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Although pulmonary arteriovenous malformations (PAVM) are relatively rare in children, they are important in the differential diagnosis of common pulmonary problems, such as hypoxemia, hemoptysis and dyspnea on exertion. We report the cases of two PAVM patients with different presentations and describe the treatment strategies.  相似文献   
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Luteinizing hormone (LH) consists of alpha- and beta-subunits, and synthesis and secretion of LH are regulated by gonadotropin-releasing hormone (GnRH). In order to examine the molecular mechanisms by which GnRH regulates LH secretion, we transfected alphaT3-1 cells with rat LHbeta-subunit cDNA under the control of a constitutive promoter and established a stable cell line of LH2 cells which secreted LH in response to GnRH. Pulsatile and continuous GnRH pretreatments increased gene expression of the alpha-subunit and synthesis of LH, and enhanced the LH secretion by brief treatments with GnRH and 56 mM KCl. The LH secretions were partially blocked by elimination of extracellular Ca2+. GnRH-induced LH secretion was completely inhibited by calphostin C (a protein kinase C inhibitor) and 1 microM wortmannin. In contrast to the GnRH induction, high K+-induced LH secretion was inhibited by KN93, a Ca2+/calmodulin-dependent protein kinase II inhibitor, as well as by 1 microM wortmannin. We also confirmed that activation of cAMP-pathway induced LH secretion, but activation of mitogen-activated protein (MAP) kinase pathway was not involved in LH secretion. These results suggest that GnRH directly regulates LH secretion as well as LHbeta-subunit synthesis, and that LH2 cells are a useful model for the study of LH secretion induced by several secretagogues.  相似文献   
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Background and methodsThere is controversy about the association between mild-to-moderate alcohol consumption and a reduced risk of cardiovascular diseases. The relationships between daily alcohol consumption and the incidence of acute myocardial infarction (MI) or ischemic stroke (IS) were examined in men in a community-based, prospective cohort study (n = 8014, age 40–80 years, mean age = 64.1 years). Alcohol consumption was categorized into 3 groups (A1, none or occasional; A2, ≤25 g/day; A3, >25 g/day as ethanol) at baseline.ResultsDuring the mean follow-up of 5.5 years, 53 MIs and 186 ISs occurred. On Cox regression analysis adjusted for age, hypertension, diabetes, dyslipidemia, smoking index, and body mass index (BMI), the hazard ratio (HR) for incident MI was significantly lower in the A2 group than in the A1 group (HR = 0.49, p = 0.043). The HR for incident MI in the A3 group tended to be lower than in the A1 group (HR = 0.53, p = 0.10). In obese subjects, while a significantly lower HR for incident MI in the A2 group was retained (HR = 0.29, p = 0.049), no significant difference in the HR of the A3 group compared with the A1 group was found. No significant differences were found in the IS-free curve among the 3 groups of alcohol consumption.ConclusionsAlcohol consumption may have a protective effect on the onset of MI but not on IS in the general population. A U-shaped relation between alcohol consumption and incident MI was found in obese subjects. An appropriate limit for daily alcohol consumption, depending on the risk of ischemic heart disease, may need to be established.  相似文献   
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Nuclear reprogramming enables patient-specific derivation of induced pluripotent stem (iPS) cells from adult tissue. Yet, iPS generation from patients with type 2 diabetes (T2D) has not been demonstrated. Here, we report reproducible iPS derivation of epidermal keratinocytes (HK) from elderly T2D patients. Transduced with human OCT4, SOX2, KLF4 and c-MYC stemness factors under serum-free and feeder-free conditions, reprogrammed cells underwent dedifferentiation with mitochondrial restructuring, induction of endogenous pluripotency genes - including NANOG, LIN28, and TERT, and down-regulation of cytoskeletal, MHC class I- and apoptosis-related genes. Notably, derived iPS clones acquired a rejuvenated state, characterized by elongated telomeres and suppressed senescence-related p15INK4b/p16INK4a gene expression and oxidative stress signaling. Stepwise guidance with lineage-specifying factors, including Indolactam V and GLP-1, redifferentiated HK-derived iPS clones into insulin-producing islet-like progeny. Thus, in elderly T2D patients, reprogramming of keratinocytes ensures a senescence-privileged status yielding iPS cells proficient for regenerative applications.  相似文献   
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The main purpose of this study was to investigate the relation between carotid intima-media thickness (CIMT) and coronary artery disease (CAD) complexity. Consecutive patients (n = 360) with CAD confirmed by coronary angiography were enrolled. Mean CIMT and the overall SYNTAX score (SXscore) were 0.87 ± 0.12 mm and 15 ± 9, respectively. In univariate analysis, there was a significant correlation between the overall SXscore and CIMT (r = .42, P < .001), age (r = .23, P < .001), hypertension (r = .27, P = 0.001), diabetes (r = 0.11, P = 0.02), smoking (r = .24, P = .01), dyslipidemia (r = .2, P = 0.03), and β-blocker use (r = .19, P < .001). In multivariate analysis, CIMT (β = .34, P < .001) and age (β = .11, P < .019) were independently associated with SXscore. We have demonstrated a significant relation between CIMT and SXscore. Although this study is correlative and no causative conclusions can be drawn, our findings suggest that increased CIMT could reflect complex coronary artery lesions.  相似文献   
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Background and aims

Autofluorescence imaging (AFI) is a novel technology which can capture fluorescence emitted from intestinal tissues. While AFI is useful for detecting colorectal neoplasms, it is unclear whether AFI can facilitate the diagnosis by differentiating the extent of dysplasia of colorectal neoplasms. This study investigated the efficacy of AFI in discriminating high-grade from low-grade adenoma.

Materials and methods

Sixty-seven patients who underwent colonoscopy with AFI were enrolled in this study. The AFI images obtained from 158 lesions in these patients were visually classified into four categories, namely, green (G), green with magenta spots (GM), magenta with green spots (MG), and magenta (M), according to their color intensities, immediately after the examination. The AFI images of the lesions were quantified using an image-analytical software program (F index). Either the F index or the visual assessment was prospectively compared with the dysplastic grade.

Results

The F index of the high-grade adenomas was significantly lower than that of the low-grade adenomas, hyperplasia, and normal mucosa (p?Conclusions AFI, particularly the F index, is considered to be a useful procedure for estimating the dysplastic grade of colonic adenomas.  相似文献   
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