Fate and Phytotoxicity of CeO2 Nanoparticles on Lettuce Cultured in the Potting Soil Environment

Cerium oxide nanoparticles (CeO₂ NPs) have been shown to have significant interactions in plants. Previous study reported the specific-species phytotoxicity of CeO₂ NPs by lettuce (Lactuca sativa), but their physiological impacts and vivo biotransformation are not yet well understood, especially in relative realistic environment. Butterhead lettuce were germinated and grown in potting soil for 30 days cultivation with treatments of 0, 50, 100, 1000 mg CeO₂ NPs per kg soil. Results showed that lettuce in 100 mg·kg^-1 treated groups grew significantly faster than others, but significantly increased nitrate content. The lower concentrations treatment had no impact on plant growth, compared with the control. However, the higher concentration treatment significantly deterred plant growth and biomass production. The stress response of lettuce plants, such as Superoxide dismutase (SOD), Peroxidase (POD), Malondialdehyde(MDA) activity was disrupted by 1000 mg·kg^-1 CeO₂ NPs treatment. In addition, the presence of Ce (III) in the roots of butterhead lettuce explained the reason of CeO₂ NPs phytotoxicity. These findings demonstrate CeO₂ NPs modification of nutritional quality, antioxidant defense system, the possible transfer into the food chain and biotransformation in vivo.     

NOD1 modulates decidual stromal cell function to maintain pregnancy in the early trimester

We sought to explore the functions and modulated factors of NOD1 in normal decidual stromal cells (DSCs) derived from the first trimester pregnancy and whether existed different expression of NOD1 between normal and unexplained recurrent pregnancy loss (URPL) in DSCs. Twenty‐six patients with normal pregnancies that required abortion and 12 URPL patients at first trimester were enrolled for the study. As a result, we found lower levels of NOD1 in the DSCs derived from URPL compared with those from normal early trimester pregnancy. Furthermore, increased NOD1 expression in the normal DSCs induced apoptosis and increased monocyte chemotactic protein‐1 (MCP‐1) and IL‐1β (interleukin 1 beta) secretion but decreased their invasion capacity. In addition, several cytokines such as IL‐1β, tumour necrosis factor‐alpha (TNF‐α), interferon‐gamma (IFN‐γ), and interleukin‐17 (IL‐17) were present at the maternal‐fetal interface in RPL and were found to regulate NOD1 expression in primary DSCs. Our study indicates that RPL may be associated with NOD1 aberrant expression in DSCs, which plays a significant role in maintaining pregnancy via infection control and regulation of immune responses that might affect the pregnancy outcome. We expect that our results will bring more comprehensively understanding about the connection between NOD1 and RPL for researchers.     

内蒙古羊草草原植物群落地上初级生产力时间动态对降水变化的响应

植被生产力对水热因子的反应是气候 -植被关系研究的焦点之一。利用 1981～ 1994年的固定围栏样地植物群落调查数据及同期降水资料 ,分析了羊草草原群落地上初级生产力和降水的年际变化特征及植物群落地上初级生产力的时间动态与降水年际变化的相互关系。结果表明 ,羊草草原年降水以及月降水的年际波动明显 ;年内降水分配不均匀 ,降水集中分布于 6～ 8月份。月均降水以 7月份最高 ,基本呈对称分布。群落地上初级生产力年际间变化介于年降水与月降水的年际变化之间。影响群落地上初级生产力时间动态最显著的因子是植物生长周期内前一年 10月至当年 8月的累积降水 ,而与年降水和月降水无显著相关。群落地上初级生产力时间动态对累积降水波动的反应呈显著的二次曲线关系 ,与空间尺度上地上初级生产力与年降水呈线性相关关系不同。因此 ,降水波动对羊草草原地上初级生产力的影响是一个累积效应 ,确定对植物生长产生影响的有效降水时间对建立羊草草原生产力模型关系具有十分重要的意义。     

Synthesis and properties of sulfhydryl-reactive near-infrared cyanine fluorochromes for fluorescence imaging

Near-infrared fluorochromes (NIRF) are useful compounds for diverse biotechnology applications and for in vivo biomedical imaging. Such NIRF must have high quantum yield, be biocompatible, and be conjugatable to a wide variety of proteins, peptides, and other affinity ligands. Here, we describe the synthesis of four new nonsymmetrical sulfhydryl-reactive cyanine NIRF with excellent optical and chemical properties. Each fluorochrome was designed to contain an iodoacetamido group that reacts specifically with sulfhydryl-containing molecules. The synthesized fluorochromes were used to label model peptides and sulfhydryl-containing biomolecules.     

Cytokine and Antibody Based Diagnostic Algorithms for Sputum Culture-Positive Pulmonary Tuberculosis

Background

Tuberculosis (TB) is one of the most serious infectious diseases globally and has high mortality rates. A variety of diagnostic tests are available, yet none are wholly reliable. Serum cytokines, although significantly and frequently induced by different diseases and thus good biomarkers for disease diagnosis and prognosis, are not sufficiently disease-specific. TB-specific antibody detection, on the other hand, has been reported to be highly specific but not sufficiently sensitive. In this study, our aim was to improve the sensitivity and specificity of TB diagnosis by combining detection of TB-related cytokines and TB-specific antibodies in peripheral blood samples.

Methods

TB-related serum cytokines were screened using a human cytokine array. TB-related cytokines and TB-specific antibodies were detected in parallel with microarray technology. The diagnostic performance of the new protocol for active TB was systematically compared with other traditional methods.

Results

Here, we show that cytokines I-309, IL-8 and MIG are capable of distinguishing patients with active TB from healthy controls, patients with latent TB infection, and those with a range of other pulmonary diseases, and that these cytokines, and their presence alongside antibodies for TB-specific antigens Ag14-16kDa, Ag32kDa, Ag38kDa and Ag85B, are specific markers for active TB. The diagnostic protocol for active TB developed here, which combines the detection of three TB-related cytokines and TB-specific antibodies, is highly sensitive (91.03%), specific (90.77%) and accurate (90.87%).

Conclusions

Our results show that combining detection of TB-related cytokines and TB-specific antibodies significantly enhances diagnostic accuracy for active TB, providing greater accuracy than conventional diagnostic methods such as interferon gamma release assays (IGRAs), TB antibody Colloidal Gold Assays and microbiological culture, and suggest that this diagnostic protocol has potential for clinical application.     

Impact of Childhood Abuse on the Risk of Non-Suicidal Self-Injury in Mainland Chinese Adolescents

Background

Childhood abuse has been associated with significant increases in non-suicidal self-injury (NSSI) behaviors in adolescents; however, only general definitions of this risk indicator have been examined. This study identified relationships between specific forms of childhood abuse and NSSI in mainland Chinese adolescents.

Method

A total of 14,221 cases were retained from an epidemiological study involving adolescents from junior and senior middle schools. Information relating to the perpetrator, perceived harm, timing of exposure to different types of childhood abuse, and NSSI were obtained. Logistic regression was used to analyze relationships between each form of childhood abuse and NSSI.

Results

Approximately 51.0% of the students reported at least one abusive childhood experience. Nearly one in four students (24.9%) reported that they had engaged in NSSI in the past 12 months. Each type of childhood abuse, occurring at any time within the first 16 years of life, especially in situations of continuous exposure, was significantly associated with NSSI. A significant graded relationship was found between number of abusive childhood experiences and NSSI. Students maltreated by parents or others were at high risk of engaging in NSSI, the risk was greater in students maltreated by both; students who had been exposed to childhood abuse with no perceived harm still demonstrated an elevated risk for NSSI. The pattern of associations did not vary by gender.

Conclusions

These findings suggest that experiencing any of various forms of childhood abuse should be considered a risk factor for NSSI during adolescence. Further research should focus upon psychosocial, neural, and genetic factors that might moderate or mediate the onset of NSSI in adolescents who have experienced childhood abuse.     

Molecular dynamics study of the proposed proton transport pathways in [FeFe]-hydrogenase

Possible proton transport pathways in Clostridium pasteurianum (CpI) [FeFe]-hydrogenase were investigated with molecular dynamics simulations. This study was undertaken to evaluate the functional pathway and provide insight into the hydrogen bonding features defining an active proton transport pathway. Three pathways were evaluated, two of which consist of water wires and one of predominantly amino acid residues. Our simulations suggest that protons are not transported through water wires. Instead, the five-residue motif (Glu282, Ser319, Glu279, H₂O, Cys299) was found to be the likely pathway, consistent with previously made experimental observations. The pathway was found to have a persistent hydrogen bonded core (residues Cys299 to Ser319), with less persistent hydrogen bonds at the ends of the pathway for both H₂ release and H₂ uptake. Single site mutations of the four residues have been shown experimentally to deactivate the enzyme. The theoretical evaluation of these mutations demonstrates redistribution of the hydrogen bonds in the pathway, resulting in enzyme deactivation. Finally, coupling between the protein dynamics near the proton transport pathway and the redox partner binding regions was also found as a function of H₂ uptake and H₂ release states, which may be indicative of a correlation between proton and electron movement within the enzyme.