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31.
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
32.
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
33.
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
34.
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
35.
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
36.
Advances in both access to and the technology underpinning next-generation sequencing have provided a formidable basis for the evaluation of individuals and families recognized as having a potential hereditary cancer. This article focuses on the most clinically relevant hereditary cancer predisposition syndromes such as hereditary breast and ovarian cancer syndromes and hereditary colorectal cancer. It also reviews current best practice in both surveillance for affected individuals as well as an providing an overview of the available risk-reduction strategies for affected individuals. 相似文献
37.
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
38.
Contactins are a group of cell adhesion molecules that are mainly expressed in the brain and play pivotal roles in the organization of axonal domains, axonal guidance, neuritogenesis, neuronal development, synapse formation and plasticity, axo-glia interactions and neural regeneration. Contactins comprise a family of six members. Their absence leads to malformed axons and impaired nerve conduction. Contactin mediated protein complex formation is critical for the organization of the axon in early central nervous system development. Mutations and differential expression of contactins have been identified in neuro-developmental or neurological disorders. Taken together, contactins are extensively studied in the context of nervous system development. This review summarizes the physiological roles of all six members of the Contactin family in neurodevelopment as well as their involvement in neurological/neurodevelopmental disorders. 相似文献
39.
40.
The metabolic syndrome: peroxisome proliferator-activated receptor gamma and its therapeutic modulation 总被引:11,自引:0,他引:11
Gurnell M Savage DB Chatterjee VK O'Rahilly S 《The Journal of clinical endocrinology and metabolism》2003,88(6):2412-2421
By the end of this decade, it has been estimated that between 200 million and 300 million people worldwide will meet World Health Organization diagnostic criteria for diabetes mellitus. This epidemic of predominantly type 2 diabetes has largely been mediated by our shift toward a more sedentary lifestyle predisposing to obesity and insulin resistance. Affected individuals can also exhibit an array of associated undesirable traits such as hypertension, dyslipidemia, and hypercoagulability, leading to morbidity and mortality from atherosclerotic vascular disease. The coexistence of several of these traits with insulin resistance constitutes the metabolic syndrome. Accordingly, improving insulin sensitivity in this group, and thereby potentially ameliorating the excess vascular risk, is a primary goal of treatment. Recent interest has focused on the thiazolidinediones, a novel class of antidiabetic agents, which act as insulin sensitizers and, therefore, potentially target the underlying metabolic disturbance. These agents are high-affinity ligands for the nuclear receptor peroxisome proliferator-activated receptor gamma, and a large body of in vitro and in vivo data has evolved to support their increasing clinical use. Importantly, clinical and laboratory findings in human subjects harboring natural mutations and polymorphisms within the receptor have provided additional insights. Here, we focus on the consequences of inherited variation in the human peroxisome proliferator-activated receptor gamma gene, linking this receptor to disordered glucose homeostasis, adipogenesis, lipid metabolism, and blood pressure regulation. These studies provide further support for the future development of more selective receptor modulators, targeting specific pathways to ameliorate facets of the metabolic syndrome. 相似文献