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991.

Background

It remains unclear whether thymidylate synthase (TS), orotate phosphoribosyltransferase (OPRT) and dihydropyrimidine dehydrogenase (DPD) expressions are associated with the pathogenesis of thymic epithelial tumors. Therefore, we investigated the expression of TS, OPRT and DPD in thymic epithelial tumors.

Patients and methods

Fifty-six patients with thymic epithelial tumors were included in this study. Tumors sections were stained by immunohistochemistry for TS, OPRT, DPD, microvessel density (MVD) determined by CD34, and p53. We also conducted in vitro study of TS, OPRT and DPD expression using thymic carcinoma, thymic tumor and thymic fibroblast cell lines.

Results

TS, OPRT and DPD were expressed in 61%, 48% and 41%, respectively. High grade malignancy is significantly associated with higher expression of TS, OPRT and DPD in thymic epithelial tumors. These biomarkers were closely associated with p53 and MVD, and the overexpression of TS and DPD was a prognostic marker for predicting poor outcome in univariate analysis. Our in vitro study showed that marked overexpression of TS and OPRT was observed in thymic carcinoma cells, but not in thymic tumor cells, or thymic fibroblast cells.

Conclusions

The expression of TS, OPRT and DPD was closely related to the grade of malignancy in thymic epithelial tumors. A positive expression of TS, DPD and OPRT might be an important factor in predicting the effectiveness of 5-FU based chemotherapy in this disease.  相似文献   
992.
993.
994.
We examined the inhibitory capacity of dexamethasone (DEX) and cyclosporine (CsA) on T cell activation using various accessory cell (AC)-dependent and AC-independent stimuli. We found that CsA strongly inhibited T cell activation in each of the assays used: allogeneic T cell stimulation, phorbol myristate acetate plus concanavalin A, PMA plus anti-CD3 monoclonal antibody (2C11), or PMA plus ionomycin (IONO) T cell activation. DEX was a potent inhibitor of allogeneic stimulation and of the PMA+Con A- or PMA + 2C11-induced T cell stimulation. PMA + IONO stimulation, however, was not affected by DEX. When inhibition occurred, both drugs suppressed [3H]TdR incorporation, IL-2 production, and IL-2 mRNA accumulation, indicating that the sites of interference of these drugs in the T cell activation pathway are located proximal to IL-2 mRNA accumulation. However, the difference in the effects of DEX and CsA in PMA + IONO stimulation suggests that DEX and CsA differentially affect T cell activation.  相似文献   
995.
PURPOSE: As an approach to evaluate the expression pattern and status of activation of signaling pathways in clinical specimens from head and neck squamous cell carcinoma (HNSCC) patients, we established the Head and Neck Cancer Tissue Array Initiative, an international consortium aimed at developing a high-density HNSCC tissue microarray, with a high representation of oral squamous cell carcinoma. EXPERIMENTAL DESIGN: These tissue arrays were constructed by acquiring cylindrical biopsies from multiple individual tumor tissues and transferring them into tissue microarray blocks. From a total of 1,300 cases, 547 cores, including controls, were selected and used to build the array. RESULTS: Emerging information by the use of phosphospecific antibodies detecting the activated state of signaling molecules indicates that the Akt-mammalian target of rapamycin (mTOR) pathway is frequently activated in HNSCC, but independently from the activation of epidermal growth factor receptor or the detection of mutant p53. Indeed, we identified a large group of tissue samples displaying active Akt and mTOR in the absence of epidermal growth factor receptor activation. Furthermore, we have also identified a small subgroup of patients in which the mTOR pathway is activated but not Akt, suggesting the existence of an Akt-independent signaling route stimulating mTOR. CONCLUSIONS: These findings provide important information about the nature of the dysregulated signaling networks in HNSCC and may also provide the rationale for the future development of novel mechanism-based therapies for HNSCC patients.  相似文献   
996.
For conducting effective risk management in long-stay elderly people at a health service facility, we performed an open case-controlled study to evaluate the effect of the intake of probiotic-fermented milk containing Lactobacillus casei strain Shirota (LcS-fermented milk) on norovirus gastroenteritis occurring in the winter season during the intake period. A total of seventy-seven elderly people (mean age 84 years) were enrolled in the study. During a 1-month period, there was no significant difference in the incidence of norovirus gastroenteritis between the LcS-fermented milk-administered (n 39) and the non-administered (n 38) groups; however, the mean duration of fever of >37°C after the onset of gastroenteritis was 1·5 (SD 1·7) d in the former and 2·9 (SD 2·3) d in the latter group, showing a significant shortening in the former group (P < 0·05). RT-quantitative PCR analysis targeting ribosomal RNA showed both Bifidobacterium and Lactobacillus to be significantly dominant, whereas Enterobacteriaceae decreased in faecal samples from the administered group (n 10, mean age 83 years), with a significant increase in faecal acetic acid concentration. Continuous intake of LcS-fermented milk could positively contribute to the alleviation of fever caused by norovirus gastroenteritis by correcting the imbalance of the intestinal microflora peculiar to the elderly, although such consumption could not protect them from the disease.  相似文献   
997.
The most common renal manifestation of Sj?gren's syndrome is tubulointerstitial nephritis, and glomerular disease is rare (3). A 62-year-old woman with primary Sj?gren's syndrome developed nephrotic syndrome. Kidney biopsy was consistent with membraneous glomerulonephritis. Steroid pulse therapy was not effective. Three months later she was diagnosed with non-Hodgkin's lymphoma of the tongue, and she was given CHOP therapy and radiation. Both the lymphoma and membraneous glomerulonephritis were resolved.  相似文献   
998.
A case of an odontogenic tumor which invaded the intracranial space from the mandible is reported. Judging from the radiographic images it was similar to a malignant tumor. The patient died 17 years after the first visit. According to the final pathological diagnosis, it was malignant odontogenic mixed tumor of low grade which did not belong to any of the WHO classification.  相似文献   
999.
BACKGROUND AND OBJECTIVES: A substantial body of evidence suggests that allogeneic blood transfusion increases the rate of recurrence of resected malignancies. The present study was conducted with the aim of understanding better the clinical characteristics of recurrent esophageal cancer and determining whether any survival advantage is conferred by transfusing autologous instead of allogeneic blood during the esophagectomy for the original malignancy. METHODS: We retrospectively analyzed 123 patients who received blood transfusion while undergoing esophagectomy for thoracic esophageal cancer between January 1991 and February 1998. We focused on those patients in whom the malignancy recurred. Of them, 23 patients received allogeneic blood and 18 received autologous blood. Compared were the clinico-pathological factors influencing prognosis as well as the disease-free survival periods and the period of survival after recurrence of the cancer. RESULTS: The clinico-pathological factors that influenced prognosis were similar in the two groups. There was also no significant difference in the rate at which the esophageal cancer recurred, or in survival time once it had recurred. On the other hand, disease-free survival prior to recurrence was significantly prolonged in the autologous blood transfusion group. CONCLUSION: Use of autologous instead of allogeneic blood prolongs disease-free survival of esophageal cancer patients.  相似文献   
1000.
We describe a boy, 3 years and 6 months old, who experienced a rolandic seizure accompanied by a cluster of atypical absence seizures, the EEGs for which corresponded to those of atypical benign partial epilepsy (ABPE). Of note, this patient suffered from developmental delay beginning in infancy and exhibited giant middle-latency somatosensory evoked potentials with action myoclonus. With the exceptions of ethosuximide, acetazolamide, and adrenocorticotropic hormone, which have been reported to be effective in ABPE, the atypical absence seizures were intractable despite extensive treatment with various anticonvulsants. The drugs that were effective led to a remarkable reduction in seizure frequency and EEG improvement, but the efficacy was temporary. The patient demonstrated moderate mental retardation without regression and could not walk with support or speak any meaningful words at the age of 3 years and 6 months. Based on thorough differential diagnosis, although further studies will be necessary, we propose that this boy may present a new phenotype of ABPE: ABPE with action myoclonus.  相似文献   
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