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排序方式: 共有652条查询结果,搜索用时 31 毫秒
1.
Hideaki Iwaki Kazuyoshi Johnin Susumu Kageyama Chul Jang Kim Takahiro Isono Tatsuhiro Yoshiki 《International journal of urology》2007,14(10):918-923
OBJECTIVES: Vesicoureteral reflux (VUR) is the most common congenital urinary tract anomaly. This disease can pose a major threat to the kidneys as twenty percent of patients with endstage renal disease are reported to have VUR. Although genetic studies for uroplakin III (UPIII) have been reported recently, no study has focused on UPIII gene expression in VUR patients. We describe here the up-regulation of UPIII mRNA in exfoliated urinary cells from primary VUR patients. METHODS: A real-time RT-PCR for UPIII mRNA was performed on exfoliated urothelial cells from 18 primary VUR and 38 control samples. UPIII mRNA copies were calculated for each sample. The statistical differences were assessed by the Mann-Whitney U test. Receiver operator characteristic curves were constructed for analysis of the diagnostic values. RESULTS: UPIII mRNA was found to be up-regulated to a greater extent in VUR than in control exfoliated urinary cells (mean +/- SE: 497.0 +/- 178.5 copies vs. 69.0 +/- 10.0 copies, respectively, P < 0.001). In evaluating the measurement of urinary UPIII mRNA as a screening test for VUR, the sensitivity was 77.8% and the specificity was 76.3% by the best diagnostic cutoff point. CONCLUSIONS: This is the first report demonstrating up-regulation of UPIII in mRNA levels in VUR patients. We submit that the quantitative measurement of urinary UPIII mRNA has a potential of developing into the first non-invasive screening test for VUR. 相似文献
2.
Motohisa Kato Shigetoyo Saji Katsuyuki Kunieda Tatsuhiro Yasue Kimitoshi Nishio Mitsuri Adachi 《Surgery today》1997,27(8):766-768
We experienced a case of mediastinal lipoma, which is considered to be a relatively rare disease. A 3-year-old girl was referred
to Gifu University hospital because of fever and an abnormal shadow on her chest X-ray. The chest X-ray clearly showed a well-delineated
tumor shadow which seemed to oppress the diaphragm and the right atrium in the right lower lung area. A computed tomogram
(CT) of the chest showed a homogeneous mass localized on the right diaphragm and adjoining the right anterior chest wall and
heart. The mass showed a fat density measuring about-100 HU. Magnetic resonance imaging (MRI) showed a high-intensity mass
which was almost the same level as the subcutaneous fat on both the T1-weighted and T2-weighted images. Thoracotomy was performed and a fatty tumor was found. It arose from the right side of the pericardium and
adjoined the diaphragm, the anterior chest wall, and the thymus. There was no adhesion between the tumor and the surrounding
organs. It was resected easily and its contents were yellowish and homogeneous. The patient made an uneventful recovery and
was discharged 10 days after the operation. Light microscopy showed a lipoma consisting of mature adipose tissue and no malignancy
was found. 相似文献
3.
Tsukasa Tsunoda Toshifumi Eto Takahito Tsurifune Shigeki Tokunaga Tatsuhiro Ishii Koichi Motojima Teiji Matsumoto Tohru Segawa Kazuhide Ura Hiroshi Fukui 《Pathology international》1991,41(10):763-770
A solid and cystic tumor (SCT) was located at the head of the pancreas in a 43-year-old Japanese male, and pancreatoduodenectomy was performed on the suspicion of papillary carcinoma or cystadenocarcinoma of the pancreas. The lesion, which measured 4.5 X 4.5 X 4.0 cm, was clearly demarcated by connective tissue. The cut surface showed solid grayish-white areas with central cystic degenerative changes. The solid areas consisted of small round cells proliferating in a small solid or a pseudopapillary pattern. The tumor cells partially invaded the surrounding normal pancreatic parenchyma. Immunohistochemical studies revealed positive staining for alpha-1-antitrypsin and neuron-specific enolase, but no staining for known pancreatic hormones. Moreover, ultrastructural studies showed the absence of zymogen granules and the presence of anullate lamellae and neurosecretory granules. On the basis of these findings, a diagnosis of SCT of the pancreas was established. In order to clarify the histogenesis and biological behavior of the tumor, it is necessary to accumulate and analyze similar cases, an endeavor which in turn will contribute to the successful management of this disease. Acta Pathol Jpn 41: 763-770, 1991. 相似文献
4.
HeLa cell invasiveness and O antigen of Shigella flexneri as separate and prerequisite attributes of virulence to evoke keratoconjunctivitis in guinea pigs. 总被引:9,自引:7,他引:9
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N Okamura T Nagai R Nakaya S Kondo M Murakami K Hisatsune 《Infection and immunity》1983,39(2):505-513
Many rough mutants selected from isogenic smooth virulent and avirulent strains of Shigella flexneri were examined for virulence, using tissue culture infection and Sereny tests. Many of the rough mutants isolated from a virulent smooth strain were capable of penetrating tissue culture cells but incapable of producing a positive Sereny test. In contrast, we could not obtain from smooth avirulent strains any rough mutants capable of penetrating HeLa cells. Chemical analysis of lipopolysaccharide of some representative rough strains showed several patterns of sugar composition with a range of from Ra to Re chemotypes. There was no correlation between HeLa cell invasiveness and chemotypes of lipopolysaccharides, thus indicating little significance of oligosaccharides of the rough core as well as O antigens in the ability of S. flexneri to penetrate HeLa cells. When these invasive rough strains were given O antigen genes from a smooth avirulent Shigella Hfr strain, most of the transconjugants that expressed O antigens regained the ability to evoke keratoconjunctivitis in guinea pigs. We also examined the chromosomal loci of HeLa cell invasion by transferring carbohydrate fermentation genes of Escherichia coli K-12 Hfr and found two chromosomal loci, the rha and lac-gal regions, which control the ability to penetrate HeLa cells. These results suggested that O antigens and ability to penetrate tissue culture cells are independent and prerequisite attributes of virulence in Shigella flexneri to evoke keratoconjunctivitis in guinea pigs. 相似文献
5.
Beta-catenin mutations are frequent in calcifying odontogenic cysts, but rare in ameloblastomas 总被引:2,自引:0,他引:2
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Sekine S Sato S Takata T Fukuda Y Ishida T Kishino M Shibata T Kanai Y Hirohashi S 《The American journal of pathology》2003,163(5):1707-1712
We have reported previously that alterations to beta-catenin occur frequently in adamantinomatous craniopharyngioma. Based on its histological resemblance to some odontogenic tumors, we suspected the presence of common genetic alterations among these tumors. To address this issue, 11 cases of calcifying odontogenic cyst (COC) and 20 cases of ameloblastoma were investigated for the presence of beta-catenin mutations and beta-catenin expression. Ten COCs were successfully analyzed by direct sequencing, and nine of them were found to harbor somatic beta-catenin mutations. Immunohistochemically, all of the COCs showed nuclear and cytoplasmic expression of beta-catenin with a heterogeneous pattern. No beta-catenin mutations were found in ameloblastomas, except for one case of the follicular type. All follicular ameloblastomas exhibited moderate nuclear and cytoplasmic accumulation of beta-catenin, in contrast to the predominantly membranous expression seen in the plexiform type. beta-Catenin mutation is considered to be a characteristic genetic feature of COC, and may play a critical role in its histogenesis. Although ameloblastoma closely resembles COC histologically, the two have genetically distinctive features. 相似文献
6.
Age-hardening mechanisms and related ordering behaviors of the experimental (AuCu)1−xZnx alloys with x0.2 were investigated for dental applications. The addition of Zn to equiatomic AuCu greatly increased the age-hardening rate and delayed overaging. It was suggested that the quenched-in excess vacancies were greatly related to the age-hardening rate in the AuCu–Zn pseudobinary alloys. In these alloys, the hardness became maximum during the very initial stage of ordering, and with the development of ordered phase, the hardness began to decrease. Transmission electron microscopy revealed that the age-hardening of AuCu–Zn pseudobinary alloys is caused by lattice distortion that occurred during the very early stage of atomic ordering. The addition of Zn to AuCu effectively increased the density of antiphase boundaries per unit volume of the AuCu II superstructure. This is suggested to be the main cause for the retardation of the overaging in the alloys containing Zn of 5 at% or more. This pronounced effect of Zn addition to AuCu alloy on its age-hardening characteristics may be advantageous for obtaining stable mechanical properties of dental casting gold alloys. 相似文献
7.
Shigeki Sekine Tadakazu Shimoda Satoshi Nimura Yukihiro Nakanishi Takayuki Akasu Hitoshi Katai Takuji Gotoda Tatsuhiro Shibata Michiie Sakamoto Setsuo Hirohashi 《Modern pathology》2004,17(11):1421-1426
We report a patient with familial adenomatous polyposis who developed high-grade dysplasia against a background of fundic gland polyposis. Two large high-grade dysplasia lesions were found in the gastric body, where numerous fundic gland polyps were present. In both lesions, the dysplastic epithelium covered non-neoplastic oxyntic glands that occasionally exhibit cystic changes. A genetic analysis for APC (adenomatous polyposis coli) revealed a somatic 50-bp deletion involving codons 1502-1517 and 2-bp deletion at codon 1465 in each lesion of high-grade dysplasia. In contrast, six of the 18 fundic gland polyps were found to harbor an identical mutation: 1-bp insertion at codon 1556. Both lesions of high-grade dysplasia and the fundic gland polyps were similarly located in the fundic gland area and were caused by the inactivation of APC; however, their mutation profiles of APC were different. These results imply that fundic gland polyps and high-grade dysplasia of the stomach have distinct preferences for APC genotypes in their development. 相似文献
8.
Local skin response in mice induced by a single intradermal injection of bacterial lipopolysaccharide and lipid A.
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Y Ishikawa T Kirikae M Hirata M Yoshida Y Haishima S Kondo K Hisatsune 《Infection and immunity》1991,59(6):1954-1960
Dermal inflammation and hemorrhagic necrosis induced by bacterial lipopolysaccharide (LPS) and lipid A were studied in mice. In ddY mice, a single intradermal injection of Salmonella typhimurium S-form LPS and lipid A into the abdominal dermis elicited an edematous change due to an increase in local vascular permeability 12 h postinjection, followed by hemorrhagic necrosis from 24 to 72 h. This skin reaction was also induced in a dose-dependent manner by S-form LPS, R-mutant LPS, and lipid A of S. typhimurium and Escherichia coli, but not by polysaccharide from Salmonella S-form LPS. The dermal inflammation-inducing activities of LPS and lipid A were roughly in the following order (from highest to lowest): Re-form LPS, Rc-form LPS and lipid A, Ra-form LPS, and S-form LPS. These results suggest that the lipid A portion of the LPS molecule is responsible for the skin reaction. In C3H/HeN mice, Re-form LPS and lipid A induced the same intensity of skin reaction as that in ddY mice. In C3H/HeJ mice, which have a low response to LPS, Re-LPS and lipid A did not induce any hemorrhagic response but showed a distinct edematous change. Although hemorrhagic necrosis and edematous changes could be explained by quantitative differences in skin lesions, the other possible explanation is that hemorrhagic necrosis and the increase in local vascular permeability are induced by different mechanisms, only one of which depends on the regulation of the lps gene. 相似文献
9.
Influence of Imidazole-Dipeptides on Cognitive Status and Preservation in Elders: A Narrative Review
The worldwide increase in the number of patients with dementia is becoming a growing problem, while Alzheimer’s disease (AD), a primary neurodegenerative disorder, accounts for more than 70% of all dementia cases. Research on the prevention or reduction of AD occurrence through food ingredients has been widely conducted. In particular, histidine-containing dipeptides, also known as imidazole dipeptides derived from meat, have received much attention. Imidazole dipeptides are abundant in meats such as poultry, fish, and pork. As evidenced by data from recent human intervention trials conducted worldwide, daily supplementation of carnosine and anserine, which are both imidazole dipeptides, can improve memory loss in the elderly and reduce the risk of developing AD. This article also summarizes the latest researches on the biochemical properties of imidazole dipeptides and their effects on animal models associated with age-related cognitive decline. In this review, we focus on the results of human intervention studies using supplements of poultry-derived imidazole dipeptides, including anserine and carnosine, affecting the preservation of cognitive function in the elderly, and discuss how imidazole dipeptides act in the brain to prevent age-related cognitive decline and the onset of dementia. 相似文献
10.
Phosphorylation-dependent interaction of the N-methyl-D-aspartate receptor epsilon 2 subunit with phosphatidylinositol 3-kinase 总被引:3,自引:0,他引:3
Hisatsune C Umemori H Mishina M Yamamoto T 《Genes to cells : devoted to molecular & cellular mechanisms》1999,4(11):657-666
BACKGROUND: The NMDA receptors (NMDARs) are ion channels through which Ca2+ influx triggers various intracellular responses. Tyrosine phosphorylation of NMDARs regulates NMDA channel activities, which may be important in neuronal plasticity. The biological significance of the tyrosine phosphorylation events, however, differs among NMDAR subunits: tyrosine phosphorylation of NMDARepsilon1 increases NMDA channel activities, but that of NMDARepsilon2 does not. Since signal transductions from various cell surface receptors are mediated by protein-protein interaction through phosphotyrosine and the Src homology 2 (SH2) domain, we examined the possibility that phosphotyrosines in NMDARepsilon2 contribute to the intracellular signalling events. RESULTS: We first show that Fyn is deeply involved in the phosphorylation of NMDARepsilon2 and second that a phosphotyrosine in NMDARepsilon2 interacts with the p85 regulatory subunit of phosphatidylinositol 3-kinase (PI3-kinase). Both the level of tyrosine phosphorylation on NMDARepsilon2 and the amounts of the p85 subunit (p85) bound to NMDARepsilon2 are decreased in Fyn-deficient mice. Moreover, we show that ischaemia stimulates the binding of p85 to phosphorylated NMDARepsilon2, suggesting a physiological role of the phosphotyrosine/SH2-based interaction between NMDARepsilon2 and p85 in the brain. CONCLUSIONS: The tyrosine phosphorylation event on NMDARs is important in not only the regulation of its channel activity but also intracellular signalling mediated through the interaction of the NMDAR with SH2 domain-containing molecules. 相似文献