1,613 research outputs found

    Nitric oxide decreases intestinal haemorrhagic lesions in rat anaphylaxis independently of mast cell activation

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    The purpose of this study is to assess the role of nitric oxide (NO) in the intestinal lesions of passive anaphylaxis, since this experimental model resembles necrotizing enterocolitis. Sprague-Dawley rats were sensitized with IgE anti-dinitrophenol monoclonal antibody. Extravasation of protein-rich plasma and haemorrhagia were measured in the small intestine. Plasma histamine was measured to assess mast cell activation. The effect of exogenous NO on the lesions was assessed by using two structurally unrelated NO-donors: sodium nitroprusside and S-nitroso-Nacetyl-penicillamine (SNAP). An increased basal production of NO was observed in cells taken after anaphylaxis, associated with a reduced response to platelet-activating factor, interleukin 1beta, and IgE/DNP-bovine serum albumin complexes. The response to bacterial lipopolysaccharide and dibutyryl cyclic adenosine monophosphate (AMP) was enhanced 24 h after challenge, but at earlier times was not significantly different from that observed in controls. Treatment with either sodium nitroprusside or SNAP produced a significant reduction of the haemorrhagic lesions, which are a hallmark of rat anaphylaxis. The extravasation of protein-rich plasma was not influenced by NO-donors. The increase of plasma histamine elicited by the anaphylactic challenge was not influenced by SNAP treatment. NO-donors protect intestinal haemorrhagic lesions of rat anaphylaxis by a mechanism apparently independent of mast cell histamine release

    Detecção de Faces em Imagens baseada na Identificação da Pele e dos Olhos

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    Uma das principais áreas de desenvolvimento do domínio da Visão Computacional é a da detecção de faces em imagens. Das várias metodologias existentes nesta área, apresentam-se duas neste artigo: uma baseada na detecção de zonas de pele e uma segunda baseada num modelo protótipo deformável para detecção dos olhos e extracção das suas características. A detecção de zonas de pele permite segmentar imagens de faces considerando regiões nas quais os valores dos seus pixéis, em termos de probabilidade, se assemelham aos exibidos pela pele. No entanto, como esta metodologia não produz informação suficiente para concluir um processo de detecção de faces em imagens com elevada confiança, usa-se em complemento um modelo protótipo deformável para os olhos, que adequadamente posicionado próximo de pequenas regiões detectadas no interior dos segmentos previamente identificados como associados a pele, permite detectar a presença dos olhos e consequentemente validar ou não a existência de uma face. Este artigo apresenta a descrição das referidas metodologias e de alguns resultados experimentais obtidos a partir de implementações desenvolvidas em Matlab

    Study of in vitro and in vivo extraction of kavalactones of pharmaceutical form containing ground plant drug (Piper methysticum G. Forster)

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    An evaluation of the extraction of pharmacological markers (kavalactones) of the plant species Piper methysticum (kava-kava) was conducted. Capsules containing ground kava-kava were submitted to an in vitro method using a controlled dissolution system where the extractive mediums were a solution of 0.1M HCl, phosphate buffered solution (pH = 6.8) and distilled water, at 30 and 60 min, and in vivo that was based on the pylorus ligation method in rats. In the in vitro system starting from 6 capsules (3 g) containing the kava-kava powder, the following extractive concentrations of kavalactones were obtained: HCl (30 min.) = 0.93% (27.9 mg), HCl (60 min.) = 1.1% (33 mg), buff. (30 min) = 2.8% (84 mg), buff. (60 min.) = 0.7% (21 mg), water (30 min.) = 0.71% (21.3 mg) and water (60 min.) = 2.6% (78 mg), while in the in vivo method, 1 and 2 h after administration of 500 mg of the kava-kava powder through gavage, the extractive concentrations of total kavalactones were: 1h = 1.31% (6.55 mg) and 2h = 1.41 % (7.05 mg). In the in vitro system a slight difference was observed among the solutions, which were not statistically significant, and the same occurred with the in vivo experiment, although at the time of 2 h after administration it proved more effective in the extraction of kavalactones by the gastric juice, but below the dose recommended for therapeutic use.Colegio de Farmacéuticos de la Provincia de Buenos Aire

    Study of in vitro and in vivo extraction of kavalactones of pharmaceutical form containing ground plant drug (Piper methysticum G. Forster)

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    An evaluation of the extraction of pharmacological markers (kavalactones) of the plant species Piper methysticum (kava-kava) was conducted. Capsules containing ground kava-kava were submitted to an in vitro method using a controlled dissolution system where the extractive mediums were a solution of 0.1M HCl, phosphate buffered solution (pH = 6.8) and distilled water, at 30 and 60 min, and in vivo that was based on the pylorus ligation method in rats. In the in vitro system starting from 6 capsules (3 g) containing the kava-kava powder, the following extractive concentrations of kavalactones were obtained: HCl (30 min.) = 0.93% (27.9 mg), HCl (60 min.) = 1.1% (33 mg), buff. (30 min) = 2.8% (84 mg), buff. (60 min.) = 0.7% (21 mg), water (30 min.) = 0.71% (21.3 mg) and water (60 min.) = 2.6% (78 mg), while in the in vivo method, 1 and 2 h after administration of 500 mg of the kava-kava powder through gavage, the extractive concentrations of total kavalactones were: 1h = 1.31% (6.55 mg) and 2h = 1.41 % (7.05 mg). In the in vitro system a slight difference was observed among the solutions, which were not statistically significant, and the same occurred with the in vivo experiment, although at the time of 2 h after administration it proved more effective in the extraction of kavalactones by the gastric juice, but below the dose recommended for therapeutic use.Colegio de Farmacéuticos de la Provincia de Buenos Aire

    Development of Ag/TiO2NM-treated leathers with antibacterial activity for footwear industry

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    This work aims to contribute to the industrial development of safer and advanced leathers using nanomaterials (NMs) that are based in titanium oxide doped with silver (Ag-TiO2NMs). These NMs present an ecological alternative to volatile organic biocides and organic solvents, frequently used nowadays. Safe application of these NMs brings added value to footwear and leather products and reduces the bulk chemical wide pollution. These newly developed materials are expected to be useful for footwear manufacturing (for common or professional use) with advanced protection against bacteria and fungus, which are the most common cause of feet infections, for either common or professional use. Hence, the main aim of this work is the improvement of leather footwear in order to overcome the feet infections and ensure minimum risk of human skin penetration. In order to accomplish the main aim, the cytotoxicity, antimicrobial and self-cleaning properties of leather surface, treated with Ag-TiO2NMs by sputtering deposition were assessed. The Ag-TiO2 coatings were deposited onto leather substrates by DC-pulsed reactive magnetron sputtering using two targets, Ti and Ag, in an Ar + O2 atmosphere. Compositional analysis was achieved by X-ray energy dispersive spectrometry (EDX). Contact angle of the coatings was measured and the results show that with the introduction of silver in TiO2 microstructure promotea an increase in hydrophobicity. The antibacterial activity of the samples was assessed by agar diffusion method and the results point out to a silver antibacterial activity

    Urgent-Start Peritoneal Dialysis – a viable option? A case report and literature review

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    Background: Many patients with end -stage renal disease start renal replacement therapy in an unplanned manner. The vast majority initiate hemodialysis by a central venous catheter, since its use is more widespread and available. This technique is associated with a high risk of infection and damage of the vascular patrimony associated with the use of central veins. Urgent -start peritoneal dialysis comes as an alternative treatment for selected patients. Case report: A 55 -year -old woman with focal segmental glomerulosclerosis presented with a rapid decline of renal function and was given renal replacement therapy counselling and opted for peritoneal dialysis. Her chosen modality was postponed for one month due to early uremic symptoms, followed by hemodialysis start through a central venous catheter. During this period a sepsis due to central venous catheter infection occurred, implying four weeks of intravenous antibiotics. Discussion and Conclusion: Although there has been an increase in the number of publications on urgent -start peritoneal dialysis, showing that this technique has comparable results either to urgent -start hemodialysis and planned -start peritoneal dialysis, there still is some resistance to the use of this modality. Given the importance of this subject, this review aims to describe and summarize the available evidence on urgent -start peritoneal dialysis outcomes. Moreover, specific barriers are addressed. Its use is encouraged in hospitals where peritoneal dialysis is available, as an opportunity to improve chronic kidney disease patient management and transition to dialysis.info:eu-repo/semantics/publishedVersio
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