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1.
Photodiagnosis Photodyn Ther ; 18: 193-197, 2017 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-28238893

RESUMEN

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.


Asunto(s)
Bovinos/parasitología , Daño del ADN/genética , ADN Protozoario/genética , ADN Protozoario/efectos de la radiación , Fotoquimioterapia/métodos , Tritrichomonas foetus/efectos de los fármacos , Tritrichomonas foetus/genética , Animales , ADN Protozoario/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Relación Dosis-Respuesta en la Radiación , Dosis de Radiación , Tritrichomonas foetus/efectos de la radiación
2.
Proteins ; 58(2): 339-53, 2005 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-15562516

RESUMEN

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.


Asunto(s)
Biología Computacional/métodos , Proteínas/química , Proteómica/métodos , Animales , Proteínas Arqueales/química , Proteínas Bacterianas/química , Sitios de Unión , Secuencia Conservada , Bases de Datos de Proteínas , Dimerización , Evolución Molecular , Humanos , Modelos Moleculares , Datos de Secuencia Molecular , Familia de Multigenes , Péptidos/química , Unión Proteica , Pliegue de Proteína , Mapeo de Interacción de Proteínas , Estructura Terciaria de Proteína , Saccharomyces cerevisiae/metabolismo , Transducción de Señal
3.
Phytochemistry ; 55(7): 755-68, 2000 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-11190392

RESUMEN

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.


Asunto(s)
Benzofenonas/aislamiento & purificación , Rosales/química , Benzofenonas/química , Cromatografía Líquida de Alta Presión , Estructura Molecular , Análisis Espectral
4.
Med Biol Eng Comput ; 48(6): 573-7, 2010 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-20390460

RESUMEN

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.


Asunto(s)
Articulación de la Rodilla/fisiología , Artes Marciales/fisiología , Músculo Esquelético/fisiología , Adolescente , Fenómenos Biomecánicos , Electromiografía/métodos , Humanos , Masculino , Procesamiento de Señales Asistido por Computador , Adulto Joven
6.
Braz J Med Biol Res ; 42(5): 433-7, 2009 May.
Artículo en Inglés | MEDLINE | ID: mdl-19377792

RESUMEN

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.


Asunto(s)
ADN Bacteriano/genética , Mutación/genética , Mycobacterium tuberculosis/genética , Tuberculosis Resistente a Múltiples Medicamentos/microbiología , Infecciones Oportunistas Relacionadas con el SIDA/microbiología , Antituberculosos/farmacología , Brasil , Dermatoglifia del ADN , Genotipo , Humanos , Masculino , Pruebas de Sensibilidad Microbiana , Persona de Mediana Edad , Mycobacterium tuberculosis/efectos de los fármacos , Mycobacterium tuberculosis/aislamiento & purificación , Fenotipo , Polimorfismo de Longitud del Fragmento de Restricción
7.
Rev. bras. plantas med ; 16(4): 804-811, oct.-dic. 2014. graf, tab
Artículo en Inglés | LILACS | ID: lil-729887

RESUMEN

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.


Asunto(s)
Aceites Volátiles/química , /farmacología , Química , Ajo/metabolismo , Noxas/efectos adversos , Contaminantes Químicos en Alimentos
8.
Braz. j. med. biol. res ; 42(5): 433-437, May 2009. ilus, tab
Artículo en Inglés | LILACS | ID: lil-511340

RESUMEN

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.


Asunto(s)
Humanos , Masculino , Persona de Mediana Edad , ADN Bacteriano/genética , Mutación/genética , Mycobacterium tuberculosis/genética , Tuberculosis Resistente a Múltiples Medicamentos/microbiología , Infecciones Oportunistas Relacionadas con el SIDA/microbiología , Antituberculosos/farmacología , Brasil , Dermatoglifia del ADN , Genotipo , Pruebas de Sensibilidad Microbiana , Mycobacterium tuberculosis/efectos de los fármacos , Mycobacterium tuberculosis/aislamiento & purificación , Fenotipo , Polimorfismo de Longitud del Fragmento de Restricción
9.
Rev. bras. anal. clin ; 27(2): 53-5, 1995. ilus, tab
Artículo en Portugués | LILACS | ID: lil-269359

RESUMEN

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


Asunto(s)
Animales , Ratones , Radiofármacos/uso terapéutico , Insuficiencia Renal Crónica , Pentetato de Tecnecio Tc 99m , Trasplante de Riñón , Cintigrafía/estadística & datos numéricos
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