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91.
Multimodal analysis of cortical chemoarchitecture and macroscale fMRI resting‐state functional connectivity 下载免费PDF全文
Martijn P. van den Heuvel Lianne H. Scholtens Elise Turk Dante Mantini Wim Vanduffel Lisa Feldman Barrett 《Human brain mapping》2016,37(9):3103-3113
The cerebral cortex is well known to display a large variation in excitatory and inhibitory chemoarchitecture, but the effect of this variation on global scale functional neural communication and synchronization patterns remains less well understood. Here, we provide evidence of the chemoarchitecture of cortical regions to be associated with large‐scale region‐to‐region resting‐state functional connectivity. We assessed the excitatory versus inhibitory chemoarchitecture of cortical areas as an ExIn ratio between receptor density mappings of excitatory (AMPA, M1) and inhibitory (GABAA, M2) receptors, computed on the basis of data collated from pioneering studies of autoradiography mappings as present in literature of the human (2 datasets) and macaque (1 dataset) cortex. Cortical variation in ExIn ratio significantly correlated with total level of functional connectivity as derived from resting‐state functional connectivity recordings of cortical areas across all three datasets (human I: P = 0.0004; human II: P = 0.0008; macaque: P = 0.0007), suggesting cortical areas with an overall more excitatory character to show higher levels of intrinsic functional connectivity during resting‐state. Our findings are indicative of the microscale chemoarchitecture of cortical regions to be related to resting‐state fMRI connectivity patterns at the global system's level of connectome organization. Hum Brain Mapp 37:3103–3113, 2016. © 2016 Wiley Periodicals, Inc. 相似文献
92.
Simionatto M de Paula JP Chaves MA Bortoloso M Cicchetti D Leonart MS do Nascimento AJ 《Hematology (Amsterdam, Netherlands)》2010,15(6):406-409
Manual reticulocyte counts were examined under light microscopy, using the property whereby supravital stain precipitates residual ribosomal RNA versus the automated flow methods, with the suggestion that in the latter there is greater precision and an ability to determine both mature and immature reticulocyte fractions. Three hundred and forty-one venous blood samples of patients were analyzed of whom 224 newborn and the rest adults; 51 males and 66 females, with ages between 0 and 89 years, as part of the laboratory routine for hematological examinations at the Clinical Laboratory of the Hospital Universitário do Oeste do Paraná. This work aimed to compare manual and automated methodologies for reticulocyte countings and evaluate random and systematic errors. The results obtained showed that the difference between the two methods was very small, with an estimated 0·4% systematic error and 3·9% random error. Thus, it has been confirmed that both methods, when well conducted, can reflect precisely the reticulocyte counts for adequate clinical use. 相似文献
93.
A. Siniscalchi A. Dante S. Spedicato L. Riganello A. Zanoni M. Cimatti E. Pierucci E. Bernardi Z. Miklosova C. Moretti S. Faenza 《Transplantation proceedings》2010,42(4):1197-1199
Background/aims
Liver transplantation (OLT) is a valid therapeutic option for patients with fulminant hepatic failure (FHF). The most critical phase during OLT is considered to be graft reperfusion, where in large changes in patient homeostasis occur. The aims of the present study were to evaluate the hemodynamic and cardiac changes among a large series of patients with FHF, to determine independent clinical predictors of the occurrence of postreperfusion syndrome (PSR) and its relationship to clinical and hemodynamic parameters and transplant outcomes.Methods
Systemic hemodynamic and cardiac functions were evaluated by Swan-Ganz catheterization in 58 patients before OLT. The patients were divided into two subgroups on the basis of PSR, which was defined as a mean arterial blood pressure 30% lower than the immediate previous value lasting for at least 1 minute within 5 minutes after unclamping.Results
PSR occurred in 24 patients (41%). Significant differences upon bivariate analysis was observed for the Model for End-stage Liver Disease score, which was significantly higher among patients with PSR, namely 32 (range = 18-43) versus 23 (range = 12-32) (P = .001). Higher serum creatinine values were significantly different among patients with PSR: 1.4 (range = 1.2-2.2) versus 2.1 (range = 2.5-3.2) mg/dL (P < .01).Conclusion
Systemic hemodynamic alterations of FHF progressively worsen with increasing severity of liver disease. PSR developed in approximately 40% of patients; its prevalence was significantly related to the severity of the disease. Finally, patients with renal failure showed greater risk to develop an PSR during OLT. 相似文献94.
Single-wall carbon nanotubes (SWCNTs) are one of the most extensively produced carbon materials and the environmental, public and professional exposure is therefore dramatically increasing. Consequently the studies on bio-effects and safety of SWCNTs are highly needed. The goal of this study was investigate the effects in vitro of SWCNTs in cells of the oral cavity, never employed in this research field. We exposed human gingival fibroblasts to 50, 75, 100, 125, 150 μg/ml SWCNTs for 24 h and we investigated genotoxicity (Comet assay and micronucleus test), cytotoxicity, oxidative stress, as reactive oxygen species (ROS) generation, and stress response, as Heat shock protein 70 (Hsp70) expression. SWCNTs produced genotoxic effects at all doses, even if detected with different sensitiveness by the two tests, and at the two highest doses induced a strong decrease of the cell proliferation and cell survival, causing apoptosis too. Furthermore, we proved the ability of these nanomaterials to induce oxidative stress and Hsp70 expression. Finally, by inhibition of Hsp70 expression, we demonstrated that this heat shock protein conferred protection against SWCNT geno-cytotoxicity. 相似文献
95.
96.
Leslie Beard Kumanan Wilson Dante Morra Jennifer Keelan 《Journal of medical Internet research》2009,11(2)
Background
Increasingly, governments, health care agencies, companies, and private groups have chosen Second Life as part of their Web 2.0 communication strategies. Second Life offers unique design features for disseminating health information, training health professionals, and enabling patient education for both academic and commercial health behavior research.Objectives
This study aimed to survey and categorize the range of health-related activities on Second Life; to examine the design attributes of the most innovative and popular sites; and to assess the potential utility of Second Life for the dissemination of health information and for health behavior change.Methods
We used three separate search strategies to identify health-related sites on Second Life. The first used the application’s search engine, entering both generic and select illness-specific keywords, to seek out sites. The second identified sites through a comprehensive review of print, blog, and media sources discussing health activities on Second Life. We then visited each site and used a snowball method to identify other health sites until we reached saturation (no new health sites were identified). The content, user experience, and chief purpose of each site were tabulated as well as basic site information, including user traffic data and site size.Results
We found a wide range of health-related activities on Second Life, and a diverse group of users, including organizations, groups, and individuals. For many users, Second Life activities are a part of their Web 2.0 communication strategy. The most common type of health-related site in our sample (n = 68) were those whose principle aim was patient education or to increase awareness about health issues. The second most common type of site were support sites, followed by training sites, and marketing sites. Finally, a few sites were purpose-built to conduct research in SL or to recruit participants for real-life research.Conclusions
Studies show that behaviors from virtual worlds can translate to the real world. Our survey suggests that users are engaged in a range of health-related activities in Second Life which are potentially impacting real-life behaviors. Further research evaluating the impact of health-related activities on Second Life is warranted. 相似文献97.
98.
Igoillo-Esteve M Maugeri D Stern AL Beluardi P Cazzulo JJ 《Anais da Academia Brasileira de Ciências》2007,79(4):649-663
Trypanosoma cruzi is highly sensitive to oxidative stress caused by reactive oxygen species. Trypanothione, the parasite's major protection against oxidative stress, is kept reduced by trypanothione reductase, using NADPH; the major source of the reduced coenzyme seems to be the pentose phosphate pathway. Its seven enzymes are present in the four major stages in the parasite's biological cycle; we have cloned and expressed them in Escherichia coli as active proteins. Glucose 6-phosphate dehydrogenase, which controls glucose flux through the pathway by its response to the NADP/NADPH ratio, is encoded by a number of genes per haploid genome, and is induced up to 46-fold by hydrogen peroxide in metacyclic trypomastigotes. The genes encoding 6-phosphogluconolactonase, 6-phosphogluconate dehydrogenase, transaldolase and transketolase are present in the CL Brener clone as a single copy per haploid genome. 6-phosphogluconate dehydrogenase is very unstable, but was stabilized introducing two salt bridges by site-directed mutagenesis. Ribose-5-phosphate isomerase belongs to Type B; genes encoding Type A enzymes, present in mammals, are absent. Ribulose-5-phosphate epimerase is encoded by two genes. The enzymes of the pathway have a major cytosolic component, although several of them have a secondary glycosomal localization, and also minor localizations in other organelles. 相似文献
99.
100.
P. Papoff G. Guelfi R. Cicchetti E. Caresta D.A. Cozzi C. Moretti F. Midulla S. Miano C. Cerasaro P. Cascone 《International journal of oral and maxillofacial surgery》2013,42(11):1418-1423
The objective was to review and compare outcomes after tongue–lip adhesion (TLA) and mandibular distraction osteogenesis (MDO) in infants with severe breathing difficulties related to Pierre Robin sequence (PRS). A single-centre retrospective (2002–2012) study was carried out; 18 infants with severe breathing difficulties related to PRS resistant to conservative treatment, who underwent TLA or MDO to correct airway obstruction, were enrolled. The primary outcome measures were successful weaning from respiratory support and resumption of full oral feeding. Nine underwent TLA and nine MDO. Eight of the nine infants who underwent MDO and all those treated with TLA were successfully weaned from respiratory support. After discharge, residual respiratory distress was diagnosed more commonly after TLA than after MDO (6/9 vs 1/9, P = 0.050). Infants resumed oral feeding sooner after MDO than after TLA (mean days after surgery to full oral feeds 44 ± 24 vs 217 ± 134, P < 0.003). The length of hospital stay was longer for infants treated with MDO than for those treated with TLA. The rate of complications was similar. Infants with severe airway obstruction related to PRS can benefit safely from either TLA or MDO. Although MDO lengthens the time to discharge, this option stabilizes airway patency of infants with PRS more efficiently and achieves full oral feeding more rapidly than TLA. 相似文献