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1.
Braz. j. biol ; 82: e237386, 2022. graf
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1249227

RESUMO

Shewanella xiamenensis G5-03 was observed to decolorize the azo dye Congo red in synthetic wastewater. The influence of some factors on the dye decolorization efficiency was evaluated. The optimal decolorization conditions were temperature 30-35 °C, pH 10.0, incubation time 10 h, and static condition. The kinetic of Congo red decolorization fitted to the Michaelis­Menten model (Vmax = 111.11 mg L-1 h-1 and Km = 448.3 mg L-1). The bacterium was also able to degrade benzidine, a product of azo bond breakage of the Congo red, which contributed to reduce the phytotoxicity. The ability of S. xiamenensis G5-03 for simultaneous decolorization and degradation of Congo red shows its potential application for the biological treatment of wastewaters containing azo dyes.


Shewanella xiamenensis G5-03 foi capaz de descolorir o corante azo vermelho Congo em água residuária sintética. A influência de alguns fatores na eficiência da descoloração do corante foi avaliada. As condições ótimas de descoloração foram temperatura de 30-35 °C, pH 10,0 e condições estáticas. A cinética de descoloração do vermelho Congo se ajustou ao modelo de Michaelis­Menten (Vmax = 111,11 mg L-1 h-1 and Km = 448,3 mg L-1). A bactéria também foi capaz de degradar a benzidina, um produto da quebra da ligação azo do vermelho Congo, o que contribuiu para a redução da fitotoxicidade. A habilidade da S. xiamenensis G5-03 em simultaneamente descolorir e degradar o vermelho Congo demostra seu potencial de aplicação no tratamento de águas residuárias contendo corantes azo.


Assuntos
Compostos Azo , Vermelho Congo , Benzidinas , Biodegradação Ambiental , Shewanella , Corantes
2.
Electron. j. biotechnol ; 46: 22-29, jul. 2020. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1223226

RESUMO

BACKGROUND: Removal of dyes from wastewater by microorganisms through adsorption, degradation, or accumulation has been investigated. Biological methods used for dye treatment are generally always effective and environmentally friendly. In this study, biosorption of the Fast Black K salt azo dye by the bacterium Rhodopseudomonas palustris 51ATA was studied spectrophotometrically, at various pH (2­10), temperatures (25°C, 35°C, and 45°C) and dye concentrations (25­400 mg L-1). RESULTS: The bacterial strain showed extremely good dye-removing potential at various dye concentrations. IR studies at different temperatures showed that the dye was adsorbed on the bacterial surface at lower temperatures. Characteristics of the adsorption process were investigated by Scatchard analysis at 25°C and 35°C. Scatchard analysis of the equilibrium binding data for the dye on this bacterium gave rise to linear plots, indicating that the Langmuir model could be applied. The regression coefficients obtained for the dye from the Freundlich and Langmuir models were significant and divergence from the Scatchard plot was observed. CONCLUSION: The adsorption behavior of the dye on this bacterium was expressed by the Langmuir, Freundlich, and Temkin isotherms. The adsorption data with respect to various temperatures provided an excellent fit to the Freundlich isotherm. However, when the Langmuir and Temkin isotherm models were applied to these data, a good fit was only obtained for the dye at lower temperatures, thus indicating that the biosorption ability of R. palustris 51ATA is dependent on temperature, pH, and dye concentration.


Assuntos
Rodopseudomonas/metabolismo , Compostos de Diazônio/metabolismo , Corantes/metabolismo , Temperatura , Compostos Azo/análise , Compostos Azo/metabolismo , Remoção de Contaminantes , Adsorção , Corantes/análise , Águas Residuárias , Concentração de Íons de Hidrogênio
3.
Electron. j. biotechnol ; 43: 1-7, Jan. 2020. tab, graf, ilus
Artigo em Inglês | LILACS | ID: biblio-1087520

RESUMO

Background: Textile industry not only plays a vital role in our daily life but also a prominent factor in improving global economy. One of the environmental concern is it releases huge quantities of toxic dyes in the water leading to severe environmental pollution. Bacterial laccase and azoreductase successfully oxidize complex chemical structure of nitrogen group-containing azo dyes. Additionally, the presence of textile dye infuriates bacterial peroxidase to act as a dye degrading enzyme. Our present study deals with three textile dye degrading enzymes laccase, azoreductase, and peroxidase through analyzing their structural and functional properties using standard computational tools. Result: According to the comparative analysis of physicochemical characteristics, it was clear that laccase was mostly made up of basic amino acids whereas azoreductase and peroxidase both comprised of acidic amino acids. Higher aliphatic index ascertained the thermostability of all these three enzymes. Negative GRAVY value of the enzymes confirmed better water interaction of the enzymes. Instability index depicted that compared to laccase and preoxidase, azoreductase was more stable in nature. It was also observed that the three model proteins had more than 90% of total amino acids in the favored region of Ramachandran plot. Functional analysis revealed laccase as multicopper oxidase type enzyme and azoreductase as FMN dependent enzyme, while peroxidase consisted of α-ß barrel with additional haem group. Conclusion: Present study aims to provide knowledge on industrial dye degrading enzymes, choosing the suitable enzyme for industrial set up and to help in understanding the experimental laboratory requirements as well.


Assuntos
Compostos Azo/metabolismo , Peroxidase/química , Lacase/química , NADH NADPH Oxirredutases/química , Temperatura , Compostos Azo/química , Indústria Têxtil , Biodegradação Ambiental , Simulação por Computador , Estabilidade Enzimática , Peroxidase/metabolismo , Lactase/metabolismo , Corantes/metabolismo , NADH NADPH Oxirredutases/metabolismo
4.
Braz. arch. biol. technol ; 63: e20180573, 2020. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1132185

RESUMO

Abstract This work reports the study of the potential application of Zn/TiO2 catalysts, obtained by the sol-gel method, in processes of environmental decontamination through the reactions of photodegradation of textile dye, followed by electrospray mass spectrometry. The catalysts synthesis was performed according to a 2² factorial design with repetition at the central point. The characterization techniques used were: N2 adsorption measurements (BET method), scanning electron microscopy with energy dispersive X-ray (MEV/EDS), X-ray diffraction and point of zero charge (PZC). The photocatalytic tests were performed in batch in the presence of sunlight, and to evaluate the degradation kinetics study, a rapid direct injection electrospray mass spectrometry (DI-ESI-MS) method has been developed. By the photocatalytic tests, the calcination temperature of 400 °C has shown the best results of discoloration for the reactive Orange-122 dye (99.76%) in a reaction time of 2h. The discoloration kinetics were a pseudo-first order, and a statistical analysis was performed to investigate the effects of the variables and to optimize the conditions of discoloration to the dye. After the reactional time of 2 h, an ion of m/z 441.5 was detected by ESI-MS, indicating that the photocatalytic process was effective for the degradation of the dye to secondary compounds.


Assuntos
Compostos Azo/toxicidade , Biodegradação Ambiental , Descontaminação/métodos , Espectrometria de Massas em Tandem/métodos , Recuperação e Remediação Ambiental/métodos , Águas Residuárias , Fotoquímica , Têxteis/toxicidade , Microscopia Eletrônica de Varredura , Catálise , Domínio Catalítico , Espectrometria de Massas por Ionização por Electrospray , Corantes , Fotobiorreatores , Modelos Teóricos
5.
Acta cir. bras ; 34(5): e201900504, 2019. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1010871

RESUMO

Abstract Purpose: To establish a new rat model, the pathogenesis of which is closer to the clinical occurrence of chronic obstructive jaundice with liver fibrosis. Methods: 90 SD rats were randomly divided into 3 groups. Group A common bile duct ligation, group B common bile duct injection compont and group C injection saline. The serum of three groups was extracted, and the liver function was detected by ELISA. HE staining, Masson staining and immunohistochemistry were used to detect liver pathology. Results: Group B showed a fluctuant development of jaundice, obstructive degree reached a peak at 2 weeks, and decreased from 3 weeks. HA, LA and PCIII were significantly higher than control group. 3 weeks after surgery, liver tissue fibrosis occurred in group B, and a wide range of fiber spacing was formed at 5 weeks. Immunohistochemistry showed that hepatic stellate cells were more active than the control group. Conclusion: Intra-biliary injection of Compont gel is different from the classic obstructive jaundice animal model caused by classic bile duct ligation, which can provide an ideal rat model of chronic obstructive jaundice with liver fibrosis.


Assuntos
Animais , Feminino , Ductos Biliares/efeitos dos fármacos , Modelos Animais de Doenças , Géis/administração & dosagem , Cirrose Hepática/induzido quimicamente , Aspartato Aminotransferases/sangue , Valores de Referência , Compostos Azo , Fatores de Tempo , Ductos Biliares/patologia , Bilirrubina/análise , Albumina Sérica/análise , Ensaio de Imunoadsorção Enzimática , Imuno-Histoquímica , Distribuição Aleatória , Reprodutibilidade dos Testes , Ratos Sprague-Dawley , Amarelo de Eosina-(YS) , Icterícia Obstrutiva/induzido quimicamente , Icterícia Obstrutiva/patologia , Fosfatase Alcalina/sangue , gama-Glutamiltransferase/sangue , Injeções , Cirrose Hepática/patologia , Verde de Metila
6.
Braz. arch. biol. technol ; 62: e19180338, 2019. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1011519

RESUMO

(1) Background: In this study, the effects of different pH values ​​(2.4, 3.2, 4.4 and 5.0), temperatures (30, 35, 40, 45 and 50°C) and agitation (100 rpm) on the enzymatic decolourisation of twenty-two dyes belonging to the chromophore groups anthraquinone, azo and triphenylmethane were assessed. (2) Methods: In all conditions, it was used a crude enzyme broth containing 30 U mL-1 laccases produced by Pleurotus sajor-caju PS-2001 in submerged process. (3) Results: Regarding the effects of pH values, the best results were obtained at pH 3.2 and 30°C, in which bleaching was observed for all dyes evaluated. In assays conducted at different temperatures, highest levels of decolourisation were observed at 35°C and pH 3.2 for nineteen of the dyes assessed. Thirteen dyes presented colour reduction exceeding 50% after the enzymatic treatment, including all acid and all disperse dyes evaluated. The reciprocal agitation of 100 rpm promoted negative effect on decolourisation. (4) Conclusion: From the results achieved, one can conclude that the laccase-containing preparation of P. sajor-caju PS-2001 has potential for the decolourisation of some dyes widely used in different industrial sectors, especially in the textile industry, and therefore could be used in future strategies for the biotreatment of coloured wastes.


Assuntos
Pleurotus/química , Lacase , Clareadores , Compostos Azo , Compostos de Tritil , Antraquinonas
7.
Braz. j. microbiol ; 49(2): 285-295, Apr.-June 2018. tab, graf
Artigo em Inglês | LILACS | ID: biblio-889238

RESUMO

Abstract Different technologies may be used for decolorization of wastewater containing dyes. Among them, biological processes are the most promising because they seem to be environmentally safe. The aim of this study was to determine the efficiency of decolorization of two dyes belonging to different classes (azo and triphenylmethane dyes) by immobilized biomass of strains of fungi (Pleurotus ostreatus - BWPH, Gleophyllum odoratum - DCa and Polyporus picipes - RWP17). Different solid supports were tested for biomass immobilization. The best growth of fungal strains was observed on the washer, brush, grid and sawdust supports. Based on the results of dye adsorption, the brush and the washer were selected for further study. These solid supports adsorbed dyes at a negligible level, while the sawdust adsorbed 82.5% of brilliant green and 19.1% of Evans blue. Immobilization of biomass improved dye removal. Almost complete decolorization of diazo dye Evans blue was reached after 24 h in samples of all strains immobilized on the washer. The process was slower when the brush was used for biomass immobilization. Comparable results were reached for brilliant green in samples with biomass of strains BWPH and RWP17. High decolorization effectiveness was reached in samples with dead fungal biomass. Intensive removal of the dyes by biomass immobilized on the washer corresponded to a significant decrease in phytotoxicity and a slight decrease in zootoxicity of the dye solutions. The best decolorization results as well as reduction in toxicity were observed for the strain P. picipes (RWP17).


Assuntos
Basidiomycota/metabolismo , Poluentes Químicos da Água/metabolismo , Corantes/metabolismo , Compostos Azo/metabolismo , Compostos de Tritil/metabolismo , Biotransformação , Células Imobilizadas/metabolismo , Adsorção , Águas Residuárias
8.
An. bras. dermatol ; 93(3): 415-418, May-June 2018. graf
Artigo em Inglês | LILACS | ID: biblio-949896

RESUMO

Abstract: The special picrosirius red staining highlights the natural birefringence of collagen fibers when exposed to polarized light. The results from birefringence allow to evaluate the organization of the collagen fibers in the tissues. The authors intend to elucidate all steps to obtain and capture images of histological sections stained with picrosirius red and evaluated under polarized light microscopy, as well as possible artefacts that may occur.


Assuntos
Animais , Cães , Pele/ultraestrutura , Coloração e Rotulagem/métodos , Compostos Azo/química , Colágeno/ultraestrutura , Microscopia de Polarização/métodos , Pele/citologia , Birrefringência , Administração Cutânea , Fotomicrografia , Colágeno/análise , Colágenos Fibrilares/ultraestrutura , Cavalos
9.
Braz. arch. biol. technol ; 61: e18160237, 2018. graf
Artigo em Inglês | LILACS | ID: biblio-974114

RESUMO

ABSTRACT Dye stuff released to the ecosystem from textile industries cause a serious contamination and become a major environmental problem over the last few decades. As biological decolorization of textile wastewater is an important issue, Fusarium . acuminatum was used to removal of a frequently used textile dye, methyl orange. Live pellet of Fusarium acuminatum was used and decolorization studies performed in various temperatures and pH conditions with different dye concentrations. The highest decolorization rate was observed at 35ᴼC. 60 mg/L was found as the optimum initial dye concentration. In the pH range of 3-4, decolorization rate was approximately 70%. It was seen that Fusarium acuminatum have the great ability of the methyl orange removal. To our knowledge, it took place for the first time in the literature.


Assuntos
Compostos Azo , Fusarium , Adsorção , Corantes
10.
Biosci. j. (Online) ; 33(5): 1340-1350, sept./oct. 2017. ilus, graf
Artigo em Inglês | LILACS | ID: biblio-966380

RESUMO

Biodecolorization of the azo dye Orange G was investigated using a new strain of Candida cylindracea SJL6, isolated from freshwater samples of the Subaé river in Bahia state, Brazil. Strain SJL6 was identified as C. cylindracea on the basis of 26S rDNA region. The various parameters of dye decolorization and cell growth were studied, including the Orange G dye concentration (100 to 500 ppm), temperature (20 to 40 °C), glucose concentration (0 to 5%), and initial pH (3 to 8). Biotoxicity tests were performed using shrimp (Artemia salina) to determine the lethal concentration (LC50) and onion bulbs (Allium cepa) to determine the cytotoxic and genotoxic effects of both Orange G dye and metabolites formed after decolorization. Up to 90% of decolorization of the Orange G dye at 500 ppm was achieved by C. cylindracea SJL6 at 30 °C, pH 3, and 1% glucose. However, the biotoxicity tests showed that there was increased toxicity after decolorization, suggesting partial Orange G dye degradation and production of toxic metabolites.


A biodescoloração do corante Alaranjado G foi investigada utilizando um novo isolado de Candida cylindracea SJL6, isolado de amostras de água do Rio Subaé, Bahia, Brasil. A linhagem SJL6 foi identificada como Candida cylindracea com base na região 26S do rDNA. Os parâmetros estudados na descoloração do corante e crescimento celular foram: concentração do Alaranjado G (100 a 500 ppm), temperatura (20 a 40 ºC), concentração de glicose (0 a 5%) e pH inicial (3 a 8). Os testes de biotoxicidade foram realizados utilizando o microcrustáceo Artemia salina para determinar a concentração letal (L50) e bulbos de cebola (Alium cepa) para determinar os efeitos citotóxicos e genotóxicos tanto do corante alaranjado G quanto dos metabólitos produzidos após a descoloração. Uma taxa de descoloração acima de 90% foi atingida a 500 ppm por C. cylindracea SJL6 a 30 ºC, pH 3 e 1% de glicose. Entretanto, os testes de biotoxicidade mostraram que ocorreu um aumento da toxicidade após a descoloração, o que sugere uma degradação parcial da molécula do corante Alaranjado G e produção de metabólitos tóxicos.


Assuntos
Compostos Azo , Biodegradação Ambiental , Candida , Fungos
11.
Electron. j. biotechnol ; 26: 7-11, Mar. 2017. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1009153

RESUMO

Background: Textile and dye industries pose a serious threat to the environment. Conventional methods used for dye treatment are generally not always effective and environmentally friendly. This drove attention of scores of researchers to investigate alternative methods for the biodegradation of dyes using fungal strains. In this work, white-rot fungus (Panus tigrinus) was used as a biosorbent for the decolorization of Reactive Blue 19. The process parameters that were varied were initial concentration (50­150 mg/L), contact time (30­90 min), and pH (2­6). In addition, to gain important data for the evaluation of a sorption process, the equilibrium and kinetics of the process were determined. Results: White-rot fungus showed great potential in decolorizing Azo dyes. The strain showed the maximum decolorization of 83.18% at pH 2, a contact time of 90 min, and an initial concentration of 50 mg/L. The Langmuir isotherm described the uptake of the Reactive Blue 19 dye better than the Freundlich isotherm. Analysis of the kinetic data showed that the dye uptake process followed the pseudo second-order rate expression. Conclusion: The biosorption process provided vital information on the process parameters required to obtain the optimum level of dye removal. The isotherm study indicated the homogeneous distribution of active sites on the biomass surface, and the kinetic study suggested that chemisorption is the rate-limiting step that controlled the biosorption process. According to the obtained results, P. tigrinus biomass can be used effectively to decolorize textile dyes and tackle the pollution problems in the environment.


Assuntos
Basidiomycota/química , Antraquinonas/química , Corantes/química , Temperatura , Compostos Azo/química , Indústria Têxtil , Fatores de Tempo , Basidiomycota/metabolismo , Biodegradação Ambiental , Cinética , Adsorção , Isoterma , Concentração de Íons de Hidrogênio
12.
Braz. j. microbiol ; 47(1): 39-46, Jan.-Mar. 2016. graf
Artigo em Inglês | LILACS | ID: lil-775119

RESUMO

Abstract Removal of synthetic dyes is one of the main challenges before releasing the wastes discharged by textile industries. Biodegradation of azo dyes by alkaliphilic bacterial consortium is one of the environmental-friendly methods used for the removal of dyes from textile effluents. Hence, this study presents isolation of a bacterial consortium from soil samples of saline environment and its use for the decolorization of azo dyes, Direct Blue 151 (DB 151) and Direct Red 31 (DR 31). The decolorization of azo dyes was studied at various concentrations (100–300 mg/L). The bacterial consortium, when subjected to an application of 200 mg/L of the dyes, decolorized DB 151 and DR 31 by 97.57% and 95.25% respectively, within 5 days. The growth of the bacterial consortium was optimized with pH, temperature, and carbon and nitrogen sources; and decolorization of azo dyes was analyzed. In this study, the decolorization efficiency of mixed dyes was improved with yeast extract and sucrose, which were used as nitrogen and carbon sources, respectively. Such an alkaliphilic bacterial consortium can be used in the removal of azo dyes from contaminated saline environment.


Assuntos
Compostos Azo/metabolismo , Bactérias/metabolismo , Cor , Resíduos Industriais , Consórcios Microbianos , Biotransformação , Bactérias/crescimento & desenvolvimento , Bactérias/isolamento & purificação , Carbono/metabolismo , Concentração de Íons de Hidrogênio , Nitrogênio/metabolismo , Microbiologia do Solo , Temperatura
13.
Braz. j. med. biol. res ; 48(11): 1055-1062, Nov. 2015. tab, graf
Artigo em Inglês | LILACS | ID: lil-762909

RESUMO

Heterotopic ossification (HO) is a metaplastic biological process in which there is newly formed bone in soft tissues, resulting in joint mobility deficit and pain. Different treatment modalities have been tried to prevent HO development, but there is no consensus on a therapeutic approach. Since electrical stimulation is a widely used resource in physiotherapy practice to stimulate joint mobility, with analgesic and anti-inflammatory effects, its usefulness for HO treatment was investigated. We aimed to identify the influence of electrical stimulation on induced HO in Wistar rats. Thirty-six male rats (350-390 g) were used, and all animals were anesthetized for blood sampling before HO induction, to quantify the serum alkaline phosphatase. HO induction was performed by bone marrow implantation in both quadriceps of the animals, which were then divided into 3 groups: control (CG), transcutaneous electrical nerve stimulation (TENS) group (TG), and functional electrical stimulation (FES) group (FG) with 12 rats each. All animals were anesthetized and electrically stimulated twice per week, for 35 days from induction day. After this period, another blood sample was collected and quadriceps muscles were bilaterally removed for histological and calcium analysis and the rats were killed. Calcium levels in muscles showed significantly lower results when comparing TG and FG (P<0.001) and between TG and CG (P<0.001). Qualitative histological analyses confirmed 100% HO in FG and CG, while in TG the HO was detected in 54.5% of the animals. The effects of the muscle contractions caused by FES increased HO, while anti-inflammatory effects of TENS reduced HO.


Assuntos
Animais , Masculino , Ossificação Heterotópica/terapia , Músculo Quadríceps , Estimulação Elétrica Nervosa Transcutânea , Anti-Inflamatórios , Compostos Azo , Fosfatase Alcalina/sangue , Transplante de Medula Óssea , Estudos Transversais , Cálcio/análise , Modelos Animais de Doenças , Terapia por Estimulação Elétrica , Amarelo de Eosina-(YS) , Verde de Metila , Ossificação Heterotópica/etiologia , Ossificação Heterotópica/patologia , Músculo Quadríceps/química , Músculo Quadríceps/patologia , Distribuição Aleatória , Ratos Wistar , Transplante Autólogo
14.
Ciênc. Saúde Colet. (Impr.) ; 20(1): 145-153, jan. 2015.
Artigo em Inglês, Português | BDS, LILACS | ID: lil-733130

RESUMO

In this paper, the question of Brazil's insertion today as a country with the characteristics of modern consumer societies is discussed, focusing on the commercialization of the health sector, the segmentation of the health system and the contradictions of the rights to health care in the social context in question. Some research data on these issues broadcast in the National News Bulletins of Globo TV during the year of 2012 are presented, in which the high technology private hospital as a consumer icon, the underfunding of the public health system and the rejection of a poor and deprived Unified Health System are analyzed.


Discute-se aqui a nossa inserção como país, hoje, nas sociedades de consumo características da modernidade, enfocando a mercantilização na área da saúde, a segmentação do sistema de saúde e as contradições do direito à saúde no contexto social em questão. São apresentados dados de pesquisa sobre o tema no Jornal Nacional da Rede Globo de Televisão, durante o ano de 2012, na qual se analisa o hospital privado de alto padrão tecnológico como ícone de consumo, o subfinanciamento do sistema público de saúde e a rejeição de um Sistema Único de Saúde pobre e carente.


Assuntos
Compostos Azo/análise , Cromatografia em Gel/métodos , Cromatografia Líquida de Alta Pressão/métodos , Espectrometria de Massas por Ionização por Electrospray/métodos , Especiarias/análise , Espectrometria de Massas em Tandem/métodos , Compostos Azo/química , Capsicum/química , Análise de Alimentos/métodos , Corantes de Alimentos/análise , Corantes de Alimentos/química , Estrutura Molecular , Naftóis/análise , Naftóis/química , Reprodutibilidade dos Testes
15.
Int. j. morphol ; 32(4): 1266-1270, Dec. 2014. ilus
Artigo em Espanhol | LILACS | ID: lil-734669

RESUMO

La significancia funcional de cualquier relación que exista entre la orientación de las fibras de colágeno y la tensión ejercida sobre una estructura ósea dependerá de la influencia de estos parámetros microestructurales sobre las propiedades biomecánicas del hueso y su capacidad de adaptarse. Se estudió la localización del colágeno en el hueso sesamoídeo distal (HSD) de la mano en equinos con Síndrome Navicular para observar cómo este refleja las demandas biomecánicas ejercidas por la tensión que ejerce el tendón del músculo flexor digital profundo sobre la articulación interfalángica distal. Se utilizaron las tinciones hematoxilina-eosina-azul alcián, y Rojo Picrosirius de Junqueira. La birrefringencia de colágeno óseo fue determinada utilizando microscopía de luz polarizada. La remodelación del HSD resultó en la formación de osteonas secundarias transversales orientados en una dirección lateral a medial y el colágeno óseo se orientó de manera similar. Estos resultados proporcionan evidencia de la existencia de una relación entre la función mecánica de un hueso con su arquitectura, incluso demuestra que esta se extiende hasta el nivel molecular.


The functional significance of any relationship exists between the orientation of the collagen fibers and the strain on a bone structure depend on the influence of these microstructural parameters on the biomechanical properties of bone and its ability to adapt. Localization of collagen was studied in the distal sesamoid bone (DSB) in in equine foot with Navicular Syndrome to see how this reflects the biomechanical demands by the tension exerted by the tendon of the deep digital flexor muscle on the joint distal interphalangeal. Hematoxylin-eosin-alcian blue staining, and Red Picrosirius of Junqueira were used. The birefringence of bone collagen was determined using polarized light microscopy. The remodeling of DSB resulted in the formation of transverse secondary osteons oriented lateral to medial and bone collagen was oriented in similar direction. These results provide evidence for the existence of a relationship between the mechanical function of a bone with the architecture, and shows further that this extends up to the molecular level.


Assuntos
Animais , Ossos Sesamoides/patologia , Colágeno/metabolismo , Doenças do Pé/veterinária , Doenças dos Cavalos , Compostos Azo , Imuno-Histoquímica , Colágeno/ultraestrutura
16.
Braz. j. microbiol ; 45(4): 1153-1160, Oct.-Dec. 2014. ilus, tab
Artigo em Inglês | LILACS | ID: lil-741264

RESUMO

The present work aimed to investigate the microbial dynamics during the anaerobic treatment of the azo dye blue HRFL in bench scale upflow anaerobic sludge bed (UASB) reactor operated at ambient temperature. Sludge samples were collected under distinct operational phases, when the reactor were stable (low variation of color removal), to assess the effect of glucose and yeast extract as source of carbon and redox mediators, respectively. Reactors performance was evaluated based on COD (chemical oxygen demand) and color removal. The microbial dynamics were investigated by PCR-DGGE (Polimerase Chain Reaction - Denaturing Gradient of Gel Electrophoresis) technique by comparing the 16S rDNA profiles among samples. The results suggest that the composition of microorganisms changed from the beginning to the end of the reactor operation, probably in response to the presence of azo dye and/or its degradation byproducts. Despite the highest efficiency of color removal was observed in the presence of 500 mg/L of yeast extract (up to 93%), there were no differences regarding the microbial profiles that could indicate a microbial selection by the yeast extract addition. On the other hand Methosarcina barkeri was detected only in the end of operation when the best efficiencies on color removal occurred. Nevertheless the biomass selection observed in the last stages of UASB operation is probably a result of the washout of the sludge in response of accumulation of aromatic amines which led to tolerant and very active biomass that contributed to high efficiencies on color removal.


Assuntos
Compostos Azo/metabolismo , Biota , Análise da Demanda Biológica de Oxigênio , Biotransformação , Reatores Biológicos/microbiologia , Análise por Conglomerados , Cor , Eletroforese em Gel de Gradiente Desnaturante , DNA Ribossômico/química , DNA Ribossômico/genética , Dados de Sequência Molecular , Filogenia , Reação em Cadeia da Polimerase , /genética , Análise de Sequência de DNA , Esgotos/microbiologia
17.
Braz. dent. j ; 25(6): 508-518, Nov-Dec/2014. tab, graf
Artigo em Inglês | LILACS | ID: lil-732262

RESUMO

The postural risk factors for dentists include the ease of vision in the workplace, cold, vibration and mechanical pressure in tissues, incorrect posture, functional fixity, cognitive requirements and work-related organizational and psychosocial factors. The objective was to analyze the posture of endodontists at the workplace. Eighteen right-handed endodontists aged 25 to 60 years (34±3) participated in the study. Electromyography, kinemetry, ergonomic scales (RULA and Couto's checklist) and biophotogrammetry were used to analyze the posture of endodontists during root canal treatment of the maxillary right first and second molars using rotary and manual instrumentation. The variations observed in the electromyographic activities during the performance of rotary and manual techniques suggest that the fibers of the longissimus region, anterior and medium deltoid, medium trapezium, biceps, triceps brachii, brachioradialis and short thumb abductor muscles underwent adaptations to provide more accurate functional movements. Computerized kinemetry and biophotogrammetry showed that, as far as posture is concerned, rotary technique was more demanding than the manual technique. In conclusion, the group of endodontists evaluated in this study exhibited posture disorders regardless of whether the rotary or manual technique was used.


Os fatores de risco posturais para cirurgiões dentistas incluem o acesso a visão no local de trabalho, frio, vibração, pressão mecânica nos tecidos, postura incorreta, alterações funcionais, requisitos cognitivos e fatores organizacionais e psicossociais relacionados com o trabalho. O objetivo é analisar a postura dos endodontistas no local de trabalho. Participaram dezoito endodontistas destros com idades entre as idades de 25 e 60 anos (34±3). Nesta pesquisa foi utilizado a eletromiografia, cinemetria, escalas de ergonomia (do RULA e Couto checklist) e biofotogrametria para analisar a postura dos endodontistas durante o preparo químico-mecânico do sistema de canais radiculares para primeiros e segundos molares superiores direitos, utilizando a instrumentação rotatória e manual. As variações observadas nas atividades eletromiográficas durante a execução das técnicas rotatórias e manuais sugerem que as fibras da região dos músculos longuíssimo, deltóide anterior e médio, trapézio médio, bíceps, tríceps braquial, braquiorradial e músculos abdutores curtos do polegar passaram por adaptações para promover movimentos funcionais mais precisos. A cinemetria e biofotogrametria computadorizada mostraram que a técnica rotatória foi mais exigente da postura corporal do que a técnica manual. Em conclusão, os endodontistas estudados apresentaram distúrbios de postura, independentemente da técnica utilizada, rotatória ou manual.


Assuntos
Compostos Azo/análise , Corantes/análise , Naftóis/análise , Poluentes Químicos da Água/análise , Poluentes da Água/análise , p-Dimetilaminoazobenzeno/análise , Cromatografia Líquida de Alta Pressão , Espectrofotometria Ultravioleta
18.
Braz. j. phys. ther. (Impr.) ; 18(6): 502-512, 09/01/2015. tab, graf
Artigo em Inglês | LILACS | ID: lil-732355

RESUMO

OBJECTIVE: To systematically review the available evidence on the efficacy of walking training associated with virtual reality-based training in patients with stroke. The specific questions were: Is walking training associated with virtual reality-based training effective in increasing walking speed after stroke? Is this type of intervention more effective in increasing walking speed, than non-virtual reality-based walking interventions? METHOD: A systematic review with meta-analysis of randomized clinical trials was conducted. Participants were adults with chronic stroke and the experimental intervention was walking training associated with virtual reality-based training to increase walking speed. The outcome data regarding walking speed were extracted from the eligible trials and were combined using a meta-analysis approach. RESULTS: Seven trials representing eight comparisons were included in this systematic review. Overall, the virtual reality-based training increased walking speed by 0.17 m/s (IC 95% 0.08 to 0.26), compared with placebo/nothing or non-walking interventions. In addition, the virtual reality-based training increased walking speed by 0.15 m/s (IC 95% 0.05 to 0.24), compared with non-virtual reality walking interventions. CONCLUSIONS: This review provided evidence that walking training associated with virtual reality-based training was effective in increasing walking speed after stroke, and resulted in better results than non-virtual reality interventions. .


OBJETIVO: Revisar estudos sobre a eficácia do treino direcionado à marcha associado à realidade virtual em pacientes pós-acidente vascular encefálico (AVE). As perguntas clínicas foram: o treino direcionado à marcha associado à realidade virtual é eficaz para promover aumento em velocidade de marcha de indivíduos com hemiparesia? Essa modalidade de intervenção promove maior aumento em velocidade de marcha comparada a outras intervenções sem uso de realidade virtual? MÉTODO: Foi realizada uma revisão sistemática com metanálise de ensaios clínicos aleatorizados. Os participantes eram adultos pós-AVE, e a intervenção experimental considerada foi o treino direcionado à marcha associado ao uso de realidade virtual com o objetivo de melhorar a velocidade de marcha. Os dados referentes à velocidade de marcha foram extraídos para combinação por metanálise. RESULTADOS: Sete estudos representando oito comparações foram incluídos nesta revisão sistemática. O treino de marcha associado à realidade virtual aumentou a velocidade de marcha dos participantes, em média, 0,17 m/s (IC 95% 0,08 a 0,26) comparado à intervenção placebo, não intervenção ou intervenção não específica para os membros inferiores. Adicionalmente, o treino associado à realidade virtual aumentou a velocidade de marcha dos participantes, em média, 0,15 m/s (IC 95% 0,05 a 0,24) comparado a diferentes intervenções destinadas aos membros inferiores sem uso de realidade virtual associada. CONCLUSÕES: Esta revisão sistemática apresentou evidência clínica de que a adição da realidade virtual ao treino de marcha demonstrou ser eficaz para aumentar a velocidade de marcha de indivíduos com hemiparesia ...


Assuntos
Compostos Azo/análise , Naftóis/análise , Cromatografia Gasosa-Espectrometria de Massas , Espectrometria de Massas , Solventes
19.
Dental press j. orthod. (Impr.) ; 19(6): 93-98, Nov-Dec/2014. tab, graf
Artigo em Inglês | LILACS | ID: lil-732433

RESUMO

OBJECTIVE: This study aimed to assess tissue changes during orthodontic movement after binge-pattern ethanol 20% exposure. METHODS: Male Wistar rats (n = 54) were divided into two groups. The control group (CG) received 0.9% saline solution, while the experimental group (EG) received 20% ethanol in 0.9% saline solution (3 g/kg/day). On the 30th day, a force of 25 cN was applied with a nickel-titanium closed coil spring to move the maxillary right first molar mesially. The groups were further divided into three subgroups (2, 14 and 28 days). Tartrate-resistant acid phosphatase and picrosirius were used to assess bone resorption and neoformation, respectively. Data were compared by two-way ANOVA, Tukey's HSD, Games-Howell and chi-square test. Significance level was set at 5%. RESULTS: There was a decrease in the number of osteoclasts in EG at day 28. The percentage of collagen showed no interaction between group and time. CONCLUSION: Binge-pattern 20% ethanol promoted less bone resorption at the end of tooth movement, thereby suggesting delay in tooth movement. .


OBJETIVO: objetivou-se avaliar as alterações teciduais decorrentes da administração de etanol a 20% no padrão binge, durante o movimento ortodôntico. MÉTODOS: foram utilizados ratos Wistar machos (n = 54), divididos em dois grupos, sendo Grupo Controle (GC), com administração de soro fisiológico a 0,9%; e Grupo e Experimental (GE), com administração de etanol a 20% em soro fisiológico a 0,9%, no volume de 3g/kg/dia. Após o 30º dia de administração, foi aplicada força de 25cN com mola fechada de níquel-titânio para mover o primeiro molar superior direito para mesial. Os grupos foram subdivididos nos subgrupos 2, 14 e 28 dias, correspondendo ao número de dias de movimentação dentária. Utilizou-se as colorações de fosfatase ácida-tartarato resistente e picrosírius para avaliar reabsorção óssea e neoformação óssea, respectivamente. Os dados foram comparados por ANOVA a dois critérios, Tukey HSD e Games-Howell, ao nível de significância de 5%. RESULTADOS: verificou-se diminuição no número de osteoclastos no GE II no 28º dia. A percentagem de colágeno não demonstrou alteração na interação grupo x tempo. CONCLUSÕES: o etanol no padrão binge a 20% promoveu menor reabsorção óssea no final da movimentação dentária, sugerindo atraso na movimentação dentária. .


Assuntos
Animais , Masculino , Ratos , Consumo Excessivo de Bebidas Alcoólicas/complicações , Técnicas de Movimentação Dentária/métodos , Compostos Azo , Fosfatase Ácida/análise , Processo Alveolar/patologia , Reabsorção Óssea/patologia , Reabsorção Óssea/fisiopatologia , Contagem de Células , Corantes , Colágeno Tipo I/análise , Ligas Dentárias/química , Isoenzimas/análise , Dente Molar/patologia , Níquel/química , Fios Ortodônticos , Osteoclastos/patologia , Osteogênese/fisiologia , Ligamento Periodontal/patologia , Distribuição Aleatória , Ratos Wistar , Fatores de Tempo , Titânio/química , Técnicas de Movimentação Dentária/instrumentação
20.
Electron. j. biotechnol ; 15(6): 8-8, Nov. 2012. ilus, tab
Artigo em Inglês | LILACS | ID: lil-662206

RESUMO

Six strains of white-rot fungi isolated from southern Chile were evaluated for their ergosterol/biomass correlation and ligninolytic potential in solid medium to formulate pellets for Reactive Orange 165 (RO165) decolourization. The fungus Anthracophyllum discolor was selected to formulate complex pellets (fungal mycelium, sawdust, and activated carbon), coated pellets (complex pellet + alginate) and simple pellets (fungal mycelium). The activity of ligninolytic enzymes (laccase, manganese peroxidase, manganese-independent peroxidase, and lignin peroxidase) was evaluated in both the complex and coated pellets in modified Kirk medium, and the morphology of the pellets was studied using scanning electron microscopy (SEM). Complex pellets of A. discolor showed a higher enzymatic production mainly MnP (38 U L-1 at day 15) compared to coated and simple pellets. Examinations using SEM showed that both pellets produced a black core that was entrapped by a layer of fungal mycelium. Decolourization of RO165 was demonstrated with all the pellets formulated. However, the highest and fastest decolourization was obtained with complex pellets (100 percent at day 8). Therefore, complex pellets of A. discolor can be used for the biological treatment of wastewater contaminated with RO165.


Assuntos
Compostos Azo , Agaricales/enzimologia , Biodegradação Ambiental , Corantes , Lignina , Remoção de Contaminantes/métodos
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