Publications by authors named "Xian-Hui Wang"

22 Publications

  • Page 1 of 1

Effect of Sleep-Disordered Breathing During Rapid Eye Movement Sleep and Non-Rapid Eye Movement sleep on Acute Ischemic Stroke.

J Stroke Cerebrovasc Dis 2021 Aug 12;30(8):105913. Epub 2021 Jun 12.

Department of Neurology and Suzhou Clinical Research Center of Neurological Disease, The Second Affiliated Hospital of Soochow University, Suzhou 215004, China; Department of Neurology, Taicang Affiliated Hospital of Soochow University, The first People's Hospital of Taicang, Taicang 215400, China; Jiangsu Key Laboratory of Neuropsychiatric Diseases and Institute of Neuroscience, Soochow University, Suzhou 215123, China. Electronic address:

Objectives: Sleep-disordered breathing adversely impacts stroke outcomes. We investigated whether sleep-disordered breathing during rapid eye movement sleep and non-rapid eye movement sleep differentially influenced stroke outcomes.

Materials And Methods: Acute ischemic stroke patients who finished polysomnography within 14 days of stroke onset from April 2010 to August 2018 were reviewed. Patients were divided into four groups according to apnea-hypopnea index during rapid eye movement sleep and non-rapid eye movement sleep. The modified Rankin Scale was used to evaluate short-term outcome. During January and April 2019, another follow-up was performed for long-term outcomes, including stroke-specific quality-of-life scale, modified Rankin Scale, stroke recurrence and death.

Results: Of 140 patients reviewed, 109 were finally recruited. Although patients with sleep-disordered breathing during non-rapid eye movement sleep only and with sleep-disordered breathing during both rapid eye movement sleep and non-rapid eye movement sleep had higher apnea-hypopnea indices and more disrupted sleep structures, short-term and long-term outcomes did not significantly different between four groups. In Logistic regression analysis, apnea-hypopnea index (p = 0.013, OR 1.023, 95%CI 1.005-1.042) was found independently associated with short-term outcome. Rapid eye movement sleep latency (p = 0.045, OR 0.994, 95%CI 0.987-1.000) was found independently associated with quality of life. Apnea-hypopnea indices during rapid eye movement sleep or non-rapid eye movement sleep were not significantly associated with short-term or long-term outcomes.

Conclusions: Apnea-hypopnea index is an independent risk factor of short-term outcome of acute ischemic stroke while sleep-disordered breathing during rapid eye movement sleep and non-rapid eye movement sleep do not affect stroke outcomes differently.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.jstrokecerebrovasdis.2021.105913DOI Listing
August 2021

BMAL1 regulation of microglia-mediated neuroinflammation in MPTP-induced Parkinson's disease mouse model.

FASEB J 2020 05 4;34(5):6570-6581. Epub 2020 Apr 4.

Department of Neurology and Suzhou Clinical Research Center of Neurological Disease, The Second Affiliated Hospital of Soochow University, Suzhou, China.

Dysfunction of the circadian rhythm is one of most common nonmotor symptoms in Parkinson's disease (PD), but the molecular role of the circadian rhythm in PD is unclear. We here showed that inactivation of brain and muscle ARNT-like 1 (BMAL1) in 1-methyl-4-phenyl-1,2,4,5-tetrahydropyridine (MPTP)-treated mice resulted in obvious motor functional deficit, loss of dopaminergic neurons (DANs) in the substantia nigra pars compacta (SNpc), decrease of dopamine (DA) transmitter, and increased activation of microglia and astrocytes in the striatum. Time on the rotarod or calorie consumption, and food and water intake were reduced in the Bmal1 mice after MPTP treatment, suggesting that absence of Bmal1 may exacerbate circadian and PD motor function. We observed a significant reduction of DANs (~35%) in the SNpc, the tyrosine hydroxylase protein level in the striatum (~60%), the DA (~22%), and 3,4-dihydroxyphenylacetic acid content (~29%), respectively, in MPTP-treated Bmal1 mice. Loss of Bmal1 aggravated the inflammatory reaction both in vivo and in vitro. These findings suggest that BMAL1 may play an essential role in the survival of DANs and maintain normal function of the DA signaling pathway via regulating microglia-mediated neuroinflammation in the brain.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1096/fj.201901565RRDOI Listing
May 2020

JumpDetector: An automated monitoring equipment for the locomotion of jumping insects.

Insect Sci 2020 Jun 21;27(3):613-624. Epub 2019 May 21.

State Key Laboratory of Integrated Management of Pest Insects and Rodents, Institute of Zoology, Chinese Academy of Sciences, Beijing, China.

Continuous jumping behavior, a kind of endurance locomotion, plays important roles in insect ecological adaption and survival. However, the methods used for the efficient evaluation of insect jumping behavior remain largely lacking. Here, we developed a locomotion detection system named JumpDetector with automatic trajectory tracking and data analysis to evaluate the jumping of insects. This automated system exhibits more accurate, efficient, and adjustable performance than manual methods. By using this automatic system, we characterized a gradually declining pattern of continuous jumping behavior in 4th-instar nymphs of the migratory locust. We found that locusts in their gregarious phase outperformed locusts in their solitary phase in the endurance jumping locomotion. Therefore, the JumpDetector could be widely used in jumping behavior and endurance locomotion measurement.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1111/1744-7917.12668DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7277037PMC
June 2020

Genomic data reveal high conservation but divergent evolutionary pattern of Polycomb/Trithorax group genes in arthropods.

Insect Sci 2019 Feb 18;26(1):20-34. Epub 2017 Dec 18.

Beijing Institutes of Life Science, Chinese Academy of Sciences, Beijing, China.

Epigenetic gene control is maintained by chromatin-associated Polycomb group (PcG) and Trithorax group (TrxG) genes, which act antagonistically via the interplay between PcG and TrxG regulation to generate silenced or permissive transcriptional states. In this study, we searched for PcG/TrxG genes in 180 arthropod genomes, covering all the sequenced arthropod genomes at the time of conducting this study, to perform a global investigation of PcG/TrxG genes in a phylogenetic frame. Results of ancestral state reconstruction analysis revealed that the ancestor of arthropod species has an almost complete repertoire of PcG/TrxG genes, and most of these genes were seldom lost above order level. The domain diversity analysis indicated that the PcG/TrxG genes show variable extent of domain structure changes; some of these changes could be associated with lineage-specific events. The likelihood ratio tests for selection pressure detected a number of PcG/TrxG genes which underwent episodic positive selection on the branch leading to the insects with holometabolous development. These results suggest that, despite their high conservation across arthropod species, different members of PcG/TrxG genes showed considerable differences in domain structure and sequence divergence in arthropod evolution. Our cross species comparisons using large-scale genomic data provide insights into divergent evolutionary pattern on highly conserved genes in arthropods.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1111/1744-7917.12558DOI Listing
February 2019

MiR-509-3-5p causes aberrant mitosis and anti-proliferative effect by suppression of PLK1 in human lung cancer A549 cells.

Biochem Biophys Res Commun 2016 09 3;478(2):676-82. Epub 2016 Aug 3.

Department of Biochemistry and Molecular Biology, Beijing Key Laboratory of Protein Posttranslational Modifications and Cell Function, School of Basic Medical Sciences, Peking University Health Science Center, Beijing, 100191, PR China. Electronic address:

MicroRNAs (miRNAs) are potent post-transcriptional regulators of gene expression and play roles in DNA damage response (DDR). PLK1 is identified as a modulator of DNA damage checkpoint. Although down-regulation of PLK1 by certain microRNAs has been reported, little is known about the interplay between PLK1 and miR-509-3-5p in DDR. Here we have demonstrated that miR-509-3-5p repressed PLK1 expression by targeting PLK1 3'-UTR, thereby causing mitotic aberration and growth arrest of human lung cancer A549 cells. Repression of PLK1 by miR-509-3-5p was further evidenced by over-expression of miR-509-3-5p in A549, HepG2 and HCT116p53(-/-) cancer cells, in which PLK1 protein was suppressed. Consistently, miR-509-3-5p was stimulated, while PLK1 protein was down-regulated in A549 cells exposed to CIS and ADR, suggesting that suppression of PLK1 by miR-509-3-5p is a component of CIS/ADR-induced DDR pathway. Flow cytometry and immunofluorescence labeling showed that over-expression of miR-509-3-5p in A549 induced G2/M arrest and aberrant mitosis characterized by abnormal bipolar mitotic spindles, condensed chromosomes, lagging DNA and chromosome bridges. In addition, over-expression of miR-509-3-5p markedly blocked A549 cell proliferation and sensitized the cells to CIS and ADR treatment. Taken together, miR-509-3-5p is a feasible suppressor for cancer by targeting PLK1. Our data may provide aid in potential design of combined chemotherapy and in our better understanding of the roles of microRNAs in response to DNA damage.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.bbrc.2016.08.006DOI Listing
September 2016

Leap forward with insect genomics.

Insect Sci 2016 Jun;23(3):332-4

Key Laboratory of Insect Development and Evolutionary Biology, Institute of Plant Physiology and Ecology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai, China.

View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1111/1744-7917.12355DOI Listing
June 2016

Hydrogen sulfide attenuates ferric chloride-induced arterial thrombosis in rats.

Free Radic Res 2016 Jun 25;50(6):654-65. Epub 2016 Apr 25.

a Department of Neurology, Jiangsu Key Laboratory of Translational Research and Therapy for Neuro-Psycho-Diseases , The Second Affiliated Hospital of Soochow University , Suzhou , China ;

Hydrogen sulfide (H2S) is a novel gaseous transmitter, regulating a multitude of biological processes in the cardiovascular and other systems. However, it remains unclear whether it exerts any effect on arterial thrombosis. In this study, we examined the effect of H2S on ferric chloride (FeCl3)-induced thrombosis in the rat common carotid artery (CCA). The results revealed a decrease of the H2S-producing enzyme cystathionine γ-lyase (CSE) expression and H2S production that persisted until 48 h after FeCl3 application. Intriguingly, administration with NaHS at appropriate regimen reduced the thrombus formation and enhanced the blood flow, accompanied with the alleviation of CSE and CD31 downregulation, and endothelial cell apoptosis in the rat CCA following FeCl3 application. Moreover, the antithrombotic effect of H2S was also observed in Rose Bengal photochemical model in which the development of thrombosis is contributed by oxidative injury to the endothelium. The in vitro study demonstrated that the mRNA and protein expression of CSE, as well as H2S production, was decreased in hydrogen peroxide (H2O2)-treated endothelial cells. Exogenous supplement of NaHS and CSE overexpression consistently alleviated the increase of cleaved caspase-3 and endothelial cell damage caused by H2O2. Taken together, our findings suggest that endogenous H2S generation in the endothelium may be impaired during arterial thrombosis and that modulation of H2S, either exogenous supplement or boost of endogenous production, may become a potential venue for arterial thrombosis therapy.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3109/10715762.2016.1164311DOI Listing
June 2016

Molecular characterization, tissue and developmental expression profiles of cryptochrome genes in wing dimorphic brown planthoppers, Nilaparvata lugens.

Insect Sci 2016 Dec 26;23(6):805-818. Epub 2015 Oct 26.

Beijing Key Laboratory of Bioelectromagnetics, Institute of Electrical Engineering, Chinese Academy of Sciences, Beijing, China.

Cryptochromes (CRYs) are blue and UV light photoreceptors, known to play key roles in circadian rhythms and in the light-dependent magnetosensitivity of insects. Two novel cryptochrome genes were cloned from the brown planthopper, and were given the designations of Nlcry1 and Nlcry2, with the accession numbers KM108578 and KM108579 in GenBank. The complementary DNA sequences of Nlcry1 and Nlcry2 are 1935 bp and 2463 bp in length, and they contain an open reading frame of 1629 bp and 1872 bp, encoding amino acids of 542 and 623, with a predicted molecular weight of 62.53 kDa and 70.60 kDa, respectively. Well-conserved motifs such as DNA-photolyase and FAD-binding-7 domains were observed in Nlcry1 and Nlcry2. Phylogenetic analysis demonstrated the proteins of Nlcry1 and Nlcry2 to be clustered into the insect's cryptochrome 1 and cryptochrome 2, respectively. Quantitative polymerase chain reaction showed that the daily oscillations of messenger RNA (mRNA) expression in the head of the brown planthopper were mild for Nlcry1, and modest for Nlcry2. Throughout all developmental stages, Nlcry1 and Nlcry2 exhibited extreme fluctuations and distinctive expression profiles. Cryptochrome mRNA expression peaked immediately after adult emergence and then decreased subsequently. The tissue expression profiles of newly emerged brown planthopper adults showed higher expression levels of CRYs in the head than in the thorax or abdomen, as well as significantly higher levels of CRYs in the heads of the macropterous strain than in the heads of the brachypterous strain. Taken together, the results of our study suggest that the two cryptochrome genes characterized in the brown planthopper might be associated with developmental physiology and migration.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1111/1744-7917.12256DOI Listing
December 2016

Downregulation of cystathionine β-synthase/hydrogen sulfide contributes to rotenone-induced microglia polarization toward M1 type.

Biochem Biophys Res Commun 2014 Aug 30;451(2):239-45. Epub 2014 Jul 30.

Jiangsu Key Laboratory of Translational Research and Therapy for Neuro-Psycho-Diseases and Institute of Neuroscience, Soochow University, Suzhou, Jiangsu 215021, China; Department of Pharmacology, School of Pharmaceutical Science, Soochow University, Suzhou 215123, China. Electronic address:

Microglia-mediated neuroinflammation is implicated in the pathogenesis of several neurodegenerative disorders. Microglia can be activated and polarized to exert pro- or anti-inflammatory roles in response to specific stimulus. Rotenone is an environmental toxin that has been shown to activate microglia and neuroinflammation. However, the effects and mechanisms of rotenone on microglia polarization are poorly studied. In the present study, we demonstrated that rotenone enhanced the levels of M1 phenotypic genes including TNF-α, iNOS and COX-2/PGE2 but reduced that of M2 markers such as Ym1/2 and IL-10 in mouse primary and immortalized microglia. Moreover, the transcription and protein expression of cystathionine-β-synthase (CBS), as well as hydrogen sulfide (H2S) production were decreased in rotenone-treated primary microglia. Elevating endogenous H2S via CBS over-expression in immortalized microglia not only reduced the expression of pro-inflammatory M1 genes, but also enhanced the anti-inflammatory M2 marker IL-10 production in response to rotenone stimulation as compared to vector-transfected cells. Similarly, pretreatment with H2S donor NaHS (50, 100 and 500μmol/L) attenuated the increases of M1 gene expression triggered by rotenone treatment, and enhanced the M2 gene Ym1/2 expression in mouse primary microglia. In addition, we observed reactive oxygen species (ROS) scavenger N-acetyl-l-cysteine reversed the down-regulation of CBS and H2S generation caused by rotenone in microglia. NaHS pretreatment also decreased the ROS formation in rotenone-stimulated microglia. Taken together, these results reveal that probably via triggering ROS formation, rotenone suppressed the CBS-H2S pathway and thus promoted microglia polarization toward M1 pro-inflammatory phenotype.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.bbrc.2014.07.107DOI Listing
August 2014

Dysregulation of cystathionine γ-lyase (CSE)/hydrogen sulfide pathway contributes to ox-LDL-induced inflammation in macrophage.

Cell Signal 2013 Nov 18;25(11):2255-62. Epub 2013 Jul 18.

Institute of Neuroscience, Soochow University, Suzhou 215123, China.

Hydrogen sulfide (H2S), mainly produced by cystathionine γ-lyase (CSE) in vascular system, emerges as a novel gasotransmitter exerting anti-inflammatory and anti-atherosclerotic effects. Alterations of CSE/H2S pathway may thus be involved in atherosclerosis pathogenesis. However, the underlying mechanisms are poorly understood. The present study showed that the levels of CSE mRNA and protein expression, as well as H2S production were decreased in ox-LDL-treated macrophage. CSE overexpression reduced the ox-LDL-stimulated tumor necrosis factor-α (TNF-α) generation in Raw264.7 and primary macrophage while CSE knockdown enhanced it. Exogenous supplementation of H2S with NaHS and Na2S also decreased the production of TNF-α and intercellular adhesion molecule-1 (ICAM-1) in ox-LDL-stimulated macrophage, and alleviated the adhesion of macrophage to endothelial monolayer. Cysteine, a CSE preferential substrate for H2S biosynthesis, produced similar effects on the pro-inflammatory cytokine generation, which were reversed by CSE inhibitors PAG and BCA, respectively. Moreover, NaHS and Na2S attenuated the phosphorylation and degradation of IκBα and p65 nuclear translocation, as well as JNK activation caused by ox-LDL. The JNK inhibitor suppressed the NF-κB transcription activity in ox-LDL-treated cells. Furthermore, inhibitors of NF-κB (PDTC), ERK (U0126 and PD98059) and JNK (SP600125) partially blocked the suppression by ox-LDL on the CSE mRNA levels. Taken together, the findings demonstrate that ox-LDL may down-regulate the CSE/H2S pathway, which plays an anti-inflammatory role in ox-LDL-stimulated macrophage by suppressing JNK/NF-κB signaling. The study reveals new therapeutic strategies for atherosclerosis, based on modulating CSE/H2S pathway.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.cellsig.2013.07.010DOI Listing
November 2013

Characterization of extracellular proteins produced by Aeromonas hydrophila AH-1.

Proteomics 2007 Feb;7(3):436-49

Department of Biological Sciences, Faculty of Science, National University of Singapore, Singapore, Singapore.

Aeromonas hydrophila is a ubiquitous Gram-negative bacterium which can cause motile aeromonad septicemia in both fish and humans. A. hydrophila secretes many extracellular proteins associated with pathogenicity and environmental adaptability. In this study, an extracellular proteome map of A. hydrophila AH-1 was constructed. The major extracellular virulence factors were characterized by comparing the proteomes of various deletion mutants with that of the wild type. The results suggested that serine protease was involved in the processing of a toxin and secreted enzymes such as hemolysin, glycerophospholipid-cholesterol acyltransferase and metalloprotease. We also showed that expressions of polar and lateral flagellins were under the control of temperature, FlhA, LafK, and RpoN. In addition, three novel proteins (potential effector proteins including one ExoT-like protein) were revealed to be secreted via the type III secretion system (TTSS) of A. hydrophila AH-1. Another novel finding was the demonstration of a crosstalk between the lateral flagellar system and the TTSS in A. hydrophila. These results showed that proteomics is a powerful tool for characterizing virulence factors. The construction of proteome maps will provide a valuable means of finding potential candidates for developing suitable diagnostics and therapeutics for this emerging pathogen.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1002/pmic.200600396DOI Listing
February 2007

Targeting radioimmunotherapy of hepatocellular carcinoma with iodine (131I) metuximab injection: clinical phase I/II trials.

Int J Radiat Oncol Biol Phys 2006 Jun;65(2):435-44

Cell Engineering Research Centre and Department of Cell Biology, State Key Laboratory of Cancer Biology, Fourth Military Medical University, Xi'an, China.

Purpose: HAb18G/CD147 is a hepatocellular carcinoma (HCC)-associated antigen. We developed iodine (131I) metuximab injection (Licartin), a novel 131I-labeled HAb18G/CD147-specific monoclonal antibody Fab'2 fragment, and evaluated its safety, pharmacokinetics, and clinical efficacy on HCC in Phase I/II trials.

Methods And Materials: In a Phase I trial, 28 patients were randomly assigned to receive the injection in 9.25-, 18.5-, 27.75-, or 37-MBq/kg doses by hepatic artery infusion. In a multicenter Phase II trial, 106 patients received the injection (27.75 MBq/kg) on Day 1 of a 28-day cycle. Response rate and survival rate were the endpoints.

Results: No life-threatening toxic effects were found. The safe dosage was 27.75 MBq/kg. The blood clearance fitted a biphasic model, and its half-life was 90.56-63.93 h. In the Phase II trial, the injection was found to be targeted and concentrated to tumor tissues. Of the 73 patients completing two cycles, 6 (8.22%) had a partial response, 14 (19.18%) minor response, and 43 (58.90%) stable disease. The 21-month survival rate was 44.54%. The survival rate of progression-free patients was significantly higher than that of patients with progressive disease after either one or two cycles (p < 0.0001 or p = 0.0019).

Conclusion: Iodine (131I) metuximab injection is safe and active for HCC patients.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.ijrobp.2005.12.034DOI Listing
June 2006

Differences in egg thermotolerance between tropical and temperate populations of the migratory locust Locusta migratoria (Orthoptera: Acridiidae).

J Insect Physiol 2005 Nov 15;51(11):1277-85. Epub 2005 Sep 15.

State Key Laboratory of Integrated Management of Pest Insects and Rodents, Institute of Zoology, The Chinese Academy of Sciences, 25 BeiXisihuan Road, Haidian, Beijing 100080, PR China.

The migratory locust Locusta migratoria L., which is widely distributed throughout the world, exhibits within- and between-population variation in cold tolerance. To understand physiological adaptation in populations, we studied the genetic basis of thermotolerance in Hainan (tropical) and Liaoning (temperate) populations and measured expression of Hsp70 and Hsp90 mRNA in both populations at low (0 degrees C) and high temperatures (40 degrees C). Phenotypic variation of thermotolerance is heritable. Heritable characteristics differed among different stages of locust egg development, as well as among different measures of thermotolerance. Nuclear genetic factors, rather than cytoplasmic factors, contribute to differences in cold tolerance between the tropical and temperate populations of the migratory locust; for heat tolerance, maternal effects were involved in three stages of egg development. Expression of Hsp90 mRNA was induced in temperate population after heat shock (40 degrees C x 12h), whereas expression of Hsp70 and 90 was induced in tropical population after cold shock (0 degrees C x 12h). We suggest that thermotolerance of locust eggs has a complex genetic basis and heat shock proteins may be involved in differences of thermotolerance between locust populations.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.jinsphys.2005.07.010DOI Listing
November 2005

[Modification of the antiapoptotic ability of H18 hybridoma cells].

Sheng Wu Gong Cheng Xue Bao 2003 Nov;19(6):705-8

Cell Engineering Research Centre, The Fourth Military Medical University, Xi'an 710033, China.

To construct eukaryotic expression vector containing murine bcl-XL and stably express it in H18 hybridoma cells in order to enhance hybridoma cells antiapoptotic ability. PCR was used to obtain 710bp murine bcl-XL cDNA from pGEM-T-bcl-XL. Then the recombinant expression vector pEF-bcl-XL was constructed by cloning bcl-XL cDNA into eukaryotic expression vector pEF by Pst I and Xho I double digestion. After transfection into H18 hybridoma cells through lipofectamine 2000, the stable expression cell line was screened by 800mg/L G418. The expression of bcl-XL gene was detected by Western blotting. Flow cytometer was used to test the modified hybridoma cells ability to resist apoptosis induced by 0.4mmol/L Sodium Butyrate. The eukaryotic expression vector pEF-bcl-XL was successfully constructed and stably expressed in H18 hybridoma cells. Our data showed that stably transfected H18 cells expressed high levels of Bcl-XL. Under the condition of 0.4mmol/L NaBu, the production of antibody was to be significantly increased by more than 3-fold in stably transfected H18, which resulted from suppressing the NaBu-induced apoptosis and allowing stably transfected H18 cells to grow at higher viability and extend culture longevity by > 3 days. The increased culture longevity by inhibition of NaBu-induced apoptosis by inducible expression of Bcl-XL combined with the enhanced secretion of antibody by NaBu contributed to the enhancement of final antibody concentration in the stably transfected H18 cells culture. The final antibody concentration of stably transfected H18 cells in the presence of NaBu was three-fold higher than that of H18 cells culture in the absence of NaBu. Together, our results showed that butyrate is of practical interest for production of antibody. NaBu-induced apoptosis of hybridoma cells could be inhibited by inducible expression of Bcl-XL. The expression of murine bcl-XL gene in hyridoma cells and the increasing antiapoptosis ability of hybridoma cells are of significance in further use of hybridoma cells in high density large scale cell culture.
View Article and Find Full Text PDF

Download full-text PDF

Source
November 2003

[On-line monitoring of oxygen uptake rate and its application in hybridoma culture].

Sheng Wu Gong Cheng Xue Bao 2003 Sep;19(5):593-7

Cell Engineering Research Centre, Fourth Military Medical University, Xi'an 710033, China.

On-line analysis and control are critical for the optimization of product yields in animal cell culture. The close monitor of viable cell number helps to gain a better insight into the metabolism and to refine culture strategy. In this study, we use the oxygen uptake rate (OUR) to estimate the number of viable cell and the OUR-based feed-back control strategy for nutrients feeding to improve the efficiency of cell culture. A hybridoma cell line (HAb18) was cultured in fed-batch and perfusion model using serum free medium in 5L CelliGen Plus bioreactor (NBS Co., American) and 5L Biostat B bioreactor (Braun Co., Germany). The system and the method for online monitoring OUR in bioreactors, based on the dynamic measurement of dissolved oxygen (DO), were developed. The method of on-line cell concentration estimation was established based on the relationship between the growth of the hybridoma and the uptake rate of oxygen. This method was then used to determine OUR and the concentrations of cell, antibody, glucose, lactate, glutamine and ammonia in the bioreactors at given times. The relationship between OUR and nutrients metabolism was studied and OUR-based feed-back control strategy, which used the state deltaOUR = 0 as the regulation point, was established and used to control the rates of nutrients or medium feeding rate in the perfusion culture. The results showed that there was close relationship between OUR, concentration of live cells, productivity of antibody and consumption of glutamine. The sudden decrease in OUR may be caused by glutamine depletion, and with different delay times, the viable cell concentration and antibody productivity also decreased. The further analysis revealed the linear relationship between OUR and the density of live cells in the exponential growth phase as qOUR = (0.103 +/- 0.028) x 10(-12) mol/cell/h. These findings can be applied to the on-line detection of live cell density. Our study also indicated that by adjusting the perfusion rate with OUR-based feed-back control strategy, it is feasible to continuously increase in viable cell density and antibody concentration in the perfusion culture.
View Article and Find Full Text PDF

Download full-text PDF

Source
September 2003

[DMSO arrested hybridoma cells for enhanced antibody production].

Sheng Wu Gong Cheng Xue Bao 2004 Jul;20(4):568-71

Cell Engineering Research Centre, The Fourth Military Medical University, Xi' an 710033, China.

Dimethyl sulfoxide (DMSO), a well-known differentiation inducer in several myeloid cells, induces G1 phase arrest in many cell lines. In this study, we investigated the possibility of using DMSO to arrest H18 hybridoma cells to the G1 phase and monitor whether the arrest improves antibody production. We showed that DMSO in concentration ranging between 0.3% and 0.6% efficiently arrested H18 hybridoma cells in G1 phase. In our experiment, > 80% of cells grown for 36h in presence of the 0.6% DMSO were arrested in G1. Furthermore, expression levels of P27 were up-regulated tow fold during the G1 phase. Higher concentration of DMSO at 0.9% leads to cytotoxicity. Herein we show a simple way, a two-stage process for antibody production, which consists of a proliferation phase leading to the desired cell density, followed by an extended production phase during which the cells remain at G1 phase. Our observation that the addition of DMSO results in increase antibody production is of significance in further use of hybridoma cells in high density large scale cell culture.
View Article and Find Full Text PDF

Download full-text PDF

Source
July 2004

[Purification of colorectal cancer-associated antigen by immuno-affinity chromatography].

Xi Bao Yu Fen Zi Mian Yi Xue Za Zhi 2004 May;20(3):348-51

Department of Cell Biology, Fourth Military Medical University, Xi'an 710032, China.

Aim: To purify and characterize the colorectal cancer-associated antigen from cultured colorectal cancer cells.

Methods: The colorectal cancer cell lines that highly expressed the associated antigen were selected by flow cytometry with five specific monoclonal antibodies (mAbs) CYL1-5. Western blot was used to determine the binding ability of five mAbs to the associated antigens released from colorectal cells lysed with single or triplex-detergent, respectively. The mAb with highest binding ability was employed as the ligand for the immuno-affinity chromatography. The antigens purified through immuno-affinity chromatography were identified by Western blot.

Results: The associated antigens were highly expressed on the colorectal cancer cell lines Hce-8693. The binding ability of mAb CYL-2 to the antigen was higher than that of CYL-1, CYL-3-5. The purified associated antigen binding to mAb CYL-2 was a heterodimer composed of two subunits with relative molecular mass (M(r)) of 60 x 10(3) and 70 x 10(3), respectively.

Conclusion: The purified associated-antigen binding to mAb CYL-2 was obtained from the colorectal cancer cell line Hce-8693 through immuno-affinity chromatography with mAb CYL-2.
View Article and Find Full Text PDF

Download full-text PDF

Source
May 2004

Inducible expression of Bcl-XL inhibits sodium butyrate-induced apoptosis in hybridoma, resulting in enhanced antibody production.

Cell Biol Int 2004 ;28(3):185-91

Cell Engineering Research Centre, Fourth Military Medical University, 17 Western Changle Road, Xi'an 710032, China.

Sodium butyrate (NaBu) can increase the specific Mab production rate of hybridomas by enhancing histone hyperacetylation and influencing the cell cycle, but it can also inhibit cell growth and induce apoptosis. Thus, the beneficial effect of NaBu on Mab secretion is compromised by its cytotoxic effect. In the present study, expression of the anti-apoptotic protein human Bcl-XL was made inducible in hybridoma H18 to overcome the cytotoxic effect of NaBu, circumventing the detrimental effects of constitutive high-level expression. We constructed an expression vector in which the promoter of a mammalian metallothionein (MT) gene drove the expression of bcl-XL in response to metal exposure. The vector was then used to exogenously control the expression of bcl-XL in H18 hybridoma cells. Our data showed that stably transfected H18.D4 cells expressed high levels of Bcl-X(L), which was induced within 24 h of addition of ZnSO4. NaBu (0.4 mM) increased antibody production by more than 3-fold in H18.D4. This effect resulted from the suppression of NaBu-induced apoptosis, allowing the H18.D4 cells to grow at higher viability and extending culture longevity by >3 days.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.cellbi.2003.11.018DOI Listing
October 2004

Rapid cold hardening in young hoppers of the migratory locust Locusta migratoria L. (Orthoptera: Acridiidae).

Cryo Letters 2003 Sep-Oct;24(5):331-40

State Key Laboratory of Integrated Management of Pest Insects and Rodents, Institute of Zoology, the Chinese Academy of Sciences, Beijing, China.

This paper describes a rapid cold hardening process for first instar hoppers of the migratory locust Locusta migratoria L. First instar hoppers of this species are often subjected to subzero temperatures or frosts in early April or May after their emergence from the soil. The mean supercooling point of hoppers is -13.0 +/- 1.4 degrees C; the fact that none could survive this temperature suggests they are freezing intolerant. When young hoppers were transferred directly from 30 degrees C to -7 degrees C for 2 h, there was only 35.8% survival. However, exposure to 0 degrees C for 2 h prior to transfer to -7 degrees C increased the apparent survival to 75%. A similar rapid cold hardening response can also be induced by gradual cooling at rates of between 0.05 and 0.1 degreess C min(-1). Rapid cold hardening also elevates the Ltime50 of first instar hoppers at -7 degrees C by approximately 3 fold, and reduces the lethal temperature from -10 degrees C to -12 degrees C. However, the protection from cold shock gained through rapid cold hardening was transient and easily lost within 2 h of hoppers being returned to 30 degrees C. The rapid cold hardening response is possibly advantageous to first instar hoppers that are often exposed to large temperature fluctuations in spring or early summer.
View Article and Find Full Text PDF

Download full-text PDF

Source
March 2004

[Experimental study of corpus cavernosal nerve evoked potential in diabetic rats].

Zhonghua Nan Ke Xue 2003 Jun;9(3):181-3

Department of Internal Medicine, Chengdu University of Traditional Chinese Medicine, Chengdu, Sichuan 610075, China.

Objectives: To observe the cavernosal nerve dysfunction of diabetic Sprague Dawley rats.

Methods: Thirty-five Sprague-Dawley rats were divided randomly into diabetes model group(n = 25) and normal group(n = 10). Diabetes model was established by administration of streptozotocin (63 mg/kg) in single intraperitoneal dosing. Giving single wave stimulus, corpus cavernosal nerve was measured for its latent period of reaction and myopotential.

Results: Compared with other groups, diabetic rats had longer reflection latent period(P < 0.01) and higher corpus cavernosum smooth muscle myopotential (P < 0.01).

Conclusions: The results indicate that corpus cavernosal nerve dysfunction may play an important role in the erectile dysfunction of diabetic rats.
View Article and Find Full Text PDF

Download full-text PDF

Source
June 2003

[Bio-panning of antagonistic peptides against HAb18G/CD147 and their function of anti-hepatoma invasion].

Zhonghua Zhong Liu Za Zhi 2003 Mar;25(2):111-4

Cell Engineering Research Center, Fourth Military Medical University, Xi'an 710032, China.

Objective: To screen out the HAb18G/CD147 binding peptides and find out an antagonist against hepatoma invasion.

Methods: HAb18G/CD147 was purified by affinity chromatographic method and the antigen binding peptides acquired by bio-panning a phage-displayed 12-peptide library. After obtaining the sequence of the selected phage-displayed peptides, all the 9 peptides were synthesized by solid-phase method and identified by mass spectrograph. The peptides' anti-metastatic function was tested by Boyden Chamber assay.

Results: The purified HAb18G/CD147, identified by Western blot (molecular weight about 65 kd) could be used to bio-pan the phage-displayed peptide library. After 3 rounds of bio-panning, 9 positive phage clones were selected and sequenced. The synthesized peptides had uneven inhibitory activities and three of them were able to markedly inhibit the hepatoma cell invasion (P < 0.01). The most effective peptide decreased by 90.1% of hepatoma cells migrating through the Boyden Chamber membrane as compared with the control.

Conclusion: Bio-panning the phage-displayed peptide library can be used successfully to screen out the antigen binding peptides. Hepatoma metastatic potential can be inhibited by peptide antagonist which could be a good foundation of developing peptide therapeutic agent against hepatoma metastasis.
View Article and Find Full Text PDF

Download full-text PDF

Source
March 2003

[The role of vagal innervation in the variability of heart beat].

Sheng Li Xue Bao 2002 Apr;54(2):129-32

Insititute of Neurosciences, The Fourth Military Medical University, Xi an 710032.

To determine the role of vagi in heart rate variability, conscious rabbits were employed and electrocardiogram was recorded under conditions of bilateral vagi intact, unilateral vagotomy, and bilateral vagotomy. The variability of RR intervals (RRI) was analyzed using power spectrum and approximate entropy (ApEn). The results showed that the values of high frequency power (HF) component, low frequency power (LF) component and ApEn in animals with bilateral vagi intact were the highest, but the LF/HF ratio was the lowest; unilateral vagotomy decreased ApEn, right vagotomy increased LF/HF ratio but left vagotomy did not; the LF/HF ratio increased while ApEn decreased significantly in animals with bilateral vagotomy. It is suggested that the variability of RRI is mainly regulated by the vagi and the role of right vagi is more important than that of the left. When measuring heart rate variability, the results obtained with conventional method are consistent with those with nonlinear method.
View Article and Find Full Text PDF

Download full-text PDF

Source
April 2002