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991.
Guilherme Silva Julian Renato Watanabe de Oliveira Juliana Cini Perry Sergio Tufik Jair Ribeiro Chagas 《PloS one》2014,9(10)
Obstructive sleep apnea (OSA) is a syndrome characterized by intermittent nocturnal hypoxia, sleep fragmentation, hypercapnia and respiratory effort, and it has been associated with several complications, such as diabetes, hypertension and obesity. Quantitative real-time PCR has been performed in previous OSA-related studies; however, these studies were not validated using proper reference genes. We have examined the effects of chronic intermittent hypoxia (CIH), which is an experimental model mainly of cardiovascular consequences of OSA, on reference genes, including beta-actin, beta-2-microglobulin, glyceraldehyde-3-phosphate dehydrogenase, hypoxanthine guanine phosphoribosyl transferase and eukaryotic 18S rRNA, in different areas of the brain. All stability analyses were performed using the geNorm, Normfinder and BestKeeper software programs. With exception of the 18S rRNA, all of the evaluated genes were shown to be stable following CIH exposure. However, gene stability rankings were dependent on the area of the brain that was analyzed and varied according to the software that was used. This study demonstrated that CIH affects various brain structures differently. With the exception of the 18S rRNA, all of the tested genes are suitable for use as housekeeping genes in expression analyses. 相似文献
992.
Tony M. Dinis Guillaume Vidal Rodrigo R. Jose Pascale Vigneron Damien Bresson Vincent Fitzpatrick Frédéric Marin David L. Kaplan Christophe Egles 《PloS one》2014,9(10)
With the aim of forming bioactive guides for peripheral nerve regeneration, silk fibroin was electrospun to obtain aligned nanofibers. These fibers were functionalized by incorporating Nerve Growth Factor (NGF) and Ciliary NeuroTrophic Factor (CNTF) during electrospinning. PC12 cells grown on the fibers confirmed the bioavailability and bioactivity of the NGF, which was not significantly released from the fibers. Primary neurons from rat dorsal root ganglia (DRGs) were grown on the nanofibers and anchored to the fibers and grew in a directional fashion based on the fiber orientation, and as confirmed by growth cone morphology. These biofunctionalized nanofibers led to a 3-fold increase in neurite length at their contact, which was likely due to the NGF. Glial cell growth, alignment and migration were stimulated by the CNTF in the functionalized nanofibers. Organotypic culture of rat fetal DRGs confirmed the complementary effect of both growth factors in multifunctionalized nanofibers, which allowed glial cell migration, alignment and parallel axonal growth in structures resembling the ‘bands of Bungner’ found in situ. Graftable multi-channel conduits based on biofunctionalized aligned silk nanofibers were developed as an organized 3D scaffold. Our bioactive silk tubes thus represent new options for a biological and biocompatible nerve guidance conduit. 相似文献
993.
Haydée A. Cunha Bruna V. Medeiros Lupércio A. Barbosa Marta J. Cremer Juliana Marigo José Lailson-Brito Alexandre F. Azevedo Antonio M. Solé-Cava 《PloS one》2014,9(1)
Franciscanas are the most endangered dolphins in the Southwestern Atlantic. Due to their coastal and estuarine habits, franciscanas suffer from extensive fisheries bycatch, as well as from habitat loss and degradation. Four Franciscana Management Areas (FMA), proposed based on biology, demography, morphology and genetic data, were incorporated into management planning and in the delineation of research efforts. We re-evaluated that proposal through the analysis of control region sequences from franciscanas throughout their distribution range (N = 162), including novel sequences from the northern limit of the species and two other previously unsampled localities in Brazil. A deep evolutionary break was observed between franciscanas from the northern and southern portions of the species distribution, indicating that they must be managed as two Evolutionarily Significant Units (ESU). Furthermore, additional FMAs should be recognised to accommodate the genetic differentiation found in each ESU. These results have immediate consequences for the conservation and management of this endangered species. 相似文献
994.
David Patsouris Jingwei-Ji Cao Guillaume Vial Amelie Bravard Etienne Lefai Annie Durand Christine Durand Marie-Agnés Chauvin Fabienne Laugerette Cyrille Debard Marie-Caroline Michalski Martine Laville Hubert Vidal Jennifer Rieusset 《PloS one》2014,9(10)
Inflammation is now recognized as a major factor contributing to type 2 diabetes (T2D). However, while the mechanisms and consequences associated with white adipose tissue inflammation are well described, very little is known concerning the situation in skeletal muscle. The aim of this study was to investigate, in vitro and in vivo, how skeletal muscle inflammation develops and how in turn it modulates local and systemic insulin sensitivity in different mice models of T2D and in humans, focusing on the role of the chemokine MCP1. Here, we found that skeletal muscle inflammation and macrophage markers are increased and associated with insulin resistance in mice models and humans. In addition, we demonstrated that intra-muscular TNFα expression is exclusively restricted to the population of intramuscular leukocytes and that the chemokine MCP1 was associated with skeletal muscle inflammatory markers in these models. Furthermore, we demonstrated that exposure of C2C12 myotubes to palmitate elevated the production of the chemokine MCP1 and that the muscle-specific overexpression of MCP1 in transgenic mice induced the local recruitment of macrophages and altered local insulin sensitivity. Overall our study demonstrates that skeletal muscle inflammation is clearly increased in the context of T2D in each one of the models we investigated, which is likely consecutive to the lipotoxic environment generated by peripheral insulin resistance, further increasing MCP1 expression in muscle. Consequently, our results suggest that MCP1-mediated skeletal muscle macrophages recruitment plays a role in the etiology of T2D. 相似文献
995.
John C. Hu Camila Mathias-Santos Christopher J. Greene Natalie D. King-Lyons Juliana F. Rodrigues George Hajishengallis Luís C. S. Ferreira Terry D. Connell 《PloS one》2014,9(12)
Vaccinations are extremely effective at combating infectious diseases. Many conserved antigen (Ag) targets, however, are poorly immunogenic. Protein subunit vaccines frequently elicit only humoral immune responses and fail to confer protection against serious intracellular pathogens. These barriers to vaccine development are often overcome by the use of appropriate adjuvants. Heat-labile enterotoxins (HLT) produced by enterotoxigenic strains of Escherichia coli are potent adjuvants when administered by mucosal or systemic routes. The efficacy of the type II HLT, however, has not been well-defined when administered by the intradermal (ID) route. Using a murine ID immunization model, the adjuvant properties of LT-IIb and LT-IIc, two type II HLTs, were compared with those of LT-I, a prototypical type I HLT. While all three HLT adjuvants enhanced Ag-specific humoral responses to similar levels, LT-IIb and LT-IIc, in contrast to LT-I, induced a more vigorous Ag-specific CD8+ T cell response and proffered faster clearance of Listeria monocytogenes in a challenge model. Additionally, LT-IIb and LT-IIc induced distinct differences in the profiles of the Ag-specific CD8+ T cell responses. While LT-IIc stimulated a robust and rapid primary CD8+ T cell response, LT-IIb exhibited slower CD8+ T cell expansion and contraction kinetics with the formation of higher percentages of effector memory cells. In comparison to LT-I and LT-IIc, LT-IIb evoked better long-term protection after immunization. Furthermore, LT-IIb and LT-IIc enhanced the total number of dendritic cells (DC) in the draining lymph node (DLN) and expression of costimulatory molecules CD80, CD86, and CD40 on DCs. In contrast to LT-I, LT-IIb and LT-IIc induced less edema, cellular infiltrates, and general inflammation at the site of ID injection. Thus, LT-IIb and LT-IIc are attractive comprehensive ID adjuvants with unique characteristic that enhance humoral and cellular immunity to a co-administered protein Ag. 相似文献
996.
Vanessa Oliveira Eliana Hiromi Akamine Maria Helena C. Carvalho Lisete Compagno Michelini Zuleica Bruno Fortes Tatiana Sousa Cunha Maria do Carmo Franco 《PloS one》2014,9(11)
Intrauterine growth restriction (IUGR) is associated with impaired vascular function, which contributes to the increased incidence of chronic disease. The aim of this study was to investigate whether aerobic training improves AngII-induced vasoconstriction in IUGR rats. Moreover, we assess the role of superoxide dismutase (SOD) isoforms and NADPH oxidase-derived superoxide anions in this improvement. Female Wistar rats were randomly divided into two groups on day 1 of pregnancy. A control group was fed standard chow ad libitum, and a restricted group was fed 50% of the ad libitum intake throughout gestation. At 8 weeks of age, male offspring from both groups were randomly assigned to 4 experimental groups: sedentary control (SC), trained control (TC), sedentary restricted (SRT), and trained restricted (TRT). The training protocol was performed on a treadmill and consisted of a continuous 60-min session 5 days/week for 10 weeks. Following aerobic training, concentration–response curves to AngII were obtained in endothelium-intact aortic rings. Protein expression of SOD isoforms, AngII receptors and the NADPH oxidase component p47phox was assessed by Western blot analysis. The dihydroethidium was used to evaluate the in situ superoxide levels under basal conditions or in the presence of apocynin, losartan or PD 123,319. Our results indicate that aerobic training can prevent IUGR-associated increases in AngII-dependent vasoconstriction and can restore basal superoxide levels in the aortic rings of TRT rats. Moreover, we observed that aerobic training normalized the increased p47phox protein expression and increased MnSOD and AT2 receptor protein expression in thoracic aortas of SRT rats. In summary, aerobic training can result in an upregulation of antioxidant defense by improved of MnSOD expression and attenuation of NADPH oxidase component p47phox. These effects are accompanied by increased expression of AT2 receptor, which provide positive effects against Ang II–induced superoxide generation, resulting in attenuation of AngII-induced vasoconstriction. 相似文献
997.
Development and Validation of the Self-Acceptance Scale for Persons with Early Blindness: The SAS-EB
Fabiane Frota da Rocha Morgado Angela Nogueira Neves Betanho Campana Maria da Consola??o Gomes Cunha Fernandes Tavares 《PloS one》2014,9(9)
Investigations of self-acceptance are critical to understanding the development and maintenance of psychological health. However, valid and reliable instruments for measuring self-acceptance in persons with early blindness have yet to be developed. The current research describes three studies designed to develop and validate the Self-acceptance Scale for Persons with Early Blindness (SAS-EB). In Study 1, we developed the initial item pool. Thirty-three items were generated, based on data from specialized literature and from 2 focus groups. Items were organized in a three-factor structure, theoretically predicted for SAS-EB - (1) body acceptance, (2) self-protection from social stigmas, and (3) feeling and believing in one''s capacities. In Study 2, information obtained from a panel of 9 experts and 22 persons with early blindness representing the target population was used to refine the initial item pool, generating a new pool of 27 items. In Study 3, 318 persons with early blindness (141 women and 177 men), between 18 and 60 years of age (M = 37.74 years, SD = 12.37) answered the new pool of 27 items. After the elimination of 9 items using confirmatory factor analysis, we confirmed the theoretical three-factor structure of the SAS-EB. Study 3 also provided support for the scale''s internal consistency and construct validity. Finally, the psychometric properties of the SAS-EB, its utility, and its limitations are discussed along with considerations for future research. 相似文献
998.
Jacqueline de Melo Barcelar Andrea Aliverti Catarina Rattes Maria Eduarda Ximenes Shirley Lima Campos Daniella Cunha Brand?o Guilherme Fregonezi Armèle Dornelas de Andrade 《PloS one》2014,9(11)
Objective
To analyze in obese women the acute effects of the breath stacking technique on thoraco-abdominal expansion.Design and Methods
Nineteen obese women (BMI≥30 kg/m2) were evaluated by anthropometry, spirometry and maximal respiratory muscle pressures and successively analyzed by Opto-Electronic Plethysmography and a Wright respirometer during quiet breathing and breath stacking maneuvers and compared with a group of 15 normal-weighted healthy women. The acute effects of the maneuvers were assessed in terms of total and compartmental chest wall volumes at baseline, end of the breath stacking maneuver and after the maneuver. Obese subjects were successively classified into two groups, accordingly to the response during the maneuver, group 1 = prevalent rib cage or group 2 = abdominal expansion.Results
Age was significantly lower in group 1 than group 2. When considering the two obese groups, FEV1 was lower and minute ventilation was higher only in group 2 compared to controls group. During breath stacking, inspiratory capacity was significant differences in obese subjects with a smaller expansion of the pulmonary rib cage and a greater expansion of the abdomen compared to controls and also between groups 1 and 2. A significant inverse linear relationship was found between age and inspiratory capacity of the pulmonary rib cage but not of the abdomen.Conclusions
In obese women the maximal expansion of the rib cage and abdomen is influenced by age and breath stacking maneuver could be a possible therapy for preventing respiratory complications. 相似文献999.
Juliana Perez Di Giorgio Gabriela Soto Karina Alleva Cintia Jozefkowicz Gabriela Amodeo Jorge Prometeo Muschietti Nicolás Daniel Ayub 《The Journal of membrane biology》2014,247(2):107-125
Aquaporins (AQPs) are a family of channel proteins, which transport water and/or small solutes across cell membranes. AQPs are present in Bacteria, Eukarya, and Archaea. The classical AQP evolution paradigm explains the inconsistent phylogenetic trees by multiple transfer events and emphasizes that the assignment of orthologous AQPs is not possible, making it difficult to integrate functional information. Recently, a novel phylogenetic framework of eukaryotic AQP evolution showed congruence between eukaryotic AQPs and organismal trees identifying 32 orthologous clusters in plants and animals (Soto et al. Gene 503:165–176, 2012). In this article, we discuss in depth the methodological strength, the ability to predict functionality and the AQP community perception about the different paradigms of AQP evolution. Moreover, we show an updated review of AQPs transport functions in association with phylogenetic analyses. Finally, we discuss the possible effect of AQP data integration in the understanding of water and solute transport in eukaryotic cells. 相似文献
1000.
Juliana Falcato Vecina Alexandre Gabarra Oliveira Tiago Gomes Araujo Sueli Regina Baggio Cristiane Okuda Torello Mario Jose Abdalla Saad Mary Luci de Souza Queiroz 《Life sciences》2014