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41.
Improved growth of human urothelial carcinoma cell cultures   总被引:4,自引:0,他引:4  
From January, 1981 through June, 1982 specimens from 21 patients with bladder (urothelial) cancer were placed in tissue culture, and one long term cell line was established (5%). From July, 1982 through February, 1984, using an improved culture medium, seven long term cell cultures were established from 21 patients (33%). In addition, one long term culture from a patient with a bladder melanoma was established using the standard culture medium. The nine cell cultures were derived from the following types of tumors: transitional cell carcinoma (6), adenocarcinoma (1), squamous cell carcinoma (1) and melanoma (1). All of the cell lines have produced tumors in athymic nude mice except for one transitional cell carcinoma. All of the cultures demonstrate aneuploidy. Homogeneously staining regions have been seen in some cell cultures. A common marker chromosome has not been identified.  相似文献   
42.
Hepatitis C virus mutation affects proteasomal epitope processing   总被引:9,自引:0,他引:9       下载免费PDF全文
The high incidence of hepatitis C virus (HCV) persistence raises the question of how HCV interferes with host immune responses. Studying a single-source HCV outbreak, we identified an HCV mutation that impaired correct carboxyterminal cleavage of an immunodominant HLA-A2-restricted CD8 cell epitope that is frequently recognized by recovered patients. The mutation, a conservative HCV nonstructural protein 3 (NS3) tyrosine to phenylalanine substitution, was absent in 54 clones of the infectious source, but present in 15/21 (71%) HLA-A2-positive and in 11/24 (46%) HLA-A2-negative patients with chronic hepatitis C. In order to analyze whether the mutation affected the processing of the HLA-A2-restricted CD8 cell epitope, mutant and wild-type NS3 polypeptides were digested in vitro with 20S constitutive proteasomes and with immunoproteasomes. The presence of the mutation resulted in impaired carboxyterminal cleavage of the epitope. In order to analyze whether impaired epitope processing affected T cell priming in vivo, HLA-A2-transgenic mice were infected with vaccinia viruses encoding either wild-type or mutant HCV NS3. The mutant induced fewer epitope-specific, IFN-gamma;-producing and fewer tetramer(+) cells than the wild type. These data demonstrate how a conservative mutation in the flanking region of an HCV epitope impairs the induction of epitope-specific CD8(+) T cells and reveal a mechanism that may contribute to viral sequence evolution in infected patients.  相似文献   
43.
Background. B-cell depletion with rituximab, a chimeric anti-CD20antibody, is a novel treatment for refractory and relapsingANCA-associated small-vessel vasculitis. Data are limited andmost reports describe single patients or small numbers of patientsfollowed prospectively. Methods. We report a single-centre experience with 15 patientswho received rituximab for refractory or relapsing ANCA-associatedvasculitis. All patients had been treated with corticosteroidsand cyclophosphamide and a variety of other second-line immunosuppressiveagents. None of the patients had evidence of infection and receivedfour infusions of 375 mg/m2 of rituximab. Disease activity wasassessed in accordance with the Birmingham Vasculitis ActivityScore (BVAS). BVAS, C-reactive protein and ANCA titres wererecorded at baseline and during follow-up. Results. B-cell depletion was achieved in all patients. Partialor complete remission was seen in 14 of 15 patients with a significantdecline in BVAS compared to baseline (P < 0.007). One patientwith granulomatous ANCA-associated vasculitis did not respondto rituximab. There were no side effects during rituximab infusion.Transient leucopenia was observed in two patients. One patientwith bronchial stenosis died of pneumonia 5.5 months after theinitiation of rituximab treatment. One initially anti-HBc-positive/HBsAg-negativepatient experienced a reactivation of hepatitis B, developedend-stage renal failure and died after refusal of dialysis. Conclusions. We report the largest case series of rituximabuse for ANCA-associated vasculitis so far. Our data supportthat the drug is capable of inducing partial or complete remissionin refractory or relapsing patients. Leucopenia and infectiouscomplications remain a matter of concern.  相似文献   
44.
Treatment of hepatitis C after liver transplantation can be challenging as graft rejection and graft hepatitis caused by hepatitis C virus (HCV) may be difficult to distinguish. Immunosuppressive medications may significantly alter the course of hepatitis C in liver transplant recipients. Moreover, single substances have been shown to display antiviral effects in vitro while others are believed to have antifibrotic properties. This review summarizes the modes of action of different classes of immunosuppressive drugs used after liver transplantation and discusses pros and cons of individual drugs in the setting of HCV infection. No definite recommendation for an optimal immunosuppressive regimen can be given at this stage. The most important lesson learned during the last two decades is that acute rejection episodes have to be avoided in particular in hepatitis C since these are associated with reduced graft and patient survival. Further trials are urgently needed to clarify the role of different immunosuppressive compounds in hepatitis C after transplantation.  相似文献   
45.
46.
OBJECTIVE: Acute cryptogenic hepatitis may represent both a self-limited disease as well as the onset of chronic hepatitis. The aim of this analysis was to evaluate the effect of steroid treatment in patients with acute cryptogenic hepatitis. METHODS: We retrospectively analyzed four patients with acute cryptogenic hepatitis. Histories were negative for alcohol and hepatotoxic drug intake. Markers of metabolic liver disease, liver-related autoantibodies, and viral markers were negative in all patients. Gamma globulins were in the normal range. ALT rose above 1000 U/L in all patients and bilirubin levels were elevated to more than 400 micromol/L. Histopathological assessment revealed minimal infiltration with plasma cells, eosinophils and bile duct lesions. Using the international scoring system for the diagnosis of autoimmune hepatitis, all patients were classified as 'probable disease' in the absence of specific markers. RESULTS: We started immunosuppressive treatment with prednisolone because of persisting high aminotransferases and impaired liver function. All patients responded to steroids with normalization of liver function and a rapid decrease of aminotransferases. In one patient, additional treatment with azathioprine was necessary due to rebounding aminotransferases during steroid tapering. CONCLUSION: Steroids have to be taken into account in the therapy for severe acute cryptogenic hepatitis. The response to steroid treatment could be indicative for an autoimmune genesis of the disease.  相似文献   
47.
BACKGROUND: Allograft anterior cruciate ligament reconstruction provides benefits such as earlier return to activities and less pain, but concerns remain regarding potential infection and biomechanical stability. HYPOTHESIS: There is no difference in biomechanical properties of soft tissue allografts treated with the Biocleanse tissue sterilization process compared with irradiated and fresh-frozen allografts. STUDY DESIGN: Controlled laboratory study. METHODS: Thirty-six tibialis anterior allografts were equally divided between Biocleanse, irradiated, and fresh-frozen groups. Grafts were measured for cross-sectional area and looped over a smooth rod with the free sutured ends of the graft fixed in custom clamps. Specimens were tensioned to 10 N for 2 minutes and then loaded between 50 and 300 N for 1000 cycles followed by a failure test. Data for creep (mm); stiffness (N/mm) at cycles 1, 10, 100, and 1000; failure load (N); and failure stress (MPa) were compared with a one-way analysis of variance (P < .05). RESULTS: There were no statistically significant differences in creep between groups. Sterilized groups (irradiated = 144.7 +/- 17.7 N/mm and Biocleanse = 146.5 +/- 28.2N/mm) were significantly stiffer during the first cycle than the fresh-frozen group (117.8 +/- 15.7 N/mm, P < .005) without statistically significant differences for subsequent cycles. There were no differences between groups for either failure load (fresh-frozen = 1665 +/- 291.3 N, irradiated = 1671.9 +/- 290.2 N, Biocleanse = 1651.6 +/- 377.4 N) or failure stress. CONCLUSION: Data for "time-zero" physiologic stiffness and failure loads indicate that the Biocleanse process does not adversely affect the biomechanical properties of the allograft material. CLINICAL RELEVANCE: This novel sterilization technique may provide surgeons with potential allograft material with similar biomechanical properties to native tissue.  相似文献   
48.
Despite new therapeutic approaches patients with advanced oral squamous cell carcinoma still have a dismal prognosis. The main factor contributing to this problem is locoregional failure due to a lack of response to treatment. Several trials have proven the effect of neoadjuvant radiochemotherapy followed by radical surgery in comparison to primary surgery followed by adjuvant radiochemotherapy. No reliable parameters have been identified so far to predict response to radiochemotherapy. The aim of our study was to assess whether podoplanin expression in pretreatment biopsies could serve as a biomarker to predict the host response to neoadjuvant radiochemotherapy.In this retrospective study, podoplanin expression was examined in a set of 63 patients with oral squamous cell carcinoma by immunohistochemistry. We analyzed associations between the level of podoplanin expression and various clinicopathologic parameters, including response to radiochemotherapy, clinical and histological N-status. Furthermore we evaluated the effects of these parameters on overall survival and on locoregional control in univariate and multivariate analysis.The χ2-test revealed that high expression of podoplanin in pretreatment biopsy material was associated with non-regression of the tumor (p = 0.013) and poor overall survival (p < 0.001). Five-year survival rates of 92.9% for patients with weak expression and 15.0% for high expression were revealed. Podoplanin expression was also significantly associated with ypN status (p = 0.004) and ypUICC status (p < 0.001).We concluded that podoplanin might serve as a factor to predict treatment response in oral squamous cell carcinoma treated with neoadjuvant platin-based radiochemotherapy as well as a prognostic factor for overall survival and locoregional control.  相似文献   
49.
BACKGROUND: The elimination of hepatitis B virus surface antigen (HBsAg) is the final goal of hepatitis B treatment, but is rarely achieved. As quantitative assays for HBsAg recently became available, we have investigated whether quantitative HBsAg measurements can substitute for hepatitis B virus (HBV) DNA quantification in treatment monitoring. METHODS: Within this study, 23 liver transplant patients and 18 heart transplant recipients were retrospectively analysed. Patients had been treated with famciclovir and/or lamivudine, in addition some had also received adefovir in cases of lamivudine resistance. Quantitative HBsAg and hepatitis B virus e antigen (HBeAg) levels were determined with the Architect assay. HBV DNA levels were determined with different assays available at given time points. RESULTS: We did not find a significant correlation between either HBsAg or HBeAg and HBV DNA levels - both in treated and untreated patients. More importantly, there was no significant concordance between an increase or decrease of HBsAg or HBeAg with HBV DNA. However, the curve and decline of quantitative HBsAg enabled prediction of eventual viral clearance. Eight patients showed a 2 log10 drop of HBsAg levels and eight patients demonstrated a reduction of HBsAg levels below 100 IU/ml; five patients fulfilled both criteria. Three of those five cleared HBsAg and became positive for antibodies against HBsAg. CONCLUSIONS: Quantitative HBsAg and HBeAg cannot substitute for HBV DNA quantification during the assessment of antiviral therapy; however, the decline of HBsAg does predict eventual HBsAg clearance. A 2 log10 drop to below 100 IU/ml is associated with a high likelihood of HBsAg clearance.  相似文献   
50.
Background/Aims: The incidence of hepatic granulomas is reported in 2–15% of liver biopsies. This study was carried out to evaluate the incidence and aetiology of hepatic granulomas in a German Institute of Pathology with specialization in liver diseases. Methods: A retrospective case review was performed on 12 161 liver biopsies of the Institute of Pathology (University of Cologne) between 1996 and 2004. Aetiology was determined according to histomorphological changes, clinicopathological data and liver tissue polymerase chain reaction (PCR) for detection of diverse putative pathogens in the liver tissue. Results: Four hundred and forty‐two liver biopsies revealed granulomatous lesions (3.63%). Two hundred and fifteen cases (1.77% of all biopsies and 48.64% of granulomatous lesions) were diagnosed as primary biliary cirrhosis. In 37 cases (0.3% of all biopsies and 8.37% of granulomatous lesions), the diagnosis of sarcoidosis was established. A positive PCR result for an infectious pathogen was obtained in 15 samples (3.39%) [Bartonella henselae (n=2), Listeria (n=3), Mycobacterium tuberculosis (n=3), Yersinia pseudotuberculosis (n=1), cytomegalovirus (n=2), Epstein–Barr virus (n=4)]. In six cases, a putative diagnosis was established according to the report of clinical conditions. In 11 cases (2.48%), drugs were the putative causative agent. In 158 cases (36%) a definite diagnosis could not be established. Conclusions: Hepatic granulomas have a broad range of underlying aetiologies. With a combined histological, clinical, serological, and molecular approach, we were able to clarify the cause in 64% of the cases. Owing to the diverse prognosis and therapeutic implications, a detailed interdisciplinary workup of all liver biopsies with granulomatous lesions is mandatory.  相似文献   
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