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241.
Joana Pacheco João Raimundo Filipe Santos Mário Ferreira Tiago Lopes Luis Ramos 《Somatosensory & motor research》2013,30(2):103-108
AbstractObjective: The aims of this study are to investigate the association between: (i) forward head posture (FHP) and pressure pain thresholds (PPTs); (ii) FHP and maladaptive cognitive processes; and (iii) FHP and neck pain characteristics in university students with subclinical neck pain.Materials/methods: A total of 140 university students, 90 asymptomatic and 50 with subclinical neck pain, entered the study. Demographic data, anthropometric data, FHP, and PPTs were collected for both groups. In addition, pain characteristics, pain catastrophizing, and fear of movement were assessed for participants with neck pain. FHP was characterized by the angle between C7, the tragus of the ear, and the horizontal line. Correlation analysis and multivariate regression analysis were conducted.Results: Participants with subclinical neck pain showed significantly lower PPTs than participants without neck pain (p?<?.05), but similar FHP (p?>?.05). No significant association was found between FHP and PPTs in the asymptomatic group. In the group of participants with subclinical neck pain, PPTs at the right trapezius and neck pain duration explained 19% of the variance of FHP (R2?=?0.23; adjusted R2?=?0.19; p?<?.05).Conclusion: This study suggests that FHP is not associated with PPTs in asymptomatic university students. In university students with subclinical neck pain, increased FHP was associated with right trapezius hypoalgesia and with neck pain of shorter duration. These findings are in contrast with current assumptions on the association between neck pain and FHP. 相似文献
242.
Maria Filomena de Jesus Raposo Rui Manuel Santos Costa de MoraisAlcina Maria Miranda Bernardo de Morais 《Life sciences》2013
Marine microalgae and cyanobacteria are very rich in several chemical compounds and, therefore, they may be used in several biological applications related with health benefits, among others. This review brings the research up-to-date on the bioactive compounds produced by marine unicellular algae, directly or indirectly related to human health. It covers and goes through the most studied applications of substances such as PUFA, sterols, proteins and enzymes, vitamins and pigments, in areas so diverse as human and animal nutrition, therapeutics, and aquaculture. The great potential of marine microalgae and the biocoumpounds they produce are discussed in this review. 相似文献
243.
Alexandre Alberto Tonin Aleksandro Schafer da Silva Maria Luiza Thorstenberg Lívia Gelain Castilhos Raqueli Teresinha Fran?a Daniela Bitencourt Rosa Leal Marta Maria Medeiros Frescura Duarte Fernanda Silveira Flores Vogel Mario Luiz de La Rue Sonia Terezinha dos Anjos Lopes 《The Korean journal of parasitology》2013,51(4):421-426
Several studies have shown the mechanisms and importance of immune responses against Toxoplasma gondii infection and the notable role of cholinesterases in inflammatory reactions. However, the association between those factors has not yet been investigated. Therefore, the aim of this study was to evaluate the acetylcholinesterase (AChE) activity in blood and lymphocytes and the activity of butyrylcholinesterase (BChE) in serum of rats experimentally infected with T. gondii during the acute phase of infection. For that, an in vivo study was performed with evaluations of AChE and BChE activities on days 5 and 10 post-infection (PI). The activity of AChE in blood was increased on day 5 PI, while in lymphocytes its activity was enhanced on days 5 and 10 PI (P<0.05). No significant difference was observed between groups regarding to the activity of BChE in serum. A positive (P<0.01) correlation was observed between AChE activity and number of lymphocytes. The role of AChE as an inflammatory marker is well known in different pathologies; thus, our results lead to the hypothesis that AChE has an important role in modulation of early immune responses against T. gondii infection. 相似文献
244.
Aline Augusti Boligon Thaís Felli Kubiça Débora Nunes Mario Thiele Faccim de Brum Mariana Piana Rudi Weiblen Luciane Lovato Sydney Hartz Alves Roberto Christ Vianna Santos Camilla Filippi dos Santos Alves Margareth Linde Athayde 《Acta Physiologiae Plantarum》2013,35(7):2229-2239
Antimicrobial and antiviral activities of the fractions from Scutia buxifolia stem bark and leaves were evaluated. Best antimicrobial results occurred with the ethyl acetate (EA) and n-butanolic (NB) fractions from the leaves against Micrococcus sp. (minimal inhibitory concentration—MIC = 62.5 μg/ml), and NB fraction from stem bark and leaves against Klebsiella pneumoniae and Enterococcus faecalis (MIC = 62.5 μg/ml). The most active fractions were selected and fractioned into silica column to perform an in vitro antibiofilm assay, which evidenced subfractions EA2 and EA3 as the more active against Candida albicans (biofilm inhibitory concentration—BIC = 582 ± 0.01 μg/ml) and Staphylococcus aureus (BIC = 360 ± 0.007 μg/ml), respectively. The NB (selectivity index—SI = 25.78) and the EA (SI = 15.97) fractions from the stem bark, and the EA (SI = 14.13) fraction from the leaves exhibited a potential antiviral activity towards Herpes Simplex Virus type 1 whereas EA2 and EA3 subfractions from leaves (SI = 12.59 and 10.06, respectively), and NB2 subfraction from stem bark (SI = 12.34) maintained this good activity. Phenolic acids and flavonoids (gallic acid, chlorogenic acid, caffeic acid, rutin, isoquercitrin, quercitrin and quercetin) were identified by HPLC and may be partially responsible for the antimicrobial and antiherpes activities observed. The results obtained in this study showed that Scutia buxifolia has antibiofilm and anti-herpetic activities and that these properties are reported for the first time for this species. 相似文献
245.
246.
Ana C. Santos Joana Cunha F. Veiga A. Cordeiro-da-Silva Antonio J. Ribeiro 《Carbohydrate polymers》2013
Alginate-dextran sulfate (ADS) microgel has been used to protect insulin from gastrointestinal attack and as a carrier to promote insulin permeation through intestinal epithelium. The throughput of ADS submicron particles generation by emulsification/internal gelation is limited by its wide size distribution. 相似文献
247.
Susana Cardoso Maria S. Santos António Moreno Paula I. Moreira 《Journal of bioenergetics and biomembranes》2013,45(4):397-407
A growing body of evidence suggests that mitochondrial proton-leak functions as a regulator of reactive oxygen species production and its modulation may limit oxidative injury to tissues. The main purpose of this work was to characterize the proton-leak of brain cortical mitochondria from long-term hyperglycemic and insulin-induced recurrent hypoglycemic rats through the modulation of the uncoupling protein 2 (UCP2) and adenine nucleotide translocator (ANT). Streptozotocin-induced diabetic rats were treated subcutaneously with twice-daily insulin injections during 2 weeks to induce the hypoglycemic episodes. No differences in the basal proton-leak, UCP2 and ANT protein levels were observed between the experimental groups. Mitochondria from recurrent hypoglycemic rats presented a decrease in proton-leak in the presence of GDP, a specific UCP2 inhibitor, while an increase in proton-leak was observed in the presence of linoleic acid, a proton-leak activator, this effect being reverted by the simultaneous addition of GDP. Mitochondria from long-term hyperglycemic rats showed an enhanced susceptibility to ANT modulation as demonstrated by the complete inhibition of basal and linoleic acid-induced proton-leak caused by the ANT specific inhibitor carboxyatractyloside. Our results show that recurrent-hypoglycemia renders mitochondria more susceptible to UCPs modulation while the proton-leak of long-term hyperglycemic rats is mainly modulated by ANT, which suggest that brain cortical mitochondria have distinct adaptation mechanisms in face of different metabolic insults. 相似文献
248.
Jean‐Noël Octave Nathalie Pierrot Susana Ferao Santos Natalia N. Nalivaeva Anthony J. Turner 《Journal of neurochemistry》2013,126(2):183-190
Despite intensive studies of the secretase‐mediated processing of the amyloid precursor protein (APP) to form the amyloid β‐peptide (Aβ), in relation to Alzheimer's disease (AD), no new therapeutic agents have reached the clinics based on reducing Aβ levels through the use of secretase inhibitors or immunotherapy. Furthermore, the normal neuronal functions of APP and its various metabolites still remain under‐investigated and unclear. Here, we highlight emerging areas of APP function that may provide new insights into synaptic development, cognition, and gene regulation. By modulating expression levels of endogenous APP in primary cortical neurons, the frequency and amplitude of calcium oscillations is modified, implying a key role for APP in maintaining neuronal calcium homeostasis essential for synaptic transmission. Disruption of this homeostatic mechanism predisposes to aging and AD. Synaptic spine loss is a feature of neurogeneration resulting in learning and memory deficits, and emerging evidence indicates a role for APP, probably mediated via one or more of its metabolites, in spine structure and functions. The intracellular domain of APP (AICD) has also emerged as a key epigenetic regulator of gene expression controlling a diverse range of genes, including APP itself, the amyloid‐degrading enzyme neprilysin, and aquaporin‐1. A fuller understanding of the physiological and pathological actions of APP and its metabolic network could provide new opportunities for therapeutic intervention in AD. 相似文献
249.
Tiago G. Santos Flavio H. Beraldo Glaucia N. M. Hajj Marilene H. Lopes Martin Roffe Fernanda C. S. Lupinacci Valeriy G. Ostapchenko Vania F. Prado Marco A. M. Prado Vilma R. Martins 《Journal of neurochemistry》2013,124(2):210-223
Prion protein (PrPC) is a cell surface glycoprotein that is abundantly expressed in nervous system. The elucidation of the PrPC interactome network and its significance on neural physiology is crucial to understanding neurodegenerative events associated with prion and Alzheimer's diseases. PrPC co‐opts stress inducible protein 1/alpha7 nicotinic acetylcholine receptor (STI1/α7nAChR) or laminin/Type I metabotropic glutamate receptors (mGluR1/5) to modulate hippocampal neuronal survival and differentiation. However, potential cross‐talk between these protein complexes and their role in peripheral neurons has never been addressed. To explore this issue, we investigated PrPC‐mediated axonogenesis in peripheral neurons in response to STI1 and laminin‐γ1 chain‐derived peptide (Ln‐γ1). STI1 and Ln‐γ1 promoted robust axonogenesis in wild‐type neurons, whereas no effect was observed in neurons from PrPC‐null mice. PrPC binding to Ln‐γ1 or STI1 led to an increase in intracellular Ca2+ levels via distinct mechanisms: STI1 promoted extracellular Ca2+ influx, and Ln‐γ1 released calcium from intracellular stores. Both effects depend on phospholipase C activation, which is modulated by mGluR1/5 for Ln‐γ1, but depends on, C‐type transient receptor potential (TRPC) channels rather than α7nAChR for STI1. Treatment of neurons with suboptimal concentrations of both ligands led to synergistic actions on PrPC‐mediated calcium response and axonogenesis. This effect was likely mediated by simultaneous binding of the two ligands to PrPC. These results suggest a role for PrPC as an organizer of diverse multiprotein complexes, triggering specific signaling pathways and promoting axonogenesis in the peripheral nervous system. 相似文献
250.
Leticia Ramos de Arvelos Vanessa Custódio Afonso Rocha Gabriela Pereira Felix Cleine Chagas da Cunha Morun Bernardino Neto Mario da Silva Garrote Filho Conceição de Fátima Pinheiro Elmiro Santos Resende Nilson Penha-Silva 《The Journal of membrane biology》2013,246(3):231-242
The stability of the erythrocyte membrane, which is essential for the maintenance of cell functions, occurs in a critical region of fluidity, which depends largely on its composition and the composition and characteristics of the medium. As the composition of the erythrocyte membrane is influenced by several blood variables, the stability of the erythrocyte membrane must have relations with them. The present study aimed to evaluate, by bivariate and multivariate statistical analyses, the correlations and causal relationships between hematologic and biochemical variables and the stability of the erythrocyte membrane against the chaotropic action of ethanol. The validity of this type of analysis depends on the homogeneity of the population and on the variability of the studied parameters, conditions that can be filled by patients who undergo bariatric surgery by the technique of Roux-en-Y gastric bypass since they will suffer feeding restrictions that have great impact on their blood composition. Pathway analysis revealed that an increase in hemoglobin leads to decreased stability of the cell, probably through a process mediated by an increase in mean corpuscular volume. Furthermore, an increase in the mean corpuscular hemoglobin (MCH) leads to an increase in erythrocyte membrane stability, probably because higher values of MCH are associated with smaller quantities of red blood cells and a larger contact area between the cell membrane and ethanol present in the medium. 相似文献