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Even with the advances of conventional treatment techniques, the nervous system cancer prognosis is still not favorable to the patient which makes alternative therapies needed to be studied. Photodynamic therapy (PDT) is presented as a promising therapy, which employs a photosensitive (PS) agent, light wavelength suitable for the PS agent, and molecular oxygen, producing reactive oxygen species in order to induce cell death. The aim of this study is to observe the PDT action in gliosarcoma cell using a chlorin (Photodithazine, PDZ). The experiments were done with 9L/lacZ lineage cells, grown in a DMEM medium supplemented with 10% fetal bovine serum and 1% penicillin/streptomycin solution and put in a culture chamber at 37 °C with an atmosphere of 5% CO2. The PS agent used was the PDZ to an LED light source device (Biopdi/IRRAD-LED 660) in the 660-nm region. The location of the PS agent was analyzed by fluorescence microscopy, and cell viability was analyzed by MTT assay (mitochondrial activity), exclusion by trypan blue (cell viability), and morphological examination through an optical microscope (Leica MD 2500). In the analysis of the experiments with PDZ, there was 100% cell death at different concentrations and clear morphological differences in groups with and without treatment. Furthermore, it was observed that the photodithazine has been focused on all nuclear and cytoplasmic extension; however, it cannot be said for sure whether the location is in the inside core region or on the plasma membrane. In general, the PDZ showed a promising photosensitive agent in PDT for the use of gliosarcoma.  相似文献   
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Objective: To explore the genetic effect of the GH receptor (GHR) on obesity and related metabolic parameters in Hong Kong Chinese adolescents. Context: Obesity is a growing global epidemic. Increasing evidence suggests that the GH‐IGF‐I axis plays an important role in regulating adiposity and insulin sensitivity. Design: We examined the associations of genetic variants of GHR with serum IGF‐I and IGFBP‐3 levels as well as obesity‐related metabolic traits in Hong Kong Chinese adolescents. Patients: Nine hundred and eighty‐one randomly selected Hong Kong Chinese adolescents from 14 schools. Measurements: We genotyped 17 single nucleotide polymorphisms (SNP) at GHR and measured serum IGF‐I and IGFBP‐3 levels as well as obesity‐related metabolic traits including fasting plasma glucose, insulin and lipid levels. Results: There were significant associations between rs4410646 and the body composition (P = 0·0044) and blood pressure factor scores (P = 0·00017). Carriers of the CC genotype had lower body mass index, percentage body fat, waist and hip circumferences than AC and AA genotype carriers (P = 0·00030–0·0094). There was also association between rs7703713 and the IGF‐I activity factor score (P = 0·0033). The GA and AA carriers of rs7703713 had higher serum IGF‐I, higher serum IGFBP‐3 and higher IGF‐I/IGFBP‐3 molar ratio (P = 0·00069–0·025). Haplotype analysis did not increase the significance of associations. Conclusion: Our results support the role of GHR gene polymorphisms in modulating adiposity and IGF‐I activity in adolescents. Examination of interactions of these SNPs with lifestyle, environmental and perinatal factors may provide further insights into their long‐term effects on obesity and metabolic risks.  相似文献   
84.
Necrotizing granulomatous vasculitis in advanced HIV infection   总被引:1,自引:0,他引:1  
We describe the first case of granulomatous necrotizing vasculitis not restricted to the central nervous system in an HIV-infected patient. No mycobacteria or drugs potentially associated with granuloma formation were involved in this patient, suggesting that the cause of this vasculitis was probably autoimmune. The development of granulomatous vascular inflammation in this patient with less than 200 CD4 cells/microl might have been due to immune overactivation. After starting potent antiretroviral therapy a profound immune deactivation was observed and the vasculitis did not relapse.  相似文献   
85.
OBJECTIVE: Analysis of serum concentrations and modifications of tumor necrosis factor-a (TNF-a), its soluble receptors (TNFR), interleukin 10 (IL-10), and vascular related molecules [soluble vascular cell adhesion molecule 1 (sVCAM-1), vascular endothelial growth factor (VEGF)] after therapy with methotrexate (MTX) and anti-TNF (infliximab) in patients with rheumatoid arthritis (RA). METHODS: Thirty-six patients with RA and 20 healthy controls were included. Patients had been orally taking a stable dose of MTX of at least 12.5 mg/week for a minimum of 6 months before inclusion in the study. Twenty-five patients had shown a clinical response to MTX (MTX Group). The other 11 had shown an unsatisfactory response and presented with active RA; they were selected for additional treatment with infliximab (MTX + IFM Group). Disease activity score (DAS28), hemoglobin concentration, erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), and serum levels of TNF-a, soluble TNFR, IL-10, sVCAM-1 and VEGF were determined at baseline and prior to every infusion of infliximab (3 mg/kg) at 2, 6, 14, 22, and 30 weeks. RESULTS: Although serum levels of TNF-a were similar in patients and controls, patients showed significantly higher concentrations of both soluble TNFR (sTNFR55 and sTNFR75), IL-10, sVCAM-1, and VEGF than healthy individuals. Significantly higher levels of sVCAM-1 and VEGF, but not of the other tested molecules, were detected in those with active disease. After infliximab treatment (MTX + IFM Group) there was a significant decrease in DAS28 and modified Health Assessment Questionnaire scores and ESR and CRP levels. Serum concentration of VEGF showed a significant decrease after infliximab, with levels comparable to those of patients with inactive RA, although VEGF continued to present higher values than in healthy controls. CONCLUSION: Increased levels of vascular related molecules sVCAM-1 and VEGF are serum markers of active RA. The absence of normalization of levels of these molecules in patients with inactive RA could be one of the reasons response to therapy is only temporary.  相似文献   
86.
The antibody response against Leishmania (Leishmania) amazonensis crude antigen was measured through the indirect immunofluorescent assay (IFA) and the immunoenzymatic assay (ELISA) in 114 patients with cutaneous leishmaniasis (CL) in Brazil. Fifty-four patients were infected by Leishmania (Viannia) braziliensis, and 60 patients had L. (V.) guyanensis infection. Patients were comparable by age, sex, disease duration and the Montenegro skin test diameter. L. (V.) braziliensis-infected patients showed significant lower number of ulcerated lesions, greater ulcerated area and higher proportion of lymph node enlargement. Sensitivity of IFA was 79.6% (95% CI 66.1-88.9) and 71.7% (95% CI 58.4-82.2) for L. (V.) braziliensis and L. (V.) guyanensis-infected patients, respectively (P=0.324). Sensitivity of ELISA was 98.2% (95% CI 88.8-99.9) and 85.0% (95% CI 72.9-92.5) for L. (V.) braziliensis and L. (V.) guyanensis-infected patients, respectively (P=0.018). Significant differences were observed in the magnitude of the antibody response before treatment with higher levels detected in L. (V.) braziliensis-infected patients by both serologic techniques. Eighty-four patients had serologic evaluations before and 12 weeks after treatment with meglumine antimoniate, 20 mg/kg/day for 20 days. Significant lower optic density values were observed after treatment with both species independent of cure or failure. Our data showed that L. (V.) braziliensis induces a higher antibody response against L. (L.) amazonensis antigens than L. (V.) guyanensis and that down-modulation of the antibody response occurs shortly during disease evolution after treatment. Moreover the data support the use of ELISA as a better tool for detection of antibodies in CL.  相似文献   
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INTRODUCTION AND OBJECTIVES: To evaluate the clinical characteristics and prognosis of heart failure (HF) development in patients hospitalized for acute myocardial infarction (AMI). PATIENTS AND METHOD: Between May 1990 and March 2000, 836 consecutive patients were admitted with a diagnosis of AMI within 24 h of symptom onset. HF was defined as the presence of rales and a third heart sound with gallop, and evidence of pulmonary congestion on chest x-ray. It was diagnosed in 263 subjects (31.5%). RESULTS: The mean age of patients with HF (group 1) was 63.4 (11.4) years compared with 59.9 (11.6) years in those without HF (group 2) (P<.01). There were differences between groups 1 and 2 in history of diabetes (36% vs 20%; P<.001) or previous HF (9.2% vs 1.1%; P<.001). The reperfusion strategy used in patients with Q-wave infarction, with or without HF, was primary angioplasty in 15% and 14%, respectively (P=.81), and thrombolytic agents in 28% and 37%, respectively (P=.013). Patients with HF were more likely to develop recurrent angina (26.8% vs 19.6%; P=.02), pericarditis (17.5% vs 6.3%; P<.001), and atrial fibrillation (12.3% vs 5.1%; P<.01). In-hospital mortality in groups 1 and 2 was 15.6% and 2.3% (P<.001), respectively, and 10-year survival was 10% and 30%, respectively (P<.001). The variables associated with mortality were: age (HR=1.022; P<.001), hyperglycemia (HR=1.748 per 1.0-g/L increase; P<.001), leukocytosis (HR=1.035 per 1000-cell/.L increase; P<.001), and HF (HR=1.308; P=.028). CONCLUSIONS: AMI is still frequently complicated by HF, which increases short- and long-term morbidity and mortality. Heart failure, age, hyperglycemia, and leukocytosis at admission were independent predictors of mortality during follow-up.  相似文献   
90.
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