Prevalence of nontuberculous mycobacteria and the emergence of rare species in Henan Province, China.

Nontuberculous mycobacteria (NTM) is a large group of mycobacteria other than the Mycobacterium tuberculosis complex and Mycobacterium leprae. Epidemiological investigations have found that the incidence of NTM infections is increasing in China, and it is naturally resistant to many antibiotics. Therefore, studies of NTM species in clinical isolates are useful for understanding the epidemiology of NTM infections. The present study aimed to investigate the incidence of NTM infections and types of NTM species. Of the 420 samples collected, 285 were positive for M. tuberculosis, 62 samples were negative, and the remaining 73 samples contained NTM, including 35 (8.3%) only NTM and 38 (9%) mixed (M. tuberculosis and NTM). The most prevalent NTM species were Mycobacterium intracellulare (30.1%), followed by Mycobacterium abscessus (15%) and M. triviale (12%). M. gordonae infection was detected in 9.5% of total NTM-positive cases. Moreover, this study reports the presence of Mycobacterium nonchromogenicum infection and a high prevalence of M. triviale for the first time in Henan. M. intracellulare is the most prevalent, accompanied by some emerging NTM species, including M. nonchromogenicum and a high prevalence of M. triviale in Henan Province. Monitoring NTM transmission and epidemiology could enhance mycobacteriosis management in future.

Novel automated AIMLAM for diagnosis of Mycobacterium tuberculosis.

Aim: A rapid and precise diagnostic method is crucial for timely intervention and management of tuberculosis. The present study compared the diagnostic accuracy of a novel lipoarabinomannan (LAM) antigen test, AIMLAM, for tuberculosis in urine samples. Methodology: The study subjected 106 TB suspects to smear microscopy, MGIT, GeneXpert and AIMLAM. Results: Among 106, smear microscopy identified 36 as positive (33%) (sensitivity; 70.93%, 95% CI (60.14-80.22%), while MGIT showed 38 positive (36.8%). GeneXpert detected 59 positives (sensitivity; 96.83, 95% CI (89.00-99.61%)). AIMLAM declared 61 as positive (57.5%) (sensitivity; 100.00, 95% CI (94.13-100.00%) and 45 as negative (42.5%). Conclusion: Overall, AIMLAM demonstrated better diagnostic accuracy than GeneXpert Assay, smear microscopy and MGIT liquid culture in urine samples.

This study describes a new way to detect tuberculosis, called AIMLAM. Unlike traditional methods that use sputum or blood, AIMLAM tests urine samples and bodily fluids. It is automated and uses easily accessible samples to identify a tuberculosis infection, so may be a convenient and noninvasive option for healthcare providers. The test shows promising results in terms of accuracy and sensitivity.

Effects of caspase activity of yak meat and internal environment changing during aging.

The objective of this study was to investigate the protease family caspases in skeletal muscle and their potential contribution to postmortem proteolysis and meat tenderization. Nine yaks were slaughtered, and samples of Longissimus dorsal were injected with AC-DEVD-CHO at a ratio of 1:1 (w/v) and then stored at 4 °C for 2, 6, 12, 24, 72, and 120 h. Results indicate that the morphological changes of the muscle fibers are significantly obstructed, which is not conducive to the subsequent degradation of proteins. After inhibiting the activity of Caspase- 3, the activity of Caspase-8 and 9 and the energy metabolism was affected. In the case of without inhibition of caspase, the pH value decreased and then increased. The meat color and the water retention are better, the muscle fiber skeleton protein degradation is remarkable, the tenderness is improved. Furthermore, yak meat tenderness was improved by apoptotic pathway during aging.