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31.
Restenosis after coronary artery stent implantation is attributed chiefly to intimal hyperplasia, which is prevented experimentally by angiotensin-converting enzyme (ACE) inhibitors. Therefore, the present study investigated whether the effect of quinapril, a tissue-specific ACE inhibitor, on the prevention of coronary restenosis differs according to ACE polymorphism. One hundred consecutive patients with successful stent implantation were randomly assigned to quinapril and control groups. Both follow-up angiography and ACE polymorphism analysis were obtained from 92 patients (control, 46; quinapril treatment, 46). The prevalence of risk factors did not differ statistically according to quinapril treatment or ACE genotypes. There was no statistically significant difference in the occurrence of restenosis 6 months after stenting between the groups. Quantitative coronary angiography revealed that quinapril treatment resulted in significantly higher minimal lumen diameter and significantly lower percent diameter stenosis (22.9 +/- 22.6 vs 37.1 +/- 19.7% in the control group, p < 0.05) in patients with the D allele although there was no difference in those with the II genotype. In addition, intravascular ultrasound revealed that quinapril treatment significantly prevented the loss of minimal lumen cross-sectional area and the increase in percent area stenosis (34.5 +/- 14.0 vs 53.3 +/- 16.4% in the control group, p < 0.05) in patients with the D allele compared to those with the II genotype. These results suggest that the administration of ACE inhibitors for the attenuation of lumen loss after coronary stent implantation is best for subjects with the D allele of the ACE genotype.  相似文献   
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Effective therapies for alcohol-associated liver disease (ALD) are limited; therefore, the discovery of new therapeutic agents is greatly warranted. Toll-like receptor 7 (TLR7) is a pattern recognition receptor for single-stranded RNA, and its activation prevents liver fibrosis. We examined liver and intestinal damage in Tlr7−/− mice to determine the role of TLR7 in ALD pathogenesis. In an alcoholic hepatitis (AH) mouse model, hepatic steatosis, injury, and inflammation were induced by chronic binge ethanol feeding in mice, and Tlr7 deficiency exacerbated these effects. Because these results demonstrated that endogenous TLR7 signaling activation is protective in the AH mouse model, we hypothesized that TLR7 activation may be an effective therapeutic strategy for ALD. Therefore, we investigated the therapeutic effect of TLR7 agonistic agent, 1Z1, in the AH mouse model. Oral administration of 1Z1 was well tolerated and prevented intestinal barrier disruption and bacterial translocation, which thus suppressed ethanol-induced hepatic injury, steatosis, and inflammation. Furthermore, 1Z1 treatment up-regulated the expression of antimicrobial peptides, Reg3b and Reg3g, in the intestinal epithelium, which modulated the microbiome by decreasing and increasing the amount of Bacteroides and Lactobacillus, respectively. Additionally, 1Z1 up-regulated intestinal interleukin (IL)-22 expression. IL-22 deficiency abolished the protective effects of 1Z1 in ethanol-induced liver and intestinal damage, suggesting intestinal IL-22 as a crucial mediator for 1Z1-mediated protection in the AH mouse model. Collectively, our results indicate that TLR7 signaling exerts protective effects in the AH mouse model and that a TLR7 ligand, 1Z1, holds therapeutic potential for the treatment of AH.

Alcohol-associated liver disease (ALD) is caused by chronic and excessive consumption of alcohol. The disease ranges from alcohol-associated fatty liver to alcoholic hepatitis (AH), fibrosis, cirrhosis, and hepatocellular carcinoma (HCC) (1). Alcohol-associated fatty liver is considered reversible and nonprogressive. Nearly 35% of heavy alcohol drinkers develop AH, and up to 40% of severe AH patients die within 6 mo (2). AH patients who survive may progress to alcohol-associated cirrhosis. Treatment options for AH involve the use of corticosteroids and have remained largely unchanged since the early 1970s. Unfortunately, not all patients respond to corticosteroids, and the benefits are temporary in responders (1, 2). Early liver transplant has been shown to be superior to medical management for severe AH, but it still has limitations and can only be considered in a highly selective group of patients (1, 2). Thus, the identification of a better molecular therapeutic target for ALD is a significantly unmet medical need for the development of effective therapies for AH.Previous studies have demonstrated the involvement of Toll-like receptors (TLRs), including TLR2, TLR4, and TLR9, in the development of ALD (38). In addition to the direct effect of alcohol and its metabolite, acetaldehyde, in hepatocytes, ethanol intake affects the function of the intestinal epithelial barrier. Chronic alcohol consumption disrupts intestinal tight junction integrity and increases gut permeability, resulting in elevated bacterial lipopolysaccharide (LPS) concentrations in the portal and systemic circulation (4). Translocated LPS activates resident hepatic macrophages, known as Kupffer cells, via TLR4, thereby promoting ALD (1, 2, 7, 8). Other TLRs, such as TLR2 and TLR9, recognize gram-positive bacterial components and bacterial CpG-DNA, respectively (3, 4). Furthermore, TLR2, TLR9, and MyD88 are required for the development of the preclinical AH murine model (5), whereas TLR4 and TLR9 exert protective effects against intestinal inflammation (9, 10).TLR7 signaling has been shown to be protective against liver fibrosis in mice (11). Tlr7−/− mice exhibit augmented cholestasis and carbon tetrachloride (CCl4)-induced liver fibrosis (11). TLR7 signaling also induces IFN-α production in dendritic cells (DCs), followed by interleukin (IL)-1 receptor antagonist (IL-1Ra) induction in Kupffer cells. IL-1Ra suppresses IL-1-induced hepatic stellate cell (HSC) activation, resulting in inhibition of liver fibrosis (11). Among the TLRs, TLR3 and TLR7 activation has been reported to ameliorate some liver diseases (11, 12). However, a major disadvantage of the currently available synthetic ligands for TLR3 and TLR7, such as poly I:C, imiquimod, and R848, is the excessive induction of proinflammatory cytokines (3, 4). Thus, developing agents without undesirable adverse effects is of great clinical interest.IL-22 is a hepatoprotective cytokine produced by T helper (Th) 17 cells, Th22 cells, γδ T cells, natural killer (NK) T cells, and innate lymphoid cells (ILCs) (13). Exogenous administration of IL-22 has a profound effect on tissue repair following liver injury via the promotion of proliferation and inhibition of apoptosis in hepatocytes of mouse models of AH (14), liver fibrosis, and drug- and LPS-induced liver injury. Also, IL-22 promotes tissue repair in the intestines and is protective against intestinal epithelial damage and inflammation (13). These findings suggest that IL-22 may suppress ALD via the maintenance of intestinal barrier function, thereby preventing increased intestinal permeability and bacterial translocation due to intestine-derived microbial products that promote ethanol-induced liver injury (15, 16).Here, we have developed a synthetic TLR7 ligand, 1Z1, that possesses antiinflammatory effects via IL-22 induction and that is devoid of systemic toxicity after oral administration (1719). Treatment with 1Z1 has already been reported to be effective for allergic encephalomyelitis, arthritis, dextran sodium sulfate (DSS)-induced colitis, and type I diabetes in mice (1720). We hypothesize that targeting TLR7 activation may be an effective treatment strategy for ALD. Our experimental results demonstrate that 1Z1 oral administration inhibits ethanol-induced liver and intestinal damage and that these beneficial effects are due to intestinal IL-22 induction in an AH murine model.  相似文献   
33.
To examine the morphology of colitis and study the role of the immune system in colitis, we compared colitis in immunocompetent Wistar-Kyoto rats with that in spontaneously hypertensive rats, known to have T-cell dysfunction. Rats were treated with 3% dextran sulfate in drinking water for periods ranging from 3 to 60 days. Diarrhea developed earlier and was associated with a more severe weight loss in Wistar-Kyoto rats than spontaneously hypertensive rats. The morphologic findings (flattening of the gland epithelium, gland dropout and ulceration) in spontaneously hypertensive rats were milder than in Wistar-Kyoto rats. Only spontaneously hypertensive rats survived 60 days of treatment; the findings included ulceration, crypt distortion, and inflammatory pseudopolyp formation. Immunostaining for B-cell, T-cell, and macrophage markers showed no difference in the distribution of these cells in the mucosa of Wistar-Kyoto rats and spontaneously hypertensive rats. Spontaneously hypertensive rats with T-cell dysfunction develop dextran sulfate sodium-induced colitis.  相似文献   
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OBJECTIVE: Hyper-high density lipoprotein (HDL)-cholesterolemia has been considered to be anti-atherogenic and is referred to as longevity syndrome. However, hyper-HDL-cholesterolemia induced by a cholesteryl ester transfer protein (CETP) deficiency may not be athero-protective, rather being atherogenic in nature. In a rural area in central Japan, the incidence of hyper-HDL-cholesterolemia has been found to be rather high (3.1% of healthy people). We studied healthy Japanese people in this area with hyper-HDL-cholesterolemia, particularly in relation to CETP. METHODS: Serum lipids were analyzed, and CETP mass was determined with an enzyme immunoassay method. MATERIALS: Blood was drawn after an overnight fast from 17 Japanese (5 males and 12 females) with serum HDL-cholesterol (C) > or =100 mg/dl. RESULTS: Serum CETP mass in hyper-HDL-cholesterolemic subjects was distributed in a wide range. Serum CETP mass was positively correlated with low-density lipoprotein (LDL)-C, apolipoprotein (Apo) B, and LDL-C/HDL-C, with statistical significance. CETP was also positively correlated with LDL-C/Apo B. CONCLUSION: These results suggest that hyper-HDL-cholesterolemia may not be a single clinical entity, but a mixture of various pathophysiological conditions, and that the ratio of LDL-C to HDL-C and the size of LDL may be important factors in classifying these conditions.  相似文献   
40.
To identify CTL-directed antigens in gastrointestinal cancer, we have investigated antigens recognized by the HLA-A2-restricted CTL line established from T cells infiltrating into colon cancer and report herein cleavage and polyadenylation specificity factor (CPSF) as a potent antigen holding peptides capable of inducing CTLs. Five peptides at amino acid positions 250-258, 392-400, 534-542, 1296-1304 and 1359-1368 of CPSF, which were recognized by the CTL line, were found to have the ability to induce HLA-A2-restricted and tumor-specific CTLs in peripheral blood mononuclear cells of the majority (69%, 11/16) of gastrointestinal cancer patients with different HLA-A2 subtypes. Thus, these peptides might be appropriate molecules for use in the peptide-based specific immunotherapy of HLA-A2(+) patients with gastrointestinal cancers.  相似文献   
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