Event-related potentials in a Go/Nogo task of abnormal response inhibition in heroin addicts

Inhibitory control dysfunction is regarded as a core feature in addicts. The major objective of this study was to explore the time course of response inhibition in chronic heroin addicts and provide the neu-rophysiological evidence of their inhibitory control dysfunction. The amplitudes and latencies of ERP components were studied in fourteen heroin addicts (mean duration of heroin use being (13.54±5.71) years (Mean±SD), average abstinence being ((4.67±6.44) months)) and fourteen matched healthy con-trols with a visual Go/Nogo task. Our results showed that heroin addicts demonstrated significantly larger Go-N2 amplitudes which results in a decreased N2 Go/Nogo effect, but no statistically significant differences were found between heroin addicts and controls in P3. The ERP data suggest that fronto-central areas of heroin addicts were impaired during the inhibition process (200—300 ms) and over-activated to targets. The impaired early process might reflect an abnormal conflict monitoring process in heroin addicts. These results consolidate the inhibitory control dysfunction hypothesis in chronic heroin users.     

Triad 1 induces apoptosis by p53 activation

Triad 1 (2 RING [really interesting new gene] fingers and DRIL [double RING finger linked] 1) is an E3 ligase that induces apoptosis and clonogenic inhibition in myeloid cells through Gfi-1 stabilization. Here we demonstrate that Triad 1 induces apoptosis in several cancer cell lines including MCF7, A549, U2OS, and HCT 116 p53^+/+ cells via its RING ligase activity. Interestingly, in these cancer cells, Triad 1-induced apoptosis is not mediated by Gfi-1 stabilization but is instead p53-dependent. Moreover, Triad 1 promotes transactivation of p53. These results suggest that Triad 1 can induce apoptosis through its ligase activity via p53 activation.     

Expression of BjMT2, a metallothionein 2 from Brassica juncea, increases copper and cadmium tolerance in Escherichia coli and Arabidopsis thaliana, but inhibits root elongation in Arabidopsis thaliana seedlings

The protective function of a plant type-2 metallothionein was analysed after expression in Escherichia coli and in Arabidopsis thaliana seedlings. BjMT2 from Brassica juncea was expressed in E. coli as a TrxABjMT2 fusion protein. After affinity chromatography and cleavage from the TrxA domain, pure BjMT2 protein was obtained which strongly reacted with the thiol reagent monobromobimane. Escherichia coli cells expressing the TrxABjMT2 fusion were more tolerant to Cu2+ and Cd2+ exposure than control strains. Likewise, when BjMT2 cDNA was expressed in A. thaliana under the regulation of the 35S promoter, seedlings exhibited an increased tolerance against Cu2+ and Cd2+ based on shoot growth and chlorophyll content. Analysis of transiently transformed cells of A. thaliana and tobacco leaves by confocal laser scanning microscopy (CLSM) revealed exclusive cytosolic localization of a BjMT2::EGFP (enhanced green fluorescent protein) fusion protein in control and heavy metal-exposed plant cells. Remarkably, ectopic expression of BjMT2 reduced root growth in the absence of heavy metal exposure, whereas in the presence of 50 or 100 microM Cu2+ root growth in control and transgenic lines was identical. The results indicate that in A. thaliana, root and shoot development are differentially affected by ectopic expression of BjMT2.     

Exploring the expression bar code of SAA variants for gastric cancer detection

We reported an integrated platform to explore serum protein variant pattern in cancer and its utility as a new class of biomarker panel for diagnosis. On the model study of serum amyloid A (SAA), we employed nanoprobe‐based affinity mass spectrometry for enrichment, identification and quantitation of SAA variants from serum of 105 gastric cancer patients in comparison with 54 gastritis patients, 54 controls, and 120 patients from other cancer. The result revealed surprisingly heterogeneous and most comprehensive SAA bar code to date, which comprises 24 SAA variants including SAA1‐ and SAA2‐encoded products, polymorphic isoforms, N‐terminal–truncated forms, and three novel SAA oxidized isotypes, in which the variant‐specific peptide sequence were also confirmed by LC‐MS/MS. A diagnostic model was developed for dimension reduction and computational classification of the 24 SAA‐variant bar code, providing good discrimination (AUC = 0.85 ± 3.2E?3) for differentiating gastric cancer group from gastritis and normal groups (sensitivity, 0.76; specificity, 0.81) and was validated with external validation cohort (sensitivity, 0.71; specificity, 0.74). Our platform not only shed light on the occurrence and modification extent of under‐represented serum protein variants in cancer, but also suggested a new concept of diagnostic platform by serum protein variant profile.     

Toxicity of A Novel Neonicotinoid Insecticide Paichongding to Earthworm Eisenia fetida

Traditional neonicotinoid insecticides are used worldwide. Paichongding (IPP), as a novel neonicotinoid pesticide, has been widely used in China. However, the ecotoxicity of IPP to non-target invertebrates in soil ecosystem has not been reported yet. In this study, acute toxicity of IPP to earthworm Eisenia fetida, as well as the antioxidant response after IPP exposure, was evaluated. In the filter paper contact test, the LC₅₀ at 24 hr and 48 hr for IPP were 14.98 μg/cm² and 7.59 μg/cm², respectively. In artificial soil test, the LC₅₀ (lethal concentration) at 14 days and 28 days for IPP were 541.07 mg/kg and 238.51 mg/kg, respectively. The LC₅₀ of IPP is much higher than that of traditional neonicotinoid insecticides. However, earthworm body weight assessment demonstrated that the growth of earthworm was inhibited by extended exposure to IPP at sublethal doses. The activities of antioxidative enzymes superoxide dismutase and catalase in earthworms were significantly induced after IPP exposure. Malondialdehyde, a biomarker of lipid peroxidation, was also increased after IPP exposure. Although the results indicated that IPP had potentially adverse effect on earthworms, its toxicity was much lower than traditional neonicotinoids.     

Genetic regulation by non-coding RNAs

Large scale cDNA sequencing and genome tiling array studies have shown that around 50% of genomic DNA in humans is transcribed, of which 2% is translated into proteins and the remaining 98% is non-coding RNAs (ncRNAs). There is mounting evidence that these ncRNAs play critical roles in regulating DNA structure, RNA expression, protein translation and protein functions through multiple genetic mechanisms, and thus affect normal development of organisms at all levels. Today, we know very little about the regulatory mechanisms and functions of these ncRNAs, which is clearly essential knowledge for understanding the secret of life. To promote this emerging research subject of critical importance, in this paper we review (1) ncRNAs' past and present, (2) regulatory mechanisms and their functions, (3) experimental strategies for identifying novel ncRNAs, (4) experimental strategies for investigating their functions, and (5) methodologies and examples of the application of ncRNAs.     

Demecolcine-induced enucleation of sheep meiotically maturing oocytes

The objective of this study was to investigate the possible effect of demecolcine, a microtubule-disrupting reagent, on induced enucleation (IE) of sheep meiotically maturing oocytes. Immunofluorescent staining with anti-tubulin antibodies was used to examine the spindle status of the oocytes. When the oocytes with intact germinal vesicles (GV) were cultured in the medium containing various concentrations of demecolcine (0.01 to 0.4 microg.mL-1) for 20 to 22 h, the spindle microtubule organization and first polar body (PB1) extrusion were inhibited by demecolcine in a dose-dependent manner. The highest IE rate (58.1%) was from the treatment with 0.04 microg.mL-1 demecolcine. Demecolcine treatment applied after germinal vesicle breakdown (GVBD) or at metaphase (M) yielded a PB1 extrusion rate and IE efficiency similar to the treatment applied at the onset of maturation. Analysis by immunofluorescence showed that both nonspindle microtubules and spindle microtubules were significantly disorganized by demecolcine. Combination treatment with demecolcine and cycloheximide (CHX) or 6-dimethylaminopurine (6-DMAP) led to single pronuclear formation rather than PB1 extrusion. When demecolcine-treated oocytes were transferred into demecolcine-free medium, the ability to extrude PB1 was quickly restored and a 72.1% IE rate was obtained following such treatment. These results demonstrate that demecolcine can be used as a potential reagent for induced enucleation of sheep meiotically maturing oocytes and may greatly facilitate research in nuclear transfer.     

Climate warming and atmospheric deposition affect seed viability of common juniper (<Emphasis Type="Italic">Juniperus communis</Emphasis>) via their impact on the nutrient status of the plant

Global environmental change is increasingly affecting species worldwide. One of the emblematic casualties among plants in several European countries is common juniper (Juniperus communis). Many populations of common juniper throughout its distribution range are declining. The relative lack of viable seed production, resulting in low probabilities for successful natural regeneration, is one of the main reasons for this decline. Climate warming and elevated atmospheric depositions have been shown to negatively affect seed viability of common juniper, but our understanding of the underlying mechanisms remains scarce. One possible pathway is via changes in the plant nutrient status that, in turn, may affect seed viability. Here we took advantage of large-scale gradients in climate and atmospheric depositions between central Sweden and northern Spain, and analysed foliar nutrient concentrations and stoichiometry and seed viability in 20 juniper populations spread across Europe. Our results show that increasing temperatures can negatively affect needle N and P concentrations while enhanced potentially acidifying depositions resulted in lower foliar N and Ca concentrations. Needle C:N ratios increased with higher temperature, acidifying depositions and precipitation. By linking these patterns to seed viability, we found that low needle P, Ca and Mg concentrations were related to low seed viability. Thus, a shortage of these key elements during seed development and seed nutrient storage, can lead to anomalies and seed abortion. These findings help to explain the low seed viability of juniper in Europe and may help to assist land managers to take urgently needed conservation actions.     

共表达口蹄疫病毒衣壳前体蛋白P1-2A基因和蛋白酶3C基因牛肾细胞株的筛选及稳定性

[目的]筛选稳定表达口蹄疫病毒衣壳蛋白的牛肾细胞(Madin-Darby bovinekidney,MDBK)株.[方法]采用聚合酶链式反应(Polymerase chain reaction,PCR)方法从重组质粒pMD-P1-2A和pMD-3C中分别扩增口蹄疫病毒衣壳前体蛋白P1-2A基因和蛋白酶3C基因,将两基因依次插入逆转录病毒载体pBABE-puro.重组逆转录病毒载体pBABE-puro/P1-2A-3C和pVSV-G质粒载体用脂质体介导共转染GP2-293包装细胞.产生的重组逆转录病毒感染MDBK细胞后使用嘌呤霉素筛选抗性细胞.利用克隆环套取法得到单克隆细胞.经间接免疫荧光和酶联免疫吸附测定(Enzyme-linkedimmunosorbent assay,ELISA)方法检测MDBK细胞中衣壳蛋白的表达,并在电镜下观察口蹄疫病毒空衣壳.[结果]成功筛选到稳定表达口蹄疫病毒衣壳蛋白的MDBK细胞株,衣壳前体蛋白P1-2A在蛋白酶3C裂解作用下正确组装成空衣壳.[结论]该研究为口蹄疫亚单位疫苗的研制提供了实验材料.