and 61% from case reports and registries, respectively) was the most common presenting feature. Accepted for publication October 9, 2017. Address correspondence to: Marina Gitman, MD, Department of Anesthesiology, College of Medicine, University of Illinois, 1740 W Taylor St, Suite 3200 W, Chicago, IL 60612 (e-mail: gitman@uic.edu). The authors declare no conflict of interest. Copyright © 2018 by American Society of Regional Anesthesia and Pain Medicine.
http://ift.tt/2lZOqpy
http://ift.tt/2lZOqpy
The Prevalence of Cosmetic Facial Plastic Procedures among Facial Plastic Surgeons
Facial plast Surg
DOI: 10.1055/s-0037-1617423
This is the first study to report on the prevalence of cosmetic facial plastic surgery use among facial plastic surgeons. The aim of this study is to determine the frequency with which facial plastic surgeons have cosmetic procedures themselves. A secondary aim is to determine whether trends in usage of cosmetic facial procedures among facial plastic surgeons are similar to that of nonsurgeons. The study design was an anonymous, five-question, Internet survey distributed via email set in a single academic institution. Board-certified members of the American Academy of Facial Plastic and Reconstructive Surgery (AAFPRS) were included in this study. Self-reported history of cosmetic facial plastic surgery or minimally invasive procedures were recorded. The survey also queried participants for demographic data. A total of 216 members of the AAFPRS responded to the questionnaire. Ninety percent of respondents were male (n = 192) and 10.3% were female (n = 22). Thirty-three percent of respondents were aged 31 to 40 years (n = 70), 25% were aged 41 to 50 years (n = 53), 21.4% were aged 51 to 60 years (n = 46), and 20.5% were older than 60 years (n = 44). Thirty-six percent of respondents had a surgical cosmetic facial procedure and 75% has at least one minimally invasive cosmetic facial procedure. Facial plastic surgeons are frequent users of cosmetic facial plastic surgery. This finding may be due to access, knowledge base, values, or attitudes. By better understanding surgeon attitudes toward facial plastic surgery, we can improve communication with patients and delivery of care. This study is a first step in understanding use of facial plastic procedures among facial plastic surgeons.
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Article in Thieme eJournals:
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Ablative Fractional CO2 Laser for Facial Atrophic Acne Scars
Facial plast Surg
DOI: 10.1055/s-0037-1606096
Ablative fractional carbon dioxide laser resurfacing is a well-established treatment for acne scars. However, there are limited consensus and guidelines regarding the procedure, such as its treatment plan, efficacy, and safety. In this study, we performed a systematic review to assess the efficacy and safety of the fractional carbon dioxide laser treatment procedure, and to provide evidence-based recommendations concerning its practical use on atrophic acne scars. A comprehensive search was performed in, EMBASE, Ovid, Web of Science, and Cochrane databases, using the keywords "scar(s)," "acne vulgaris," "carbon dioxide," and "fraction* laser(s)" for the period from January 1987 to December 2016. The initial literature search identified 337 articles. The final selection included 30 studies: 12 retrospective studies and 18 prospective randomized clinical trials. Ablative fractional carbon dioxide laser is an effective therapy for the treatment of acne scars. The treatment session, interval, and parameters should be customized for each patient. Combination therapy should be considered for ice-pick type acne scars. The use of dermocosmetics in pre- and postoperative care may be beneficial to patients.
[...]
Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.
Article in Thieme eJournals:
Table of contents | Abstract | Full text
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High Channel Count Microphone Array Accurately and Precisely Localizes Ultrasonic Signals from Freely-Moving Mice
Source:Journal of Neuroscience Methods
Author(s): Megan R. Warren, Daniel T. Sangiamo, Joshua P. Neunuebel
BackgroundAn integral component in the assessment of vocal behavior in groups of freely interacting animals is the ability to determine which animal is producing each vocal signal. This process is facilitated by using microphone arrays with multiple channels.New Method and Comparison with Existing MethodsHere, we made important refinements to a state-of-the-art microphone array based system used to localize vocal signals produced by freely interacting laboratory mice. Key changes to the system included increasing the number of microphones as well as refining the methodology for localizing and assigning vocal signals to individual mice.ResultsWe systematically demonstrate that the improvements in the methodology for localizing mouse vocal signals led to an increase in the number of signals detected as well as the number of signals accurately assigned to an animal.ConclusionsThese changes facilitated the acquisition of larger and more comprehensive data sets that better represent the vocal activity within an experiment. Furthermore, this system will allow more thorough analyses of the role that vocal signals play in social communication. We expect that such advances will broaden our understanding of social communication deficits in mouse models of neurological disorders.
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The transgenic mouse line Igsf9-eGFP allows targeted stimulation of inferior olive efferents
Source:Journal of Neuroscience Methods, Volume 296
Author(s): Christina Pätz, Simone Brachtendorf, Jens Eilers
BackgroundThe inferior olive (IO) innervates the cerebellum forming synapses in the deep cerebellar nuclei (DCN) and the cerebellar cortex. Beside the well-known exception of synapses on Purkinje neurons, synapses between IO efferents and other neuronal targets have not been studied intensively, mostly due to the technical challenge of unequivocally identifying IO efferents in electrophysiological experiments.New methodWe describe the transgenic mouse line Igsf9-eGFP, which expresses GFP in IO neurons, as a suitable tool for studying IO efferents using live imaging, immunohistochemistry and electrophysiology.ResultsIn the Igsf9-eGFP line, GFP-positive neurons are found in all IO subnuclei. Their efferents show the expected trajectories innervating the DCN and, as climbing fibers (CFs), the cerebellar cortex. In the DCN the dentate nucleus shows the strongest innervation, and, within the cerebellar cortex, CFs show a rostral-to-caudal gradient. GFP-positive CFs undergo a normal postnatal maturation, and evoke normal synaptic responses in Purkinje neurons and DCN neurons.Comparison with existing methodsIO efferents have been labelled via anterograde labelling, viral transfection and in transgenic mouse lines. The latter approach does not require stereotactic injections. However, available mouse lines show only a sparse GFP expression, harbor GFP-positive axons of other cerebellar fibers, or have not been characterized in detail.ConclusionsThe Igsf9-eGFP line is characterized by a moderate density of GFP-positive IO efferents, which can be visually targeted for extracellular stimulation with micrometer precision. The mouse line will allow studying fiber-specific responses in all neurons targeted by the IO.
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The efficacy of pre-operative preparation with intravenous iron and/or erythropoietin in anaemic patients undergoing orthopaedic surgery: An observational study
BACKGROUND Pre-operative anaemia and transfusion are common among patients undergoing elective orthopaedic surgery. Application of 'patient blood management' might be the most effective way to reduce both anaemia and transfusion. Pre-operative administration of iron and/or erythropoietin (EPO) is one of the cornerstones of the first pillar of patient blood management, but in a daily clinical setting, efficacy and long-term safety of this measure have not been analysed thoroughly to date. OBJECTIVE To investigate the influence of pre-operative preparation (PREP) of patients with iron and/or EPO on peri-operative transfusion needs and long-term survival. DESIGN AND METHODS This was a single-centre, retrospective study. After approval of our local ethics committee, data of 5518 patients who received total hip or total knee replacement between 2008 and 2014 were included. Patients receiving iron and/or EPO were included in the PREP group, whereas patients without iron and/or EPO were included in the no preparation group. From the full data set, a bias-reduced subset of 662 patients was obtained by means of propensity score-matching to compare peri-operative red blood cell utilisation and long-term survival of patients between groups. RESULTS Patients in the PREP group needed a lower number of units of red blood cells than patients in the no preparation group (0.2 ± 0.8 vs. 0.5 ± 1.3, P
http://ift.tt/2CWG5uP
http://ift.tt/2CWG5uP
Effect of pressure-controlled inverse ratio ventilation on dead space during robot-assisted laparoscopic radical prostatectomy: A randomised crossover study of three different ventilator modes
BACKGROUND Pressure-controlled inverse inspiratory to expiratory ratio ventilation (PC-IRV) is thought to be beneficial for reducing the dead space volume. OBJECTIVE To investigate the effects of PC-IRV on the components of dead space during robot-assisted laparoscopic radical prostatectomy (RLRP). DESIGN A randomised crossover study of three different ventilator modes. SETTING A single university hospital from September 2014 to April 2015. PATIENTS Twenty consecutive study participants undergoing RLRP. INTERVENTIONS Patients were ventilated sequentially with three different modes in random order for 30 min: volume control ventilation (VCV; inspiratory to expiratory ratio 0.5), pressure control ventilation (PCV; inspiratory to expiratory ratio 0.5) and PC-IRV. Inverse inspiratory to expiratory ratio was adjusted individually by observing the expiratory flow-time wave to prevent the risk of dynamic pulmonary hyperinflation. MAIN OUTCOME MEASURES The primary outcome included physiological dead space (VDphys), airway dead space (VDaw), alveolar dead space (VDalv) and shunt dead space (VDshunt). VDphys was calculated by Enghoff's method. We also analysed respiratory dead space (VDresp) and VDaw using a novel analytical method. Then, VDalv and VDshunt were calculated by VDalv = VDresp − VDaw and VDshunt = VDphys − VDresp, respectively. RESULTS The VDphys/expired tidal volume (VTE) ratio in PC-IRV (29.2 ± 4.7%) was significantly reduced compared with that in VCV (43 ± 8.5%) and in PCV (35.9 ± 3.9%). The VDshunt/VTE in PC-IRV was significantly smaller than that in VCV and PCV. VDaw/VTE in PC-IRV was also significantly smaller than that in VCV but not that in PCV. There was no significant change in VDalv/VTE. CONCLUSION PC-IRV with the inspiratory to expiratory ratio individually adjusted by the expiratory flow-time wave decreased VDphys/VTE in patients undergoing RLRP. TRIAL REGISTRATION University Hospital Medical Information Network in Japan 000014004. Correspondence to Go Hirabayashi, MD, Department of Anaesthesiology, Mizonokuchi Hospital, Teikyo University School of Medicine, 3–8–3 Mizonokuchi, Takatsu-ku, Kawasaki, Kanagawa 213–8507, Japan Tel: +81 44 844 3333; fax: +81 44 844 3390; e-mail: hirabayashi1967@gmail.com Supplemental digital content is available for this article. Direct URL citations appear in the printed text and are provided in the HTML and PDF versions of this article on the journal's Website (http://ift.tt/2ylyqmW). © 2018 European Society of Anaesthesiology
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Vaccination with FasL-/TCL plus MHSP65 induces improved anti-lung cancer immunity in mice
Source:International Immunopharmacology, Volume 55
Author(s): Bohan Dong, Guangli Dai, Yuanyuan Ding, Beiru Wang, Siyuan Zhang
In a previous study, we constructed a MHSP65-TCL anti-lung cancer vaccine with Lewis lung carcinoma TCL plus MHSP65, and illustrated its anti-lung cancer effect through specific and nonspecific anti-tumor immunity. However, TCL contains some immunoinhibit components such as FasL. If this component can be eliminated from TCL, the anti-tumor immunity of MHSP65-TCL constructed with TCL should be improved. In the present study, we knocked down FasL from Lewis lung carcinoma cells and prepared MHSP65-(FasL-/TCL) with this cell line's TCL. After further investigation, MHSP65-(FasL-/TCL) exhibited a better ability to reduce splenocytes apoptosis, promote its activation and secretion of secretingTNF-β, IL-2 compared with MHSP65-(FasL+/TCL). Accordingly, specific and nonspecific antitumor immunity induced by MHSP65-(FasL-/TCL) is stronger than that of MHSP65-(FasL+/TCL). In vivo, MHSP65-(FasL-/TCL) immunization can prolong survival of Lewis lung carcinoma bearing mice. Thus, we report that the anti-lung cancer effect of MHSP65-TCL can be improved by removal of FasL from the TCL. It provides a new route to construct MHSP65-TCL and other antitumor vaccines based on TCL.
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Effects of guluronic acid (G2013) on SHIP1, SOCS1 induction and related molecules in TLR4 signaling pathway
Source:International Immunopharmacology, Volume 55
Author(s): Seyed Shahabeddin Mortazavi-Jahromi, Ali Farazmand, Nasrin Motamed, Shadi Sadat Navabi, Abbas Mirshafiey
ObjectiveThis research aimed to study the anti-inflammatory and immunomodulatory effects of guluronic acid (G2013) on gene expression of TLR4, MyD88, SHIP1, SOCS1, NF-κB, and assessment of the level of IL-1β as a pro-inflammatory cytokine in HEK-Blue hTLR4 cell line.MethodsThe cytotoxicity of G2013 was assessed by the MTT assay. The mRNA expression levels of the mentioned genes were measured by qRT-PCR. IL-1β concentration in culture media was determined using ELISA method.ResultsMTT assay demonstrated that G2013 (before the concentration of 125μg/ml) had no cytotoxic effect on HEK-Blue hTLR4 cells. Our results indicated that the low and high doses of this drug could significantly reduce the gene expression of TLR4 and MyD88, as compared to the control group (p<0.05). Moreover, it was found that the low dose of this drug could significantly increase the gene expression of SHIP1 and SOCS1, as compared to the control group (p<0.05). Furthermore, the study findings revealed that the level of NF-κB gene expression significantly reduced, in both doses of G2013 compared to the control group (p<0.05, p<0.01, respectively). Our data showed that the level of IL-1β in culture media decreased by both doses of this drug in comparison to control group (p<0.05).ConclusionThis study indicates that G2013 is able to induce SHIP1, SOCS1 and reduce TLR4, MyD88, NF-κB at the level of gene expression and decrease IL-1β as a pro-inflammatory cytokine which might be recommended for reduction of inflammatory reactions.
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Zerumbone suppresses the activation of inflammatory mediators in LPS-stimulated U937 macrophages through MyD88-dependent NF-κB/MAPK/PI3K-Akt signaling pathways
Publication date: February 2018
Source:International Immunopharmacology, Volume 55
Author(s): Md. Areeful Haque, Ibrahim Jantan, Hemavathy Harikrishnan
Zerumbone (ZER), isolated mainly from the Zingiber zerumbet (Z. zerumbet) rhizomes was found to be effective against numerous inflammatory and immune disorders, however, the molecular and biochemical mechanisms underlying its anti-inflammatory and immunosuppressive properties have not been well studied. This study was carried out to examine the profound effects of ZER on inflammatory mediated MyD88-dependent NF-κB/MAPK/PI3K-Akt signaling pathways in LPS-stimulated U937 human macrophages. ZER significantly suppressed the up-regulation pro-inflammatory mediators, TNF-α, IL-1β, PGE2, and COX-2 protein in LPS-induced human macrophages. Moreover, ZER significantly downregulated the phosphorylation of NF-κB (p65), IκBα, and IKKα/β as well as restored the degradation of IκBα. ZER correspondingly showed remarkable attenuation of the expression of Akt, JNK, ERK, and p38 MAPKs phosphorylation in a concentration-dependent manner. ZER also diminished the expression of upstream signaling molecules TLR4 and MyD88, which are prerequisite for the NF-κB, MAPK and PI3K-Akt activation. Additionally, quantification of relative gene expression of TNF-α, IL-1β, and COX-2 indicated that, at a higher dose (50μM), ZER significantly downregulated the elevated mRNA transcription levels of the stated pro-inflammatory markers in LPS-stimulated U937 macrophages. The strong suppressive effects of ZER on the activation of inflammatory markers in the macrophages via MyD88-dependent NF-κB/MAPK/PI3K-Akt signaling pathways suggest that ZER can be a preventive and potent therapeutic candidate for the management of various inflammatory-mediated immune disorders.
Graphical abstract
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Cellulose binders for electric double-layer capacitor electrodes: The influence of cellulose quality on electrical properties
Publication date: 5 March 2018
Source:Materials & Design, Volume 141
Author(s): Britta Andres, Christina Dahlström, Nicklas Blomquist, Magnus Norgren, Håkan Olin
Cellulose derivatives are widely used as binders and dispersing agents in different applications. Binders composed of cellulose are an environmentally friendly alternative to oil-based polymer binding agents. Previously, we reported the use of cellulose nanofibers (CNFs) as binders in electrodes for electric double-layer capacitors (EDLCs). In addition to good mechanical stability, we demonstrated that CNFs enhanced the electrical performance of the electrodes. However, cellulose fibers can cover a broad range of length scales, and the quality requirements from an electrode perspective have not been thoroughly investigated. To evaluate the influence of fiber quality on electrode properties, we tested seven samples with different fiber dimensions that are based on the same kraft pulp. To capture the length scale from fibers to nanofibrils, we evaluated the performance of the untreated kraft pulp, refined fibers, microfibrillated cellulose (MFC) and CNFs.Electrodes with kraft pulp or refined fibers showed the lowest electrical resistivity. The specific capacitances of all EDLCs were surprisingly similar, but slightly lower for the EDLC with CNFs. The same electrode sample with CNFs also showed a slightly higher equivalent series resistance (ESR), compared to those of the other EDLCs. Graphite dispersions with MFC showed the best dispersion stability.
Graphical abstract
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Biphasic scaffolds of silk fibroin film affixed to silk fibroin/chitosan sponge based on surgical design for cartilage defect in osteoarthritis
Publication date: 5 March 2018
Source:Materials & Design, Volume 141
Author(s): Khanitta Panjapheree, Suttatip Kamonmattayakul, Jirut Meesane
Osteoarthritis is inflammation that can occur at any joint, and is caused by cartilage degeneration. For severe cases, patients need surgery by substitution with performance tissue engineering scaffolds. Biphasic scaffolds of silk fibroin film affixed to a silk fibroin/chitosan sponge were constructed for osteoarthritis surgery. Silk fibroin film was fabricated before affixation to the sponge of silk fibroin/chitosan at different ratios of silk fibroin to chitosan: 100:0 (SF), 70:30 (SF70), 50:50 (SF50), 30:70 (SF30), and 0:100 (CS). The morphologies of the scaffolds were observed by scanning electron microscopy. Physical functionality as well as stability was evaluated from mechanical properties, and the percentage of swelling, and degradation. Biological functionality was evaluated using a rat mesenchymal stem cell (RMSCs) culture. Cell proliferation was analyzed and the histological structure was observed. SF30 showed suitable morphology, physical stability, and biological functionality to promote RMSC regulation into chondrocytes. This indicated that SF30 shows promise for cartilage regeneration in osteoarthritis surgery.
Graphical abstract
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Numerical methodology to analyze the ice impact threat: Application to composite structures
Publication date: 5 March 2018
Source:Materials & Design, Volume 141
Author(s): J. Pernas-Sánchez, J.A. Artero-Guerrero, J. López-Puente, D. Varas
Impacts on composites produce interlaminar failure (delamination) which is difficult to detect in common maintenance tasks, and affects the structural integrity. Therefore it is critical, for safety, to improve prediction tools in order to perform tolerant damage designs. The numerical modeling of impacts of deformable objects (such as ice) on composite panels is still a challenge. Not only the modeling of the laminate should be appropriate to reproduce its behavior and failures, but also the modeling of the deformable projectile should be capable to induce the corresponding response and damages. In this work a two-step numerical methodology is proposed for the study of ice impact. First, the deformable impactor is analyzed, studying the impact process on a rigid target (a steel plate attached to a load cell). Once the deformable projectile behavior is fully captured, the ice impact on a deformable target (a carbon/epoxy laminate) is studied. The composite material model takes into account intralaminar and interlaminar failure in order to reproduce the laminate behavior. Different ice sphere diameters (30,40 and 50mm) and impact velocities (50−250m/s) are considered in this study. All the results from the numerical simulations have been compared with the experimental results.
Graphical abstract
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Microstructural evolution and compositional homogenization of a low Re-bearing Ni-based single crystal superalloy during through progression of heat treatment
Publication date: 5 March 2018
Source:Materials & Design, Volume 141
Author(s): Xianglin Su, Qingyan Xu, Runnan Wang, Zilin Xu, Shizhong Liu, Baicheng Liu
Microstructural and chemical heterogeneities may exacerbate the high-temperature mechanical properties of single crystal turbine blades. The evolution of microstructure and compositional homogeneity of an as-cast low Re-containing multicomponent DD6 alloy during through progression of heat treatment was detailedly studied. Using optical microscope, field emission gun scanning electron microscope, electron probe microanalysis, differential scanning calorimetry, and complementary thermodynamic calculations, we investigated the time-dependent size and volume fraction variations of γ/γ′ eutectic during specific solution heat treatment steps, the evolution of γ′ precipitates, carbides, and compositional homogeneity, and the thermo-physical changes of as-cast DD6 alloy during through progression of heat treatment. Based on our experimental and theoretical results, the mechanism underlying the microstructure formation and chemical segregation of as-cast DD6 alloy was clarified. The mechanism of microstructural evolution and compositional homogenization, and the diffusion mechanism of elements that occurs between dendritic and interdendritic regions of as-cast DD6 alloy during through progression of heat treatment were elucidated. The correlations between microstructural evolution, compositional homogenization, and thermo-physical changes of as-cast DD6 alloy during through progression of heat treatment were established.
Graphical abstract
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Electrical conductivity of electrospun nanofiber mats of polyamide 6/polyaniline coated with nitrogen-doped carbon nanotubes
Publication date: 5 March 2018
Source:Materials & Design, Volume 141
Author(s): João Paulo Ferreira Santos, Mohammad Arjmand, Guilherme Henrique França Melo, Kambiz Chizari, Rosario Elida Suman Bretas, Uttandaraman Sundararaj
Conductive nanostructures have emerged as the next generation of functional materials for electronic devices. In this work, electrospun nanofiber mats of polyamide 6/polyaniline (PA6/PAni), with high porosity and high surface area, coated with nitrogen-doped carbon nanotubes (N-CNTs) were developed. Employing the chemical vapor deposition technique, N-CNTs were synthesized at various temperatures, e.g., 650, 750, 850, and 950°C. PA6 and PA6/PAni nanofiber mats were produced employing the electrospinning technique. The mats were then dipped in an aqueous suspension containing dispersed and stabilized N-CNTs. The results revealed that the presence of PAni enhanced the adsorption of N-CNTs on the surface of nanofiber mats, thereby improving their electrical conductivity. The highest conductivity was obtained when the mats were coated with N-CNT650. However, the impact of PAni on the conductivity was higher when the mats were coated with N-CNTs synthesized at higher temperatures, i.e., 10−12S/cm for PA6/N-CNT950 and 10−5S/cm for PA6/PAni/N-CNT950, an increase of seven orders of magnitude. It was concluded that the physical features and nitrogen content of N-CNTs had a significant impact on the electrical behavior of the developed mats. Furthermore, it was realized that the synergistic effect between PAni and N-CNT can be employed to build nanostructures with improved conductivity.
Graphical abstract
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Fatigue assessment of multilayer coatings using lock-in thermography
Publication date: 5 March 2018
Source:Materials & Design, Volume 141
Author(s): Andreu Laborda, Andrew Robinson, Shuncai Wang, Yi Zhang, Philippa Reed
Plain bearings experience cyclic loading during operation, which may cause fatigue failure. In the bearings under study a steel backing has a leaded bronze interlayer, covered by a thin (20μm) multilayer coating, which consists of several electroplated layers composed of Sn, Ni and Cu. Commercial performance assessments simulate the conditions of engines in a 'Pass or Fail' test. A new methodology is proposed to assess the fundamental fatigue behaviour for such complex layered bearings. Accelerated fatigue tests on half-shell bearings have been conducted under 3-point bend, whilst the coated side of the bearings are recorded with an infrared camera. Cyclic tests with strain gauges placed on the coating have been performed to evaluate the strains developing during loading. By combining these tests we can rank different coatings. A compliance based failure criterion is also compared with a failure criterion based on early damage revealed by infrared thermography, showing that the latter is far less conservative. Thus, this methodology allows detection of small scale fatigue cracks in the coatings significantly earlier, facilitating assessment and identification of possible mechanisms to explain the differences in fatigue performance between coatings. This provides valuable information to develop new coatings for future bearing designs.
Graphical abstract
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Primary mucinous eccrine carcinoma of the buccal space: A case report and review of the literature
Mucinous eccrine carcinoma is a rare entity that most commonly affects the head and neck. Due to its low frequency of occurrence, review of its etiology, histopathology, and treatment strategies is beneficial to all clinicians who may encounter similar appearing masses.
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Risk factors of sensorineural hearing loss in patients with unilateral safe chronic suppurative otitis media
Chronic suppurative otitis media (CSOM) is the major cause of hearing impairment, especially conductive hearing loss. Few patients also had sensorineural component, the sensorineural hearing loss (SNHL) in CSOM is controversial, especially for safe mucosal type. This study aims to assess the relationship between the frequency of SNHL development in patients with safe mucosal CSOM and its relation to patient's age, sex, duration of disease, size of perforation and different audiological findings.
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Surgical and Endovascular Intervention for Dialysis Access Maturation Failure During and After Arteriovenous Fistula Surgery: Review of the Evidence
Publication date: Available online 5 January 2018
Source:European Journal of Vascular and Endovascular Surgery
Author(s): Jan H.M. Tordoir, Niek Zonnebeld, Magda M. van Loon, Maurizio Gallieni, Markus Hollenbeck
BackgroundMaturation failure is the major obstacle to establishing functional arteriovenous fistulae (AVF) for haemodialysis treatment. Various endovascular and surgical techniques have been advocated to enhance fistula maturation and to increase the number of functional AVFs. This narrative review considers the available evidence of interventional techniques for treatment of AVF non-maturation.ResultsIntra-operative vein dilation and anastomosis modification results in a clinical maturation rate of 74–92% and a 6 month cumulative AVF patency of 79–93%. Percutaneous transluminal angioplasty (PTA) with or without accessory vein obliteration is successful in 43–97% of patients. The long-term primary patency of PTA is rather low and multiple re-interventions are needed to achieve an acceptable cumulative fistula patency. The results of surgical revision exceed the results of endovascular intervention, with a mean primary one year patency of 73% (range 68–78%) compared with 49% (range 28–72%), respectively. The role of accessory vein obliteration remains unclear.ConclusionIntervention for autologous arteriovenous fistula non-maturation is worthwhile and results in an increased number of functional fistulae. The outcome of surgical revision is better than endovascular and might be preferable in certain patient populations.
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Commentary on “A Propensity Matched Comparison for Open and Endovascular Treatment of Post-carotid Endarterectomy Restenosis”
Publication date: Available online 5 January 2018
Source:European Journal of Vascular and Endovascular Surgery
Author(s): A. Ross Naylor
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Spanish Translated Abstracts
Publication date: January 2018
Source:European Journal of Vascular and Endovascular Surgery, Volume 55, Issue 1
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The alveolar bone protective effects of natural products: A systematic review
Source:Archives of Oral Biology, Volume 87
Author(s): Irlan Almeida Freires, Gustavo Machado Santaella, Janaina de Cássia Orlandi Sardi, Pedro Luiz Rosalen
ObjectivesThis systematic review was carried out to identify which naturally-occurring agents and constituents isolated therefrom have effects in preventing bone loss in a ligature-induced periodontitis model.Materials and methodsEight databases were systematically searched for studies of experimental periodontitis. The data were extracted, analyzed, and the treatment outcomes were given scores based on the level of bone destruction as compared to their untreated induced-periodontitis control.Results294 articles were found, of which 15 met the inclusion criteria. The selected studies tested a multi-herbal formulation; extracts (leaves, barks or fruit) of different plant species; and propolis. The most usual dosing protocol consisted of 3-times-a-day, 11-day treatment. The combined gel of Myracrodruon urundeuva (5%) and Lippia sidoides (0.5%) was the most active treatment, reducing 45–65% bone loss in the region of molars as compared to 73.4% of doxycycline (gold-standard). Ginkgo biloba extract (28–56 mg/kg) and propolis (100–200 mg/kg) prevented bone destruction by 50% and 40–44%, respectively. The other tested samples showed intermediate/weak activity in modulating bone resorption.ConclusionsThe gel of M. urundeuva and L. sidoides, and G. biloba and propolis extracts showed strong alveolar bone protective effectiveness in induced-periodontitis in rats. Further translational research should bridge the gap between the rat study outcomes and the clinical efficacy and long-term toxicity of these formulations in humans. The compilation of the vast literature database presented herein may drive further in vivo and clinical studies with the selected efficacious formulations to subsidize their pharmaceutical application.
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The Implications of Non-compliance to Endovascular Aneurysm Repair Surveillance: A Systematic Review and Meta-analysis
Publication date: Available online 5 January 2018
Source:European Journal of Vascular and Endovascular Surgery
Author(s): Matthew Joe Grima, Mourad Boufi, Martin Law, Dan Jackson, Kate Stenson, Benjamin Patterson, Ian Loftus, Matt Thompson, Alan Karthikesalingam, Peter Holt
Objective/backgroundIncreasingly, reports show that compliance rates with endovascular aneurysm repair (EVAR) surveillance are often suboptimal. The aim of this study was to determine the safety implications of non-compliance with surveillance.MethodsThe study was carried out according to the Preferred Items for Reporting of Systematic Reviews and Meta-Analyses (PRISMA) guidelines. An electronic search was undertaken by two independent authors using Embase, MEDLINE, Cochrane, and Web of Science databases from 1990 to July 2017. Only studies that analysed infrarenal EVAR and had a definition of non-compliance described as weeks or months without imaging surveillance were analysed. Meta-analysis was carried out using the random-effects model and restricted maximum likelihood estimation.ResultsThirteen articles (40,730 patients) were eligible for systematic review; of these, seven studies (14,311 patients) were appropriate for comparative meta-analyses of mortality rates. Three studies (8316 patients) were eligible for the comparative meta-analyses of re-intervention rates after EVAR and four studies (12,995 patients) eligible for meta-analysis for abdominal aortic aneurysm related mortality (ARM). The estimated average non-compliance rate was 42.0% (95% confidence interval [CI] 28–56%). Although there is some evidence that non-compliant patients have better survival rates, there was no statistically significant difference in all cause mortality rates (year 1: odds ratio [OR] 5.77, 95% CI 0.74–45.14; year 3: OR 2.28, 95% CI 0.92–5.66; year 5: OR 1.81, 95% CI 0.88–3.74) and ARM (OR 1.47, 95% CI 0.99–2.19) between compliant and non-compliant patients in the first 5 years after EVAR. The re-intervention rate was statistically significantly higher in compliant patients from 3 to 5 years after EVAR (year 1: OR 6.36, 95% CI 0.23–172.73; year 3: OR 3.94, 85% CI 1.46–10.69) year 5: OR 5.34, 95% CI 1.87–15.29).ConclusionThis systematic review and meta-analysis suggest that patients compliant with EVAR surveillance programmes may have an increased re-intervention rate but do not appear to have better survival rates than non-compliant patients.
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Editorial Board
Publication date: January 2018
Source:European Journal of Vascular and Endovascular Surgery, Volume 55, Issue 1
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Selected Abstracts from the January Issue of the Journal of Vascular Surgery
Publication date: January 2018
Source:European Journal of Vascular and Endovascular Surgery, Volume 55, Issue 1
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Forthcoming Events
Publication date: January 2018
Source:European Journal of Vascular and Endovascular Surgery, Volume 55, Issue 1
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One year on: Test your knowledge from the previous year
Publication date: January 2018
Source:European Journal of Vascular and Endovascular Surgery, Volume 55, Issue 1
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Abstracts from Issue 37 of EJVES Short Reports
Publication date: January 2018
Source:European Journal of Vascular and Endovascular Surgery, Volume 55, Issue 1
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Epigenetic mechanisms in odontogenic tumors: A literature review
Publication date: March 2018
Source:Archives of Oral Biology, Volume 87
Author(s): Jorge Sandoval-Basilio, Rogelio González-González, Ronell Bologna-Molina, Mario Isiordia-Espinoza, Gabriela Leija-Montoya, Sofia L. Alcaraz-Estrada, Idanya Serafín-Higuera, Javier González-Ramírez, Nicolás Serafín-Higuera
ObjectiveEpigenetic mechanisms, such as DNA methylation, regulate important biological processes as gene expression and it was suggested that these phenomena play important roles in the carcinogenesis and tumor biology. The aim of this review is to provide the current state of knowledge about epigenetic alterations, focusing mainly on DNA methylation, reported in odontogenic tumors.DesignLiteratures were searched based in the combination of the following keywords: odontogenic tumors, epigenetics, DNA methylation, histone modifications, non-coding RNA, microRNA, DNA methyltransferases. Electronic databases (Medline/PubMed, Scopus and Web of Science) were screened.ResultsThe analysis of epigenetic alterations in different tumors has rapidly increased; however, limited information is available about epigenetic mechanisms involved in the formation of odontogenic tumors. DNA methylation is the most studied epigenetic modification in these tumors and the participation of non-coding RNA's in odontogenic tumors has been recently addressed. Differential expression of DNA methyltransferases, altered DNA methylation patterns and aberrant expression of non-coding RNA's were reported in odontogenic tumors.ConclusionsCurrent studies suggest epigenetics as an emerging mechanism, possibly implicated in etiopathogenesis of odontogenic tumors. Deeper understanding of the epigenetic abnormalities in these tumors could show potential applications as biomarkers or therapeutic possibilities in the future.
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Influence on proliferation and adhesion of human gingival fibroblasts from different titanium surface decontamination treatments: An in vitro study
Publication date: March 2018
Source:Archives of Oral Biology, Volume 87
Author(s): Cao Jie, Tong Wang, Pu Yinfei, Tang Zhihui, Meng Huanxin
ObjectivesTo investigate the effects of different decontamination treatments on microstructure of titanium (Ti) surface as well as proliferation and adhesion of human gingival fibroblasts (HGFs).Material and methodsTi discs with machined (M) and sand blasted, acid etched (SAE) surfaces were treated with five different decontamination treatments: (1) stainless steel curette (SSC), ultrasonic system with (2) straight carbon fiber tip (UCF) or (3) metal tip (UM), (4) rotating Ti brush (RTB), and (5) Er:YAG laser (30 mJ/pulse at 30 Hz). Surface roughness was analyzed under optical interferometry. HGFs were cultured on each disc. Proliferation and adhesive strength were analyzed. qRT-PCR and ELISA were performed to detect the RNA and protein expression of FAK, ITGB1, COL1A1, and FN1 respectively from different Ti surfaces.ResultsSurface roughness increased on M surface. Proliferation, adhesive strength and gene expression were higher on M surface than SAE surface. Decontamination treatments affected surface parameters significantly (P < 0.001), making M surface less smooth while SAE surface became less rough. SSC, UCF, UM and RTB decreased proliferation on M surfaces significantly (P < 0.05). UCF, RTB and laser increased proliferation on SAE surface significantly (P < 0.05). UM decreased adhesive strength on M surface significantly and laser increased adhesive strength on SAE surface significantly (P < 0.05). Gene expression increased with time and was altered by decontamination treatments significantly (P < 0.001).ConclusionsDecontamination treatments influence surface roughness and cell behavior of HGFs. Laser might be an optimal decontamination treatment which has the least negative effect on M surface and the most positive effect on SAE surface.
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Vascular function and cholecalciferol supplementation in CKD: A self-controlled case series
Publication date: Available online 5 January 2018
Source:The Journal of Steroid Biochemistry and Molecular Biology
Author(s): Vivek Kumar, Ashok Kumar Yadav, Manphool Singhal, Vinod Kumar, Anupam Lal, Debasish Banerjee, Krishan Lal Gupta, Vivekanand Jha
Vitamin D deficiency is common and associated with mortality in chronic kidney disease (CKD) patients. Cardiovascular disease (CVD) is the commonest cause of mortality in CKD patients. In a randomized, double blind, placebo controlled trial, we have recently reported favorable effects of vitamin D supplementation on vascular & endothelial function and inflammatory biomarkers in vitamin D deficient patients with non-diabetic stage 3-4 CKD (J Am Soc Nephrol 28: 3100–3108, 2017). Subjects in the placebo group who had still not received vitamin D after completion of the trial received two oral doses 300000 IU of oral cholecalciferol at 8 weeks interval followed by flow mediated dilatation (FMD), pulse wave velocity (PWV), circulating endothelial and inflammatory markers (E-Selectin, vWF, hsCRP and IL-6), 1,25 (OH)2D, iPTH and iFGF-23 assessment at 16 weeks. 31 subjects completed this phase of the study. Last values recorded in the preceding clinical trial were taken as baseline values. Serum 25(OH)D and 1,25(OH)2D increased and FMD significantly improved after cholecalciferol supplementation [mean change in FMD%: 5.8% (95% CI: 4.0-7.5%, p<0.001]. Endothelium independent nitroglycerine mediated dilatation, PWV, iPTH, iFGF-23 and IL-6 also showed favorable changes. The data further cement the findings of beneficial effects of correction of vitamin D deficiency on vascular function.
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