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The resource connection between microflora and microfauna in soil micro-food web is of great importance for soil ecosystem in terms of maintaining its quality, productivity, and sustainability. However, the responses of soil micro-food web to continuous cropping (CC) are still unclear at present. In this study, the responses of soil micro-food web to different duration of CC (0 (the control), 5, 10, 15, and 20 years) were investigated in a long-term experiment in Xinjiang, China. The trophic groups of soil nematodes in 0–10 cm and 11–20 cm soil layers were determined according to the trophic habits, oesophageal structure, and predation pattern. The stability and maturity of soil micro-food web were determined by nematode faunal analysis. The connectance was determined according to the predation relationship between nematodes and microbes. The results showed that the abundance of nematodes in the 10- and 20-year CC treatments were higher than that in the control in the 0–10 cm soil layer, and the abundance of nematodes in the 5- and 20-year CC treatments were also higher than that in the control in the 11–20 cm soil layer. In the same soil layer, the abundance of plant parasites in the 10- and 20-year CC treatments and omnivores-predators in the 5- and 20-year CC treatments were higher than those in the control. CC increased the metabolic footprint of omnivore-predators and structure footprint in both soil layers. The soil micro-food web in the CC treatments received fewer disturbances than that in the control, which increased soil nutrients. Meanwhile, the soil micro-food web became stable and mature. The connectance of omnivore-predators channel in the 5-year CC treatment was higher than that in the control in the 0–10 cm soil layer, and the connectance of bacterial channel in the 20-year CC treatment and omnivores-predators channel in the 5-, 10-, and 15-year CC treatments were also higher than those in the control in the 11–20 cm soil layer. Mantel test showed that soil pH, electrical conductivity, organic carbon, total nitrogen, and C/N ratio were key factors affecting soil nematode communities. Therefore, continuous cropping could effectively enhance the soil micro-food web structure and function through bottom-up effects in the cotton fields. • Continuous cropping increased the abundance and metabolic activities of soil nematodes. • Different continuous cropping years were more favorable for carbon allocating into soil nematodes than that in the control. • Continuous cropping affected nematode communities by improving soil food web conditions. • Carbon flows in bacterial and omnivores-predators channels were increased under continuous cropping. [ABSTRACT FROM AUTHOR]

Background and Objective: Of three first-line anti-tuberculosis (anti-TB) drugs, isoniazid is most commonly associated with hepatotoxicity. Differences in INH-induced toxicity have been attributed to genetic variability at several loci, NAT2, CYP2E1, GSTM1and GSTT1, that code for drug-metabolizing enzymes. This study evaluated whether the polymorphisms in these enzymes were associated with an increased risk of anti-TB drug-induced hepatitis in patients and could potentially be used to identify patients at risk of liver injury. Methods and Design: In a cross-sectional study, 2244 tuberculosis patients were assessed two months after the start of treatment. Anti-TB drug-induced liver injury (ATLI) was defined as an ALT, AST or bilirubin value more than twice the upper limit of normal. NAT2, CYP2E1, GSTM1 and GSTT1 genotypes were determined using the PCR/ligase detection reaction assays. Results: 2244 patients were evaluated, there were 89 cases of ATLI, a prevalence of 4% 9 patients (0.4%) had ALT levels more than 5 times the upper limit of normal. The prevalence of ATLI was greater among men than women, and there was a weak association with NAT2*5 genotypes, with ATLI more common among patients with the NAT2*5*CT genotype. The sensitivity of the CT genotype for identifying patients with ATLI was 42% and the positive predictive value 5.9%. CT ATLI was more common among slow acetylators (prevalence ratio 2.0 (95% CI 0.95,4.20) )compared to rapid acetylators. There was no evidence that ATLI was associated with CYP2E1 RsaIc1/c1genotype, CYP2E1 RsaIc1/c2 or c2/c2 genotypes, or GSTM1/GSTT1 null genotypes. Conclusions: In Xinjiang Uyghur TB patients, liver injury was associated with the genetic variant NAT2*5, however the genetic markers studied are unlikely to be useful for screening patients due to the low sensitivity and low positive predictive values for identifying persons at risk of liver injury. [ABSTRACT FROM AUTHOR]