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1.
Einstein (Säo Paulo) ; 21: eAO0109, 2023. tab, graf
Artículo en Inglés | LILACS-Express | LILACS | ID: biblio-1440060

RESUMEN

ABSTRACT Objective To investigate the expression of human papillomavirus (HPV), p16, p53, and p63 in non-schistosomiasis-related squamous cell carcinoma of the bladder and to develop an accurate and automated tool to predict histological classification based on clinicopathological features. Methods Twenty-eight patients with primary bladder pure squamous cell carcinoma who underwent cystectomy or transurethral resection of bladder tumor (TURBT) for bladder cancer between January 2011 and July 2017 were evaluated. Clinical data and follow-up information were obtained from medical records. Formalin-fixed, paraffin-embedded surgical specimens were used for immunohistochemical staining for p16, p53, and p63. Human papillomavirus detection was evaluated by PCR. Statistical analysis was performed, and statistical significance was set at p<0.05. Finally, decision trees were built to classify patients' prognostic features. Leave-one-out cross-validation was used to test the generalizability of the model. Results Neither direct HPV detection nor its indirect marker (p16 protein) was identified in most cases. The absence of p16 was correlated with less aggressive histological grading (p=0.040). The positive p16 staining detection found only in pT1 and pT2 cases in our sample suggests a possible role for this tumor suppressor protein in the initial stages of bladder squamous cell carcinoma. The decision trees constructed described the relationship between clinical features, such as hematuria/dysuria, the level of tumor invasion, HPV status, lymphovascular invasion, gender, age, compromised lymph nodes, and tumor degree differentiation, with high classification accuracy. Conclusion The algorithm classifier approach established decision pathways for semi-automatic tumor histological classification, laying the foundation for tailored semi-automated decision support systems for pathologists.

2.
Mem. Inst. Oswaldo Cruz ; 115: e190498, 2020. tab, graf
Artículo en Inglés | LILACS, SES-SP | ID: biblio-1135282

RESUMEN

BACKGROUND Biomphalaria glabrata snails are widely distributed in schistosomiasis endemic areas like America and Caribe, displaying high susceptibility to infection by Schistosoma mansoni. After the availability of B. glabrata genome and transcriptome data, studies focusing on genetic markers and small non-coding RNAs have become more relevant. The small RNAs have been considered important through their ability to finely regulate the gene expression in several organisms, thus controlling the functions like cell growth, metabolism, and susceptibility/resistance to infection. OBJECTIVE The present study aims on identification and characterisation of the repertoire of small non-coding RNAs in B. glabrata (Bgl-small RNAs). METHODS By using small RNA sequencing, bioinformatics tools and quantitative reverse transcription polymerase chain reaction (RT-qPCR), we identified, characterised, and validated the presence of small RNAs in B. glabrata. FINDINGS 89 mature miRNAs were identified and five of them were classified as Mollusk-specific. When compared to model organisms, sequences of B. glabrata miRNAs showed a high degree of conservation. In addition, several target genes were predicted for all the mature miRNAs identified. Furthermore, piRNAs were identified in the genome of B. glabrata for the first time. The B. glabrata piRNAs showed strong conservation of uridine as first nucleotide at 5' end, besides adenine at 10th position. Our results showed that B. glabrata has diverse repertoire of circulating ncRNAs, several which might be involved in mollusk susceptibility to infection, due to their potential roles in the regulation of S. mansoni development. MAIN CONCLUSIONS Further studies are necessary in order to confirm the role of the Bgl-small RNAs in the parasite/host relationship thus opening new perspectives on interference of small RNAs in the organism development and susceptibility to infection.


Asunto(s)
Animales , Schistosoma mansoni/fisiología , Biomphalaria/genética , Biomphalaria/parasitología , Esquistosomiasis mansoni/fisiopatología , Esquistosomiasis mansoni/genética , MicroARNs/genética , Predisposición Genética a la Enfermedad/genética , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , ARN Interferente Pequeño , Secuenciación de Nucleótidos de Alto Rendimiento , Interacciones Huésped-Parásitos
3.
Mem. Inst. Oswaldo Cruz ; 115: e190378, 2020. tab, graf
Artículo en Inglés | LILACS, SES-SP | ID: biblio-1135284

RESUMEN

BACKGROUND Key genes control the infectivity of the Schistosoma haematobium causing schistosomiasis. A method for understanding the regulation of these genes might help in developing new disease strategies to control schistosomiasis, such as the silencing mediated by microRNAs (miRNAs). The miRNAs have been studied in schistosome species and they play important roles in the post-transcriptional regulation of genes, and in parasite-host interactions. However, genome-wide identification and characterisation of novel miRNAs and their pathway genes and their gene expression have not been explored deeply in the genome and transcriptome of S. haematobium. OBJECTIVES Identify and characterise mature and precursor miRNAs and their pathway genes in the S. haematobium genome. METHODS Computational prediction and characterisation of miRNAs and genes involved in miRNA pathway from S. haematobium genome on SchistoDB. Conserved domain analysis was performed using PFAM and CDD databases. A robust algorithm was applied to identify mature miRNAs and their precursors. The characterisation of the precursor miRNAs was performed using RNAfold, RNAalifold and Perl scripts. FINDINGS We identified and characterised 14 putative proteins involved in miRNA pathway including ARGONAUTE and DICER in S. haematobium. Besides that, 149 mature miRNAs and 131 precursor miRNAs were identified in the genome including novel miRNAs. MAIN CONCLUSIONS miRNA pathway occurs in the S. haematobium, including endogenous miRNAs and miRNA pathway components, suggesting a role of this type of non-coding RNAs in gene regulation in the parasite. The results found in this work will open up a new avenue for studying miRNAs in the S. haematobium biology in helping to understand the mechanism of gene silencing in the human parasite Schistosome.


Asunto(s)
Humanos , Animales , Schistosoma haematobium/genética , Esquistosomiasis/parasitología , Regulación de la Expresión Génica/genética , Biología Computacional/métodos , MicroARNs/genética , Análisis de Secuencia de ARN , Transcriptoma/genética
4.
Biosci. j. (Online) ; 35(1): 260-266, jan./fev. 2019. tab
Artículo en Inglés | LILACS | ID: biblio-1048579

RESUMEN

Infertility or subfertility in bovine males may be related to spermatic microRNAs (miRNAs), whose function seems to be associated with the regulation of gene expression, degradation orstorage of messenger RNAs (mRNAs) for later translation into early embryonic development. Thus, the purpose of this study was to identify differentially expressed miRNAs in semen samples from bulls (Bos taurus) with low and high efficiency in the in vitro embryo production (IVEP) and to evaluate if they can be used as markers of semen efficiency for IVEPs. In order to identify miRNA markers of semen efficiency in thein vitro embryo production, eight semen samples from each animal, one bull with high and two bulls with low efficiency in IVEPs were used to perform the RNAseq technique for miRNAs. Initially the samples were washed with PBS to remove the extender semen and subsequently were submitted to RNA extraction protocols performed according to procedures described by mirVana™ miRNA Isolation Kit. Then, the amplification of the miRNAs was carried out, not to mention the preparation of the library (Ion Total RNA-Seq Kit v2), the PCR emulsion reaction, enrichment, as well as the injection of the sample on the chip by the Ion Chef equipment. The sequencing was done on Ion Proton equipment. The comparison between the samples was established using two methodologies for searching for targets to increase the robustness of the analytical procedure: the miRanda program using as cutoff minimum free energy of the hybridization -20 kcal/Mol, 100% of identity between nucleotides 2 and 8 of the miRNA, and the RNAhybrid program, using as cutoff minimum free energy of hybridization -20 kcal/mol. In sum, 1306 miRNAs were identified in the samples. The bta-miR-380-5p, bta-miR-155, bta-miR-30c and bta-miR-34a genes were identified by the Bioinformatics as being strongly differentially expressed between the groups, indicating that these genes may present themselves as possible efficiency markers. However, it has become clear that there is no single miRNA that marks different types and causes of fertility problems.


A infertilidade ou subfertilidade em machos bovinos pode estar relacionada a microRNAs espermáticos (miRNAs), cuja função parece estar associada à regulação da expressão gênica, degradação ou armazenamento de RNAs mensageiros (mRNAs), para posterior tradução no desenvolvimento embrionário inicial. Assim, o objetivo deste estudo foi identificar miRNAs diferencialmente expressos em amostras de sêmen de touros (Bos taurus) com baixa e alta eficiência na produção in vitro de embriões (PIVE) e avaliar se eles podem ser utilizados como marcadores de eficiência do sêmen em PIVEs. Para identificar miRNA marcadores da eficiência de sêmen em PIVE, oito amostras de sêmen de cada animal, sendo um touro com alto e dois touros com baixa eficiência, foram utilizados para realizar a técnica de RNAseq para miRNAs. Inicialmente as amostras foram lavadas com PBS para remover o diluente do sêmen e, posteriormente, foram submetidas a protocolos de extração de RNA realizados de acordo com os procedimentos descritos pelo Kit de isolamento de miRNA mirVana ™. Em seguida, foi realizada a amplificação dos miRNAs, a preparação da biblioteca (Ion RNA-Seq Kit v2), a reação de emulsão de PCR, enriquecimento e a injeção das amostras no chip apropriado utilizando o equipamento Ion. Chef. O sequenciamento foi realizado no equipamento Ion Proton. A comparação entre as amostras foi estabelecida utilizando duas metodologias de busca de alvos para aumentar a robustez do procedimento analítico: o programa miRanda utilizando como valor de corte a energia mínima livre de hibridização -20 kcal / Mol e 100% de identidade entre os nucleotídeos 2 e 8 do miRNA, e o programa RNAhybrid, utilizando como valor de corte a energia mínima livre de hibridização -20 kcal / mol. Em suma, 1306 miRNAs foram identificados nas amostras. Os genes bta-miR-380-5p, bta-miR-155, bta-miR-30c e bta-miR-34a foram identificados pela bioinformática como sendo fortemente diferencialmente expressos entre os grupos, indicando que esses genes podem se apresentar como possíveis marcadores de eficiência. No entanto, ficou claro que não existe um único miRNA que marque diferentes tipos e causas de problemas de fertilidade.


Asunto(s)
ARN , Bovinos , Investigaciones con Embriones , Infertilidad
5.
Mem. Inst. Oswaldo Cruz ; 113(6): e170542, 2018. tab, graf
Artículo en Inglés | LILACS | ID: biblio-894932

RESUMEN

BACKGROUND Infection with Zika virus (ZIKV) manifests in a broad spectrum of disease ranging from mild illness to severe neurological complications and little is known about Zika immunopathogenesis. OBJECTIVES To define the immunologic biomarkers that correlate with acute ZIKV infection. METHODS We characterized the levels of circulating cytokines, chemokines, and growth factors in 54 infected patients of both genders at five different time points after symptom onset using microbeads multiplex immunoassay; comparison to 100 age-matched controls was performed for statistical analysis and data mining. FINDINGS ZIKV-infected patients present a striking systemic inflammatory response with high levels of pro-inflammatory mediators. Despite the strong inflammatory pattern, IL-1Ra and IL-4 are also induced during the acute infection. Interestingly, the inflammatory cytokines IL-1β, IL-13, IL-17, TNF-α, and IFN-γ; chemokines CXCL8, CCL2, CCL5; and the growth factor G-CSF, displayed a bimodal distribution accompanying viremia. While this is the first manuscript to document bimodal distributions of viremia in ZIKV infection, this has been documented in other viral infections, with a primary viremia peak during mild systemic disease and a secondary peak associated with distribution of the virus to organs and tissues. MAIN CONCLUSIONS Biomarker network analysis demonstrated distinct dynamics in concurrence with the bimodal viremia profiles at different time points during ZIKV infection. Such a robust cytokine and chemokine response has been associated with blood-brain barrier permeability and neuroinvasiveness in other flaviviral infections. High-dimensional data analysis further identified CXCL10, a chemokine involved in foetal neuron apoptosis and Guillain-Barré syndrome, as the most promising biomarker of acute ZIKV infection for potential clinical application.


Asunto(s)
Humanos , Quimiocina CXCL10/sangre , Infección por el Virus Zika/complicaciones , Expresión Génica , Quimiocinas/inmunología , Infección por el Virus Zika/inmunología
6.
Rev. bras. cancerol ; 58(2): 241-249, abr.-jun. 2012. tab
Artículo en Portugués | LILACS | ID: lil-647229

RESUMEN

Introdução: Nas últimas décadas, o câncer ganhou uma dimensão maior, convertendo-se em um evidente problema de saúde pública mundial. A Organização Mundial da Saúde estimou que, no ano 2030, podem-se esperar 27 milhões de casos incidentes de câncer e 17 milhões de mortes por câncer. Frente a esse cenário alarmante, a mineração de dados traz métodos e ferramentas capazes de auxiliar na construção de conhecimentos mais incisivos sobre o câncer. Objetivo: Este trabalho tem por objetivo aplicar cinco métodos tradicionais da mineração de dados à base de dados NCI60, construída com dados oriundos de experimentos de microarray, com níveis de expressão de 1.000 genes agrupados em nove classes de câncer. Método: Foram utilizados neste trabalho os métodos J48, Random Forest, PART , IBK e Naive Bayes, pertencentes ao ambiente Weka, bem tradicionais na mineração de dados. Devido ao baixo número de registros para determinadas classes, utilizou-se, na validação dos resultados obtidos pelos classificadores, o 3-fold cross validation. Resultados: O classificador que obteve a melhor precisão foi o IBK, enquanto os classificadores J48 e PART conseguiram diminuir o conjunto de genes drasticamente, construindo conhecimento de alto nível na forma de árvores ou regras. Conclusão: Os resultados obtidos neste trabalho podem ser utilizados como ferramentas que visam a auxiliar no enfrentamento do câncer, podendo ser utilizadas na classificação de novos casos ou para se conhecer, cada vez mais, as relações gene/gene e gene/câncer.


Asunto(s)
Humanos , Masculino , Femenino , Biología Computacional , Bases de Datos como Asunto , Expresión Génica , Oncogenes/genética
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