RESUMO
Background: MicroRNAs (miRNAs) play a vital role in tuberculosis (TB). Vitamin D receptor (VDR), an miRNA target gene, and its ligand, vitamin D3 (VitD3), have been reported to exert protective effects against TB. However, whether miRNAs can affect the progression of TB by targeting VDR has not been reported. Materials and methods: Research subjects were selected according to defined inclusion criteria. A clinical database of 360 samples was established, including the subjects' demographic information, miRNA expression profiles and cellular experimental results. Two candidate miRNAs, miR-27a-3p, and miR-30b-5p, were identified by a high-throughput sequencing screen and validated by qRT-PCR assays. Univariate and multivariate statistical analyses were performed. VDR and NF-kB p65 protein levels were detected by Western blot assays. Proinflammatory cytokine expression levels were detected by enzyme-linked immunosorbent assay (ELISA). Luciferase assays and fluorescence-activated cell sorting (FACS) were further applied to elucidate the detailed mechanisms. Results: Differential miRNA expression profiles were obtained, and miR-27a-3p and miR-30b-5p were highly expressed in patients with TB. These results showed that the two miRNAs were able to induce M1 macrophage differentiation and inhibit M2 macrophage differentiation. Further experiments showed that the two miRNAs decreased the VDR protein level and increased proinflammatory cytokine secretion by macrophages. Mechanistically, the miRNAs targeted the 3' untranslated region (3'UTR) of the VDR mRNA and thereby downregulated VDR protein levels by post-transcriptional regulation. Then, due to the reduction in VDR protein levels, the NF-kB inflammatory cytokine signaling pathway was activated, thus promoting the progression of TB. Conclusion: Our study not only identified differentially expressed miRNAs between the TB and control groups but also revealed that miR-27a-3p and miR-30b-5p regulate proinflammatory cytokine secretion and macrophage differentiation through VDR in macrophages. Thus, these two miRNAs influence the progression of TB.
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Background: Coronavirus disease 2019 (COVID-19) is spreading throughout the world. Limited data are available for recurrence of positive severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) results in patients with long duration of COVID-19. Methods: We reported four cases recovered from COVID-19 with recurrence of positive SARS-CoV-2 results during the long-term follow-up. Results: The four patients recovered from COVID-19 showed recurrence of positive SARS-CoV-2 results for more than 120 days with no symptoms and normal chest CT scan. Conclusions: The dynamic surveillance of SARS-CoV-2 by nucleic acid detection and serological assays is important for asymptomatic patients who might be potentially infectious.
RESUMO
OBJECTIVE: To explore the value of BACs-on-BeadsTM (BoBs) for the practice of prenatal diagnosis. METHODS: The results of chromosomal karyotyping and BoBs of 1773 prenatal samples were compared. Microdeletions and microduplications detected by BoBs were subjected to chromosome microarray analysis (CMA) with informed consent from patients. RESULTS: BoBs has detected 46 cases of common aneuploidies involving chromosomes 13, 18, and 21, and 16 cases involving X and Y chromosomes. For 4 fetuses with normal results by BoBs, karyotyping analysis of amniotic fluid sample suggested low percentage mosaicisms (< 20%). BoBs has detected none of the 9 common microdeletions, but 14 male fetuses with Xp22 microdeletions and 5 with other microdeletions/microduplications. In 10 cases, the couples had chosen CMA verification, and the results were all consistent. CONCLUSION: As a rapid diagnostic technique, BoBs has a high accuracy for common aneuploidies, and is capable of discovering certain chromosome microdeletions and microduplications. The difficulty lies in the inability to detect low proportion mosaicisms and the consultation following detection for male fetuses carrying Xp22 microdeletions.
