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31.
A C White S K Das B L Fanburg 《American journal of respiratory cell and molecular biology》1992,6(4):364-368
In addition to inhibiting proliferation and causing enlargement of bovine pulmonary artery endothelial cells in culture, porcine platelet transforming growth factor-beta 1 (TGF-beta 1) (2 ng/ml) lowered glutathione (GSH) of these cells by 48% after 96 h in culture when GSH levels were normalized for cell counts. This lowering of cellular GSH was more marked when corrections were made for approximated cell volume. TGF-beta 1 produced only moderate inhibition of pulmonary artery smooth muscle cell proliferation and did not significantly reduce the GSH content of these cells, even at concentrations as high as 8 ng/ml. Elevation of GSH of endothelial cells above control levels by 0.05 mM diethylmaleate or 1 mM cystine prevented the inhibition of cellular proliferation produced by TGF-beta 1. Lowering cellular GSH levels by approximately 85% for 24 to 72 h with 0.01 mM buthionine sulfoximine (BSO) in the absence of TGF-beta 1 had no effect on proliferation or size of the endothelial cells. However, 0.01 mM BSO potentiated the inhibitory effect of TGF-beta 1 on endothelial cell proliferation and in combination with TGF-beta 1 caused cellular detachment at low endothelial cell densities. Thus, although TGF-beta 1 lowers the level of endothelial cellular GSH, this in itself does not appear to account for the inhibition of proliferation and enlargement of these cells produced by TGF-beta 1. Rather, the combination of another unidentified action of TGF-beta 1 in the presence of reduced cellular GSH likely accounts for these effects. 相似文献
32.
Four patients with retrogastric pancreatic pseudocysts were successfully treated by the combined placement of a transgastric external drain and a cystogastric stent. We describe the advantages of using external transgastric drainage along with the cystogastric stent. 相似文献
33.
D M Floyd S D Kimball J Krapcho J Das C F Turk R V Moquin M W Lago K J Duff V G Lee R E White 《Journal of medicinal chemistry》1992,35(4):756-772
As part of a program to discover potent antihypertensive analogues of diltiazem (3a), we prepared 1-benzazepin-2-ones (4). Benzazepinones competitively displace radiolabeled diltiazem, and show the same absolute stereochemical preferences at the calcium channel receptor protein. Derivatives of 4 containing a trifluoromethyl substituent in the fused aromatic ring show potent and long-acting antihypertensive activity. Studies of the metabolism of 4 lead to the metabolically stable antihypertensive calcium channel blockers 5a and 5c. Benzazepinone 5a is a longer acting and more potent antihypertensive agent than the second generation diltiazem analogue TA-3090 (3e). 相似文献
34.
Shyamal K Das Tapas K Banerjee Atanu Biswas Trishit Roy Deepak K Raut Arijit Chaudhuri Abhijit Hazra 《Movement disorders》2007,22(14):2031-2036
An epidemiological study on dystonia has not been reported from India. As part of a major study to find out the prevalence of major neurological disorders in the large urban city of Kolkata, Eastern India, we planned to determine the prevalence of primary dystonia. The study design was a cross-sectional study of a sample population obtained through stratified random selection and conducted in a two-stage procedure of screening by a nonprofessional team followed by confirmation of screened positive cases by the study neurologist. A total population of 52,377 was screened, and 29 subjects with dystonia were diagnosed. Out of them 23 subjects had primary dystonias [crude prevalence rate (CPR), 43.91/100,000; 95% confidence interval (CI), 28.41-64.81; age-standardized rates to world standard population, 49.06 (95% CI,31.74-72.41)] and all cases were focal type and predominantly of limb dystonia variety. Mean onset of dystonias were earlier in women (43.5 years) as compared to men (46.6 years). Thus our study on primary dystonia shows higher prevalence when compared with that of many studies globally, predominantly of focal type, earlier onset among women, and more cases of limb dystonias when compared with more prominent blepharospasm and cervical dystonias in western reports. 相似文献
35.
Endocardial catheter ablation of ventricular tachycardia in patients with ventricular assist devices
Gopi Dandamudi MD Waqas S. Ghumman MD Mithilesh K. Das MD John M. Miller MD 《Heart rhythm》2007,4(9):1165-1169
BACKGROUND: The outcomes of patients with ventricular assist devices (VADs) who undergo catheter ablation for ventricular tachycardia (VT) have not been reported. OBJECTIVE: The purpose of this study was to assess the feasibility, safety, and efficacy of endocardial VT ablation in patients with VADs. METHODS: We retrospectively reviewed three cases at our institution where endocardial catheter ablation was performed in patients with VADs and incessant VT. RESULTS: Three patients with underlying cardiomyopathies and VADs underwent VT ablation for incessant VT refractory to multiple antiarrhythmic medications. In each case, VT was either eliminated or significantly ameliorated by catheter ablation. No procedure-related complications occurred. The hemodynamic stability afforded by the VAD played an important role in facilitating ablation in two of the cases. CONCLUSION: Catheter ablation for VT in VAD patients appears to be feasible, safe, and effective based on our initial experience. Several technical issues, such as decreases in ventricular volumes that can limit maneuverability of the ablation catheter and potential entrapment of the mapping catheter in the inflow cannula, need to be considered at the time of ablation. 相似文献
36.
P K Das A Manoharan S Subramanian K D Ramaiah S P Pani A R Rajavel P K Rajagopalan 《Epidemiology and infection》1992,108(3):483-493
An Integrated Vector Management (IVM) strategy was implemented from 1981 to 1985 in one part of Pondicherry, South India, for the control of the bancroftian filariasis vector Culex quinquefasciatus (the IVM area). The rest of the town (the comparison area) received the conventional larvicidal input. After 1985 both the areas were managed conventionally. The switch to conventional strategy resulted in an increase of vector density in both areas. The microfilaraemia prevalence in humans showed a general decline (P less than 0.05) from 1986 to 1989 only in the IVM area whereas its intensity did not change significantly in either area. While the age-specific rate of gain of infection was generally unchanged in the IVM area, an increase in all age classes was observed after 1985 in the comparison area, where the Annual Transmission Index was high during the previous years. In both areas the rate of loss of infection increased during 1986-9 compared to 1981-6. The results suggest that 3 years is too short a period to relate the changes in entomological parameters to those in the microfilaraemia status of the population. 相似文献
37.
V K Das 《International journal of pediatric otorhinolaryngology》1991,21(2):121-125
The study involves aetiological evaluation of various adverse perinatal causes leading to bilateral sensorineural hearing impairment in children born during the 5-year period of 1981-1985 (inclusive) in the Greater Manchester area of England, United Kingdom. This group comprised over 12% of the total number of hearing-impaired children in the area. Individual possible adverse factors are discussed in the light of present understanding of the pathogenesis and previous reports. 相似文献
38.
S K Brantley S F Davidson M B Johnson P A St Arnold S K Das 《Annals of plastic surgery》1990,25(1):44-47
Investigations into the effects of prior silicone exposure on subsequent capsule formation around silicone implants assume particular relevance in light of the exponential increase in the medical application of polymers such as silicone. The inert nature of silicone has been in question with regard to its effects on the immune system, specifically whether or not it may act as a hapten or antigen. The present study analyzes the effects of prior silicone exposure on subsequent capsule formation, histological consistency, and pressures when an animal is reexposed to a silicone implant. Twelve female Lewis rats (body weight 250 g) were randomly divided into two groups. Group 1 (n = 6) rats were subcutaneously injected with 2.5 ml of Freund's Complete Adjuvant, Group 2 (n = 6) rats were injected with an equal volume of adjuvant sonicated with silicone gel. At 4 weeks a gel-filled silicone implant was placed subcutaneously in each animal. Capsule pressures were obtained at 4 months and the capsules from 3 rats from Group 2 were excised and examined microscopically. Pressures were measured again at 8 months and all remaining capsules were excised and examined. No statistically significant differences were noted when comparing two profiles over time between silicone-exposed and nonexposed animals in regard to capsule thickness or capsule pressure. However, capsule pressures were significantly lower at 8 months than at 4 months in both groups (p less than 0.034). In this model, significant reductions in capsule pressure were noted in both groups over time, but prior exposure to silicone did not appear to alter capsule histology, thickness, or pressure. 相似文献
39.
A single 200-mg dose of clinafloxacin was given orally to each of nine healthy male volunteers, and the concentrations of the drug were measured in plasma, cantharidin-induced inflammatory fluid, and urine over the following 24 h (48 h in the case of urine). The mean maximum concentration in plasma was 1.34 μg/ml at a mean time of 1.8 h postdose. The mean maximum concentration in the inflammatory fluid was 1.3 μg/ml at 3.8 h postdose. The mean elimination half-life of clinafloxacin in plasma was 5.65 h. The overall penetration into the inflammatory fluid was 93.1%, as assessed by determining the ratio of area under the concentration-time curves. Recovery of clinafloxacin in urine was 58.8% by 24 h and 71.8% by 48 h postdose. 相似文献
40.
Cardiac injuries--a clinical and autopsy profile 总被引:3,自引:0,他引:3
P Kulshrestha B Das K S Iyer K A Sampath M L Sharma I M Rao P Venugopal 《The Journal of trauma》1990,30(2):203-207
One hundred two patients sustaining cardiac injuries over a 4-year period were analysed to highlight the natural history of the cardiac injuries. There were 45 blunt, 36 stab, and 21 gunshot injuries. The injury involved the ventricle in 85, atrium in seven, pulmonary artery in five cases, and resulted in crush injury to the heart in the remaining five cases. Thirty-three patients (32.3%) died on the scene and 58 (56.9%) died during the transportation. Only 11 patients (10.8%) reached the hospital alive, and ten of these patients survived following thoracotomy and repair of the cardiac injury. The factors influencing the natural course of cardiac injury were analysed: 2.2% of patients with blunt cardiac trauma reached the hospital alive compared to 19.4% with stab and 14.3% with gunshot injuries; ventricular injuries had a greater prehospital mortality compared to atrial or pulmonary artery injuries; 11.3% of patients sustaining injury to right ventricle reached the hospital alive compared to 3% of those with left ventricular injuries. These data emphasize the need for rapid transport, immediate recognition, and aggressive surgical management, to make a favourable impact on the natural history of cardiac injuries. 相似文献