Synthesis, crystal structure and optical properties of a new lead bismuth borate

A new phase of the compound PbBiBO₄ has been successfully synthesized via the standard solid-state reaction, and the crystal structure has been determined from X-ray monocrystal diffraction data. It crystallizes in orthorhombic space group Cmca (No. 64) with lattice constants a = 10.782(3) Å, b = 10.502(3) Å, c = 7.477(2) Å, Z = 8. The crystal structure is characterized by a three-dimensional structure consisting of BiO₆ octahedra, PbO₄ tetrahedra and BO₃ triangles. The BiO₆ octahedra compose the layers through the O(2) atoms and O(3) atoms along the [1 0 1] direction, which connects the BO₃ trigonal groups by sharing the O(3) and two O(1) atoms and links the PbO₄ tetrahedra through the O(2) atoms. The UV–Vis–NIR Diffuse-Reflectance spectrum shows that the ultraviolet cutoff edge for the PbBiBO₄ crystal is about 310 nm. Functional groups in the sample were identified by Infrared spectrum.     

Oxidative stress induces H2AX phosphorylation in human spermatozoa

H2AX phosphorylation occurs following the induction of DNA double strand breaks (DSBs), thus collaborating with many other proteins to mediate important biological functions in somatic cells. In human spermatozoa, the present study showed that H(2)O(2) induced H2AX phosphorylation in a time- and dose-dependent manner. Moreover, such effect could be abolished by the phosphatidylinositol 3-kinase inhibitor wortmannin. Meanwhile, the neutral comet assay also revealed DSBs production in correlation with H2AX phosphorylation assessed by flow cytometry. Besides H2AX phosphorylation, two other collaborating proteins, Rad50 and 53BP1, were also generated in spermatozoa after H(2)O(2) exposure. However, unlike in somatic FL cells, there were no distinctive focuses, but rather a whole nuclei staining pattern of these three proteins in spermatozoa. Additionally, gammaH2AX (the phosphorylated form of H2AX) staining in spermatozoa persisted despite the fact of a decrease in the number of gammaH2AX foci in FL cells after H(2)O(2) removal. Collectively, these results demonstrate that oxidative stress can induce H2AX phosphorylation in human spermatozoa through DSB induction, and that gammaH2AX may be used as a sensitive, novel marker for such DSBs. Moreover, the surveillance system involving gammaH2AX, Rad50, and 53BP1 in human spermatozoa cannot function effectively in DNA repair, but this system may possess other biological functions in response to DSBs.     

健康鸡与患病鸡消化道中正常菌分布变化超微观察

利用扫描电镜观察健康鸡与患球虫病鸡消化道（嗉囊、回肠和盲肠部位）中正常菌群黏附状况发生的变化。结果表明,健康鸡消化道黏膜表面均匀覆盖着大量的正常菌群,黏膜完整,其中嗉囊表面黏附的乳酸杆菌最为致密;而患球虫病鸡消化道黏膜脱落,正常菌群明显减少,这是病鸡发生腹泻的主要原因。     

Mash-1在大鼠SVZa神经干细胞迁移流的发育学表达

目的了解在大鼠脑发育过程中,mash-1在SVZa神经干细胞迁移流通路中三个不同脑区内的表达模式。方法用RT-PCR和免疫荧光染色的方法观察在胚胎14d(E14),出生后0d(P0),生后7d(P7)3个不同发育阶段大鼠SVZa、RMS、OB3个区域mash-1的表达情况。结果RT-PCR显示在大鼠脑发育过程中SVZa、RMS、OB三个区域mash-1的mRNA均有不同程度的表达,在出生前后(P0)表达最高;免疫组化显示在大鼠脑发育成熟过程中,mash-1表达水平呈现复杂的时空表达模式,在胚胎期SVZa神经干细胞迁移流通路中表达密集,P0时期在嗅球有较高的表达,P7以后mash-1的表达水平普遍下降。结论mash-1可能主要参与调节大鼠SVZa神经干细胞分化过程,对其迁移和增殖也可能具有积极影响。     

Hepatitis C Virus Genotype Diversity among Intravenous Drug Users in Yunnan Province,Southwestern China

Background

Recently, high proportions (15.6%–98.7%) of intravenous drug users (IDUs) in China were found to be positive for hepatitis C virus (HCV). Yunnan Province is located in southwestern China and borders one of the world''s most important opium-producing regions, thus it is an important drug trafficking route to other regions of China.

Methodology/Principal Findings

Here, we assessed 100 HCV-positive plasma samples from IDUs who were enrolled through the Kunming Center for Disease Control and Prevention in 2012. HCV C/E1 fragments were PCR-amplified and sequenced. We identified eight HCV subtypes (1a, 1b, 3a, 3b, 6a, 6n, 6u and 6v), of which genotype 6 was most predominant (frequency, 47%) followed by genotypes 3 (41%) and 1 (12%). HCV subtypes 6n (30%) and 3b (29%) were most common and were identified in 59% of the IDUs. We compared HCV genotypes among IDUs in Yunnan Province with those from other regions and found that the distribution patterns of HCV genotypes in Yunnan Province were similar to those in southern China, but different from those in eastern China. However, the distribution patterns of HCV subtypes varied among Yunnan Province and southern China, despite the shared similar genotypes. A comparison of the current data with those previously reported showed that the frequency of HCV genotype 6 increased from 25% to 47% within 5 years, especially subtypes 6a (5% to 15%) and 6n (11.2% to 30%). In contrast, the frequencies of subtypes 3b and 1b decreased by almost 50% within 5 years.

Conclusion/Significance

Our results provided further information to support the assertion that drug trafficking routes influence HCV transmission patterns among IDUs in Yunnan Province. The frequency of HCV genotypes and subtypes changed rapidly among IDUs in Yunnan Province and subtypes 6a and 6n may have originated in Vietnam and Myanmar, respectively.     

Analysis of POFUT1 Gene Mutation in a Chinese Family with Dowling-Degos Disease

Dowling-Degos disease (DDD) is an autosomal dominant genodermatosis characterized by reticular pigmented anomaly mainly affecting flexures. Though KRT5 has been identified to be the causal gene of DDD, the heterogeneity of this disease was displayed: for example, POFUT1 and POGLUT1 were recently identified and confirmed to be additional pathogenic genes of DDD. To identify other DDD causative genes, we performed genome-wide linkage and exome sequencing analyses in a multiplex Chinese DDD family, in which the KRT5 mutation was absent. Only a novel 1-bp deletion (c.246+5delG) in POFUT1 was found. No other novel mutation or this deletion was detected in POFUT1 in a second DDD family and a sporadic DDD case by Sanger Sequencing. The result shows the genetic-heterogeneity and complexity of DDD and will contribute to the further understanding of DDD genotype/phenotype correlations and to the pathogenesis of this disease.     

Investigating the Temporal Patterns within and between Intrinsic Connectivity Networks under Eyes-Open and Eyes-Closed Resting States: A Dynamical Functional Connectivity Study Based on Phase Synchronization

The brain active patterns were organized differently under resting states of eyes open (EO) and eyes closed (EC). The altered voxel-wise and regional-wise resting state active patterns under EO/EC were found by static analysis. More importantly, dynamical spontaneous functional connectivity has been observed in the resting brain. To the best of our knowledge, the dynamical mechanisms of intrinsic connectivity networks (ICNs) under EO/EC remain largely unexplored. The goals of this paper were twofold: 1) investigating the dynamical intra-ICN and inter-ICN temporal patterns during resting state; 2) analyzing the altered dynamical temporal patterns of ICNs under EO/EC. To this end, a cohort of healthy subjects with scan conditions of EO/EC were recruited from 1000 Functional Connectomes Project. Through Hilbert transform, time-varying phase synchronization (PS) was applied to evaluate the inter-ICN synchrony. Meanwhile, time-varying amplitude was analyzed as dynamical intra-ICN temporal patterns. The results found six micro-states of inter-ICN synchrony. The medial visual network (MVN) showed decreased intra-ICN amplitude during EC relative to EO. The sensory-motor network (SMN) and auditory network (AN) exhibited enhanced intra-ICN amplitude during EC relative to EO. Altered inter-ICN PS was found between certain ICNs. Particularly, the SMN and AN exhibited enhanced PS to other ICNs during EC relative to EO. In addition, the intra-ICN amplitude might influence the inter-ICN synchrony. Moreover, default mode network (DMN) might play an important role in information processing during EO/EC. Together, the dynamical temporal patterns within and between ICNs were altered during different scan conditions of EO/EC. Overall, the dynamical intra-ICN and inter-ICN temporal patterns could benefit resting state fMRI-related research, and could be potential biomarkers for human functional connectome.     

Dihydroxylphenyl amides as inhibitors of the Hsp90 molecular chaperone

Information from X-ray crystal structures were used to optimize the potency of a HTS hit in a Hsp90 competitive binding assay. A class of novel and potent small molecule Hsp90 inhibitors were thereby identified. Enantio-pure compounds 31 and 33 were potent in PGA-based competitive binding assay and inhibited proliferation of various human cancer cell lines in vitro, with IC(50) values averaging 20 nM.     

钙调蛋白拮抗剂对人胃癌细胞效应机理的研究——钙调蛋白与磷酸二酯酶活性测定分析*

我们曾经证明钙调蛋白(Calmodulin,CaM)拮抗剂三氟拉嗪(Trifluoperazine,TFP)有抑制人胃癌细胞增殖和诱导细胞形态向正常分化的效应。本文用CaM活性测定箱方法测定了TFP处理的人胃癌MGC-803细胞胞质内的CaM活性。同时也测定了磷酸二酯酶(Phosphodiesterase.PDE)活性的变化。结果表明TFP选择性抑制胞质内依赖Ca~(2+)/CaM的PDE活性。氨茶碱有抑制CaM活化PDE的作用。本文对TFP作用机理及在调控癌细胞增殖及分化中的意义进行讨论。