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71.
The etiology of nocturia in 70 patients with benign prostatic hyperplasia (BPH) who had nocturia of two or more times were examined based on frequency volume charts (FVC). Nocturia was classified into four groups: nocturnal polyuria, low capacity, combined nocturia, and no evidence of abnormality. Nearly half of the cases had nocturnal polyuria only. A little under 70% of patients had associated nocturnal polyuria (nocturnal polyuria+combined nocturia). Naftopidil was administered for three months to the patients with BPH who had nocturia with a urinary frequency of two or more times. Clinical efficacy was evaluated in 32 patients based on FVC and naftopidil was shown to improve nocturia. The improvement in nocturia was determined by the increment in voided volume.  相似文献   
72.
Merkel cell carcinoma (MCC) is an aggressive neuroendocrine carcinoma of the skin. MCCs often show characteristic paranuclear dot-like immunopositivity for cytokeratin 20 (CK20), a globular aggregation of CK20 intermediate filaments. These aggregates typically form rhabdoid features and fibrous bodies and may be associated with a down-regulation in adhesion molecules (AMs). To date, the relationship between the expression of AMs and CK20 and clinicopathological findings in MCC has not been well examined. In this immunohistochemical study, we assessed the expression of AMs, CK20, and chromogranin A (CgA) on MCCs in 8 men and 23 women with this disease, and also characterized their clinicopathological features. This study is the largest of its kind that has been undertaken to date in Japanese patients. Compared to normal tissue, E-cadherin and α- and β-catenins showed reduced membranous expression in 95.7%, 46.7%, and 45.2% of MCCs, respectively. Nuclear E-cadherin localization was seen in four tumors, all of which predominantly showed a CK20 dot pattern. However, there was no significant relationship between the membranous expression of AMs and a CK20 dot pattern. E-cadherin expression was significantly lower in tumors of ≥2 cm, and tumors negative for E-cadherin more frequently developed outside of the head and neck than within those regions. CgA was more intensely expressed in tumors with uniform nuclei and a dense lymphocytic infiltrate than in those that showed pleomorphisms and that had few, if any, infiltrating lymphocytes. These findings suggest that MCCs have a reduced expression of AMs and that down-regulation of E-cadherin expression may correlate with increased tumor aggressiveness. The fact that no significant relationship was demonstrable between the membranous expression of AMs and the CK20 expression pattern suggests that the mechanism of aggregation of intermediate filaments may be different in different types of tumors.  相似文献   
73.
Female adnexal tumor of probable Wolffian origin (FATWO) is a rare entity which is believed to originate from mesonephric (Wolffian) remnants on the basis of its location where the remnants are abundant. Its behavior is usually indolent, although some cases can recur or metastasize. The authors present the clinicopathological features of two cases of FATWO arising in the broad ligament, and focus on the expression of adhesion molecules and proliferative marker. Mesonephric duct remnants are also examined in an attempt to elucidate the histogenesis of FATWOs. The two FATWOs were well-circumscribed solid masses arising in the leaves of the broad ligament and histological examination revealed a mixture of cysts and tubules imparting a sieve-like pattern and mucin-negative eosinophilic secretion within these tubules. Immunohistochemically, the tumors showed the expression of cytokeratin 7 and 20, high-molecular-weight cytokeratin, and calretinin, which closely resembled that of the mesonephric duct remnants. Regarding CK 20, CD 10, EMA, S-100 protein, and vimentin their expression was in part not identical with previous studies. E-cadherin, alpha and beta-catenin were strongly expressed along the cell membrane of the tumor cells. The Ki-67 labeling index of FATWO was 0% and 3.2% in each case. The preservation of the E-cadherin-catenin complex and low Ki-67 labeling index could explain the indolent behavior and low malignant potential of this tumor.  相似文献   
74.
PURPOSE: To screen for mutations in the MYOC gene in Japanese patients with primary open-angle glaucoma (POAG) using denaturing high-performance liquid chromatography (DHPLC). PATIENTS AND METHODS: Blood samples were collected from 171 patients with POAG and 100 controls from seven institutions in Japan. For high-throughput analysis, seven exonic regions were amplified by polymerase chain reaction using DNA pooled from three patients; each DNA pool was then analyzed chromatographically. For analysis of a small number of samples, 7 exonic regions were amplified separately but simultaneously with annealing at 58 degrees C in each patient and then chromatographed, using 7 wells of the same 96-well plate per sample. When chromatographic patterns were abnormal by either method, the PCR products of the individual samples were sequenced. RESULTS: Four glaucoma-causing mutations were identified in five POAG patients (2.9%). One missense mutation, Phe369Leu, is new; and three others, Ile360Asn, Ala363Thr, and Thr448Pro, have been reported in Japanese patients. Phe369Leu was associated with adult onset POAG. CONCLUSIONS: Mutations in the MYOC gene were demonstrated chromatographically in 2.9% of our Japanese POAG patients. The use of pooled DNAs with DHPLC analysis is a time- and labor-saving technique. All mutations detected appear to be specific to Japanese patients.  相似文献   
75.
Bone marrow cells of patients with myelodysplastic syndromes (MDS) frequently undergo apoptosis, though the apoptotic cell ratio decreases when overt leukemia (OL) develops. Thus, we compared the expression of the inhibitor of apoptosis protein (IAP) gene family proteins in bone marrow samples from control, MDS, OL transformed from MDS (MDS --> OL), and de novo acute myelogenous leukemia (AML) subjects by the quantitative real-time RT-PCR method and an immunohistochemical approach. Overexpression of mRNA for survivin, cIAP1, NAIP and XIAP was significant in MDS bone marrow cells compared with control samples. However, the expression of mRNA for survivin, cIAP1 and cIAP2 exhibited a remarkable decrease after the development of OL (MDS --> OL). By immunohistochemistry, survivin was found to localize to the nucleus of myeloid cells in the majority of MDS cases. Next, the chronological changes in the expression of IAPs were determined in cases of MDS with evolution of OL. Although the expression of cIAP1 and cIAP2 revealed a sudden or gradual decrease as OL developed, survivin in many cases and XIAP in the majority of cases exhibited a peak of expression before a decline, indicating that these IAPs could be associated with the early events in the development of OL.  相似文献   
76.
Survivin, a member of the inhibitor of apoptosis protein (IAP) gene family, has been detected widely in fetal tissue and in a variety of human malignancies. In the current study, we investigated the expression of IAP family proteins in bone marrow samples from acute lymphocytic leukemia (ALL), chronic lymphocytic leukemia (CLL) and control cases by quantitative real-time RT-PCR method and an immunohistochemical approach. Overexpression of survivin and cIAP2 mRNA was significant in CLL bone marrow cells (P < 0.05, respectively) compared with control samples. By immunohistochemistry, survivin was detected in a few scattered myeloid cells in all cases of control bone marrow. Concerning the ALL bone marrow, more than half the cases demonstrated positive expression of survivin (8 out of 13), while the majority of CLL cases (20 out of 21) exhibited intense expression of survivin. The differential subcellular localization of survivin was distinct between ALL and CLL cases. ALL cells essentially revealed nuclear localization of survivin as well as cytoplasmic signals in some cases, while CLL cells from the majority of cases predominantly showed cytoplasmic expression. Next, RT-PCR was performed for the expression of survivin and its splicing variant, survivin-2B and survivin-deltaEx3 in ALL and CLL cells, as the distribution of these variants would be regulated by nuclear/cytoplasmic transport system. In both ALL and CLL bone marrow samples, the expression of wild-type survivin was more predominant than that of survivin-2B or survivin-deltaEx3, although the expression of survivin-deltaEx3 was prominent in samples from survivin-expressing ALL cases. Thus, the splicing of survivin mRNA may be differently regulated in ALL and CLL cells, causing distinct manners of nuclear/cytoplasmic transport of survivin protein. In conclusion, our observations indicate a differential regulatory mechanism for the expression of IAP family proteins in ALL and CLL cells, although the functions of IAP families and the mechanisms of nuclear/cytoplasmic transport of survivin should be clarified in future studies.  相似文献   
77.
Carcinogenesis of the prostate involves androgen influences, and associations between genetic polymorphisms of androgen receptor and metabolizing enzymes and prostate cancer risk have been reported. Roles for non-androgenic hormones are not well defined, but they also may have an impact judging from epidemiological and animal experimental alphalambda zeta of data. The purpose of the study was to determine whether hormone-related polymorphisms are associated with prostate cancer risk. A case-control study was performed with 147 Japanese prostate cancer patients and 266 urological controls. Polymorphisms of target genes [cytochrome P450 (CYP) 1B1, Leu432Val; debrisoquine hydroxylase, (CYP2D6)*4; aromatase (CYP19), Arg264Cys; estrogen receptor (ER)alpha-Xx (Xba I) and Pp (Pvu II); ERbeta-Rr (Rsa I); progesterone receptor (PR) Alu in intron 7] were examined by PCR-based methods. The capital and small letters signify the absence and presence of restriction sites, respectively. Odds ratios (OR) were adjusted for age using multiple logistic regression analysis with SPSS Medical Pack. Among the seven examined genetic polymorphisms, significant associations between CYP1B1 Leu432Val (OR 4.80; 95% confidence interval (CI), 1.21-19.05) and Alu in intron 7 of PR (OR 4.17; 95%CI, 1.26-13.85) were found. As for combined effects, the CYP1B1 polymorphisms (Leu/Val+Val/Val) together with heterozygosity for Alu in the PR were more frequent among prostate cancer patients (1.45%) than controls (0.41%), although without significance (OR, 3.99; 95%CI, 0.36-44.8). The combination of ERalpha (P/p+p/p) polymorphisms with heterozygosity for Alu in the PR demonstrated an OR of 4.56 (95%CI, 1.01-20.6). This pilot study showed that CYP1B1 and PR polymorphisms, alone or in combination, might be associated with prostate cancer risk. They might, therefore, have potential as a tool for identifying high-risk individuals.  相似文献   
78.
The cribriform-morular variant (C-MV), an unusual and peculiar subtype of papillary thyroid carcinoma (PTC), has been observed frequently in familial adenomatous polyposis (FAP)-associated thyroid carcinoma and also in sporadic thyroid carcinoma. In this paper, five young women with the C-MV of PTC, aged 22-34 years at cancer diagnosis, are reported; two of them had attenuated FAP. Grossly, one FAP-associated tumour and one sporadic tumour were multicentric and the others were solitary. Histologically, the tumours were encapsulated and exhibited a combination of cribriform, follicular, trabecular, solid, and papillary patterns of growth, with morular areas. Immunohistochemically, the tumour cells showed cytoplasmic expression of thyroglobulin, neuron-specific enolase, epithelial membrane antigen, high- and low-molecular-weight cytokeratins, vimentin, and bcl-2 protein; nuclear expression of oestrogen and progesterone receptors, and retinoblastoma protein; and cytoplasmic and nuclear accumulation of beta-catenin. Germline mutations of the adenomatous polyposis coli (APC) gene were investigated using the protein truncation test in four subjects, including two FAP individuals. Germline APC mutation was identified in only one FAP patient with the multicentric C-MV of PTC, who had a thymidine deletion at codon 512, resulting in a frameshift leading to a premature stop codon. No loss of heterozygosity of loci close to the APC gene was detected in tumour tissues from these four patients. Somatic mutation analysis of exon 3 of the beta-catenin gene (CTNNB1) revealed alterations in seven tumours from all five individuals: one at a serine residue (codon 29), three at amino acids adjacent to serine or threonine residues (codons 22, 39, and 44), and three at other amino acids (codons 49, 54, and 56). Moreover, each of two different tumours examined from two patients with the multicentric C-MV of PTC, had different somatic mutations of the CTNNB1 gene. Taken together, these data suggest that accumulation of mutant beta-catenin contributes to the development of the C-MV of PTC.  相似文献   
79.
Radiation-induced-thymic lymphoma occurs in young,but not in old mice   总被引:1,自引:0,他引:1  
Young mice exposed to fractionated whole-body irradiation develop thymic lymphoma. By using young and old mice, we examined the effect of age on the occurrence of radiation-induced thymic lymphoma in mice. In the first experiment, young and old mice were grafted with newborn thymus under kidney capsule and then treated with fractionated whole-body irradiation (FWI). In the second and third experiments, four combinations of bone marrow chimeras were constructed by transplanting bone marrow cells from young and old mice into young and old mice. Then these chimera mice were grafted with newborn thymus and treated with fractionated whole-body irradiation. The results in the present study indicate that the incidence of thymic lymphoma is influenced by age factors of thymic microenvironment, bone marrow, and host environment. If they are all young, the incidence of thymic lymphoma is high. If one of these is old, the incidence definitely decreases. Thymic lymphoma never occurred in old thymic environment even in the presence of young thymocytes. In conclusion, age advantage is present in the induction of thymic lymphoma after the treatment with FWI and the incidence definitely decreases in the presence of old factors.  相似文献   
80.
Optically clear nuclei (OCN) have been observed in morules of some neoplasms and in some conditions unrelated to the development of the morules. We first report a case of ovarian borderline endometrioid tumor (BET) showing the morules associated with OCN. The patient was a 47-year-old premenopausal woman with a left ovarian cystic tumor, atypical endometrial hyperplasia, and elevated serum levels of FSH, LH, estradiol, and CA 125. The resected ovarian tumor measured 6 cm in diameter, and showed a papillary growth. Histologically, the ovarian tumor was consistent with BET, and the morules with OCN were scattered. Immunohistochemically, OCN were proven to be rich in biotin. An aberrant nuclear expression of beta-catenin was observed in both the tumor cells and the morular cells. Our case may suggest the possibility that the appearance of OCN with or without morules in ovarian tumors is related to endometrioid differentiation of the tumor cells, and should be recognized as a diagnostic clue of ovarian endometrioid tumors. Although female sex hormones have been reported to play a role in the occurrence of OCN, the participation of beta-catenin mutation has also been suggested.  相似文献   
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