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11.
Juliane Pereira-Ribeiro Thais Linause Átilla C. Ferreguetti Jonathan Cozer Helena G. Bergallo Carlos Frederico D. Rocha 《Austral ecology》2023,48(7):1405-1412
Stream-dwelling amphibians' occurrence, behaviour and reproductive success are strongly influenced by dynamic abiotic factors, for example, water flow and spray. These factors can disproportionately affect these frogs due to their dependency on specific favourable conditions for development and incapacity to disperse from unfavourable environments. We analysed the influence of environmental covariates on the detectability of Crossodactylus gaudichaudii, an amphibian species endemic to streams in the Brazilian Atlantic Forest. We conducted sampling in the streams of the Duas Bocas Biological Reserve, Brazil, and we measured air and water temperature, air humidity and pH of water on each sampling occasion. We estimated the effects of variables on the detectability of the species using single-season occupancy models. Our results indicated that the detectability of the species increases on occasions with higher water temperatures (24–26°C) and lower pH (5.0–5.5). We investigated the influence of these covariates only on the detectability of adult frogs, but it is likely that the physiochemical properties of stream water are more important to aquatic larvae, and hence, the probability of their detection. Given this, further studies should examine the relevance of covariates on the detectability of adult frogs as well as larvae. 相似文献
12.
Coordinated and distinct roles for IFN-alpha beta,IL-12, and IL-15 regulation of NK cell responses to viral infection 总被引:13,自引:0,他引:13
Nguyen KB Salazar-Mather TP Dalod MY Van Deusen JB Wei XQ Liew FY Caligiuri MA Durbin JE Biron CA 《Journal of immunology (Baltimore, Md. : 1950)》2002,169(8):4279-4287
NK cell cytotoxicity, IFN-gamma expression, proliferation, and accumulation are rapidly induced after murine CMV infections. Under these conditions, the responses were shown to be elicited in overlapping populations. Nevertheless, there were distinct signaling molecule requirements for induction of functions within the subsets. IL-12/STAT4 was critical for NK cell IFN-gamma expression, whereas IFN-alphabeta/STAT1 were required for induction of cytotoxicity. The accumulation/survival of proliferating NK cells was STAT4-independent but required IFN-alphabeta/STAT1 induction of IL-15. Taken together, the results define the coordinated interactions between the cytokines IFN-alphabeta, IL-12, and IL-15 for activation of protective NK cell responses during viral infections, and emphasize these factors' nonredundant functions under in vivo physiological conditions. 相似文献
13.
Maurício dos Santos Pereira Matheus Figueiredo Sathler Thais da Rosa Valli Richard Souza Marques Ana Lucia Marques Ventura Ney Ronner Peccinalli Mabel Carneiro Fraga Alex C. Manh?es Regina Kubrusly 《PloS one》2015,10(10)
Methylphenidate (MPD) is one of the most prescribed drugs for alleviating the symptoms of Attention Deficit/Hyperactivity Disorder (ADHD). However, changes in the molecular mechanisms related to MPD withdrawal and susceptibility to consumption of other psychostimulants in normal individuals or individuals with ADHD phenotype are not completely understood. The aims of the present study were: (i) to characterize the molecular differences in the prefrontal dopaminergic system of SHR and Wistar strains, (ii) to establish the neurochemical consequences of short- (24 hours) and long-term (10 days) MPD withdrawal after a subchronic treatment (30 days) with Ritalin® (Methylphenidate Hydrochloride; 2.5 mg/kg orally), (iii) to investigate the dopaminergic synaptic functionality after a cocaine challenge in adult MPD-withdrawn SHR and Wistar rats. Our results indicate that SHR rats present reduced [3H]-Dopamine uptake and cAMP accumulation in the prefrontal cortex (PFC) and are not responsive to dopaminergic stimuli in when compared to Wistar rats. After a 24-hour withdrawal of MPD, SHR did not present any alterations in [3H]-Dopamine Uptake, [3H]-SCH 23390 binding and cAMP production; nonetheless, after a 10-day MPD withdrawal, the results showed a significant increase of [3H]-Dopamine uptake, of the quantity of [3H]-SCH 23390 binding sites and of cAMP levels in these animals. Finally, SHR that underwent a 10-day MPD withdrawal and were challenged with cocaine (10 mg/kg i.p.) presented reduced [3H]-Dopamine uptake and increased cAMP production. Wistar rats were affected by the 10-day withdrawal of MPD in [3H]-dopamine uptake but not in cAMP accumulation; in addition, cocaine was unable to induce significant modifications in [3H]-dopamine uptake and in cAMP levels after the 10-day withdrawal of MPD. These results indicate a mechanism that could explain the high comorbidity between ADHD adolescent patients under methylphenidate treatment and substance abuse in adult life. 相似文献
14.
Yanqin Ren Szu Han Huang Amanda B. Macedo Adam R. Ward Winiffer D. Conce Alberto Thais Klevorn Louise Leyre Dennis C. Copertino Talia M. Mota Dora Chan Ronald Truong Thomas Rohwetter Paul Zumbo Friederike Dündar Doron Betel Colin Kovacs Erika Benko Alberto Bosque R. Brad Jones 《Journal of virology》2021,95(15)
15.
Katiucia Batista Silva Paiva Willian Fernando Zambuzzi Thais Accorsi-Mendonça Rumio Taga Fabio Daumas Nunes Mari Cleide Sogayar José Mauro Granjeiro 《Journal of molecular histology》2009,40(3):201-207
Reversion-inducing-cysteine-rich protein with Kazal motifs (RECK) is a single membrane-anchored MMP-regulator and regulates
matrix metalloproteinases (MMP) 2, 9 and 14. In turn, MMPs are endopeptidases that play a pivotal role in remodeling ECM.
In this work, we decided to evaluate expression pattern of RECK in growing rat incisor during, specifically focusing out amelogenesis
process. Based on different kinds of ameloblasts, our results showed that RECK expression was conducted by secretory and post-secretory
ameloblasts. At the secretory phase, RECK was localized in the infra-nuclear region of the ameloblast, outer epithelium, near
blood vessels, and in the stellate reticulum. From the transition to the maturation phases, RECK was strongly expressed by
non-epithelial immuno-competent cells (macrophages and/or dendritic-like cells) in the papillary layer. From the transition
to the maturation stage, RECK expression was increased. RECK mRNA was amplified by RT-PCR from whole enamel organ. Here, we
verified the presence of RECK mRNA during all stages of amelogenesis. These events were governed by ameloblasts and by non-epithelial
cells residents in the enamel organ. Concluding, we found differential expression of MMPs-2, -9 and RECK in the different
phases of amelogenesis, suggesting that the tissue remodeling is rigorously controlled during dental mineralization. 相似文献
16.
Rodrigo Araújo Lima Rodrigues Ludmila Karen dos Santos Silva Fábio Pio Dornas Danilo Bretas de Oliveira Thais Furtado Ferreira Magalh?es Daniel Assis Santos Adriana Oliveira Costa Luiz de Macêdo Farias Paula Prazeres Magalh?es Cláudio Ant?nio Bonjardim Erna Geessien Kroon Bernard La Scola Juliana Reis Cortines J?natas Santos Abrah?o 《Journal of virology》2015,89(23):11812-11819
17.
Yvonne Nussbaumer-Ochsner Jan Stolk Luiz F. Ferraz da Silva Annemarie van Schadewijk Ronald C. de Jeu Frans A. Prins Thais Mauad Klaus F. Rabe Pieter S. Hiemstra 《PloS one》2015,10(6)
Background
Smoking is associated with a mixed inflammatory infiltrate in the airways. We evaluated whether airway inflammation in smokers is related to lung function parameters and inflammatory markers in exhaled breath.Methods
Thirty-seven smokers undergoing lung resection for primary lung cancer were assessed pre-operatively by lung function testing including single-breath-nitrogen washout test (sb-N2-test), measurement of fractional exhaled nitric oxide (FeNO) and pH/8-isoprostane in exhaled breath condensate (EBC). Lung tissue sections containing cancer-free large (LA) and small airways (SA) were stained for inflammatory cells. Mucosal (MCT) respectively connective tissue mast cells (MCTC) and interleukin-17A (IL-17A) expression by mast cells was analysed using a double-staining protocol.Results
The median number of neutrophils, macrophages and mast cells infiltrating the lamina propria and adventitia of SA was higher than in LA. Both MCTC and MCT were higher in the lamina propria of SA compared to LA (MCTC: 49 vs. 27.4 cells/mm2; MCT: 162.5 vs. 35.4 cells/mm2; P<0.005 for both instances). IL-17A expression was predominantly detected in MCTC of LA. Significant correlations were found for the slope of phase III % pred. of the sb-N2-test (rs= -0.39), for the FEV1% pred. (rs= 0.37) and for FEV1/FVC ratio (rs=0.38) with MCT in SA (P<0.05 for all instances). 8-isoprostane concentration correlated with the mast cells in the SA (rs=0.44), there was no correlation for pH or FeNO with cellular distribution in SA.Conclusions
Neutrophils, macrophages and mast cells are more prominent in the SA indicating that these cells are involved in the development of small airway dysfunction in smokers. Among these cell types, the best correlation was found for mast cells with lung function parameters and inflammatory markers in exhaled breath. Furthermore, the observed predominant expression of IL-17A in mast cells warrants further investigation to elucidate their role in smoking-induced lung injury, despite the lack of correlation with lung function and exhaled breath parameters. 相似文献18.
Henrique Barbosa Thais A. Costa-Silva Geanne A. Alves Conserva Adelson J. Araujo Ana Luísa L. Lordello Guilherme M. Antar Maiara Amaral Marisi G. Soares Andre G. Tempone João Henrique G. Lago 《化学与生物多样性》2021,18(4):e2001022
One new aporphine, dicentrine-β-N-oxide ( 1 ), together with five related known alkaloids dehydrodicentrine ( 2 ), predicentrine ( 3 ), N-methyllaurotetanine ( 4 ), cassythicine ( 5 ), and dicentrine ( 6 ) were isolated from the leaves of Ocotea puberula (Lauraceae). Antiprotozoal activity of the isolated compounds was evaluated in vitro against trypomastigote forms of Trypanosoma cruzi. Among the tested compounds, alkaloid 1 exhibited higher potential with EC50 value of 18.2 μM and reduced toxicity against NCTC cells (CC50>200 μM – SI>11.0), similar to positive control benznidazole (EC50 of 17.7 μM and SI=10.7). Considering the promising results of dicentrine-β-N-oxide ( 1 ) against trypomastigotes, the mechanism of parasite death caused by this alkaloid was investigated. As observed, this compound reached the plasma membrane electric potential directly after 2 h of incubation and triggered mitochondrial depolarization, which probably leads to trypomastigote death. Therefore, dicentrine-β-N-oxide ( 1 ), reported for the first time in this work, can contribute to future works for the development of new trypanocidal agents. 相似文献
19.
Solange S. Samarão Carlos E.S. Teodoro Flavia E. Silva Camila C. Ribeiro Thais M. Granato Cláudio A. Retamal Anna L. Okorokova-Façanha 《生物化学与生物物理学报:生物膜》2009,1788(2):303-313
H+ transport driven by V H+-ATPase was found in membrane fractions enriched with ER/PM and Golgi/Golgi-like membranes of Saccharomyces cerevisiae efficiently purified in sucrose density gradient from the vacuolar membranes according to the determination of the respective markers including vacuolar Ca2+-ATPase, Pmc1::HA. Purification of ER from PM by a removal of PM modified with concanavalin A reduced H+ transport activity of P H+-ATPase by more than 75% while that of V H+-ATPase remained unchanged. ER H+ ATPase exhibits higher resistance to bafilomycin (I50 = 38.4 nM) than Golgi and vacuole pumps (I50 = 0.18 nM). The ratio between a coupling efficiency of the pumps in ER, membranes heavier than ER, vacuoles and Golgi is 1.0, 2.1, 8.5 and 14 with the highest coupling in the Golgi. The comparative analysis of the initial velocities of H+ transport mediated by V H+-ATPases in the ER, Golgi and vacuole membrane vesicles, and immunoreactivity of the catalytic subunit A and regulatory subunit B further supported the conclusion that V H+-ATPase is the intrinsic enzyme of the yeast ER and Golgi and likely presented by distinct forms and/or selectively regulated. 相似文献
20.
Ants in their plants: Pseudomyrmex ants reduce primate,parrot and squirrel predation on Macrolobium acaciifolium (Fabaceae) seeds in Amazonian Brazil 下载免费PDF全文
Adrian A. Barnett Thais Almeida Richelly Andrade Sarah Boyle Marcelo Gonçalves de Lima Ann MacLarnon Caroline Ross Welma Sousa Silva Wilson R. Spironello Beatriz Ronchi‐Teles 《Biological journal of the Linnean Society. Linnean Society of London》2015,114(2):260-273
Although plant‐inhabiting ants are known to act as effective deterrents to a variety of vertebrate and invertebrate herbivores, this has been reported only once before for primates, a group better known for their predation of ants. In the present study, we investigated the effects that colonies of Pseudomyrmex viduus ants living in individual Macrolobium acaciifolium (Fabaceae) trees have on the rates of visitation and fruit removal by four taxa of seed‐predating vertebrates: the primate Cacajao melanocephalus ouakary; macaws (Ara spp.); large parrots (Amazona spp.); and the Northern Amazonian red squirrel (Sciurus igniventris). We found that ant presence significantly reduced both rates of visitation and of fruit removal by C. m. ouakary. The same pattern of reduced fruit removal was also observed for other seed predators (parrots, macaws, and squirrels) but not for visitation rates (although this may be a result of the small sample size). This appears to be only the second‐known demonstration of the repellent effect of ants on primates and, indeed, the first for squirrels and psittacine birds. © 2014 The Linnean Society of London, Biological Journal of the Linnean Society, 2015, 114 , 260–273. 相似文献