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281.
The authors argue that "health for all" is not achievable in most countries without health sector reform that incorporates a process of coordinated health and human resources development. They examine the situation in countries in the Eastern Mediterranean Region of the World Health Organization. Though advances have been made, further progress is inhibited by the limited adaptation of traditional health service structures and processes in many of these countries. National reform strategies are needed. These require the active participation of health professional associations and academic training institutions as well as health service managers. The paper indicates some of the initiatives required and suggests that the starting point for many countries should be a rigorous appraisal of the current state of human resources development in health.  相似文献   
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Objective: To evaluate the action of fish liver oil and propolis in pilocarpine epileptic rats treated with the anticonvulsant drug valproate. Methods: Seven groups of rats were treated daily for six months: control; fish liver oil (0.4 ml/kg b.w); propolis (50 mg/kg b.w); pilocarpine-treated rats (epileptic control); epileptic rats treated with valproate (400 mg/kg b.w); groups 6 and 7, epileptic rats treated with valproate plus fish liver oil or propolis. Results: Pilocarpine administration caused a significant increase in hippocampal dopamine and serotonin levels accompanied with a significant decrease in their levels in serum. Lipid peroxidation level and LDH activity in hippocampus were significantly increased after pilocarpine treatment whereas Na+/K+-ATPase activity and total antioxidant capacity were significantly decreased compared to the controls. Animals treated with the combined treatments showed a significant improvement in tested parameters towards the normal values of the control. Conclusion: Fish liver oil and propolis when given in combination with valproate, neuroprotected against the neurophysiological disorders induced by pilocarpine epilepsy in rats.  相似文献   
284.
Systematic studies of the circulation of hepatitis C virus (HCV) recombinants in different parts of the world have been initiated only recently, and no detailed information on this subject is available. The aim of the current investigation was to determine the frequency of HCV recombinants in intravenous drug users (IVDU) from two European countries. HCV RNA from serum samples was tested by RT‐PCR with primers derived from the core and NS5B regions with subsequent sequencing and genotype assignment. The 118 samples from Germany (100%) and 45 out of 47 (96%) sera from Russia demonstrated concordant genotyping results. In the two genotype discrepant sera from Russia 2k/1b recombinants were identified. In order to test the hypothesis that the individuals from the IVDU group might be multiply exposed to various genotypes, 145 out of 165 genotyped serum samples, which were found to be positive for anti‐NS4 antibodies, were serotyped with the Murex HCV serotyping kit that is based on detection of antibodies to type‐specific peptides derived from the NS4 proteins of different HCV genotypes. Discrepancy in genotype and serotype attributions was observed in 11% cases. Retesting of 99 type 1a or 3a samples with a set of type‐ and subtype‐specific primers revealed the presence of a mixed infection only in one case (1a/3a). Thus, the cases of the mixed infection with different HCV genotypes as well as the recombinant forms of HCV are very rare even in such a highly exposed group as IVDU. J. Med. Virol. 82:232–238, 2010. © 2009 Wiley‐Liss, Inc.  相似文献   
285.
AIM: To assess the efficacy and safety of combined pegylated interferon and ribavirin therapy in hepatitis C virus (HCV) infection in renal transplant recipients.METHODS: This is a retrospective chart review of post renal transplant patients who were positive for anti-HCV and HCV-RNA, and who have received treatment with combination of pegylated interferon and ribavirin between October 2003 and December 2008. Only patients with stable graft function and absence of evidence of cirrhosis and who received the therapy for continuous 48 wk were included. Nineteen patients (13 male and 6 female) were identified and included. The patient’s complete blood count, liver and kidney profile, and calculated glomerular filtration rate (GFR) were monitored every 6-8 wk while on treatment. HCV-RNA was tested at 12 wk for early virological response, at 48 wk for end of treatment response (ETR), and then retested at 24, and 48 wk after completion of therapy for sustained virological response (SVR). Liver biopsies were obtained before treatment from all patients and graft kidney biopsies were performed as required.RESULTS: Of the entire cohort, 9 patients (47.4%) showed an ETR and 8 had SVR (42.1%). Of the 8 patients with abnormal alanine aminotransferase (ALT) levels at baseline, 78.9% had their ALT normalized (including the virological non responders). ALT was normal in all responders at the end of therapy and at 24 wk post therapy (100%). Only one patient (5.3%) developed an increase in creatinine and decline in GFR from baseline towards the end of treatment. This patient’s kidney biopsy revealed borderline rejection. There was no impact on response by HCV-genotype, initial HCV RNA load, age or sex of the patient or duration post transplant before commencement of therapy. All patients tolerated treatment in the same way as non-transplant with no unusual or increased occurrence of side effects.CONCLUSION: The combination of pegylated interferon and ribavirin is effective in suppressing HCV-RNA, with a low risk of graft rejection or failure in HCV infected renal transplant recipients.  相似文献   
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287.
We identified an antigen recognized on a human non-small-cell lung carcinoma by a cytotoxic T lymphocyte clone derived from autologous tumor-infiltrating lymphocytes. The antigenic peptide is presented by HLA-A2 and is encoded by the CALCA gene, which codes for calcitonin and for the alpha-calcitonin gene-related peptide. The peptide is derived from the carboxy-terminal region of the preprocalcitonin signal peptide and is processed independently of proteasomes and the transporter associated with antigen processing. Processing occurs within the endoplasmic reticulum of all tumoral and normal cells tested, including dendritic cells, and it involves signal peptidase and the aspartic protease, signal peptide peptidase. The CALCA gene is overexpressed in medullary thyroid carcinomas and in several lung carcinomas compared with normal tissues, leading to recognition by the T cell clone. This new epitope is, therefore, a promising candidate for cancer immunotherapy.  相似文献   
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Interaction of the integrin αE(CD103)β7 expressed on tumor-infiltrating lymphocytes (TIL) with E-cadherin on epithelial tumor cells is required to trigger polarized exocytosis of cytotoxic granules in TIL that elicit tumor cell lysis. In this study, we investigated the functional and signaling properties of CD103 and its individual contribution to T-cell-mediated cancer-cell killing. Our results indicated that the binding of CD103 on tumor-specific CTL to immobilized recombinant E-cadherin-Fc is sufficient to induce the polarization of cytolytic granules, whereas the degranulation of cytolytic granules also requires the coengagement of the T-cell receptor. Moreover, minimal CD103 triggering promotes the phosphorylation of the ERK1/2 kinases and phospholipase Cγ1 (PLCγ1). Inhibiting PLCγ blocks granule relocalization, decreasing T-cell receptor-mediated cytotoxicity. Thus, our results emphasize a unique costimulatory role of CD103 in tumor-specific CTL activation by providing signals that promote T-cell effector functions needed to specifically target and lyse cancer cells.  相似文献   
290.
The relationship between hypoxic stress, autophagy, and specific cell-mediated cytotoxicity remains unknown. This study shows that hypoxia-induced resistance of lung tumor to cytolytic T lymphocyte (CTL)-mediated lysis is associated with autophagy induction in target cells. In turn, this correlates with STAT3 phosphorylation on tyrosine 705 residue (pSTAT3) and HIF-1α accumulation. Inhibition of autophagy by siRNA targeting of either beclin1 or Atg5 resulted in impairment of pSTAT3 and restoration of hypoxic tumor cell susceptibility to CTL-mediated lysis. Furthermore, inhibition of pSTAT3 in hypoxic Atg5 or beclin1-targeted tumor cells was found to be associated with the inhibition Src kinase (pSrc). Autophagy-induced pSTAT3 and pSrc regulation seemed to involve the ubiquitin proteasome system and p62/SQSTM1. In vivo experiments using B16-F10 melanoma tumor cells indicated that depletion of beclin1 resulted in an inhibition of B16-F10 tumor growth and increased tumor apoptosis. Moreover, in vivo inhibition of autophagy by hydroxychloroquine in B16-F10 tumor-bearing mice and mice vaccinated with tyrosinase-related protein-2 peptide dramatically increased tumor growth inhibition. Collectively, this study establishes a novel functional link between hypoxia-induced autophagy and the regulation of antigen-specific T-cell lysis and points to a major role of autophagy in the control of in vivo tumor growth.  相似文献   
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