The enantioconvergent radical C(sp3)–C(sp2) cross-coupling of alkyl halides with alkenylboronate esters is an appealing tool in the assembly of synthetically valuable enantioenriched alkenes owing ...to the ready availability, low toxicity, and air/moisture stability of alkenylboronate esters. Here, we report a copper/chiral N,N,N-ligand catalytic system for the enantioconvergent cross-coupling of benzyl/propargyl halides with alkenylboronate esters (>80 examples) with good functional group tolerance. The key to the success is the rational design of hemilabile N,N,N-ligands by mounting steric hindrance at the ortho position of one coordinating quinoline ring. Thus, the newly designed ligand could not only promote the radical cross-coupling process in the tridentate form but also deliver enantiocontrol over highly reactive alkyl radicals in the bidentate form. Facile follow-up transformations highlight its potential utility in the synthesis of various enantioenriched building blocks as well as in the late-stage functionalization for drug discovery.
AIM To establish a simplified, reproducible D-galactosamineinduced cynomolgus monkey model of acute liver failure having an appropriate treatment window. METHODS Sixteen cynomolgus monkeys were ...randomly dividedinto four groups(A, B, C and D) after intracranial pressure(ICP) sensor implantation. D-galactosamine at 0.3, 0.25, 0.20 + 0.05(24 h interval), and 0.20 g/kg body weight, respectively, was injected via the small saphenous vein. Vital signs, ICP, biochemical indices, and inflammatory factors were recorded at 0, 12, 24, 36, 48, 72, 96, and 120 h after D-galactosamine administration. Progression of clinical manifestations, survival times, and results of H&E staining, TUNEL, and Masson staining were recorded. RESULTS Cynomolgus monkeys developed different degrees of debilitation, loss of appetite, and jaundice after D-galactosamine administration. Survival times of groups A, B, and C were 56 ± 8.7 h, 95 ± 5.5 h, and 99 ± 2.2 h, respectively, and in group D all monkeys survived the 144-h observation period except for one, which died at 136 h. Blood levels of ALT, AST, CK, LDH, TBi L, Cr, BUN, and ammonia, prothrombin time, ICP, endotoxin, and inflammatory markers (tumor necrosis factor(TNF)-α, interleukin(IL)-1β, and IL-6) significantly increased compared with baseline values in different groups(P < 0.05). Pathological results showed obvious liver cell necrosis that was positively correlated with the dose of D-galactosamine.CONCLUSION We successfully established a simplified, reproducible D-galactosamine-induced cynomolgus monkey model of acute liver failure, and the single or divided dosage of 0.25 g/kg is optimal for creating this model.
Interleukin-6 has been shown to be involved in nerve injury and nerve regeneration, but the effects of long-term administration of high concentrations of interleukin-6 on neurons in the central ...nervous system is poorly understood. This study investigated the effects of 24 hour expo-sure of interleukin-6 on cortical neurons at various concentrations （0.1, 1, 5 and 10 ng/mL） and the effects of 10 ng/mL interleukin-6 exposure to cortical neurons for various durations （2, 4, 8, 24 and 48 hours） by studying voltage-gated Na＋ channels using a patch-clamp technique. Volt-age-clamp recording results demonstrated that interleukin-6 suppressed Na＋ currents through its receptor in a time- and dose-dependent manner, but did not alter voltage-dependent activation and inactivation. Current-clamp recording results were consistent with voltage-clamp recording results. Interleukin-6 reduced the action potential amplitude of cortical neurons, but did not change the action potential threshold. The regulation of voltage-gated Na＋channels in rat corti-cal neurons by interleukin-6 is time- and dose-dependent.
Myostatin, a member of the transforming growth factor beta（TGF-β） superfamily, is a dominant inhibitor that acts to limit skeletal muscle growth and development. In this study, we generated ...transgenic mice that express porcine myostatin containg mutations at its cleavage site（RSRR） to evaluate its effect on muscle mass. Results showed that the weight of four skeletal muscles including gastrocnemius, rectus femoris, tibialis anterior, and pectoralis increased by 17.83 and 28.39%, 21.76 and 28.70%, 34.31 and 41.62%, 53.21 and 27.54% in transgenic male and female mice, respectively, compared to their corresponding non-transgenic control mice. Measurement of muscle fiber size and number indicated that the mean myofiber size increased by 50.73 and 61.30% in transgenic male and female mice respectively compared to the non-transgenic controls. However, there was no difference in the number of myofiber between transgenic and non-transgenic male mice. These results clearly demonstrated that the increase in skeletal muscle mass in transgenic mice is caused by hypertrophy instead of hyperplasia.
Human respiratory syncytial virus(RSV) is an important pediatric pathogen of lower respiratory tract worldwide. No vaccines and antiviral drugs are available. Herein the use of an RNA polymerase ...I-driven RSV minigenome for analyzing RSV replication and screening anti-RSV drugs was investigated. The RNA polymerase I(Pol I) was used to transcribe RSV minigenome from the constructed plasmid, designated p HM-RSV-Gluc, of minigenome c DNA which comprised trailer region, gene start sequence(GS), reverse complementary copy of Gaussia luciferase(Gluc) gene, gene end sequence(GE), and leader region in the direction of 5’–3’end and was flanked by promoter and terminator of Pol I. The expression of Gluc was confirmed in p HM-RSV-Gluc transfected HEp-2 cells following RSV infection and had the characteristics of dose-dependent, which provided a rapid, sensitive, and quantitative method for quantifying virus titers and screening antiviral drugs.
Human respiratory syncytial virus（RSV） is an important pediatric pathogen of lower respiratory tract worldwide. No vaccines and antiviral drugs are available. Herein the use of an RNA polymerase ...I-driven RSV minigenome for analyzing RSV replication and screening anti-RSV drugs was investigated. The RNA polymerase I（Pol I） was used to transcribe RSV minigenome from the constructed plasmid, designated p HM-RSV-Gluc, of minigenome c DNA which comprised trailer region, gene start sequence（GS）, reverse complementary copy of Gaussia luciferase（Gluc） gene, gene end sequence（GE）, and leader region in the direction of 5＇–3＇end and was flanked by promoter and terminator of Pol I. The expression of Gluc was confirmed in p HM-RSV-Gluc transfected HEp-2 cells following RSV infection and had the characteristics of dose-dependent, which provided a rapid, sensitive, and quantitative method for quantifying virus titers and screening antiviral drugs.
Objective The aim of this study was to analyze and evaluate 1.32-μm and 1.06-μm neodymium-doped yttrium aluminum garnet (Nd:YAG) lasers for use in liver and gastroepiploic vessel vaporization and ...coagulation.Methods The effects of 1.32-μm and 1.06-μm Nd:YAG lasers were compared for gastroepiploic vessel hemostasis in porcine liver.Results The results were observed and measured under the same parameters and dose conditions.The 1.32-μm laser showed greater vaporization width and depth than the 1.06-μm laser. Both lasers controlled active bleeding. The coagulation band with the 1.32-μm laser was thinner than with the 1.06-μm laser, at nearly 3 mm. After cutting of 1- and 2-mm porcine vessels, no grossly visible bleeding was apparent. Intravascular thrombus was visible under the microscope. The length of vessel thrombosis in the experimental group was 2 mm and the diameter was 2 mm; the control group exhibited thrombi as 2.3-4.9 mm in length. Thrombosis completely blocked the blood vessels.Conclusion The 1.32-μm laser had greater vaporization capability than the 1.06-μm laser and achieved hemostasis requirements for vessels less than 2 mm in diameter.
High abundant sulfur-containing steroids were identified and detected in saturate hydrocarbon fractions of heavy oil with a high sulfur content in the Jinxian Sag, Bohai Bay Basin, North China. These ...sulfur-containing steroids were structurally merged into the D-ring of steroid nucleus with thiophene ring and/or combined into the C-22 in the side-chain. Based on the previous reports of sulfur-containing steroids with methylthio- steroids and intra-molecular form, four formation mechanisms of sulfur-containing steroids and diagenetic pathway of steroids under S-rich conditions were proposed in this paper according to the double bond positions in the sterene compounds. Hydrogenation and sulfurization both occurred in the diagenetic pro- cesses of olefinic bond in the side-chain of steroids： abiogenic chemical hydrogenation of H2S and HS- leads to the formation of regular steranes; a successful sulfurization process leads to the formation of the side-chain sulfur-containing steroids where- as unsuccessful cyclization and/or sulfurization result in the generation of short-chain steranes. This kind of mechanism of hy- drogenation/sulfurization of side-chain olefinic bond provides a potential genesis clue for the occurrence of high abundance of short-chain steranes （higher than the common regular steroids, phytane and n-alkanes） in S-rich heavy oils and source rocks in the Jinxian Sag, Bohai Bay Basin, North China.
Aim
This study examined the correlation among turnover intention, emotional intelligence and job burnout in male nurses and determined its influencing factors.
Background
The number of male nurses ...has increased in China; however, the turnover rate is very high. Nurses’ turnover intention is related to job burnout and emotional intelligence.
Introduction
Recent studies have shown that job burnout and emotional intelligence are related to medical and health institution employees’ intention to leave their jobs. It is not clear if the same conclusions can be drawn about male nurses.
Methods
For this cross‐sectional study, 627 male nurses were recruited from across China between May and July 2018. Data were collected through an online questionnaire, and Pearson's product‐moment correlation coefficient and multiple linear regression were performed to analyse the data.
Results
There was a weak negative, moderate positive and moderate negative correlation between turnover intention and emotional intelligence, turnover intention and job burnout, and emotional intelligence and job burnout, respectively. Factors that significantly affected turnover intention among male nurses included job burnout, young age, lack of interest in nursing and working in the emergency department.
Conclusion
The study revealed the factors that affected male nurses’ turnover intention and the relationships between turnover intention, emotional intelligence and job burnout.
Implications for Nursing Management and Social Policy
Hospital managers should provide necessary help and support to reduce male nurse turnover rates and incorporate emotional intelligence training. The policy should eliminate the unfair college admission practices for students choosing nursing majors, raise the nursing profession's salaries and vigorously develop specialty nursing. In addition, diversified values should be promoted, and stereotypes of male nurses in nursing should be broken.
CuOx catalysts supported on mesoporous alumina microspheres with hierarchical structures and high surfaces are synthesized by a spray-drying method. The CuOx catalysts are ultrasmall (1–3 nm), ...bivalent (Cu+/Cu2+ ratio 0.7), and sintering- and oxidation-resistant. They show high performance in catalytic ozonation of phenol. The hydroxyl groups and Cu+/Cu2+ couples cooperatively accelerate O3 decomposition to generate radicals for phenol degradation and mineralization.
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•CuOx catalysts supported on defect-rich mesoporous alumina microspheres are synthesized.•They possess uniform sizes, hierarchical structures, high surfaces and uniform mesopores.•The CuOx species are ultrasmall (1–3 nm), bivalent (Cu+/Cu2+ ratio 0.7), and sintering- and oxidation-resistant.•High performance in catalytic ozonation of phenol with structure-performance relationship studied.•Hydroxyl groups and Cu+/Cu2+ couples cooperatively accelerate O3 decomposition generating radicals.
Supported copper oxides with well-dispersed metal species, small size, tunable valence and high stability are highly desirable in catalysis. Herein, novel copper oxide (CuOx) catalysts supported on defect-rich mesoporous alumina microspheres are developed using a spray-drying-assisted evaporation induced self-assembly method. The catalysts possess a special structure composed of a mesoporous outer layer, a mesoporous-nanosphere-stacked under layer and a hollow cavity. Because of this special structure and the defective nature of the alumina support, the CuOx catalysts are ultrasmall in size (1 ~ 3 nm), bivalent with a very high Cu+/Cu2+ ratio (0.7), and highly stable against sintering and oxidation at high temperatures (up to 800 °C), while the wet impregnation method results in CuOx catalysts with much larger sizes (~15 nm) and lower the Cu+/Cu2+ ratios (~0.29). The catalyst formation mechanism through the spray drying method is proposed and discussed. The catalysts show remarkable performance in catalytic ozonation of phenol wastewaters. With high-concentration phenol (250 ppm) as the model organic pollutant, the optimized catalyst delivers promising catalytic performance with 100% phenol removal and 53% TOC removal in 60 min, and a high cyclic stability. Superoxide anion free radicals (⋅O2–), singlet oxygen (1O2) and hydroxyl radicals (⋅OH) are the predominant reactive species. A detailed structure-performance study reveals the surface hydroxyl groups and Cu+/Cu2+ redox couples play cooperatively to accelerate O3 decomposition generating reactive radicals. The plausible catalytic O3 decomposition mechanism is proposed and discussed with supportive evidences.
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