Smear-negative pulmonary TB (PTB) is difficult to diagnose. Current diagnosis and treatment monitoring methods have inherent limitations. Droplet digital PCR (ddPCR) is a new technique with high sensitivity. This study presents a novel ddPCR for rapid and sensitive identification of Mycobacterium tuberculosis (MTB). MTB DNA was detected in respiratory specimens from suspected PTB cases using ddPCR assay, which was directed at two different locations within IS6110. We, for the first time, evaluated the clinical diagnostic ability of this ddPCR for paucibacillary smear-negative PTB. A total of 605 PTB suspects were recruited, including 263 patients with confirmed PTB (84.03% from smear-negative PTB) and 342 without PTB. The sensitivity and specificity of IS6110 ddPCR were 61.22% (95% confidence interval (CI) 55.00-67.10%) and 95.03% (95% CI 92.20-97.10%) for total PTB and 57.92% (95% CI 51.10-64.50%) and 94.57% (95% CI 91.20-96.90%) for smear-negative PTB. ddPCR assay outperformed Xpert MTB/RIF (53.08% vs 28.46%, P = 0.020) in smear-negative PTB detection. Furthermore, effective anti-TB treatment was linked to significantly lower IS6110 copies detected by ddPCR. Herein, we developed and validated a highly sensitive and robust ddPCR assay for MTB quantification in respiratory specimens, which improves diagnosis and therapeutic effect evaluation of smear-negative PTB.

Background. The accumulation of the hepatotoxic substance protoporphyrin IX (PPIX) induced by aminolevulinate synthase 1 (ALAS1) activation is one of the important mechanisms of antituberculosis drug-induced hepatotoxicity (ATDH). Forkhead box protein O1 (FOXO1) may activate ALAS1 transcription. However, little is known about their roles in ATDH; we performed a study to determine the association between polymorphisms in the two genes and ATDH susceptibility. Then, we verified this possible association by cellular functional experiments. Materials and Methods. Tag single-nucleotide polymorphisms (TagSNPs) in the two genes were genotyped in 746 tuberculosis patients. The frequencies of the alleles, genotypes, genetic models, and haplotype distribution of the variants were compared between the case and control groups. L-02 cells and HepG2 cells were incubated with the indicated concentration of isoniazid (INH) and rifampicin (RIF) for the desired times, and then the expression levels of ALAS1 and FOXO1 mRNAs and proteins were detected. HepG2 cells were transiently transfected with FOXO1 siRNA to observe the effect of changes in the FOXO1 expression on the cell survival rate and ALAS1 expression. Results. The C allele at rs2755237 and the T allele at rs4435111 in the FOXO1 gene were associated with a decreased risk of ATDH. The expression of ALAS1 in both L-02 cells and HepG2 cells was increased by the coadministration of INH/RIF (600/200μM) for 24h. Although FOXO1 expression was reduced slightly by the same treatment, its content in the nucleus was significantly increased. However, the cell survival rate and ALAS1 expression level were not significantly altered by the downregulation of FOXO1 in HepG2 cells. Conclusions. Variants of the rs4435111 and rs2755237 loci in the FOXO1 gene were associated with susceptibility to ATDH. Coadministration of INH/RIF promoted the transfer of FOXO1 from the cytoplasm to the nucleus, but the functional significance of its nuclear translocation requires further verification.

Python programming is widely used in scientific computing, data processing, visualization, image processing, natural language processing, machine learning, artificial intelligence and other fields, and more and more majors offer this course to provide strong support for cultivating high-quality composite "new engineering" talents. This paper explores the teaching of Python programming course for biomedical engineering majors in view of the shortcomings of the current teaching of Python programming, from several aspects such as the objectives and ideas of hybrid teaching, the content and structure of hybrid teaching in PBL mode, the design of online and offline teaching steps and teaching activities, and the design of course assessment system. The aim is to enhance students' self-learning ability and motivate them to learn, so as to cultivate their comprehensive and innovative practical application ability.