Role of Diabetes Mellitus on Treatment Effects in Drug-susceptible Initial Pulmonary Tuberculosis Patients in China.

We assessed the role of diabetes mellitus (DM) on treatment effects in drug-susceptible initial pulmonary tuberculosis (PTB) patients. A prospective study was conducted in eight provinces of China from October 2008 to December 2010. We enrolled 1,313 confirmed drug-susceptible initial PTB patients, and all subjects received the treatment regimen (2H3R3E3Z3/4H3R3) as recommended by the national guidelines. Of the 1,313 PTB patients, 157 (11.9%) had DM; these patients had more sputum smear-positive rates at the end of the second month [adjusted odds ratios (aOR) 2.829, 95% confidence intervals (CI) 1.783-4.490], and higher treatment failure (aOR 2.120, 95% CI 1.565-3.477) and death rates (aOR 1.536, 95% CI 1.011-2.628). DM was a contributing factor for culture-positive rates at the end of the second month and treatment failure and death of PTB patients, thus playing an unfavorable role in treatment effects of PTB.

Risk of Treatment Failure in Patients with Drug-susceptible Pulmonary Tuberculosis in China.

The objective of this prospective study of the risks of treatment failure in patients with drug-susceptible pulmonary tuberculosis (PTB) was to provide reference data to help develop a disease control strategy. Participants were recruited in eight provinces of China from October 2008 to December 2010. A total of 1447 patients with drug-susceptible PTB and older than 15 years of age were enrolled. Demographic characteristics, bacteriological test results, and patient outcome, i.e., cure or treatment failure were recorded and compared using the chi-square or Fisher's exact tests. Multivariate logistic regression was used to identify factors associated with risk of treatment failure. Of the 1447 patients who were enrolled, 1349 patients (93.2%) were successfully treated and 98 (6.8%) failed treatment. Failure was significantly associated with age 365 years [odds ratio (OR)=2.522, 95% confidence interval (CI): (1.097-5.801)], retreatment [OR=2.365, 95% CI: (1.276-4.381)], missed medicine [OR=1.836, 95% CI: (1.020-3.306)], treatment not observed [OR=1.879 95% CI: (1.105-3.195)], and positive culture result after the first [OR=1.971, 95% CI: (1.080-3.597)] and second month [OR=4.659, 95% CI: (2.590-8.382)]. The risk factors associated with treatment failure were age 365 years, retreatment, missed medication, treatment not observed, and positive culture at the end of month 1 or month 2. These risk factors should be monitored during treatment and interventions carried out to reduce or prevent treatment failure and optimize treatment success.

[Stable Isotope Characteristics and Vapor Source of Precipitation in the South and North Slopes of Wushaoling Mountain].

We analyze the stable isotope characteristics and vapor source of precipitation in a monsoon marginal area in the southern and northern slopes of Wushaoling Mountain, northwestern China, using 97 precipitation samples collected from October 2016 to October 2017. Correlation analysis and HYSPLIT model are used to study the characteristics of stable isotopes in precipitation, local meteoric water line equation, temperature and precipitation effects, and vapor source. The study found the following results. ① The slope and intercept of the southern slope local meteoric water line were lower than of those of the northern slope and global averages. ② Although the isotope temperature effects and seasonal effects of both slopes were obvious, the temperature effect of the northern slope was more obvious than of that of the southern slope. ③ The stable isotopes of precipitation during the summer on the northern slope and the precipitation on the southern slope<5 mm revealed that the precipitation effect was weak. There was no obvious precipitation effect in other seasons or in other precipitation levels on both slopes. ④ Vapor from the northwest and north accounted for>90% of the total. The northern slope was rarely affected by monsoon vapor, but the southern slope was affected by the southeast monsoon during the summer. Local water vapor recycling contributed to water vapor in the southern and northern slopes of Wushaoling Mountain. This study could improve the cognition of precipitation isotopic evolution in alpine regions, and lays a foundation for further research on isotope hydrology in cold and arid regions.

Structural analysis of the regulatory mechanism of MarR protein Rv2887 in M. tuberculosis.

MarR family proteins are transcriptional regulators that control expression of bacterial proteins involved in metabolism, virulence, stress responses and multi-drug resistance, mainly via ligand-mediated attenuation of DNA binding. Greater understanding of their underlying regulatory mechanism may open up new avenues for the effective treatment of bacterial infections. To gain molecular insight into the mechanism of Rv2887, a MarR family protein in M. tuberculosis, we first showed that it binds salicylate (SA) and para-aminosalicylic acid (PAS), its structural analogue and an antitubercular drug, in a 1:1 stoichiometry with high affinity. Subsequent determination and analysis of Rv2887 crystal structures in apo form, and in complex with SA, PAS and DNA showed that SA and PAS bind to Rv2887 at similar sites, and that Rv2887 interacts with DNA mainly by insertion of helix α4 into the major groove. Ligand binding triggers rotation of the wHTH domain of Rv2887 toward the dimerization domain, causing changes in protein conformation such that it can no longer bind to a 27 bp recognition sequence in the upstream region of gene Rv0560c. The structures provided here lay a foundation for the design of small molecules that target Rv2887, a potential new approach for the development of anti-mycobacterials.

[Chemical composition and daily variation of melt water during ablation season in monsoonal temperate Glacier region: a case study of Baishui Glacier No. 1].

Melt water samples collected continuously from 29 August to 3 September 2009 in the Baishui Glacier No. 1 at elevation of 4750 m were analyzed for pH, conductivity, delta18O and inorganic ions. The results showed that the pH had obvious diurnal variations and was increased slightly by the influence of precipitation. The dissolution of alkaline soluble salts in the dust was the main reason for the increase of melt water conductivity; the value of delta18O was relatively low in strong ablation period and high in slight ablation period. Different from other research areas, the concentrations of Na+, K+, which were influenced by lithological and marine water vapor, were higher than that of Mg2+ in the study area; HCO3- and Ca2+ accounted for more than 80% of total ions in snow and ice melt water, indicating that the ions mainly came from limestone and the melt water was a typical carbonate solution; The content of melt water had an obvious daily change with temperature change, but the response amplitudes were different; Monsoon transport, local rock lithology, human industrial and agricultural activities were the main sources of inorganic ions and the deciding factors of the ion composition in the Baishui Glacier No. 1.

[Geochemistry of surface and ground water in the Lijang basin, Northwest Yunnan].

The study focused on the chemical element compositions of river water and groundwater in Lijiang Basin. Water samples were collected in Baishui, Sanshu, Geji and Shuhe rivers in Lijiang Basin to analyze pH, conductivity and ion concentration, in order to understand the contributions of anthropogenic activities and rock weathering to river solutes. The results show that all water samples are mildly alkaline and are rich in Ca2+ and HCO3-, which account for 54.8 and 92.4 percentage of total ion concentration respectively. Obvious variations have been perceived during monsoon and westward wind season. The ion concentration of river water is lower than that of groundwater. With decreasing elevation, the ion concentrations are found to increase considerably in the study region. According to source study of major ions, water chemistry is mainly influenced by precipitation rock weathering and dissolving processes. In addition, precipitation is an important factor in monsoon seasons whereas the anthropogenic inputs have lead to light pollution on water in residential district.

[Characteristics of constant inorganic ions in precipitation at different altitudes precipitation in Yulong Snow Mountain area].

According to the different altitudes precipitation samples in Yulong Snow Mountain area in Yunnan Province from July 26 2005 to July 31 2005, the precipitation chemical characteristics of different altitudes were analyzed with the sea salt iron tracer analysis method. Sea salt tracer analysis showed that Cl-, Na+ had high proportion marine source, amounting 74.79% and 73.53% respectively while the other ions mainly were nonmarine sources. The average percentage of nonmarine sources of NO3-, SO4(2-), K+, Mg2+, Ca2+ were 100%, 93.54%, 97.29%, 81.77%, 99.66%. Statistics chart showed the changes of cation outweigh the anion greatly. The cation concentration ranged between 0.51-5.26 mg/L and anion concentration ranged between 0.99-4.90 mg/L, inferring the cation have more complicated sources. Further analysis showed terrestrial ions, especially near source terrestrial ion composition greatly impact the precipitation ion concentration. Human activities lead to higher anion concentration at alt. 2950-4800 m and precipitation ion concentration was correlated significantly with local atmospheric circulation. The most rock are limestone caused high precipitation cations in Yulong Snow Mountain, such as Ca2+ and Mg2+.

[Character and sources of conventional anion in different water bodies on the summer in Yulong Snow Mountain area].

Different water samples were collected at Mt. Yulong Region located in lijiang city, Yunnan Province from July 22 to July 28 in 2005. The concentration of anion was measured by Dionex-3000 Ion chromatography and Dionex-600 ion chromatography, different water bodies anion composition and concentration in the study area were analyzed by applying approaches of cluster analysis sea salt iron tracer and typical backward trajectories analyze. The results show that the anion concentration of water of altitude higher than 3 180 m takes on natural state and the influence of human activities and foundation rock is less significant. However, human activities and foundation rock exert direct and decisive influence on the anion concentration of water of altitude lower than 3 180 m, with more significant effects than high altitude. Cluster analysis shows that at high altitude anion concentration and composition of water have strong consistency, the consistency of different water bodies in low altitude area anions is weak, indicating the influence factors is more complex in low altitude than high altitude. Sea salt tracer analysis indicates that the average proportion of nonmarine source of Cl- is 65%; NO3- is predominantly of continental origin; nonmarine sources proportion of SO4(2-) is 93.7%. Typical backward trajectories analyze found that the mostly vapor in the region mainly from the Indian Ocean, part of the vapors from the eastern Pacific, the west wind South Branch occasionally along Tibetan Plateau into the study area. SO4(2-) and NO3(-) which from mainly from Southeast Asia and South Asia input with the monsoon circulation.