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51.
Evidence for activation of cellular immune responses in patients with acute hepatitis E. 总被引:1,自引:0,他引:1
Sita Naik Rakesh Aggarwal Subhash R Naik Sunita Dwivedi Sudha Talwar S K Tyagi S D Duhan P Coursaget 《Indian journal of gastroenterology》2002,21(4):149-152
INTRODUCTION: Although acute hepatitis E virus (HEV) infection is known to induce IgM and IgG humoral host immune responses, little is known about occurrence of cellular responses in this infection. We looked for evidence of lymphocyte sensitization to HEV peptides in patients with acute HEV infection. METHODS: peripheral blood lymphocytes were obtained from patients with acute hepatitis E and healthy controls. Proliferation of these lymphocytes in the presence of each of seven peptides with amino acid sequences corresponding to open reading frames 2 and 3 proteins of HEV (3 and 4 peptides, respectively) were studied; no peptide was added to control wells. Proliferative responses with stimulation indices exceeding 3.0 were taken as positive. RESULTS: More patients showed reactivity to two or more HEV peptides than did controls (11/21 vs 5/22, p<0.05). Reactivity to one peptide corresponding to open reading frame 2 of HEV was more frequent in patients than in controls (7/21 vs 1/22, p<0.05). CONCLUSION: Our results show that lymphocytes of patients with acute hepatitis E show sensitization to HEV peptides. This may have significance in understanding the pathogenetic mechanisms of liver injury in this infection. 相似文献
52.
BACKGROUND: An attempt was made to induce aortoarteritis in mice by using various antigens. METHODS AND RESULTS: The Swiss mice were immunized with eight different antigens and were grouped A to G. Group H served as control. The mice were then bled at 1st, 2nd, 4th, 6th and 8th month interval post-immunization for estimating antibody titer. Then the mice were sacrificed and the heart, aorta and kidney were taken out and processed for hematoxylin-eosin staining. There was gradual increase in the antibody titer from 1st month till 4th month within all the experimental groups (A-G), when compared with control group H. The titer started falling sharply from 6th month post-immunization. However, the control group H did not show much variation. When each individual group was compared separately with control group H, the significant statistical value was obtained. Histopathological examination revealed mild inflammation (+) in kidney by 2nd month, moderate inflammation (++) by 6th month, extensive inflammation (+++) by 8th month and alteration in the normal parenchyma of kidney by 8th month. CONCLUSIONS: The histopathological changes brought out through antigens were more pronounced by 8th month following injection of tunica media, tunica adventitia, tunica intima and aorta collagen as compared to that of standard collagen and mouse aorta injections. 相似文献
53.
Sachin Khambadkone Philipp Bonhoeffer 《Catheterization and cardiovascular interventions》2004,62(3):401-408
Percutaneous transcatheter interventions for valve replacement or implantation is one of the most exciting developments in the field of interventional cardiology. Valvular stenosis has been treated by balloon dilatation with early and late results; however, treatment for valvular regurgitation has remained surgical until now. Most new designs have been investigated for implantation of valves in the left or right ventricular outflow tracts. Patients with surgery on the right ventricular outflow tract for congenital heart disease constitute the most common group for reoperations during late follow-up. Surgical pulmonary valve replacement can be performed with low mortality; however, it sets up a substrate for future operations. Also, the risk of cardiopulmonary bypass, infection, bleeding, and ventricular dysfunction remains. A transcatheter technique is likely to have more acceptance and may expand the indications for early intervention for right ventricular outflow tract dysfunction. 相似文献
54.
H S Talwar V S Madiraju S R Murthy R Nath S K Thind 《Metabolism: clinical and experimental》1985,34(2):97-100
Oral feeding of sodium glycolate (50 mg/d/rat for ten days) caused a significant (P less than 0.001) increase in oxalate and taurine excretion and a decrease in liver protein content (P less than 0.05), glycolic acid oxidase levels (P less than 0.01), and glycolic acid dehydrogenase levels (P less than 0.01) as compared to normal untreated rats. Taurine (100 mg/d/rat), when administered along with glycolate, prevented these effects of glycolate as evident from normal urinary excretion of oxalate, liver protein content, glycolic acid oxidase, and glycolic acid dehydrogenase levels in glycolate- plus taurine-fed animals. 相似文献
55.
Pothineni KR Wells BJ Hsiung MC Nanda NC Yelamanchili P Suwanjutah T Prasad AN Hansalia S Lin CC Yin WH Young MS 《Echocardiography (Mount Kisco, N.Y.)》2008,25(8):911-917
There is no gold standard for the measurement of pulmonary regurgitation (PR) severity. Two-dimensional (2D) transthoracic echocardiography is most commonly used to quantify PR severity using color Doppler criteria for aortic regurgitation. However, this method is limited by visualization of only one or two dimensions of the proximal PR jet or vena contracta (VC) precluding accurate assessment of its shape or size. This limitation would be expected to be obviated by three-dimensional (3D) transthoracic echocardiography, which could provide a more accurate quantitative assessment of PR severity. This study evaluated 82 adult patients with PR using 2D and 3D. PR VC area by 3D was obtained by planimetry by positioning the cropping plane exactly parallel to the VC, which was viewed en face by cropping of the 3D data set. Regurgitant volumes were calculated by 2D (assuming a circular VC) and by 3D as a product of the VC and velocity time integral obtained by color Doppler-guided conventional Doppler interrogation of the PR jet.The 3D VC area correlated with 2D jet width (JW)/right ventricular outflow tract (RVOT) width (r = 0.71) and 2D VC area (r = 0.79). 3D JW/RVOT width correlated with 2D JW/RVOT (r = 0.87). 3D regurgitant volumes also correlated with 2D regurgitant volumes (r = 0.76). The 3D VC values of <0.20, 0.20-0.45, 0.46-1.15, and >1.15 cm(2) and regurgitant volumes of <15 ml, 15-50 ml, 51-115 ml, and >115 ml were effective as cutoffs for grades 1, 2, 3, and 4 PR, respectively. In conclusion, quantification of 3D VC area and regurgitant volumes correlate reasonably well with the current 2D methods for measurement of PR. Since 3D visualizes PR VC in three dimensions, it would be expected to provide a more accurate and more quantitative assessment of PR severity as compared to 2D. 相似文献
56.
Objective
We report prevalence and risk factors of metabolic syndrome (MS) in the obese workforce of organized sector in hill city of Himachal Pradesh (HP), India.Methods
The cross-sectional survey study of employees of organized sectors in Shimla city of HP, India, was conducted to collect data of demographics, health behavior, psychosocial factors, anthropometry, blood pressure, and blood chemistry to measure blood glucose and lipid profile in fasting state in 3004 employees using validated tools. Out of 3004 subjects screened, data of 418 subjects with body mass index of ≥30 are analyzed to estimate the prevalence of MS and its risk determinants. The association of demographics, health behavior, and psychosocial factors as the risk determinants were analyzed using multivariable logistic regression modeling.Results
MS was prevalent in 57.6% [95% confidence interval (CI): 52.8%–62.3%]. The central obesity (odds ratio: 10.6, 95% CI: 2.32–48.4) and consumption of frequent or daily alcohol (odds ratio: 1.94, 95% CI: 1.05–3.59),and extra salt (odds ratio: 3.34, 95% CI: 1.09–10.2) were independent risk factors for MS. The consumption of tobacco, vegetables, sugar-sweetened drinks, physical inactivity, and psychosocial factors had no significant association with MS in obese population.Conclusions
MS is highly prevalent among obese employees of organized sector. The consumption of alcohol and extra salt were major behavioral risk factors for MS and therefore have important implications in behavioral modifications for prevention of MS among obese employees in organized sectors. 相似文献57.
Implications of mechanism of bradycardia on response to pacing in patients with unexplained syncope.
Sachin Sud George J Klein Allan C Skanes Lorne J Gula Raymond Yee Andrew D Krahn 《Europace : European pacing, arrhythmias, and cardiac electrophysiology》2007,9(5):312-318
AIM: Asystole >3 s or sinus bradycardia with a ventricular rate <40 in association with complete heart block or sinus node dysfunction are considered to be Class 1 indications for permanent cardiac pacing. Nevertheless, these phenomena may be observed in symptomatic patients with neurocardiogenic syncope, who may not respond to pacing therapy. We hypothesized that the pattern of spontaneous bradycardia in symptomatic patients would distinguish patients with sinus node dysfunction or conduction system disease who would benefit from pacing from patients with neurally-mediated syncope who would derive lesser benefit. METHODS AND RESULTS: Patients with symptomatic spontaneous bradycardia during long-term monitoring for unexplained syncope who underwent pacemaker implantation were classified according to the ISSUE classification system and followed for recurrent syncope. Follow-up included review of medical records, pacemaker clinic visits, and telephone interviews. Loop recorder tracings were reviewed to identify characteristics potentially predicting a favourable response to pacing. Thirty-three patients (21 male; age, 70 +/- 14) were followed for 3.56 +/- 1.71 years. Six patients had a recurrence of syncope during the follow-up. All patients with recurrent syncope despite pacing demonstrated a Type 1A (n = 5) or 1B (n = 1) pattern with gradual onset of bradycardia at baseline, suggesting a neurocardiogenic mechanism. There was no difference in the severity of bradycardia or duration of asystole in baseline loop recorded events in responding and non-responding patients. Multivariate analysis using stepwise logistic regression revealed that the ISSUE classification and the absence of structural heart disease were the only independent predictors of treatment failure of cardiac pacing in patients with spontaneous symptomatic bradycardia. CONCLUSION: Patients with syncope associated with abrupt bradycardia displayed a better response to cardiac pacing therapy than those with gradual onset bradycardia. 相似文献
58.
beta-glucuronidase, cathepsin D, acid and alkaline phosphatases were studied in rhesus monkey endometrium during the menstrual cycle (day -6 to day +10) and pre-implantation stages (day +3 to day +6) of gestation, with day 0 considered as the day of ovulation. Acid hydrolases exhibited low levels in proliferative phase endometria followed by their gradual rise in the secretory phase of the menstrual cycle. Despite no shifts in the levels of serum progesterone and estradiol-17 beta, the pre-implantation period was, however, associated with distinct changes in enzyme profiles characterized by lower absolute levels (P less than 0.05) of acid phosphatase and beta-glucuronidase on days 3 to 6 of gestation, whereas cathepsin D activity declined significantly (P less than 0.05) on days 5 and 6. Alkaline phosphatase showed a characteristic rise during the pre-ovulatory period with a gradual lowering of its level in post-ovulatory phase endometria of a non-fertile cycle; in contrast, during early gestation, alkaline phosphatase activity showed a marked elevation (P less than 0.05) on days 5 and 6 of gestation. The significance of these findings is discussed. 相似文献
59.
The relationship of early and late menarche with adult body dimensions has been studied on a sample of 147 young adult women drawn from an urban Punjabi population of Chandigarh and Ludhiana. The results indicate that girls with early menarche (age 10 to 11) have significantly smaller skeletal dimensions (both longitudinal and transverse) and more subcutaneous fat than those with average or late menarche. The girls with late menarche have on average more height for weight than early maturers. Results indicate that there is a biological determinant of the observed association between menarcheal age and fatness and adult body size. 相似文献
60.
Oral submucous fibrosis (OSMF) is a potentially malignant disorder of the oral cavity. Most of the people affected by OSMF are betel quid chewers. It is characterized by epithelial atrophy and progressive accumulation of collagen fibers in lamina propria and submucosa of the oral mucosa. 7.6% of OSMF cases undergo oral squamous cell carcinoma (OSCC) transformation of which majority display low grade of tumor differentiation. In the present paper, a hypothesis has been proposed to correlate atrophy, turnover rate and surface keratization in OSMF with degree of tumor differentiation in OSCC. A novel hypothesis for epithelial atrophy in OSMF has also been emphasized. 相似文献