湖南省长沙市某屠宰场猪群主要疫病检测

为了解湖南省临床健康猪群主要疫病流行情况,2017年从长沙市某屠宰场采集猪组织样品390份,应用实时荧光定量PCR方法,检测猪瘟病毒(CSFV)、猪繁殖与呼吸综合征病毒(PRRSV)、猪伪狂犬病病毒(PRV)、猪圆环病毒2型(PCV2)、高致病性猪繁殖与呼吸综合征病毒(HPPRRSV)和口蹄疫病毒(FMDV)。结果显示,这6种病毒的感染率分别为5.13%、23.85%、8.46%、77.95%、24.10%和0.51%。对猪群的混合感染情况进行分析发现:PCV2与其他病原的混合感染率最高;二重感染最高的是"PRV+PCV2",达到7.43%,其次是"PRRSV+PCV2",为2.31%;三重感染率最高的是"HPPRRSV+PRRSV+PCV2",达到11.54%,其次是"CSFV+HPPRRSV+PRRSV",为0.77%;四重感染最高的是"CSFV+HPPRRSV+PRRSV+PCV2",达到3.85%,其次是"HPPRRSV+PRRSV+PRV+PCV2",为0.77%。结果表明:临床健康猪群中的PCV2感染率最高,且常与PRRSV和PRV发生混合感染;加强养殖环节PCV2、PRRSV、HPPRRSV和PRV的监控,对于控制常见猪群疫病具有重要意义。

Gene expression profile in rat small intestinal allografts after cold preservation/reperfusion

AIM: To determine the changes of gene expression profile in small intestinal allografts in rats after cold preservation/ reperfusion, and to identify the genes relevant to cold preservation/reperfusion injury. METHODS: Heterotopic segmental small bowel transplantation was performed in six rats with a sham operation and they were used as controls. Total RNA was extracted from the allografts (experimental group) and normal intestines (control group) 1 h after cold preservation/ reperfusion, and then purified to mRNA, which was then reversely transcribed to cDNA, and labeled with fluorescent Cy5-dUTP and Cy3-dUTP to prepare hybridization probes. The mixed probes were hybridized to the cDNA microarray. After high-stringent washing, the fluorescent signals on cDNA microarray chip were scanned and analyzed. RESULTS: Among the 4 096 target genes, 82 differentially expressed genes were identified between the two groups. There were 18 novel genes, 33 expression sequence tags, and 31 previously reported genes. The selected genes may be divided into four classes: genes modulating cellular adhesion, genes regulating cellular energy, glucose and protein metabolism, early response genes and other genes. CONCLUSION: A total of 82 genes that may be relevant to cold preservation/reperfusion injury in small intestinal allografts are identified. Abnormal adhesion between polymorphonuclears and endothelia and failure in energy, glucose and protein metabolism of the grafts may contribute to preservation/reperfusion injury. The functions of the novel genes identified in our study need to be clarified further.

Geological and Geochemical Characteristics of Early Cretaceous Mafic Dikes in Northern Jiangxi Province, SE China and Their Geodynamic Implications

The development of Early Cretaceous mafic dikes in northern and southern Jiangxi allows an understanding of the geodynamic setting and characteristics of the mantle in southeast China in the Cretaceous. Geological and geochemical characteristics for the mafic dikes from the Wushan copper deposit and No. 640 uranium deposit are given in order to constrain the nature of source mantle, genesis and tectonic implications. According to the mineral composition, the mafic dikes in northern Jiangxi can be divided into spessartite and olive odinite types, which belong to slightly potassium-rich calc-alkaline lamprophyre characterized by enrichment in large ion lithophile elements (LILE) and light rare earth elements (LREE), large depletion in high strength field elements (HSFE) and with negative Nb, Ta and Ti anomalies, as well as 87Sr/86Sr ratios varying from 0.7055 to 0.7095 and 143Nd/144Nd ratios varying from 0.5119 to 0.5122. All features indicate that the magma responsible for the mafic dikes was derived mainly from metasomatic lithosphere mantle related to dehydration and/or upper crust melting during subduction. Differences in geochemical characteristics between the mafic dikes in northern Jiangxi and the Dajishan area, southern Jiangxi were also studied and they are attributed to differences in regional lithospheric mantle components and/or magma emplacement depth. Combining geological and geochemical characteristics with regional geological history, we argue that southeast China was dominated by an extensional tectonic setting in the Early Cretaceous, and the nature of the mantle source area was related to enrichment induced by asthenosphere upwelling and infiltration of upper crust-derived fluids responding to Pacific Plate subduction.

Geochemical characteristics of seamount ferromanganese nodules from mid-Pacific Ocean

Nine seamount ferromanganese nodules from six seamounts in the mid-Paciflc Ocean have been sampled,the obtained sixteen sub-samples were used to analyze their main elements, trace elements and rare earth elements by the chemical method and ICP-MS, platinum group elements have also been analyzed for some subsamples, using the methods of Te co-precipitation pre-concentration and isotope dilution. All subsamples have been analyzed by X-ray diffraction for their mineral composition. It is shown from the analysis results that the mineral composition, chemical characteristics and the occurrence of main components of seamount nodules from mid-Pacific Ocean are similar to those of hydrogenous cobalt-rich crust on seamounts, which indicates that seamount nodules were hydrogenous. Compared with the ferromanganese nodules occurring on the surface of deep-sea sediments, seamount nodules have higher Fe and Co but lower Cu and Ni, so the seamount nodules from mid-Pacific Ocean might be formed on the surface of sediments on seamounts in weak acidic but strong oxidation environment. Because of their similar occurring depth and redox conditions, seamount nodules are very similar to cobait-rich crust in their chemical composition, minerals and occurrence of main compositions. However, having been found on the sediment-seawater interface, seamount nodules experienced the influence of early-diagenesis of sediments, so the typical seamount crust has some characteristics of transition to ferromanganese nodules.