漆树生物学的研究进展

从生物学方面概述了最近20多年来对漆树研究的主要进展,包括漆树品种和资源,形态解剖,漆汁道的发生和发育以及生漆的产生和贮存过程等,并指出了今后在漆树生物学方面的研究方向.     

黄伞菌丝蛋白质营养价值评价

本文测定了黄伞Pholiotaadiposa菌丝粗蛋白含量和氨基酸组成,采用国际上通用的营养价值评价方法,对其蛋白质的营养价值进行全面评价,并与营养价值较高的白灵侧耳Pleurotusnebrodensis、刺芹侧耳Pleurotuseryngii和金顶侧耳Pleurotrscitrinopileatus进行比较。分析结果表明,黄伞菌丝的必需氨基酸含量最高,占其氨基酸总量的43.9%,蛋白质的氨基酸评分(AAS)、化学评分(CS)、必需氨基酸指数(EAAI)、生物价(BV)、营养指数(NI)和氨基酸比值系数分(SRCAA)分别为92.0、71.3、88.5、84.8、40.4和78.8,六项指标均比参比食用菌高。结果说明黄伞菌丝具有很高的营养价值。     

果寡糖和甘露寡糖对断奶仔猪免疫机能的影响

研究探讨了果寡糖和甘露寡糖对断奶仔猪免疫机能的影响。实验采用随机区组设计法将48头健康、体重一致的35日龄断奶杜洛克仔猪分为4组,每组3次重复,每个重复4头进行为期28天的饲养实验。4个处理组分别为:基础日粮 0.5%果寡糖(FOS组)、基础日粮 0.3%甘露寡糖(MOS组)、基础日粮 0.45%果寡糖 0.25%甘露寡糖(F M组)、基础日粮 75 mg/kg金霉素 40 mg/kg洛克沙生(ABT组)。实验结果表明:(1)寡糖组免疫器官指数较ABT组大(P>0.05)。(2)在断奶后第7天,FOS组(0.32±0.49)、MOS组(0.32±0.04)和F M组(0.32±0.07)均较ABT组(0.20±0.01)显著提高了血清免疫球蛋白A(IgA)的浓度(P<0.05),同时FOS组(3.50±0.49)较ABT组(2.68±0.47)显著提高了IgG浓度(P<0.05);F M组显著提高了断奶后第21天IgG浓度(P<0.05);MOS组显著提高了断奶后第21天IgM浓度(P<0.05)。(3)与ABT组相比,FOS显著提高了断奶后第7天胸腺(21.33±6.03对37.33±4.04)、脾脏(19.67±2.08对30.33±8.73)、淋巴结(24.67±4.16对37.67±2.52)CD4 T淋巴细胞百分数(P<0.05);FOS组(21.33±4.04对32.00±5.29)、MOS组(21.33±4.04对37.33±3.21)、F M组(21.33±4.04对32.00±3.60)显著提高了断奶后第28天胸腺CD4 T淋巴细胞百分数(P<0.05);MOS组(20.67±3.51对29.67±5.51)显著提高了断奶后第7天胸腺CD8 T淋巴细胞百分数;F M组(17.00±1.00对22.67±3.06)显著提高了断奶后第7天脾脏CD8 T淋巴细胞百分数(P<0.05);各寡糖组对断奶后第28天CD4 、CD8 T淋巴细胞百分数影响不显著(P>0.05);ABT组(34.33±5.03)在断奶后第7天较F M组(20.67±6.43)显著提高了淋巴结CD8 T淋巴细胞百分数(P<0.05);在断奶后第7天,FOS组(1.42±0.32)、MOS组(1.52±0.46)、F M组(1.51±0.30)淋巴结CD4 与CD8 比值显著(P<0.05)大于ABT组(0.71±0.03);在断奶后第28天,FOS组(1.36±0.21)和MOS组(1.34±0.16)脾脏CD4 与CD8 比值显著(P=0.01)大于ABT组(0.94±0.29),除此之外,各寡糖组CD4 与CD8 比值较寡糖组大(P>0.05),寡糖组间差异不显著。     

Pb and Cd Bioaccumulations in the Habitat and Preys of Red-Crowned Cranes (Grus japonensis) in Zhalong Wetland, Northeastern China

Pb and Cd concentrations in the habitat and preys of the red-crowned crane (i.e., reed rhizomes and three typical aquatic animal families (Perccottus glehni Dybowski, Carassius auratus Linnaeus, and Viviparidae)) were analyzed to examine the impact of these hazards on red-crowned cranes in northeastern China. Results indicated that Pb and Cd concentrations in the preys of the red-crowned cranes were elevated via food chain. Most of the detected Pb and Cd contents in the sediments were above the natural background level, ranging from 9.85 to 129.72 ppm and 1.23 to 10.63 ppm (dry weight), respectively. Cd geo-accumulation index at all sites were larger than 3, even reached 5.22, suggesting serious pollution in this region. Three common water animal families were detected to contain heavy metals, following the order of increasing concentrations: primary consumers (i.e., Viviparidae and Carassius auratus Linnaeus)?<?secondary consumers (i.e., Perccottus glehni Dybowski). Pb and Cd concentrations in the buffer zone are significantly higher than in the core area and being elevated in the food chain. The molten feathers of the red-crowned cranes showed the highest toxic metal concentrations of Pb (2.09 to 5.81 ppm) and Cd (1.42 to 3.06 ppm) compared with the feces produced by cranes and residual eggshell left by water fowls. Exceptionally high Pb and Cd concentrations in the cranes and their preys were thought to be associated with their habitat.     

Negative Regulation of Interferon-induced Transmembrane Protein 3 by SET7-mediated Lysine Monomethylation

Although lysine methylation is classically known to regulate histone function, its role in modulating antiviral restriction factor activity remains uncharacterized. Interferon-induced transmembrane protein 3 (IFITM3) was found monomethylated on its lysine 88 residue (IFITM3-K88me1) to reduce its antiviral activity, mediated by the lysine methyltransferase SET7. Vesicular stomatitis virus and influenza A virus infection increased IFITM3-K88me1 levels by promoting the interaction between IFITM3 and SET7, suggesting that this pathway could be hijacked to support infection; conversely, IFN-α reduced IFITM3-K88me1 levels. These findings may have important implications in the design of therapeutics targeting protein methylation against infectious diseases.     

榆紫叶甲赤眼蜂基础生物学特性及其实验种群生命表

榆紫叶甲赤眼蜂(Asynacta ambrostomae Liao)是榆紫叶甲卵期重要寄生蜂。在实验条件下对榆紫叶甲赤眼蜂生殖、寿命、性比等生物学特性进行观察研究。结果表明：每粒寄主卵平均出蜂量为2.92头,雌雄比为3.64:1,营两性生殖,孤雌产雄。不同营养条件对寿命有显著影响,其中成虫补充20%蜂蜜水和20%蔗糖水能显著增加雌雄虫寿命。组建了25℃条件下榆紫叶甲赤眼蜂成蜂补充不同营养的实验种群生命表,成虫补充20%蜂蜜水、20%蔗糖水、清水、对照组(不添加任何物质)的净生殖力R₀分别为74.42、65.27、56.77和44.50。可见,成蜂补充营养能提高种群生殖力。研究结果将为榆紫叶甲赤眼蜂的开发利用提供理论依据。     

Simvastatin inhibits the additive activation of ERK1/2 and proliferation of rat vascular smooth muscle cells induced by combined mechanical stress and oxLDL through LOX-1 pathway

Vein grafts interposed into arteries are susceptible to the development of atherosclerosis due to rapid increases in blood pressure. This process is accelerated in patients with hyperlipidemia. The molecular mechanism underlying this process is unknown. In this study, quiescent rat vascular smooth muscle cells (VSMCs) were treated in vitro with mechanical stretch stress (10% elongation) with and without oxLDL (25 μg/ml) in the presence and absence of simvastatin (2.5 μmol/L). The results demonstrate that stretch stress and oxLDL can each induce activation of ERK1/2 and Ki-67 expression in VSMCs, but the peak levels of ERK activation and Ki-67 expression were observed in groups subjected to both stretch stress and oxLDL. Simvastatin was found to inhibit increased ERK activation and Ki-67 expression in VSMCs subjected to stretch stress with or without oxLDL. Mechanically, simvastatin was also found to inhibit increased expression of LOX-1 (a receptor of oxLDL) in VSMCs subjected to stretch stress with or without oxLDL. Knockdown of LOX-1 via small interfering RNAs (siRNA-LOX-1) resulted in obvious inhibition of ERK activation in VSMCs subjected to stretch stress with and without oxLDL. These results suggest that combined stretch stress and oxLDL can additively promote the activation of ERK1/2 leading to accelerated proliferation of VSMCs (e.g. increased Ki-67 expression) via LOX-1 signal pathway. This was found to be partially inhibited by simvastatin. These results may provide important data for the treatment and prevention of hypertension with or without hyperlipidemia.     

Mx1‐Cre mediated Rgs12 conditional knockout mice exhibit increased bone mass phenotype

Regulators of G‐protein Signaling (Rgs) proteins are the members of a multigene family of GTPase‐accelerating proteins (GAP) for the Galpha subunit of heterotrimeric G‐proteins. Rgs proteins play critical roles in the regulation of G protein couple receptor (GPCR) signaling in normal physiology and human diseases such as cancer, heart diseases, and inflammation. Rgs12 is the largest protein of the Rgs protein family. Some in vitro studies have demonstrated that Rgs12 plays a critical role in regulating cell differentiation and migration; however its function and mechanism in vivo is largely unknown. Here, we generated a floxed Rgs12 allele (Rgs12^flox/flox) in which the exon 2, containing both PDZ and PTB_PID domains of Rgs12, was flanked with two loxp sites. By using the inducible Mx1‐cre and Poly I:C system to specifically delete Rgs12 at postnatal 10 days in interferon‐responsive cells including monocyte and macrophage cells, we found that Rgs12 mutant mice had growth retardation with the phenotype of increased bone mass. We further found that deletion of Rgs12 reduced osteoclast numbers and had no significant effect on osteoblast formation. Thus, Rgs12^flox/flox conditional mice provide a valuable tool for in vivo analysis of Rgs12 function and mechanism through time‐ and cell‐specific deletion of Rgs12. genesis 51:201–209, 2013. © 2013 Wiley Periodicals, Inc.     

回收乙醇微生物限度检查方法的建立

目的 建立回收乙醇微生物限度检查方法,并对该法的适用性进行确认。方法 探索合适的稀释度来消除乙醇对微生物的抑菌性,寻找合适的过滤量,确定操作步骤。通过多次试验结果确定质量标准。另取3批回收乙醇,进行微生物限度方法适用性试验,分别计算金黄色葡萄球菌( Staphylococcus aureus )、铜绿假单胞菌( Pseudomonas aeruginosa )、枯草芽孢杆菌( Bacillus subtilis )、白色念珠菌( Candida albicans )、黑曲霉( Aspergillus niger )回收率。结果 回收乙醇至少稀释10倍时,可消除其抑菌性。最终确定试验时先用pH 7.0无菌氯化钠-蛋白胨缓冲液将供试品稀释10倍,薄膜过滤法过滤量为每张滤膜100 mL。根据多次微生物限度检查结果,最终确定回收乙醇微生物限度质量标准为不高于10 cfu/mL。方法适用性试验中,3批回收乙醇,5种菌的回收率均在50%~200%范围内,表明该方法适用于回收乙醇的微生物限度检查。结论 回收乙醇经10倍稀释后,可以消除其抑菌性,可以采用薄膜过滤法进行微生物限度检查。