Πέμπτη 3 Νοεμβρίου 2016
Reduced intake of carbohydrate prevents the development of obesity and impaired glucose metabolism in ghrelin O-acyltransferase knockout mice
Source:Peptides
Author(s): Tetsuya Kouno, Nobuteru Akiyama, Kumiko Fujieda, Isamu Nanchi, Tomohiko Okuda, Takanori Iwasaki, Shogo Oka, Hideo Yukioka
A close relationship between acylated-ghrelin and sucrose intake has been reported. However, little has been examined about the physiological action of ghrelin on preference for different types of carbohydrate such as glucose, fructose, and starch. The current study was aimed to investigate the role of acylated-ghrelin in the determinants of the choice of carbohydrates, and pathogenesis of chronic disorders, including obesity and insulin resistance. In a two-bottle-drinking test, ghrelin O-acyltransferase (GOAT) knockout (KO) mice consumed a less amount of glucose and maltodextrin, and almost the same amount of fructose and saccharin solution compared to WT littermates. The increased consumption of glucose and maltodextrin was observed when acylated-ghrelin, but not unacylated-ghrelin, was exogeneously administered in normal C57BL/6J mice, suggesting an association of acylated-ghrelin with glucose-containing carbohydrate intake. When fed a diet rich in maltodextrin, starch and fat for 12 weeks, GOAT KO mice showed less food intake and weight gain, as well as improved glucose tolerance and insulin sensitivity than WT mice. Our data suggests that blockade of GOAT activity may offer a therapeutic option for treatment of obesity and its associated metabolic syndrome by preventing from overconsumption of carbohydrate-rich food.
http://ift.tt/2fkFWEK
Growth hormone-releasing hormone induced transactivation of epidermal growth factor receptor in human triple-negative breast cancer cells
Source:Peptides
Author(s): Eva Vacas, Laura Muñoz-Moreno, Pedro L. Valenzuela, Juan C. Prieto, Andrew V. Schally, María J. Carmena, Ana M. Bajo
Triple-negative breast cancer (TNBC) is a subset of breast cancers which is negative for expression of estrogen and progesterone receptors and human epidermal growth factor receptor-2 (HER2). Chemotherapy is currently the only form of treatment for women with TNBC. Growth hormone-releasing hormone (GHRH) and epidermal growth factor (EGF) are autocrine/paracrine growth factors in breast cancer and a substantial proportion of TNBC expresses receptors for GHRH and EGF. The aim of this study was to evaluate the interrelationship between both these signaling pathways in MDA-MB-468 human TNBC cells. We evaluated by Western blot assays the effect of GHRH on transactivation of EGF receptor (EGFR) as well as the elements implicated. We assessed the effect of GHRH on migration capability of MDA-MB-468 cells as well as the involvement of EGFR in this process by means of wound-healing assays. Our findings demonstrate that in MDA-MB-468 cells the stimulatory activity of GHRH on tyrosine phosphorylation of EGFR is exerted by two different molecular mechanisms: i) through GHRH receptors, GHRH stimulates a ligand-independent activation of EGFR involving at least cAMP/PKA and Src family signaling pathways; ii) GHRH also stimulates a ligand-dependent activation of EGFR implicating an extracellular pathway with an important role for metalloproteinases. The cross-talk between EGFR and GHRHR may be impeded by combining drugs acting upon GHRH receptors and EGFR family members. This combination of GHRH receptors antagonists with inhibitors of EGFR signalling could enhance the efficacy of both types of agents as well as reduce their doses increasing therapeutic benefits in management of human breast cancer.
http://ift.tt/2er11Qg
Immune modules shared by innate lymphoid cells and T cells
In recent years, innate lymphoid cells (ILCs) have emerged as innate correlates to T cells. The similarities between ILCs and T cells indicate that lymphocytes of fundamentally distinct lineages can share core "immune modules" that encompass transcriptional circuitry and effector functions while using nonredundant complementary mechanisms of pattern recognition to enact these functions. We review modules currently recognized to be shared between ILCs and T cells.
http://ift.tt/2ehpvrD
Correction
With regard to the article in the April 2016 issue entitled "Cluster analysis and prediction of treatment outcomes for chronic rhinosinusitis" (J Allergy Clin Immunol 2016;137:1054-62), it has been brought to the Editors' attention that Fig 1 was incorrect as printed. The corrected figure is shown below. The authors note, "We have confirmed that the results in our publication are still accurate, as patients were clustered based upon computer algorithms. These figures were developed after computer clustering as an aid for other researchers who may wish to reproduce our work." The authors regret the error.
http://ift.tt/2fH578v
Advances in allergen immunotherapy in 2015
The year 2015 saw a significant number of advances in allergen immunotherapy (AIT), and several of these are reviewed in this report. Although AIT has been used for more than 100 years, investigations into optimal treatment approaches and mechanisms are ongoing. Among the highlights was a report by an international group of experts who reviewed AIT guidelines from the major specialty societies and addressed potential unmet needs. Herein, advances in the effectiveness, safety, and mechanisms of sublingual and oral immunotherapy are reviewed.
http://ift.tt/2ehrCeZ
Advances in rhinitis and rhinosinusitis in 2015
The last year has seen great progress in the understanding of upper airway disease and in its management. For allergic rhinitis, authors focused on the prediction of and effect on the natural course of disease. New evidence was published for the disease-modifying effect of allergen immunotherapy in terms of avoidance of new sensitizations and prevention of asthma in either randomized or real-life studies. Specifically, for patients with house dust mite allergies, which are often underestimated and difficult to diagnose, the efficacy of SQ house dust mite sublingual immunotherapy tablets has been demonstrated in patients with allergic rhinitis and asthma.
http://ift.tt/2fH9JM2
Innate lymphoid cells in allergic and nonallergic inflammation
In the last decade, the full picture of the role of innate lymphoid cells (ILCs) has been gradually revealed. ILCs are classified into 3 groups based on their transcription factors and cytokine production patterns, which mirror helper T-cell subsets. Unlike T cells and B cells, ILCs do not have antigen receptors. They promptly respond to multiple tissue-derived factors, such as cytokines and alarmins, and produce multiple proinflammatory and immunoregulatory cytokines. It has been reported that ILC-derived cytokines are important for the induction and regulation of inflammation.
http://ift.tt/2ehof81
The Editors' Choice
Obesity is a risk factor for asthma development and aggravation. However, the mechanisms underlying this relationship remain unclear. In this issue, Everaere et al (p 1309) have identified type 2 and 3 innate lymphoid cells (ILCs) as being involved in asthma aggravation by obesity. The authors show that, compared with a low-fat diet, high-fat diet–induced obesity decreased the number of ILCs in mouse adipose tissue while concomitantly increasing it in the lungs in parallel to eosinophil infiltration.
http://ift.tt/2ehiBTr
News Beyond Our Pages
Research continues to support the involvement of innate lymphoid cells (ILCs) in mucosal immunity, and ILCs have been shown to display functional plasticity between group 1 ILCs (ILC1s) and group 3 ILCs (ILC3s). ILC1s, group 2 ILCs (ILC2s), and ILC3s are functionally similar to the subset of helper CD4+ T cells, TH1, TH2, and TH17 cells, respectively, which have also been shown to demonstrate similar plasticity. Silver et al (Nat Immunol 2016;17:626-35; http://ift.tt/2fH7xnN) show that ILC2s also exhibit plasticity when exposed to influenza virus or cigarette smoke through conversion of lung-resident ILC2s into ILC1s characterized by lower expression of the transcription factor GATA-3, which drives TH2 and ILC2 cells.
http://ift.tt/2ehkOyg
News & Notes
The AAAAI Foundation is excited to announce its two events taking place at the 2017 Annual Meeting in Atlanta. An elegant evening of food and entertainment awaits you at the 2017 AAAAI Foundation Benefit and the Fifth Annual AAAAI Foundation 5K Run/Walk invites you to "Light Up the Night." Ticket sales and registration for both events are now open at annualmeeting.aaaai.org.
http://ift.tt/2ehjpYu
Magnetic cobalt ferrite composite as an efficient catalyst for photocatalytic oxidation of carbamazepine
Abstract
A magnetic spinel cobalt ferrite nanoparticle composite (CFO) was prepared via an ultrasonication-assisted co-precipitation method. The morphological structure and surface composition of CFO before and after reaction were investigated by using X-ray diffraction, scanning electron microscopy, transmission electron microscopy, energy dispersive X-ray, and Fourier transform infrared spectroscopy, indicating the consumption of iron oxide during photodegradation. X-ray photoelectron spectroscopy and vibrating sample magnetometry confirm the preparation of the ferrite nanoparticle composite and its magnetic properties. The prepared CFO was then used for the photocatalytic degradation of carbamazepine (CBZ) as an example of pharmaceuticals and personal care products (PPCPs) from aqueous solution. The effects of the nanocomposite dosage, contact time, and solution pH on the photodegradation process were investigated. More than 96% of the CBZ was degraded within 100 min at 0.2 g·L−1 CFO in the presence of UV light. The reactive species for CBZ degradation in the CFO/UV system was identified as hydroxyl radicals by the methanol scavenging method. Combined with the detection of leached iron ions during the process, the CBZ degradation mechanism can be presumed to be heterogeneous and homogeneous photocatalytic degradation in the CFO/UV system. Furthermore, iminostilbene and acridine were detected as intermediate products by GC-MS.
http://ift.tt/2f3RQUa
Cytotoxicity and oxidative stress responses of silica-coated iron oxide nanoparticles in CHSE-214 cells
Abstract
The present study aimed at investigating cytotoxicity and oxidative stress induced by silica-coated iron oxide nanoparticles functionalized with dithiocarbamate (Fe3O4 NPs) in Chinook salmon cells (CHSE-214) derived from Oncorhynchus tshawytscha embryos. A significant reduction in cell viability was evident in response to Fe3O4 NPs as revealed by the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assay after 24 h of exposure. Out of the tested concentrations (10, 20, and 30 μg/ml), the highest concentration has shown significant decrease in the viability of cells after 24 h of exposure. Alterations in the morphology of CHSE-214 cells was also evident at 10 μg/ml concentration of Fe3O4 NPs after 24 h. Fe3O4 NPs elicited a significant dose-dependent reduction in total glutathione content (TGSH), catalase (CAT), glutathione reductase (GR) with a concomitant increase in lipid peroxidation (LPO), and protein carbonyl (PC) at highest concentration (30 μg/ml) after 24 h of exposure. In conclusion, our data demonstrated that Fe3O4 NPs have potential to induce cytotoxicity in CHSE-214 cells, which is likely to be mediated through reactive oxygen species generation and oxidative stress.
http://ift.tt/2feGoIj
Transepidermal water loss in infancy associated with atopic eczema at 2 years: a population-based cohort study
Skin barrier function can be evaluated by measuring transepidermal water loss (TEWL).1,2 High TEWL is found in children with atopic eczema (AE)3 and in infants with a mutation in the gene encoding for profilaggrin,4 a precursor for filaggrin, an important protein for skin barrier function. In a recent study by Kelleher et al5, high TEWL at 2 days and 2 months preceded and predicted AE at 1 year, independent of parental atopy and filaggrin mutation status.
This article is protected by copyright. All rights reserved.
http://ift.tt/2fkDzSj
Transepidermal water loss in infancy associated with atopic eczema at 2 years: a population-based cohort study
Skin barrier function can be evaluated by measuring transepidermal water loss (TEWL).1,2 High TEWL is found in children with atopic eczema (AE)3 and in infants with a mutation in the gene encoding for profilaggrin,4 a precursor for filaggrin, an important protein for skin barrier function. In a recent study by Kelleher et al5, high TEWL at 2 days and 2 months preceded and predicted AE at 1 year, independent of parental atopy and filaggrin mutation status.
This article is protected by copyright. All rights reserved.
http://ift.tt/2fkDzSj
Towards real-time topical detection and characterization of FDG dose infiltration prior to PET imaging
Abstract
Purpose
To dynamically detect and characterize 18F-fluorodeoxyglucose (FDG) dose infiltrations and evaluate their effects on positron emission tomography (PET) standardized uptake values (SUV) at the injection site and in control tissue.
Methods
Investigational gamma scintillation sensors were topically applied to patients with locally advanced breast cancer scheduled to undergo limited whole-body FDG-PET as part of an ongoing clinical study. Relative to the affected breast, sensors were placed on the contralateral injection arm and ipsilateral control arm during the resting uptake phase prior to each patient's PET scan. Time-activity curves (TACs) from the sensors were integrated at varying intervals (0–10, 0–20, 0–30, 0–40, and 30–40 min) post-FDG and the resulting areas under the curve (AUCs) were compared to SUVs obtained from PET.
Results
In cases of infiltration, observed in three sensor recordings (30 %), the injection arm TAC shape varied depending on the extent and severity of infiltration. In two of these cases, TAC characteristics suggested the infiltration was partially resolving prior to image acquisition, although it was still apparent on subsequent PET. Areas under the TAC 0–10 and 0–20 min post-FDG were significantly different in infiltrated versus non-infiltrated cases (Mann–Whitney, p < 0.05). When normalized to control, all TAC integration intervals from the injection arm were significantly correlated with SUVpeak and SUVmax measured over the infiltration site (Spearman ρ ≥ 0.77, p < 0.05). Receiver operating characteristic (ROC) analyses, testing the ability of the first 10 min of post-FDG sensor data to predict infiltration visibility on the ensuing PET, yielded an area under the ROC curve of 0.92.
Conclusions
Topical sensors applied near the injection site provide dynamic information from the time of FDG administration through the uptake period and may be useful in detecting infiltrations regardless of PET image field of view. This dynamic information may also complement the static PET image to better characterize the true extent of infiltrations.
http://ift.tt/2fhBVCj
Performance of cardiac cadmium-zinc-telluride gamma camera imaging in coronary artery disease: a review from the cardiovascular committee of the European Association of Nuclear Medicine (EANM)
Abstract
The trade-off between resolution and count sensitivity dominates the performance of standard gamma cameras and dictates the need for relatively high doses of radioactivity of the used radiopharmaceuticals in order to limit image acquisition duration. The introduction of cadmium-zinc-telluride (CZT)-based cameras may overcome some of the limitations against conventional gamma cameras. CZT cameras used for the evaluation of myocardial perfusion have been shown to have a higher count sensitivity compared to conventional single photon emission computed tomography (SPECT) techniques. CZT image quality is further improved by the development of a dedicated three-dimensional iterative reconstruction algorithm, based on maximum likelihood expectation maximization (MLEM), which corrects for the loss in spatial resolution due to line response function of the collimator. All these innovations significantly reduce imaging time and result in a lower patient's radiation exposure compared with standard SPECT. To guide current and possible future users of the CZT technique for myocardial perfusion imaging, the Cardiovascular Committee of the European Association of Nuclear Medicine, starting from the experience of its members, has decided to examine the current literature regarding procedures and clinical data on CZT cameras. The committee hereby aims 1) to identify the main acquisitions protocols; 2) to evaluate the diagnostic and prognostic value of CZT derived myocardial perfusion, and finally 3) to determine the impact of CZT on radiation exposure.
http://ift.tt/2fhDVdR
Fusion of freehand SPECT and ultrasound: First experience in preoperative localization of sentinel lymph nodes
Abstract
Purpose
Radioguided sentinel lymph node biopsy (SLNB) is the standard of care in breast cancer and melanoma. Additional preoperative Single-photon emission computed tomography (SPECT/CT) for improved anatomical co-registration of the SLNs causes additional radiation exposure and is time-consuming and expensive. The aim of this prospective study was to evaluate a novel approach involving real-time fusion of freehand SPECT (fhSPECT) and ultrasound (US) for anatomical co-registration of SLNs.
Methods
From February 2015 to February 2016, 153 patients were included in this prospective study. All patients underwent lymphoscintigraphy according to practical guidelines and 151 (118 cases of breast cancer, 30 cutaneous malignancies, and three cases of vulvar cancer) of the 153 patients were additionally investigated with fhSPECT-US. FhSPECT connected to a hand-held gamma detector generates three-dimensional images of the radioactivity distribution in the scanned area. For co-registration and real-time fusion of fhSPECT and subsequently performed US, an infrared stereo tracking system was used.
Results
In all patients an SLN was found on lymphoscintigraphy, and the fhSPECT detected corresponding hotspots in all but one patient. In 72 % of patients and 73 % of lymph node basins, real-time anatomical co-registration with US was feasible. The rate of success in achieving good co-registration increased from 60 to 75 % after training by a radiologist specialized in breast imaging. A higher co-registration rate (78 %) was observed in patients with only one SLN than in those with two SLNs (68 %) or three or more SLNs (0 %).
Conclusions
Real-time fusion of fhSPECT and US for preoperative anatomical co-registration of SLNs is feasible. However, before this approach can completely replace preoperative lymphatic imaging, further technical developments are needed.
http://ift.tt/2ffkNNm
18 F-alfatide PET/CT may predict short-term outcome of concurrent chemoradiotherapy in patients with advanced non-small cell lung cancer
Abstract
Purpose
The study aims to investigate the role of 18F-alfatide positron emission tomography/computed tomography (PET/CT) in predicting the short-term outcome of concurrent chemoradiotherapy (CCRT) in patients with advanced non-small cell lung cancer (NSCLC).
Methods
Eighteen patients with advanced NSCLC had undergone 18F-alfatide PET/CT scans before CCRT and PET/CT parameters including maximum and mean standard uptake values (SUVmax/SUVmean), peak standard uptake values (SUVpeak) and tumor volume (TVPET and TVCT) were obtained. The SUVmax of tumor and normal tissues (lung, blood pool and muscle) were measured, and their ratios were denoted as T/NT (T/NTlung, T/NTblood and T/NTmuscle). Statistical methods included the Two-example t test, Wilcoxon rank-sum test, Receiver-operating characteristic (ROC) curve analysis and logistic regression analyses.
Results
We found that SUVmax, SUVpeak, T/NTlung, T/NTblood and T/NTmuscle were higher in non-responders than in responders (P = 0.0024, P = 0.016, P < 0.001, P = 0.003, P = 0.004). According to ROC curve analysis, the thresholds of SUVmax, SUVpeak, T/NTlung, T/NTblood and T/NTmuscle were 5.65, 4.46, 7.11, 5.41, and 11.75, respectively. The five parameters had high sensitivity, specificity and accuracy in distinguishing non-responders and responders. Multivariate logistic regression analyses showed that T/NTlung was an independent predictor of the short-term outcome of CCRT in patients with advanced NSCLC (P = 0.032).
Conclusions
18F-alfatide PET/CT may be useful in predicting the short-term outcome of CCRT in patients with advanced NSCLC.
http://ift.tt/2fhBTKH
SPECT and PET imaging of angiogenesis and arteriogenesis in pre-clinical models of myocardial ischemia and peripheral vascular disease
Abstract
Purpose
The extent of neovascularization determines the clinical outcome of coronary artery disease and other occlusive cardiovascular disorders. Monitoring of neovascularization is therefore highly important. This review article will elaborately discuss preclinical studies aimed at validating new nuclear angiogenesis and arteriogenesis tracers. Additionally, we will briefly address possible obstacles that should be considered when designing an arteriogenesis radiotracer.
Methods
A structured medline search was the base of this review, which gives an overview on different radiopharmaceuticals that have been evaluated in preclinical models.
Results
Neovascularization is a collective term used to indicate different processes such as angiogenesis and arteriogenesis. However, while it is assumed that sensitive detection through nuclear imaging will facilitate translation of successful therapeutic interventions in preclinical models to the bedside, we still lack specific tracers for neovascularization imaging. Most nuclear imaging research to date has focused on angiogenesis, leaving nuclear arteriogenesis imaging largely overlooked.
Conclusion
Although angiogenesis is the process which is best understood, there is no scarcity in theoretical targets for arteriogenesis imaging.
http://ift.tt/2eXFoaX
Dental anxiety in patients with borderline intellectual functioning and patients with intellectual disabilities
Abstract
Background
This study was aimed to investigate the prevalence of dental anxiety in a population of patients with Borderline Intellectual Functioning (BIF) and patients with mild and moderate intellectual disability (ID), and how dental anxiety correlated with their age and gender.
Methods
The sample was made of 700 patients, 287 females and 413 males, 6-to-47 years old, either with borderline intellectual functioning or mild/moderate intellectual disabilities. All patients were administered the Dental Anxiety Scale to assess their level of dental anxiety.
Results
Moderate Anxiety was the most prevalent dental anxiety category for patients with intellectual borderline functioning (15.56 %) and mild intellectual disabilities(18.79 %), while Severe Anxiety was the most prevalent category for patients with moderate intellectual disabilities(21 %). Overall, a statistically significant difference (p < 0.001) between the three groups (BIF, Mild-ID and Moderate-ID) was found. Also, the correlation analysis between participants' age and dental anxiety was statistically significant (p < 0.001); indeed, dental anxiety turned out to decrease with the increasing of the age. Moreover, the analysis between gender and dental anxiety was found to be significant as well (p < 0.001), where higher prevalence of dental anxiety was found in females.
Conclusions
To our knowledge, this is the first study on dental anxiety carried out in the field of intellectual disability. Results show that the higher the level of intellectual disability – and consequently the lower the cognitive functioning – the higher the percentage and the severity of dental anxiety.
http://ift.tt/2eXvQMU
A plea for the development of an universally accepted modular tooth wear evaluation system
Abstract
Background
Tooth wear is considered an increasing oral health problem. Due to its multifactorial nature, recognizing and diagnosing of tooth wear is difficult but nevertheless important. Over the years, a wide variety of evaluation systems has been developed, yet none of them is universally accepted. This has implications for both research and clinical practice.
Discussion
This paper describes an in-depth analysis of four commonly used tooth wear evaluation systems, namely, the Eccles index, the Tooth Wear Index, the Lussi index, and the Basic Erosive Wear Examination. Comparing those systems revealed that despite several similarities, they differ considerably from each other. Notably, all four systems have their specific advantages and disadvantages. However, neither one of them meets all necessary characteristics of a hypothetical, broadly applicable tooth wear evaluation system. In fact, it is not realistic that a single system qualifies for all purposes (for example, diagnosing or monitoring individual patients, performing epidemiological studies, etc.).
Summary
As a potentially feasible solution for this issue, the development of an evaluation system is recommended that consists of multiple, coherent modules, which cover different purposes.
http://ift.tt/2fhGn44
Defining optimal tracer activities in pediatric oncologic whole-body 18 F-FDG-PET/MRI
Abstract
Purpose
To explore the feasibility of reducing administered tracer activities and to assess optimal activities for combined 18F-FDG-PET/MRI in pediatric oncology.
Methods
30 18F-FDG-PET/MRI examinations were performed on 24 patients with known or suspected solid tumors (10 girls, 14 boys, age 12 ± 5.6 [1–18] years; PET scan duration: 4 min per bed position). Low-activity PET images were retrospectively simulated from the originally acquired data sets using randomized undersampling of list mode data. PET data of different simulated administered activities (0.25–2.5 MBq/kg body weight) were reconstructed with or without point spread function (PSF) modeling. Mean and maximum standardized uptake values (SUVmean and SUVmax) as well as SUV variation (SUVvar) were measured in physiologic organs and focal FDG-avid lesions. Detectability of organ structures and of focal 18F-FDG-avid lesions as well as the occurrence of false-positive PET lesions were assessed at different simulated tracer activities.
Results
Subjective image quality steadily declined with decreasing tracer activities. Compared to the originally acquired data sets, mean relative deviations of SUVmean and SUVmax were below 5 % at 18F-FDG activities of 1.5 MBq/kg or higher. Over 95 % of anatomic structures and all pathologic focal lesions were detectable at 1.5 MBq/kg 18F-FDG. Detectability of anatomic structures and focal lesions was significantly improved using PSF. No false-positive focal lesions were observed at tracer activities of 1 MBq/kg 18F-FDG or higher. Administration of 18F-FDG activities of 1.5 MBq/kg is, thus, feasible without obvious diagnostic shortcomings, which is equivalent to a dose reduction of more than 50 % compared to current recommendations.
Conclusion
Significant reduction in administered 18F-FDG tracer activities is feasible in pediatric oncologic PET/MRI. Appropriate activities of 18F-FDG or other tracers for specific clinical questions have to be further established in selected patient populations.
http://ift.tt/2fhDbWn
Role of quantitative myocardial positron emission tomography for risk stratification in patients with hypertrophic cardiomyopathy: a 2016 reappraisal
Abstract
Aims
Myocardial blood flow <1.1 mL/min/g following dipyridamole (Dip-MBF) assessed by positron emission tomography (PET) was identified in 2003 as an important outcome predictor in hypertrophic cardiomyopathy (HCM), based on scans performed in the 90s. However, such extreme Dip-MBF impairment is rarely observed in contemporary cohorts. We, therefore, reassessed the Dip-MBF threshold defining high-risk HCM patients.
Methods
Dip-MBF was measured using 13N-ammonia in 100 HCM consecutive patients, prospectively enrolled and followed for 4.0 ± 2.2 years. Outcome was assessed based on tertiles of Dip-MBF. The study end-point was a combination of cardiovascular death, progression to severe functional limitation, cardioembolic stroke, life-threatening ventricular arrhythmias.
Results
Global Dip-MBF was 1.95 ± 0.85, ranging from 0.7 to 5.9 mL/min/g. Dip-MBF tertile cut-off values were: 0.73 to 1.53 mL/min/g (lowest), 1.54 to 2.13 mL/min/g (middle), and 2.14 to 5.89 mL/min/g (highest). During follow-up, lowest tertile Dip-MBF was associated with sevenfold independent risk of unfavorable outcome compared to the other two tertiles. Dip-MBF 1.35 mL/min/g was identified as the best threshold for outcome prediction. Regional perfusion analysis showed that all cardiac deaths (n = 4) occurred in patients in the lowest tertile of lateral wall Dip-MBF (≤1.72 mL/min/g); septal Dip-MBF was not predictive.
Conclusions
Dip-MBF confirms its role as potent predictor of outcome in HCM. However, the threshold for prediction in a contemporary cohort is higher than that reported in earlier studies. Dip-MBF impairment in the lateral wall, possibly reflecting diffuse disease extending to non-hypertrophic regions, is a sensitive predictor of mortality in HCM.
http://ift.tt/2eXEtr0
Introduction of nuclear medicine research in Japan
Abstract
There were many interesting presentations of unique studies at the Annual Meeting of the Japanese Society of Nuclear Medicine, although there were fewer attendees from Europe than expected. These presentations included research on diseases that are more frequent in Japan and Asia than in Europe, synthesis of original radiopharmaceuticals, and development of imaging devices and methods with novel ideas especially by Japanese manufacturers. In this review, we introduce recent nuclear medicine research conducted in Japan in the five categories of Oncology, Neurology, Cardiology, Radiopharmaceuticals and Technology. It is our hope that this article will encourage the participation of researchers from all over the world, in particular from Europe, in scientific meetings on nuclear medicine held in Japan.
http://ift.tt/2eXD7MN
Impact of aging on cardiac sympathetic innervation measured by 123 I-mIBG imaging in patients with systolic heart failure
Abstract
Purpose
Sympathetic nervous system (SNS) hyperactivity is a salient characteristic of chronic heart failure (HF) and contributes to the progression of the disease. Iodine-123 meta-iodobenzylguanidine (123I-mIBG) imaging has been successfully used to assess cardiac SNS activity in HF patients and to predict prognosis. Importantly, SNS hyperactivity characterizes also physiological ageing, and there is conflicting evidence on cardiac 123I-mIBG uptake in healthy elderly subjects compared to adults. However, little data are available on the impact of ageing on cardiac sympathetic nerve activity assessed by 123I-mIBG scintigraphy, in patients with HF.
Methods and results
We studied 180 HF patients (age = 66.1 ± 10.5 years [yrs]), left ventricular ejection fraction (LVEF = 30.6 ± 6.3 %) undergoing cardiac 123I-mIBG imaging. Early and late heart to mediastinum (H/M) ratios and washout rate were calculated in all patients. Demographic, clinical, and echocardiographic data were also collected. Our study population consisted of 53 patients aged >75 years (age = 77.7 ± 4.0 year), 67 patients aged 62–72 years (age = 67.9 ± 3.2 years) and 60 patients aged ≤61 year (age = 53.9 ± 5.6 years). In elderly patients, both early and late H/M ratios were significantly lower compared to younger patients (p < 0.05). By multivariate analysis, H/M ratios (both early and late) and washout rate were significantly correlated with LVEF and age.
Conclusions
Our data indicate that, in a population of HF patients, there is an independent age-related effect on cardiac SNS innervation assessed by 123I-mIBG imaging. This finding suggests that cardiac 123I-mIBG uptake in patients with HF might be affected by patient age.
http://ift.tt/2e4Qmfi
Development of computational pregnant female and fetus models and assessment of radiation dose from positron-emitting tracers
Abstract
Purpose
Molecular imaging using PET and hybrid (PET/CT and PET/MR) modalities nowadays plays a pivotal role in the clinical setting for diagnosis and staging, treatment response monitoring, and radiation therapy treatment planning of a wide range of oncologic malignancies. The developing embryo/fetus presents a high sensitivity to ionizing radiation. Therefore, estimation of the radiation dose delivered to the embryo/fetus and pregnant patients from PET examinations to assess potential radiation risks is highly praised.
Methods
We constructed eight embryo/fetus models at various gestation periods with 25 identified tissues according to reference data recommended by the ICRP publication 89 representing the anatomy of the developing embryo/fetus. The developed embryo/fetus models were integrated into realistic anthropomorphic computational phantoms of the pregnant female and used for estimating, using Monte Carlo calculations, S-values of common positron-emitting radionuclides, organ absorbed dose, and effective dose of a number of positron-emitting labeled radiotracers.
Results
The absorbed dose is nonuniformly distributed in the fetus. The absorbed dose of the kidney and liver of the 8-week-old fetus are about 47.45 % and 44.76 % higher than the average absorbed dose of the fetal total body for all investigated radiotracers. For 18F-FDG, the fetal effective doses are 2.90E-02, 3.09E-02, 1.79E-02, 1.59E-02, 1.47E-02, 1.40E-02, 1.37E-02, and 1.27E-02 mSv/MBq at the 8th, 10th, 15th, 20th, 25th, 30th, 35th, and 38th weeks of gestation, respectively.
Conclusion
The developed pregnant female/fetus models matching the ICRP reference data can be exploited by dedicated software packages for internal and external dose calculations. The generated S-values will be useful to produce new standardized dose estimates to pregnant patients and embryo/fetus from a variety of positron-emitting labeled radiotracers.
http://ift.tt/2e4Sxzr
Same-day 90 Y radioembolization: implementing a new treatment paradigm
Abstract
Purpose
To assess the feasibility of conducting pretreatment mesenteric angiography, coil embolization, 99mTc macroaggregated albumin (99mTc-MAA) scintigraphy, and 90Y radioembolization treatment in a single, same-day, combined outpatient encounter.
Methods
This was a retrospective study of 78 patients treated during the period 2008 – 2015 who were managed in a single outpatient encounter under the guidance of the Interventional Radiology Department and The Nuclear Medicine Department. Pretreatment planning was performed by reviewing baseline imaging and estimated perfused liver volume bearing the tumor. The region of interest was estimated using 3-D software; this value was used for dosimetry planning. Maximum lung shunting fractions of 10 % for hepatocellular carcinoma and 5 % for liver metastases were assumed. Subsequently, hepatic angiography and 99mTc-MAA scintigraphy were performed followed by 90Y treatment in one outpatient encounter. Total in-room procedure time was recorded.
Results
All patients underwent same-day angiography, 99mTc-MAA scintigraphy and 90Y radioembolization. Of the 78 patients, 16 received multiple segmental treatments to both lobes, 44 received treatment to the right lobe, and 18 received treatment to the left lobe. The median dose was 106 Gy. The median number of 90Y vials needed was two (range one to six). The median in-room time was 160 min (75 – 250 min). The residential status of the patients was as follows, 18 % (14/78) were local residents, 55 % (43/78) traveled from outside the city limits, 18 % (14/78) were from out-of-state, and 9 % (7/78) were resident abroad. Of the 78 patients, 61 (77 %) had hepatocellular carcinoma, and 17 (22 %) had liver metastases. The median lung dose was 3.5 Gy.
Conclusion
This study demonstrated the feasibility of same-day 90Y evaluation and treatment while maintaining the principles of safe and effective 90Y infusion including tumoricidal dosimetry (lobar, segmentectomy), minimization of nontarget flow, and minimization of lung dose. This paradigm translates into expeditious cancer care and significant cost savings.
http://ift.tt/2eCG1Uh
Phase-contrast CT
Source:Academic Radiology
Author(s): Jianbo Jian, Wenxue Zhang, Hao Yang, Xinyan Zhao, Ruijiao Xuan, Dongyue Li, Chunhong Hu
Rationale and ObjectivesCapillarization of sinusoids and change of trabecular thickness are the main histologic features in hepatocellular carcinoma (HCC). Of particular interest are the three-dimensional (3D) visualization and quantitative evaluation of such alterations in the HCC progression. X-ray phase-contrast computed tomography (PCCT) is an emerging imaging method that provides excellent image contrast for soft tissues. This study aimed to explore the potential of in-line PCCT in microstructure imaging of capillarized sinusoids and trabecular structure in human HCC tissues and to quantitatively evaluate the alterations of those fine structures during the development of HCC.Materials and MethodsThis project was designed as an ex vivo experimental study. The study was approved by the institutional review board, and informed consent was obtained from the patients. Eight human resected HCC tissue samples were imaged using in-line PCCT. After histologic processing, PCCT images and histopathologic data were matched. Fine structures in HCC tissues were revealed. Quantitative analyses of capillarized sinusoids (ie, percentage of sinusoidal area [PSA], sinusoidal volume) and trabecular structure (ie, trabecular thickness, surface-area-to-volume ratio [SA/V]) in low-grade (well or moderately differentiated) and high-grade (poorly differentiated) HCC groups were performed.ResultsUsing PCCT, the alterations of capillarized sinusoids and trabecular structure were clearly observed in 3D geometry, which was confirmed by the corresponding histologic sections. The 3D qualitative analyses of sinusoids in the high-grade HCC group were significantly different (P < 0.05) in PSA (7.8 ± 2.5%) and sinusoidal volume (2.9 ± 0.6 × 107 µm3) from those in the low-grade HCC group (PSA, 12.9 ± 2.2%; sinusoidal volume, 2.4 ± 0.3 × 107 µm3). Moreover, the 3D quantitative evaluation of the trabecular structure in the high-grade HCC group showed a significant change (P < 0.05) in the trabecular thickness (87.8 ± 15.6 µm) and SA/V (2.2 ± 1.3 × 103 µm−1) compared to the low-grade HCC group (trabecular thickness, 75.9 ± 7.1 µm; SA/V, 7.5 ± 1.3 × 103 µm−1).ConclusionsThis study provides insights into the 3D alterations of microstructures such as capillarized sinusoids and the trabecular structure at a micrometer level, which might allow for an improved understanding of the development of HCC.
http://ift.tt/2eCH8Dv
Relationships between cardiac innervation/perfusion imbalance and ventricular arrhythmias: impact on invasive electrophysiological parameters and ablation procedures
Abstract
Purpose
To assess the relationship between regional myocardial perfusion and sympathetic innervation parameters at myocardial scintigraphy and intra-cavitary electrophysiological data in patients with ventricular arrhythmias (VA) submitted to invasive electrophysiological study and ablation procedure.
Methods
Sixteen subjects underwent invasive electrophysiological study with electroanatomical mapping (EAM) followed by trans-catheter ablations of VA. Before ablation all patients were studied with a combined evaluation of regional myocardial perfusion and sympathetic innervation by means of tomographic 99mTc-tetrofosmin and 123I- metaiodobenzylguanidine cadmium-zinc-telluride (CZT) scintigraphies, respectively. Off-line spatial co-registration of CZT perfusion and innervation data with the three-dimensional EAM reconstruction was performed in every patient.
Results
CZT revealed the presence of myocardial scar in 55 (20 %) segments. Of the viable myocardial segments, 131 (60 %) presented a preserved adrenergic innervation, while 86 (40 %) showed a significantly depressed innervation (i.e. innervation/perfusion mismatch). On EAM, the invasively measured intra-cavitary voltage was significantly lower in scarred segments than in viable ones (1.7 ± 1.5 mV vs. 4.0 ± 2.2 mV, P < 0.001). Interestingly, among the viable segments, those showing an innervation/perfusion mismatch presented a significantly lower intra-cavitary voltage than those with preserved innervation (1.9 ± 2.5 mV vs. 4.7 ± 2.3 mV, P < 0.001). Intra-cardiac ablation was performed in 63 (23 %) segments. On multivariate analysis, after correction for scar burden, the segments showing an innervation/perfusion mismatch remained the most frequent ablation targets (OR 5.6, 95 % CI 1.5–20.8; P = 0.009).
Conclusions
In patients with VA, intra-cavitary electrical abnormalities frequently originate at the level of viable myocardial segments with depressed sympathetic innervation that frequently represents the ultimate ablation target.
http://ift.tt/2e4QlZ7
Do dysfunctional coping modes mediate the relationship between perceived parenting style and disordered eating behaviours?
Abstract
Background
Preliminary studies suggest that both childhood experiences and coping behaviours may be linked to eating disorder symptoms.
Methods
In this study maladaptive schema coping modes were investigated as mediators in the relationship between perceived negative parenting and disordered eating. A total of 174 adults with eating and/or body image concerns completed questionnaires measuring parenting experiences, schema modes, and disordered eating behaviours.
Results
Perfectionistic Overcontroller, Self-Aggrandiser, Compliant Surrenderer, Detached Protector and Detached Self-Soother coping modes partially explained the variance in the relationships between perceived negative parenting experiences and the behaviours of restricting and compensation (purging and overexercising).
Conclusions
Our findings suggest that Overcompensatory, Avoidant and Surrender coping mechanisms all appear to play a role in the maintenance of eating disorder symptoms, and that there are multiple complex relationships between these and Early Maladaptive Schemas that warrant further investigation.
http://ift.tt/2eqTjFF
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