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1.
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   
2.
Despite the importance of short-chain fatty acids (SCFA) in maintaining the ruminant physiology, the mechanism of SCFA absorption is still not fully studied. The goal of this study was to elucidate the possible involvement of monocarboxylate transporter 1 (MCT1) in the mechanism of SCFA transport in the caprine rumen, and to delineate the precise cellular localization and the level of MCT1 protein along the entire caprine gastrointestinal tract. RT-PCR revealed the presence of mRNA encoding for MCT1 in all regions of the caprine gastrointestinal tract. Quantitative Western blot analysis showed that the level of MCT1 protein was in the order of rumen ≥ reticulum > omasum > caecum > proximal colon > distal colon > abomasum > small intestine. Immunohistochemistry and immunofluorescence confocal analyses revealed widespread immunoreactive positivities for MCT1 in the caprine stomach and large intestine. Amongst the stratified squamous epithelial cells of the forestomach, MCT1 was predominantly expressed on the cell boundaries of the stratum basale and stratum spinosum. Double-immunofluorescence confocal laser-scanning microscopy confirmed the co-localization of MCT1 with its ancillary protein, CD147 in the caprine gastrointestinal tract. In vivo and in vitro functional studies, under the influence of the MCT1 inhibitors, p -chloromercuribenzoate (pCMB) and p -chloromercuribenzoic acid (pCMBA), demonstrated significant inhibitory effect on acetate and propionate transport in the rumen. This study provides evidence, for the first time in ruminants, that MCT1 has a direct role in the transepithelial transport and efflux of the SCFA across the stratum spinosum and stratum basale of the forestomach toward the blood side.  相似文献   
3.
Sleep timing is influenced by the circadian system. Morningness-eveningness (ME) preference in humans is affected by the free-running period, which is determined by circadian clock-relevant genes. In this study, we investigated association between the 3111T/C polymorphism in the 3'-flanking region of hClock (Homo sapiens Clock homolog) and ME preference in 421 Japanese subjects. The Horne-Ostberg ME questionnaire (MEQ) scores showed normal distribution, with mean score of 51.2 +/- 1.4 (range, 25-73), and scores were positively correlated with sleep onset time (r = 0.541, P < 0.001) and wake time (r = 0.513, P < 0.001). MEQ scores were significantly lower in subjects with 3111C/C (n = 12) than in subjects with 3111T/C (n = 106, P < 0.001) or 3111T/T (n = 303, P < 0.001), suggesting a stronger eveningness preference in 3111C/C homozygotes. This group also showed significantly delayed sleep onset (P < 0.001), shorter sleep time (P < 0.001), and greater daytime sleepiness (P < 0.001) in comparison to parameters in the subjects with the 3111T allele. There was no significant difference in any of these parameters between the 3111C/T and 3111T/T genotypes. The influence of the 3111T/C polymorphism on ME preferences in Caucasian populations remains controversial. The present findings in a Japanese population sample, which should have a relatively low risk of population stratification effects, suggest the significance of the association of the 3111C/C allele of hClock with evening preference.  相似文献   
4.
One hundred and forty four patients with chronic hepatitis B were tested to identify new mutations associated with hepatitis B e antigen (HBeAg) negativity, using a full genome sequence analysis. All the patients were Chinese and had hepatitis B virus infection of genotype C. Patients with none of the pre-core or core promoter mutations were significantly (P < 0.001) less common in the group with anti-HBe (13%) than in the group with HBeAg (56%). The complete nucleotide sequence was determined in four anti-HBe-positive patients who had neither pre-core nor core promoter mutations and in five HBeAg-positive patients who also had neither of these mutations (the groups were matched for age and sex). Six mutations were found to be significantly more common in the former group than in the latter: G529A (3/4 vs. 0/5), C934A (4/4 vs. 1/5), A1053G (4/4 vs. 1/5), G1915T/A (4/4 vs. 0/5), T2005C/A (4/4 vs. 0/5), and C3026T (3/4 vs. 0/5). Three of the six mutations were significantly more common in the four anti-HBe-positive patients who had neither pre-core nor core promoter mutations, compared to 11 HBeAg-positive patients who had pre-core and core promoter mutations, and also compared to 15 anti-HBe-positive patients who had pre-core and core promoter mutations, suggesting further the specificity of these mutations. Of the six mutations, two resulted in amino acid substitution in the polymerase protein, and one is located near the enhancer I region. The results suggest that the six newly discovered mutations are associated with HBeAg negativity.  相似文献   
5.
Liver cirrhosis is caused by a relative imbalance between synthesis and degradation of collagens. Arg-Gly-Asp (RGD) peptide is a major adhesive domain of several extracellular matrix (ECM) components, such as that involved in the binding of fibronectin to the alpha5beta1 integrin receptor. We previously reported that RGD peptide increased the expression of matrix metalloproteinase in hepatic stellate cells (HSCs) which play a major role in hepatic fibrosis. We evaluated whether RGD-peptides inhibit the progression of liver fibrosis in an animal model of carbon tetrachloride-induced hepatotoxicity. RGD peptide (GRGDS) (1 mg/kg body weight) was injected intraperitoneally (i.p.) 3 times a week for one month. The group treated with control peptide (GRGES) showed pathologically typical hepatic fibrosis, while the RGD-treated group showed minimal fibrotic changes. The liver contents of collagen and hydroxyproline in the RGD-treated group was significantly lower than that of the control group. Collagenase activity measured in liver homogenates was significantly higher in the treated group than in the control group. In an in vitro study using TWNT-4 cells derived from human HSCs, RGD peptide (100 mug/ml) reduced the expression of type I collagen and tissue inhibitor of matrix metalloproteinase-1, and increased that of matrix metalloproteinase-1. These results indicated that RGD peptides inhibited liver fibrosis associated with both decreased collagen production and increased collagenase acitivity, and suggested that RGD peptide might be useful for the therapy of hepatic fibrosis.  相似文献   
6.
7.
We classified ipsilateral breast tumor recurrences (IBTRs) based on strict pathological rules. Ninety‐six women who were surgically treated for IBTR were included. IBTRs were classified according to their origins and were distinguished based on strict pathological rules: relationship between the IBTR and the primary lumpectomy scar, surgical margin status of the primary cancer, and the presence of in situ lesions of IBTR. The prognosis of these subgroups were compared to that of new primary tumors (NP) in the narrow sense (NPn) that occurred far from the scar. Distant‐disease free survival of IBTR that occurred close to the scar with in situ lesions and a negative surgical margin of the primary cancer (NP occurred close to the scar, NPcs) was similar to that of NPn. In contrast, IBTR that occurred close to the scar without in situ lesions (true recurrence (TR) that arose from residual invasive carcinoma foci, TRinv) had significantly poorer prognosis than NPn. IBTR that occurred close to the scar with in situ lesions and a positive surgical margin of the primary cancer (TR arising from a residual in situ lesion, TRis) had more late recurrences than NPcs. Precise pathological examinations indicated four distinct IBTR subtypes with different characteristics.  相似文献   
8.
9.
AIM: To characterize the baseline profiles of patients aged 70 years and above with hepatocellular carcinoma (HCC). METHODS: A series of 127 consecutive patients with HCC were enrolled between 2000 and 2004, and none of them had been diagnosed as having HCC previously. Baseline profiles, including parameters of hepatic function such as serum transaminase and prothrombin time [PT (% activity)] were compared between patients aged ≥70 and <70 years. RESULTS: Patients ≥70 years old showed significantly lower levels of aspartate aminotransferase (P=0.04) and alanine aminotransferase (P= 0.01), and significantly higher PTs (P = 0.04) and platelet counts (P = 0.02). Concomitantly, among ≥70-year-old patients, HCC was more common in non-cirrhotics, whereas among patients <70 years old, HCC was more common in cirrhotics. There was no significant difference between the groups in the number or size of tumors. CONCLUSION: Older HCC patients showed less inflammation and better preservation of hepatic function, indicating that not only cirrhotic patients but also non-cirrhotic patients should be considered as a high-risk group among the elderly.  相似文献   
10.
Clinical Autonomic Research - Delayed orthostatic hypotension (DOH), a fall in blood pressure after a 3-min cutoff, is clinically meaningful. The aim of this study was to elucidate the clinical and...  相似文献   
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