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1.
Acta cir. bras ; 34(11): e201901101, Nov. 2019. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1054681

RESUMO

Abstract Purpose: To determine the efficacy of norbixin-based poly(hydroxybutyrate) (PHB) membranes for Achilles tendon repair. Methods: Thirty rats were submitted to total tenotomy surgery of the right Achilles tendon and divided into two groups (control and membrane; n = 15 each), which were further subdivided into three subgroups (days 7, 14, and 21; n = 5 each). Samples were analyzed histologically. Results: Histological analysis showed a significant reduction in inflammatory infiltrates on days 7, 14 (p < 0.0001 for both), and 21 (p = 0.0004) in the membrane group compared to that in the control group. There was also a significant decrease in the number of fibroblasts in the control group on days 7, 14 (p < 0.0001), and 21 (p = 0.0032). Further, an increase in type I collagen deposition was observed in the membrane group compared to that in the control group on days 7 (p = 0.0133) and 14 (p = 0.0107). Conclusion: Treatment with norbixin-based PHB membranes reduces the inflammatory response, increases fibroblast proliferation, and improves collagen production in the tendon repair region, especially between days 7 and 14.


Assuntos
Humanos , Animais , Masculino , Poliésteres/farmacologia , Tendão do Calcâneo/cirurgia , Tendão do Calcâneo/efeitos dos fármacos , Carotenoides/farmacologia , Tenotomia/métodos , Hidroxibutiratos/farmacologia , Valores de Referência , Regeneração/efeitos dos fármacos , Tendão do Calcâneo/patologia , Reprodutibilidade dos Testes , Ratos Wistar , Colágeno Tipo I/análise , Colágeno Tipo I/efeitos dos fármacos , Colágeno Tipo III/análise , Colágeno Tipo III/efeitos dos fármacos , Fibroblastos/efeitos dos fármacos
2.
Braz. j. med. biol. res ; 50(1): e5492, 2017. graf
Artigo em Inglês | LILACS | ID: biblio-839240

RESUMO

The conventional method for quantification of polyhydroxyalkanoates based on whole-cell methanolysis and gas chromatography (GC) is laborious and time-consuming. In this work, a method based on flow cytometry of Nile red stained bacterial cells was established to quantify poly-3-hydroxybutyrate (PHB) production by the diazotrophic and plant-associated bacteria, Herbaspirillum seropedicae and Azospirillum brasilense. The method consists of three steps: i) cell permeabilization, ii) Nile red staining, and iii) analysis by flow cytometry. The method was optimized step-by-step and can be carried out in less than 5 min. The final results indicated a high correlation coefficient (R2=0.99) compared to a standard method based on methanolysis and GC. This method was successfully applied to the quantification of PHB in epiphytic bacteria isolated from rice roots.


Assuntos
Azospirillum brasilense/metabolismo , Citometria de Fluxo/métodos , Herbaspirillum/metabolismo , Hidroxibutiratos/metabolismo , Raízes de Plantas/microbiologia , Poliésteres/metabolismo , Microscopia de Fluorescência
3.
Artigo em Espanhol | LILACS | ID: lil-728070

RESUMO

El presente texto hace un breve recorrido sobre los usos terapéuticos que han tenido la LSD, MDMA, THC, GHB, DMT, Psilocybina y Mescalina en la historia, así como también refiere algunos de los beneficios para la salud física y mental que se considera tienen en la actualidad. Esta información científica se contrapone a la normativa internacional en materia de drogas, que las clasifica como sustancias prohibidas en la Lista I, debido a su falta de uso médico aceptado por Estados Unidos y a su alto potencial de abuso. En este trayecto también se intenta comprender a qué hace referencia dicho potencial, así como las motivaciones que podrían existir detrás de la prohibición del uso terapéutico de estas drogas. En este marco, se consideran consecuencias para la salud de la población, las que atentan contra los Derechos Humanos de las personas que podrían requerir alguna de estas sustancias.


This paper makes a brief of the therapeutic uses have had the LSD, MDMA, THC, GHB, DMT, Psilocybin and Mescaline in history, as well as some of the benefits referred to physical and mental health that are considered today. This scientific information seems contrary to international legislation on drugs, which classifies as prohibited substances in Schedule I, due to its lack of acceptance medical use by the United States and its high potential for abuse. In this way also try to understand what makes this potential reference, and the reasons that could be behind the ban on therapeutic use of these drugs. In this framework, we consider health consequences of the population, which violate the human rights of people who may require some of these substances.


Assuntos
Humanos , Alucinógenos/uso terapêutico , Psicotrópicos/uso terapêutico , Drogas Ilícitas , Dietilamida do Ácido Lisérgico/uso terapêutico , Dronabinol/uso terapêutico , Direitos Humanos , Hidroxibutiratos/uso terapêutico , Mescalina/uso terapêutico , N,N-Dimetiltriptamina/uso terapêutico , /uso terapêutico , Psilocibina/uso terapêutico
4.
Arq. bras. med. vet. zootec ; 62(5): 1128-1134, out. 2010. ilus
Artigo em Português | LILACS | ID: lil-570471

RESUMO

Avaliou-se o compósito de poli-hidroxibutirado (PHB) 70 por cento e hidroxiapatita (HA) 30 por cento na forma de placas para fixação óssea em gatos. Foram usadas placas do compósito com 60mm de comprimento por 10mm de largura e espessura variando de 3mm no centro a 5mm nas extremidades, com seis orifícios. A placa do compósito foi empregada na fixação de osteotomia de fêmur em quatro gatos, totalizando seis intervenções. Verificou-se a ruptura de cinco placas (83,3 por cento) até o quarto dia e de uma placa (16,7 por cento) aos 21 dias, quando se observou um calo ósseo exuberante. O resultado da implantação da placa no gato mostrou que o compósito não possui resistência suficiente para ser empregado como placas de fixação de fêmur em gatos.


The composite of polyhydroxybutyrate (PHB) 70 percent and hydroxyapatite (HA) 30 percent was evaluated as plate for bone fixation in cats. The employed composite plates presented six orifices and measured 60 x 10mm, length and width, respectively, with thickness ranging from 3 to 5mm according to the region. The composite plate was used in the fixation of femoral osteotomy in four cats, in a total of six interventions. There were ruptures in five plates (83.3 percent) until day 4 and in one plate (16.7 percent) on the day 21, when it was possible to observe an exuberant osseous callus. The result of the plate deployment in the cat showed that the composite does not have sufficient strength to be used as plate of femoral fixation in cats.


Assuntos
Animais , Gatos , Fixação de Fratura/veterinária , Materiais Biocompatíveis/uso terapêutico , Gatos , Durapatita , Hidroxibutiratos
5.
Electron. j. biotechnol ; 11(3): 95-101, July 2008. graf
Artigo em Inglês | LILACS | ID: lil-531889

RESUMO

The effect of sequencing batch reactor (SBR) operating conditions on sludge macromolecular composition and the effect of sludge macromolecular composition on the anaerobic degradation of the sludge produced in SBR was investigated in this work. A SBR, fed with synthetic wastewater, was operated at different air flow rates. The resulting sludge was analyzed in terms of protein, carbohydrate, phospholipid and polyhydroxybutyrate concentrations. Methane production during anaerobic digestion of the sludge was also measured. Ammonium, nitrite, nitrate, dissolved oxygen and chemical oxygen demand (COD) track studies in the SBR were carried out in order to relate SBR performance and sludge macromolecular composition. The lowest air flow rate at which the SBR was operated was 2 l min-1, in which case the dissolved oxygen concentration was lower than 0.5 mg l-1 in the SBR and partial denitrification occurred during the feeding phase. An increased air flow rate caused a decrease in protein concentration, as well as an increase in carbohydrate concentration. Polyhydroxybutyrate (PHB) concentration in the sludge was independent of air flow rate. At different air flows, the methane production rates were similar, but the total volume of methane was greater during anaerobic digestion of the sludge produced at low air flow rates. These results indicate a strategy by which changes in sludge composition can optimize the operation of anaerobic sludge digesters.


Assuntos
Águas Residuárias/análise , Águas Residuárias/química , Digestão Anaeróbia/análise , Degradação de Resíduos Químicos , Carbono/química , Hidroxibutiratos/análise , Nitrogênio/química , Reatores Biológicos Sequenciais/métodos
6.
Electron. j. biotechnol ; 11(3): 83-94, July 2008. ilus, graf, tab
Artigo em Inglês | LILACS | ID: lil-531890

RESUMO

Three halotolerant bacterial strains; Rhodobacter sphaeroides ES16 (the wild type) and the two mutant strains of R. sphaeroides ES16, namely N20 and U7, were cultivated in glutamate-malate (GM) medium and screened for production of polyhydroxybutyrate (PHB). The mutant strains N20 and U7 were found to accumulate PHB (53.9 and 42.0 percent of DCW, respectively) 3.6 and 2.8 times higher than the wild type strain (19.5 percent of DCW), respectively. R. sphaeroides N20 were selected for studies on the effects of nutrient and environmental conditions on PHB accumulation. The optimal condition was 4 g/l acetate, 0.02 g/l (NH4)2SO4, C/N ratio of 6:1, 1.0 g/l K2HPO4, 1.0 g/l KH2PO4 and 3 percent NaCl with initial pH at 7.0. Under this optimal condition, the maximum PHB accumulation increased from 53.9 percent to 88 percent of DCW and 9.11 ± 0.08 g/l biomass, 8.02 +/- 0.10 g/l PHB concentration were achieved after 60 hrs cultivation at 37ºC. These results are the highest values ever obtained from photosynthetic bacteria reported so far.


Assuntos
Bactérias Gram-Negativas Fotossintetizantes Oxigênicas , Hidroxibutiratos , Rhodobacter sphaeroides/enzimologia , Rhodobacter sphaeroides/metabolismo , Cromatografia Gasosa , Fermentação , Microscopia Eletrônica de Transmissão , Nitrogênio/administração & dosagem
7.
Braz. j. med. biol. res ; 38(11): 1623-1632, Nov. 2005. ilus
Artigo em Inglês | LILACS | ID: lil-414714

RESUMO

Vero cells, a cell line established from the kidney of the African green monkey (Cercopithecus aethiops), were cultured in F-10 Ham medium supplemented with 10 percent fetal calf serum at 37°C on membranes of poly(L-lactic acid) (PLLA), poly(hydroxybutyrate-co-hydroxyvalerate) (PHBV) and their blends in different proportions (100/0, 60/40, 50/50, 40/60, and 0/100). The present study evaluated morphology of cells grown on different polymeric substrates after 24 h of culture by scanning electron microscopy. Cell adhesion was also analyzed after 2 h of inoculation. For cell growth evaluation, the cells were maintained in culture for 48, 120, 240, and 360 h. For cytochemical study, the cells were cultured for 120 or 240 h, fixed, processed for histological analysis, and stained with Toluidine blue, pH 4.0, and Xylidine ponceau, pH 2.5. Our results showed that cell adhesion was better when 60/40 and 50/50 blends were used although cells were able to grow and proliferate on all blends tested. When using PLLA/PHBV (50/50) slightly flattened cells were observed on porous and smooth areas. PLLA/PHBV (40/60) blends presented flattened cells on smooth areas. PLLA/PHBV (0/100), which presented no pores, also supported spreading cells interconnected by thin filaments. Histological sections showed that cells grew as a confluent monolayer on different substrates. Cytochemical analysis showed basophilic cells, indicating a large amount of RNA and proteins. Hence, we detected changes in cell morphology induced by alterations in blend proportions. This suggests that the cells changed their differentiation pattern when on various PLLA/PHBV blend surfaces.


Assuntos
Animais , Materiais Biocompatíveis , Células Vero/citologia , Hidroxibutiratos , Ácido Láctico , Membranas Artificiais , Polímeros , Técnicas de Cultura de Células/métodos , Adesão Celular/fisiologia , Chlorocebus aethiops , Células Vero/ultraestrutura , Histocitoquímica , Microscopia Eletrônica de Varredura , Porosidade
8.
Braz. j. med. biol. res ; 34(5): 627-631, May 2001. ilus
Artigo em Inglês | LILACS | ID: lil-285878

RESUMO

2-Hydroxybutyric acid appears at high concentrations in situations related to deficient energy metabolism (e.g., birth asphyxia) and also in inherited metabolic diseases affecting the central nervous system during neonatal development, such as "cerebral" lactic acidosis, glutaric aciduria type II, dihydrolipoyl dehydrogenase (E3) deficiency, and propionic acidemia. The present study was carried out to determine the effect of 2-hydroxybutyric acid at various concentrations (1-10 mM) on CO2 production and lipid synthesis from labeled substrates in cerebral cortex of 30-day-old Wistar rats in vitro. CO2 production was significantly inhibited (30-70 percent) by 2-hydroxybutyric acid in cerebral cortex prisms, in total homogenates and in the mitochondrial fraction. We also demonstrated a significant inhibition of lipid synthesis (20-45 percent) in cerebral cortex prisms and total homogenates in the presence of 2-hydroxybutyric acid. However, no inhibition of lipid synthesis occurred in homogenates free of nuclei and mitochondria. The results indicate an impairment of mitochondrial energy metabolism caused by 2-hydroxybutyric acid, a fact that may secondarily lead to reduction of lipid synthesis. It is possible that these findings may be associated with the neuropathophysiology of the situations where 2-hydroxybutyric acid is accumulated


Assuntos
Animais , Ratos , Dióxido de Carbono/metabolismo , Córtex Cerebral/efeitos dos fármacos , Metabolismo Energético , Hidroxibutiratos/farmacologia , Lipídeos/síntese química , Análise de Variância , Hidroxibutiratos/química , Mitocôndrias/metabolismo , Ratos Wistar
9.
Rev. argent. microbiol ; 23(1): 26-9, ene.-feb. 1991. ilus, tab
Artigo em Espanhol | LILACS | ID: lil-117770

RESUMO

La centrifugación en gradientes de sacarosa permite la separación de células según su densidad boyante de acuerdo al contenido en poli-ß-hidroxibutirato (PHB). En este trabajo este método se evaluó y se adaptó para detectar mutantes deficientes en la síntesis de PHB de B. megaterium analizando un bajo porcentaje de la población mutagenizada


Assuntos
Bacillus megaterium/genética , Hidroxibutiratos/metabolismo , Poliésteres/metabolismo , Bacillus megaterium/isolamento & purificação , Bacillus megaterium/metabolismo , Centrifugação com Gradiente de Concentração , Esporos Bacterianos
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