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991.
Gang Wang Bing Han Haoxin Zhou Linfeng Wu Yongwei Wang Guang Jia Jiachen Lv Zhuoxin Cheng Shangha Pan Ji Liu Yinan Zhou Bei Sun 《Apoptosis : an international journal on programmed cell death》2013,18(1):28-42
We aimed to investigate the relationship between the synthesis of hydrogen sulfide (H2S) and the pancreatic acinar cell apoptosis in severe acute pancreatitis (SAP) rats, as well as analyse the potential apoptotic pathway involved in this process. Sixty rats had been equally divided into four groups: sham, SAP, SAP + sodium hydrosulfide (NaHS) and SAP + DL-propargylglycine (PAG). 24 h after SAP induction, all surviving animals of each group were sacrificed to collect blood and tissue samples for the following measurements: the level of serum H2S as well as the levels of tumor necrosis factor-alpha (TNF-α), interleukin-10 (IL-10), H2S synthesizing activity, CSE mRNA and protein expression, maleic dialdehyde (MDA) and myeloperoxidase (MPO) activity, the expression of Bax, Bcl-2, caspase-3, -8 and -9, the release of cytochrome c and the activation of nuclear factor-kappa B (NF-κB), ERK1/2, JNK1/2 and p38 in pancreas. Furthermore, in situ detection of cell apoptosis was examined and the severity of pancreatic damage was analyzed by pathological grading and scoring. Results Significant differences in every index except IL-10 had been found between the SAP, NaHS and PAG groups (P < 0.05). Treatment with PAG obviously induced the pancreatic acinar cell apoptosis as well as improved all the pathological changes and inflammatory parameters. In contrast, administration of NaHS significantly attenuated apoptosis in the pancreas and aggravated the severity of pancreatic damage. Moreover, the expressions of caspase-3, -8, -9 and the release of cytochrome c were all increased in the apoptotic cells, and the activity of NF-κB as well as the phosphorylation of ERK1/2, JNK1/2 and p38 decreased accompanying with the reduction of the serum H2S level. H2S plays a pivotal role in the regulation of pancreatic acinar cell apoptosis in SAP rats. The present results showed that inhibition of H2S synthesis provided protection for SAP rats via inducing acinar cell apoptosis. This process acted through both extrinsic and intrinsic apoptotic pathways, and may be regulated by reducing the activity of NF-κB. 相似文献
992.
Virtualization is widely used in cloud computing environments to efficiently manage resources, but it also raises several challenges. One of them is the fairness issue of resource allocation among virtual machines. Traditional virtualized resource allocation approaches distribute physical resources equally without taking into account the actual workload of each virtual machine and thus often leads to wasting. In this paper, we propose a virtualized resource auction and allocation model (VRAA) based on incentive and penalty to correct this wasting problem. In our approach, we use Nash equilibrium of cooperative games to fairly allocate resources among multiple virtual machines to maximize revenue of the system. To illustrate the effectiveness of the proposed approach, we then apply the basic laws of auction gaming to investigate how CPU allocation and contention can affect applications’ performance (i.e., response time), and its effect on CPU utilization. We find that in our VRAA model, the fairness index is high, and the resource allocation is closely proportional to the actual workloads of the virtual machines, so the wasting of resources is reduced. Experiment results show that our model is general, and can be applied to other virtualized non-CPU resources. 相似文献
993.
Jian Wan Jianliang Zhang Li Zhou Yicheng Wang Congfeng Jiang Yongjian Ren Jue Wang 《Cluster computing》2013,16(4):625-638
Taking advantage of distributed storage technology and virtualization technology, cloud storage systems provide virtual machine clients customizable storage service. They can be divided into two types: distributed file system and block level storage system. There are two disadvantages in existing block level storage system: Firstly, Some of them are tightly coupled with their cloud computing environments. As a result, it’s hard to extend them to support other cloud computing platforms; Secondly, The bottleneck of volume server seriously affects the performance and reliability of the whole system. In this paper we present a lightweighted block-level storage system for clouds—ORTHRUS, based on virtualization technology. We first design the architecture with multiple volume servers and its workflows, which can improve system performance and avoid the problem. Secondly, we propose a Listen-Detect-Switch mechanism for ORTHRUS to deal with contingent volume servers’ failure. At last we design a strategy that dynamically balances load between multiple volume servers. We characterize machine capability and load quantity with black box model, and implement the dynamic load balance strategy which is based on genetic algorithm. Extensive experimental results show that the aggregated I/O throughputs of ORTHRUS are significantly improved (approximately two times of that in Orthrus), and both I/O throughputs and IOPS are also remarkably improved (about 1.8 and 1.2 times, respectively) by our dynamic load balance strategy. 相似文献
994.
Jin-E Zhang Dan Luo Rong-Yi Chen Yan-Ping Yang Ying Zhou Yi-Ming Fan 《Experimental Animals》2013,62(3):205-210
Qualitative measurement of the infective level is relatively difficult in experimental
vaginal candidiasis. Female BALB/c mice aged 8 to 10 weeks were randomly divided into E1,
E2 and E0 groups, which received subcutaneous injection of 0.05 mg, 0.1 mg of estradiol
benzoate or 0.1 ml soybean oil 3 days before vaginal inoculation, respectively, and
hormone treatment continued every other day thereafter. Each group was further divided
into infected and noninfected subgroups. The infected mice were inoculated intravaginally
with 10 µl (5 × 104 conidia) of Candida
albicans suspension, while the noninfected mice were inoculated with 10
µl phosphate-buffered saline. Direct microscopic examination, colony
count and vaginal histopathology including infection degree and inflammation extent were
performed at 3, 7 and 14 days post inoculation. Estrogen treatment increased the vaginal
fungal burden and extent of infection and inflammation compared with the control group,
and 0.3 mg/week estrogen generally induced more severe infection and inflammation than
0.15 mg/week estrogen did. Colony count peaked on day 3 and decreased remarkably after 7
days. Infection score increased gradually during the first 7 days and decreased on day 14,
while inflammation extent exacerbated progressively over the course of 14 days. This study
demonstrates that the modified histological scoring system might be more feasible than
colony count for evaluation of infectivity and dynamic change in experimental vaginal
candidiasis. 相似文献
995.
Yuan Yuan Zhang Jun Hong Liu Yuan ming Zhou Yu Yan Zhang Ying Liu Ting Yun Gong Jing Wang 《Process Biochemistry》2013,48(8):1119-1125
A new two-phase kinetic model of sporulation of Clonostachys rosea in a new solid-state fermentation (SSF) reactor was proposed. The model including exponential and logistic models was applied to study the simultaneous effect of temperature, initial moisture content, medium thickness and surface porosity of the plastic membrane on C. rosea sporulation. The model fits experimental data very well and allows accurate predictions of spore production. The maximum spore production achieved 3.360 × 1010 (spores/gDM), about 10 times greater than that in traditional SSF reactor(data not shown). The new reactor can provide two times sporulation surface area. Moisture content can be adjusted by changing the surface porosity to meet the spore production. Two mixings carried out during fermentation makes medium loose and results in a mass of new sporulation surface area. Therefore, the new SSF reactor would have great potential for application in bulk spore production of fungal biocontrol agents. 相似文献
996.
Miao Bian Irene Waters Sue Broughton Xiao-Qi Zhang Meixue Zhou Reg Lance Dongfa Sun Chengdao Li 《Molecular breeding : new strategies in plant improvement》2013,32(1):155-164
Acid soil/aluminium toxicity is one of the major constraints on barley production around the world. Genetic improvement is the best solution and molecular-marker-assisted selection has proved to be an efficient tool for developing barley cultivars with acid soil/aluminium tolerance. In this study, barley variety Svanhals—introduced from CYMMIT (International Maize and Wheat Improvement Center)—was identified as acid soil/aluminium tolerant and the tolerance was mapped to chromosome 4H in 119 doubled haploid (DH) lines from a cross of Hamelin/Svanhals. The HvMATE gene, encoding an aluminium-activated citrate transporter, was selected as a candidate gene and gene-specific molecular markers were developed to detect acid soil/aluminium tolerance based on the polymerase chain reaction. Sequence analysis of the HvMATE gene identified a 21-bp indel (insertion–deletion) between the tolerant and sensitive cultivars. The new marker was further mapped to the QTL (quantitative trait loci) region on chromosome 4H for acid soil tolerance and accounted for 66.9 % of phenotypic variation in the DH population. Furthermore, the polymorphism was confirmed in other tolerant varieties which have been widely used as a source of acid soil tolerance in Australian barley breeding programs. The new gene-specific molecular marker provides an effective and simple molecular tool for selecting the acid soil tolerance gene from multiple tolerance sources. 相似文献
997.
Yanhong Zhao Peng Chen Xiaofang Liao Bujin Zhou Jian Liao Zhipeng Huang Xiangjun Kong Ruiyang Zhou 《Molecular breeding : new strategies in plant improvement》2013,32(4):969-976
mtDNA was isolated from cytoplasmic male sterility (CMS) line P3A and its maintainer P3B of kenaf (Hibiscus cannabinus L.). The atp9 gene and its two flanking sequences were obtained using homology cloning and high-efficiency thermal asymmetric interlaced PCR methods. The coding sequences showed only two base pairs difference between the CMS and its maintainer, and shared a homology of over 87 % with atp9 genes from other species in GenBank. However, when comparing the flanking sequences, a 47-bp deletion was characterized at the 3′ flanking sequence of atp9 in the CMS line. Quantitative PCR analysis indicated that the expression level of atp9 in the CMS line was 0.937-fold that of its maintainer. Furthermore, the respiratory rate of anthers in the CMS line was markedly lower than that of its maintainer. The results indicated that the 47-bp deletion at the 3′ flanking sequence of atp9 and/or down-regulated expression of the atp9 gene in the CMS line might be closely related to CMS in kenaf. To confirm whether the 47-bp deletion was specific to cytoplasm of male sterile lines, another 21 varieties were used for further analysis. The results showed that the 47-bp deletion was specific to male sterile cytoplasm (MSC) of kenaf. Based on these, a specific molecular marker was developed to distinguish the MSC from male fertile cytoplasm of kenaf. 相似文献
998.
Xuemei Cheng Tianliang Zhang Jing Zhao Jingyang Zhou Hua Shao Zhonghua Zhou Fanling Kong Nannan Feng Yuan Sun Baode Shan Zhaolin Xia 《Mutation Research - Genetic Toxicology and Environmental Mutagenesis》2013,750(1-2):139-146
1,3-Butadiene (BD) has been classified as a human carcinogen, group I; however, the relationship between polymorphisms of glutathione S-transferases that metabolize BD and chromosomal damage is not clear. The present study used sister chromatid exchange (SCE) and cytokinesis-block micronucleus (CBMN) assays to detect chromosomal damage in peripheral lymphocytes of 44 BD-exposed workers and 39 non-exposed healthy controls. PCR and PCR-RFLP were employed to detect three known glutathione S-transferase polymorphisms GSTT1, GSTM1, and GSTP1 (Ile105Val). The data demonstrated that the micronucleus (CBMN) frequency in BD-exposed workers was significantly higher than that in controls (frequency ratio (FR) = 1.48, 95% CI: 1.14–1.91, P < 0.01), and the CBMN frequency was higher in workers exposed to higher cumulative BD levels (FR = 1.70, 95% CI: 1.28–2.27, P < 0.01). However, differences in SCE frequency were not observed (FR = 1.14, 95% CI: 0.81–1.61, P > 0.05). Among exposed workers, chromosomal damage was related to BD exposure levels (FR = 1.35, 95% CI: 1.02–1.80, P < 0.05); age, older workers exhibited higher MN frequencies than younger workers (FR = 1.45, 95% CI: 1.14–1.84, P < 0.05); and years of work, those with more years of work exhibited higher MN frequencies than those with fewer years (FR = 1.40, 95% CI: 1.10–1.77, P < 0.05). Multivariate Poisson regression analysis showed that those who carried GSTM1 (?) (FR = 1.48, 95% CI: 1.14–1.92) or GSTT1 (?) (FR = 1.42, 95% CI: 1.10–1.83) genotypes, and especially those who carried both (FR = 2.10, 95% CI: 1.43–3.09) exhibited significantly higher MN frequencies than those carrying GSTM1 (+), GSTT1 (+) genotypes or their combination. The GSTP1 Val genotype did not affect MN frequency (P > 0.05). Our results suggested that higher levels of BD exposure in the workplace resulted in increased chromosomal damage, and that polymorphisms in GSTT1 and GSTM1 genes might modulate the genotoxic effects of BD exposure. Furthermore, the GSTT1 and GSTM1 polymorphisms exhibited an additive effect. Finally, urinary DHBMA was found to provide a biomarker that correlated with airborne BD levels. 相似文献
999.
1000.
Alok Kumar Gupta Vikram Singh Gaur Sanjay Gupta Anil Kumar 《Functional & integrative genomics》2013,13(2):179-190
In order to understand the molecular basis of high nitrogen use efficiency of finger millet, five genes (EcHNRT2, EcLNRT1, EcNADH-NR, EcGS, and EcFd-GOGAT) involved in nitrate uptake and assimilation were isolated using conserved primer approaches. Expression profiles of these five genes along with the previously isolated EcDof1 was studied under increased KNO3 concentrations (0.15 to 1,500 μM) for 2 h as well as at 1.5 μM for 24 h in the roots and shoots of 25 days old nitrogen deprived two contrasting finger millet genotypes (GE-3885 and GE-1437) differing in grain protein content (13.76 and 6.15 %, respectively). Time kinetics experiment revealed that, all the five genes except EcHNRT2 in the leaves of GE-3885 were induced within 30 min of nitrate exposure indicating that there might be a greater nitrogen deficit in leaves and therefore quick transportation of nitrate signals to the leaves. Exposing the plants to increasing nitrate concentrations for 2 h showed that in roots of GE-3885, NR was strongly induced while GS was repressed; however, the pattern was found to be reversed in leaves of GE-1437 indicating that in GE-3885, most of the nitrate might be reduced in the roots but assimilated in leaves and vice-versa. Furthermore, compared with the low-protein genotype, expression of HNRT2 was strongly induced in both roots and shoots of high-protein genotype at the least nitrate concentration supplied. This further indicates that GE-3885 is a quick sensor of nitrogen compared with the low-protein genotype. Furthermore, expression of EcDof1 was also found to overlap the expression of NR, GS, and GOGAT indicating that Dof1 probably regulates the expression of these genes under different conditions by sensing the nitrogen fluctuations around the root zone. 相似文献