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The previous studies show soil microbes play a key role in the material and nutrient cycles in the forest ecosystem, but little is known about how soil microbes respond to plant distribution, especially in the soil bacterial community in woody bamboo forests. Cephalostachyum pingbianense (Hsueh & Y.M. Yang ex Yi et al.) D.Z. Li & H.Q. Yang, 2007 is known as the only bamboo species producing shoots all year round in natural conditions. Endemic to the Dawei mountain in Yunnan of China, this species is a good case to study how soil bacteria respond to plant endemic distribution. In this work, we assayed the soil chemical properties, enzyme activity, changes in the bacterial community along the distribution range of the C. pingbianense forest. The results showed that soil nutrients at the range edge were nitrogen-rich but phosphorus-deficient, and soil pH value and soil urease activity were significantly lower than that of the central range. No significant difference was detected in soil bacterial diversity, community composition, and function between the central and marginal range of C. pingbianense forest. Notably, the relative abundance of heterotrophy bacteria, such as Variibacter and Acidothermus, in the soil of the C. pingbianense forest was significantly higher than that of the outside range, which may lead to a higher soil organic carbon mineralization rate. These results imply that abundant heterotrophy bacteria were linked to the endemism and full-year shooting in C. pingbianense. Our study is amongst the first cases demonstrating the important role of heterotrophy bacteria in the distribution formation of endemic woody bamboos in special soil habitats, and provides insight into germplasm conservation and forest management in woody bamboos.

Research letter: The cardiovascular toxicity of electronic cigarettes (e-cigarettes) is not well understood, and population data assessing the cardiovascular effects of e-cigarette use are sparse. In the present study, we used nationally represen-tative data to examine the association of cigarette and e-cigarette use behaviors with biomarkers of inflammation and oxidative stress. Inflammation and oxidative stress are key contributors of smoking-induced cardiovascular disease, and related biomarkers have been studied as predictive factors for cardiovascular events. In this nationally representative population study of adults, we observed no difference in inflammatory and oxidative stress biomarkers between exclusive e-ciga-rette users and nonusers (no cigarettes or vaping), and levels were lower in exclusive e-cigarette users relative to exclusive smokers. These findings are consistent with recent population studies of inflammatory biomarker and toxicant exposure in users of e-cigarettes and ciga-rettes and highlight the importance of completely re-placing cigarette smoking with e-cigarettes or quitting the use of both products for cigarette smokers to derive potential health benefits.

Aconitine, a major aconitum alkaloid, is well known for its high toxicity that induces severe arrhythmias and neurological symptoms. One mechanism of aconitine-induced toxic responses is the induction of apoptosis. Apoptosis and autophagy are interconnected processes and the two pathways share critical components. In this study, we investigated the role of autophagy in aconitine-induced toxicity using mouse model. 120 mice were randomly divided into 4 experimental groups (normal saline), low dose group (0.14 μmol/L), medium dose group (0.28 μmol/L) and high dose group (0.56 μmol/ L). 30 mice in each group were administered with aconitine (lavage) for 30 days. The livers were collected for analysis of autophagy-related proteins by Western blotting. The expression of LC3II/LC3I ratio and Beclin 1 were found to increase and then decrease with the highest expression at 10 days and the p62 showed a time-dependent decreases. Autophagy is regulated by the mTOR pathway, we further analyzed the effects of aconitine on this pathway and found aconitine inhibited, phosphorylation of p-PI3K, p-Akt and p-mTOR. The p-p70s6k and p-4EBP1 which are downstream of mTOR were concomitantly decreased. These results suggest that aconitine induce autophagy in mouse liver. The PI3K/Akt/mTOR signaling pathway is involved in the regulation of aconitine-induced autophagy in the liver of mice.

Cd and Pb are a toxic environmental pollutant, and their elevated concentrations in the waters and soils could exert detriment effects on human health by food chain. In order to evaluate the capacity to heavy metal accumulation and the physiochemical responses of two Salix genotypes, a 35-day hydroponic seedling experiment was implemented with Salix matsudana Koidz. 'Shidi1' (A42) and Salix psammophila C. 'Huangpi1' (A94) under different concentrations of Cd (15 and 30 μM) or Pb (250 and 300 μM). The results showed that the biomass of A94 severely reduced more than that of A42. The accumulation ability of Cd in different plant organs followed the sequence of leaves > roots > stems. Pb primarily accumulated in the roots for both Salix genotypes (54.27 mg g-1 for A42 and 54.52 mg g-1 for A94). Translocation factors based on accumulation (TF') for Cd were more than 8.0, while TF's for Pb were less than 1.0 in both A42 and A94, implying they could be applied in the phytoremediation of Cd-contaminated sites due to their stronger ability to Cd phytoextraction. The stress of Cd or Pb significantly increased malondialdehyde (MDA) contents and increased photosynthetic rates in leaves of two Salix genotypes. Transpiration rates of willow were positively correlated with its Cd translocation. Both catalase (CAT) and peroxidase (POD) activities were suppressed, while the superoxide dismutase (SOD) was boosted with increasing Cd and Pb levels in the leaves and roots of the two willow genotypes, suggesting SOD plays an important role in the removal of ROS. The inconsistency of the changes in enzyme activity suggests that the integrated antioxidative mechanisms regulate the tolerance to Cd and Pb stress.

"Movie" is an appellation of early Chinese films. "Shadow" uses light as a pen to write a summary of screen behavior; "Drama" is an abstract meaning of plot and dramatic conflict. "Film drama" reflects the creative idea and direction of early Chinese films, and also reflects the origin between it and drama. In the history of Chinese film, this unique concept of national film was formed through multiple washes of subjective choice and the promotion of historical opportunities, and has gradually become the dominant concept of art and film in the development of Chinese film.

Ectomycorrhizal fungi (EMF), which form symbiotic ectomycorrhiza with tree roots, mediate heavy metal tolerance of host plants. To investigate the roles of EMF in the growth, modulation of oxidative stress, and cadmium (Cd) accumulation and translocation in Quercus acutissima seedlings, ectomycorrhizal seedlings inoculated with Suillus luteus were treated with different Cd concentrations (0.1, and 5 mg kg−1) for 14 days. EMF accelerated seedling growth and Cd accumulation in roots under the highest Cd concentration of 5 mg kg−1. Catalase (CAT), ascorbate peroxidase (APX), and glutathione reductase (GR) activities increased in the leaves of ectomycorrhizal seedlings under the highest Cd concentration. Superoxide dismutase (SOD) trended to increase under both Cd concentrations. Although reduced glutathione (GSH) increased after inoculation of EMF under both Cd concentrations, the release of malondialdehyde increased in the leaves and roots under the highest Cd concentration, indicating that the defense role of EMF in Q. acutissima depends on the Cd concentration. These results indicate that EMF mitigate Cd stress by promoting plant growth and nutrient uptake while modulating the antioxidant system to reduce oxidative stress.

Flipped classroom has received much attention in medical education. The aim of this study was to evaluate the efficacy of flipped classroom combing with human anatomy web-based learning system in anatomy education. A total of 89 freshmen in medical specialty were enrolled and randomly allocated into either the experimental group (receiving the flipped classroom with human anatomy web-based learning system, n = 45) or control group (receiving the traditional classroom teaching, n = 44). A pre-quiz and a post-quiz were conducted before and after the classes, respectively. The improvement in scores between groups was compared. A 5-point Likert scale questionnaire was used to evaluate perceptions and experience. The mean pre-quiz scores of the 2 groups were comparable (all P > .05). However, the mean post-quiz score in the experimental group was significantly higher than that in the control group (91.44 ± 6.25 vs 86.13 ± 11.67, P

Monolayer VS2 has two common stable phases, 2H-phase and 1T-phase. Based on first-principles calculations, we studied the optical properties of 2D-VS2, including their dielectric functions, absorption coefficients, refraction indexes and energy loss functions. Also, we fully analyzed the relationship between the electronic structure and the optical characteristics of 2D-VS2. We found that the differences of density of states are the fundamental reasons for the differences of the two phase optical absorption behavior.

Swainsonine is a major toxic ingredients of locoweed plants, ingestion of these plants may cause locoism in livestock characterized by extensive cellular vacuolar degeneration of multiple tissues. However, so far, the mechanisms responsible for vacuolar degeneration induced by SW are not known. In this study, we investigated the role of autophagy in SW-induced TCMK-1 cells using Western blotting, transmission electron microscopy, immunofluorescent microscopy and qRT-PCR. The results showed that SW treatment increased the levels of LC3-II. The co-localization of LC3-II and lysosomal protein LAMP-2 results suggested that SW treatment does not interfere with fusion between autophagosome and lysosome. TEM results indicated that SW induced aggregation of the lysosome around the autophagosome. In addition, SW treatment suppressed p-PI3K, p-Akt, p-mTOR, p-p70S6K and p-4EBP1 level. In conclusion, SW induced autophagy via pI3K/AKT/mTOR signaling pathway and revealed the role of autophagy in causing the SW toxicity characterized by the vacuolar degeneration.

Pregnancy hypertensive disorders (PHDs) are considered to be a multifactorial and multisystemic disorder with a genetic predisposition. Alterations in the renin–angiotensin system are considered to play a significant role in the pathogenesis of the PHDs. However, results from published studies on the association between the angiotensin II type-1 receptor (AT1R) A1166C (rs5186) gene polymorphism and the risk of PHDs are conflicting. The aim of this meta-analysis was to investigate whether an association exists between AT1R A1166C gene polymorphism and PHDs in epidemiologic studies. We searched the PubMed, China National Knowledge Infrastructure (CNKI), and Chinese Biomedicine Literature (CBM) databases from their inception to July 2012. A total of 18 case–control studies, including a total of 1635 cases and 1934 controls, were available for this analysis. A significantly positive correlation was observed between the C allele and the AC/CC genotypes with PHDs in an overall comparison. In the subgroup analysis by ethnicity, the results suggested that the C allele and the AC/CC genotypes were associated with risk of PHDs in Asians. Our findings indicate that the AT1R gene 1166C allele and the AC/CC genotypes were positively associated with the PHDs, especially in Asians. However, well-designed multicenter studies with a larger sample size should be conducted to confirm the results.