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61.
We have previously demonstrated that normal human T cells either long-term repeatedly stimulated or freshly activated in vitro in the presence of TGF-beta express the cell surface T-cell costimulating molecule OX40 ligand (OX40L). To further elucidate the kinetics of OX40L expression by human T cells, we have examined whether cell proliferation was required for the expression of OX40L. Thus, normal fresh peripheral blood mononuclear cells were stimulated with immobilized anti-CD3 antibody in the presence of the DNA synthesis-blocking agents such as mitomycin C, 5-fluorouracil, or X-ray irradiation. Flow cytometric analyses demonstrated that a significant frequency of these DNA-damaged activated primary CD4(+) and CD8(+) T cells became OX40L(+) as early as 1 hour after treatment. The OX40L induction on the DNA-damaged activated T cells was inhibited by treatment with either RNA or protein synthesis inhibitors, actinomycin D, or cycloheximide, respectively. Induced OX40L on T cells was functional because it bound recombinant OX40. These data indicate that human primary T cells are programmed to rapidly express functional OX40L molecules after stimulation under DNA-damaging conditions, demonstrating that the induction of OX40L by T cells is independent of cell proliferation. The clinical implications of these new findings are discussed.  相似文献   
62.

Objective

We analyzed a large number of stage I clear cell carcinoma of the ovary (CCC) patients to estimate the survival impact of the capsule status in stage I CCC patients, particularly in comparison with non-CCC patients.

Methods

Clinicopathologic data on 564 patients with stage I epithelial ovarian cancer (EOC) collected under the central pathological review system were subjected to uni- and multivariable analyses to evaluate the disease-free survival (DFS) and overall survival (OS).

Results

There was no significant difference in both the OS and DFS of CCC patients between IA and IC(ir) (intraoperative capsule rupture) {IA vs. IC(ir); OS: P = 0.1402, DFS: P = 0.2701}. In contrast, CCC patients at IC(non-ir) {IC excluding for IC(ir), such as preoperative capsule rupture, positive ascites/washing, and surface involvement} showed a poorer OS and DFS than those at IC(ir), or those at the corresponding stage in non-CCC. In multivariable analysis, the capsule status was an independent prognostic factor of a poor OS and DFS {OS: HR, 2.832; 95% CI 1.156-6.938; P = 0.023; DFS: HR, 4.327; 95% CI, 1.937-9.667; P = 0.0004)} {In contrast, non-CCC: N.S. (OS/DFS)}. Furthermore, in CCC patients, intraperitoneal recurrences were more frequently observed in IC(non-ir) CCC than IA or IC(ir) CCC (P = 0.0083) {In contrast, non-CCC: N.S.}.

Conclusion

This study suggests that CCC patients other than those with intraoperative capsule rupture show a considerable risk for mortality despite adjuvant chemotherapy.  相似文献   
63.
To establish an effective cancer immunotherapy, it is crucial that cancer cells present a cancer‐specific antigen in a hypoxic area, a hallmark of the tumor microenvironment. Here, we show the impact of hypoxia on MHC class I antigen presentation in vitro and in vivo in murine tumors. Activation of antigen‐specific CTLs by tumor cells that had been pre‐incubated under a condition of hypoxia was enhanced compared with that by tumor cells pre‐incubated under a condition of normoxia. Cell surface expression of MHC class I‐peptide complex on the tumor cells was increased under a condition of hypoxia, thereby leading to higher susceptibility to specific CTLs. We show that the hypoxia‐inducible ER‐resident oxidase ERO1‐α plays an important role in the hypoxia‐induced augmentation of MHC class I‐peptide complex expression. ERO1‐α facilitated oxidative folding of MHC class I heavy chains, thereby resulting in the augmentation of cell surface expression of MHC class I‐peptide complex under hypoxic conditions. These results suggest that since the expression of MHC class I‐peptide complex is augmented in a hypoxic tumor microenvironment, strategies for inhibiting the function of regulatory T cells and myeloid‐derived suppressor cells and/or immunotherapy with immune checkpoint inhibitors are promising for improving cancer immunotherapy.  相似文献   
64.
The filamentous fungus Coleophoma empetri F-11899 produces an echinocandin-like compound FR901379, the original source for micafungin which is prescribed to treat deep-seated mycoses. Despite its industrial importance, no genetic information on C. empetri F-11899 is currently available. To characterize FR901379 biosynthetic genes by insertional mutagenesis and to improve the compound production genetically, Agrobacterium tumefaciens-mediated transformation (ATMT) was attempted to make genetic manipulation possible in this strain. The optimum conditions for ATMT of C. empetri were determined for the cell density of bacteria, time period of co-cultivation and types of filters in co-cultivation. Using the established ATMT method, the hygromycin B resistant gene was successfully transferred into the genome of C. empetri F-11899 and stably maintained even after a serial passage. Some of these results will be applicable for ATMT of various filamentous fungi.  相似文献   
65.
A deficiency of citrin, which is encoded by the SLC25A13 gene, causes both adult-onset type II citrullinemia (CTLN2) and neonatal intrahepatic cholestasis (NICCD). We analyzed 16 patients with NICCD to clarify the clinical features of the disease. Severe intrahepatic cholestasis with fatty liver was the most common symptom, but the accompanying clinical features were variable, namely; suspected cases of neonatal hepatitis or biliary atresia, positive results from newborn screening, tyrosinemia, failure to thrive, hemolytic anemia, bleeding tendencies and ketotic hypoglycemia. Laboratory data showed elevated serum bile acid levels, hypoproteinemia, low levels of vitamin K-dependent coagulation factors, and hypergalactosemia. Hypercitrullinemia was detected in 11 out of 15 patients examined. Most of the patients were given a lactose-free and/or medium chain triglycerides-enriched formula and lipid-soluble vitamins. The prognosis of the 16 patients is going fairy well at present, but we should observe these patients carefully to see if they manifest any symptom of CTLN2 in the future.  相似文献   
66.
In squamous cell carcinoma (SCC) of the esophagus, D2-40 immunostaining has recently been used to detect lymphatic invasion, but invasion detected using D2-40 immunostaining for a predictor of nodal metastasis was controversial. Therefore, the usefulness of detecting lymphatic invasion by D2-40 immunostaining as a predictor of nodal metastasis was examined in superficial (mucosal and submucosal) SCC of the esophagus. A total of 115 superficial SCC of the esophagus were examined on immunohistochemistry using D2-40. It was found that lymphatic invasion demonstrated on D2-40 immunostaining was mainly detected in the lamina propria mucosa. Lymphatic invasion was found in 37 cases and the invasion detected in the entire tumor tissue was statistically correlated with nodal metastasis. Based on the lymphatic invasion according to D2-40 immunostaining, an algorithm was devised for the risk (low, intermediate and high) of nodal metastases in superficial SCC in the esophagus. In conclusion, the detection of lymphatic invasion on D2-40 immunostaining in tumor tissue is a strong predictor for nodal metastasis in superficial SCC of the esophagus. Lymphatic invasion was found mainly in the lamia propria mucosa, thus the devised algorithm is useful for determining the optimal treatment strategy after endoscopic mucosal resection for esophageal SCC.  相似文献   
67.
We studied the expression of cell cycle regulators and growth factor-receptor systems in gastric carcinoma in young adults and tried to clarify the specific alterations associated with H. pylori. We studied 33 young patients (18-29 years old, mean age 26.4) with gastric carcinoma. The patients were classified into two groups according to the degree of atrophic gastritis. Then we examined the expression of p53, cripto, cyclin-E, c-met, c-erbB2 and TGF-alpha immunohistochemically and compared the results between the two groups. The results were compared with 66 sex-, tumor histology-, and depth-matched elder controls (36-86 years old, mean age 64.0). H. pylori was judged by Giemsa staining. Seventeen patients had atrophic changes in the corpus (Group A), while 16 showed superficial gastritis or normal mucosa (Group S). All 17 patients of Group A showed H. pylori infection, while the 3 of the 16 members of Group S did not have H. pylori. p53 overexpression was observed more frequently in Group S (88%) than in Group A (41%, p<0.05). In the 3 patients without H. pylori infection, all carcinoma specimens showed p53 overexpression. Overexpression of cyclin-E was detected in 4 patients from Group S. On the other hand, cripto was observed more frequently in Group A than in Group S. No obvious differences were observed in c-erbB2, TGF-alpha and c-met expression. Overall, p53 overexpression was detected more frequently in younger than in older patients, whereas cripto expression was less detected. These results suggest that p53 and cyclin-E may act in an H. pylori-independent or -adjunctive manner for gastric carcinogenesis. Cripto expression might be correlated tightly with H. pylori infection.  相似文献   
68.
Restriction fragment length polymorphisms of the vitamin D receptor gene have recently been reported to be associated with changes in bone mineral density. Alterations in systemic calcium balance and Ca-regulating hormones such as 1,25(OH)2 vitamin D3 and parathyroid hormone have been demonstrated in essential hypertension. We investigated the relationship between polymorphisms of the vitamin D receptor gene and systemic Ca metabolism in patients with essential hypertension and in normotensives. We compared 147 subjects with essential hypertension and 100 normotensive control subjects. The genotype distribution and derived allele frequencies for the vitamin D receptor gene were similar in the two groups (genotype bb/Bb/BB and allele B/b: 60.1/32.6/7.2 and 0.24/0.76 in hypertensives vs. 56.0/36.0/8.0 and 0.26/0.74 in normotensive subjects). Serum concentrations of total Ca in the bb, Bb, and BB groups were, respectively, 4.5+/-0.3 vs. 4.5+/-0.4 vs. 4.4+/-0.5 mmol/l in normotensives and 4.6+/-0.3 vs. 4.6+/-0.4 vs. 4.4+/-0.5 mmol/l in hypertensives. Ionized Ca levels were 1.17+/-0.04 vs. 1.16+/-0.04 vs. 1.15+/-0.04 mmol/l in normotensives and 1.16+/-0.04 vs. 1.16+/-0.04 vs. 1.14+/-0.05 mmol/l in hypertensives, respectively. These results indicate that the BB genotype of the vitamin D receptor gene is associated with lower serum Ca levels but is not a useful predictive marker for the development of essential hypertension in Japanese subjects.  相似文献   
69.
70.
Purpose Cardiac scintigraphic studies using 123I-labeled metaiodobenzylguanidine ([123I]MIBG) have demonstrated heterogeneous myocardial accumulation of MIBG in diabetes. The accumulation has been found to correlate with a heterogeneous decrease in the expression of norepinephrine transporter (NET). In diabetic peripheral nerve tissue, polyol pathways are activated and cause nerve dysfunction and degeneration. However, there has been little research on the polyol pathway and cardiac sympathetic nerves. Therefore, to assess the influence of the polyol pathway on cardiac sympathetic nervous function, we investigated the regional accumulation of MIBG and NET protein expression in diabetic model rats treated with aldose reductase inhibitor (ARI) for the blockade of polyol pathways.Methods Rats were given a single intravenous injection of streptozotocin (n=76, STZ-D rats). Starting the day after STZ injection, ARI was administered daily to 42 of the rats for 4 weeks (ARI-D rats). To assess the cardiac sympathetic nervous function, [125I]MIBG autoradiographic experiments were carried out. Finally, NET protein expression was assessed with a saturation binding assay.Results The myocardial sorbitol concentration was significantly higher in STZ-D rats than in ARI-D rats. There was no heterogeneous accumulation of MIBG in ARI-D rats. There was a heterogeneous decrease of NET expression in STZ-D rats, but not in ARI-D or control rats.Conclusion The gathered data indicate that the enhanced polyol pathway correlates with the decrease in regional cardiac sympathetic nervous function, and this impairment may lead to the reduction of NET protein in cardiac sympathetic nerves of the diabetic inferior wall.An erratum to this article can be found at  相似文献   
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