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31.
Surface-based morphometry (SBM) is extremely useful for estimating the indices of cortical morphology, such as volume, thickness, area, and gyrification, whereas voxel-based morphometry (VBM) is a typical method of gray matter (GM) volumetry that includes cortex measurement. In cases where SBM is used to estimate cortical morphology, it remains controversial as to whether VBM should be used in addition to estimate GM volume. Therefore, this review has two main goals. First, we summarize the differences between the two methods regarding preprocessing, statistical analysis, and reliability. Second, we review studies that estimate cortical morphological changes using VBM and/or SBM and discuss whether using VBM in conjunction with SBM produces additional values. We found cases in which detection of morphological change in either VBM or SBM was superior, and others that showed equivalent performance between the two methods. Therefore, we concluded that using VBM and SBM together can help researchers and clinicians obtain a better understanding of normal neurobiological processes of the brain. Moreover, the use of both methods may improve the accuracy of the detection of morphological changes when comparing the data of patients and controls.In addition, we introduce two other recent methods as future directions for estimating cortical morphological changes: a multi-modal parcellation method using structural and functional images, and a synthetic segmentation method using multi-contrast images (such as T1- and proton density-weighted images).  相似文献   
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Recently, fasting has been spotlighted from a healthcare perspective. However, the de-tailed biological mechanisms and significance by which the effects of fasting confer health benefits are not yet clear. Due to certain advantages of the zebrafish as a vertebrate model, it is widely utilized in biological studies. However, the biological responses to nutrient metabolism within zebrafish skeletal muscles have not yet been amply reported. Therefore, we aimed to reveal a gene expression profile in zebrafish skeletal muscles in response to fasting-refeeding. Accordingly, mRNA-sequencing and bioinformatics analysis were performed to examine comprehensive gene expression changes in skeletal muscle tissues during fasting-refeeding. Our results produced a novel set of nutrition-related genes under a fasting-refeeding protocol. Moreover, we found that five genes were dramatically upregulated in each fasting (for 24 h) and refeeding (after 3 h), exhibiting a rapid response to the provided conditional changes. The assessment of the gene length revealed that the gene set whose expression was elevated only after 3 h of refeeding had a shorter length, suggesting that nutrition-related gene function is associated with gene length. Taken together, our results from the bioinformatics analyses provide new insights into biological mechanisms induced by fasting-refeeding conditions within zebrafish skeletal muscle.  相似文献   
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Background and HypothesisMachine learning approaches using structural magnetic resonance imaging (MRI) can be informative for disease classification; however, their applicability to earlier clinical stages of psychosis and other disease spectra is unknown. We evaluated whether a model differentiating patients with chronic schizophrenia (ChSZ) from healthy controls (HCs) could be applied to earlier clinical stages such as first-episode psychosis (FEP), ultra-high risk for psychosis (UHR), and autism spectrum disorders (ASDs).Study DesignTotal 359 T1-weighted MRI scans, including 154 individuals with schizophrenia spectrum (UHR, n = 37; FEP, n = 24; and ChSZ, n = 93), 64 with ASD, and 141 HCs, were obtained using three acquisition protocols. Of these, data regarding ChSZ (n = 75) and HC (n = 101) from two protocols were used to build a classifier (training dataset). The remainder was used to evaluate the classifier (test, independent confirmatory, and independent group datasets). Scanner and protocol effects were diminished using ComBat.Study ResultsThe accuracy of the classifier for the test and independent confirmatory datasets were 75% and 76%, respectively. The bilateral pallidum and inferior frontal gyrus pars triangularis strongly contributed to classifying ChSZ. Schizophrenia spectrum individuals were more likely to be classified as ChSZ compared to ASD (classification rate to ChSZ: UHR, 41%; FEP, 54%; ChSZ, 70%; ASD, 19%; HC, 21%).ConclusionWe built a classifier from multiple protocol structural brain images applicable to independent samples from different clinical stages and spectra. The predictive information of the classifier could be useful for applying neuroimaging techniques to clinical differential diagnosis and predicting disease onset earlier.  相似文献   
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BACKGROUND: Aspirin and anti-platelet drugs are used commonly for patients with coronary heart disease. Proton pump inhibitor (PPI) and high-dose H2-blocker were recommended for preventing NSAIDs-related ulcer. Previously H2-blocker reported to have some negative cardiovascular effects. Additionally, a recent in vitro study showed that PPI reduced cardiac contractility. In this study, we evaluated whether chronic administration of PPI and high-dose H2-blocker affects left ventricular function. METHOD: Fifty-two stable angina patients were enrolled and classified into PPI group ([P]; lansoprazole: 15mg/day, n=28), H2-blocker group ([H]; famotidine: 40mg/day, n=8), and control ([C]; none or mucosal-defense drug, n=16). Eligible patients showed normal cardiac function in initial catheterization without administrated PPI or H2-blocker. They received percutaneous coronary intervention and follow-up catheterization. We compared changes in ejection fraction (EF: %), end diastolic/systolic volume index (EDVI/ESVI: ml/m(2)), and peak positive/negative dp/dt (+/-dp/dt: mmHg/s) in left ventricular angiography series. RESULT: There were no significant differences among three groups regarding patient characteristics, backgrounds of angiographic and intervention, except for fewer smokers in [C]. Other drugs such as beta- and Ca-blocker did not have effects on cardiac function except for aspirin during 255+/-115 days follow-up. Rate of EF changes significantly decreased in [P], and tended to decrease in [H] (C: 3.8+/-9.8%, H: -1.6+/-7.6%, P: -2.1+/-5.9%; p<0.05 for [C] vs. [P]). Those of ESVI changes were significantly greater in [P], and tended to be greater in [H] (C: -4.5+/-16.2%, H: 4.9+/-15.5%, P: 7.3+/-16.2%; p<0.05 for [C] vs. [P]), though, EDVI changes' were similar (C: 2.5+/-8.9%, H: 2.6+/-3.6%, P: 1.6+/-6.1%; p=ns). Rate of +/-dp/dt-changes tended to decrease in [H] (+dp/dt: C: 3.9+/-15.5%, H: -10.0+/-25.2%, P: 0.3+/-19.6%; p=ns, -dp/dt: C: -0.1+/-19.5%, H: -8.5+/-20.4%, P: 5.7+/-27.7%; p=ns). CONCLUSION: In this study, PPI and high-dose H2-blocker have EF-reducing tendency. However, these changes were small and these drugs seemed to exhibit little influence clinically.  相似文献   
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Neuromedin s is a novel anorexigenic hormone   总被引:4,自引:0,他引:4  
A novel 36-amino acid neuropeptide, neuromedin S (NMS), has recently been identified in rat brain and has been shown to be an endogenous ligand for two orphan G protein-coupled receptors, FM-3/GPR66 and FM-4/TGR-1. These receptors have been identified as neuromedin U (NMU) receptor type 1 and type 2, respectively. In this study, the physiological role of the novel peptide, NMS, on feeding regulation was investigated. Intracerebroventricular (icv) injection of NMS decreased 12-h food intake during the dark period in rats. This anorexigenic effect was more potent and persistent than that observed with the same dose of NMU. Neuropeptide Y, ghrelin, and agouti-related protein-induced food intake was counteracted by coadministration of NMS. Icv administration of NMS increased proopiomelanocortin mRNA expression in the arcuate nucleus (Arc) and CRH mRNA in the paraventricular nucleus (PVN). Pretreatment with SHU9119 (antagonist for alpha-MSH) and alpha-helical corticotropin-releasing factor-(9-41) (antagonist for CRH) attenuated NMS-induced suppression of 24-h food intake. After icv injection of NMS, Fos-immunoreactive cells were detected in both the PVN and Arc. When neuronal multiple unit activity was recorded in the PVN before and after icv injection of NMS, a significant increase in firing rate was observed 5 min after administration, and this increase continued for 100 min. These results suggest that the novel peptide, NMS, may be a potent anorexigenic hormone in the hypothalamus, and that expression of proopiomelanocortin mRNA in the Arc and CRH mRNA in the PVN may be involved in NMS action on feeding.  相似文献   
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