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ObjectivesTo design and validate a feasible simulation to address an identified training gap in the management of intraoperative vitreous loss.MethodsOur simulation consists of a two-part non-toxic mixture that polymerises upon contact within a silicone training eye, to resemble the appearance of vitreous after staining with triamcinolone. This gel can be cut and aspirated with an anterior vitrectomy probe. Experienced consultant ophthalmic surgeons were invited to assess the simulation and anonymously complete validity questionnaires.ResultsSeven senior surgeons participated. Four (57%) strongly agreed and three (43%) agreed that the tissue behaved like vitreous. Six (86%) strongly agreed and one (14%) agreed that instrument handling was realistic. Three (43%) strongly agreed and four (57%) agreed that simulated triamcinolone staining was realistic. Four (57%) strongly agreed and three (43%) agreed that the simulation was visually convincing. Six (86%) strongly agreed and one (14%) agreed that this simulation is useful for training. No participants disagreed with any validity statements.ConclusionsThis novel simulation of anterior vitrectomy has good face and content validity, with unanimous agreement among experienced surgeons of its utility for training in the management of intraoperative vitreous loss.Subject terms: Education, Lens diseases  相似文献   
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In this study, we show that the transmembrane glycoprotein Trop-2 is up-regulated in human prostate cancer (PCa) with extracapsular extension (stages pT3/pT4) as compared to organ-confined (stage pT2) PCa. Consistent with this evidence, Trop-2 expression is found to be increased in metastatic prostate tumors of Transgenic Adenocarcinoma of Mouse Prostate mice and to strongly correlate with α5β1 integrin levels. Using PCa cells, we show that Trop-2 specifically associates with the α5 integrin subunit, as binding to α3 is not observed, and that Trop-2 displaces focal adhesion kinase from focal contacts. In support of the role of Trop-2 as a promoter of PCa metastatic phenotype, we observe high expression of this molecule in exosomes purified from Trop-2-positive PCa cells. These vesicles are then found to promote migration of Trop-2-negative PCa cells on fibronectin, an α5β1 integrin/focal adhesion kinase substrate, thus suggesting that the biological function of Trop-2 may be propagated to recipient cells. In summary, our findings show that Trop-2 promotes an α5β1 integrin-dependent pro-metastatic signaling pathway in PCa cells and that the altered expression of Trop-2 may be utilized for early identification of capsule-invading PCa.  相似文献   
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To perform sputum analysis for verification of pulmonary changes in premenopausal rural Indian women chronically exposed to biomass smoke during cooking.Three consecutive morning sputum samples were collected from 196 women (median age 34 years) cooking with biomass and 149 age-matched control women cooking with cleaner fuel liquefied petroleum gas. Smears made on slides were stained with Papanicolaou and Perl's Prussian blue. Airway oxidative stress was estimated as reactive oxygen species (ROS) generation (by flow cytometry) and superoxide dismutase (SOD) level (by spectrophotometry) in sputum cells. Airway inflammation was measured as sputum levels of interleukin (IL)-6, -8 and tumor necrosis factor- alpha (TNF-α). Particulate matter of diameter less than 10 (PM10) was measured using laser photometer while benzene exposure was monitored by measuring trans, trans-muconic acid (t,t-MA) in urine by HPLC-UV. Compared with control, sputum of biomass users contained more neutrophils, lymphocytes, eosinophils, alveolar macrophages, and showed presence of ciliocytophthoria, Charcot-Leyden crystals, Curschmann's spiral. ROS generation was increased by 2-fold while SOD was depleted by 31% in biomass users. They also had higher sputum levels of IL-6, -8 and TNF-α. Levels of PM10 and t,t-MA were 2.9- and 5.8-times higher in biomass-using women. PM10 and t,t-MA levels were positively associated with cellular changes in the sputum, markers of airway inflammation, and oxidative stress. Cooking with biomass alters sputum cytology, and increases airway inflammation and oxidative stress that might result in further amplification of the tissue damaging cascade in women chronically exposed to biomass smoke.  相似文献   
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Introduction:Spinocerebellar ataxias (SCAs) are hereditary, autosomal dominant progressive neurodegenerative disorders showing clinical and genetic heterogeneity. They are usually manifested clinically in the third to fifth decade of life although there is a wide variability in the age of onset. More than 36 different types of SCAs have been reported so far and about half of them are caused by pathological expansion of the trinucleotide, Cytosine Alanine Guanine (CAG) repeat. The global prevalence of SCA is 0.3-2 per 100,000 population, SCA3 being the commonest variety worldwide, accounting for 20-50 per cent of all cases, though SCA 2 is generally considered as the commonest one in India. However, SCA6 has not been addressed adequately from India though it is common in the eastern Asian countries like, Japan, Korea and Thailand.Objective:The present study was undertaken to identify the prevalence of SCA6 in the city of Kolkata and the eastern part of India.Results:6 of the 83 subjects turned out positive for SCA6, constituting therefore, 13.33% of the patient pool.Discussion:SCA6 is prevalent in the eastern part of India, though not as frequent as the other common varieties.Conclusions:Further community based studies are required in order to understand the magnitude of SCA6 in the eastern part, as well as in other regions of India.  相似文献   
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Management and outcomes of patients with acute coronary syndromes (ACSs) may vary according to patient race and ethnicity. To assess racial differences in presentation and outcome in high-risk North American patients with non-ST-segment elevation (NSTE) ACS, we analyzed baseline racial/ethnic differences and all-cause death or nonfatal myocardial infarction (MI) in 6,077 white, 586 African-American, and 344 Hispanic patients through 30-day, 6-month, and 1-year follow-up. Frequencies of hypertension were 66% for whites, 83% for African-Americans, and 78% for Hispanics (overall p <0.001). Use of angiography was similar across groups. Use of percutaneous coronary intervention (46% for whites, 41% for African-Americans, and 45% for Hispanics, overall p = 0.046) and coronary artery bypass grafting (20% for whites, 16% for African-Americans, and 22% for Hispanics, overall p = 0.044) differed. African-American patients had significantly fewer diseased vessels compared with white patients (p = 0.0001). Thirty-day death or MI was 14% for whites, 10% for African-Americans, and 14% for Hispanics (overall p = 0.034). After adjustment for baseline variables, African-American patients had lower 30-day death or MI compared with white patients (odds ratio 0.73, 95% confidence interval 0.55 to 0.98). There were no differences in 6-month death or MI across racial/ethnic groups. In conclusion, baseline clinical characteristics differed across North American racial/ethnic groups in the SYNERGY trial. African-American patients had significantly better adjusted 30-day outcomes but similar 6-month outcomes compared with white patients.  相似文献   
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We reviewed papers published during the past 18 months (2012-2013) focusing on micro-social contexts of gender and power inequalities as drivers of HIV risks among people who inject drugs (PWID) in intimate heterosexual relationships. Although there has been a proliferation of social and behavioral research on the micro-social contexts of drug injection in heterosexual intimate relationships, there is still a gap in knowledge of these issues, particularly in low- and middle-income countries. Research has identified couple-based approaches for PWID in intimate relationships as an effective HIV prevention strategy to address micro-social contexts driving HIV risks. While HIV incidence has declined in many countries, prevalence remains at troubling levels among PWID and transmission from PWID to their sex partners is increasing in many parts of the world. HIV prevention among drug-using couples must address the importance of the relationship dyad and micro-social contexts.  相似文献   
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Phytoplankton diversity, their abundance based on flow cytometric (FCM) analysis and seasonal nutrient dynamics were investigated from a waste water fed wetland of Eastern India (88° 24.641′E and 22° 33.115′N). The primary objective of the study was to correlate the seasonal fluctuations in phytoplankton abundance to the environmental variables. Total chlorophyll content and FCM based cell counts were used to characterize and quantify the phytoplankton population. Multivariate statistical methods were employed in predicting the possible relationships between biotic and abiotic variables. Distinct seasonal variations characterized by high abundance during the pre-summer period compared to other seasons were detected. The results indicated that environmental factors like water temperature and nutrients, such as various forms of nitrogen and phosphate, influenced the seasonal phytoplankton accumulation. Cluster analysis and non-metric multidimensional scaling helped analyze the seasonal distribution of phytoplankton based on their composition. The dominant genera among the entire phytoplankton community were Scenedesmus spp. of Chlorophyta, followed by Merismopedia spp. of Cyanoprokaryota. Around 3.7 × 105 phytoplankton mL−1 were recorded during the study period. Due to the very high count of individual species in the community, FCM based counting was applied for determination of Species Diversity Index. The entire population was divided into 13 subpopulations based on the cell sorting method and the seasonal abundance in each sub-population was illustrated.

Phytoplankton diversity, their abundance based on flow cytometric (FCM) analysis and seasonal nutrient dynamics were investigated from a waste water fed wetland of Eastern India (88° 24.641′E and 22° 33.115′N).  相似文献   
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