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51.
Nonalcoholic fatty liver disease (NAFLD) is one of the most frequent causes of abnormal liver dysfunction, and its prevalence has markedly increased; however, the mechanisms involved in the pathogenesis of NAFLD have not been thoroughly investigated in humans. In this study, we evaluated the expression of fatty acid metabolism-related genes in NAFLD. Real-time RT-PCR was performed using liver biopsy samples from 12 NAFLD patients. The target genes studied were: acetyl-CoA carboxylase (ACC) 1, ACC2, and fatty acid synthase (FAS) for the evaluation of de novo fatty acid synthesis; carnitine palmitoyltransferase 1a (CPT1a), long-chain acyl-CoA dehydrogenase (LCAD), and long-chain L-3-hydroxyacyl-coenzyme A dehydrogenase alpha (HADHalpha) for beta-oxidation in the mitochondria; peroxisome proliferator-activated receptor- (PPAR-) alpha and cytochrome P450 2E1 (CYP2E1) for oxidation in peroxisomes and microsomes (endoplasmic reticulum) respectively; and diacylglycerol O-acyltransferase 1 (DGAT1), PPAR-gamma, and hormone sensitive lipase (HSL) for triglyceride synthesis and catalysis. In NAFLD, expression of ACC1 and ACC2, but not FAS was increased, indicating that de novo fatty acid synthesis is enhanced in NAFLD. In contrast, expression of CTP1a, a rate-limiting enzyme, was remarkably decreased, indicating that beta-oxidation in the mitochondria was decreased, although the expression of LCAD and HADHalpha was increased. Expression of PPAR-alpha was increased, whereas that of CYP2E1 was reduced. The expression of DGAT1, PPAR-gamma, and HSL was enhanced. These data suggest that in NAFLD, increased de novo synthesis and decreased beta-oxidation in the mitochondria lead to accumulation of fatty acids in hepatocytes, although the extent of oxidation in peroxisomes and microsomes remains unclear.  相似文献   
52.
Invasive fungal infection (IFI) is a significant complication after allogeneic hematopoietic stem cell transplantation (HSCT); however, we have little information on its clinical features after reduced intensity cord blood transplantation (RICBT) for adults. We reviewed medical records of 128 patients who underwent RICBT at Toranomon Hospital between March 2002 and November 2005. Most of the patients received purine-analogbased preparative regimens. Graft-versus-host disease (GVHD) prophylaxis was a continuous infusion of either tacrolimus 0.03 mg/kg or cyclosporine 3 mg/kg. IFI was diagnosed according to the established EORTC/NIH-MSG criteria. IFI was diagnosed in 14 patients. Thirteen of the 14 had probable invasive pulmonary aspergillosis and the other had fungemia resulting from Trichosporon spp. Median onset of IFI was day 20 (range: 1-82), and no patients developed IFI after day 100. Three-year cumulative incidence of IA was 10.2%. Four of the 13 patients with invasive aspergillosis (IA) developed grade II-IV acute GVHD, and their IA was diagnosed before the onset of acute GVHD. The mortality rate of IFI was 86%. Multivariate analysis revealed that the use of prednisolone >0.2 mg/kg (relative risk 7.97, 95% confidence interval 2.24-28.4, P = .0014) was a significant risk factor for IA. This study suggests that IFI is an important cause of deaths after RICBT, and effective strategies are warranted to prevent IFI.  相似文献   
53.
We analyzed DNA from 63 Japanese men with either azoospermiaor severe oligospermia whose Y chromosomes were cytogeneticallynormal. A total of 16 loci were examined: 15 loci on the longarm between DYS7E and DYZ1, and the YRRM1 locus, a candidategene for the azoospermic factor, AZF. One patient with a perlcentricinversion of the Y chromosome was also included. We detectedmicro-deletions in ten individuals. The YRRM1 gene was Involvedin only three of them. The remaining seven patients showed deletionbetween DYS7C and DYS239 in common, indicating the presenceof at least one additional gene, deletion of which causes azoospermia.  相似文献   
54.
Tumor necrosis factor alpha (TNFα) in activated monocytes exerts cytotoxic activity and has a variety of other biological effects. We isolated a polymorphic dinucleotide (CA) repeat sequence from a genomic clone containing the gene located at 6p21.3. High heterozygosity (0.80) makes this polymorphism a useful marker in the genetic study of disorders affecting immunological response and cell differentiation. Received: June 2, 1998 / Accepted: June 24, 1998  相似文献   
55.
The present paper deals with immunohistochemical and ultrastructural study of the lymph nodes of sinus histiocytosis with massive lymphadenopathy (Rosai and Dorfman, SHML) of a 12-year-old Japanese boy. This is the fourth case in Japan. Osseous manifestation was also found in the bilateral ulnae. With hallmarks of S-100 protein and interdigitating cytoplasmic extensions, the phagocytizing histiocytes proliferating in the sinuses were considered to be derived mostly from interdigitating cells in the paracortex or T cell dependent area, which have heretofore been regarded as nonphagocytizing. Furthermore, it is most interesting that lymphoid cells bearing thymic cortical cell-antigen (OKT 6) were increasingly recognized in the patient's peripheral blood. These results suggested that SHML is a specialized reactive histiocytosis analogous to histiocytosis X and histiocytic medullary reticulosis.  相似文献   
56.
Cadherin-17 (CDH17), also called liver–intestine cadherin, is a structurally unique member of the cadherin superfamily. Our serial analysis of gene expression demonstrated that CDH17 was one of the most up-regulated genes in advanced gastric carcinomas. CDH17 expression is known to be regulated by Cdx2. In the present study, we examined the expression of CDH17 in primary gastric carcinoma tissues by immunohistochemistry, and analyzed the correlation of CDH17 expression with clinicopathological characteristics and patients prognosis. CDH17 expression was detected in 63/94 (67%) of gastric adenocarcinomas in addition to intestinal metaplasia. The expression of CDH17 tended to be associated with intestinal type carcinoma, and carcinomas with CDH17 expression was significantly more frequent in advanced stage cases (80%) than in early stage (53%). The prognosis of patients with positive CDH17 expression was significantly poorer than that of the negative cases (P=0.0314). However, multivariate analysis revealed that CDH17 was not an independent prognostic factor. Six of seven cases that showed positive expression of Cdx2 simultaneously expressed CDH17 protein. These results suggested that the expression of CDH17 was characteristic of the advanced gastric carcinoma that is associated with poor prognosis.  相似文献   
57.
The purpose of the present study was to investigate the effects of informational and motivational level of feedback stimuli on the stimulus-preceding negativity (SPN). In the time estimation task, in which a visual stimulus was presented 3 s after a voluntary movement, (a) the information level (high information and low information) and (b) the motivation level (reward and no-reward) for feedback stimuli were manipulated. Under the high-information condition, subjects received feedback information about (1) correctness (correct or incorrect), (2) direction of error (under- or overestimate), and (3) degree of accuracy (accurate or less accurate) of their time estimation. In the low-information condition, however, they received information about the correctness only. In the reward condition, they received a monetary reward for accurate time estimations but received nothing in the no-reward condition. The results demonstrated a significant interaction of information by motivation level, showing that the SPN amplitude under the reward/high-information was larger than that in the no-reward/high-information condition. The results are discussed in terms of emotional anticipation, taking into consideration the result of self-report that subjects felt to be more motivated when they received precise information.  相似文献   
58.
Isolated rat Kupffer cells produced a factor which stimulated the synthesis of 2-macroglobulin (2M) in primary cultured rat hepatocytes. Although Kupffer cells placed in culture produced the factor without stimulation by lipopolysaccharide (LPS), the LPS-stimulated cells produced larger amounts of the factor. On the other hand, the production of the factor was inhibited by addition of actinomycin D. The induction of2M synthesis by cultured hepatocytes was enhanced in the presence of dexamethasone (Dex), in that hepatic synthesis of2M increased by addition of the factor alone and with Dex 1.5 and three- to four-fold, respectively. The factor was nondialyzable and stable at 60°C for 30 min. When the factor was fractionated using the molecular sieve method, the activity recovered in the fraction had a molecular weight of over 30,000.  相似文献   
59.
An autopsy case of systemic histiocytosis with excessive deposition of kappa-type light chain crystals was reported in a 58 year-old man who had consistently showed kappa-type light chain paraproteinemia, Bence Jones proteinuria and hypogammaglobulinemia for about 10 years until his death. However, no bony destruction was found by repeated X-ray examinations. At autopsy, extensive hyperplasia of crystal-storing histiocytes was observed in the bone marrow, spleen, liver, lymph nodes, interstitial tissues of visceral organs and loose connective tissues. In the bone marrow and some other tissues, mild proliferation of plasmocytoid cells containing small crystals were found. Histochemically the crystals positively stained with various methods for amino acids and proteins, especially with Weigerts' method for fibrin. Ultrastructurally intralysosomal crystal deposition was confirmed in the storage histiocytes and derivation of the crystals from Golgi's sacculi in the plasmocytoid cells was suggested. Biochemically the crystals were regarded as mainly consisting of dimers of a variable half of light chain immunoglobulin and immunochemically and immunohistochemically reacted to anti-kappa type light chain serum. Such a generalized storage histiocytosis may be secondarily induced by immunoglobulin synthesized in plasmocytoid cells.  相似文献   
60.
Carbohydrate expression of cancer cells is closely related to the metastatic nature of colorectal cancer. In the present study we investigated the relevance of carbohydrate expression profiles of colorectal cancer cells in the primary lesion to metastatic distribution patterns as well as prognosis in 134 cases. Carbohydrate expression was estimated by histochemistry with 17 kinds of lectins and 3 kinds of Lewis-related monoclonal antibodies (MAbs), and correlations between the staining and clinicopathological parameters were examined. The results showed that lymphatic invasion, lymph node metastasis, and peritoneal metastasis correlated with staining with lectins that bind galactose/N-acetylgalactosamine residues (Gal/GalNAc) such as Maclura pomifera (MPA), Arachis hypogaea (PNA), Helix pomatia (HPA), and Vicia villosa (VVA). In contrast, hepatic metastasis correlated with staining with Anguilla anguilla lectin (AAA), anti-LewisX (LEX-2), anti-sialyl Lewisa (NS19-9), and anti-sialyl-dimeric LewisX (FH-6) MAbs, all of which bind preferentially to fucosylated carbohydrate chains. The five-year survival rate of patients was related to the staining of cancers with MPA, HPA, FH-6 or NS19-9, and MPA- and FH-6 staining were independent prognostic factors. We conclude that carbohydrate expression profiles of cancer cells are relevant to the route of tumor cell dissemination, metastatic pattern as well as prognosis of colorectal cancer.  相似文献   
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