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61.
62.
Bone marrow stem cells develop into haematopoietic and mesenchymal lineages, but have not been known to participate in steroidogenic cell production. Steroidogenic factor 1 (SF-1), also designated adrenal 4 binding protein (Ad4BP), is an essential orphan nuclear receptor for steroidogenesis as well as for adrenal and gonadal gland development. In the present study, we revealed that the adenovirus-mediated forced expression of SF-1 can transform cultured primary long-term cultured bone marrow cells into steroidogenic cells, showing the de novo synthesis of multiple steroid hormones in response to adrenocorticotropic hormone (ACTH). This finding may provide an initial step in innovative autograft cell transfer therapy for steroid hormone deficiencies.  相似文献   
63.
The p16INK4a tumour suppressor gene, encoding p16 protein, plays a crucial role in regulation of the G1 cell-cycle phase. To investigate the potential role of p16 in soft tissue leiomyosarcoma (LMS), an immunohistochemical analysis was performed of 77 LMSs for p16 expression. Decreased expression of the p16 protein was identified in 25 of 77 LMSs (32%). Decreased expression of p16 correlated significantly with large tumour size (p=0.0038). In a univariate analysis, large tumour size and decreased expression of p16 were statistically significant adverse prognostic factors (p=0.025 and p=0.0021, respectively). In a multivariate analysis including conventional clinicopathological parameters, decreased expression of p16 protein was revealed as the only independent unfavourable prognostic factor (p=0.012). To elucidate the mechanisms of inactivation of the p16INK4a gene, 49 LMSs for which genomic DNA was available were examined; analysis for homozygous deletion, mutation, and promoter hypermethylation was conducted using differential PCR, PCR-SSCP, and methylation-specific PCR, respectively. Promoter hypermethylation was detected in 11 of 49 LMS cases (22%); homozygous deletion was detected in 3 of 49 cases (6%); and mutation was not recognized in any of the cases studied. Eight of 15 cases (53%) with decreased expression of p16 protein revealed methylation of the p16INK4a gene promoter. Promoter hypermethylation correlated closely with decreased expression and poor prognosis (p=0.0014 and p=0.0088, respectively). These results suggest that decreased expression of p16 protein can be considered as an independent reliable prognostic parameter in patients with soft tissue LMS. Furthermore, promoter methylation was more frequent than either homozygous deletion or mutation in this tumour, and promoter methylation was also shown to have a strong association with inactivation of the p16INK4a gene.  相似文献   
64.
Human endometrial carcinomas, as well as complex atypical hyperplasias (CAH), are estrogen related and frequently have mutations in the PTEN gene. However, the mutual contribution of estrogen and PTEN mutations to endometrial carcinogenesis in vivo is unknown. To address this issue, we investigated whether neonatal estrogenic treatments augment the incidence of CAH and carcinomas in murine PTEN (mPTEN) heterozygous (+/-) mutant mice, an animal model for endometrial carcinoma. Low doses of diethylstilbestrol (1 ng/g/day), genistein (50 microg/g/day) in phytoestrogens, estriol (E(3)) (4 microg/g/day), and vehicle (ethanol and corn oil) were administered subcutaneously daily to neonatal pups from the 1st to 5th day after birth. At 52 weeks of age, the morphological changes in the endometrium, and uterine expression of Hoxa 10 and Hoxa 11, were evaluated. These Hoxa genes are abdominal B-type homeobox genes, which normally regulate differentiation of the Müllerian duct. The incidence of CAH and adenocarcinomas of the endometrium was significantly decreased by the neonatal estrogenic treatments in the mPTEN+/- mice. Coincidentally, all treatments significantly decreased the stromal cell density, and CAH and adenocarcinomas rarely developed in the epithelium adjacent to the affected endometrial stroma. Moreover, the uterine expression of Hoxa 10 in mice with neonatal genistein and E(3) treatments, and that of Hoxa 11 in mice with all treatments, was significantly lower when compared with vehicle alone. Taken together, neonatal estrogenic exposure induced stromal atrophy and/or hyalinization accompanied by repressed expression of Hoxa 10 and Hoxa 11, and exerted an inhibitory effect on PTEN-related tumorigenesis. These findings provide new insight into the interaction between endometrial epithelium and stroma in endometrial carcinogenesis in vivo.  相似文献   
65.
We report here a 76-year-old male that presented with an immediate allergy to Anisakis following saury intake. Three and a half hours after eating pressed saury sushi, whole-body pomphus appeared including itching, facial dropsical swelling, and dyspnea. Diagnostic tests revealed specific IgE antibodies against anisakis simplex and a skin prick test was positive using an extraction of anisakis simplex. The results of skin prick tests using the body and internal organs of a saury were negative. Based on these results, we diagnosed the case as immediate allergy to Anisakis. Anisakis is parasitic to a diverse array of fish, and it seems rare that eating saury will induce an allergic response because the reported parasitic rate of Anisakis on saury is only 5%. In addition, as tropomyosin is currently considered to be the primary cause of allergies to Anisakis, renewed attention should be paid to other foods for which tropomyosin is also assumed to be a common antigen.  相似文献   
66.
Although poly(I:C) and LPS induced differential dendritic cell (DC) cytokine profiles and toll-like receptor (TLR) expression, all were capable of causing phenotypic and functional DC maturation. Both LPS and poly(I:C) downregulated TLR-4/MD-2 expression on DCs. Although poly(I:C) highly upregulated their cell surface TLR-9 expression, LPS upregulated the intracellular TLR-9 expression. LPS-treated DCs could not produce IL-12p70 in response to subsequent both LPS- and CpG DNA-stimulation. On the other hand, poly(I:C)-treated DCs retained to produce IL-12p70 by subsequent CpG DNA-stimulation, while subsequent LPS-stimulation did not induce IL-12p70 production. Chloroquine, inhibitor of endosomal maturation, completely inhibited cytokine production of LPS-treated DCs as well as unstimulated control in response to subsequent CpG DNA-stimulation, while it failed to delete the IL-12p40 and IL-10 production in poly(I:C)-treated DCs. These data suggest that poly(I:C) may induce a novel DC phenotype that preserves the capacity of cytokine production to subsequent CpG DNA-stimulation.  相似文献   
67.
Metanephric adenoma is the most commonly occurring member of the metanephric tumor family, which also includes metanephric adenofibroma and metanephric stromal tumor. According to the World Health Organization classification, however, it is not commonly multifocal. Reported herein is the case of a 9-year-old boy with multifocal metanephric adenoma. Histologically, surgical sections showed multifocal proliferation of small rounded and uniform cells with smooth nuclear contours, scant pale-staining cytoplasm, dark-staining nuclei, and inconspicuous nucleoli: the cells were arranged in sheets and acinal, ductal, glomeruloid, and papillary structures. On immunohistochemistry the tumor cells were positive for vimentin, cytokeratins (CAM5.2, AE1/AE3, and CK18), and WT1, but negative for cytokeratin 7 (CK7) and epithelial membrane antigen (EMA). The Ki-67 labeling index was <1%. In addition, cytogenetic analysis indicated a normal karyotype (46XY). Other histologically similar tumors are papillary renal cell carcinoma and nephroblastoma, and it is necessary to distinguish metanephric adenoma from those tumors because of malignancy. In contrast to those tumors, metanephric adenoma has inconspicuous nucleoli, loss of CK7 and EMA expression, and no mitotic figures. Thus, the histological and immunohistochemical features of the present case were compatible with metanephric adenoma.  相似文献   
68.
Tumor-associated macrophages (TAM) are known to possess the immunosuppressive M2 macrophage phenotype. They contribute to tumor growth, invasion, and metastasis by producing various mediators. Macrophages, especially M2 polarized macrophages, preferentially express CD163 and CD204, but few studies have investigated macrophage phenotypes in human ovarian tumors. The purpose of the present study was therefore to present results on macrophage differentiation in human ovarian serous and mucinous epithelial tumors. The method focused on immunostaining of paraffin-embedded tumor samples. Almost all macrophages infiltrating tumor tissues expressed CD163 and CD204, indicating the phenotypic shift toward M2 macrophage. The numbers of CD68-positive macrophages as well as of CD163- and CD204-positive macrophages in borderline and malignant tumors were significantly higher than in benign tumors. They correlated well with histological gradient of malignancy. Macrophage colony-stimulating factor (also known as colony-stimulating factor; CSF-1), which is one of the cytokines considered to induce TAM to polarize toward an M2 phenotype, was then evaluated. CSF-1 expression in malignant tumor cells was significantly higher than that in benign tumor cells and correlated with histological malignancy. These results suggest that CSF-1 derived from tumor tissues induces macrophages to shift toward the M2 phenotype, which is considered to promote tumor growth.  相似文献   
69.
Solitary fibrous tumor is a spindle cell neoplasm rarely arising in the thyroid gland. We present a 78-year-old man with the diagnosis of solitary fibrous tumor of the thyroid gland resected by subtotal thyroidectomy. Fine needle aspiration cytology via ultrasound guidance demonstrated a hypocellular aspirate that revealed follicular epithelial cells with mild nuclear atypia and scattered spindle cells with bland nuclei. Histologically, the patternless proliferation of spindle cells was seen among collagenous bundles, accompanied by hemangiopericytomatous vessels, and variously dilated follicles with mild atypical cells having slightly enlarged nuclei, indicating adenomatous goiter. The neoplastic spindle cells showed diffuse immunoreactivity to CD34, bcl-2, CD99 and vimentin, but were negative for cytokeratins, calcitonin, TTF-1 and CD5. Although solitary fibrous tumor arising in thyroid gland is rare, this tumor should be included in the differential diagnosis of thyroid spindle cell tumors and also that of adenomatous.  相似文献   
70.
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