Transcriptional analysis of normal human fibroblast responses to microgravity stress

To understand the molecular mechanism（s） of how spaceflight affects cellular signaling pathways, quiescent normal human WI-38 fibroblasts were flown on the STS-93 space shuttle mission. Subsequently, RNA samples from the spaceflown and ground-control cells were used to construct two cDNA libraries, which were then processed for suppression subtractive hybridization （SSH） to identify spaceflight-specific gene expression. The SSH data show that key genes related to oxidative stress, DNA repair, and fatty acid oxidation are activated by spaceflight, suggesting the induction of cellular oxidative stress. This is further substantiated by the up-regulation of neuregulin 1 and the calcium-binding protein calmodulin 2. Another obvious stress sign is that spaceflight evokes the Ras/mitogen-activated protein kinase and phosphatidylinositol-3 kinase signaling pathways, along with up-regulating several Gl-phase cell cycle traverse genes. Other genes showing upregulation of expression are involved in protein synthesis and pro-apoptosis, as well as pro-survival. Interactome analysis of functionally related genes shows that c-Myc is the ＂hub＂ for those genes showing significant changes. Hence, our results suggest that microgravity travel may impact changes in gene expression mostly associated with cellular stress signaling, directing cells to either apoptotic death or premature senescence.     

Genotypic diversity of Haemophilus parasuis field strains

Haemophilus parasuis is the cause of Gl?sser's disease and other clinical disorders in pigs. It can also be isolated from the upper respiratory tracts of healthy pigs, and isolates can have significant differences in virulence. In this work, a partial sequence from the 60-kDa heat shock protein (Hsp60) gene was assessed as an epidemiological marker. We analyzed partial sequences of hsp60 and 16S rRNA genes from 103 strains of H. parasuis and other related species to obtain a better classification of the strains and examine the correlation with virulence. The results were compared with those obtained by enterobacterial repetitive intergenic consensus PCR. Our results showed that hsp60 is a reliable marker for epidemiological studies of H. parasuis and that the analysis of its sequence is a better approach than fingerprinting methods. Furthermore, the analysis of the hsp60 and 16S rRNA gene sequences revealed the presence of a separate lineage of virulent strains and indicated the occurrence of lateral gene transfer among H. parasuis and Actinobacillus strains.     

Genome sequence of Haemophilus parasuis strain 29755

Haemophilus parasuis is a member of the family Pasteurellaceae and is the etiologic agent of Glässer’s disease in pigs, a systemic syndrome associated with only a subset of isolates. The genetic basis for virulence and systemic spread of particular H. parasuis isolates is currently unknown. Strain 29755 is an invasive isolate that has long been used in the study of Glässer’s disease. Accordingly, the genome sequence of strain 29755 is of considerable importance to investigators endeavoring to understand the molecular pathogenesis of H. parasuis. Here we describe the features of the 2,224,137 bp draft genome sequence of strain 29755 generated from 454-FLX pyrosequencing. These data comprise the first publicly available genome sequence for this bacterium.     

副猪嗜血杆菌毒力因子研究进展

副猪嗜血杆菌(Haemophilus parasuis,HPS)是猪上呼吸道的一种常在菌,但却因其被证明是以多发性浆膜炎、关节炎、呼吸困难、高热及高死亡率为特征的Glasser病的病原体而广受关注。介绍了巴氏杆菌科一些常见的毒力相关蛋白、神经氨酸酶、血清型以及毒力相关的三聚自身转运载体与HPS毒力之间的关系,另外就近年来对HPS毒力因子方面的一些研究报道和成果作一综述。     

副猪嗜血杆菌检测技术研究进展

副猪嗜血杆菌是存在于健康猪上呼吸道的一种致病菌,也是格拉泽氏病的病原,近年来其发生与流行给养猪业造成巨大的经济损失,现已成为危害养猪业较严重的细菌性疾病之一.及时、准确地检测出该病以便采取相应的措施,是成功防制该病的关键.本文就从血清学、病原学、分子生物学等方面阐明了副猪嗜血杆菌的检测技术,从而为兽医临床诊断与治疗提供参考.     

Complete Genome Sequence of Haemophilus parasuis SH0165

Haemophilus parasuis is the causative agent of Glässer's disease, which produces big losses in swine populations worldwide. H. parasuis SH0165, belonging to the dominant serovar 5 in China, is a clinically isolated strain with high-level virulence. Here, we report the first completed genome sequence of this species.     

Transcriptional responses of Arabidopsis thaliana plants to As (V) stress

Background

Plants encode a large number of leucine-rich repeat receptor-like kinases. Legumes encode several LRR-RLK linked to the process of root nodule formation, the ligands of which are unknown. To identify ligands for these receptors, we used a combination of profile hidden Markov models and position-specific iterative BLAST, allowing us to detect new members of the CLV3/ESR (CLE) protein family from publicly available sequence databases.

Results

We identified 114 new members of the CLE protein family from various plant species, as well as five protein sequences containing multiple CLE domains. We were able to cluster the CLE domain proteins into 13 distinct groups based on their pairwise similarities in the primary CLE motif. In addition, we identified secondary motifs that coincide with our sequence clusters. The groupings based on the CLE motifs correlate with known biological functions of CLE signaling peptides and are analogous to groupings based on phylogenetic analysis and ectopic overexpression studies. We tested the biological function of two of the predicted CLE signaling peptides in the legume Medicago truncatula. These peptides inhibit the activity of the root apical and lateral root meristems in a manner consistent with our functional predictions based on other CLE signaling peptides clustering in the same groups.

Conclusion

Our analysis provides an identification and classification of a large number of novel potential CLE signaling peptides. The additional motifs we found could lead to future discovery of recognition sites for processing peptidases as well as predictions for receptor binding specificity.     

副猪嗜血杆菌蜂胶苗的制备及免疫效果试验

目的：以原场副猪嗜血杆菌为制苗菌株,制成自家细菌苗,预防本场猪格拉泽氏病。方法：用从河南济源一自繁自养大型养猪场发病猪分离到的副猪嗜血杆菌进行培养,经甲醛灭活,以蜂胶为佐剂,制成原场副猪嗜血杆菌灭活苗,含菌量为200亿/ml。母猪分别于产前30d和15d各注射4ml/头。仔猪出生后,分别在15、30日龄肌肉注射,1.5ml/头。结果：应用试验证明,该灭活苗保护率达98%。结论：该蜂胶苗安全、可靠,对猪格拉泽氏病有较好的预防作用。     

Loop-mediated isothermal amplification for the rapid detection of Haemophilus parasuis

Haemophilus parasuis infection is of considerable economic importance in the swine industry due to the high costs associated with treatment and loss of animals all over the world. In the present study, loop-mediated isothermal amplification (LAMP) is described for the rapid and specific detection of this species. A primer set derived from the inf B gene of H. parasuis was used to validate the assay using 15 H. parasuis reference strains, 39 clinical isolates, 75 positive samples, and 18 other pathogens. The results indicated that positive reactions were confirmed for all H. parasuis strains and specimens by LAMP after 45 min reaction at 65 °C in a water bath, and no cross-reactivity was observed from other non-H. parasuis strains. The detection limit of the conventional PCR was 25 copies, while that of the LAMP was five copies per tube. Therefore, the sensitivity of LAMP was higher than that of PCR. LAMP is likely to be more suitable as a routine diagnostic tool, especially in clinics without complicated equipment such as thermal cycling machines and electrophoresis apparatus. In these scenarios, the H. parasuis LAMP assay has the potential for field diagnosis.