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BACKGROUND The composition of major and trace elements in arsenopyrite can be used to identify the occurrence of elements and explore the remobilization and migration behaviour of elements in different stages. The Haoyaoerhudong gold deposit in Inner Mongolia is a super large gold deposit hosted in the black shales of the Bayan Obo Group. Gold-bearing minerals such as arsenopyrite and loellingite are present. Previous researchers have used the traditional powder dissolution method to analyze the isotope of the ore and discussed the source of ore-forming materials, but the migration and enrichment mechanism of gold has not been unraveled. OBJECTIVES To understand the gold migration and enrichment process of this deposit. METHODS Based on mineralogy, different types of arsenopyrite were analyzed by electron probe microanalyzer (EPMA) and inductively coupled plasma-mass spectrometry (ICP-MS). The data measured by EPMA was corrected by ZAF program, and the data measured by LA-ICP-MS was quantitatively calculated by "no internal standard-matrix normalized calibration". RESULTS The results showed that loellingite was developed in arsenopyrite. They can be divided into Apy-Ⅰ1, Apy-Ⅰ2, Lo-Ⅰ in progressive shear deformation stage and Apy-Ⅱ1, Apy-Ⅱ2 and Lo-Ⅱ in post shear deformation stage. The major element composition of arsenopyrite in different generations was stable, with a small amount of Co and Ni and a trace amount of Sb, Te, Bi, Pb, Au and Ag. Cobalt was higher in Apy-Ⅱ1 and Apy-Ⅱ2, whereas Au, Bi, Pb and Te were obviously enriched in Apy-Ⅰ1. Loellingite was rich in As (64.06%-67.87%), Co (0.33%-4.98%), Ni (1.23%-6.37%). Trace elements such as Au, Te, Bi, Pb and Ag were more enriched in Lo-Ⅱ. CONCLUSIONS Lo-Ⅱ is the most important gold-bearing mineral. The changes of temperature and sulfur fugacity lead to the precipitation of loellingite and native gold. Native gold is precipitated by remobilization and migration of "invisible gold" in early arsenopyrite and loellingite.

BackgroundClinical trials have demonstrated that immediate initiation of antiretroviral therapy (ART) reduces AIDS-related morbidity and mortality. We tested the hypothesis that initiating ART ≤30 days after human immunodeficiency virus (HIV) diagnosis would be associated with reduced mortality among people living with HIV (PLWH) with CD4 counts >500 cells/μL.MethodsPLWH enrolled in the Chinese National HIV Information System between January 2012 and June 2014 with CD4 counts >500 cells/μL were followed for 12 months. Cox proportional hazards model was used to determine hazard ratios (HRs) for PLWH who initiated ART after HIV diagnosis. ART initiation was treated as a time-dependent variable.ResultsWe enrolled 34581 PLWH with CD4 >500 cells/μL; 1838 (5.3%) initiated ART ≤30 days after diagnosis (immediate ART group), and 19 deaths were observed with a mortality rate of 1.04 per 100 person-years (PY). Fifty-eight deaths were documented among the 5640 PLWH in the delayed ART group with a mortality rate of 2.25 per 100 PY. There were 713 deaths among the 27103 PLWH in the no ART group with a mortality rate of 2.39 per 100 PY. After controlling for potential confounding factors, ART initiation at ≤30 days (adjusted HR, 0.37 [95% confidence interval, .23-.58]) was a statistically significant protective factor.ConclusionsWe found that immediate ART is associated with a 63% reduction in overall mortality among PLWH with CD4 counts >500 cells/μL in China, supporting the recommendation to initiate ART immediately following HIV diagnosis.

Quiescent cancer cells are major impediments to effective radiotherapy (RT) and exhibit limited sensitivity to traditional photon therapy. Herein, the functional role and underlying mechanism of carbon ions in overcoming the radioresistance of quiescent cervical cancer HeLa cells were determined. Briefly, serum withdrawal was used to induce synchronized quiescence in HeLa cells. Quiescent HeLa cells displayed strong radioresistance and DNA repair potential. After irradiation with carbon ions, the DNA damage repair pathway may markedly rely on error‐prone nonhomologous end‐joining in proliferating cells, whereas the high‐precision homologous recombination pathway is more relevant in quiescent cells. This phenomenon could be explained by the ionizing radiation (IR)‐induced cell cycle re‐entry of quiescent cancer cells. There are three strategies for eradicating quiescent cancer cells using high‐linear energy transfer (LET) carbon ions: direct cell death through complex DNA damage; apoptosis via an enhanced mitochondria‐mediated intrinsic pathway; forced re‐entry of quiescent cancer cells into the cell cycle, thereby improving their susceptibility to IR. Silencing β‐catenin signaling is essential for maintaining the dormant state in quiescent cells. Herein, carbon ions activated the β‐catenin pathway in quiescent cells, and inhibition of this pathway improved the resistance of quiescent HeLa cells to carbon ions by alleviating DNA damage, improving DNA damage repair, maintaining quiescent depth, and inhibiting apoptosis. Collectively, carbon ions conquer the radioresistance of quiescent HeLa cells by activating β‐catenin signaling, which provides a theoretical basis for improved therapeutic effects in patients with middle‐advanced‐stage cervical cancer with radioresistance. [ABSTRACT FROM AUTHOR]

Objective To assess if cotrimoxazole prophylaxis administered early during antiretroviral therapy (ART) reduces mortality in Chinese adults who are infected with human immunodeficiency virus (HIV). Methods We did a retrospective observational cohort study using data from the Chinese national free antiretroviral database. Patients older than 14 years who started ART between 1 January 2010 and 31 December 2012 and had baseline CD4+T-lymphocyte (CD4+ cell) count less than 200 cells/µL were followed until death, loss to follow-up or 31 December 2013. Hazard ratios (HRs) for several variables were calculated using multivariate analyses. Findings The analysis involved 23 816 HIV-infected patients, 2706 of whom died during the follow-up. Mortality in patients who did and did not start cotrimoxazole during the first 6 months of ART was 5.3 and 7.0 per 100 person-years, respectively. Cotrimoxazole was associated with a 37% reduction in mortality (hazard ratio, HR: 0.63; 95% confidence interval, CI: 0.56-0.70). Cotrimoxazole in addition to ART reduced mortality significantly over follow-up lasting 6 months (HR: 0.65; 95% CI: 0.59-0.73), 12 months (HR: 0.58; 95% CI: 0.49-0.70), 18 months (HR: 0.49; 95% CI: 0.38-0.63) and 24 months (HR: 0.66; 95% CI: 0.48-0.90). The mortality reduction was evident in patients with baseline CD4+ cell counts less than 50 cells/µL (HR: 0.60; 95% CI: 0.54-0.67), 50-99 cells/µL (HR: 0.66; 95% CI: 0.56-0.78) and 100-199 cells/µL (HR: 0.78; 95% CI: 0.62-0.98). Conclusion Cotrimoxazole prophylaxis started early during ART reduced mortality and should be offered to HIV-infected patients in low- and middle-income countries. [TEXT NOT REPRODUCIBLE IN ASCII] [TEXT NOT REPRODUCIBLE IN ASCII] Objectif Evaluer si la prophylaxie par le cotrimoxazole administree precocement au cours de la therapie antiretrovirale (TAR) reduit la mortalite chez les adultes infectes par le virus de l'immunodeficlence humaine (VIH) en Chine. Methodes Nous avons effectue une etude de cohorte par observation retrospective en utilisant les donnees de la base de donnees antiretrovirale gratuite nationale chinoise. Les patients ages de plus de Mans qui ont commence une TAR entre le 1 erjanvier 2010 et le 31 decembre 2012 et qui avaient un nombre de lymphocytes T CD4+ (cellules CD4+) a la ligne de base inferieur a 200 cellules/µL, ont ete suivis jusqu'a leur decesjusqu'a ce quils soient perdus de vue au suivi ou jusqu'au 31 decembre 2013. Les rapports des risques (RR) pour plusieurs variables sont calcules en utilisant des analyses multivariees. Resultats Le suivi. La mortalite chez les patients qui ont et qui n'ont pas commence a prendre le cotrimoxazole au cours des 6 premiers mois de la TAR etait de 5,3 et 7,0 pour 100 personnes-annees, respectivement. Le cotrimoxazole etait associe avec 37% de reduction de la mortalite (rapport des risques, RR: 0,63; intervalle de confiance a 95%, IC 95%: 0,56-0,70). Le cotrimoxazole ajoute a la TAR a reduit significativement la mortalite au cours du suivi des 6 derniers mois (RR: 0,65; IC 95%: 0,59-0,73), des 12 derniers mois (RR: 0,58; IC 95%: 0,49-0,70), des 18 derniers mois (RR: 0,49; IC 95%: 0,38-0,63) et des 24 derniers mois (RR: 0,66; IC 95%: 0,48-0,90). La reduction de la mortalite etait evidente chez les patients avec un nombre de cellules CD4+ a la ligne de base inferieur a 50 cellules/µL (RR: 0,60; IC 95%: 0,54-0,67), 50-99 cellules/µL (RR: 0,66; IC 95%: 0,56-0,78) et 100-199 cellules/µL (RR: 0,78; IC 95%: 0,62-0,98). Conclusion La prophylaxie par le cotrimoxazole commencee precocement au cours de la TAR a reduit la mortalite et devrait etre proposee aux patients infectes par le VIH dans les pays a revenu faible et a revenu intermediaire. [TEXT NOT REPRODUCIBLE IN ASCII] Objetivo Evaluarsi la profilaxis con cotrimoxazol en una etapa temprana de la terapia antirretroviral (TAR) reduce la mortalidad en adultos de origen chino infectados por el virus de la inmunodefidencia humana (VIH). Metodos Se llevo a cabo un estudio de cohorte observacional retrospectivo utilizando los datos de la base de datos nacional de China de antirretrovirales de uso gratuito. Por otro lado, se realizo un seguimiento a pacientes mayores de 14anos que iniciaron el tratamiento con TAR entre el 1 de enero de 2010 y el 31 de diciembre de 2012 y con recuento basal de linfocitosTCD4+ (celula CD4+) inferior a 200 celulas/ pl hasta su muerte, la perdida de seguimiento o el 31 de diciembre de 2013. Se calcularon los cocientes de riesgos (CR) para diversas variables mediante analisis multivariados. Resultados En el analisis participaron 23 816 pacientes infectados por el VIH, 2706 de los cuales fallecieron durante el seguimiento. La mortalidad entre los pacientes que iniciaron y no Iniciaron el tratamiento con cotrimoxazol durante los primeros 6 meses de la TAR fue de 5,3 y 7,0 por 100 personas/anos, respectivamente. Cotrimoxazol se asocio a una reduccion del 37 % en la mortalidad (cociente de riesgos, CR: 0,63, intervalo de confianza del 95 %, 1C: 0,56 - 0,70). Ademas de la TAR, cotrimoxazol redujo la mortalidad considerablemente durante el seguimiento de 6 meses (CR: 0,65; 1C del 95 %: 0,59 - 0,73), 12 meses (CR: 0,58; IC del 95 %: 0,49 - 0,70), 18 meses (CR: 0,49; 1C del 95 %: 0,38 - 0,63) y 24 meses (CR: 0,66; IC del 95 %: 0,48 - 0,90). La reduccion de la mortalidad resulto evidente en pacientes con recuento basal de celulas CD4+ Inferior a 50 celulas/µl (CR: 0,60; IC del 95 %: 0,54 - 0,67), 50 - 99 celulas/µl (CR: 0,66; IC del 95 %: 0,56 - 0,78) y 100 -199 celulas/µl (CR: 0,78; IC del 95%: 0,62-0,98). Conclusion La profilaxis con cotrimoxazol inidada en una etapa temprana de laTAR redujo la mortalidad y debe ofrecerse a los pacientes infectados por el VIH en paises de Ingresos bajos y medios., Introduction With the rapid rise in the availability of antiretroviral therapy (ART), the number of people dying from acquired immune deficiency syndrome (AIDS) has dramatically declined. However, in many low- [...]