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1.
Photodiagnosis Photodyn Ther ; 18: 193-197, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28238893

RESUMO

Photodynamic therapy (PDT) is a modality of therapy that involves the activation of photosensitive substances and the generation of cytotoxic oxygen species and free radicals to promote the selective destruction of target tissues. This study analyzed the application of PDT to Tritrichomonas foetus, a scourged and etiological agent of bovine trichomoniasis, a sexually transmitted infectious disease. As it is an amitochondrial and aerotolerant protozoan, it produces energy under low O2 tension via hydrogenosome. T. foetus from an axenic culture was incubated with photosensitizer tetrasulfonated aluminium phthalocyanine and then irradiated with a laser source (InGaAIP) at a density of 4.5Jcm-2. The DNA integrity of the control and treated group parasites was analyzed by conventional gel electrophoresis and comet assay techniques. In previous results, morphological changes characterized by apoptotic cell death were observed after T. foetus was submitted to PDT treatment. In the treated groups, T. foetus DNA showed a higher concentration of small fragments, about 200pb, in gel electrophoresis after PDT. In the comet assay, the DNA tail percentage was significantly higher in the treated groups. These results demonstrate that PDT leads to DNA fragmentation with changes in nuclear morphology and apoptotic features.


Assuntos
Bovinos/parasitologia , Dano ao DNA/genética , DNA de Protozoário/genética , DNA de Protozoário/efeitos da radiação , Fotoquimioterapia/métodos , Tritrichomonas foetus/efeitos dos fármacos , Tritrichomonas foetus/genética , Animais , DNA de Protozoário/efeitos dos fármacos , Relação Dose-Resposta a Droga , Relação Dose-Resposta à Radiação , Doses de Radiação , Tritrichomonas foetus/efeitos da radiação
2.
Rev. bras. plantas med ; 16(4): 804-811, oct.-dic. 2014. graf, tab
Artigo em Inglês | LILACS | ID: lil-729887

RESUMO

This study sought to evaluate the chemical composition of the Allium sativum and Origanum vulgare essential oils and their effect on the growth inhibition of microorganisms, such as P. aeruginosa, S. Choleraesuis, A. flavus, A. niger and P. simplicissimum, important food contaminants. The main constituents of the oregano essential oil were 4-terpineol (27.03%), γ-terpinene (20.04%), and β-cymene (6.34%), and the main constituents of the garlic essential oil were diallyl trisulfide (38, 81%), diallyl disulfide (25.23%), and methyl allyl trisulfide (12.52%). Inhibition zones were formed in in vitro tests on the bacteria S. Choleraesuis and P. aeruginosa, except for A. sativum against P. aeruginosa. The inhibition of mycelial growth caused by the oregano essential oil occurred with the concentrations of 0.10, 0.03 and 0.05 mg mL-1 for the A. flavus, A. niger and P. simplicissimum fungi, respectively. The CMI for the garlic oil began at the 0.03 mg mL-1 concentration for all species of fungi. The oils presented an inhibitory effect against the microorganisms studied and constitute an alternative for microbiological control in food.


Objetivou-se avaliar a composição química e o efeito inibitório dos óleos essenciais de Allium sativum e Origanum vulgare frente ao crescimento dos micro-organismos Pseudomonas aeruginosa, Salmonella Choleraesuis, Aspergillus flavus, Aspergillus niger e Penicillium simplicissimum, importantes patógenos causadores de contaminações em alimentos. Para quantificação e identificação dos constituintes químicos dos óleos, utilizou-se cromatógrafo gasoso acoplado a espectrômetro de massas. Os principais constituintes do óleo essencial de orégano foram o 4-terpineol (27,03%), γ-terpineno (20,04%), β-cimeno (6,34%), e do alho, o dialil trissulfeto (38,81%), dialil dissulfeto (25,23%), metil alil trissulfeto (12,52%). Os resultados dos testes in vitro sobre as bactérias S. Choleraesuis e P. aeruginosa indicaram a formação de halo de inibição e revelaram o efeito inibitório para os referidos óleos, exceto para o óleo de A. sativum frente a P. aeruginosa. Para os fungos A. flavus, A. niger e P. simplicissimum a inibição do crescimento micelial provocada pelo óleo essencial de orégano ocorreu a partir das concentrações de 0,10, 0,03 e 0,05 µg mL-1, respectivamente, sendo que a CMI para o óleo de alho iniciou-se a partir da concentração 0,03 µg mL-1 para todas as espécies de fungos. Foi possível verificar que os óleos possuem efeito inibitório sobre os microrganismos estudados, sendo, portanto, uma alternativa no controle microbiológico de alimentos.


Assuntos
Óleos Voláteis/química , /farmacologia , Química , Alho/metabolismo , Noxas/efeitos adversos , Contaminantes Químicos em Alimentos
3.
Med Biol Eng Comput ; 48(6): 573-7, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20390460

RESUMO

This study analyzes the performance of knee extension and flexion of Taekwondo and Kickboxing athletes. The power values were extracted through electromyography obtained by an isokinetic dynamometer at 60 degrees per second. These values are resulted from the square of the electromyography signal. The analysis of kick power was made using a modified wavelet algorithm considering values with 95% significance. Both groups presented equivalent power and torque capacity with different training times and experience, on the other hand, the wavelet analysis showed better results in muscular recruitment performance in athletes with more experience, in other words, power is not only performance but also power plus recruitment produces better results. This study uniquely showed that muscular enhancement capacity is not only related to the power capacity of contraction but also to motor coordination.


Assuntos
Articulação do Joelho/fisiologia , Artes Marciais/fisiologia , Músculo Esquelético/fisiologia , Adolescente , Fenômenos Biomecânicos , Eletromiografia/métodos , Humanos , Masculino , Processamento de Sinais Assistido por Computador , Adulto Jovem
4.
Braz. j. med. biol. res ; 42(5): 433-437, May 2009. ilus, tab
Artigo em Inglês | LILACS | ID: lil-511340

RESUMO

Assuming that the IS6110-restriction fragment length polymorphism (RFLP) changes at a constant rate of 3.2 years, this methodology was applied to demonstrate, for the first time, variant patterns of Mycobacterium tuberculosis (MTB) in multiple isolates obtained at short time intervals from sputum and blood of an HIV+ patient with multiple admissions to the Emergency Room and to the multidrug-resistant tuberculosis (MDR-TB) Reference Center of a secondary-care hospital in Rio de Janeiro, Brazil. In sputum, the IS6110-RFLP appeared in isolates with two variant patterns with 10 and 13 IS6110 copies. However, blood presented only the pattern corresponding to 10 copies, suggesting compartmentalization. With regard to the exact match of 10 of 13 bands, this may be a subpopulation with the same clonal origin and this may be related to the IS6110 transposition. A susceptibility test demonstrated an MDR profile (INH R, RIF R, SM R, and EMB R), with the sputum isolate also exhibiting EMB S (R = resistant; S = sensitive). A gene mutation confirmed resistance only to streptomycin. There was agreement between the results of the phenotypic test and the clinical response to MDR-TB treatment, suggesting serious implications with regard to treatment administration based exclusively on molecular methods, and calling attention to the fact that more effective control strategies against the emergence of MDR strains must be implemented by the TB control program to prevent transmission of MDR-MTB strains at health facilities in areas highly endemic for TB.


Assuntos
Humanos , Masculino , Pessoa de Meia-Idade , DNA Bacteriano/genética , Mutação/genética , Mycobacterium tuberculosis/genética , Tuberculose Resistente a Múltiplos Medicamentos/microbiologia , Infecções Oportunistas Relacionadas com a AIDS/microbiologia , Antituberculosos/farmacologia , Brasil , Impressões Digitais de DNA , Genótipo , Testes de Sensibilidade Microbiana , Mycobacterium tuberculosis/efeitos dos fármacos , Mycobacterium tuberculosis/isolamento & purificação , Fenótipo , Polimorfismo de Fragmento de Restrição
5.
Braz J Med Biol Res ; 42(5): 433-7, 2009 May.
Artigo em Inglês | MEDLINE | ID: mdl-19377792

RESUMO

Assuming that the IS6110-restriction fragment length polymorphism (RFLP) changes at a constant rate of 3.2 years, this methodology was applied to demonstrate, for the first time, variant patterns of Mycobacterium tuberculosis (MTB) in multiple isolates obtained at short time intervals from sputum and blood of an HIV+ patient with multiple admissions to the Emergency Room and to the multidrug-resistant tuberculosis (MDR-TB) Reference Center of a secondary-care hospital in Rio de Janeiro, Brazil. In sputum, the IS6110-RFLP appeared in isolates with two variant patterns with 10 and 13 IS6110 copies. However, blood presented only the pattern corresponding to 10 copies, suggesting compartmentalization. With regard to the exact match of 10 of 13 bands, this may be a subpopulation with the same clonal origin and this may be related to the IS6110 transposition. A susceptibility test demonstrated an MDR profile (INH(R), RIF(R), SM(R), and EMB(R), with the sputum isolate also exhibiting EMB(S) (R = resistant; S = sensitive). A gene mutation confirmed resistance only to streptomycin. There was agreement between the results of the phenotypic test and the clinical response to MDR-TB treatment, suggesting serious implications with regard to treatment administration based exclusively on molecular methods, and calling attention to the fact that more effective control strategies against the emergence of MDR strains must be implemented by the TB control program to prevent transmission of MDR-MTB strains at health facilities in areas highly endemic for TB.


Assuntos
DNA Bacteriano/genética , Mutação/genética , Mycobacterium tuberculosis/genética , Tuberculose Resistente a Múltiplos Medicamentos/microbiologia , Infecções Oportunistas Relacionadas com a AIDS/microbiologia , Antituberculosos/farmacologia , Brasil , Impressões Digitais de DNA , Genótipo , Humanos , Masculino , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Mycobacterium tuberculosis/efeitos dos fármacos , Mycobacterium tuberculosis/isolamento & purificação , Fenótipo , Polimorfismo de Fragmento de Restrição
6.
Proteins ; 58(2): 339-53, 2005 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-15562516

RESUMO

Using a data set of aligned protein domain superfamilies of known three-dimensional structure, we compared the location of interdomain interfaces on the tertiary folds between members of distantly related protein domain superfamilies. The data set analyzed is comprised of interdomain interfaces, with domains occurring within a polypeptide chain and those between two polypeptide chains. We observe that, in general, the interfaces between protein domains are formed entirely in different locations on the tertiary folds in such pairs. This variation in the location of interface happens in protein domains involved in a wide range of functions, such as enzymes, adapters, and domains that bind protein ligands, or cofactors. While basic biochemical functionality is preserved at the domain superfamily level, the effect of biochemical function on protein assemblies is different in these protein domains related by superfamily. The divergence between proteins, in most cases, is coupled with domain recruitment, with different modes of interaction with the recruited domain. This is in complete contrast to the observation that in closely related homologous protein domains, almost always the interaction interfaces are topologically equivalent. In a small subset of interacting domains within proteins related by remote homology, we observe that the relative positioning of domains with respect to one another is preserved. Based on the analysis of multidomain proteins of known or unknown structure, we suggest that variation in protein-protein interactions in members within a superfamily could serve as diverging points in otherwise parallel metabolic or signaling pathways. We discuss a few representative cases of diverging pathways involving domains in a superfamily.


Assuntos
Biologia Computacional/métodos , Proteínas/química , Proteômica/métodos , Animais , Proteínas Arqueais/química , Proteínas de Bactérias/química , Sítios de Ligação , Sequência Conservada , Bases de Dados de Proteínas , Dimerização , Evolução Molecular , Humanos , Modelos Moleculares , Dados de Sequência Molecular , Família Multigênica , Peptídeos/química , Ligação Proteica , Dobramento de Proteína , Mapeamento de Interação de Proteínas , Estrutura Terciária de Proteína , Saccharomyces cerevisiae/metabolismo , Transdução de Sinais
7.
Phytochemistry ; 55(7): 755-68, 2000 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11190392

RESUMO

From the floral resins of various Clusia species, seven polyisoprenylated benzophenones were isolated. HPLC allowed their quantification in all resins, revealing a distribution of benzophenone derivatives distinct from each other. In some species the staminal oils were collected and oleic, stearic and palmitic acids were the main constituents.


Assuntos
Benzofenonas/isolamento & purificação , Rosales/química , Benzofenonas/química , Cromatografia Líquida de Alta Pressão , Estrutura Molecular , Análise Espectral
8.
Rev. bras. anal. clin ; 27(2): 53-5, 1995. ilus, tab
Artigo em Português | LILACS | ID: lil-269359

RESUMO

O objetivo deste trabalho foi preparar, em condiçöes adequadas, o fármaco (DTPA) marcado com isótopo radioativo para estudos de cinrilografia renal. Além de avaliar a funçäo renal, este fármaco permite diagnosticar, precocemente, alteraçöes que indicam rejeiçäo de tecido, em casos de transplante de rins. Inicialmente, foram realizados experimentos com camundongos para investigar a distribuiçäo biológica do radiofármaco. Os resultados mostraram que, alguns minutos após a administraçäo, os rins apresentavam uma captaçäo de radioatividade. Estes dados e os resultados dos testes de esterilidade, apirogenicidade e pureza radioquímica confirmaram a qualidade do radiofármaco, permitindo o seu emprego em cintilografias de pacientes com comprometimento renal


Assuntos
Animais , Camundongos , Compostos Radiofarmacêuticos/uso terapêutico , Insuficiência Renal Crônica , Pentetato de Tecnécio Tc 99m , Transplante de Rim , Cintilografia/estatística & dados numéricos
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