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Παρασκευή 23 Ιουνίου 2017

Di- n -butyl phthalate prompts interruption of spermatogenesis, steroidogenesis, and fertility associated with increased testicular oxidative stress in adult male rats

Abstract

Di-n-butyl phthalate (DBP) is extensively used as plasticizer, and it was ubiquitary released into the environment. The present study was aimed to investigate the effect of DBP on reproductive competence in adult male rats. Adult male rats were received corn oil or DBP injection intraperitoneally (ip) at 100 and 500 mg/kg body weight on 90, 97, 104, and 111 days. Following completion of the experimental period, adult male rats were cohabitated with untreated proestrus female rats for determination of fertilization capacity. Then, adult male rats were sacrificed, and other reproductive endpoints were determined by histopathology and biochemical analysis. The results revealed significant reduction of fertilization potential by decrease mating, fertility indices with increase pre-implantation and post-implantation losses, and resorptions in normal female rat cohabitation with DBP-treated adult male rats. The testes, seminal vesicle tissue somatic indices, epididymal sperm count, motility, viability, and hypoosmotic swelling (HOS) sperm were significantly decreased with increased sperm morphological abnormalities in DBP-treated adult male rats. The disorientation of spermatogenic cells decreased the diameter and epithelial thickness of seminiferous tubule in the testicular histopathology of DBP-exposed rats. Significant reduction of testicular 3β-hydroxysteroid dehydrogenase and 17β-hydroxysteroid dehydrogenase enzyme levels and serum testosterone with increased follicle-stimulating hormone (FSH) and luteinizing hormone (LH) levels were observed in DBP-treated groups. Higher testicular oxidative stress marker (lipid peroxidation product) with lower antioxidant enzymes such as superoxide dismutase, catalase, and glutathione peroxidase levels in DBP-exposed groups was observed. From these results, it can be concluded that DBP increases oxidative stress; it leads to impairment of spermatogenesis, steroidogenesis, and fertility in adult male rats.



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How does vegetation structure influence woodpeckers and secondary cavity nesting birds in African cork oak forest?

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Publication date: August 2017
Source:Acta Oecologica, Volume 83
Author(s): Amalia Segura
The Great Spotted Woodpecker provides important information about the status of a forest in terms of structure and age. As a primary cavity creator, it provides small-medium size cavities for passerines. However, despite its interest as an ecosystem engineer, studies of this species in Africa are scarce. Here, spatially explicit predictive models were used to investigate how forest structural variables are related to both the Great Spotted Woodpecker and secondary cavity nesting birds in Maamora cork oak forest (northwest Morocco). A positive association between Great Spotted Woodpecker and both dead-tree density and large mature trees (>60 cm dbh) was found. This study area, Maamora, has an old-growth forest structure incorporating a broad range of size and condition of live and dead trees, favouring Great Spotted Woodpecker by providing high availability of foraging and excavating sites. Secondary cavity nesting birds, represented by Great Tit, African Blue Tit, and Hoopoe, were predicted by Great Spotted Woodpecker detections. The findings suggest that the conservation of the Maamora cork oak forest could be key to maintaining these hole-nesting birds. However, this forest is threatened by forestry practises and livestock overgrazing and the challenge is therefore to find sustainable management strategies that ensure conservation while allowing its exploitation.



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The effects of biome and spatial scale on the Co-occurrence patterns of a group of Namibian beetles

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Publication date: August 2017
Source:Acta Oecologica, Volume 83
Author(s): Monica Pitzalis, Francesca Montalto, Valentina Amore, Luca Luiselli, Marco A. Bologna
Co-occurrence patterns (studied by C-score, number of checkerboard units, number of species combinations, and V-ratio, and by an empirical Bayes approach developed by Gotelli and Ulrich, 2010) are crucial elements in order to understand assembly rules in ecological communities at both local and spatial scales. In order to explore general assembly rules and the effects of biome and spatial scale on such rules, here we studied a group of beetles (Coleoptera, Meloidae), using Namibia as a case of study. Data were gathered from 186 sampling sites, which allowed collection of 74 different species. We analyzed data at the level of (i) all sampled sites, (ii) all sites stratified by biome (Savannah, Succulent Karoo, Nama Karoo, Desert), and (iii) three randomly selected nested areas with three spatial scales each. Three competing algorithms were used for all analyses: (i) Fixed-Equiprobable, (ii) Fixed-Fixed, and (iii) Fixed-Proportional. In most of the null models we created, co-occurrence indicators revealed a non-random structure in meloid beetle assemblages at the global scale and at the scale of biomes, with species aggregation being much more important than species segregation in determining this non-randomness. At the level of biome, the same non-random organization was uncovered in assemblages from Savannah (where the aggregation pattern was particularly strong) and Succulent Karoo, but not in Desert and Nama Karoo. We conclude that species facilitation and similar niche in endemic species pairs may be particularly important as community drivers in our case of study. This pattern is also consistent with the evidence of a higher species diversity (normalized according to biome surface area) in the two former biomes. Historical patterns were perhaps also important for Succulent Karoo assemblages. Spatial scale had a reduced effect on patterning our data. This is consistent with the general homogeneity of environmental conditions over wide areas in Namibia.



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Evaluation of therapeutic effectiveness of prescribed medications in patients with type 2 diabetes mellitus: Findings from a tertiary care hospital, Lahore, Pakistan

Bareera Rana, Allah Bukhsh, Tahir Mehmood Khan, Ammar Sarwar, Muhammad Ovais Omer, Shazia Qasim Jamshed

Journal of Pharmacy And Bioallied Sciences 2017 9(2):121-125

Aim: The present study was aimed to highlight the current prescribing pattern of oral hypoglycemia in type 2 diabetes mellitus and to evaluate the therapeutic effectiveness of these therapeutic categories in achieving target glycemic control. Methods: This is a prospective, cross-sectional, observational study of 6 months' duration conducted in a tertiary care hospital of Lahore, Pakistan. Results: The current research recruited 145 patients presented in diabetes management center of a tertiary care hospital in Lahore, Pakistan. Mean age of the participants was 50.2 (± 8.5) years. Out of the 145 patients, 63% were females and 37% were males. Most patients were diagnosed to have diabetes within the past 5 years. Diabetes-induced neuropathy was the most common complication (71.7%) among the patients. A large proportion of these patients (70.3%) were also suffering from other comorbidities among which the most common one is hypertension. The average number of prescribed medications was 1.31. Metformin was prescribed to a majority of patients (64%) as monotherapy while 28.96% received combination therapy. Mean glycated hemoglobin (HBA1c) before and after 3 months of treatment was 8.5 (± 2.3) and 8.04 (± 2.1), respectively. Inferential statistics show a strong association between HBA1c and life style modifications and adherence to medication therapy (P = 0.05). However, the correlation between HBA1c and Morisky score and duration of disease was inverse and weak (P = 0.6, 0.4). The t-test values show a small difference between HBA1c values before and after 3 months (t = 0.440 and 0.466, respectively). Conclusion: Optimization of medication regimen and continuous patient education regarding life style modification and adherence to medication therapy are necessitated to bring HBA1c values near to target.

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Statin therapy prescribing for patients with type 2 diabetes mellitus: A review of current evidence and challenges

Mohamed Hassan Elnaem, Mohamad Haniki Nik Mohamed, Hasniza Zaman Huri, Shah M Azarisman, Ramadan Mohamed Elkalmi

Journal of Pharmacy And Bioallied Sciences 2017 9(2):80-87

Use of statin therapy in patients with type 2 diabetes mellitus (T2DM) has been recommended by most clinical guidelines. Cardiovascular disease (CVD) is a leading cause of morbidity and mortality among T2DM patients. It has been proved that statins are effective for primary or secondary CVD prophylaxis. Reports have highlighted the underutilization of statins in clinical practice and the suboptimal adherence to guideline recommendations. This review article points to summarize the current evidence confirming the role of statins in T2DM patients and to provide an overview of factors that may affect statins' prescribing patterns and compliance in clinical practice. Initiatives to enhance statin therapy prescribing should recognize the comprehensive nature of the prescribing process. Attempts to assure proper statin prescribing and utilization can help in achieving better clinical outcomes of statin therapy.

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Pregabalin and uremic pruritus

Khichar Purnaram Shubhakaran

Journal of Pharmacy And Bioallied Sciences 2017 9(2):152-152



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An experimental evaluation of adaptogenic potential of standardized epipremnum aureum leaf extract

Sreemoy Kanti Das, Pinaki Sengupta, Mohd Shahimi Mustapha, Md Moklesur Rahman Sarker

Journal of Pharmacy And Bioallied Sciences 2017 9(2):88-93

Background: Stress is a normal part of everyday life but chronic stress can lead to a variety of stress-related illnesses including hypertension, anxiety, and depression. In the present investigation, standardized leaf extract of Epipremnumaureum was evaluated for its anti-stress potential. Materials and Methods: For the evaluation of anti-stress activity, groups of mice (n = 6) were subjected to forced swim stress and anoxic stress tolerance test in mice 1h after daily treatment of E.aureumextract. Diazepam (5 mg/kg) was taken as a reference standard. Urinary vanillylmandelic acid (VMA) and ascorbic acid were selected as noninvasive biomarkers to assess the anti-stress activity and plasma cortisol, blood ascorbic acid, and weight of adrenal were measured. The 24 h urinary excretion of VMA and ascorbic acid were determined by spectrophotometric methods in all groups under normal and stressed conditions. The hematological parameters (neutrophils, lymphocytes, and eosinophils) were also determined. Results: Administration of E.aureumat doses of 400 and 600 mg/kg wasfound to be effective in inhibiting the stress induced urinary biochemical changes in a dose-dependent manner. Treatment with E. aureum extract prevents the rise in blood ascorbic acid and plasma cortisol. Moreover, the extract prevented the increase in weight of adrenal gland also significantly increased the anoxia stress tolerance time. Dose-dependent significant reduction in white blood cell count was observed in anoxic stress tolerance test as compared to stressed group. Conclusion: Hence, the present study provides scientific support for the positiveadaptogenic effect of E. aureum extract.

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Effect of surface modification on the In vitro protein adsorption and cell cytotoxicity of vinorelbine nanoparticles

Nandhakumar Sathyamoorthy, Dhanaraju Dasaratha Magharla, Sundar Devendaran Vankayalu

Journal of Pharmacy And Bioallied Sciences 2017 9(2):135-143

Context: Nanocarriers possessing long-circulating abilities could take advantage of the pathophysiology of tumor vasculature to achieve spatial placement. To attain such qualities, the drug carriers should possess suitable physicochemical properties such as size and surface hydrophilicity. Aim: The aim of this study was to prepare poly(ε-caprolactone) nanoparticles (NPs) loaded with vinorelbine bitartrate (VB) and to modify its steric properties using polyethylene glycol and poloxamer. Furthermore, the influence of surface modification of NPs on their physicochemical and cell interactive properties was evaluated. Materials and Methods: NPs were prepared by double emulsion solvent extraction–evaporation technique. The prepared NPs were evaluated for their physicochemical properties, in vitro protein adsorption and cell cytotoxicity. Results and Discussion: The NPs were <250 nm with an entrapment efficiency ranging between 40% and 52%. The zeta potential of the NPs varied from −7.52 mV to −1.27 mV depending on the surface modification. The in vitro release studies exhibited a biphasic pattern with an initial burst release followed by controlled release of the drug over 72 h. The protein adsorption studies revealed that the ability to resist protein adsorption was influenced by the concentration of surface-modifying agents and the amount of proteins available for interaction. The surface-modified NPs produced cell cytotoxicity comparable to free VB at higher concentrations owing to sustained release of the drug into the cellular environment. Conclusion: The results emphasize that surface modification of nanocarriers is an essential and effective tool to dodge opsonization and phagocytosis in the physiological milieu.

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Knowledge and awareness of first aid of avulsed tooth among physicians and nurses of hospital emergency department

Sudeep Sreepad Lyer, Antarmayee Panigrahi, Shalini Sharma

Journal of Pharmacy And Bioallied Sciences 2017 9(2):94-98

Introduction: Physicians and nurses of emergency department are often the first line of qualified health-care providers attending the patient in person or parent's query over phone reporting immediately following the dental avulsion. Prompt action by them becomes the decisive factor in survival and prognosis of the tooth. Although a few researchers have evaluated knowledge of emergency room physicians, there is scanty of reports concerning nurses who play a climacteric role. Materials and Methods: A 10-item questionnaire regarding clinical situation apropos dental injury and tooth avulsion, inquiring knowledge of physicians and nurses was administered to 150 each of nursing professionals and physicians of the emergency department. Results: With 100% response rate, the data obtained was subjected to statistical analysis. Results showed lack of knowledge and confidence in both groups. About 66.7% (n = 100) nurses and 74.7% (n = 112) considered reimplantation of avulsed tooth. There was overbalanced confusion regarding storage/transport media and handling of avulsed tooth. Conclusion: The findings from the results suggested a definite inadequacy in knowledge, demanding need for appropriate training for delivering treatment with more predictability and better prognosis.

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Fine tune your review works please!

Shazia Qasim Jamshed

Journal of Pharmacy And Bioallied Sciences 2017 9(2):79-79



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Homology modeling of Leishmania donovani enolase and its molecular interaction with novel inhibitors

Jay Prakash Mahato, Sindhuprava Rana, Maneesh Kumar, Surendra Sarsaiya

Journal of Pharmacy And Bioallied Sciences 2017 9(2):99-105

Introduction: The treatment of Indian tropical disease such as kala-azar is likely to be troublesome to the clinicians as AmpB- and miltefosine-resistant Leishmania donovani has been reported. The rationale behind designed a novel inhibitors of model of L. donovani enolase and performing a binding study with its inhibitors to gain details of the interaction between protein residues and ligand molecules. Methods and Materials: The L. donovani enolase model consists of two typical domains. The N-terminal one contains three-stranded antiparallel β-sheets, followed by six α-helices. The C-terminal domain composes of eleven-stranded mixed α/β-barrel with connectivity. The first α-helix within the C-terminal domain, H7, and the second β-strand, S7, of the barrel domain was arranged in an antiparallel fashion compared to all other α-helices and β-strands. The root-mean-square deviation between predicted model and template is 0.4 Å. The overall conformation of L. donovani enolase model is similar to those of Trypanosoma cruzi enolase and Streptococcus pneumoniae enolase crystal structures. Result: The key amino acid residues within the docking complex model involved in the interaction between model enolase structure and ligand molecule are Lys70, Asn165, Ala168, Asp17, and Asn213. Conclusion: Our theoretical prediction may lead to the establishment of prophylactic and therapeutic approaches for the treatment of kala-azar. This biomedical informatics analysis will help us to combat future kala-azar.

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Validation of a stability-indicating spectrometric method for the determination of sulfacetamide sodium in pure form and ophthalmic preparations

Sofia Ahmed, Noureen Anwar, Muhammad Ali Sheraz, Iqbal Ahmad

Journal of Pharmacy And Bioallied Sciences 2017 9(2):126-134

Introduction: Sulfacetamide sodium is a widely used sulfonamide for ophthalmic infections. Objective: A number of analytical methods have been reported for the analysis of sulfacetamide but they lack the ability to determine both the active drug and its major degradation product, sulfanilamide, simultaneously in a sample. Materials and Methods: In the present study a simple, rapid and economical stability-indicating UV spectrometric method has been validated for the simultaneous assay of sulfacetamide sodium and sulfanilamide in pure form and in ophthalmic preparations. Results: The method has been found to be accurate (recovery 100.03 ±0.589%) and precise (RSD 0.587%) with detectable and quantifiable limits of 1.67×10–6 M (0.04 mg%) and 5.07×10–6 M (0.13 mg%), respectively for the assay of pure sulfacetamide sodium. The method is also found to be accurate and precise to small changes in wavelength, pH and buffer concentration as well as to forced degradation. The study further includes the validation of the method for the assay of pure sulfanilamide in solution, which has been found to be accurate, precise and robust. Conclusion: The results indicate that the proposed two-component spectrometric method is stability-indicating and can be used for the simultaneous assay of both sulfacetamide sodium and sulfanilamide in synthetic mixtures and degraded solutions.

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Analysis of chemical signatures of alkaliphiles using fatty acid methyl ester analysis

Basha Sreenivasulu, Chinthala Paramageetham, Dasari Sreenivasulu, Bukke Suman, Katike Umamahesh, Gundala Prasada Babu

Journal of Pharmacy And Bioallied Sciences 2017 9(2):106-114

Background: Fatty acids occur in nearly all living organisms as the important predominant constituents of lipids. While all fatty acids have essentially the same chemical nature, they are an extremely diverse group of compounds. Materials and Methods: To test the hypothesis, fatty acids of alkaliphiles isolates, Bacillus subtilis SVUNM4, Bacillus licheniformis SVUNM8, Bacillus methylotrohicus SVUNM9, and Paenibacillus dendritiformis SVUNM11, were characterized compared using gas chromatography-mass spectrometry (GC-MS) analysis. Results: The content of investigated ten fatty acids, 1, 2-benzenedicarboxylic acid butyl 2-methylpropyl ester, phthalic acid, isobutyl 2-pentyl ester, dibutyl phthalate, cyclotrisiloxane, hexamethyl, cyclotetrasiloxane, octamethyl, dodecamethyl, heptasiloxane 1,1,3,3,5,5,7,7,9,9,11,11,13,13-etradecamethyl, 7,15-dihydroxydehydroabietic acid, methyl ester, di (trimethylsilyl) ether, hentriacontane, 2-thiopheneacetic acid, undec-2-enyl ester, obviously varied among four species, suggesting each species has its own fatty acid pattern. Conclusions: These findings demonstrated that GC-MS-based fatty acid profiling analysis provides the reliable platform to classify these four species, which is helpful for ensuring their biotechnological interest and novel chemotaxonomic.

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Perspectives about pandemic influenza and its prophylactic measures among final year pharmacy students in Karachi, Pakistan

Najia Rahim, Wajiha Iffat, Sadia Shakeel, Muhammad Iyad Naeem, Faiza Qazi, Mehwish Rizvi, Iqbal Nasiri, Lubna Bashir, Faisal Muhammad Khan, Hina Yaseen, Shazia Jamshed

Journal of Pharmacy And Bioallied Sciences 2017 9(2):144-151

Aims: In flu pandemics, pharmacy students' knowledge, attitudes, and practices are critical to save patients life. The objective of study was to determine the knowledge of and attitude toward the pandemic influenza among the pharmacy students of Karachi, Pakistan. Settings and Designs: The cross-sectional study was conducted from September to December 2014 by adopting a prevalidated questionnaire distributed to senior pharmacy students (final year) in seven private and public sector universities of Karachi. Materials and Methods: A total of 443 pharmacy students responded the survey. Data regarding sociodemographic characteristics of the students, perceptions, level of knowledge and attitudes toward influenza, and prophylactic measures were collected. Statistical Analysis: To compute the correlation between different variables, data were analyzed using Pearson's Chi-square statistic method. P< 0.05 was considered statistical significance for all analysis. Results: Influenza was identified as a viral disease (n = 423; 95.48%) and 282 (71.2%) students correctly identified it as disease affecting humans and pigs. Textbooks reported as most common source of knowledge (n = 282; 64%). Most common symptoms identified were fever (81.94%), sore throat (64.1%), and nonproductive cough (43.34%). The most common preventive measures were covering nose and mouth (268; 60.5%) and wearing protective coverings (254; 57.3%). Only half of the students correctly reported about the route of administration (180; 40.6%) and strains in vaccine (186; 41.98%). The best time for administration of such vaccine was known by only 156 pharmacy students (35.34%). The majority of the students (82.6%) had no idea about the manifestation of influenza pandemic. Knowledge regarding influenza differed according to gender and institutions differing in their affiliation with tertiary care hospitals. Conclusion: It was observed that knowledge about disease progression, transmission, vaccination, and treatment in pharmacy students, especially those who are not getting clinical training in tertiary care hospitals was limited. There is an urgent need to develop awareness programs to increase knowledge of influenza among clinical pharmacists as they are more susceptible to infections and community as a whole.

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Osteoporosis Knowledge among future healthcare practitioners: Findings from a Malaysian public university

Mohamed Hassan Elnaem, Shazia Qasim Jamshed, Ramadan Mohamed Elkalmi, Muhammad Farhan Baharuddin, Muhammad Afif Johari, Nur Ashikin Binti Ab Aziz, Siti Farhanah Binti Ahmad Sabri, Nur Akmal Binti Ismail

Journal of Pharmacy And Bioallied Sciences 2017 9(2):115-120

Background and Objectives: Students in relevant health-care academic programs are the future professionals who should play an active role in increasing community awareness regarding chronic diseases such as osteoporosis. This research aimed to evaluate the knowledge of osteoporosis, one of the growing health-care burdens in Malaysia, among students belong to three different health occupations programs in a Malaysian University. Methods: A cross-sectional study design was conducted to assess the level of knowledge on osteoporosis and to explore the potential association between the study program and osteoporosis-related knowledge among medicine, pharmacy, and allied health sciences students in a Malaysian University. A total of 348 students were approached. The data were collected using validated revised Osteoporosis Knowledge Test questionnaire. Results: The results showed variability in knowledge score between students belonging to different study programs. allied health sciences students have the highest overall total score (median = 20) and nutrition score (median = 16), but for exercise score, both students in allied health sciences and medicine programs shared a similar median score (median = 11.5). More than half of the respondents showed adequate knowledge on osteoporosis. The students from allied health sciences exhibited more knowledge on osteoporosis compared to students in other study programs. Among the Kulliyyah of Pharmacy respondents, the majority did not manage to answer correctly on the whole scale. This was evident by total percentage of 69.91% of the respondents scored below than median score. Conclusion: There is a considerable gap of knowledge regarding osteoporosis among students in various health occupations academic programs. Pharmacy students particularly need focused learning related to exercise and nutrition in preventing osteoporosis during their academic program.

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Erratum: What is the process of obtaining informed consent in a clinical trial? Is it ever justifiable to include someone in a clinical trial without prior informed consent from the individual?



Journal of Pharmacy And Bioallied Sciences 2017 9(2):153-153



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Primary Renal Paragangliomas and Renal Neoplasia Associated with Pheochromocytoma/Paraganglioma: Analysis of von Hippel–Lindau ( VHL ), Succinate Dehydrogenase ( SDHX ) and Transmembrane Protein 127 ( TMEM127 )

Abstract

Alterations of von Hippel-Lindau (VHL), succinate dehydrogenase (SDHX), and TMEM127 have been associated with the development of pheochromocytomas (PCs) and paragangliomas (PGLs) and are also associated with the development of renal neoplasms. This study involved 2 primary renal PGL and 12 cases of PC/PGL with associated renal neoplasia with a mean follow up of 74 months. Germline VHL and SDHX mutation status was obtained from the medical record. Immunohistochemistry for SDHB and mutation analysis for TMEM127 was performed, in addition to analysis of The Cancer Genome Atlas datasets for SDHX and TMEM127 mutated renal cell carcinomas (RCCs). The spectrum of renal neoplasia included clear cell and tubulocystic and papillary RCC, as well as a case of multiple papillary adenomas. Three patients had metastatic PC/PGL and three patients had VHL syndrome. Previously unreported TMEM127 alterations were identified in two patients, both without evidence of VHL syndrome or SDH-deficiency, and were classified as variants of uncertain significance. Primary renal PGL and neoplasia was associated with about 2% of 710 cases of PC/PGL. These were diagnosed concurrently or on average 27 months prior to the PC/PGL, and most were low-grade, low-stage clear cell RCCs. Up to half of patients with PC/PGL and renal neoplasia had VHL syndrome, SDH deficiency, or alterations in TMEM127. One (of three) case of metastatic PC/PGL had SDHB mutation and loss of SDHB by immunohistochemistry. The other two cases had retained SDHB expression.



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Observational Learning During Simulation-Based Training in Arthroscopy: Is It Useful to Novices?

Publication date: Available online 23 June 2017
Source:Journal of Surgical Education
Author(s): Marie-Eve LeBel, John Haverstock, Sayra Cristancho, Lucia van Eimeren, Gavin Buckingham
ObjectiveObserving experts constitutes an important and common learning experience for surgical residents before operating under direct guidance. However, studies suggest that exclusively observing experts may induce suboptimal motor learning, and watching errors from non-experts performing simple motor tasks may generate better performance. We investigated whether observational learning is transferrable to arthroscopy learning using virtual reality (VR) simulation.Setting/DesignIn our surgical simulation laboratory, we compared students learning basic skills on a VR arthroscopy simulator after watching an expert video demonstration of VR arthroscopy tasks or a non-expert video demonstration of the same tasks to a Control group without video demonstration. Ninety students in 3 observing groups (expert, non-expert, and Control) subsequently completed the same procedure on a VR arthroscopy simulator. We hypothesized the non-expert-watching group would outperform the expert-watching group, and both groups to outperform the Control group. We examined performance pretest, posttest, and 1 week later.ParticipantsParticipants were recruited from the final year of medical school and the very early first year of surgical residency training programs (orthopaedic surgery, urology, plastic surgery, and general surgery) at Western University (Ontario, Canada).ResultsAll participants improved their overall performance from pretest to retention (p < 0.001). At initial retention testing, non-expert-watching group outperformed the other groups in camera path length p < 0.05 and time to completion, p < 0.05, and both the expert/non-expert groups surpassed the Control group in camera path length (p < 0.05).ConclusionWe suggest that error-observation may contribute to skills improvement in the non-expert-watching group. Allowing novices to observe techniques/errors of other novices may assist internalization of specific movements/skills required for effective motor performances. This study highlights the potential effect of observational learning on surgical skills acquisition and offers preliminary evidence for peer-based practice (combined non-experts and experts) as a complementary surgical motor skills training strategy.



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18F-FDG PET/CT in a cardiac metastasis in a patient with history of malignant neuroectodermal tumour of the chest wall: Case report and review of the literature

Publication date: Available online 23 June 2017
Source:Revista Española de Medicina Nuclear e Imagen Molecular
Author(s): J.A. Marroquín, A.C. Hernández, J.P. Pilkington, A. Saviatto, M.J. Tabuenca, J.M. Estenoz
The case presented is a 25-year-old male with a malignant neuroectodermal tumour on the left chest wall (Askin tumour), treated with surgery after neoadyuvant chemotherapy and followed by consolidation chemotherapy. After 9 years of disease free survival, the patient developed an acute pulmonary embolism. The echocardiogram, thoracic CT, and cardiac MRI scans revealed a mass in the right atrium. Recurrence of an Askin tumour versus an atrium myxoma was suspected. 18F-FDG PET/CT showed an intense hypermetabolic right atrium mass with extension to the right ventricle highly suggestive of malignancy. The result of the histopathology examination after biopsy and subsequently exeresis of the right atrium mass was consistent with a metastasis of the primary tumour.



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A New Algebraic Method for Quantitative Proton Density Mapping using Multi-Channel Coil Data

Publication date: Available online 23 June 2017
Source:Medical Image Analysis
Author(s): Dietmar Cordes, Zhengshi Yang, Xiaowei Zhuang, Karthik Sreenivasan, Virendra Mishra, Le H. Hua
A difficult problem in quantitative MRI is the accurate determination of the proton density, which is an important quantity in measuring brain tissue organization. Recent progress in estimating proton density in vivo has been based on using the inverse linear relationship between the longitudinal relaxation rate T1 and proton density. In this study, the same type of relationship is being used, however, in a more general framework by constructing 3D basis functions to model the receiver bias field. The novelty of this method is that the basis functions developed are suitable to cover an entire range of inverse linearities between T1 and proton density. The method is applied by parcellating the human brain into small cubes with size 30mm x 30mm x30mm. In each cube the optimal set of basis functions is determined to model the receiver coil sensitivities using multi-channel (32 element) coil data. For validation, we use arbitrary data from a numerical phantom where the data satisfy the conventional MR signal equations. Using added noise of different magnitude and realizations, we show that the proton densities obtained have a bias close to zero and also low noise sensitivity. The obtained root-mean-square-error rate is less than 0.2% for the estimated proton density in a realistic 3D simulation. As an application, the method is used in a small cohort of MS patients, and proton density values for specific brain structures are determined.

Graphical abstract

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