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41.
Cytotaxonomical investigations on 11 species from the Western Himalayas show that 8 are diploid and the remaining tetraploid. The numbers for three species are new.P. prescottianum (2x) andP. thomsoni (4x), andP. stimulans (2x) andP. acanthophyllum (4x) are closely related but distinct species pairs.  相似文献   
42.
Aim The study was carried to determine the association of angiotensin converting enzyme (ACE) insertion/deletion (I/D) polymorphism with the risk of hypertrophic cardiomyopathy (HCM), dilated cardiomyopathy (DCM), and restrictive cardiomyopathy (RCM). Methods and results A total of 174 patients diagnosed with cardiomyopathy (118 with HCM, 51 with DCM, and 5 with RCM) and 164 ethnically, age- and gender-matched controls were included in the study. ACE I/D genotyping was performed by PCR. In total, 25.86% of the patients were in New York Heart Association (NYHA) class III and IV at presentation. A total of 67.24% patients had dyspnea, 56.89% had angina pectoris, and 25.28% of the patients had at least one event of syncope. Frequency of occurrence of the disease was more in male patients compared to female patients (P < 0.05). After adjustment for age, sex, body mass index (BMI), and smoking habit, the prevalence of ACE DD genotype, and ACE ‘D’ allele was significantly higher in patients as compared to controls and was associated with increased risk (DD: OR 2.11, 95% CI 1.27–3.52, P < 0.05; ‘D’: OR 1.91, 95% CI 1.08–3.35, P < 0.05). The mean septal thickness was higher for DD and ID genotypes (20.40 ± 3.73 mm and 21.82 ± 5.35 mm, respectively) when compared with II genotype (18.63 ± 6.69 mm) in HCM patients, however, the differences were not significant statistically (P > 0.05). The DCM patients with ID genotype showed significantly decreased left ventricular ejection fraction (LVEF) at enrolment (26.50 ± 8.04%) (P = 0.04). Conclusion Our results suggest that D allele of ACE I/D polymorphism significantly influences the HCM and DCM phenotypes.  相似文献   
43.
Objective To evaluate the status of oxidative stress in patients with different primary glomerular diseases (PGD) which have differential predisposition to renal failure. Methods Seventy-three patients with PGD and 50 controls were enrolled in the study. They were sub-grouped into non-proliferative glomerulonephritis (NPGN) and proliferative glomerulonephritis (PGN). Levels of serum malondialdehyde (MDA), reactive nitrogen intermediates (RNI), plasma total homocysteine (tHcy), urine 8-isoprostane (8-IP), RBC thiols, glutathione-S-transferase (GST) and serum superoxide dismutase (SOD) were measured spectrophotometrically. Results PGD patients showed a significant increase in MDA, RNI, tHcy, 8-IP levels (P < 0.05) and decreased SOD, total thiols and protein bound thiol levels as compared to controls (P < 0.05). Significantly higher levels of tHcy, MDA and 8-IP (P < 0.05) and lower SOD enzyme activity (P < 0.05) were observed in PGN group as compared to NPGN and control groups. These changes remained significant even after adjustment was made for creatinine. Conclusions Oxidative stress in PGN is significantly higher than NPGN, indicating higher oxidative stress in these patients, independent of degree of renal dysfunction.  相似文献   
44.
To determine whether liquid ventilation (LV) causes less cell injury and improves lung function compared with conventional gas ventilation (GV), we analyzed pulmonary physiological profiles, lung histology, and cell death in 110- and 120-day preterm lambs, which were randomized to receive either ventilation modality on FI(O(2)) = 1. LV lungs were well expanded with adequate pulmonary function, whereas GV animals exhibited marked atelectasis, poor pulmonary function, and increased mortality. Both ventilatory strategies induced marked lung cell apoptosis, but with distinct patterns of distribution. Although GV induced apoptosis of epithelium primarily in the lining and within the lumina of bronchioles, LV induced significant apoptosis much more homogeneously throughout lung parenchyma including alveoli and interstitial spaces. These studies suggest that although both forms of ventilation cause regional apoptosis, LV more effectively delivers oxygen and recruits the lung more homogeneously than GV.  相似文献   
45.
Mucus-bacterial interactions in the gastrointestinal tract and their impact on subsequent enteric infections are poorly delineated. In the present study, we have examined the binding ofSalmonella typhimurium to rat intestinal mucus and characterized a mucus protein (Mucus-Rs) which specifically binds to S. typhimurium. Both virulent (1402/84), and avirulent (SF 1835) S. typhimurium were observed to bind to crude mucus, however, the virulent strain showed 6 fold more binding as compared to avirulent strain. Fractionation of crude mucus on sepharose CL-6B resolved it into three major peaks. Maximal bacterial binding was observed with a high mol. wt. glycoprotein corresponding to neutral mucin. SDS-PAGE of purified protein (termed Mucus-Rs) under non reducing conditions showed it to be a homogenous glycoprotein (mol. wt. 250 kDa), while under reducing conditions, three bands corresponding to mol. wt. of 118,75 and 60 kDa were observed. Pretreatment of Mucus-Rs with pronase, trypsin and sodium metaperiodate markedly inhibited bacterial binding. GLC analysis of Mucus-Rs showed it to contain Mannose, Glucose, Galactose, Glucosamine, Galactosamine and Sialic acid as main sugars. Competitive binding in the presence of various sugars and lectins indicated the involvement of mannose in the mucus-bacterial interactions. The Mucus-Rs binding was highly specific for S. typhimurium; no significant binding was seen with E.coliand V. cholerae. Thus, we conclude that S. typhimurium specifically binds to a 250 kDa neutral mucin of intestinal tract. This binding appears to occur via specific adhesin-receptor interactions involving bacterial pili and mannose of neutral mucin.  相似文献   
46.
47.
The present study was designed to determine the changes in serum sodium, anion gap, different antioxidants and free radicals in preeclamptic patients and control subjects. Serum sodium, chloride, bicarbonate, calcium, potassium and magnesium were estimated and anion gap was determined in 100 proteinuric hypertensive and 100 normotensive pregnant women. Mean serum sodium, chloride and bicarbonate level (133.26 ± 13.1, 104.97 ± 11.37, and 22.01 ± 4.66 mEq/l, respectively) were significantly higher in proteinuric hypertensive women as compared to controls (125.85 ± 10.4, 101.90 ± 6.3, 19.34 ± 3.21 mEq/l, respectively) whereas anion gap level (6.28 ± 16.147) was nonsignificantly higher in proteinuric hypertensive as compared to normotensive (4.61 ± 11.84). Total serum sodium concentration increases in preeclamptic subjects, the exact distribution of serum sodium in various compartments of the body are not clear and correlation of serum sodium and anion gap with proteinuria is also not known. The levels of different antioxidants were decreased in preeclamptic patients as compared to the controls while the level of free radicals elevated in preeclamptic subjects as compared to controls. In our study, anion gap level was found to be rather non-significantly higher in proteinuric hypertensive women as compared to normotensive women.  相似文献   
48.
Background Increased levels of TNF-α, IL-6, their soluble receptors, and NT-proBNP have been observed in patients with dilated cardiomyopathy (DCM). In the present study, we assessed the possible involvement of proinflammatory cytokines and their soluble receptors with and without recovery of LV function in DCM patients. Methods and results Forty patients with DCM were enrolled and divided into two groups: Group I consisted of DCM patients (n = 30) whose left ventricular ejection fraction (LVEF) had not recovered on follow up and Group II comprised DCM patients (n = 10) whose LVEF had recovered. Ten healthy subjects were included as controls (Group III). TNF-α, IL-6,TNFR1, TNFRII, gp130, and NT-proBNP levels were significantly increased in Group I and were significantly lower in patients with LVEF recovery as compared to those without recovery of LVEF (P < 0.05). Conclusion Circulating TNF-α, IL-6, and NT-proBNP appear to correlate with the LV function recovery of patients with DCM and could be used as prognostic biomarkers.  相似文献   
49.
Diabetic nephropathy is associated with high morbidity and mortality and the prevalence of this disease is continuously increasing world wide. Though, the major risk factors like hyperglycemia and hypertension play a pivotal role in the pathogenesis of diabetic nephropathy, the etiology of this insidious disorder is not well understood. Mast cells are pluripotent bone marrow derived cells that play a key role in inflammation. Degranulation of mast cells releases various mediators including inflammatory cytokines, endothelins, growth factors, and proteolytic enzymes. Infiltration of mast cells has been noted to occur in renal diseases. In addition, the renal density of mast cells is significantly increased in diabetic patients with nephropathy. It remains unclear whether resident renal mast cells derived mediators play a role in the pathogenesis of diabetic nephropathy. Recent studies suggest the involvement of renal mast cell infiltration and degranulation in diabetic nephropathy. The present review focuses on the role of resident renal mast cells in diabetic nephropathy.  相似文献   
50.
Alpha-lipoic acid (LA) has recently been reported to afford protection against neurodegenerative disorders in humans and experimental animals. However, the mechanisms underlying LA-mediated neuroprotection remain an enigma. Because peroxynitrite has been extensively implicated in the pathogenesis of various forms of neurodegenerative disorders, this study was undertaken to investigate the effects of LA in peroxynitrite-induced DNA strand breaks, a critical event leading to peroxynitrite-elicited cytotoxicity. Incubation of φX-174 plasmid DNA with the 3-morpholinosydnonimine (SIN-1), a peroxynitrite generator, led to the formation of both single- and double-stranded DNA breaks in a concentration- and time-dependent fashion. The presence of LA at 100–1,600 μM was found to significantly inhibit SIN-1-induced DNA strand breaks in a concentration-dependent manner. The consumption of oxygen induced by 250 μM SIN-1 was found to be decreased in the presence of high concentrations of LA (400–1,600 μM), indicating that LA at these concentrations may affect the generation of peroxynitrite from auto-oxidation of SIN-1. It is observed that incubation of the plasmid DNA with authentic peroxynitrite resulted in a significant formation of DNA strand breaks, which could also be dramatically inhibited by the presence of LA (100–1,600 μM). EPR spectroscopy in combination with spin-trapping experiments, using 5,5-dimethylpyrroline-N-oxide (DMPO) as spin trap, resulted in the formation of DMPO-hydroxyl radical adduct (DMPO-OH) from authentic peroxynitrite and LA at 50–1,600 μM inhibited the adduct signal. Taken together, these studies demonstrate for the first time that LA can potently inhibit peroxynitrite-mediated DNA strand breakage and hydroxyl radical formation. In view of the critical involvement of peroxynitrite in the pathogenesis of various neurodegenerative diseases, the inhibition of peroxynitrite-mediated DNA damage by LA may be responsible, at least partially, for its neuroprotective activities.  相似文献   
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