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41.
Fabio E. Leal Lishomwa C. Ndhlovu Aaron M. Hasenkrug Fernanda R. Bruno Karina I. Carvalho Harry Wynn-Williams Walter K. Neto Sabri S. Sanabani Aluisio C. Segurado Douglas F. Nixon Esper G. Kallas 《PLoS neglected tropical diseases》2013,7(2)
HTLV-1 infection is associated with several inflammatory disorders, including the neurodegenerative condition HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP). It is unclear why a minority of infected subjects develops HAM/TSP. CD4+ T cells are the main target of infection and play a pivotal role in regulating immunity to HTLV and are hypothesized to participate in the pathogenesis of HAM/TSP. The CD39 ectonucleotidase receptor is expressed on CD4+ T cells and based on co-expression with CD25, marks T cells with distinct regulatory (CD39+CD25+) and effector (CD39+CD25−) function. Here, we investigated the expression of CD39 on CD4+ T cells from a cohort of HAM/TSP patients, HTLV-1 asymptomatic carriers (AC), and matched uninfected controls. The frequency of CD39+ CD4+ T cells was increased in HTLV-1 infected patients, regardless of clinical status. More importantly, the proportion of the immunostimulatory CD39+CD25− CD4+ T-cell subset was significantly elevated in HAM/TSP patients as compared to AC and phenotypically had lower levels of the immunoinhibitory receptor, PD-1. We saw no difference in the frequency of CD39+CD25+ regulatory (Treg) cells between AC and HAM/TSP patients. However, these cells transition from being anergic to displaying a polyfunctional cytokine response following HTLV-1 infection. CD39−CD25+ T cell subsets predominantly secreted the inflammatory cytokine IL-17. We found that HAM/TSP patients had significantly fewer numbers of IL-17 secreting CD4+ T cells compared to uninfected controls. Taken together, we show that the expression of CD39 is upregulated on CD4+ T cells HAM/TSP patients. This upregulation may play a role in the development of the proinflammatory milieu through pathways both distinct and separate among the different CD39 T cell subsets. CD39 upregulation may therefore serve as a surrogate diagnostic marker of progression and could potentially be a target for interventions to reduce the development of HAM/TSP. 相似文献
42.
Severo Juliana Soares Morais Jennifer Beatriz Silva Beserra Jessica Batista dos Santos Loanne Rocha de Sousa Melo Stéfany Rodrigues de Sousa Gustavo Santos de Matos Neto Emídio Marques Henriques Gilberto Simeone do Nascimento Marreiro Dilina 《Biological trace element research》2020,193(1):81-88
Biological Trace Element Research - Excessive adipose tissue promotes the manifestation of endocrine disorders such as reduction of the secretion of zinc-α2-glycoprotein (ZAG), an adipokine... 相似文献
43.
Aureo Banhos Bruno L. Fontes Débora Regina Yogui Mario Henrique Alves Natália Carneiro Ardente Renata Valls Lucas Mendes Barreto Lucas Damásio Átilla Colombo Ferreguetti Andréa Siqueira Carvalho Vitor Roberto Schettino Alexandre Rosa dos Santos Helena Godoy Bergallo Ana Carolina Srbek-Araujo Emilia Patrícia Medici Ariel Canena Arnaud L.J. Desbiez 《Biotropica》2020,52(3):421-426
We report 24 records of giant armadillo roadkill on Brazilian highways in the Cerrado, Pantanal and Amazon biomes illustrating that highways are a threat to this species. However, we also documented the species using underpasses, demonstrating that these structures could help to reduce the risk of roadkill for giant armadillos. 相似文献
44.
Francielle C. Mosele Rafael Bissi Ricci Phablo Abreu José C. Rosa Neto 《Journal of cellular physiology》2020,235(9):6183-6193
Activation, proliferation, and differentiation of satellite cells can be influenced by extracellular factors, such as adiponectin. This adipokine has been proposed as a regulator of in vitro myogenesis, but its action on in vivo regeneration is not still elucidated. We used C57BL/6 (wild-type [WT]) and adiponectin knockout (AdKO) mice injured with barium chloride at periods of 3, 7, and 14 days after injury. The AdKO presented a higher number of centralized nuclei after 7 days, and a reduction in myogenic genes was observed after 3 days. Moreover, these mice presented an increase in anti-inflammatory cytokines after 3 and 7 days, and an increase in the M2 gene marker and proinflammatory cytokines after 7 days. The WT demonstrated an increase in adiponectin messenger RNA after 7 days. These results demonstrate that adiponectin is important in tissue remodeling during regeneration and that its deficiency does not compromise the maturation of muscle fibers, due to an increase in anti-inflammatory response; however, there is a possible impairment in proinflammatory response and an increase in centralized myonuclei. 相似文献
45.
J. R. Rozisky G. Laste I. C. de Macedo V. S. Santos R. Krolow C. Noschang C. Vanzella K. Bertoldi G. A. Lovatel I. C. C. de Souza I. R. Siqueira C. Dalmaz W. Caumo I. L. S. Torres 《Neurochemical research》2013,38(3):494-503
It is know that repeated exposure to opiates impairs spatial learning and memory and that the hippocampus has important neuromodulatory effects after drug exposure and withdrawal symptoms. Thus, the aim of this investigation was to assess hippocampal levels of BDNF, oxidative stress markers associated with cell viability, and TNF-α in the short, medium and long term after repeated morphine treatment in early life. Newborn male Wistar rats received subcutaneous injections of morphine (morphine group) or saline (control group), 5 μg in the mid-scapular area, starting on postnatal day 8 (P8), once daily for 7 days, and neurochemical parameters were assessed in the hippocampus on postnatal days 16 (P16), 30 (P30), and 60 (P60). For the first time, we observed that morphine treatment in early life modulates BDNF levels in the medium and long term and also modulates superoxide dismutase activity in the long term. In addition, it was observed effect of treatment and age in TNF-α levels, and no effects in lactate dehydrogenase levels, or cell viability. These findings show that repeated morphine treatment in the neonatal period can lead to long-lasting neurochemical changes in the hippocampus of male rats, and indicate the importance of cellular and intracellular adaptations in the hippocampus after early-life opioid exposure to tolerance, withdrawal and addiction. 相似文献
46.
Eldamária de Vargas Wolfgramm Lyvia Neves Rebello Alves Elaine Stur Thaís Tristão Tovar Mariana Penha De Nadai Sartori Allan Kardec de Castro Neto Iúri Drumond Louro 《Molecular biology reports》2013,40(3):2139-2144
Breast cancer is a heterogeneous disease, previously associated with genomic instability. Our aim was to analyze microsatellite markers in order to determine patterns and levels of instability, as well as possible correlations with histopathological parameters. Polymerase chain reaction was used to characterize microsatellite instability (MSI) and loss of heterozygosity (LOH) in 107 breast carcinomas at twelve microsatellite loci. Some of the markers were selected because of their relation to steroid hormone metabolism, which seems to be related to sporadic breast cancer risk. D5S346 and D17S250 markers showed a statistically significant frequency of MSI. LOH in D3S1611, D17S250, AR and ER-β were associated with some parameters of worse prognosis. Marker group analysis showed that CYP19, AR and ER-β were related to histological grade III, ER-negative and PR-negative cases. Our results suggest that marker group analysis may be preferred to the single marker strategy, being predictive of worst prognosis when single markers are unable to provide such information. A further evaluation of steroid metabolism genes and their association with low penetrance genes in breast cancer may be useful. 相似文献
47.
Roberto Montanhini Neto Thayzi O. Zeni Sandra Ludwig Aline Horodesky Marcus V.F. Girotto Gisele G. Castilho-Westphal 《Invertebrate reproduction & development.》2013,57(3):208-218
The production of oysters in Guaratuba Bay, in the state of Paraná, Brazil, is still a mixed activity of mariculture and extractivism. The sustainable development of this production requires the monitoring of environmental, genetic, reproductive, and zootechnical variables. This study evaluated the importance of these variables on Crassostrea oyster production. Data were obtained between September 2009 and February 2011 from six evaluations: water quality, oyster larvae in plankton, capture of oyster spat by artificial collectors, molecular identification of collected spat and larvae, continuous evaluation of the reproductive maturity stage of adult oysters, and zootechnical performance achieved by experimental production. Temperature, dissolved oxygen, and water transparency were the environmental factors that had the most influence on the reproductive cycle (e.g. gonadal development and spat capture) and on the growth of the oyster. The highest rates for spat uptake were recorded in the summer, coinciding with the peak of sexual maturity of adults. The growth of the oysters, in terms of the weight of the meat, was related to the gonadal stage. 相似文献
48.
49.
Arthur F.V.F. Reis Igor L.P. Gonçalves Abel F.G. Neto Alberdan S. Santos Kamil Kuca Eugenie Nepovimova 《Journal of biomolecular structure & dynamics》2013,31(12):3047-3057
In this work, we carried out a theoretical investigation regarding amphetamine-type stimulants, which can cause central nervous system degeneration, interacting with human DNA. These include amphetamine, methamphetamine, 3,4-Methylenedioxymethamphetamine (also known as ecstasy), as well as their main metabolites. The studies were performed through molecular docking and molecular dynamics simulations, where molecular interactions of the receptor–ligand systems, along with their physical–chemical energies, were reported. Our results show that 3,4-Methylenedioxymethamphetamine and 3,4-Dihydroxymethamphetamine (ecstasy) present considerable reactivity with the receptor (DNA), suggesting that these molecules may cause damage due to human-DNA. These results were indicated by free Gibbs change of bind (ΔGbind) values referring to intermolecular interactions between the drugs and the minor grooves of DNA, which were predominant for all simulations. In addition, it was observed that 3,4-Dihydroxymethamphetamine (ΔGbind = ?13.15 kcal/mol) presented greater spontaneity in establishing interactions with DNA in comparison to 3,4-Methylenedioxymethamphetamine (ΔGbind = ?8.61 kcal/mol). Thus, according with the calculations performed our results suggest that the 3,4-Methylenedioxymethamphetamine and 3,4-Dihydroxymethamphetamine have greater probability to provide damage to human DNA fragments. 相似文献
50.
Keller Ricardo Ferreira Sobrinho Ana Carolina Monteiro Santini Carlos Leonardo Sacomani Marques Maicon Gonçalves Gabriel Eduardo de Moura Neto Luciane Aparecida Pascucci Sande de Souza 《Somatosensory & motor research》2013,30(3-4):199-203
AbstractBackground: Unilateral spatial neglect (USN) is the prevalent feature in patients with right-sided stroke. It is diagnosed through the behavior inattention test (BIT) and has a negative impact on patients affecting both their functional capacity and quality of life.Objective: Here, we aimed to evaluate the impact of USN on the quality of life of patients in the chronic phase of stroke.Methods: This is a cross-sectional study with stroke patients with USN. After confirming the presence of stroke through neuroimaging examinations and of USN through the BIT, patients’ quality of life was evaluated by using the EUROQOL scale. Spearman’s correlation was used to validate the correlation between patients’ USN and quality of life, with a p?<?.05 representing significant results.Results: Eighteen individuals were included. When correlating the value of each domain of the EUROQOL scale with the results of the BIT, we observed a negative correlation between mobility (r?=?–0.97; p?=?.000), self-care (r?=?–0.82; p?=?.013), usual activities (r?=?–0.87; p?=?.005); pain or discomfort (r?=?–0.88; p?=?.004), anxiety or depression (r?=?–0.97; p?=?.000), and EUROQOL total score (r?=?–0.97, p?=?.000).Conclusion: After a correlation between the overall EUROQOL and BIT scores, we suggest that the higher the USN degree is in stroke patients, the worse their perceived quality of life tends to be. 相似文献