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Hua Sun

Publications and source records attributed to Hua Sun.

26 records · Page 2Linked to original sources
PubMed2004

Induction of T-cell immunity against Epstein-Barr virus-associated tumors by means of adenovirally transduced dendritic cells.

BACKGROUND: Dendritic cells (DCs) are the most powerful antigen-presenting cells to induce specific T-cell immunity, which plays an important role in the body's anti-tumor responses. In this study, we assessed the feasibility and efficacy of inducing T-cell immunity against Epstein-Barr virus (EBV)-associated tumors in vivo using dendritic cells transfected with EBV latent membrane 2A (LMP2A) recombinant adenovirus. METHODS: Cytokine-activated bone marrow-derived DCs transfected with EBV LMP2A recombinant adenovirus were infused into BALB/c mice. Splenic cytotoxic T-cell responses were evaluated by cytotoxicity and interferon-gamma production assays. in vivo immune protection was then assessed in the mice tumor models implanted with tumor cells expressing EBV LMP2A. RESULTS: DCs transfected with EBV LMP2A recombinant adenovirus could strongly induce EBV LMP2A-specific cytotoxic T-cell responses and upregulate interferon-gamma production in vivo. Vaccination using these DCs led to prolongation of overall survival rates in the mice tumor models and retarded tumor growth. CONCLUSIONS: The results suggest that DCs transfected with EBV LMP2A recombinant adenovirus can serve as a feasible and effective tool for eliciting LMP2A-specific cytotoxic T-cell responses against EBV LMP2A in vivo in the treatment of EBV-associated tumors.

Adenoviridae↗
PubMed2004

[Maximum likelihood analysis for mapping dynamic trait QTL in outbred population. I . Methodology].

The quantitative traits whose phenotypic values change with time in life or other quantitative factors, were defined as dynamic traits. Based on the idea about random regression test-day model for estimating breeding values in animal evaluation, a mathematic model was constructed for mapping dynamic trait loci by using Legendre polynomials to model dynamic changes of each genetic effect. The Maximum likelihood analysis implemented via EM algorithm was used to estimate the parameters, including QTL position, fixed genetic regression effects for dynamic trait QTL mapping in outbred population. Compared with the existing method for dynamic trait mapping QTL, the new method presented here not only allowed to sample dynamic trait in disequillibrium way, but also can achieve to map dynamic traits QTL in any resource population by just one step. The further study on dynamic trait mapping QTL was theoretically discussed by incorporating genetic analysis of dynamic trait into general mapping QTL.

Likelihood Functions↗
PubMed2004

[Maximum likelihood analysis for mapping dynamic trait QTL in outbred population II. Simulation].

Based on the maximum likelihood analysis principle for dynamic trait QTL mapping, selecting three orders Legendre polynomial as sub-model,the effects of the individual number, the frequency of test day,the marker density and heritability on detecting power are investigated by Monte-Carlo simulation. Each factor is divided into three levels such as the high,middle and low,the combinations of which are arranged by using orthologal design. The simulating result shows that the high heritability needs less number of individuals and frequency of test day than the low one, but the number of individuals of more than 300 and the frequency of test day of 5% above can guarantee sufficient detecting power no matter what the heritability is like. The number of individuals has almost the same effect as the frequency of test day in dynamic traits QTL mapping and the number of individuals and the frequency of test day compensate each other under the same size of samples. As to the QTL detection for a dynamic point,simulation indicates that the presented dynamic trait QTL mapping method that focuses on the whole dynamic process is significantly superior to the classical mapping methods on each individual dynamic point.

Humans↗
PubMed2004

Isolation of Nanjing local strains of HHV-7 and their biological and immunological characteristics.

To investigate the biological and immunological characteristics of the Nanjing local strains of HHV-7, four strains of herpesvirus were isolated from saliva specimens of one healthy individual and three children suffering from a kidney disease in Nanjing. The viruses were identified by transmission electron microscopy (EM), indirect immunofluorescence assay (IFA) with a specific monoclonal antibody; nested polymerase chain reaction, restriction mapping and DNA sequencing. The virus-infected cells showed the typical cytophathic effect (CPE) under microscopy and could be detected by IFA with the human herpesvirus-7 (HHV-7) specific antibody. Under EM, herpesvirus-like and virions capsids could be found in their cytoplasm or nucleoplasm. HHV-7 DNA fragments amplified from infected cells by nested PCR were confirmed by restriction mapping and DNA sequencing. Similarly to DC strain, an known HHV-7 strain used in the present study as the positive control, the virus could be inactivated by ultraviolet irradiation for 10 min, heated at 45 centigrade degree for 30 min, pH<5 or>9 at 4 centigrade degree for 2 h and ether or chloroform for 10 h. The virus induced the production of TNF-alpha, IL-10 and IL-12 p 70 while inhibited IFN-alpha secretion, increased the percentage of CD2(+) cells while decreased that of CD4(+) or CD 45 RA(+) cells. The results indicate that the viruses isolated in Nanjing are HHV-7, which has similar biological characteristic to the known HHV-7 strain, DC. Infection with HHV-7 in vitro could affect immune function of lymphocytes by disturbing cytokine production and CD antigen expression.

Adult↗
PubMed2003

[Effects of one Chinese herbs on improving cognitive function and memory of Alzheimer's disease mouse models].

OBJECTIVE: To investigate Chinese herbs with the effect on significantly improving the cognitive function and retention of patients with Alzheimer's disease. METHOD: AD mouse models were established by injecting poly-beta-AP25-35 into the cerebral ventricle of mice. The curative effects of traditional Chinese herbs Dangguishaoyaosan, Chaihujialonggumulitang and two herbs (CHP I and CHP II) developed by the authors on improving the memory and cognitive function of AD mouse models were studied by the detection of behavioral and histochemical tests, with piracetam serving as control. RESULT: CHP II has profound curative effects on improving the memory and cognitive function of AD-like animal model. CONCLUSION: The present study indicates that it has a satisfactory prospect to seek new drugs from Chinese herbs to treat AD.

Acorus↗
PubMed2002

Effects of diacetyl guan-fu base A on pacemaker cells in sinoatrial node of rabbits.

AIM: To study the electrophysiological effects of diacetyl guan-fu base A (DGFA) on pacemaker cells in sinoatrial (SA) node. METHODS: Intracellular microelectrode method was used to record parameters of action potential (AP) in SA node of rabbits. RESULTS: DGFA could not only slow down spontaneous firing frequency (SFF), mean rate of repolarization (MRR), and rate of diastolic depolarization (RDD), but also prolong diastolic interval (DI) and duration of action potential (APD) in a concentration-dependent manner in SA node. Furthermore, DGFA markedly decreased the maximum rate of depolarization (MRD) with a slight reduce of the amplitude of action potential (APA) and there was no significant effect on the maximal diastolic potential (MDP). The decrease in SFF caused by DGFA was not affected by atropine (0.05 mg/L). CONCLUSION: The effects might be due to the reduction of calcium influx and potassium efflux, and the muscarinic receptors were not involved.

Action Potentials↗