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991.
Afreen Ayub Ashish Goyal Anupam Kotwal Aniket Kulkarni Atul Kotwal SM Air Cmde Ajoy Mahen 《Medical Journal Armed Forces India》2013
Background
Compliance and implementation of infection control guidelines have been recognized as efficient means to prevent and control hospital acquired infections.Objectives
To evaluate knowledge and practices about infection control guidelines amongst medical students and to explore their education needs as perceived by them and faculty.Methods
A total of 160 final year students and 100 faculty members of one of the top medical colleges in India were selected by simple random sampling in each group as per sample size of 143 students (alpha 0.05, error 7%, prevalence 60%) and 99 (error 7.5%) faculty. Data collected by pilot-tested, unlinked, anonymous questionnaire.Results
Amongst students, knowledge (77.50%; 95% CI, 70.24–83.72) was mixed with misconceptions. Only 31.25% always followed hand hygiene procedure; 50% recapped needles; disposal of hazardous material into designated containers always was low (sharps 20%, contaminated items 25%). Despite experiencing needle stick injury (6.25%) and splashes (40%), less than 30% reported these as 44% were unaware of reporting procedure. The discord between the perceptions of faculty regarding students and students' own perceptions was clearly evident (all Kappa values less than 0.50). Students and faculty agreed on workshops (58.13% and 58%) and reinforcement by colleagues (51% and 54%) but not on on-job training (51% and 34%) and part of curriculum (48% and 40%) for teaching–learning infection control.Conclusion
Tackling disconnect between students and faculty perceptions and empowering students with knowledge and skills in infection control is important. Approach needs to be researched and formulated as current methods seem to be inadequate. 相似文献992.
Satish Kumar R.M. Gupta Sourav Sen R.S. Sarkar J. Philip Atul Kotwal SM S.H. Sumathi 《Medical Journal Armed Forces India》2013
Background
Human parvovirus B19 is an emerging transfusion transmitted infection. Although parvovirus B19 infection is connected with severe complications in some recipients, donor screening is not yet mandatory. To reduce the risk of contamination, plasma-pool screening and exclusion of highly viraemic donations are recommended. In this study the prevalence of parvovirus B19 in healthy blood donors was detected by ELISA.Methods
A total of 1633 samples were screened for IgM and IgG antibodies against parvovirus B19 by ELISA. The initial 540 samples were screened for both IgM and IgG class antibodies and remaining 1093 samples were screened for only IgM class antibodies by ELISA.Results
Net prevalence of IgM antibodies to human parvovirus B19 in our study was 7.53% and prevalence of IgG antibodies was 27.96%. Dual positivity (IgG and IgM) was 2.40%.Conclusion
The seroprevalence of human parvovirus B19 among blood donor population in our study is high, and poses an adverse transfusion risk especially in high-risk group of patients who have no detectable antibodies to B19. Studies with large sample size are needed to validate these results. 相似文献993.
Barasch A Cunha-Cruz J Curro FA Hujoel P Sung AH Vena D Voinea-Griffin AE;CONDOR Collaborative Group Beadnell S Craig RG DeRouen T Desaranayake A Gilbert A Gilbert GH Goldberg K Hauley R Hashimoto M Holmes J Latzke B Leroux B Lindblad A Richman J Safford M Ship J Thompson VP Williams OD Yin W 《Journal of dental research》2011,90(4):439-444
Case reports and cohort studies have linked bisphosphonate therapy and osteonecrosis of the jaws (ONJ), but neither causality nor specific risks for lesion development have been clearly established. We conducted a 1:3 case-control study with three dental Practice-based Research Networks, using dentist questionnaires and patient interviews for collection of data on bisphosphonate therapy, demographics, co-morbidities, and dental and medical treatments. Multivariable logistic regression analyses tested associations between bisphosphonate use and other risk factors with ONJ. We enrolled 191 ONJ cases and 573 controls in 119 dental practices. Bisphosphonate use was strongly associated with ONJ (odds ratios [OR] 299.5 {95%CI 70.0-1282.7} for intravenous [IV] use and OR = 12.2 {4.3-35.0} for oral use). Risk markers included local suppuration (OR = 7.8 {1.8-34.1}), dental extraction (OR = 7.6 {2.4-24.7}), and radiation therapy (OR = 24.1 {4.9-118.4}). When cancer patients (n = 143) were excluded, bisphosphonate use (OR = 7.2 {2.1-24.7}), suppuration (OR = 11.9 {2.0-69.5}), and extractions (OR = 6.6 {1.6-26.6}) remained associated with ONJ. Higher risk of ONJ began within 2 years of bisphosphonate initiation and increased four-fold after 2 years. Both IV and oral bisphosphonate use were strongly associated with ONJ. Duration of treatment > 2 years; suppuration and dental extractions were independent risk factors for ONJ. 相似文献
994.
995.
Burger CD Foreman AJ Miller DP Safford RE McGoon MD Badesch DB 《Mayo Clinic proceedings. Mayo Clinic》2011,86(2):105-112
OBJECTIVE: To investigate the correlation between body mass index (BMI) and pulmonary artery systolic pressure in a large population of patients with pulmonary arterial hypertension (PAH).PATIENTS AND METHODS: The BMI of patients with group 1 PAH enrolled in the Registry to Evaluate Early and Long-term PAH Disease Management (REVEAL) was compared with that of age- and sex-matched controls in the National Health and Nutrition Examination Survey (NHANES) to clarify whether obesity is linked with PAH. The diagnosis of PAH was defined in REVEAL by right-sided heart catheterization. Differences in BMI and the percentage of patients considered obese (BMI ≥30) and underweight (BMI <18.5) in various subgroups of patients enrolled in REVEAL from March 30, 2006, through September 11, 2007, were determined.RESULTS: Mean BMI was no different for patients with PAH (n=2141) than for the NHANES normal comparison group; however, the proportion of obese and underweight patients was increased in patients with PAH. Subgroup analysis demonstrated that subgroups with idiopathic PAH and those with PAH associated with drugs and toxins had both higher BMI and percentage of obese patients, whereas 3 other subgroups (those with PAH associated with congenital heart disease, connective tissue disease, and human immunodeficiency virus) had lower mean BMI.CONCLUSION: Mean BMI of the REVEAL patients was the same as that of the NHANES normal comparison group; however, there were higher percentages of obese and underweight patients in REVEAL. This discrepancy can be explained by the balancing effect of more overweight and underweight patients in different PAH subgroups. The reason for the increased frequency of obesity in idiopathic PAH is unknown, and additional study is needed.Trial Registration: clinicaltrials.gov Identifier: APAH = associated PAH; BMI = body mass index; CHD-APAH = congenital heart disease–APAH; CTD-APAH = connective tissue disease–APAH; FPAH = familial PAH; HIV-APAH = human immunodeficiency virus infection–APAH; IPAH = idiopathic PAH; LVEDP = left ventricular end-diastolic pressure; NHANES = National Health and Nutrition Examination Survey; PAH = pulmonary arterial hypertension; PAP = pulmonary artery pressure; PCWP = pulmonary capillary wedge pressure; PH = pulmonary hypertension; REVEAL = Registry to Evaluate Early and Long-term PAH Disease Management; RHC = right-sided heart catheterizationData from the National Health and Nutrition Examination Survey (NHANES) have demonstrated that 35% of US adults are classified as obese (body mass index [BMI], calculated as the weight in kilograms divided by the height in meters squared, ≥30). NCT003702141,2 In addition, up to 46% of patients with pulmonary arterial hypertension (PAH) have no clear cause for the disease (ie, idiopathic PAH [IPAH]).3 Although obesity is epidemic in the United States,1,2 comprehensive reviews have listed obesity as an unlikely risk factor for PAH.4 However, there are no confirmed reports of a direct correlation of obesity with clinically significant PAH. Although a correlation between BMI and pulmonary artery systolic pressure has been identified in otherwise echocardiographically normal persons (Spearman rank correlation, 0.19; P<.01; N=3790),5 a retrospective review of 401 patients in the pulmonary hypertension (PH) database of Mayo Clinic in Florida found no correlation between BMI and diagnosis of PH when these patients were compared with controls (n=578).6PAH is characterized by mean pulmonary artery pressure (PAP) of 25 mm Hg or greater and pulmonary capillary wedge pressure (PCWP) of 15 mm Hg or less.3,7 Group 1 PH comprises 5 categories: IPAH, familial PAH (FPAH; now referred to as heritable PAH), associated PAH (APAH; including PAH associated with connective tissue disease [CTD-APAH], drugs and toxins-PAH), congenital heart disease [CHD-APAH], human immunodeficiency virus infection [HIV-APAH], portal hypertension, schistosomiasis, and chronic hemolytic anemia), and persistent PH of the newborn.8The Registry to Evaluate Early and Long-term PAH Disease Management (REVEAL) represents a unique opportunity to examine the potential relationship between obesity and PAH. REVEAL is a prospective study initiated to characterize the demographics, clinical course, hemodynamic features, and disease management of about 3500 US patients with group 1 PH.3,9 This large database of patients with PAH permits a robust analysis of BMI and the percentage of overweight and underweight patients with PAH. REVEAL also provides an opportunity to identify potential associated risk factors in patients with IPAH, which, if confirmed, may generate hypothesis-based investigations to help determine causal links. In the current study, we compared patients in the REVEAL database with age- and sex-matched controls from NHANES to determine whether a relationship exists between BMI and the presence of PAH. 相似文献
996.
Background
Hepatitis C virus (HCV) infection is common in renal transplant (RT) patients. Some of these patients remain anti-HCV negative despite presence of infection and these are identified by a positive HCV-ribonucleic acid (RNA) test.Methods
We studied 404 RT patients for prevalence of HCV-RNA positivity in anti-HCV negative patients. Serum was tested for presence of anti-HCV antibodies using a third generation HCV micro-ELISA (enzyme-linked immunosorbent assay) test, which utilises a combination of HCV structural and nonstructural antigens. The RNA was extracted from patient serum for HCV viral quantification using Quiagen Ql Amp Viral RNA mini extraction kit. The HCV-RNA viral load was performed on Corbet Rotor Gene 3000 thermocycler using Taqman principle.Results
About 308 patients were anti-HCV negative and 96 were anti-HCV positive, resulting in prevalence of overt HCV infection of 23.7%. A total of 130 anti-HCV negative patients tested positive for HCV-RNA making a prevalence of occult HCV infection of 42.2%. There was no significant difference in the rate of overt or occult HCV infection between males and females. Patients with HCV infection (whether overt or occult) had received more number of dialysis sessions (62.5 vs 32.2) and blood transfusions (2.78 vs 1.99) when compared to those without HCV infection (P=0.001). The mean duration on dialysis was also longer (8.15 months vs 4.53 months) in patients with HCV infection (P= 0.0001).Conclusion
A direct test for HCV viraemia is important to accurately determine the epidemiology of HCV infection in RT patients who remain anti-HCV negative despite harbouring active HCV infection. 相似文献997.
998.
Background and purpose:
Diadenosine polyphosphates are normally present in cells at low levels, but significant increases in concentrations can occur during cellular stress. The aim of this study was to investigate the effects of diadenosine pentaphosphate (Ap5A) and an oxidized analogue, oAp5A on the gating of sheep cardiac ryanodine receptors (RyR2).Experimental approach:
RyR2 channel function was monitored after incorporation into planar bilayers under voltage-clamp conditions.Key results:
With10 µmol·L−1 cytosolic Ca2+, a significant ‘hump’ or plateau at the base of the dose–response relationship to Ap5A was revealed. Open probability (Po) was significantly increased to a plateau of approximately 0.2 in the concentration range 100 pmol·L−1–10 µmol·L−1. High Po values were observed at >10 µmol·L−1 Ap5A, and Po values close to 1 could be achieved. Nanomolar levels of ATP and adenosine also revealed a hump at the base of the dose–response relationships, although GTP did not activate at any concentration, indicating a common, high-affinity binding site on RyR2 for adenine-based compounds. The oxidized analogue, oAp5A, did not significantly activate RyR2 via the high-affinity binding site; however, it could fully open the channel with an EC50 of 16 µmol·L−1 (Ap5A EC50 = 140 µmol·L−1). Perfusion experiments suggest that oAp5A and Ap5A dissociate slowly from their binding sites on RyR2.Conclusions and implications:
The ability of Ap5A compounds to increase Po even in the presence of ATP and their slow dissociation from the channel may enable these compounds to act as physiological regulators of RyR2, particularly under conditions of cellular stress. 相似文献999.
1000.
L Jolly JE March PA Kemp T Bennett SM Gardiner 《British journal of pharmacology》2009,157(8):1502-1513