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1.
Open Biol ; 13(5): 230049, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-37161288

RESUMO

Nutrient scarcity is a frequent adverse condition that organisms face during their development. This condition may lead to long-lasting effects on the metabolism and behaviour of adults due to developmental epigenetic modifications. Here, we show that reducing nutrient availability during larval development affects adult spontaneous activity and sleep behaviour, together with changes in gene expression and epigenetic marks in the mushroom bodies (MBs). We found that open chromatin regions map to 100 of 241 transcriptionally upregulated genes in the adult MBs, these new opening zones are preferentially located in regulatory zones such as promoter-TSS and introns. Importantly, opened chromatin at the Dopamine 1-like receptor 2 regulatory zones correlate with increased expression. In consequence, adult administration of a dopamine antagonist reverses increased spontaneous activity and diminished sleep time observed in response to early-life nutrient restriction. In comparison, reducing dop1R2 expression in MBs also ameliorates these effects, albeit to a lesser degree. These results lead to the conclusion that increased dopamine signalling in the MBs of flies reared in a poor nutritional environment underlies the behavioural changes observed due to this condition during development.


Assuntos
Dopamina , Drosophila , Animais , Drosophila/genética , Larva/genética , Dieta , Encéfalo , Cromatina/genética , Epigênese Genética , Nutrientes
2.
Mater Lett ; 311: 131554, 2022 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-34963705

RESUMO

COVID-19 pandemic created a global shortage of medical protective equipment. Here, we considered ozone (O3) a disinfectant alternative due to its potent oxidative activity against biological macromolecules. The O3 decontamination assays were done using SARS-CoV-2 obtained from patients to produce artificial contamination of N95 masks and biosecurity gowns. The quantification of SARS-CoV-2 was performed before and after exposing the samples to different ozone gas concentrations for times between 5 and 30 min. Viral loads as a function of the O3 exposure time were estimated from the data obtained by the RT-PCR technique. The genetic material of the virus was no longer detected for any tested concentrations after 15 min of O3 exposure, which means a disinfection Concentration-Time above 144 ppm min. Vibrational spectroscopies were used to follow the modifications of the polymeric fibers after the O3 treatment. The results indicate that the N95 masks could be safely reused after decontamination with treatments of 15 min at the established O3 doses for a maximum of 6 cycles.

3.
Mar Environ Res ; 161: 105135, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32942210

RESUMO

Environmental changes have been associated with natural climatic variability or human activity. Water resources management is, perhaps, the most drastic change observed in the coastal environment. However, external forcings such as the El Niño event have important implications in the global and regional hydrological balance. These environmental changes have an impact on the density and biomass of the ichthyofauna in the Terminos Lagoon (TL) for the past 30 years, presumably, associated with variations in the temperature and surface salinity of the sea. Therefore, in the present study, δ18O was quantified in otoliths of two important species due to their dominance: Stellifer lanceolatus and Eucinostomus gula, and to understand the environmental changes reflected in both species. The δ18O was analyzed in otoliths of these two species captured in 1998/1997, 2006/2007 and 2016/2017 and were compared with in situ temperature and salinity data. Sea surface temperature and salinity increased by 2 °C and 9, respectively, between 1997 and 2017. Stellifer lanceolatus δ18O values was in isotopic equilibrium with seawater calcite; while, E. gula is not in isotopic equilibrium. The δ18O of S. lanceolatus and E. gula varied significantly with the increase in salinity (R2 = 0.8987 and R2 = -0.2964) and not with the sea surface temperature. S. lanceolatus is an excellent bioindicator of changes in sea surface salinity in this region of the Gulf of Mexico.


Assuntos
Membrana dos Otólitos , Água do Mar , Animais , Golfo do México , Humanos , México , Salinidade
4.
Lancet ; 393(10190): 2503-2510, Jun. 2019. tabela, gráfico
Artigo em Inglês | Sec. Est. Saúde SP, SESSP-IDPCPROD, Sec. Est. Saúde SP | ID: biblio-1046380

RESUMO

Background New-generation drug-eluting stents (DES) have mostly been investigated in head-to-head non-inferiority trials against early-generation DES and have typically shown similar efficacy and superior safety. How the safety profile of new-generation DES compares with that of bare-metal stents (BMS) is less clear.Methods We did an individual patient data meta-analysis of randomized clinical trials to compare outcomes after implantation of new-generation DES or BMS among patients undergoing percutaneous coronary intervention. The primary outcome was the composite of cardiac death or myocardial infarction. Data were pooled in a one-stage random-effects meta-analysis and examined at maximum follow-up and a 1-year landmark. Risk estimates are reported as hazard ratios (HRs) with 95% CIs. This study is registered in PROSPERO, number CRD42017060520.Findings We obtained individual data for 26 616 patients in 20 randomized trials. Mean follow-up was 3·2 (SD 1·8) years. The risk of the primary outcome was reduced in DES recipients compared with BMS recipients (HR 0·84, 95% CI 0·78­0·90, p<0·001) owing to a reduced risk of myocardial infarction (0·79, 0·71­0·88, p<0·001) and a possible slight but non-significant cardiac mortality benefit (0·89, 0·78­1·01, p=0·075). All-cause death was unaffected (HR with DES 0·96, 95% CI 0·88­1·05, p=0·358), but risk was lowered for definite stent thrombosis (0·63, 0·50­0·80, p<0·001) and target-vessel revascularization (0·55, 0·50­0·60, p<0·001). We saw a time-dependent treatment effect, with DES being associated with lower risk of the primary outcome than BMS up to 1 year after placement. While the effect was maintained in the longer term, there was no further divergence from BMS after 1 year. Interpretation The performance of new-generation DES in the first year after implantation means that BMS should no longer be considered the gold standard for safety. Further development of DES technology should target improvements in clinical outcomes beyond 1 year. (AU)


Assuntos
Angioplastia Coronária com Balão , Stents Metálicos Autoexpansíveis
5.
Trop Anim Health Prod ; 51(1): 243-248, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29934796

RESUMO

Mycoplasma ovis is a small, pleiotropic bacterium, which parasitizes the external surface of erythrocytes of several species of artiodactyl mammals, especially sheep and goats. We here report an outbreak of ovine mycoplasmosis in a sheep flock of a private ranch (Universidad Veracruzana) in Veracruz, Mexico. For the identification of Mycoplasma and other hemoparasitic bacterial agents, we stained blood smears with the DiffQuick® technique and additionally amplified several fragments of 16S rDNA gene. We detected the presence of morulas in erythrocytes from 30 sick female adult sheep, and found Mycoplasma ovis DNA in all of them. Furthermore, three of these animals also tested positive for Anaplasma ovis. Our findings represent the first record of M. ovis and A. ovis in an outbreak of hemolytic anemia in a sheep flock, leading to severe livestock loss in a ranch of Mexico. This study highlights the importance of establishing an active surveillance of both pathogens in the country.


Assuntos
Anemia Hemolítica/veterinária , Infecções por Mycoplasma/veterinária , Mycoplasma/isolamento & purificação , Doenças dos Ovinos/microbiologia , Anaplasma ovis/isolamento & purificação , Anemia Hemolítica/epidemiologia , Anemia Hemolítica/microbiologia , Animais , Surtos de Doenças/veterinária , Eritrócitos , Feminino , Gado , México , Mycoplasma/genética , Infecções por Mycoplasma/epidemiologia , Ovinos , Doenças dos Ovinos/epidemiologia
6.
Bull Environ Contam Toxicol ; 100(3): 395-401, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29299634

RESUMO

A molecularly imprinted polymer was developed and evaluated for selective determination of metronidazole (MNZ) in wastewater. This was achieved by using sodium methacrylate as monomer, toluene as porogen, ethylene glycol dimethacrylate as crosslinker, azobisisobutyronitrile as initiator and metronidazole as template molecule to generate the selectivity of the polymer for the compound, as well as non-imprinted polymers were synthesized. Two different polymerization approaches were used, bulk and emulsion and the polymers obtained by emulsion presented higher retention percentages the MIP 2-M presented the higher retention (83%). The performed method, was validated in fortified water, showing linearity from 10 up to 1000 ng/mL; limit of detection and quantification for compound were between 3 and 10 ng/mL, respectively. Finally, the method was applied in samples of a wastewater treatment plant in the city of San Luis Potosí, México, and the concentrations of MNZ in these samples were 84.1-114 ng/mL.


Assuntos
Metronidazol/análise , Impressão Molecular/métodos , Ácidos Polimetacrílicos/síntese química , Águas Residuárias/química , Poluentes Químicos da Água/análise , Adsorção , Limite de Detecção , Metacrilatos/química , México , Nitrilas/química , Ácidos Polimetacrílicos/química , Propriedades de Superfície , Tolueno/química
7.
Toxicol In Vitro ; 29(4): 657-62, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25681759

RESUMO

Single-walled carbon nanotubes (SWCNTs) are used in biological systems with impact in biomedicine in order to improve diagnostics and treatment of diseases. However, their effects upon the vascular system, are not fully understood. Endothelium and smooth muscle cells (SMC) communicate through release of vasoactive factors as nitric oxide (NO) to maintain vascular tone. The aim of this study was to evaluate the effect of SWCNTs on vascular tone using isolated rat aortic rings, which were exposed to SWCNTs (0.1, 1 and 10 µg/mL) in presence and absence of endothelium. SWCNTs induced vasodilation in both conditions, indicating that this effect was independent on endothelium; moreover that vasodilation was NO-independent, since its blockage with L-NAME did not modify the observed effect. Together, these results indicate that SWCNTs induce vasodilation in the macrovasculature, may be through a direct interaction with SMC rather than endothelium independent of NO production. Further investigation is required to fully understand the mechanisms of action and mediators involved in the signaling pathway induced by SWCNTs on the vascular system.


Assuntos
Nanotubos de Carbono/toxicidade , Vasodilatação/efeitos dos fármacos , Animais , Aorta Torácica/efeitos dos fármacos , Endotélio Vascular/fisiologia , Técnicas In Vitro , Masculino , Tono Muscular/efeitos dos fármacos , Músculo Liso Vascular/efeitos dos fármacos , Óxido Nítrico/metabolismo , Ratos , Ratos Wistar
8.
Comput Math Methods Med ; 2013: 909625, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24198850

RESUMO

This paper presents a new unsupervised image segmentation method based on particle swarm optimization and scaled active contours with shape prior. The proposed method uses particle swarm optimization over a polar coordinate system to perform the segmentation task, increasing the searching capability on medical images with respect to different interactive segmentation techniques. This method is used to segment the human heart and ventricular areas from datasets of computed tomography and magnetic resonance images, where the shape prior is acquired by cardiologists, and it is utilized as the initial active contour. Moreover, to assess the performance of the cardiac medical image segmentations obtained by the proposed method and by the interactive techniques regarding the regions delineated by experts, a set of validation metrics has been adopted. The experimental results are promising and suggest that the proposed method is capable of segmenting human heart and ventricular areas accurately, which can significantly help cardiologists in clinical decision support.


Assuntos
Algoritmos , Coração/anatomia & histologia , Coração/diagnóstico por imagem , Modelos Cardiovasculares , Reconhecimento Automatizado de Padrão/estatística & dados numéricos , Inteligência Artificial , Sistemas de Apoio a Decisões Clínicas , Humanos , Imageamento por Ressonância Magnética/estatística & dados numéricos , Modelos Estatísticos , Interpretação de Imagem Radiográfica Assistida por Computador/métodos , Tomografia Computadorizada por Raios X/estatística & dados numéricos
9.
Biochimie ; 95(10): 1871-9, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23806421

RESUMO

Ribosome biogenesis is a pre-requisite for cell growth and proliferation; it is however, a highly regulated process that consumes a great quantity of energy. It requires the coordinated production of rRNA, ribosomal proteins and non-ribosomal factors which participate in the processing and mobilization of the new ribosomes. Ribosome biogenesis has been studied in yeast and animals; however, there is little information about this process in plants. The objective of the present work was to study ribosome biogenesis in maize seeds during germination, a stage characterized for its fast growth, and the effect of insulin in this process. Insulin has been reported to accelerate germination and to induce seedling growth. It was observed that among the first events reactivated just after 3 h of imbibition are the rDNA transcription and the pre-rRNA processing and that insulin stimulates both of them (40-230%). The transcript of nucleolin, a protein which regulates rDNA transcription and pre-rRNA processing, is among the messages stored in quiescent dry seeds and it is mobilized into the polysomal fraction during the first hours of imbibition (6 h). In contrast, de novo ribosomal protein synthesis was low during the first hours of imbibition (3 and 6 h) increasing by 60 times in later stages (24 h). Insulin increased this synthesis (75%) at 24 h of imbibition; however, not all ribosomal proteins were similarly regulated. In this regard, an increase in RPS6 and RPL7 protein levels was observed, whereas RPL3 protein levels did not change even though its transcription was induced. Results show that ribosome biogenesis in the first stages of imbibition is carried out with newly synthesized rRNA and ribosomal proteins translated from stored mRNA.


Assuntos
DNA Ribossômico/genética , Regulação da Expressão Gênica de Plantas , Germinação/genética , Ribossomos/genética , Sementes/genética , Zea mays/genética , DNA Ribossômico/metabolismo , Regulação da Expressão Gênica no Desenvolvimento , Insulina/farmacologia , Fosfoproteínas/genética , Fosfoproteínas/metabolismo , Processamento Pós-Transcricional do RNA , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Proteínas de Ligação a RNA/genética , Proteínas de Ligação a RNA/metabolismo , Proteínas Ribossômicas/genética , Proteínas Ribossômicas/metabolismo , Ribossomos/efeitos dos fármacos , Ribossomos/metabolismo , Sementes/efeitos dos fármacos , Sementes/crescimento & desenvolvimento , Sementes/metabolismo , Fatores de Tempo , Transcrição Gênica , Zea mays/efeitos dos fármacos , Zea mays/crescimento & desenvolvimento , Zea mays/metabolismo , Nucleolina
10.
Comput Math Methods Med ; 2013: 132953, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23762177

RESUMO

This paper presents a novel image segmentation method based on multiple active contours driven by particle swarm optimization (MACPSO). The proposed method uses particle swarm optimization over a polar coordinate system to increase the energy-minimizing capability with respect to the traditional active contour model. In the first stage, to evaluate the robustness of the proposed method, a set of synthetic images containing objects with several concavities and Gaussian noise is presented. Subsequently, MACPSO is used to segment the human heart and the human left ventricle from datasets of sequential computed tomography and magnetic resonance images, respectively. Finally, to assess the performance of the medical image segmentations with respect to regions outlined by experts and by the graph cut method objectively and quantifiably, a set of distance and similarity metrics has been adopted. The experimental results demonstrate that MACPSO outperforms the traditional active contour model in terms of segmentation accuracy and stability.


Assuntos
Coração/anatomia & histologia , Interpretação de Imagem Assistida por Computador/métodos , Modelos Cardiovasculares , Biologia Computacional , Bases de Dados Factuais , Coração/diagnóstico por imagem , Ventrículos do Coração/anatomia & histologia , Ventrículos do Coração/diagnóstico por imagem , Humanos , Imageamento por Ressonância Magnética/estatística & dados numéricos , Interpretação de Imagem Radiográfica Assistida por Computador/métodos , Tomografia Computadorizada por Raios X/estatística & dados numéricos
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