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51.
PURPOSE: The objectives of this study were to evaluate the effect of a cyclooxygenase (COX)-2 inhibitor, nimesulide, on the growth inhibition of s.c. human lung A549 adenocarcinoma tumors and to assess the effect of nimesulide on the expression of COX-2 and peroxisome proliferator-activated receptor (PPAR)-gamma in lung tumors harvested from mice. EXPERIMENTAL DESIGN: Female nu/nu mice were xenografted with s.c. A549 lung tumors, and 1 day after tumor implantation, the mice were fed with a diet containing nimesulide at 250-1500 ppm doses. Tumor dimensions were monitored twice weekly, and tumor samples isolated from mice were used to determine prostaglandin E(2) (PGE(2)) levels by enzyme immunoassay, expression of COX-2 and PPAR-gamma by Western blotting and immunohistochemistry. Furthermore, the induction of apoptosis in tumor specimens was determined by terminal deoxynucleotidyl transferase-mediated nick end labeling staining. RESULTS: Nimesulide treatment showed a dose-dependent growth-inhibitory effect of A549 tumors with a maximum of 77.7% inhibition at 1500 ppm of nimesulide. Western blotting experiments showed similar expression of COX-2 in both control and nimesulide (250-1500 ppm)-treated mice tumor tissues. PPAR-gamma was found to be overexpressed as a result of 1500 ppm nimesulide treatment and was not detected in tumors from control or 250-1000 ppm nimesulide-treated mice. Nimesulide (1500 ppm) significantly reduced intratumor PGE(2) levels (P < 0.001) and induced apoptosis in 25% of tumor cells as compared with control tumors. CONCLUSIONS: Nimesulide (1500 ppm) induced growth inhibition of A549 lung tumors is associated with the reduction of intratumor PGE(2) levels but without affecting the expression of COX-2. Nimesulide-induced enhancement of the expression of PPAR-gamma may also contribute to its antitumor effect, which needs to be further investigated. 相似文献
52.
The objective of this study is to find the role of nitric oxide (NO) in the haemodynamics of mice subjected to heat stress caused by Whole Body Hyperthermia (WBH) treatment. L-arginine (L-arg), a natural substrate for NO synthase (NOS), N-nitro-L-arginine methyl ester (L-NAME), a preferential inhibitor of endothelial NOS, and dexamethasone, a preferential inhibitor of inducible NOS, have been used to study the role of NO in thermal injury caused by WBH treatment. Nitrite in plasma and mortality of Swiss male mice subjected to WBH treatment induced by radiant heat (40 degrees C fo 1 h at 50-55% relative humidity), were monitored in mice pre-treated with either L-NAME, dexamethasone or L-arg. A batch of mice subjected to 24 h fasting prior to WBH treatment was also used to study the above parameters. Injections with 1.5 mg/kg or above of L-NAME just before WBH treatment, induced mortality in mice, with a corresponding drop in plasma nitrite values. L-arg (8 mg/kg) pre-treatment reversed the killing caused by L-NAME in WBH treated mice. L-arg (60 mg/kg) pre-treatment induced mortality in mice subjected to WBH treatment. In the fasted group, a very low dose of L-arg (8 mg/kg) given before WBH treatment led to a significant increase in plasma nitrite levels. In both the normal and fasted groups of mice, 120 mg/kg of L-arg pre-treatment resulted in a sharp increase in plasma nitrite values and subsequent death of mice. The results throw up an important finding, in that the interaction of elevated body temperature, with either a decrease or over production of nitrite oxide, leads to modulation of thermal injury of mice, caused by WBH treatment. 相似文献
53.
Surgical management of complications after transcatheter closure of an atrial septal defect or patent foramen ovale 总被引:2,自引:0,他引:2
Berdat PA Chatterjee T Pfammatter JP Windecker S Meier B Carrel T 《The Journal of thoracic and cardiovascular surgery》2000,120(6):1034-1039
OBJECTIVE: During recent years, transcatheter closure has become an alternative to operations for the treatment of atrial septal defects and patent foramen ovale. However, this procedure may be unsuccessful or complicated and requires surgical treatment. METHODS: We retrospectively analyzed the outcomes of patients who needed surgical treatment after failed or complicated transcatheter closure of an atrial septal defect or a patent foramen ovale. RESULTS: Between April 1994 and March 1999, 124 patients were treated with transcatheter closure of an atrial septal defect or a patent foramen ovale at our institution. We report the results of 10 (8%) patients of this series who required operations after transcatheter closure attempts. In 8 of these 10 patients a significant shunt caused by malposition or dislocation of the device persisted, leading to surgical closure of the defect. In 2 patients injury of the femoral artery at the puncture site required surgical repair. In one patient the device had to be removed surgically from the iliac vein after retraction. One patient died of left ventricular perforation after dislocation of the device and several surgical attempts to close the left ventricular rupture. All other patients recovered well. CONCLUSION: An operation was required after transcatheter closure of an atrial septal defect or a patent foramen ovale in 8% of patients. After device complications, the atrial septal defect and the patent foramen ovale can still successfully be closed surgically with good results and low morbidity. However, serious complications like cardiac perforation may have a fatal outcome. Residual shunt, dislocation, or vascular complications are the most frequent problems that require surgical interventions. 相似文献
54.
Kapoor L Gan MD Bandyhopadhyay A Das MB Chatterjee S 《The Annals of thoracic surgery》2000,69(1):291-292
We describe an alternative step in the transatrial approach to the repair of ventricular septal defects. We temporarily detach the chorda of the obscuring tricuspid valve from its attachment to the septum to expose the ventricular septal defect. 相似文献
55.
Steffen Robert Tornieporth Nadia Costa Clemens Sue-Ann Chatterjee Santanu Cavalcanti Ana-Maria Collard Françoise De Clercq Norbert DuPont Herbert L. von Sonnenburg Frank 《Journal of travel medicine》2004,11(4):231-238
Background Recent epidemiologic data on travelers— diarrhea (TD) are essential for the evaluation of conventional and future prophylactic and therapeutic measures.
Methods To determine the epidemiology, including risk factors, impact and quality-of-life evaluation of TD, a cross-sectional survey was conducted over 12 months at the airports of Mombasa (Kenya), Goa (India), Montego Bay (Jamaica) and Fortaleza (Brazil) by distributing questionnaires to visitors just prior to their flying home. The study period was March 1996 to July 1998.
Results Overall, 73,630 short-term visitors completed a questionnaire. The total diarrhea attack rate varied between a high of 54.6% in Mombasa and a low of 13.6% in Fortaleza, but only between 31.5% and 5.4% of all travelers had classic TD. The 14-day incidence rates varied between 19.5% and 65.7%. Few travelers meticulously avoided potentially dangerous food items, although in India and Kenya most travelers avoided those considered most dangerous. Risk factors were stays exceeding 1 week, age between 15 and 30 years, and residence in the UK. The impact, measured as incapacity or quality-of-life scores, was very considerable.
Conclusions TD continues to affect vacationers and business travelers as frequently as it did some 20 years ago. Compliance with recommendations to reduce exposure to pathogens by avoiding dangerous food items is poor among travelers from all countries. Implementation of food safety education programs may be difficult to achieve. 相似文献
Methods To determine the epidemiology, including risk factors, impact and quality-of-life evaluation of TD, a cross-sectional survey was conducted over 12 months at the airports of Mombasa (Kenya), Goa (India), Montego Bay (Jamaica) and Fortaleza (Brazil) by distributing questionnaires to visitors just prior to their flying home. The study period was March 1996 to July 1998.
Results Overall, 73,630 short-term visitors completed a questionnaire. The total diarrhea attack rate varied between a high of 54.6% in Mombasa and a low of 13.6% in Fortaleza, but only between 31.5% and 5.4% of all travelers had classic TD. The 14-day incidence rates varied between 19.5% and 65.7%. Few travelers meticulously avoided potentially dangerous food items, although in India and Kenya most travelers avoided those considered most dangerous. Risk factors were stays exceeding 1 week, age between 15 and 30 years, and residence in the UK. The impact, measured as incapacity or quality-of-life scores, was very considerable.
Conclusions TD continues to affect vacationers and business travelers as frequently as it did some 20 years ago. Compliance with recommendations to reduce exposure to pathogens by avoiding dangerous food items is poor among travelers from all countries. Implementation of food safety education programs may be difficult to achieve. 相似文献
56.
57.
Kasturi Sanyal Mita Chatterjee Debnath 《Journal of labelled compounds & radiopharmaceuticals》2012,55(7):258-263
Protection of the thiolate function of dimercaptosuccinic acid (DMSA) and ethylenedi‐l ‐cysteine diethyl ester (ECD) by S‐thiomethylation allowed automatic deprotection during technetium‐99m (99mTc) radiolabelling by direct reduction with stannous chloride dihydrate. Protection of the free thiolate group increased the stability of the ligands as well as deprotection during complexation, which resulted in the desired radiopharmaceuticals. The complexes obtained from the protected ligands were chromatographically (HPLC) and biologically compared with the corresponding 99mTc complexes of the unprotected ligands. The results suggest that the aforementioned method of protection by S‐thiomethylation could be utilized for the development of single‐vial DMSA and ECD kit. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
58.
Uttam Kumar Sarkar Utpala Mitra Mamta Chawla Sarkar Shanta Dutta Himanish Roy Mrinal Kanti Chatterjee Phalguni Dutta 《急性病杂志》2012,1(2):165-167
Horizontal transmission of H1N1/09 virus infection is very common however; transmission through this route has not been reported in newborns. To our knowledge, this is the first case report of newborn who acquired infection of novel H1N1/09 virus horizontally through asymptomatic family members or hospital staff during epidemic period in Kolkata, India. Baby recovered without antiviral therapy but received antibiotic for bacterial co-infection. 相似文献
59.
Mohammed Sultan Ul Hassan Justin Sanjay Chatterjee Zeiad Alshameeri 《European journal of plastic surgery》2012,35(8):599-605
Surgical drains are commonly used in plastic surgery. Drains are subsequently removed at arbitrary volumes depending on local protocols. The rational for when to remove a drain has not been scientifically determined. We compared removal of drains at ≤30?ml/24?h vs. ≤50?ml/24?h for 158 wounds, in 90 patients. Postoperative complications, length of hospital stay and resulting cost–benefit were considered. Prospective data were collected for two consecutive similar cohorts of patients undergoing abdominoplasty, bilateral breast reduction and breast augmentation. In the first cohort, drains were removed when drainage was ≤30?ml/24?h and the second cohort when ≤50?ml/24?h. Demographics, days of drainage, surgeon grade and duration of postoperative hospital stay were recorded. Patient records were then analysed and complications recorded, including haematoma, infection, seroma, wound breakdown and fat necrosis. The median postoperative stay for all three operations for both drainage cohorts was similar with no statistically significant difference; however, the drainage time in breast augmentation was significantly less in the <50?ml/24?h group. There were no significant differences in outcome measures between the patients undergoing abdominoplasty, breast reduction or breast augmentation. Drain removal at ≤50 vs. ≤30?ml/24?h did not result in an increase in postoperative morbidity or adverse outcome in any of the three different operation types. 相似文献
60.