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41.
To verify the possible role of human herpesviruses as triggering or aggravating factors in relapsing-remitting multiple sclerosis (RRMS) clinical acute attack, we studied the prevalence of some herpesviruses in the peripheral blood mononuclear cells (PBMCs) collected from 22 MS patients during an MS relapse and in a stable phase and from 18 healthy controls (HC). DNA belonging to Herpes simplex virus type 1 (HSV-1) and type 2 (HSV-2), Human cytomegalovirus (HCMV), Epstein-Barr virus (EBV) and Human Herpes virus 6 (HHV-6) has been searched by specific nested polymerase chain reaction (n-PCR). EBV and HHV6 DNA has been detected with high frequency in acute and stable MS and in healthy controls without significant differences. HCMV DNA was observed both in acute and stable MS but not in HC, and, more interestingly, HSV-1 DNA was only found in 13% of acute MS, while both stable MS and healthy controls were negative. On the basis of these results we focused on HSV-1, and to confirm them and to demonstrate that HSV-1 is actively replicating in MS patients during clinical relapse, we searched both messenger RNA (mRNA) and DNA of HSV-1 in the PBMCs of 15 acute MS patients and 15 healthy controls. We found HSV-1 mRNA and DNA in a significant number of acute MS patients but not in the control group. On the whole these data indicate that HSV-1 reactivate in the peripheral blood of MS patients during clinical acute attack and probably play a role in the triggering of MS relapses.  相似文献   
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Here, we summarize recent data pertaining to the effects of GABAA receptor modulators on the receptor gene expression in order to elucidate the molecular mechanisms behind tolerance and dependence induced by these drugs. Drug selectivity and intrinsic activity seems to be important to evidence at the molecular level the GABAA receptor tolerance. On the contrary, we suggested that all drug tested are equally potentially prone to induce dependence. Our results demonstrate that long-lasting exposure of GABAA receptors to endogenous steroids, benzodiazepines and ethanol, as well as their withdrawal, induce marked effects on receptor structure and function. These results suggest the possible synergic action between endogenous steroids and these drugs in modulating the functional activity of specific neuronal populations. We report here that endogenous steroids may play a crucial role in the action of ethanol on dopaminergic neurons.  相似文献   
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PURPOSE: Stroma cells play a relevant role in tumor development and progression. We investigated the activity of herceptin (HER), a humanized monoclonal antibody widely used for the treatment of HER2-overexpressing epithelial cancer, toward stroma cell lines L87/4 and L88/5. EXPERIMENTAL DESIGN: We studied the antiproliferative potential of HER and role of human serum in HER activity. We also investigated the ability of HER to alter ancillary functions of L87/4 and L88/5, such as support to long-term hematopoiesis, growth factor production, breast cancer cell adhesion, and proliferation. RESULTS: Flow cytometry showed that HER2 membrane expression in L87/4 and L88/5 stroma cells was intermediate between the expression in HER2-negative/dim MCF-7 breast cancer cells and HER2-bright SK-BC3 breast cancer cells. HER2 gene amplification was not detected by fluorescence in situ hybridization in either stromal cell lines. HER significantly inhibited L87/4 and L88/5 proliferation. Mean ID(50)s were found to be 2000 and 1700 micro g/ml for L87/4 and L88/5, respectively, after 3-day exposure and 800 micro g/ml for both cell lines after 9-day exposure. The presence of 10% human serum in the culture increased HER inhibitory activity. IC(50) of stroma cells was found to be intermediate between HER2-bright breast cancer cells (SK-BC3) and HER2-negative/dim breast cancer cells (MCF-7). The drug did not significantly affect the ability of stroma cells to support long-term hematopoiesis in the cobblestone area forming cell assay. In contrast, in coculture assay, MCF7 cells demonstrated a worse adhesion and growth capability on HER-treated stroma layers when compared with untreated stroma. Moreover, HER significantly reduced vascular endothelial growth factor production by L88/5 cells. CONCLUSIONS: Our data support the novel finding that HER may have a relevant activity against stroma cells.  相似文献   
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PURPOSE: p27(Kip1) is a member of the Cip1/Kip1 family of cyclin-dependent kinase inhibitors and is a potential tumor suppressor gene. Low levels of p27 are associated with poor prognosis in a variety of gynecological tumors, including breast, ovarian, and cervical carcinomas. The role of p27 in endometrial cancer remains controversial. EXPERIMENTAL DESIGN: In the present study, p27 protein expression was investigated by immunohistochemistry in a series of 217 endometrial adenocarcinomas and, where present, in synchronous normal endometrium, simple and complex hyperplasia (with or without atypia), and cystic atrophy. The relationship between p27 expression and clinical outcome was also evaluated. RESULTS: Immunohistochemical analysis revealed a significant loss of p27 expression from normal (33%) through hyperplastic endometrium (50%) to endometrial adenocarcinomas (71%; P 相似文献   
45.
Hepatocellular carcinoma (HCC) is an aggressive tumor that often occurs in chronic liver disease and cirrhosis. The incidence of HCC is growing worldwide.With respect to any other available treatment for liver cancer, liver transplantation (LT) has the highest potential to cure. LT allows for removal at once of both the tumor (“seed”) and the damaged-hepatic tissue (“soil”) where cancerogenesis and chronic liver disorders have progressed together. The Milan criteria (MC) have been applied worldwide to select patients with HCC for LT, yielding a 4-year survival rate of 75%. These criteria represent the benchmark for patient selection and are the basis for comparison with any other suggested criteria.However, MC are often considered to be too restrictive, and recent data show that between 25% and 50% of patients with HCC are currently transplanted beyond conventional indications. Consequently, any unrestricted expansion of selection criteria will increase the need for donor organs, lengthen waiting periods, increase drop-out rates, and impair outcomes on intention-to-treat analysis. Management of HCC recurrence after LT is challenging. There are a few reports available regarding the safety and efficacy of sorafenib for HCC recurrence after LT, but the data are heterogeneous. A multi-center prospective randomized controlled trial comparing placebo with sorafenib is advised. Alternatively, a meta-analysis of patient survival with sorafenib for HCC recurrence after LT could be helpful to characterize the therapeutic benefit and safety of sorafenib.Here, we review the use of LT for HCC, with particular emphasis on the selection criteria for transplantation in patients with HCC and management of HCC recurrence after LT.  相似文献   
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Total knee replacement (TKR) is a safe treatment for alleviating pain and restoring physical function in end-stage arthropathy of the knee. First reports of TKR in haemophiliacs date back to the mid-1970s, however detailed information on long-term outcome is scarce. This study evaluated factors influencing the outcome of 116 primary TKRs performed consecutively over 14 years at a single institution. Haemostatic management is discussed in patients with and without inhibitors. Orthopaedic outcome was measured by using the Hospital for Special Surgery knee-rating scale, knee flexion contracture and range of motion. At the end of follow-up period (median duration: 5·1 years) 96 prostheses (83%) were still in place with a 7-year removal-free survival of 81%, similar between human immunodeficiency virus-positive and -negative patients and lower in inhibitor than non-inhibitor patients (44% vs. 87%; P  < 0·05). Sixteen prostheses (14%) were removed for infection (nine) or aseptic loosening (seven) after a median of 4·5 years. Presence of inhibitors, continuous infusion, cementless prostheses and different primary surgeons were associated with an increased risk of infection; however, after adjustment, only primary surgeon was confirmed as an independent risk factor. These results show that TKR represents a safe and effective procedure in haemophiliacs if performed by a highly experienced surgeon.  相似文献   
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