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991.
Choudhary C Gildea TR Salman R Guzman ED Mehta AC 《The Annals of thoracic surgery》2008,85(5):1800-1802
Tracheomediastinal fistula is a rare condition usually associated with a fatal outcome. We report the case of a 65-year-old man with a subcarinal mass causing total destruction of the carina and proximal mainstem bronchi. The mass was diagnosed as a large cell lymphoma, and the decision was made to undertake chemotherapy only after stabilization of the endobronchial tree. The endobronchial defects were successfully palliated with placement of three different types of self-expanding metallic stents using a flexible bronchoscope under conscious sedation. The unique properties of each stent were used for optimum clinical benefit, avoiding any morbidity. 相似文献
992.
Kumar R Bumb RA Ansari NA Mehta RD Salotra P 《The American journal of tropical medicine and hygiene》2007,76(5):896-901
Identification of new foci of cutaneous leishmaniasis (CL), along with reports of Leishmania donovani causing the disease, is an issue of concern. Clinico-epidemiologic analysis of 98 cases in the endemic regions of Rajasthan state, India, suggested the preponderance of infection in men (62.24%) compared with women (37.75%). Species characterization by internal transcribed spacer 1 (ITS1) polymerase chain reaction (PCR)-restriction fragment length polymorphism (RFLP), kDNA-PCR, and immunofluorescence assay established L. tropica as the causative organism. When applied directly to 32 clinical samples, kDNA PCR had a sensitivity of 96.6%, whereas ITS1 PCR had a sensitivity of 82.75%, thus facilitating diagnosis and species identification. Either parasite culture or direct microscopy alone detected 48.2% and 65.5% of the positive samples, respectively, whereas culture and microscopy together improved overall sensitivity to 89.3% (25/28). Except for the kDNA PCR, all other assays were 100% specific. This study provides the first comprehensive molecular and immunologic studies of CL in India. 相似文献
993.
Evaluation of the efficacy and safety of etoricoxib compared with naproxen in two, 138-week randomised studies of patients with osteoarthritis 总被引:1,自引:0,他引:1
Reginster JY Malmstrom K Mehta A Bergman G Ko AT Curtis SP Reicin AS 《Annals of the rheumatic diseases》2007,66(7):945-951
OBJECTIVES: To assess the efficacy and safety of etoricoxib 60 mg once daily and naproxen 500 mg twice daily over a 138-week treatment period in patients with osteoarthritis (OA). METHODS: Two 1-year randomised, double blind, parallel group two-part base studies (part I 12 weeks; part II 40 weeks), followed by an 86-week extension, in patients with OA (hip or knee) were conducted at 80 clinical centres (19 countries). The studies had identical designs. Patients taking placebo in part I received etoricoxib or naproxen (1:1 ratio) in part II and the extension; patients taking etoricoxib or naproxen in part I continued to receive the same treatment throughout the entire length of the studies. Co-primary efficacy end points were patient global assessment of disease status, and WOMAC questionnaire pain subscale and physical function subscale (100 mm VAS). Efficacy over 138 weeks was assessed by graphical analysis. Safety was assessed by observation of adverse experiences and laboratory and physical evaluations. RESULTS: 997 patients entered (615 completed) the base studies. Of these patients, 463 patients entered the extensions. A total of 161 and 152 patients in the etoricoxib and naproxen groups, respectively, completed 138 treatment weeks. Etoricoxib and naproxen showed similar efficacy throughout the 138 weeks of treatment. For etoricoxib and naproxen, respectively, WOMAC pain assessments were 67 and 67 mm (baseline); 28 and 29 mm (1 year), and 34 and 33 mm (138 weeks). Results for the other efficacy end points were similar to those seen with the WOMAC pain assessments. Both etoricoxib and naproxen were generally well tolerated. CONCLUSION: Both etoricoxib and naproxen demonstrated long-term clinical efficacy for the treatment of OA. Etoricoxib and naproxen were generally well tolerated. 相似文献
994.
995.
Deletion of LOX-1 reduces atherogenesis in LDLR knockout mice fed high cholesterol diet 总被引:1,自引:0,他引:1
Mehta JL Sanada N Hu CP Chen J Dandapat A Sugawara F Satoh H Inoue K Kawase Y Jishage K Suzuki H Takeya M Schnackenberg L Beger R Hermonat PL Thomas M Sawamura T 《Circulation research》2007,100(11):1634-1642
Atherosclerosis is associated with oxidative stress and inflammation, and upregulation of LOX-1, an endothelial receptor for oxidized LDL (oxLDL). Here, we describe generation of LOX-1 knockout (KO) mice in which binding of oxLDL to aortic endothelium was reduced and endothelium-dependent vasorelaxation preserved after treatment with oxLDL (P<0.01 versus wild-type mice). To address whether endothelial functional preservation might lead to reduction in atherogenesis, we crossed LOX-1 KO mice with LDLR KO mice and fed these mice 4% cholesterol/10% cocoa butter diet for 18 weeks. Atherosclerosis was found to cover 61+/-2% of aorta in the LDLR KO mice, but only 36+/-3% of aorta in the double KO mice. Luminal obstruction and intima thickness were significantly reduced in the double KO mice (versus LDLR KO mice). Expression of redox-sensitive NF-kappaB and the inflammatory marker CD68 in LDLR KO mice was increased (P<0.01 versus wild-type mice), but not in the double KO mice. On the other hand, antiinflammatory cytokine IL-10 expression and superoxide dismutase activity were low in the LDLR KO mice (P<0.01 versus wild-type mice), but not in the double KO mice. Endothelial nitric oxide synthase expression was also preserved in the double KO mice. The proinflammatory signal MAPK P38 was activated in the LDLR KO mice, and LOX-1 deletion reduced this signal. In conclusion, LOX-1 deletion sustains endothelial function leading to a reduction in atherogenesis in association with reduction in proinflammatory and prooxidant signals. 相似文献
996.
Ghia A Tomé WA Thomas S Cannon G Khuntia D Kuo JS Mehta MP 《International journal of radiation oncology, biology, physics》2007,68(4):971-977
PURPOSE: With the advent of intensity-modulated radiotherapy, the ability to limit the radiation dose to normal tissue offers an avenue to limit side effects. This study attempted to delineate the distribution of brain metastases with relation to the hippocampus for the purpose of exploring the viability of tomotherapy-guided hippocampal sparing therapy potentially to reduce neurocognitive deficits from radiation. METHODS AND MATERIALS: The pre-radiotherapy T1-weighted, postcontrast axial MR images of 100 patients who received whole brain radiotherapy, stereotactic radiosurgery, or a radiosurgical boost following whole brain radiotherapy between 2002 and 2006 were examined. We contoured brain metastases as well as hippocampi with 5-, 10-, and 15-mm expansion envelopes. RESULTS: Of the 272 identified metastases, 3.3% (n = 9) were within 5 mm of the hippocampus, and 86.4% of metastases were greater than 15 mm from the hippocampus (n = 235). The most common location for metastatic disease was the frontal lobe (31.6%, n = 86). This was followed by the cerebellum (24.3%, n = 66), parietal lobe (16.9%, n = 46), temporal lobe (12.9%, n = 35), occipital lobe (7.7%, n = 21), deep brain nuclei (4.0%, n = 11), and brainstem (2.6%, n = 7). CONCLUSIONS: Of the 100 patients, 8 had metastases within 5 mm of the hippocampus. Hence, a 5-mm margin around the hippocampus for conformal avoidance whole brain radiotherapy represents an acceptable risk, especially because these patients in the absence of any other intracranial disease could be salvaged using stereotactic radiosurgery. Moreover, we developed a hippocampal sparing tomotherapy plan as proof of principle to verify the feasibility of this therapy in the setting of brain metastases. 相似文献
997.
Ford JM Seiferheld W Alger JR Wu G Endicott TJ Mehta M Curran W Phan SC 《International journal of radiation oncology, biology, physics》2007,69(3):831-838
PURPOSE: Motexafin gadolinium (MGd) is a putative radiation enhancer initially evaluated in patients with brain metastases. This Phase I trial studied the safety and tolerability of a 2-6-week course (10-22 doses) of MGd with radiotherapy for glioblastoma multiforme. METHODS AND MATERIALS: A total of 33 glioblastoma multiforme patients received one of seven MGd regimens starting at 10 doses of 4 mg/kg/d MGd and escalating to 22 doses of 5.3 mg/kg/d MGd (5 or 10 daily doses then three times per week). The National Cancer Institute Cancer Therapy Evaluation Program toxicity and stopping rules were applied. RESULTS: The maximal tolerated dose was 5.0 mg/kg/d MGd (5 d/wk for 2 weeks, then three times per week) for 22 doses. The dose-limiting toxicity was reversible transaminase elevation. Adverse reactions included rash/pruritus (45%), chills/fever (30%), and self-limiting vesiculobullous rash of the thumb and fingers (42%). The median survival of 17.6 months prompted a case-matched analysis. In the case-matched analysis, the MGd patients had a median survival of 16.1 months (n = 31) compared with the matched Radiation Therapy Oncology Group database patients with a median survival of 11.8 months (hazard ratio, 0.43; 95% confidence interval, 0.20-0.94). CONCLUSION: The maximal tolerated dose of MGd with radiotherapy for glioblastoma multiforme in this study was 5 mg/kg/d for 22 doses (daily for 2 weeks, then three times weekly). The baseline survival calculations suggest progression to Phase II trials is appropriate, with the addition of MGd to radiotherapy with concurrent and adjuvant temozolomide. 相似文献
998.
Distant metastasis is frequently observed in patients with breast cancer and is a major cause of cancer-related deaths in these patients. Currently, very little is known about the mechanisms that underlie the development of the metastatic phenotype in breast cancer cells. We previously found that metastatic breast cancer cells express high levels of tissue transglutaminase (TG2), but established no direct link between TG2 and metastasis. In this study, we hypothesized that TG2 plays a role in conferring the metastatic phenotype to breast cancer cells. The results obtained suggested that increased expression of TG2 in breast cancer cells contributes to their increased survival, invasion and motility. We further found that TG2 protein in a metastatic breast cancer MDA-MB231 cells was present on the cell surface in close association with integrins beta1, beta4 and beta5. Downregulation of endogenous TG2 by small interfering RNA inhibited fibronectin (Fn)-mediated cell attachment, survival and invasion. Conversely, ectopic expression of TG2 augmented invasion of breast cancer cells and attachment to Fn-coated surfaces. We conclude that TG2 expression in breast cancer cells plays an important role in the development of the metastatic phenotype. 相似文献
999.
Andrianifahanana M Singh AP Nemos C Ponnusamy MP Moniaux N Mehta PP Varshney GC Batra SK 《Oncogene》2007,26(51):7251-7261
MUC4 is a transmembrane mucin, which is aberrantly expressed in pancreatic adenocarcinoma with no detectable expression in the normal pancreas. Here, we present a novel mechanism of IFN-gamma-induced expression of MUC4 in pancreatic cancer cells. Our studies highlight the upregulation of STAT-1 as a basis for MUC4 induction and demonstrate that its activation and upregulation by IFN-gamma are two distinct, albeit temporally integrated, signalling events that drive the selective induction of IRF-1 and MUC4, respectively, within a single cell system. The profile of interferon regulatory factor (IRF)-1 gene induction by IFN-gamma is consistent with its rapid transactivation by phospho-Y701-STAT-1. In contrast, the induction of the MUC4 mucin gene expression is relatively delayed, and occurs only in response to an increase in STAT-1 expression. A progressive binding of STAT-1 to various gamma-interferon-activated sequences (GAS) in the MUC4 promoter is observed in chromatin immunoprecipitation assay, indicating its direct association. Stimulation of STAT-1 expression by double-stranded polynucleotides or ectopic expression is shown to induce MUC4 expression, without Y701 phosphorylation of STAT-1. This effect is abrogated by short interfering RNA (siRNA)-mediated inhibition of STAT-1 expression, supporting further the relevance of STAT-1 in MUC4 regulation. In conclusion, our findings identify a novel mechanism for MUC4 regulation in pancreatic cancer cells and unfold new perspectives on the foundation of IFN-gamma-dependent gene regulation. 相似文献
1000.
Mehta R Shah G Leggat JE Hubbell C Roman AM Kittur DS Narsipur SS 《Transplantation proceedings》2007,39(5):1421-1423
The number of overweight and obese patients undergoing renal transplantation has drastically increased in the last two decades. Studies on graft survival and complication rates of these obese patients have had conflicting results, with some reporting a significant risk and others reporting relatively good outcomes. We examined 1-year outcomes in obese and nonobese patients who underwent living donor transplants at our transplant program, a slightly different approach than prior studies of deceased donor transplants into patients with high body mass index (BMI). The mean serum creatinine clearance by the modified MDRD equation at the end of 1 year in the nonobese group was 58.9 mL/min whereas the mean creatinine clearance in the obese group was 48.9 mL/min (P = .09). The length of stay, incidence of delayed graft function, and 1-year graft survival did not differ between the obese and nonobese groups. The results of this single-center experience with living donor transplant into obese subjects suggest no differences in outcomes with regard to surgical or wound complications, delayed graft function, or serum creatinine at 1 year. 相似文献