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981.
Zhen-hua Wang Xiao-han Cao Xiao-gang Du Hai-bo Feng Di-Wang He-Song Xian-yin Zeng 《Cellular immunology》2014
The purpose of the study was to construct mucosal vaccine of a recombinant Lactococcus lactis expressing PRRSV ORF6 gene and evaluate mucosal and systemic immune response against PRRSV in mice after intranasal immunization. The result show that the vaccine can stimulate mice to produce specific IgG in serum and remarkable special s-IgA in lung lavage fluid, at the same time, the contents of cytokines IL-2 and IFN-γ of the experimental group were significant higher than those of the control group (P < 0.01), however, the contents of cytokines IL-4 was not different to the all groups. In summary, the constructed mucosal vaccine can significantly induce mucosal immune, humoral immunity and cellular immunity involved Th1 type cytokines, which will lay a theoretical foundation on immune mechanism and new efficient vaccines for PRRSV. 相似文献
982.
Ke-Gui Li Zhen-Dong Cao Jiang-Lan Peng Shi-Jian Fu 《Journal of comparative physiology. B, Biochemical, systemic, and environmental physiology》2010,180(5):661-671
Feeding and exhaustive exercise are known to elevate metabolism. However, acid–base status may be oppositely affected by the
two processes. In this study, we first investigated the acid–base response of Chinese catfish to feeding (the meal size was
about 8% of body mass) to test whether an alkaline tide (a metabolic alkalosis created by gastric HCl secretion after feeding)
would occur. We then determined the combined effects of feeding and exhaustive exercise on excess post-exercise oxygen consumption
and acid–base status to determine whether the alkaline tide induced by feeding protects against acid–base disturbance during
exhaustive exercise and affects subsequent recovery. Arterial blood pH increased from 7.74 ± 0.02 before feeding to 7.88 ± 0.02
and plasma [HCO3
−]pl increased from 5.42 ± 0.29 to 7.83 ± 0.37 mmol L−1 6 h after feeding, while feeding had no significant effect on
P\textCO2 P_{{{\text{CO}}_{2} }} . Exhaustive exercise led to a significant reduction in pH by 0.46 units and a reduction of [HCO3
−]pl by ~3 mmol L−1. Lactate concentrations in white muscle and plasma increased by 2.4 mmol L−1 and 13.4 μmol g−1, respectively. Fed fish had a higher pH and [HCO3
−]pl than fasting fish at rest, and the reductions in pH (0.36 units) and [HCO3
−]pl (~2 mmol L−1) were thus lower after exhaustive exercise. However, the recovery of acid–base status and metabolites were similar in digesting
and fasting fish. Overall, a significant alkaline tide was found in Chinese catfish after feeding. The alkaline tide elicited
by feeding significantly prevented the decreases in pH and [HCO3
−]pl immediately after exhaustive exercise, but recovery from exhaustive exercise was not affected by digestion. 相似文献
983.
984.
Rong Pan Lixiang Cao Haiwei Huang Renduo Zhang Yu Mo 《Applied microbiology and biotechnology》2010,88(4):997-1005
In this study, dried and humid fruiting bodies of Tremella fuciformis and Auricularia polytricha were examined as cost-effective biosorbents in treatment of heavy metals (Cd2+, Cu2+, Pb2+, and Zn2+) in aqueous solution. The humid T. fuciformis showed the highest capacity to adsorb the four metals in the multi-metal solutions. The Pb2+ adsorption rates were 85.5%, 97.8%, 84.8%, and 91.0% by dried T. fuciformis, humid T. fuciformis, dried A. polytricha, and humid A. polytricha, respectively. The adsorption amount of Pb2+ by dried and humid T. fuciformis in Cd2+ + Pb2+, Cu2+ + Pb2+, Pb2+ + Zn2+, Cd2+ + Cu2+ + Pb2+, and Cd2+ + Zn2+ + Pb2+ solutions were not lower than that in Pb2+ solutions. The results suggested that in humid T. fuciformis, Cd2+, Cu2+, and Zn2+ promoted the Pb2+ adsorption by the biomass. In the multi-metal solutions of Cd2+ + Cu2+ + Pb2+ + Zn2+, the adsorption amount and rates of the metals by all the test biosorbents were in the order of Pb2+ > Cu2+ > Zn2+ > Cd2+. Compared with the pseudo first-order model, the pseudo second-order model described the adsorption kinetics much better,
indicating a two-step biosorption process. The present study confirmed that fruiting bodies of the jelly fungi should be useful
for the treatment of wastewater containing Cd2+, Cu2+, Pb2+, and Zn2+. 相似文献
985.
Shirley Chiang Tanya Burch Gary Van Domselaar Kevin Dick Alina Radziwon Craig Brusnyk Megan Rae Edwards Jessica Piper Todd Cutts Jingxin Cao Xuguang Li Runtao He 《Molecular and cellular biochemistry》2010,334(1-2):221-232
The cellular counterpart of the “soluble” guanylyl cyclase found in tissue homogenates over 30 years ago is now recognized as the physiological receptor for nitric oxide (NO). The ligand-binding site is a prosthetic haem group that, when occupied by NO, induces a conformational change in the protein that propagates to the catalytic site, triggering conversion of GTP into cGMP. This review focuses on recent research that takes this basic information forward to the beginnings of a quantitative depiction of NO signal transduction, analogous to that achieved for other major transmitters. At its foundation is an explicit enzyme-linked receptor mechanism for NO-activated guanylyl cyclase that replicates all its main properties. In cells, NO signal transduction is subject to additional, activity-dependent modifications, notably through receptor desensitization and changes in the activity of cGMP-hydrolyzing phosphodiesterases. The measurement of these parameters under varying conditions in rat platelets has made it possible to formulate a cellular model of NO-cGMP signaling. The model helps explain cellular responses to NO and their modification by therapeutic agents acting on the guanylyl cyclase or phosphodiesterase limbs of the pathway. 相似文献
986.
Xuanwen Li Li Xiong Chunliang Xie Jia Cao Huobao Deng Yong Lin Rui Cao Jianglin Li Ping Chen Songping Liang 《Molecular and cellular biochemistry》2010,344(1-2):137-150
Liver regeneration is an angiogenesis-associated phenomenon. To identify key plasma membrane (PM) proteins of endothelial cells involved in the initiation of angiogenesis during liver regeneration, the PM of liver sinusoidal endothelial cells (LSEC) at 72 h after partial hepatectomy was enriched by an established in vivo membrane density perturbation method. The differentially expressed membrane proteins compared to those from sham operation were quantified using an improved two-dimensional 16-BAC/SDS-PAGE and identified by LC-MS/MS. Several proteins were further confirmed by cICAT labeling quantitative strategy. A total of 47 proteins were identified including known and novel proteins involved in angiogenesis or liver regeneration, such as inducible nitric oxide synthase, type IV collagen, and integrin beta3. Our results indicated that the combination of the membrane density perturbation strategy and the improved two-dimensional electrophoresis (2-DE) method are useful for investigating the endothelial dysfunctions in vivo. 相似文献
987.
Jing Wang Wei-wei Zhang Jin-ni Liu Yao-ling Cao Xiao-ting Bai Yue-sheng Gong Pei-lin Cen Ming-ming Yang 《Molecular biology reports》2010,37(7):3297-3302
An alkaline active xylanase, XynBYG, was purified from an alkaliphilic Bacillus pumilus BYG, which was newly isolated from paper mill effluent. It had an optimum pH of 8.0–9.0, and showed good stability after
incubated at pH 9.0 for 120 min. The optimum temperature for the activity was 50°C, and the enzyme retained below 55% of its
original activity for 30 min at 55°C. The gene coding for XynBYG consists of 687 bp and encodes 229 amino acids. Similarity
analysis indicated that XynBYG belong to family 11 glycosyl hydrolases. Site-directed mutagenesis was performed to replace
five sites (Tyr/Ser) to Arg/Glu and the results demonstrated that the optimum temperature of the mutant Y7 (S39R-T146E) increased
5°C and the half-life of inactivation (T1/2) at 60 and 65°C was 1 h and 25 min, respectively. Thus, it provides a potential
xylanase that can meet the harsh conditions in the industrial applications. 相似文献
988.
Lei-Lei Chen Tie Bin Zhu Hang Yin Jun Huang Lian Sheng Wang Ke Jiang Cao Zhi Jian Yang 《Molecular biology reports》2010,37(7):3067-3072
Endothelial nitric oxide synthase (eNOS) and nitric oxide (NO) may play an important role in attenuating cardiac remodeling
and apoptosis after myocardial infarction. However, the anti-inflammation effects of eNOS in infarcted myocardium and the
role of MAPK signaling in eNOS/NO mediated cardiac remodeling have not yet been elucidated. Adenovirus carrying Human eNOS
gene was delivered locally into heart 4 days prior to induction of myocardial infarction (MI) by left anterior descending
coronary artery ligation. Monocyte/macrophage infiltration was detected by ED-1 immunohistochemistry. Western blot was employed
to examine the activation of MAPK. eNOS gene transfer significantly reduced myocardial infarct size and improved cardiac contractility
as well as left ventricle (LV) diastolic function at 7 days after MI. In addition, eNOS gene transfer decreased monocyte/macrophage
infiltration in the infarct region of the heart. Phosphorylation of MAPK after MI were also dramatically reduced by eNOS gene
transfer. All the protective effects of eNOS were blocked by N(ω)-nitro-l-arginine methyl ester (L-NAME) administration, indicating a NO-mediated event. These results demonstrate that the eNOS/NO
system provides cardiac protection after MI injury through inhibition of inflammation and suppression of MAPK signaling. 相似文献
989.
Sweet flag (Acorus calamus L.) and yellow flag (Iris pseudacorus L.) have been used increasingly in constructed wetlands (CWs) for treatment of eutrophic wastewater. In order to properly match plant species with the type of wastewater being treated, it is important to know the performance of plant species under different NO3−/NH4+ ratios. We investigated dry matter (DW) production and N content of A. calamus and I. pseudacorus under five NO3−/NH4+ ratios (100/0, 75/25, 50/50, 25/75, and 0/100) in a hydroponic system. Results showed that the two species exhibited different preferences for NO3− and NH4+. Total DW, shoot DW, and N content were greater with NO3−/NH4+ ratios of 50/50 and 75/25 than otherwise for A. calamus, but these parameters were only higher under the sole NO3− treatment in I. pseudacorus. We conclude that A. calamus could be best used for treating wastewater in constructed wetlands with NO3−/NH4+ ratios between 50/50 and 75/25, while I. pseudacorus for treating wastewater with NO3− only to achieve the highest biomass production and efficiency in the removal of N. 相似文献
990.
A female animal appears to approach an upper limit to the rate of sustained energy intake/metabolic rate (SusEI/MR) during lactation. However, different species of animals may respond differently to the sustainable limit. Here, we measured energy budget during lactation in female striped hamsters raising litters of natural size (Con), and females whose litter size was manipulated during early lactation to support fewer or more pups (minus pups, MP or plus pups, PP). The striped hamsters significantly decreased their body mass and increased food intake from early to late lactation; and MP females had lower weight loss and food intake than the control and PP females. Litter size of the PP group decreased significantly over the period of lactation, and pups were weaned at a similar weight to that of the controls. MP females supported a significantly lower litter mass throughout lactation compared with the control and PP females, but during late lactation the pups from the MP group were significantly heavier. Resting metabolic rate (RMR) did not differ significantly between the three groups and the gross energy intake during peak lactation was 5.0×, 4.2× and 5.0 × RMR for the control, MP and PP females, respectively. Female striped hamsters reached a plateau in food intake at around 14 g/d during peak lactation, which might signify a limit of SusEI at 5.0 × RMR. However, it was not possible to determine whether the limitation on SusEI was imposed centrally by the capacity of the gastrointestinal tract to process food, peripherally by the capacity of the mammary gland to produce milk, or by the capacity of animals to dissipate heat. 相似文献