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1.
Chem Biodivers ; 20(2): e202200888, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36703594

RESUMO

Aiming of self-sustainable production, the search for biodegradable and biocompatible materials has brought with it the need to know the physicochemical and dielectric characteristics of polysaccharide-based composite structures, which can be used as important and promising raw materials for biotechnology and electronic industries. Galactomannans are polysaccharides, extracted from seeds and microbiological sources, consisting of mannose and galactose. In this context, this work aimed to extract, purify and characterize by XRD, FTIR and impedance spectroscopy galactomannan obtained from seeds of Adenanthera pavonina L. The purification process was made with ethyl alcohol at concentrations of 70, 80 and 90 %. Polymeric films were prepared by solvent slow evaporation at low temperatures. XRD measurements revealed that Galactomannan from Adenanthera pavonina L., after purification, has a semi-crystalline structure due to the identification of two peaks the first between 5.849° and 6.118° and the second between 20.011° and 20.247°. FTIR spectra showed the functional groups associated with monosaccharides of the galactomannan from Adenanthera pavonina L. seeds, as well as the typical polysaccharide bands and peaks, confirmed by literature data. The impedance results give an increment on the state-of-the-art of this biomaterial by showing the existence of dielectric relaxations, independent of the degree of purification, using the dielectric modulus formalism. The permittivity analysis reveals the presence of water in the structure of the film, whose dipoles contribute to the relatively high value of the dielectric constant. From the results obtained, it can be concluded that purified galactomannan has the potential for possible applications in the electronics industry as a green and eco-friendly dielectric material.


Assuntos
Fabaceae , Mananas , Mananas/análise , Mananas/química , Fabaceae/química , Polissacarídeos/química , Galactose , Sementes/química , Materiais Biocompatíveis
2.
Arq. bras. med. vet. zootec. (Online) ; 70(6): 1798-1806, nov.-dez. 2018. mapas, tab
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-970480

RESUMO

The objective of this study was to conduct an investigation of Mycoplasma bovigenitalium and Ureaplasma diversum infections in cattle in the microregion of the Ipanema Valley, state of Pernambuco, Brazil. Vaginal swabs were collected from 355 breeding cows in reproductive age and were analyzed by multiplex PCR (mPCR) and culture. An epidemiological investigation of risk factors was performed for Mollicutes. mPCR analysis showed that, 9.29% (33/355) of the cows were positive for M. bovigenitalium and 21.69% (77/355) for U. diversum; coinfection was observed in 2.81% (10/355) of the cows. The microbiological isolation showed, 81.81% (27/33) of Mycoplasma spp. and 24.67% (19/77) of Ureaplasma spp.. The risk factors related to Mollicutes infection identified were semi-intensive breeding system (OR= 4.6), pasture rent (OR= 3.6), non-isolation of animals with reproductive disorders (OR= 3.2), and natural mounting and artificial insemination (OR= 3.5). There was a significant association between Mollicutes infection and abortions in the first gestational third (P= 0.001). This is the first record of M. bovigenitalium and U. diversum infection in cows in the semiarid region of the state of Pernambuco, Brazil. Preventive measures directed to the identified risk factors can decrease the occurrence of Mollicutes in these herds.(AU)


O objetivo deste estudo foi realizar uma investigação de Mycoplasma bovigenitalium e Ureaplasma diversum em bovinos leiteiros da microrregião do Vale do Ipanema, estado de Pernambuco, Brasil. Foram coletados suabes vaginais de 355 vacas em idade reprodutiva. As amostras foram analisadas por multiplex PCR (mPCR) e cultura. Foi realizada uma investigação dos fatores de risco para Mollicutes. Na mPCR, 9,29% (33/355) das vacas foram positivas para M. bovigenitalium e 21,69% (77/355) para U. diversum; coinfecção foi observada em 2,81% (10/355) das vacas. O isolamento microbiológico mostrou crescimento de Mycoplasma spp. em 81,81% (27/33) das amostras e em 24,67% (19/77) para Ureaplasma spp. Os fatores de risco relacionados à infecção por Mollicutes identificados foram sistema de produção semi-intensivo (OR= 4,6), aluguel de pastagem (OR= 3,6), não isolamento de animais com desordens reprodutivas (OR= 3,2) e monta natural e inseminação artificial (OR= 3,5). Houve uma associação significativa entre a infecção por Mollicutes e abortos no primeiro terço gestacional (P=0,001). Este é o primeiro relato da infecção por M. bovigenitalium e U. diversum em vacas na região semiárida do estado de Pernambuco, Brasil. As medidas preventivas direcionadas aos fatores de risco identificados podem diminuir a ocorrência de Mollicutes nesses rebanhos.(AU)


Assuntos
Animais , Feminino , Bovinos , Bovinos/microbiologia , Infecções por Ureaplasma/veterinária , Mycoplasma bovigenitalium/patogenicidade , Reação em Cadeia da Polimerase Multiplex/estatística & dados numéricos
3.
Acta Biomater ; 3(5): 773-8, 2007 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-17468060

RESUMO

The present study focuses on apatite coating on collagen films, with various different densities of carboxyl groups, using an alternate soaking process. Anionic collagen (AC), which has different densities of carboxylic groups compared to native collagen (NC), was obtained by hydrolysis of carboxyamides of asparagine and glutamine residues. From X-ray diffraction analysis, apatite was found to be coated on AC and NC films. Peaks ascribed to apatite were observed at 26 degrees and 32 degrees in the diffraction patterns of hydroxyapatite crystals. The amount of apatite coated on both AC and NC collagen films continued to increase up to 100 reaction cycles. However, there is a significant difference in apatite coating between the two films. The amount of apatite formed on the surface of AC film increased 1.24 times faster than on NC film. The scanning electron photomicrograph images of the mineralized NC and the AC film coatings formed after 100cycles show that regular porous apatite coating had formed within the collagen fibrils. These results suggest that the higher content of carboxyl groups in AC plays an effective role in the heterogeneous nucleation of apatite in the body environment.


Assuntos
Apatitas/química , Materiais Revestidos Biocompatíveis/química , Colágeno/química , Membranas Artificiais , Ânions , Teste de Materiais , Soluções , Propriedades de Superfície
4.
Biophys Chem ; 120(2): 154-9, 2006 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-16337076

RESUMO

In this paper, impedance measurements in the frequency range from 10(-2) to 10(6) Hz are presented for collagen and algal sulfated polysaccharide crosslinked films. We are considering the development of new biomaterials which have potential applications in coating of cardiovascular prostheses, support for cellular growth and in systems for controlled drug delivery. The effect of crosslink sulfated polysaccharide on the physical chemical properties of collagen was studied using FT-infrared spectroscopy, differential scanning calorimetry (DSC), dielectric spectroscopy. The resulting films crosslinked with glutaraldehyde (GA) in concentrations of 0.001% and 0.05% when analysed by DSC, showed that the GA treatment not only left the thermal stability of the collagen unaffected, but it also decreased the thermal transition energy. Dielectric spectroscopy shows that the effect of the crosslink on the blend film was associated to the decrease and stabilization of the dielectric permittivity at low frequencies and decreased its conductivity.


Assuntos
Colágeno/química , Reagentes de Ligações Cruzadas/farmacologia , Eucariotos/química , Glutaral/farmacologia , Polissacarídeos/química , Sulfatos/química , Materiais Biocompatíveis , Varredura Diferencial de Calorimetria , Eletroquímica , Espectroscopia de Infravermelho com Transformada de Fourier
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