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Primary and recurrent cytomegalovirus (CMV) infections frequently cause CMV colitis in immunocompromised as well as inflammatory bowel disease (IBD) patients. Additionally, colitis occasionally occurs upon primary CMV infection in patients who are apparently immunocompetent. In both cases, the underlying pathophysiologic mechanisms are largely elusive - in part due to the lack of adequate access to specimens. We employed the mouse cytomegalovirus (MCMV) model to assess the association between CMV and colitis. During acute primary MCMV infection of immunocompetent mice, the gut microbial composition was affected as manifested by an altered ratio of the Firmicutes to Bacteroidetes phyla. Interestingly, these microbial changes coincided with high-titer MCMV replication in the colon, crypt hyperplasia, increased colonic pro-inflammatory cytokine levels, and a transient increase in the expression of the antimicrobial protein Regenerating islet-derived protein 3 gamma (Reg3γ). Further analyses revealed that murine and human intestinal epithelial cell lines, as well as primary intestinal crypt cells and organoids represent direct targets of CMV infection causing increased cell death. Accordingly, in vivo MCMV infection disrupted the intestinal epithelial barrier and increased apoptosis of intestinal epithelial cells. In summary, our data show that CMV transiently induces colitis in immunocompetent hosts by altering the intestinal homeostasis.  相似文献   
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Rheumatoid arthritis (RA) is an inflammatory disease typically affecting the joints, but the systemic inflammatory process may involve other tissues and organs. Many extra-articular manifestations are recognized, which are related to worse long outcomes. Rheumatoid nodules are the most common extra-articular feature, found in about 30% of patients. Secondary Sjögren's syndrome and pulmonary manifestations are observed in almost 10% of patients, also in the early disease. Active RA with high disease activity has been associated with an increased risk of such features. Male gender, smoking habit, severe joint disease, worse function, high pro-inflammatory markers levels, high titer of rheumatoid factor, and HLA-related shared epitope have been reported as clinical predictors of occurrence of these rheumatoid complications. In addition, there is a little evidence deriving from randomized controlled trials in this field, thus the therapeutic strategy is mainly empiric and based on small case series and retrospective studies. However, considering that these extra-articular manifestations are usually related to the more active and severe RA, an aggressive therapeutic strategy is usually employed in view of the poor outcomes of these patients.The extra-articular features of RA remain, despite the improvement of joint damage, a major diagnostic and therapeutic challenge, since these are associated with a poor prognosis and need to be early recognized and promptly managed.  相似文献   
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The novel bis-chelating carbacylamidophosphate type ligand, tetramethyl[pyridine-2,6-diyldi(iminocarbonyl)]diamidophosphate (H2L), and its sodium salt, NaHL, have been synthesized and their structural properties have been investigated. Coordination compounds of lanthanides [Ln(HL)2NO3]·i-PrOH (Ln = Eu3+, Tb3+) were obtained for the first time, isolated in the individual state and characterized by means of IR and NMR spectroscopies, electrospray ionization mass spectrometry (ESI-MS), potentiometric titration, and elemental, thermal gravimetric and X-ray diffraction analyses. It was shown that H2L behaves like a scorpionate type ligand and in a mono-deprotonated form coordinates in a tridentate manner via the oxygen atoms of phosphoryl and carbonyl groups with formation of a mononuclear metal complex. The protonation constants of H2L and stability constants of Eu3+ and Tb3+ complexes have been determined. According to the results of X-ray diffraction analysis the H2L and [Ln(HL)2NO3]·i-PrOH molecules have monomeric structure but NaHL is a dimer. The Hirshfeld surface and fingerprint plots of the compounds have been used to analyze various hydrogen bonds and intermolecular interactions displayed in the crystal structure.

A new bis-chelating scorpionate type CAPh ligand and its lanthanide complexes in solid state and solution.  相似文献   
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The term “trabecular myopathy” has been used to designate a syndrome resembling limb‐girdle muscular dystrophy in which the predominant pathological feature is an abundance of lobulated or trabecular muscle fibers. However, the validity of this nosological entity has not been verified. Herein we describe a 63‐year‐old man with a severe, progressive myopathy who exhibited the typical pathological features of both trabecular myopathy and nemaline myopathy in association with a biclonal gammopathy. In this case, adult‐onset nemaline myopathy was probably the primary disease process. The diagnostic significance of trabecular muscle fibers remains uncertain. Muscle Nerve, 2008  相似文献   
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The omentum, an important peritoneal tissue, is studded with a high number of immune aggregates, or “milky spots,” the number, function, and phenotype of which is largely unknown. We have analyzed the immune composition on the normal omentum and also have shown that both free immune cells and tumor cells in the peritoneal fluid bind preferentially to these immune aggregates. This binding may be mediated by the network of collagen I fibers, which overlay these areas. In addition, we have shown that not only do omental vessels express vascular endothelial growth factor receptor 3 (VEGFR3), a receptor that is only found on angiogenic blood vessels, but that tumor cells co-localize with these vessels, possibly increasing the ability of tumor to induce neovascularization and therefore thrive.  相似文献   
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Vascular smooth muscle cell (VSMC) proliferation is pivotal in the progression of hypertension, atherosclerosis, and restenosis. Resveratrol is a grape polyphenol that is implicated as an important contributor to red wine's vascular protective effects. Its antimitogenic action on VSMC is attributed to an array of pleiotropic effects, including modulation of the estrogen receptor (ER). To elucidate the mechanisms underlying resveratrol-mediated ER modulation and its inhibition of VSMC proliferation, we treated VSMC with resveratrol with or without the ER antagonist ICI 182,780 and measured cell proliferation and nitric oxide (NO) production. Resveratrol dose-dependently decreased VSMC DNA synthesis, with a half maximal inhibitory concentration (IC50) of 3.73+/-0.57 microM, and dramatically slowed cell growth, but did not induce VSMC apoptosis. Resveratrol-mediated decrease in proliferation was reversed by cotreatment with ICI 182,780, and resveratrol effectively competed with 17beta-estradiol for binding to the ER, exhibiting an IC50 of 8.92+/-0.14 microM. Resveratrol induced a sustained increase in ER-dependent NO production. Further, resveratrol-mediated decrease in VSMC proliferation was blunted by cotreatment with the general nitric oxide synthase (NOS) inhibitor N5-(1-Iminomethyl)-L-ornithine, dihydrochloride or with the inducible NOS (iNOS)-selective inhibitor S,S'-1,4-phenylene-bis (1,2-ethanediyl)bis-isothiourea, dihydrobromide, but not with the neuronal NOS-selective inhibitor 7-nitroindazole. Though resveratrol did not alter iNOS protein levels, it dose-dependently increased levels of iNOS activity, of the iNOS cofactor tetrahydrobiopterin (BH4), and of guanosine triphosphate cyclohydrolase I protein, the rate-limiting enzyme in BH4 biosynthesis. In addition, all of these effects were abolished by cotreatment with ICI 182,780. Thus, the antimitogenic effects of resveratrol on VSMC may be mediated by an ER-induced increase in iNOS activity.  相似文献   
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Acetylcholine (ACh) and opioid receptor agonists trigger the preconditioned phenotype through sequential activation of the epidermal growth factor (EGF) receptor, phosphatidylinositol 3-kinase (PI3-K), Akt, and nitric oxide synthase (NOS), and opening of mitochondrial (mito) K(ATP) channels with the generation of reactive oxygen species (ROS). Although extracellular signal-regulated kinase (ERK) has recently been reported to be part of this pathway, its location has not been determined. To address this issue, we administered a 5-min pulse of ACh (550 microM) prior to 30 min of ischemia in isolated rabbit hearts. It reduced infarction from 30.4 +/- 2.2% of the risk zone in control hearts to 12.3 +/- 2.8% and co-administration of the MEK, and, therefore, downstream ERK inhibitor U0126 abolished protection (29.1 +/- 4.6% infarction) con.rming ERK's involvement. MitoK(ATP) opening was monitored in adult rabbit cardiomyocytes by measuring ROS production with MitoTracker Red. ROS production was increased by each of three G protein-coupled agonists: ACh (250 microM), bradykinin (BK) (500 nM), and the delta-opioid agonist DADLE (20 nM). Co-incubation with the MEK inhibitors U0126 (500 nM) or PD 98059 (10 microM) blocked the increased ROS production seen with all three agonists. Direct activation of its receptor by EGF increased ROS production and PD 98059 blocked that increase, thus placing ERK downstream of the EGF receptor. Desferoxamine (DFO) which opens mitoK(ATP) through direct activation of NOS also increased ROS. PD 98059 could not block DFO-induced ROS production, placing ERK upstream of NOS. In isolated hearts, ACh caused phosphorylation of both Akt and ERK. U0126 blocked phosphorylation of ERK but not of Akt. The PI3-K inhibitor wortmannin blocked both. Together these data indicate that ERK is located between Akt and NOS.  相似文献   
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