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41.
Ricardo Moreira Borges Samuel Santos Valença Alan Aguiar Lopes Nancy dos Santos Barbi Antonio Jorge Ribeiro da Silva 《Phytochemistry letters》2013,6(1):96-100
Five triterpenoidal saponins were isolated from the roots of Chiococca alba (L.) Hitchc. (Rubiaceae). Two of the saponins, chiococcasaponin III (3-O-β-d-glucopyranurosyl-3β-hydroxyolean-12,15-dien-28-oic acid 28-O-β-d-xylopyranosyl (1 → 4)-α-l-rhamnopyranosyl (1 → 2)-α-l-arabinopyranosyl ester) and chiococcasaponin IV (3-O-β-d-glucopyranurosyl-3β-hydroxyolean-12,15-dien-28-oic acid 28-O-α-l-rhamnopyranosyl (1 → 2)-α-l-arabinopyranosyl ester) were new and their structures were elucidated on the basis of extensive application of NMR techniques and high resolution electrospray mass spectrometry together with acid hydrolysis product analysis. As part of our investigations on the chemical profile and pharmacological activity of the roots of C. alba, we report the results of the evaluation of the activity of the saponin fractions against in vitro lipopolysaccharide-induced inflammation. The results found, strongly support the fractions I, III and IV as having anti-inflammatory properties. 相似文献
42.
Fabrícia F. Nascimento Ana Lazar Albert N. Menezes Andressa da Matta Durans Janio C. Moreira Jorge Salazar-Bravo Paulo S. D′Andrea Cibele R. Bonvicino 《PloS one》2013,8(4)
The Neotropics harbors a high diversity of species and several hypotheses have been proposed to account for this pattern. However, while species of forested domains are frequently studied, less is known of species from open vegetation formations occupying, altogether, a larger area than the Amazon Forest. Here we evaluate the role of historical barriers and the riverine hypothesis in the speciation patterns of small mammals by analyzing an ancient rodent lineage (Thrichomys, Hystricomorpha). Phylogenetic and biogeographic analyses were carried out with mitochondrial and nuclear DNA markers to analyze the evolutionary relationships between Thrichomys lineages occurring in dry domains along both banks of the Rio São Francisco. This river is one of the longest of South America whose course and water flow have been modified by inland tectonic activities and climate changes. Molecular data showed a higher number of lineages than previously described. The T. inermis species complex with 2n = 26, FN = 48 was observed in both banks of the river showing a paraphyletic arrangement, suggesting that river crossing had occurred, from east to west. A similar pattern was also observed for the T. apereoides complex. Thrichomys speciation occurred in Late Miocene when the river followed a different course. The current geographic distribution of Thrichomys species and their phylogenetic relationships suggested the existence of frequent past connections between both banks in the middle section of the Rio São Francisco. The extensive palaeodune region found in this area has been identified as a centre of endemism of several vertebrate species and is likely to be a center of Thrichomys diversification. 相似文献
43.
Beatriz Grinsztejn Paula M. Luz Antonio G. Pacheco Desiree V. G. Santos Luciane Velasque Ronaldo I. Moreira Maria Regina C. Guimar?es Estev?o P. Nunes Alberto S. Lemos Sayonara R. Ribeiro Dayse P. Campos Marco A. A. Vitoria Valdilea G. Veloso 《PloS one》2013,8(4)
Introduction
We describe temporal trends in the mortality rates and factors associated with AIDS and non-AIDS related mortality at the Evandro Chagas Clinical Research Institute (IPEC), Oswaldo Cruz Foundation (FIOCRUZ).Methods
Adult patients enrolling from 1986 through 2009 with a minimum follow up of 60 days were included. Vital status was exhaustively checked using patients’ medical charts, through active contact with individuals and family members and by linkage with the Rio de Janeiro Mortality database using a previously validated algorithm. The CoDe protocol was used to establish the cause of death. Extended Cox proportional hazards models were used for multivariate modeling.Results
A total of 3530 individuals met the inclusion criteria, out of which 868 (24.6%) deceased; median follow up per patient was 3.9 years (interquartile range 1.7–9.2 years). The dramatic decrease in the overall mortality rates was driven by AIDS-related causes that decreased from 9.19 deaths/100PYs n 1986–1991 to 1.35/100PYs in 2007–2009. Non-AIDS related mortality rates remained stable overtime, at around 1 death/100PYs. Immunodeficiency significantly increased the hazard of both AIDS-related and non-AIDS-related causes of death, while HAART use was strongly associated with a lower hazard of death from either cause.Conclusions
Our results confirm the remarkable decrease in AIDS-related mortality as the HIV epidemic evolved and alerts to the conditions not traditionally related to HIV/AIDS which are now becoming more frequent, needing careful monitoring. 相似文献44.
da Silva-Carvalho Lidiane Maria Genovez-Oliveira Jhon Lennon de Souza Oliveira Mariana de Oliveira Águida Aparecida de Lima Viviane Moreira Ferreira Ildemar Berto Bruno Pereira 《Systematic parasitology》2020,97(6):847-855
Systematic Parasitology - Isospora parnaitatiaiensis Silva, Rodrigues, Lopes, Berto, Luz, Ferreira & Lopes, 2015 was identified from a new host, the plain antvireo Dysithamnus mentalis... 相似文献
45.
Anton Débora Bublitz Guzman Frank Lino Vetö Nicole Moreira Krause Felipe Augusto Kulcheski Franceli Rodrigues Coelho Ana Paula Durand Duarte Guilherme Leitão Margis Rogério Dillenburg Lúcia Rebello Turchetto-Zolet Andreia Carina 《Molecular biology reports》2020,47(2):1033-1043
Molecular Biology Reports - Eugenia uniflora is an Atlantic Forest native species, occurring in contrasting edaphoclimatic environments. The identification of genes involved in response to abiotic... 相似文献
46.
Nuno A. Silva Joana Moreira Silvina Ribeiro-Samy Eduardo D. Gomes Roger Y. Tam Molly S. Shoichet Rui L. Reis Nuno Sousa António J. Salgado 《Biochimie》2013
It has been demonstrated that bone marrow mesenchymal stem cell (BM-MSCs) transplantation has beneficial effects on several central nervous system (CNS) debilitating conditions. Growing evidence indicate that trophic factors secreted by these cells are the key mechanism by which they are acting. These cells are frequently used in combination with 3D artificial matrices, for instance hydrogels, in tissue engineering-based approaches. However, so far, no study has been reported on the influence of such matrices, namely the presence or absence of extracellular matrix motifs, on BM-MSCs secretome and its effects in neuronal cell populations. In this sense, we herein studied the impact of a hydrogel, gellan gum, on the behavior and secretome of BM-MSCs, both in its commercial available form (commonly used in tissue engineering) and in a fibronectin peptide-modified form. The results showed that in the presence of a peptide in the gellan gum hydrogel, BM-MSCs presented higher proliferation and metabolic activity than in the regular hydrogel. Moreover, the typical spindle shape morphology of BM-MSCs was only observed in the modified hydrogel. The effects of the secretome of BM-MSCs were also affected by the chemical nature of the extracellular matrix. BM-MSCs cultured in the modified hydrogel were able to secrete factors that induced higher metabolic viabilities and neuronal cell densities, when compared to those of the unmodified hydrogel. Thus adding a peptide sequence to the gellan gum had a significant effect on the morphology, activity, proliferation and secretome of BM-MSCs. These results highlight the importance of mimicking the extracellular matrix when BM-MSCs are cultured in hydrogels for CNS applications. 相似文献
47.
Daniela M. Santos Maria M. M. Santos Rui Moreira Susana Solá Cecília M. P. Rodrigues 《Molecular neurobiology》2013,47(1):313-324
Naphthoquinones are bioactive compounds widespread in nature that impact on several cellular pathways, including cell proliferation and survival, by acting as prooxidants and electrophiles. We have previously described the role of the synthetic isoxazole condensed 1,4-naphthoquinone derivative 1a in preventing apoptosis induced by distinct stimuli in several cell models. In addition, apoptosis regulators and executioners may control neural stem cell (NSC) fate, without involving cell death per se. Here, we hypothesize that 1a might also play a role in NSC fate decision. We found that exposure to 1a shifts NSC differentiation potential from neurogenic to gliogenic lineage and involves the generation of reactive oxygen species, without increasing cell death. Modulation of caspases and calpains, using cysteine protease inhibitors, failed to mimic 1a effects. In addition, incubation with the naphthoquinone derivative resulted in upregulation and nuclear translocation of antioxidant responsive proteins, Nrf2 and Sirt1, which in turn may mediate 1a-directed shift in NSC differentiation. In fact, antioxidants halted the shift in NSC differentiation potential from neurogenic to gliogenic lineage, while strongly reducing reactive oxygen species generation and Nrf2 and Sirt1 nuclear translocation in NSC exposed to 1a. Collectively, these data support a new role for a specific naphthoquinone derivative in NSC fate decision and underline the importance of redox environment control. 相似文献
48.
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
49.
Hemiodus iratapuru, a new species of the Hemiodontidae from the Rio Iratapuru, a left bank tributary of the Rio Jari, Amazon Basin, Brazil, is described. The new species is diagnosed from other species of Hemiodus by modifications in the ectopterygoid, tooth form, scale counts, dorsal‐fin form and colour pattern. The new species is proposed to be related to the Hemiodus quadrimaculatus species group. 相似文献
50.
Andrea C. Paula‐Lima Jordano Brito‐Moreira Sergio T. Ferreira 《Journal of neurochemistry》2013,126(2):191-202
Alzheimer′s disease (AD) is the most common form of dementia in the elderly. Memory loss in AD is increasingly attributed to soluble oligomers of the amyloid‐β peptide (AβOs), toxins that accumulate in AD brains and target particular synapses. Glutamate receptors appear to be centrally involved in synaptic targeting by AβOs. Once bound to neurons, AβOs dysregulate the activity and reduce the surface expression of both N‐methyl‐d ‐aspartate (NMDA) and 2‐amino‐3‐(3‐hydroxy‐5‐methyl‐isoxazol‐4‐yl)propanoic acid (AMPA) types of glutamate receptors, impairing signaling pathways involved in synaptic plasticity. In the extracellular milieu, AβOs promote accumulation of the excitatory amino acids, glutamate and d ‐serine. This leads to overactivation of glutamate receptors, triggering abnormal calcium signals with noxious impacts on neurons. Here, we review key findings linking AβOs to deregulated glutamate neurotransmission and implicating this as a primary mechanism of synapse failure in AD. We also discuss strategies to counteract the impact of AβOs on excitatory neurotransmission. In particular, we review evidence showing that inducing neuronal hyperpolarization via activation of inhibitory GABAA receptors prevents AβO‐induced excitotoxicity, suggesting that this could comprise a possible therapeutic approach in AD. 相似文献