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1.
Interv Neuroradiol ; : 15910199231153195, 2023 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-36751025

RESUMO

BACKGROUND AND AIMS: Endovascular treatment for cerebrovascular disease is accepted as a first-line option with level I evidence in patients with an early and late time of window of onset symptoms, and an additional option in patients who do not respond or with contraindications to systemic thrombolysis; nevertheless the efficacy and outcomes of some groups were not clear, one of them are patients aged 80 years and older, because they were excluded of the trials, so the evidence is controversial with significant heterogeneity, for that reason in our study, we decided to analyze the age in the patients treated in our stroke center, as a predictor of prognosis, and to provide a baseline for the establishment of personalized treatment plans. METHODS: Observational, retrospective study of patients that received endovascular treatment for cerebrovascular disease in a Colombian stroke center between 2016 and 2020, continuous and categorical variables were compared using the Student's t test and Chi-Square. To determine cut-off points in the variable against death and Rankin score variable on 90th day. RESULTS: In total, 108 patients were recruited, 35 of them were of 80 or more years, and the mean age was 72.7 years, we found age as a significant variable to predict the risk in the population over 80 years of age [RR 3.37 CI (95% 1.14-103) p = 0.029]. CONCLUSIONS: Age younger than 80 is a significant predictor for results and long-term outcomes in patients suffering from stroke, and in patients older than 80 years old a Thrombolysis in Cerebral Infarction score 2b-3 is a predictor of good outcomes. Further studies are needed to evaluate the relationship between intrahospital complications and long-term outcomes.

2.
An Acad Bras Cienc ; 91(4): e20181337, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31800703

RESUMO

What controls the formation of patchy substrates of white sand vegetation in the Amazonian lowlands is still unclear. This research integrated the geological history and plant inventories of a white sand vegetation patch confined to one large fan-shaped sandy substrate of northern Amazonia, which is related to a megafan environment. We examined floristic patterns to determine whether abundant species are more often generalists than the rarer one, by comparing the megafan environments and older basement rocks. We also investigated the pattern of species accumulation as a function of increasing sampling effort. All plant groups recorded a high proportion of generalist species on the megafan sediments compared to older basement rocks. The vegetation structure is controlled by topographic gradients resulting from the smooth slope of the megafan morphology and microreliefs imposed by various megafan subenvironments. Late Pleistocene-Holocene environmental disturbances caused by megafan sedimentary processes controlled the distribution of white sand vegetation over a large area of the Amazonian lowlands, and may have also been an important factor in species diversification during this period. The integration of geological and biological data may shed new light on the existence of many patches of white sand vegetation from the plains of northern Amazonia.


Assuntos
Sedimentos Geológicos , Fenômenos Geológicos , Melastomataceae , Traqueófitas , Brasil , Geografia , Areia
3.
ACS Omega ; 4(2): 3660-3672, 2019 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-31459579

RESUMO

Electroactive and biocompatible fibrous scaffolds have been prepared and characterized using polyaniline (PAni) doped with dodecylbenzenesulfonic acid (DBSA) combined with poly(lactic acid) (PLA) and PLA/poly(ethylene glycol) (PEG) mixtures. The composition of simple and core-shell fibers, which have been obtained by both uniaxial and coaxial electrospinning, respectively, has been corroborated by Fourier-transform infrared and micro-Raman spectroscopies. Morphological studies suggest that the incorporation of PEG enhances the packing of PLA and PAni chains, allowing the regulation of the thickness of the fibers. PAni and PEG affect the thermal and electrical properties of the fibers, both decreasing the glass transition temperature and increasing the electrical conductivity. Interestingly, the incorporation of PEG improves the PAni-containing paths associated with the conduction properties. Although dose response curves evidence the high cytotoxicity of PAni/DBSA, cell adhesion and cell proliferation studies on PLA/PAni fibers show a reduction of such harmful effects as the conducting polymer is mainly retained inside the fibers through favorable PAni···PLA interactions. The incorporation of PEG into uniaxial fibers resulted in an increment of the cell mortality, which has been attributed to its rapid dissolution into the culture medium and the consequent enhancement of PAni release. In opposition, the delivery of PAni decreases and, therefore, the biocompatibility of the fibers increases when a shell coating the PAni-containing system is incorporated through coaxial electrospinning. Finally, morphological and functional studies using cardiac cells indicated that these fibrous scaffolds are suitable for cardiac tissue engineering applications.

4.
Microb Drug Resist ; 22(8): 688-695, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27007167

RESUMO

Stenotrophomonas maltophilia is an emerging nosocomial pathogen responsible for several infections in immunocompromised patients. To characterize the antimicrobial resistance and virulence potential of this microorganism in a Brazilian hospital, a total of 936 samples were collected from a nosocomial environment and medical devices, and 100 isolates from clinical specimens were obtained in the same hospital. S. maltophilia was found in 3% of the samples collected, especially in bed rails from hospital rooms. The smf-1 gene was detected in 23% and 42% of the clinical and hospital environment isolates, respectively, and almost all (96.8%) isolates that harbored smf-1 were able to form biofilm. All isolates were susceptible to minocycline and chloramphenicol, and the majority of isolates were susceptible to levofloxacin. High resistance to ceftazidime was detected in both groups of isolates. Resistance to trimethoprim-sulfamethoxazole (TMP/SMX) was found in 14.8% of the isolates. All TMP/SMX-resistant isolates presented class 1 integron and sul1 gene, and 47.4% of them also harbored the sul2 gene, which was inserted into a 7.3 kb plasmid. Genetic relatedness among the isolates was evaluated by enterobacterial repetitive intergenic consensus-PCR, and eight genetic patterns were identified. One pattern comprised 54.7% of isolates and was spread among clinical and environmental (furniture and medical devices) sources. The presence of S. maltophilia in the hospital environment indicates that it can act as a reservoir of this microorganism. In addition, hospital isolates resistant to TMP/SMX showed that the genetic determinants were present in mobile elements, which can constitute great concern, as it may indicate a tendency to spread.


Assuntos
Infecção Hospitalar/epidemiologia , Regulação Bacteriana da Expressão Gênica , Genes Bacterianos , Infecções por Bactérias Gram-Negativas/epidemiologia , Plasmídeos/metabolismo , Stenotrophomonas maltophilia/genética , Antibacterianos/farmacologia , Técnicas de Tipagem Bacteriana , Biofilmes/efeitos dos fármacos , Biofilmes/crescimento & desenvolvimento , Brasil/epidemiologia , Ceftazidima/farmacologia , Cloranfenicol/farmacologia , Infecção Hospitalar/tratamento farmacológico , Infecção Hospitalar/microbiologia , Farmacorresistência Bacteriana/genética , Fômites/microbiologia , Infecções por Bactérias Gram-Negativas/tratamento farmacológico , Infecções por Bactérias Gram-Negativas/microbiologia , Hospitais , Humanos , Integrons , Levofloxacino/farmacologia , Minociclina/farmacologia , Filogenia , Plasmídeos/química , Reação em Cadeia da Polimerase , Stenotrophomonas maltophilia/classificação , Stenotrophomonas maltophilia/efeitos dos fármacos , Stenotrophomonas maltophilia/isolamento & purificação , Combinação Trimetoprima e Sulfametoxazol/farmacologia
5.
J Dairy Sci ; 99(4): 2617-2624, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26830746

RESUMO

The Bacillus cereus group includes important spore-forming bacteria that present spoilage capability and may cause foodborne diseases. These microorganisms are traditionally evaluated in food using culturing methods, which can be laborious and time-consuming, and may also fail to detect bacteria in a viable but nonculturable state. The purpose of this study was to develop a quantitative real-time PCR (qPCR) combined with a propidium monoazide (PMA) treatment to analyze the contamination of UHT milk by B. cereus group species viable cells. Thirty micrograms per milliliter of PMA was shown to be the most effective concentration for reducing the PCR amplification of extracellular DNA and DNA from dead cells. The quantification limit of the PMA-qPCR assay was 7.5 × 10(2) cfu/mL of milk. One hundred thirty-five UHT milk samples were analyzed to evaluate the association of PMA to qPCR to selectively detect viable cells. The PMA-qPCR was able to detect B. cereus group species in 44 samples (32.6%), whereas qPCR without PMA detected 78 positive samples (57.8%). Therefore, the PMA probably inhibited the amplification of DNA from cells that were killed during UHT processing, which avoided an overestimation of bacterial cells when using qPCR and, thus, did not overvalue potential health risks. A culture-based method was also used to detect and quantify B. cereus sensu stricto in the same samples and showed positive results in 15 (11.1%) samples. The culture method and PMA-qPCR allowed the detection of B. cereus sensu stricto in quantities compatible with the infective dose required to cause foodborne disease in 3 samples, indicating that, depending on the storage conditions, even after UHT treatment, infective doses may be reached in ready-to-consume products.


Assuntos
Azidas/química , Bacillus cereus/fisiologia , Microbiologia de Alimentos/métodos , Leite/microbiologia , Propídio/análogos & derivados , Reação em Cadeia da Polimerase em Tempo Real , Animais , Bacillus cereus/genética , Primers do DNA/genética , Limite de Detecção , Propídio/química , Reprodutibilidade dos Testes
6.
Antonie Van Leeuwenhoek ; 108(5): 1227-38, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26337044

RESUMO

Antimicrobial resistance profiles and presence of resistance determinants and integrons were evaluated in Salmonella enterica strains from Brazilian poultry. The analysis of 203 isolates showed that those from the poultry environment (88 isolates) were significantly more resistant to antimicrobials than isolates from other sources, particularly those isolated from poultry by-product meal (106 isolates). Thirty-seven isolates were resistant to at least three antimicrobial classes. Class 1 integrons were detected in 26 isolates, and the analysis of the variable region between the 5' conserved segment (CS) and 3' CS of each class 1 integron-positive isolate showed that 13 contained a typical 3' CS and 14 contained an atypical 3' CS. One Salmonella Senftenberg isolate harbored two class 1 integrons, showing both typical and atypical 3' CSs. The highest percentage of resistance was found to sulfonamides, and sul genes were detected in the majority of the resistant isolates. Aminoglycoside resistance was detected in 50 isolates, and aadA and aadB were present in 28 and 32 isolates, respectively. In addition, strA and strB were detected in 78.1 and 65.6% isolates resistant to streptomycin, respectively. Twenty-one isolates presented reduced susceptibility to ß-lactams and harbored bla(TEM), bla(CMY), and/or bla(CTX-M). Forty isolates showed reduced susceptibility to tetracycline, and most presented tet genes. These results highlight the importance of the environment as a reservoir of resistant Salmonella, which may enable the persistence of resistance determinants in the poultry production chain, contributing, therefore, to the debate regarding the impacts that antimicrobial use in animal production may exert in human health.


Assuntos
Anti-Infecciosos/farmacologia , Farmacorresistência Bacteriana , Microbiologia de Alimentos , Produtos da Carne/microbiologia , Salmonella enterica/classificação , Salmonella enterica/efeitos dos fármacos , Animais , Brasil , Farmacorresistência Bacteriana/genética , Genes Bacterianos , Integrons , Testes de Sensibilidade Microbiana , Aves Domésticas , Salmonella enterica/genética , Salmonella enterica/isolamento & purificação
7.
J Phys Chem B ; 118(4): 1102-12, 2014 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-24428522

RESUMO

The role of the incorporation of conducting polymer (CP), doped with different sulfonic acid organic molecules, in polystyrene (PS) and high-impact polystyrene (HIPS) with poly(styrene-ethylene-butylene) (SEBS) triblock copolymer has been investigated. Two factors associated with this model membrane system are addressed: (i) the influence of the presence of a low concentration of doped conducting polymer and (ii) the influence of the membrane preparation method. Membrane characterization and bulk conductivity measurements allowed the conclusion that proton conductivity has been promoted by the addition of CP; the best results were achieved for PAni-CSA, in either PS/SEBS or HIPS/SEBS blends. Additionally, the water uptake only decreased with the addition of PAni-doped molecules compared to the pure copolymer, without loss of ion-exchange capacity (IEC). Electrodialysis efficiency for HIPS/SEBS (before annealing) is higher than that for HIPS/SEBS (after annealing), indicating that membrane preparation method is crucial. Finally, through-plane cell arrangement proved to be an effective, quick, and time-saving tool for studying the main resistance parameters of isolating polymers, which is useful for application in industry and research laboratories working with membranes for electrodialysis or fuel cells.

8.
Vet Parasitol ; 197(1-2): 304-11, 2013 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-23906807

RESUMO

Rhipicephalus microplus is a parasite that causes economic losses in cattle herds, and immunological control is the most promising alternative to replace chemical control. The muscular protein paramyosin has been additionally found in non-muscle tissues and characterized as presenting activities that enable the evasion of the host's immune system in various parasites. This report investigated the recognition level of paramyosin by sera of infested bovines, its expression in tissues, organs and different life stages of R. microplus. ELISA analyses showed that paramyosin and salivary gland extract were recognized by infested Bos taurus and B. indicus sera. Paramyosin gene expression was evaluated in egg, larvae, adult male, and several tissues of partially- and fully-engorged females by qRT-PCR, showing the highest expression levels in fat body. These results show that R. microplus paramyosin is immunologically recognized during the tick infestation and together with the high transcription rate found in organs that do not present a highly developed musculature, further suggests that it may possess additional, non-muscle functions in the tick-bovine relationship.


Assuntos
Anticorpos/sangue , Antígenos/metabolismo , Regulação da Expressão Gênica/imunologia , Rhipicephalus/metabolismo , Tropomiosina/imunologia , Animais , Antígenos/imunologia , Bovinos , Doenças dos Bovinos/sangue , Doenças dos Bovinos/imunologia , Feminino , Larva/metabolismo , Masculino , Óvulo/metabolismo , Rhipicephalus/imunologia
9.
J Phys Chem B ; 116(38): 11767-79, 2012 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-22991943

RESUMO

In this study we prepared blends of polystyrene (PS) and high-impact polystyrene (HIPS) with poly(styrene-ethylene-butylene) (SEBS) triblock copolymer. After sulfonation, blends were used to fabricate ion-exchange membranes by solvent-casting and subsequent thermal treatment to obtain homogeneous packing densities. The morphology and structure of the blends were investigated by scanning electron microscopy, atomic force microscopy, and FTIR spectroscopy. Furthermore, the thermal transitions and stability of all the blends were characterized using calorimetric techniques and compared with those of the individual polymers. Analyses of the physical properties (i.e., ionic conductivity, ion-exchange capacity, water uptake, dimensional stability, mechanical properties, etc.) showed that the performance of the PS-containing membranes is, in general, higher than that of the HIPS containing one. Furthermore, the highest sulfonation degree was also found for the PS/SEBS membranes. The capabilities of the membranes were tested by investigating the extraction of Na(+) by electrodyalisis. Comparison of the percentage of extracted ions indicates that the incorporation of SEBS results in a significant improvement with respect to membranes made of individual polymers.


Assuntos
Poliestirenos/química , Purificação da Água , Condutividade Elétrica , Estrutura Molecular , Solubilidade , Temperatura
10.
Anal Biochem ; 428(2): 108-10, 2012 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-22728959

RESUMO

Propidium monoazide (PMA) is a DNA-intercalating agent used to selectively detect DNA from viable cells by polymerase chain reaction (PCR). Here, we report that high concentrations (>5%) of sodium chloride (NaCl) prevents PMA from inhibiting DNA amplification from dead cells. Moreover, Halobacterium salinarum was unable to maintain cell integrity in solutions containing less than 15% NaCl, indicating that extreme halophilic microorganisms may not resist the concentration range in which PMA fully acts. We conclude that NaCl, but not pH, directly affects the efficiency of PMA treatment, limiting its use for cell viability assessment of halophiles and in hypersaline samples.


Assuntos
Azidas/farmacologia , Halobacterium salinarum/citologia , Halobacterium salinarum/efeitos dos fármacos , Viabilidade Microbiana/efeitos dos fármacos , Propídio/análogos & derivados , Cloreto de Sódio/farmacologia , DNA Bacteriano/genética , Genoma Bacteriano/genética , Halobacterium salinarum/genética , Reação em Cadeia da Polimerase , Propídio/farmacologia
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