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991.
The glucocorticoid receptor (GR) and peroxisome proliferator-activated receptors (PPARs) play important roles in both physiological and pathological conditions such as cell differentiation, lipolysis, control of glucose metabolism, immunity, and inflammation. In fact, recent studies suggest that the thiazolidinedione (TZD) class of PPAR-gamma ligands, like glucocorticoids, may also be clinically beneficial in several inflammatory diseases, even if the molecular mechanisms responsible for these activities have not yet been clarified. In this study, by using a murine model of inflammation, the carrageenin-induced paw edema in mouse, we show that the anti-inflammatory activity exhibited by the PPAR-gamma agonists rosiglitazone and ciglitazone is reversed by the GR antagonist RU486 (17 beta-hydroxy-11 beta-[4-dimethylamino phenyl]-17 alpha-[1-propynyl]estra-4,9-dien-3-one). Moreover, by using a conditional GR null cell line, we demonstrate, for the first time to our knowledge, that one of the possible mechanisms explaining the anti-inflammatory activity of TZDs is their ability to activate GR nuclear translocation. In addition, by using J774 cell line lacking PPAR-gamma, we demonstrate that PPAR-gamma expression could not be essential for TZD-mediated GR nuclear translocation, thus explaining, at least in part, the molecular mechanism underlying their anti-inflammatory activity.  相似文献   
992.
Neuronal loss and irreversible brain damage often cause the worsening of symptoms and the decreased efficacy of pharmacological treatment occurring in epileptic patients and animal models of kindling. Recently we reported that the neurotransmitter/neuromodulatory peptide Cholecystokinin-8 (CCK-8) is able to induce the structural and functional neuronal recovery of chemical- and surgical-induced lesions when i.p. injected in rodents. The present study therefore, was aimed at verifying the hypothesis that treatment with a CCK-8 dose having a neuroprotective action might affect brain alterations and the development of kindling in adult rats receiving the convulsant agent pentylenetetrazole (PTZ). Compared to rats receiving Saline prior to PTZ, which manifested clonic-tonic seizures (Class 5 behavioural change scale) after three weeks of treatment, rats pre-treated with CCK-8 showed an improvement of behavioural score exhibiting myoclonus and occasionally tonic seizures (Class 3/4). This decreased susceptibility to develop convulsions was associated with the recovery of PTZ-induced reduction of ChAT levels in forebrain and GABA/GAD expression in the hippocampus. Furthermore, NPY immunoreactivity distribution and NPY mRNA levels were also increased in the hippocampus of rats receiving CCK-8 injection before each PTZ treatment. These data indicate that CCK-8 possesses the ability to prevent and/or suppress the convulsant effects of PTZ by stimulating the synthesis of neurotransmitters/peptides involved in the inhibition of hippocampal hyper-excitability. Our findings suggest that CCK-8 may have anticonvulsant and neuroprotective properties that merit further investigation.  相似文献   
993.
BACKGROUND: The identification of specific morphologic diagnostic criteria is of paramount importance to optimize the accuracy of fine-needle aspiration cytology (FNAC) and to reduce the rate of false-negative results. In the current study, the authors reviewed a consecutive series of false-negative findings observed in the study center to define the presence and degree of cytologic abnormalities. False-negative cases were randomly mixed with true-negative cases and were reviewed by a panel of expert readers in a blinded fashion. The main objective of the current study was to identify a morphologic pattern that may permit the reduction of false-negative findings while maintaining the specificity of FNAC. METHODS: A blind review of a set of 41 consecutive false-negative and 49 true-negative breast aspiration samples was performed by a panel of 10 expert cytologists who were asked to give a final report and to classify the samples according to classic morphologic parameters. RESULTS: The majority final report sensitivity was 54% (range, 19-61%) and specificity was 73% (range, 65-92%). The average concordance with the majority report, adjusted for chance agreement (kappa statistic), was moderate at 0.54 (range, 0.40-0.65). Enlarged nuclear size, a hyperchromatic nucleus, the absence of naked nuclei, and the absence of apocrine metaplasia were reported more frequently in carcinoma cases, although not to a significant extent. The only variable found to be associated significantly (P = 0.041) with a diagnosis of carcinoma was the presence of microcalcifications, which nevertheless were found to occur in only a minority of carcinoma cases (7 of 41 cases) or controls (2 of 49 controls). Multivariate analysis demonstrated that the presence of microcalcifications (odds ration [OR] of 3.0; 95% confidence interval [95% CI], 1.2-7.4), the absence of naked nuclei (OR of 2.4; 95% CI, 1.3-4.4), and enlargement of the nucleus (OR of 1.9; 95% CI, 1.1-3.4) were all independently associated with false-negative findings. Diagnostic accuracy using a morphology-based score did not appear to improve the results substantially compared with the final report (sensitivity of 0.46 vs. 0.54 [P = 0.508] and a specificity of 0.80 vs. 0.73 [P = 0.218]). CONCLUSIONS: The results of the current study confirm that breast FNAC false-negative results are at least partially the result of underreporting of abnormalities that may be noted at review. Detailed analysis of a single morphologic characteristic was found to be of limited diagnostic value, suggesting that operators do perceive abnormalities but cannot translate these findings into distinct morphologic categories.  相似文献   
994.
BACKGROUND: To establish the prognostic value of immune system cells that infiltrate melanoma, the authors evaluated the distribution and density of T lymphocyte subsets, macrophages, and dendritic cells in samples of primary cutaneous melanoma from 47 patients with Stage I and II melanoma according to the American Joint Committee on Cancer staging system. METHODS: Immunohistochemical demonstrations of CD8 and CD4 lymphocytes, CD68 macrophages, human leukocyte antigen-D-related (HLA-DR) cells, S-100 protein, and melanoma-associated antigens Melan A and HMB-45 were performed. The results were derived from independent histopathologic reviews by two pathologists. The low-density, moderate-density, and high-density groups of cells that infiltrated the base of the tumor during the vertical growth phase were compared with the overall survival rate using the Kaplan-Meier method and the log-rank test. Clinical variables (gender, age, tumor location, Clark level, vascular/lymphatic invasion, and thickness) also were analyzed. RESULTS: The CD8 lymphocytes exhibited independent statistically positive significance in survival (log-rank test, 8.49; P = 0.01) between patients in different lymphocyte density groups. There was a difference in 5-year survival among patients in the high-density group (78.8%), the moderate-density group (44.4%), and the low-density group (25.0%). The CD4 lymphocytes, which were less numerous than CD8 cells, had similar distribution. There also was a correlation of HLA-DR cells with overall survival (log-rank test, 5.29; P = 0.02). CD68 cell density was not found to be correlated with survival. CONCLUSIONS: The presence and number of infiltrating CD8 lymphocytes as well as the overall occurrence of HLA-DR cells may be considered independent, favorable prognostic factors in melanoma. The current results may be important for identifying other prognostic factors with which to evaluate disease progression and develop immune therapies for patients with melanoma.  相似文献   
995.
BACKGROUND: Gemcitabine infusion at the fixed dose rate of 10 mg/m(2) per minute (FDR-gemcitabine) has pharmacokinetic advantages and may result in improved therapeutic efficacy. METHODS: Between April 2002 and September 2003, 40 patients with advanced-stage pancreatic adenocarcinoma (PDAC; n = 27) or biliary tree carcinoma (BTC; n = 13) were treated with weekly FDR-gemcitabine (1000 mg/m(2)). The primary end point was the response rate. The secondary end points were progression-free and overall survival (PFS and OS), tumor marker response, and clinical benefit response (CBR). RESULTS: The overall response rate (ORR) on an intent-to-treat basis was 15% (95% confidence interval [95% CI], 4-26%). A positive CBR was obtained in 14 of 29 (48%) patients. Seventeen of 25 (68%) patients had a reduction in carbohydrate antigen 19-9 (CA 19-9) of > 25%. The median time to treatment failure and the median PFS were 17 weeks (95% CI, 13-22 weeks) and 19 weeks (95% CI, 15-23 weeks), respectively. The median OS was 40 weeks (95% CI, 36-45 weeks) and the 1-year actuarial survival rate was 25.8%. Multivariate analysis showed that a performance status score of 0-1 at study entry and locally advanced disease were the only independent predictors of longer PFS and OS, whereas a reduction in CA 19-9 serum levels > 75% was an independent predictor of longer PFS, but had no impact on OS. Toxicity was mild with Grade 3-4 neutropenia (according to the National Cancer Institute-Common Toxicity Criteria [version 2.0]) in 18 of 427 treatment weeks (4.2%), and Grade 3 anemia and thrombocytopenia in 6 of 427 treatment weeks (1.4%) and 9 of 427 treatment weeks (2.1%), respectively, and asymptomatic Grade 3-4 transaminase elevation in 21 of 427 treatment weeks (4.9%). CONCLUSIONS: FDR-gemcitabine at the weekly dose of 1000 mg/m(2) demonstrated promising activity, despite negligible toxicity, in patients with advanced-stage PDAC and BTC.  相似文献   
996.
BACKGROUND: Measuring self-perceived health status and risk perception according to environmental factors remains a major open issue with important health policy implications. METHODS: To measure self-perceived health status in an area where a major thermoelectric plant has been active since 1994, in October 2001, we conducted a two sample survey using the SF-12 Health Survey. The study sample (2001 individuals) representative of the population living in the plant area (Montalto di Castro, Central Italy) was compared with a random sample of the general Italian population (1928 individuals). Mean values were adjusted for age, sex and education. RESULTS: SF-12 summary scales means are comparable in both samples: 50.2 (SE: 0.3) versus 49.9 (SE: 0.3) for the physical score, and 47.7 (SE: 0.4) versus 48.7 (SE: 0.4) for the mental score for Montalto di Castro area and Italian sample respectively. CONCLUSION: People living near a major thermoelectric plant have a subjective health status comparable to that reported by the general Italian population.  相似文献   
997.
Peri-anastomotic graft stenosis is a possible complication of coronary artery bypass graft operations. Early failure of myocardial revascularization may result from graft stenosis with inherent difficulties in perioperative diagnosis and subsequent management. We report the case of a 58-year-old man who experienced early preanastomotic left internal thoracic artery bypass stenosis that progressively resolved during a 2-year period without reoperation or interventional angioplasty. Although the mechanisms underlying graft stenosis remain unclear, this case emphasizes the role of repeated coronary angiography in the choice of treatment.  相似文献   
998.
999.
Left single lung transplantation in a 33-year-old woman affected by end-stage lymphangioleiomyomatosis was complicated by spontaneous and diffuse bleeding from the right lung at the end of the procedure. The right lung was completely deteriorated and the only option to stop the bleeding was a right pneumonectomy. At 14 months after transplantation, the single allograft showed good lung function with acceptable volumes. Single lung transplant and contralateral pneumonectomy can be considered a safe procedure in case of complications related to native lung either in case of lymphangioleiomyomatosis than for other lung diseases (emphysema, cystic fibrosis).  相似文献   
1000.
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