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41.
Oral mucositis is a common, treatment-limiting, and costly side effect of cancer treatments whose biological underpinnings remain poorly understood. In this study, mucositis induced in hamsters by 5-fluorouracil (5-FU) was observed after cheek-pouch scarifications, with and without administration of RGTA (RG1503), a polymer engineered to mimic the protective effects of heparan sulfate. RG1503 had no effects on 5-FU-induced decreases in body weight, blood cell counts, or cheek-pouch and jejunum epithelium proliferation rates, suggesting absence of interference with the cytotoxic effects of 5-FU. Extensive mucositis occurred in all of the untreated animals, and consisted of severe damage to cheek pouch tissues (epithelium, underlying connective tissue, and muscle bundles). Only half of the RG1503-treated animals had mucositis, over a mean area 70% smaller than in the untreated animals. Basement membranes were almost completely destroyed in the untreated group but was preserved in the RG1503 group. RG1503 blunted or abolished the following 5-FU-induced effects: increases in matrix metalloproteinase (MMP)-2, MMP-9, and plasmin, and decreases in tissue inhibitor of metalloproteinase (TIMP)-1 and TIMP-2. These data indicate that mucositis lesions are related to massive release of proteolytic enzymes and are improved by RG1503 treatment, this effect being ascribable in part to restoration of the MMP-TIMP balance. RG1503 given with cancer treatment might protect patients from mucositis.  相似文献   
42.
We compared histomorphological features and molecular expression profiles of adrenocortical adenomas (ACAd) and carcinomas (ACCa). A critical histopathological review (mean, 11 slides per patient) was conducted of 37 ACAd and 67 ACCa. Paraffin-embedded tissue cores of ACAd (n = 33) and ACCa (n = 38) were arrayed in triplicate on tissue microarrays. Expression profiles of p53, mdm-2, p21, Bcl-2, cyclin D1, p27, and Ki-67 were investigated by immunohistochemistry and correlated with histopathology and patient outcome using standard statistical methodology. Median follow-up period was 5 years. Tumor necrosis, atypical mitoses, and >1 mitosis per 50 high-power fields were factors that were highly specific for ACCa (P <.001). Number (0 to 4) of unfavorable markers [Ki-67 (+), p21 (+), p27 (+), mdm-2(-)] expressed was significantly associated with mitotic activity and morphologic index (i.e., number of adverse morphologic features) and highly predictive of malignancy (P <.001). Ki-67 overexpression occurred in 0 ACAd and 36% ACCa (P <.001) and was significantly associated with mitotic rate and unfavorable morphologic index (P <.001). Tumor necrosis, atypical mitoses, >5 mitoses per 50 high-power fields, sinusoidal invasion, histologic index of >5, and presence of more than two unfavorable molecular markers were associated significantly with metastasis in ACCa. Well-established histopathologic criteria and Ki-67 can specifically distinguish ACCAd from ACCa. Tumor cell proliferation (Ki-67) correlates with mitotic activity and morphologic index. Tumor morphology is a better predictor of metastatic risk in ACCa than current immunohistochemistry-detected cell cycle regulatory and proliferation-associated proteins.  相似文献   
43.
A patient with testis seminoma, sarcoidosis, and neutropenic enterocolitis   总被引:2,自引:0,他引:2  
Seminoma and sarcoidosis do not seem to be associated diseases, judging from epidemiologic data. The presence of these two diseases in the patient whose case is reported may have been coincidental. It was observed, however, that when the testis tumor appeared in this patient, the longstanding sarcoid lesions significantly increased. The patient developed neutropenic enterocolitis after chemotherapy for a non-hematologic malignancy.  相似文献   
44.
Three doses of inactivated hepatitis B vaccine were given at 1-month intervals to 31 hepatitis B surface antigen (HBsAg)-positive Senegalese children aged between 3 and 24 months. A control group of 18 HBsAg-positive Senegalese children received diphtheria-tetanus-polio vaccine. Immunization of HBsAg-positive infants with hepatitis B vaccine was safe but inefficient. After a 12-month follow-up, the prevalence of HBsAg chronic carriers was not significantly reduced in the hepatitis B vaccine group as compared with the control group: 48.4 and 66.7%, respectively. The presence of hepatitis B antigen was found to be a major risk factor for HBsAg-positive children to develop a chronic carrier state. The risk of developing an HBsAg chronic carrier state was also related to advancing age at time of enrollment in the study.  相似文献   
45.
46.
We report a case of acute myeloid leukemia (AML) M1 showing a 48,XY,+13,+13 karyotype. Treatment was according to the Medical Research Council AML14 trial protocol with two courses of DAT chemotherapy. Postchemotherapy bone marrow examination failed to show complete remission or cytogenetic normalization. Despite having resistant disease, the patient initially remained clinically well although requiring regular blood transfusions for anemia. However his leukocyte count gradually increased and he became symptomatic. He was treated subsequently with FLAG but died approximately 2 weeks later, 6 months after first presenting. Tetrasomy 13 as the sole cytogenetic abnormality has not been reported previously in M1 AML and has only been reported in three other AML cases, all with an immature phenotype and poor outcome.  相似文献   
47.
Defects in death receptor-mediated apoptosis have been linked to cancer and autoimmune disease in humans. The in vivo role of caspase 8, a component of this pathway, has eluded analysis in postnatal tissues because of the lack of an appropriate animal model. Targeted disruption of caspase 8 is lethal in utero. We generated mice with a targeted caspase 8 mutation that is restricted to the T-cell lineage. Despite normal thymocyte development in the absence of caspase 8, we observed a marked decrease in the number of peripheral T-cells and impaired T-cell response ex vivo to activation stimuli. caspase 8 ablation protected thymocytes and activated T-cells from CD95 ligand but not anti-CD3-induced apoptosis, or apoptosis activated by agents that are known to act through the mitochondria. caspase 8 mutant mice were unable to mount an immune response to viral infection, indicating that caspase 8 deletion in T-cells leads to immunodeficiency. These findings identify an essential, cell-stage-specific role for caspase 8 in T-cell homeostasis and T-cell-mediated immunity. This is consistent with the recent identification of caspase 8 mutations in human immunodeficiency.  相似文献   
48.
BACKGROUND: Results of conservative management of epithelial ovarian cancer (EOC) remain controversial in the literature. The aim of this study was to assess the clinical outcomes and fertility following fertility-sparing surgical management of EOC in a retrospective multicentre study. METHODS: A multicentre retrospective study was performed by members of two French groups. Six inclusion criteria were defined: (i) Histological review by the same pathologist; (ii) age < or =40 years; (iii) conservative management; (iv) complete peritoneal staging; (v) delivery of a platinum-based chemotherapy in stage > or = IC; and (vi) follow-up >1 year. RESULTS: Thirty-four patients fulfilled the inclusion criteria: 30 had stage IA disease; three had stage IC and one had stage IIA. Eleven patients had recurrence: 10 patients had invasive disease and one had borderline recurrence. Among 10 patients with invasive recurrence, initial stage and grade were: stage IA G1, n = 1; stage IA G2, n = 4; stage IA G3, n = 1; and stage> or = IC, n = 4. All patients with stage > IA had recurrence. Ten pregnancies were observed in nine patients. CONCLUSION: Conservative surgery for patients with EOC could be considered in young patients with stage IA G1 disease. This procedure should not be performed in patients with FIGO stage > IA.  相似文献   
49.
We report on three patients with Costello syndrome and isolated growth hormone (GH) deficiency treated with biosynthetic GH. To our knowledge, these are the only patients with Costello syndrome who have been successfully treated for GH deficiency. We review the pathophysiology of Costello syndrome and highlight the recent recommendations of tumor screening and cardiac surveillance in this population, of particular relevance to those receiving GH therapy.  相似文献   
50.
We have investigated the density of peptides required to elicit different biological responses in cytotoxic T lymphocytes (CTL), including trogocytosis (i.e., the phenomenon whereby the lymphocytes actively capture fragments of plasma membrane from those cells with which they establish an immune synapse). We have used two separate mouse models of CTL recognising defined peptides presented by MHC class I molecules. In both systems, triggering of cytotoxicity and capture of membrane components reached saturation with low densities of ligand. On the other hand, down-modulation of cell-surface levels of TCR, induction of IFN-gamma production and detection of peptide captured required much higher ligand densities. Interestingly, fratricide (i.e., killing between CTL sharing the same specificity), a mechanism proposed to account for CTL exhaustion, was detected only at antigen concentrations still well above that second threshold leading to full blown activation. Taken together, our results show that the different thresholds that govern the elicitation of different CTL functions correlate with different proportions of antigen among the target cell components being captured via trogocytosis.  相似文献   
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