Bererine induces peripheral lymphocytes immune regulations to realize its neuroprotective effects in the cerebral ischemia/reperfusion mice

Previous studies have shown that Bererine (Ber) has significant neuroprotective effects and the present article aimed to investigate its mechanism from the aspect of peripheral immune system. We evaluated the effects of Ber 24 h after cerebral ischemia/reperfusion (I/R) on histologic injury in BALB/C mice and NOD-SCID (severe combined immunodeficient) mice lacking T and B cells. Infarct volume, neurological scores and brain water content were strikingly reduced by Ber in BALB/C mice versus NOD-SCID mice. Which suggested that Ber induces peripheral immune regulations to realize its neuroprotective effects in the cerebral I/R mice. Then we tested the lymphocytes from BALB/C lymph nodes (LNs) with their survival, activation, proliferation, cell cycle, apoptosis and differentiation induced by cytokine secretion to provide direct evidences that Ber realized its neuroprotective effects by regulating I/R-induced peripheral lymphocytes early immunoactivation and following immunotolerance and to better understand the importance of peripheral immune system following I/R insults.     

A cell surface inactive mutant of the human lutropin receptor (hLHR) attenuates signaling of wild-type or constitutively active receptors via heterodimerization

The D405N and Y546F mutations of the human lutropin receptor (hLHR) have previously been shown to partially attenuate hCG-stimulated cAMP synthesis despite normal cell surface expression and hCG binding affinity (Min, L. and Ascoli, M. Mol. Endocrinol. 14:1797–1810, 2000). We now show that these mutations each stabilize a resting state of the hLHR. A combined mutant D405N,Y546F is similarly expressed at the cell surface and exhibits normal ligand-binding, but is profoundly signaling impaired. Introduction of hLHR(wt) into cells stably expressing the signaling inactive D405N,Y546F resulted in the attenuation of hCG-stimulated cAMP production by hLHR(wt) even if excess Gs is co-expressed. Similarly, co-expression of D405N,Y546F with hLHR constitutively active mutants (CAMs) attenuated their constitutive activity. Quantitative bioluminescence resonance energy transfer (BRET) analyses demonstrated that D405N,Y546F formed heterodimers with both wt and CAM hLHR. In contrast hLHR(D405N,Y546F) did not heterodimerize with the melanocortin 3 receptor (MC3R) and agonist-stimulated cAMP production through the MC3R was not attenuated when these two receptors were co-expressed. Taken altogether, our data demonstrate that a signaling inactive hLHR mutant (that is trafficked normally to the plasma membrane) attenuates the signaling of the cell surface localized wt or the constitutively active hLHR due to receptor heterodimerization. Our studies, therefore, suggest a novel ramification of GPCR signaling resulting from receptor dimerization.     

Genome-wide investigation on the genetic variations of rice disease resistance genes

Exploitation of plant disease resistance (R) gene in breeding programs has been proven to be the most efficient strategy for coping with the threat of pathogens. An understanding of R-gene variation is the basis for this strategy. Here we report a genome-wide investigation on the variation of NBS-LRR-encoding genes, the common type of R genes, between two sequenced rice genomes, Oryza sativa L. var. Nipponbare and 93–11. We show that the allelic nucleotide diversity in 65.0% of 397 least-divergent pairs is not high (0.344% on average), while the remaining 35% display a greater diversity (5.4% on average). The majority of conserved R genes is single-copy and/or located as a singleton. The clustered, particularly the complex-clustered, R-genes contribute greatly to the rich genetic variation. Surprisingly only 11.2% of R-genes have remarkably high ratios of non-synonymous to synonymous rates, which is much less than the 17.4% observed between Arabidopsis genomes. Noticeable “artificially selective sweeping” could be detected in a large proportion of the conserved R-genes, a scenario described in the “arms race” co-evolutionary model. Based on our study, a variation pattern of R-genes is proposed and confirmed by the analysis of R-genes from other rice lines, indicating that the observed variation pattern may be common in all rice lines.Electronic Supplementary Material Supplementary material is available for this article at     

神经生长锥内α-spectrin与F-actin的免疫细胞化学研究

目的 为了探讨α血影蛋白（α-spectrin）和纤维型肌动蛋白（F-actin)在神经生长锥激烈运动与神经生长过程中的作用机制。方法 采用免疫双荧光染色法,以共聚焦激光扫描显微镜观察初代培养脊神经节细胞生长锥的连续水平断面上观察α-spectrin和F-actin的三维分布特点及其相互关系。结果 在水平面上,α-spectrin和F-actin分布在细胞质中,尤以细胞膜下,生长锥的P区伸展方向的前端和丝状伪足内分布最多,且α-spectrin比Factin更接近细胞膜,在纵轴方向,α-spectrin从基质侧到表达游离侧都有分布,而F-actin在生长锥体部C区和表面游离侧分布较少。结论 提示 F-actin共同参与生长锥运动,神经生长外,还参与构筑生长锥内的三维网架及维持生长锥的极性。     

下辽河平原农业生态系统不同施肥制度的土壤养分收支

本试验是在潮棕壤上进行了10年的定位试验,研究了在养分循环再利用的基础上采取不同施肥制度下作物养分移出量,并结合施肥量计算出土壤中N,P,K养分收支。结果表明,在保持农业系统养分循环再利用的基础上,根据养分供给力设计化肥施用量,不仅可实现作物主产,而且可平衡土壤养分收支,避免土壤中肥料养分过剩（主要是N）进入环境,并揭示了我国我国在20世纪70年代以前大面积农田土壤缺P和80年代农田土壤大面积缺K的原因。     

臭氧对微生物杀菌作用的初步研究

以稀释平板计数法 ,测定了臭氧对水体和空气环境的消毒杀菌作用。结果表明 :随着臭氧浓度 (时间 )的增加 ,对各类微生物杀灭率明显上升 ,除了芽孢杆菌外 ,杀灭率可以达到 1 0 0 %。     

光合细菌利用工业有机废水产生5-氨基乙酰丙酸

[目的]利用本实验室筛选的5-氨基乙酰丙酸(5-aminolevulinic acid,ALA)高产紫色非硫红假单胞菌株,以味精、柠檬酸、啤酒和豆制品生产废水作为底物,进行光合细菌利用废水产生ALA并去除化学需氧量(CODcr)的研究.[方法]光合细菌培养温度为30℃,光照强度为3000 Lux,进行乙酰丙酸、甘氨酸、琥珀酸的添加与否和废水灭菌与否的处理,用比色法测定菌液光密度,ALA检测采用Ehrlich'S试剂分光光度检测法.[结果]在不添加乙酰丙酸(levulinic acid,LA)、甘氨酸和琥珀酸的条件下,菌株99-28的菌体生长在72～96 h达到稳定期,ALA产量在96h最高,在4种废水中,味精废水的ALA产量最高,CODcr去除率也最高;添加LA、甘氨酸和琥珀酸显著提高ALA产量,但CODcr去除效果不好.废水不灭菌略微降低99-28菌株的生长和CODcr的去除能力,在添加LA、甘氨酸和琥珀酸的条件下的,ALA产量明显下降.ALA高产突变菌株L-1在有机废水中的生长状况、对有机废水的CODcr去除与菌株99-28表现一致,在不添加和添加LA、甘氨酸和琥珀酸的条件下,突变株L-1的ALA产量明显比菌株99-28高.[结论]本实验室筛选的紫色非硫红假单胞菌株能利用有机废水作为底物产生ALA并降解CODcr.     

The N- and C-terminal domains of the NS1 protein of influenza B virus can independently inhibit IRF-3 and beta interferon promoter activation

The NS1 proteins of influenza A and B viruses (A/NS1 and B/NS1 proteins) have only approximately 20% amino acid sequence identity. Nevertheless, these proteins show several functional similarities, such as their ability to bind to the same RNA targets and to inhibit the activation of protein kinase R in vitro. A critical function of the A/NS1 protein is the inhibition of synthesis of alpha/beta interferon (IFN-alpha/beta) during viral infection. Recently, it was also found that the B/NS1 protein inhibits IFN-alpha/beta synthesis in virus-infected cells. We have now found that the expression of the B/NS1 protein complements the growth of an influenza A virus with A/NS1 deleted. Expression of the full-length B/NS1 protein (281 amino acids), as well as either its N-terminal RNA-binding domain (amino acids 1 to 93) or C-terminal domain (amino acids 94 to 281), in the absence of any other influenza B virus proteins resulted in the inhibition of IRF-3 nuclear translocation and IFN-beta promoter activation. A mutational analysis of the truncated B/NS1(1-93) protein showed that RNA-binding activity correlated with IFN-beta promoter inhibition. In addition, a recombinant influenza B virus with NS1 deleted induces higher levels of IRF-3 activation, as determined by its nuclear translocation, and of IFN-alpha/beta synthesis than wild-type influenza B virus. Our results support the hypothesis that the NS1 protein of influenza B virus plays an important role in antagonizing the IRF-3- and IFN-induced antiviral host responses to virus infection.     

Functional replacement of the carboxy-terminal two-thirds of the influenza A virus NS1 protein with short heterologous dimerization domains

The NS1 protein of influenza A/WSN/33 virus is a 230-amino-acid-long protein which functions as an interferon alpha/beta (IFN-alpha/beta) antagonist by preventing the synthesis of IFN during viral infection. In tissue culture, the IFN inhibitory function of the NS1 protein has been mapped to the RNA binding domain, the first 73 amino acids. Nevertheless, influenza viruses expressing carboxy-terminally truncated NS1 proteins are attenuated in mice. Dimerization of the NS1 protein has previously been shown to be essential for its RNA binding activity. We have explored the ability of heterologous dimerization domains to functionally substitute in vivo for the carboxy-terminal domains of the NS1 protein. Recombinant influenza viruses were generated that expressed truncated NS1 proteins of 126 amino acids, fused to 28 or 24 amino acids derived from the dimerization domains of either the Saccharomyces cerevisiae PUT3 or the Drosophila melanogaster Ncd (DmNcd) proteins. These viruses regained virulence and lethality in mice. Moreover, a recombinant influenza virus expressing only the first 73 amino acids of the NS1 protein was able to replicate in mice lacking three IFN-regulated antiviral enzymes, PKR, RNaseL, and Mx, but not in wild-type (Mx-deficient) mice, suggesting that the attenuation was mainly due to an inability to inhibit the IFN system. Remarkably, a virus with an NS1 truncated at amino acid 73 but fused to the dimerization domain of DmNcd replicated and was also highly pathogenic in wild-type mice. These results suggest that the main biological function of the carboxy-terminal region of the NS1 protein of influenza A virus is the enhancement of its IFN antagonist properties by stabilizing the NS1 dimeric structure.