RESUMO
Clustered regularly interspaced short palindromic repeats/clustered regularly interspaced short palindromic repeats -associated protein (CRISPR/Cas) has been developed as a precise, efficient, affordable and sensitive nucleic acid detection tool due to its efficient targeted binding ability and programmability. At present, biosensors based on CRISPR-Cas system have shown excellent performance in the detection of nucleic acid of pathogens, which has attracted widespread attention, and is expected to replace the conventional detection methods. This review summarizes the latest research progress of biosensors based on CRISPR/Cas system for detecting nucleic acid of pathogens.
Assuntos
Técnicas Biossensoriais , Sistemas CRISPR-Cas/genética , Ácidos Nucleicos/genéticaRESUMO
Objective To investigate the effect of automatic nucleic acid purifiers QIAsymphony SP and QIAcube in the DNA extraction of samples of trace amount or mixed with inhibitors. Methods Different kinds of purification methods using QIAsymphony SP and QIAcube were applied to extract swabs which contained 30, 100, 150 and 300 cells and other samples which contained six types of inhibitors-heme, humic acid, lard, soil, rust and grease. PCR amplification and STR typing were performed on the extracted DNA templates to compare extracting efficiency and inhibitor removal ability of four different purification methods. Results Different purification methods showed similar extraction effects, 70.83%-100.00% of loci could be detected by amplification of DNA extracted from samples with 30, 100 and 300 cells, and the six types of inhibitors could be removed well. Conclusion The two automatic nucleic acid purifiers have a good inhibitor removal effect. For swabs with only 30 cells, after DNA extraction and amplification, the locus detection rate of samples can still be high, which can meet the requirements of local DNA laboratory work, and realize the standardization construction of the laboratory.
Assuntos
DNA , Impressões Digitais de DNA , Ácidos Nucleicos/genética , Reação em Cadeia da PolimeraseRESUMO
The potential use of urinary nucleic acids as diagnostic markers in prostate cancer (PCa) was evaluated. Ninety-five urine samples and 234 prostate tissue samples from patients with PCa and benign prostatic hyperplasia (BPH) were analyzed. Micro-array analysis was used to identify candidate genes, which were verified by the two-gene expression ratio and validated in tissue mRNA and urinary nucleic acid cohorts. Real-time quantitative polymerase chain reaction (qPCR) was used to measure urinary nucleic acid levels and tissue mRNA expression. The TSPAN13-to-S100A9 ratio was selected to determine the diagnostic value of urinary nucleic acids in PCa (P = 0.037) and shown to be significantly higher in PCa than in BPH in the mRNA and nucleic acid cohort analyses (P < 0.001 and P = 0.013, respectively). Receiver operating characteristic (ROC) analysis showed that the area under the ROC curve was 0.898 and 0.676 in tissue mRNA cohort and urinary nucleic acid cohort, respectively. The TSPAN13-to-S100A9 ratio showed a strong potential as a diagnostic marker for PCa. The present results suggest that the analysis of urine supernatant can be used as a simple diagnostic method for PCa that can be adapted to the clinical setting in the future.
Assuntos
Idoso , Idoso de 80 Anos ou mais , Humanos , Masculino , Pessoa de Meia-Idade , Biomarcadores Tumorais/genética , Calgranulina B/genética , Estudos de Coortes , Ácidos Nucleicos/genética , Análise de Sequência com Séries de Oligonucleotídeos , Próstata/metabolismo , Hiperplasia Prostática/diagnóstico , Neoplasias da Próstata/diagnóstico , RNA Mensageiro/genética , RNA Neoplásico/genética , Curva ROC , Reação em Cadeia da Polimerase em Tempo Real , Tetraspaninas/genéticaRESUMO
We have explored the region around the splice sites of the human intron and exons from the exon-intron database (EID) and located a number of short 6-nucleotide and 7-nucleotide sequences that are relatively common in the regions. These short sequences, we expect play an important role in the selection of the appropriate splicing process. We propose that the external signals via short recognition sequences play the deterministic role in the actual splicing process. We have obtained 50 such sequences each from the exon and intron from the beginning and from the ending and noted a number of common features.
Assuntos
Sequência de Bases , Sítios de Ligação , Sequência Conservada , Bases de Dados Genéticas , Éxons/genética , Humanos , Íntrons/genética , Ácidos Nucleicos/genética , Ácidos Nucleicos/metabolismo , Splicing de RNA , Análise de Sequência de DNA , Spliceossomos/genética , Spliceossomos/metabolismoRESUMO
Introdução: a amplificação de ácido nucleico através da técnica de reaçã em cadeia da polimerase - PCR pode ser útil para o diagnóstico da tuberculose. O objetivo deste trabalho foi padronizar um método molecular para o diagnóstico da TB pulmonar. Material e métodos: iniciadores especificos foram usados para amplificação...
Assuntos
Humanos , Tuberculose Pulmonar , Ácidos Nucleicos/genética , DNA Bacteriano , Reação em Cadeia da Polimerase , Reprodutibilidade dos Testes , Sensibilidade e EspecificidadeRESUMO
O consumo de álcool vem sendo associado a um aumento do risco de câncer e a uma situaçäo de estresse oxidativo. Os metabólitos responsáveis por tais processos pemanecem em discussäo. Neste trabalho, caracterizamos novos metabólitos radicalares do etanol e examinamos suas interações com ácidos nucléicos. Primeiramente, demonstramos que os radicais 1-hidroxietila e 2-hidroxietila produzidos durante a oxidaçäo do etanol por sistemas Fenton alquilam DNA e RNA in vitro produzindo os adutos 8-(1-HE)Gua e 8-(2-HE)Gua, respectivamente. Esses adutos foram sintetizados e caracterizados quimicamente. Também, demonstramos que acetaldeído, o principal metabólito do etanol, é oxidado por sistemas Fenton, peroxinitrito, xantina oxidase, partículas submitocondrias e ratos a radicais acetila e metila...