Identification potential biomarkers in pulmonary tuberculosis and latent infection based on bioinformatics analysis.

BACKGROUND: The study aimed to identify the potential biomarkers in pulmonary tuberculosis (TB) and TB latent infection based on bioinformatics analysis. METHODS: The microarray data of GSE57736 were downloaded from Gene Expression Omnibus database. A total of 7 pulmonary TB and 8 latent infection samples were used to identify the differentially expressed genes (DEGs). The protein-protein interaction (PPI) network was constructed by Cytoscape software. Then network-based neighborhood scoring analysis was performed to identify the important genes. Furthermore, the functional enrichment analysis, correlation analysis and logistic regression analysis for the identified important genes were performed. RESULTS: A total of 1084 DEGs were identified, including 565 down- and 519 up-regulated genes. The PPI network was constructed with 446 nodes and 768 edges. Down-regulated genes RIC8 guanine nucleotide exchange factor A (RIC8A), basic leucine zipper transcription factor, ATF-like (BATF) and microtubule associated monooxygenase, calponin LIM domain containing 1 (MICAL1) and up-regulated genes ATPase, Na+/K+ transporting, alpha 4 polypeptide (ATP1A4), histone cluster 1, H3c (HIST1H3C), histone cluster 2, H3d (HIST2H3D), histone cluster 1, H3e (HIST1H3E) and tyrosine kinase 2 (TYK2) were selected as important genes in network-based neighborhood scoring analysis. The functional enrichment analysis results showed that these important DEGs were mainly enriched in regulation of osteoblast differentiation and nucleoside triphosphate biosynthetic process. The gene pairs RIC8A-ATP1A4, HIST1H3C-HIST2H3D, HIST1H3E-BATF and MICAL1-TYK2 were identified with high positive correlations. Besides, these genes were selected as significant feature genes in logistic regression analysis. CONCLUSIONS: The genes such as RIC8A, ATP1A4, HIST1H3C, HIST2H3D, HIST1H3E, BATF, MICAL1 and TYK2 may be potential biomarkers in pulmonary TB or TB latent infection.

[Pulmonary infection with Mycobacterium massiliense: a case report and review of the literature].

OBJECTIVE: To analyze the clinical features and differential diagnosis of pulmonary infection with Mycobacterium massiliense (M. massiliense). METHODS: The clinical manifestations and laboratory test results of our patient were analyzed and the strain isolated from the patient was tested by bacteriological and molecular methods. The partial gene fragments of rpoB and hsp65 were amplified by PCR, sequenced and compared with GeneBank database in NCBI for identification of Mycobacterium species. RESULTS: The patient was a 72 year old female, who had been admitted to hospital several times because of recurrent respiratory symptoms which had failed to improve upon treatment. This time, pulmonary infection with M. massiliense was confirmed by clinical manifestation and laboratory results. M. massilence isolated from the sputum of our patient was confirmed by bacteriological and molecular methods. The results of specific segments of rpoB and hsp65 tested by PCR and sequence analysis, and compared with that of mycobacterium in NCBI, showed that the DNA homology was 100% and 99% respectively. The results of drug sensitivity test showed that this strain was resistant to multiple drugs. According to the results of drug susceptibility tests and the condition of the patient, therapy with cefoxitin sodium and amikacin was used and the drugs were effective. CONCLUSIONS: The clinical manifestations and the chest imaging of pulmonary infection with M. massiliens were similar to those of Mycobacterium tuberculosis, which can be differentiated by laboratory tests.

Protective effects of hemin in an experimental model of ventilator-induced lung injury.

Mechanical ventilation is an indispensable life-support modality for critically ill patients with acute lung injury or acute respiratory distress syndrome. Unfortunately, mechanical ventilation even the protective ventilation strategies may evoke ventilator-induced lung injury. Heme oxygenase-1 (HO-1) has recently exhibited anti-inflammatory and anti-oxidative properties in vitro and in vivo. The effect of HO-1 in ventilator-induced lung injury has not been fully characterized. In this study, rabbits were subjected to high tidal volume ventilation to induce ventilator-induced lung injury, which was confirmed by histopathological alterations, increased bronchoalveolar lavage fluid protein content and lung wet-to-dry ratio. In contrast to the level of HO-1 expression in high tidal volume group, pretreatment with hemin, an inducer of HO-1, further up-regulated HO-1 expression. At the same time, these lung injury indexes were attenuated markedly. This pulmonary protection was accompanied by a decrease in bronchoalveolar lavage fluid neutrophil count and in lung myeloperoxidase activity. Besides, pretreatment with hemin prohibited the production of proinflammatory cytokines, including tumor necrosis factor (TNF)-α, interleukin (IL)-8, and up-regulated the level of anti-inflammatory cytokine interleukin (IL)-10 in bronchoalveolar lavage fluid. Furthermore, a decreased malondialdehyde activity, a marker of oxidative stress and a robust increase in total antioxidant capacity were observed in hemin-treated animals. Our findings suggest that HO-1 up-regulation by hemin plays a protective role in ventilator-induced lung injury by suppression inflammatory process and oxidative stress.