Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 7 de 7
Filtrar
Añadir filtros








Intervalo de año
1.
Tissue Engineering and Regenerative Medicine ; (6): 677-683, 2016.
Artículo en Inglés | WPRIM | ID: wpr-647650

RESUMEN

Tendon and ligament (T/L) have been known to be obviously different from each other in tissue level. However, due to the overlapping gene markers, distinction in cellular level has not been clearly verified yet. Recently, the use of nuclear magnetic resonance (NMR) spectroscopy has shown the potential to detect biological markers in cellular level. Therefore, in this study we applied a non-invasive technique based on NMR spectroscopy to establish biomarkers to distinguish between T/L fibroblasts. In addition the cellular morphologies and gene expression patterns were also investigated for comparison through optical microscopy and real-time polymerase chain reaction (PCR). No difference was observed from morphology and real-time PCR results, either as expected. However, we found clear differences in their metabolomic spectra using ¹H NMR spectroscopy. The calculated integral values of fatty acids (with chemical shifts at ~0.9, 1.26, 1.59, 2.05, 2.25, and 2.81 ppm), lactate (~1.33 ppm), and leucine (~2.72 ppm) were significantly different between the two types of fibroblasts. To be specific tendon group exhibited higher level of the metabolite than ligament group. In conclusion, in-cell metabolomic evaluation by NMR technique used in this study is believed to provide a promising tool in distinguishing cell types, especially T/L cells, which cannot be classified by conventional biological assays.


Asunto(s)
Bioensayo , Biomarcadores , Ácidos Grasos , Fibroblastos , Expresión Génica , Genes Sobrepuestos , Ácido Láctico , Leucina , Ligamentos , Espectroscopía de Resonancia Magnética , Metabolómica , Microscopía , Reacción en Cadena en Tiempo Real de la Polimerasa , Análisis Espectral , Tendones
2.
Rio de Janeiro; s.n; 2015. xvii,198 p. ilus, tab, graf.
Tesis en Inglés, Portugués | LILACS | ID: lil-774264

RESUMEN

A inferência de homologia entre organismos é uma atividade da genômicacomparativa que possibilita compreender melhor a relação entre os mesmos e, porconseguinte, sua distância evolutiva. Especificamente, a identificação de genesortólogos, ou seja, aqueles que têm sua origem em um ancestral comum, permiteoferecer melhorias na anotação funcional de genes, uma vez que genes ortólogostendem a ter sua função conservada.Com a crescente disponibilidade de genomas através de técnicas de NGS, aconstrução e atualização de bases de dados de ortólogos representam um desafioconstante, pois demandam o estudo e identificação das relações entre os genes detais organismos, em um volume de dados cada vez mais extenso e a um custocomputacional cada vez mais elevado.Nesta tese propomos a solução para nuvem computacional elastic-OrthoSearch, umworkflow científico de genômica comparativa inspirado no OrthoSearch, responsávelpela inferência de homologia entre organismos com o uso de abordagem baseadaem melhores hits recíprocos e perfis de Markov.Também propomos uma metodologia para criação de bases de ortólogos construídaatravés do reuso do OrthoSearch. Esta metodologia mostrou-se capaz de alavancara oferta de grupos ortólogos e assim auxiliar, por exemplo, na identificação de alvosde protozoários...


Homology inference among organisms is a comparative genomics tasks which allowsfor a better understanding on how such organisms are related to each other and ontheir evolutionary distance. Specifically, the identification of orthologous genes –those who share a common ancestor – allows for functional gene annotationimprovements, as orthologous genes tend to preserve their functions.The increasing amount of genomic data provided by the NGS techniques makes theorthologous databases’ building and update processes a challenging task. It requiresthe identification and study of the organisms’ genes relationships, in an extensivedata volume and at an increasing computational cost.In this thesis we propose elastic-OrthoSearch, a cloud-enabled comparativegenomics scientific workflow, derived from OrthoSearch. It aims at providinghomology inference among organisms, in a reciprocal best hits and Markov profilesapproach.We also propose an improved orthologous database creation methodology built ontop of OrthoSearch. Such methodology has shown means to offer a broaderorthologous groups dataset, which could in turn aid on Protozoa target identification...


Asunto(s)
Animales , Genes Sobrepuestos , Genoma de Protozoos , Genómica , Enfermedades Desatendidas , Flujo de Trabajo , Biología Computacional
3.
Arq. bras. med. vet. zootec ; 66(5): 1367-1375, Sep-Oct/2014. tab, graf
Artículo en Portugués | LILACS | ID: lil-729755

RESUMEN

A diversificação da produção industrial de alimentos de origem suína e o intercâmbio comercial de animais e seus derivados destinados ao consumo humano podem ser importantes disseminadores de sorovares de Salmonella spp. na cadeia alimentar. Objetivou-se avaliar em 86 cepas de Salmonella spp., isoladas em granja de terminação e no abate de suínos, a ocorrência de três genes de virulência (invA, agfA e lpfA), bem como a similaridade genética entre elas. A ocorrência do gene invA foi verificada em 100% das amostras. O gene lpfA foi detectado em 80,23% (69/86) das cepas, não foi detectado em S. Panama e estava presente em todas as cepas de S. Infantis. O gene agfA foi detectado em 63,95% (55/86) das amostras. S. Agona apresentou positividade para todos os genes de virulência estudados. A análise de homologia entre as cepas agrupou os diferentes sorovares em clusters. A similaridade foi independente do local de isolamento, o que demonstra a presença de clones ao longo da cadeia de produção e a existência de multiplicidade de fontes para a infecção dos animais, como a ração, e a contaminação cruzada das carcaças. A pesquisa de genes de virulência e a avaliação da proximidade gênica permitem a caracterização e um maior entendimento sobre cepas de Salmonella circulantes na cadeia produtiva de suínos e, assim, podem subsidiar medidas de controle durante o processo produtivo com o objetivo de garantir a saúde do consumidor...


The diversification of industrial food production of swine origin and trade of animals and their derivatives for human consumption may be important disseminators of serovars of Salmonella spp. in the food chain. This study aimed to evaluate 86 strains of Salmonella spp. isolated form in the finishing and slaughter of pigs, the occurrence of three virulence genes (invA, agfa and lpfA), as well as the genetic similarity between them. The occurrence of gene invA was observed in 100% of the samples. The gene lpfA was detected in 80.23% (69/86) strains and is not detected in S. Panama, but present in all strains of S. Infantis. The gene agfA was detected in 63.95% (55/86). S. Agona was positive for all virulence genes studied. The analysis of homology between the different serovars grouped the isolates in clusters. The similarity was regardless of the location of isolation, demonstrating the presence of clones along the production chain and that there are multiple sources for the infection of animals, such as feed, and cross-contamination of carcasses. A survey of virulence genes and evaluation of gene proximity allow characterization and better understanding of Salmonella strains circulating in the pig production chain, thus being able to support control measures during the production process in order to ensure consumer health...


Asunto(s)
Animales , Genes Sobrepuestos , Porcinos , Salmonella/inmunología , Salmonella/virología , Indicadores de Contaminación/prevención & control , Industria de la Carne , Virulencia , Factores de Virulencia
4.
Diabetes & Metabolism Journal ; : 356-365, 2014.
Artículo en Inglés | WPRIM | ID: wpr-59599

RESUMEN

BACKGROUND: Peroxisome proliferator-activated receptor-gamma (PPAR-gamma) agonist has a wide-ranging influence on multiple components of metabolic syndrome. The Otsuka Long-Evans Tokushima Fatty (OLETF) rat is a useful animal model of metabolic syndrome. To determine genes related to metabolic syndrome, we examined overlapping genes that are simultaneously decreased by PPAR-gamma agonists and increased in OLETF rats using microarrays in two different models. METHODS: In the first microarray analysis, PPAR-gamma agonist-treated db/db mice were compared to standard diet-fed db/db mice. In the second microarray analysis, OLETF rats were compared to Long-Evans Tokushima Otsuka (LETO) rats (control of OLETF rats). RESULTS: Among the overlapping genes, in the present study, we validated that lipocalin-2 expression was significantly decreased in the visceral adipose tissue of PPAR-gamma agonist-treated db/db mice compared to standard diet-fed db/db mice and increased in OLETF rats compared to LETO rats using real time reverse transcription polymerase chain reaction. Furthermore, we showed for the first time that lipocalin-2 expression was significantly increased in the visceral adipose tissues of obese humans compared with nonobese humans. In addition, the expression level of lipocalin-2 in human visceral adipose tissue had a significant positive correlation with body mass index, serum interleukin-6, adipocyte fatty acid binding protein levels, and white blood cell count. CONCLUSION: Lipocalin-2 was confirmed to be a significant adipokine affected by PPAR-gamma agonist and obesity in the present study. Also, for the first time in human visceral adipose tissue, it was determined that the expression of lipocalin-2 from obese humans was significantly increased and correlated with circulating inflammatory markers.


Asunto(s)
Animales , Humanos , Ratones , Ratas , Adipocitos , Adipoquinas , Índice de Masa Corporal , Proteínas Portadoras , Genes Sobrepuestos , Interleucina-6 , Grasa Intraabdominal , Recuento de Leucocitos , Análisis por Micromatrices , Modelos Animales , Obesidad , Peroxisomas , Reacción en Cadena de la Polimerasa , PPAR gamma , Ratas Endogámicas OLETF , Transcripción Reversa , Transcriptoma
5.
Rio de Janeiro; s.n; 2012. xi,134 p. ilus, tab.
Tesis en Portugués | LILACS | ID: lil-750248

RESUMEN

Esta tese descreve o projeto conceitual do sistema de banco de dados ProteinWorldDB (PWDB). Um ponto importante da proposta do PWDB é permitir a construção de consultas e procedimentos no domínio da genômica comparativa sem a necessidade de comparação de sequências. Além disso, o PCG comparou milhões de sequências de proteína, incluindo o conjunto proteico total de centenas de genomas completos, utilizando programação dinâmica, e não um método heurístico, para os cálculos de similaridade. A estratégia do PCG, assim como a genômica, está fundamentada no conhecimento de que sequências biológicas por si só são pouco informativas; elas precisam ser analisadas a partir de um enfoque comparativo para a inferência de homologia. A comparação de sequências de diferentes organismos introduz uma perspectiva evolutiva ao processo, e o estudo comparativo de genomas completos pode ampliar a escala do conhecimento de um único processo biológico para o de sistemas biológicos complexos em células e organismos. Para responder eficientemente questões dessa natureza, o esquema conceitual apresentado associa bases de dados biológicos de referência aos índices de similaridade já pré-calculados e armazenados pelo PCGUtilizando um formato gráfico de fácil compreensão para representar conceitos e relacionamentos (diagrama ER), o esquema foi proposto para facilitar o planejamento de consultas e procedimentos por pesquisadores da área de genômica (sem conhecimento de linguagens de bancos de dados), assim como guiar o desenvolvimento e a implementação física do PWDB por profissionais da área de computação. Alguns exemplos são apresentados com o objetivo de demonstrar a utilização do esquema conceitual para a especificação de consultas e procedimentos, mesmo antes da existência de um esquema lógico...


This thesis describes the conceptual design of the database system ProteinWorldDB(PWDB). An important point of the PWDB proposal is to allow the construction of queriesand procedures in the field of comparative genomics without the need for sequencecomparison. Moreover, the PCG compared millions of protein sequences, including theentire set of proteins from hundreds of complete genomes using dynamic programming,rather than a heuristic method, for calculating similarityPCG‘s strategy, like that of genomic studies in general, is grounded in the knowledgethat biological sequences alone are uninformative. They need to be analyzed from acomparative approach to infer homology. The comparison of sequences from differentorganisms introduces an evolutionary perspective to the process and the comparativestudy of complete genomes can expand our knowledge from a single biological processall the way to complex biological systems in cells and organisms. To efficiently answerquestions of this nature, the conceptual schema links selected international referencebiological databases to similarity indexes already precomputed and stored by the PCG.By using an easily understandable graphic format to represent concepts andrelationships (ER diagram), the schema was proposed to help the design of queries andprocedures by genomic researchers (who may not have knowledge of databaselanguages) as well as to guide the development and physical implementation of thesystem by developers. Some examples are presented to demonstrate the use of theconceptual schema for specifying queries and procedures, even before the existence ofa logical schema. The schema can be easily extended. Additional modules can be inserted/removed toinclude other protein sequences comparisons projects that may benefit from theinformation provided by the schema´s central module. Likewise, new databases specificto different areas (-omics, for example) can be cross-referenced to the schema...


Asunto(s)
Humanos , Biología Computacional , Bases de Datos de Ácidos Nucleicos , Genes Sobrepuestos , Genómica/clasificación
6.
Journal of Korean Medical Science ; : 433-437, 2005.
Artículo en Inglés | WPRIM | ID: wpr-53831

RESUMEN

Disappearance of hepatitis B surface antigens (HBsAg) in chronic hepatitis B usually indicates clearance of hepatitis B virus (HBV) infection. However, false HBsAg negativity with mutations in pre-S2 and 'a' determinant has been reported. It is also known that YMDD mutations decrease the production of HBV and escape detection of serum HBsAg. Here, we report overlapping gene mutations in a patient with HBsAg loss during the lamivudine therapy. After 36 months of lamivudine therapy in a 44-yrold Korean chronic hepatitis B patient, serum HBsAg turned negative while HBV DNA remained positive by a DNA probe method. Nucleotide sequence of serum HBV DNA was compared with the HBV genotype C subtype adr registered in NCBI AF 286594. Deletion of nucleotides 23 to 55 (amino acids 12 to 22) was identified in the pre-S2 region. Sequencing of the 'a' determinant revealed amino acid substitutions as I126S, T131N, M133T, and S136Y. Methionine of rtM204 in the P gene was substituted for isoleucine indicating YIDD mutation (rtM204I). We identified a HBV mutant composed of pre-S2 deletions and 'a' determinant substitutions with YMDD mutation. Our result suggests that false HBsAg negativity can be induced by combination of overlapping gene mutations during the lamivudine therapy.


Asunto(s)
Adulto , Humanos , Masculino , Secuencia de Aminoácidos , Fármacos Anti-VIH/uso terapéutico , Secuencia de Bases , Estudio Comparativo , Análisis Mutacional de ADN , ADN Viral/sangre , ADN Polimerasa Dirigida por ADN/genética , Eliminación de Gen , Genes Sobrepuestos/genética , Antígenos de Superficie de la Hepatitis B/sangre , Virus de la Hepatitis B/genética , Hepatitis B Crónica/sangre , Lamivudine/uso terapéutico , Datos de Secuencia Molecular , Mutación , Precursores de Proteínas/genética , Alineación de Secuencia , Homología de Secuencia de Aminoácido , Homología de Secuencia de Ácido Nucleico , Proteínas Virales/genética
7.
Braz. j. microbiol ; 31(1): 20-24, jan.-mar. 2000. ilus, tab
Artículo en Inglés | LILACS | ID: lil-306360

RESUMEN

Yersina pestis, the etiologic agent of plague, harbors three well-characterized plasmids: pFra (90-110kb), pYV (70kb) and pPst (9.5kb). Furthermore, some extra-cryptic DNA bands have been observed in a number of wild strains from several foci of the world. Additional bands have also been reported in Brazilian strains. Looking for any relationship among these cryptic DNA bands and the three-prototypical plasmids, we analyzed twelve strains displaying different plasmid content. The DNA bands were hybridized by southern blot with probes directed at the genes cafl, lcrV and 'pla' located respectively on the plasmids pFra, pYV and pPst. The probes were constructed by PCR amplification and labeled with digoxigenin. The Pla probe hybridized with its target (pPst) and with bands of about 35 kb suggesting some homology among them. The Cafl probe hybridized with the target (pFra) as well as with higher bands. The LcrV also hybridized with the target (pYV) and both with the bands higher than pFra and the bands between pFra and pYV. These results suggest that the large-cryptic bands could represent some rearrangement, open circular or linearized forms of the pFras and pYV plasmids.


Asunto(s)
Sondas de ADN , Genes , Genes Sobrepuestos , Técnicas In Vitro , Plásmidos/genética , Plásmidos/aislamiento & purificación , Yersinia pestis , Métodos de Análisis de Laboratorio y de Campo , Virulencia
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA