RESUMEN
Existing detection methods for pathogen nucleic acid detection, such as polymerase chain reaction (PCR), are complicated and expensive to perform. Here, we report a simple and versatile strategy for highly sensitive detection of pathogen nucleic acid based on toehold-mediated strand displacement initiated primer exchange amplification (t-PER). In the presence of the target, the blocked hairpin substrate is released by toehold-mediated strand displacement, which triggers the primer exchange reaction amplification. Then, multiple long tandem-repeat single-strands generated by PER open the molecular beacon to recover the fluorescence signal. The t-PER protocol also successfully directly detected human papilloma virus from clinical cervical swab samples, with consistent results compared to real time-polymerase chain reaction (RT-PCR). Moreover, the versatility and clinical feasibility of this method was further confirmed by measuring Epstein-Barr virus, hepatitis B virus, and Ureaplasma urealyticum from different clinical samples (serum samples and urine samples). This simple platform enabled specific and sensitive detection of pathogen nucleic acid in a format that might hold great potential for point-of-care infection diagnosis.
Asunto(s)
Técnicas Biosensibles , Infecciones por Virus de Epstein-Barr , Ácidos Nucleicos , Técnicas Biosensibles/métodos , Herpesvirus Humano 4 , Humanos , Límite de Detección , Técnicas de Amplificación de Ácido Nucleico/métodosRESUMEN
Extracellular vesicle-associated miRNAs (EV-miRNAs) are emerging as a new type of noninvasive biomarker for disease diagnosis. Their relatively low abundance, however, makes accurate detection challenging. Here, we designed a DNA nanowire guided-catalyzed hairpin assembly (NgCHA) nanoprobe for profiling EV-miRNAs. NgCHA showed high penetrability to EVs, which allowed rapid delivery of the probes into EVs. In the presence of targeted miRNAs within EVs, a fluorescent signal could be generated and amplified by confining the catalytic hairpin assembly system within the nanowires, thus greatly enhancing the analytical sensitivity. We showed that EV-miRNAs from various cell lines could be accurately quantified by NgCHA in situ. By using a four-EV-miRNA panel, this platform can identify patients with breast cancer at an early stage with 95.2% sensitivity and 86.7% specificity. Its applications for risk assessment as well as cancer type prediction were also successfully demonstrated. This platform is sensitive, low-cost, and simple compared with current methods. It may thus serve as a promising tool for the noninvasive diagnosis and monitoring of cancers and other diseases through EV-miRNA profiling.
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MicroARN Circulante , Vesículas Extracelulares , MicroARNs , Nanocables , Catálisis , MicroARN Circulante/metabolismo , ADN/metabolismo , Vesículas Extracelulares/metabolismo , Humanos , MicroARNs/genéticaRESUMEN
BACKGROUNDS: Diabetic nephropathy (DN) is one of the most important clinical complications of diabetes mellitus (DM) and is the most common cause of end-stage renal disease. Currently, there is no highly effective medicine that can prevent, halt, or reverse the progressive course of DN. Initial clinical data showed that Tripterygium glycosides (TGs), a traditional Chinese medicine, can decrease proteinuria in patients with DN. OBJECTIVES: The objective of the present study is to investigate the efficacy and safety of TGs for the treatment of DN through meta-analysis of randomized controlled trials (RCTs). METHODS: All RCTs of TGs for DN were collected from The China National Knowledge Infrastructure (CNKI), PubMed, Web of Science, Wanfang Data, Chinese Biomedical Literature Database (CBM), China Science and Technology Journal Database (VIP) by setting the study inclusion and elimination standards. Two reviewers evaluated the quality of the trials and extracted the data independently. RevMan 5.4 software was used for meta-analyses. The primary outcome was a change in 24-hours urinary total protein (24 h TUP). RESULTS: 26 RCTs with 1824 participants were identified. Studies were assessed using the Cochrane risk of bias tool. The overall effects showed that TGs was compared with the controls, TGs showed significant effects in reducing 24 h TUP [WMD = -0.84, 95 % CI (-1.09, -0.59)], elevating serum albumin [WMD = 2.88, 95 % CI (1.87, 3.90)], and the total efficiency [OR = 4.08, 95 % CI (2.37, 7.04)]. This effect was consistent across the subgroups of period of intervention. CONCLUSIONS: The present research showed that TGs was significantly associated with improvement of renal function in patients with DN. TGs offers a novel approach to the treatment of DN, more high-quality RCTs are needed for a better understanding of the role of TGs in DN therapy.
Asunto(s)
Nefropatías Diabéticas/tratamiento farmacológico , Glicósidos/uso terapéutico , Tripterygium , Sesgo , Nitrógeno de la Urea Sanguínea , Creatinina/sangre , Nefropatías Diabéticas/fisiopatología , Glicósidos/efectos adversos , Humanos , Proteinuria/tratamiento farmacológico , Ensayos Clínicos Controlados Aleatorios como AsuntoRESUMEN
This paper reported a headspace gas chromatography (HS-GC) for the determination of denitrifying enzyme activity in soil samples. It was based on measuring the NO2 signal in a set of closed/air-free vials containing soil samples that incubated at the designated conditions. The results showed that the method has a good measurement precision (RSD < 5.0%) and reasonable accuracy for determining the denitrifying enzyme activity in soil samples. It is simple and efficient, and very suitable to be used in batch sample analysis.
Asunto(s)
Cromatografía de Gases/métodos , Desnitrificación , Enzimas/metabolismo , Suelo/química , Calibración , Dióxido de Nitrógeno/análisis , Tamaño de la Muestra , Factores de TiempoRESUMEN
OBJECTIVE: To study the dynamic changes of tuberculosis related cytokines among patients during the different courses of treatment, and to analyze their influences on the development and prognoses of tuberculosis. METHODS: All patients with active tuberculosis were enrolled from Guangzhou, Shenzhen and Foshan TB control institutes. There were a total of 68 cases, 36 males and 32 females, aged 19 to 50 years [ average (30±9) years]. All the TB patients received standard chemotherapy regimen of anti-tuberculosis, and were divided into 2 groups: one completed treatment group (cured or clinically cured 38 cases) and 1 uncompleted treatment group (treatment failure or need to extend treatment, 30 cases). Peripheral blood serum at 0, 2, 6 month during the treatment from 68 tuberculosis patients were collected, and the concentration of IFN-γ,IL-4,IL-17,TGF-ß,TNF-α and IL-10 were detected by ELISA tests. RESULTS: The concentration of IFN-γ, TGF-ß and IL-4 in all enrolled patients showed significant decrease (from 23.2 ng/L to 22.3 ng/L, from 169.1 ng/L to 123.2 ng/L; 65.0 ng/L to 31.9 ng/L) (t=2.67, 2.35 and 3.41, P<0.05) along with the extension of treatment. IL-10 increased significantly (12.9 ng/L) in the uncompleted treatment group but declined significantly (5.38 ng/L) (P<0.05) in the completed treatment group at the end of 6 month. Meanwhile, IL-4 decreased significantly (P<0.05) in the completed treatment group but no significant changes were observed in the uncompleted treatment group. Th1/Th2 (IFN-γ/IL-4) raised gradually in the completed treatment group (0 month <2 month <6 month, t=6.32, 6.03 and 5.85, P<0.05), while it was only at 6 month in the uncompleted treatment group (0 month <6 month, t=3.7, P<0.05). And the ratio of Th1/Th2 in the completed treatment group was significantly higher than that in the uncompleted group treatment (P<0.05). CONCLUSION: It suggests that the changes of Th1 cytokines (IFN-γ, TGF-ß) and the Th1/Th2 balance play an important role in the pathogenesis, development and prognosis of TB. The suppression of IFN-γ, TGF-ß or Th1/Th2 balance may be an important factor influencing the prognosis of TB.