RESUMO
BACKGROUND: Alveolar echinococcosis (AE) is a serious parasitic disease caused by the larvae of Echinococcus multilocularis. It is the less common but substantially more deadly of the 2 major echinococcosis diseases that can occur globally but are concentrated in central Asia. METHODS: We analyzed parasite circulating cell-free DNA (cfDNA) in 149 plasma samples using a DNA sequencing-based method (105 AE, 16 cystic echinococcosis, 4 liver cancer, 4 gallstones, and 20 healthy volunteers). After identifying the Echinococcus-specific cfDNA (Em-cfDNA) sequences in the samples, we determined whether Em-cfDNA could be used for AE diagnosis and as a potential indicator of the effectiveness of surgical treatment. We also examined potential associations between Em-cfDNA levels and clinical features of AE patients. RESULTS: Our work demonstrates that varying reads of Em-cfDNA were detectable in the plasma of 100% of preoperative AE patients and that all of the non-AE patients and healthy volunteers were negative. Em-cfDNA has good sensitivity and specificity for the diagnosis of AE. We also found that Em-cfDNA levels apparently have reference value for evaluating the therapeutic efficacy of surgery interventions for AE lesions. Finally, our analysis revealed that Em-cfDNA levels can reflect meaningful information about lesion size in preoperative AE patients. CONCLUSIONS: We demonstrate that sequencing-based monitoring of Em-cfDNA can be used in the clinic as a powerful diagnostic indicator for AE. We also note that there is a strong potential for use of this liquid-biopsy method to monitor ongoing disease status in postintervention AE patients.
Assuntos
Ácidos Nucleicos Livres , Equinococose , Echinococcus multilocularis , Parasitos , Animais , Equinococose/diagnóstico , Echinococcus multilocularis/genética , HumanosRESUMO
We introduced a novel micro/nanofluidic chip platform (MNCP), which is based on an isothermal nucleic acid amplification method. This study aimed to evaluate the MNCP method for influenza A and B viruses detecting and subtyping using throat swab samples from patients with influenza-like illness (ILI). A total of 266 throat swab samples from 266 non-repeated patients with ILI were tested for influenza A and B viruses using three methods, MNCP, a rapid influenza diagnostic test (RIDT), and real-time reverse transcription polymerase chain reaction (rRT-PCR). The results of MNCP were compared to those obtained by rRT-PCR and RIDT and the performance of MNCP was further evaluated. Compared with rRT-PCR results, the rates of sensitivity, specificity, overall concordance, and the kappa value of MNCP were 98.89%, 96.97%, 97.65%, and 0.95 for influenza A virus; 94.95%, 99.38%, 97.68%, and 0.95 for influenza B virus, respectively. Subtypes of influenza A viruses, e.g., A(H1N1)pdm09, A(H3N2), and A(not subtyped), and influenza B viruses could be distinguished in one MNCP assay within 1 h. Compared with rRT-PCR and MNCP, RIDT showed poor clinical sensitivity for influenza virus detection. This study showed MNCP is rapid, sensitive and versatile detecting system with potential for clinical application in pathogen diagnosis for patients with ILI.
RESUMO
An elastin-like polypeptide (ELP) was fused to D-amino acid oxidases (DAAO). ELP-DAAO exhibited a better solubility in aqueous solutions than DAAO, and its enzymatic activity is about 1.6 times that of DAAO. The stability of the proteins was investigated by interacting with urea at various concentrations. The circular dichroism and fluorescence spectra were measured. The results demonstrated that that ELP-DAAO exhibited a much better stability than DAAO, and ELP-DAAO has retained the α-helix content with a high percentage even at a high urea concentration. The results of this work have demonstrated that the ELP tag can be utilized to purify DAAO, in the meantime the solubility and stability of the enzyme are improved.