螺旋粉虱对不同波长发光二极管的趋光反应

螺旋粉虱Aleurodicus disperses Russell是很多果树和观赏植物的重要害虫.本文应用六角体装置研究了螺旋粉虱成虫对6种波长发光二极管(LED)的趋性反应,这些LED分别为:紫(405 nm);蓝(461 nm);绿(519 nm);黄(570 nm);红(650 nm)和红外(850 nm).结果表明紫光LED(405 nm)对螺旋粉虱的吸引率显著高于其它波长的LED,两性间没有显著的差异.短波长较长波长的可见光对螺旋粉虱更具吸引力.研究结果可为提高灯诱对螺旋粉虱的吸引率提供依据.     

皮质抑素的生物学效应研究进展

皮质抑素是1996年在哺乳动物大脑皮质中发现的与生长抑素结构有高度同源性的活性多肽,广泛分布于人体的组织器官中,包括大脑皮质、冠状动脉、胃、肾、睾丸、视网膜、白细胞和免疫系统等.研究表明,皮质抑素能够与生长抑素受体、生长激素促分泌物受体1a及Mas相关基因2受体结合发挥多种生物学作用,包括调节学习与记忆过程,诱导睡眠,抑制炎症,调节内分泌代谢及发挥心血管效应,是调节机体自稳态平衡的重要因素.     

短柄禾叶蕨配子体发育的研究

首次通过人工培养的方式,详细记录了短柄禾叶蕨（Grammitis dorsipila (Christ.)C.Chr.）具代表性的配子体形态发育全过程及各环节的特征,包括孢子萌发、原丝体、毛状体、叶绿体、边缘细胞、精子器等,并附特征性结构照片29幅。为禾叶蕨科（Grammitidaceae）的研究积累了配子体发育方面的详实资料,并初步讨论了短柄禾叶蕨配子体特征所体现的系统学意义。     

Physical mapping of DNA markers linked to stem rust resistance gene <Emphasis Type="Italic">Sr47</Emphasis> in durum wheat

Key message

Markers linked to stem rust resistance gene Sr47 were physically mapped in three small Aegilops speltoides chromosomal bins. Five markers, including two PCR-based SNP markers, were validated for marker-assisted selection.

Abstract

In durum wheat (Triticum turgidum subsp. durum), the gene Sr47 derived from Aegilops speltoides conditions resistance to race TTKSK (Ug99) of the stem rust pathogen (Puccinia graminis f. sp. tritici). Sr47 is carried on small interstitial translocation chromosomes (Ti2BL-2SL-2BL·2BS) in which the Ae. speltoides chromosome 2S segments are divided into four bins in genetic stocks RWG35, RWG36, and RWG37. Our objective was to physically map molecular markers to bins and to determine if any of the molecular markers would be useful in marker-assisted selection (MAS). Durum cultivar Joppa was used as the recurrent parent to produce three BC₂F₂ populations. Each BC₂F₂ plant was genotyped with markers to detect the segment carrying Sr47, and stem rust testing of BC₂F₃ progeny with race TTKSK confirmed the genotyping. Forty-nine markers from published sources, four new SSR markers, and five new STARP (semi-thermal asymmetric reverse PCR) markers, were evaluated in BC₂F₂ populations for assignment of markers to bins. Sr47 was mapped to bin 3 along with 13 markers. No markers were assigned to bin 1; however, 7 and 13 markers were assigned to bins 2 and 4, respectively. Markers Xrwgs38a, Xmag1729, Xwmc41, Xtnac3119, Xrwgsnp1, and Xrwgsnp4 were found to be useful for MAS of Sr47. However, STARP markers Xrwgsnp1 and Xrwgsnp4 can be used in gel-free systems, and are the preferred markers for high-throughput MAS. The physical mapping data from this study will also be useful for pyramiding Sr47 with other Sr genes on chromosome 2B.

     

Familial Correlations of Onset Age of Hepatocellular Carcinoma: A Population-Based Case-Control Family Study

Background

There was lack of evidence for familial aggregation in onset age of hepatocellular carcinoma (HCC) in Chinese population. We conducted a population-based case-control family study to examine familial correlation of age of HCC onset in Taixing, China.

Methods

A total of 202 cases and 202 matched controls as well as their relatives were included in the study. Lifetime cumulative risks of HCC were estimated using the Kaplan-Meier approach. Cross ratios (CRs) were obtained from stratified Cox proportional hazard models, to assess the familial correlation of onset age.

Results

The mean age of HCC onset was decreased as increasing number of HCC cases in a family. The onset age was the earliest for first-degree relatives, intermediate for second-degree relatives, and latest for non-blood relatives (spouse) (log-rank test, P<0.01). The onset age was significantly correlated between probands and their relatives. In stratified Cox proportional hazard models, the CRs for the probands versus their fathers, mothers, siblings and uncles/aunts were 6.25 (95% confidence interval (CI): 1.84–21.25), 9.81 (95% CI: 1.24–77.56), 6.22 (95% CI: 1.37–28.36) and 3.24 (95% CI: 1.26–8.33), respectively. After adjustment for hepatitis B virus infection, the CRs remained significant.

Conclusion

This current study suggested a significant correlation of onset age for HCC among blood relatives. Familial HCC cases yielded earlier age of onset and their relatives have higher HCC risk in early age, highlighting intensive surveillance should be start at an earlier age for individuals with family history of HCC.     

Mitochondrial genomes suggest that hexapods and crustaceans are mutually paraphyletic

For over a century the relationships between the four major groups of the phylum Arthropoda (Chelicerata, Crustacea, Hexapoda and Myriapoda) have been debated. Recent molecular evidence has confirmed a close relationship between the Crustacea and the Hexapoda, and has included the suggestion of a paraphyletic Hexapoda. To test this hypothesis we have sequenced the complete or near-complete mitochondrial genomes of three crustaceans (Parhyale hawaiensis, Squilla mantis and Triops longicaudatus), two collembolans (Onychiurus orientalis and Podura aquatica) and the insect Thermobia domestica. We observed rearrangement of transfer RNA genes only in O. orientalis, P. aquatica and P. hawaiensis. Of these, only the rearrangement in O. orientalis, an apparent autapomorphy for the collembolan family Onychiuridae, was phylogenetically informative.We aligned the nuclear and amino acid sequences from the mitochondrial protein-encoding genes of these taxa with their homologues from other arthropod taxa for phylogenetic analysis. Our dataset contains many more Crustacea than previous molecular phylogenetic analyses of the arthropods. Neighbour-joining, maximum-likelihood and Bayesian posterior probabilities all suggest that crustaceans and hexapods are mutually paraphyletic. A crustacean clade of Malacostraca and Branchiopoda emerges as sister to the Insecta sensu stricto and the Collembola group with the maxillopod crustaceans. Some, but not all, analyses strongly support this mutual paraphyly but statistical tests do not reject the null hypotheses of a monophyletic Hexapoda or a monophyletic Crustacea. The dual monophyly of the Hexapoda and Crustacea has rarely been questioned in recent years but the idea of both groups' paraphyly dates back to the nineteenth century. We suggest that the mutual paraphyly of both groups should seriously be considered.     

F0F1-ATPase as biosensor to detect single virus

F(0)F(1)-ATPase within chromatophore was constructed as a biosensor (immuno-rotary biosensor) for the purpose of capturing single virus. Capture of virus was based on antibody-antigen reaction. The detection of virus based on proton flux change driven by ATP-synthesis of F(0)F(1)-ATPase, which was indicated by F1300, was directly observed by a fluorescence microscope. The results demonstrate that the biosensor loading of virus particles has remarkable signal-to-noise ratio (3.8:1) compared to its control at single molecular level, and will be convenient, quick, and even super-sensitive for detecting virus particles.     

双歧杆菌脂磷壁酸与5-氟尿嘧啶联用的抗肿瘤研究

目的探讨双歧杆菌脂磷壁酸与5-氟尿嘧啶（5-Fu）联用对H22荷瘤小鼠的抗肿瘤作用及免疫功能的影响。方法双歧杆菌脂磷壁酸单独或联合5-Fu处理H22荷瘤Balb／c小鼠,定期测量肿瘤大小,观察小鼠一般状况;计算抑瘤率、血红细胞数和白细胞数,取脾和胸腺计算脏器指数;HE染色分析肿瘤组织变化;MTT法检测小鼠脾T淋巴细胞增殖转化功能以及ELISA法检测小鼠脾淋巴细胞分泌IFN-γ含量。结果双歧杆菌脂磷壁酸及5-Fu单独应用均可抑制肿瘤生长,但单独5-Fu处理组小鼠一般状况差,毒性反应重;双歧杆菌脂磷壁酸与5-Fu联合应用,与单独5-Fu处理组比较,不仅抑瘤率明显提高（P〈0．01）,且荷瘤小鼠一般状况改善,白细胞数升高,脏器指数增加,小鼠脾T淋巴细胞增殖能力强,脾淋巴细胞分泌IFN-γ,水平提高;光镜观察HE染色瘤体组织,双歧杆菌脂磷壁酸处理组可见大量炎症细胞浸润。结论双歧杆菌脂磷壁酸联合5-FU能增强化疗的抑瘤作用,并能扭转化疗引起的免疫低下现象,起到增效减毒作用。     

Quercetin Protects against Okadaic Acid-Induced Injury via MAPK and PI3K/Akt/GSK3β Signaling Pathways in HT22 Hippocampal Neurons

Increasing evidence shows that oxidative stress and the hyperphosphorylation of tau protein play essential roles in the progression of Alzheimer’s disease (AD). Quercetin is a major flavonoid that has anti-oxidant, anti-cancer and anti-inflammatory properties. We investigated the neuroprotective effects of quercetin to HT22 cells (a cell line from mouse hippocampal neurons). We found that Okadaic acid (OA) induced the hyperphosphorylation of tau protein at Ser199, Ser396, Thr205, and Thr231 and produced oxidative stress to the HT22 cells. The oxidative stress suppressed the cell viability and decreased the levels of lactate dehydrogenase (LDH), superoxide dismutase (SOD), mitochondria membrane potential (MMP) and Glutathione peroxidase (GSH-Px). It up-regulated malondialdehyde (MDA) production and intracellular reactive oxygen species (ROS). In addition, phosphoinositide 3 kinase/protein kinase B/Glycogen synthase kinase3β (PI3K/Akt/GSK3β) and mitogen activated protein kinase (MAPK) were also involved in this process. We found that pre-treatment with quercetin can inhibited OA-induced the hyperphosphorylation of tau protein and oxidative stress. Moreover, pre-treatment with quercetin not only inhibited OA-induced apoptosis via the reduction of Bax, and up-regulation of cleaved caspase 3, but also via the inhibition of PI3K/Akt/GSK3β, MAPKs and activation of NF-κB p65. Our findings suggest the therapeutic potential of quercetin to treat AD.     

A new Illumina MiSeq high-throughput sequencing-based method for evaluating the composition of the Bacteroides community in the intestine using the rpsD gene sequence

Bacteroides is a bacterial genus that is known to closely interact with the host. The potential role of this genus is associated with its ecological status and distribution in the intestine. However, the current 16S V3–V4 region sequencing method can only detect the abundance of this genus, revealing a need for a novel sequencing method that can elucidate the composition of Bacteroides in the human gut microbiota. In this study, a core gene, rpsD, was selected as a template for the design of a Bacteroides-specific primer set. We used this primer set to develop a novel assay based on the Illumina MiSeq sequencing platform that enabled an accurate assessment of the Bacteroides compositions in complex samples. Known amounts of genomic DNA from 10 Bacteroides species were mixed with a complex sample and used to evaluate the performance and detection limit of our assay. The results were highly consistent with those of direct sequencing with a low Bacteroides DNA detection threshold (0.01 ng), supporting the reliability of our assay. In addition, the assay could detect all the known Bacteroides species within the faecal sample. In summary, we provide a sensitive and specific approach to determining the Bacteroides species in complex samples.