PubMed Health⌕ Search

Biomedical subjects

Ping Wang

Publications and source records attributed to Ping Wang.

At least 181 records · Page 10Linked to original sources
PubMed2005

Quinone methide derivatives: important intermediates to DNA alkylating and DNA cross-linking actions.

Induced DNA interstrand cross-links by chemical agents or photoactivation play very important roles for cancer therapy. Several important clinical drugs (e.g. cisplatin, psoralens, and mitomycin C) are known to induce DNA ISC formation, which can disrupt cell maintenance and replication. Among these anti-tumor agents, one mechanism was involved in quinone methide intermediate. Quinone methide derivative has played important roles in organic syntheses as well as in chemical and biological processes. This review is concerned with current efforts of quinone methide derivatives to DNA alkylation and DNA cross-links. The latest advances in this field will be reviewed in this article. The chemical and physical properties of quinone methide derivatives, the interactions between nucleobases and quinone methide derivatives, the reactions with phosphodiester, DNA alkylation and cross-link via quinone methide intermediate action will be discussed.

Alkylating Agents↗
PubMed2005

[Expression of NF-kappaB and COX-2 mRNA in rats with phlegm obstruction due to lung-deficiency].

OBJECTIVE: To study the role of nuclear factor-kappa B (NF-kappaB) and cycloxygenase-2 (COX-2) in the onset of phlegm obstruction due to lung-deficiency in rats and the therapeutic mechanism of Huatan Recipe. METHODS: Twenty-four SD rats were randomly divided into normal group, model group and treatment group, with 8 rats in each group. The rats in the model group and treatment group were exposed to sulfur dioxide and cold wind to establish the rat model of phlegm obstruction due to lung-deficiency, and the rats in the treatment group were also treated with Huatan Recipe, a compound traditional Chinese medicine. The expression of NF-kappaB in the bronchial epithelial cells of the rats was tested with the method of immunohistochemistry, and the COX-2 mRNA in the lung tissues of the rats was measured by using reverse transcription-polymerase chain reaction. RESULTS: The expressions of NF-kappaB and COX-2 mRNA in rats of the model group were higher than those of the normal group (P<0.01), and the expressions of NF-kappaB and COX-2 mRNA in rats of the treatment group were obviously lower than those of the model group (P<0.01). CONCLUSION: The NF-kappaB and COX-2 play an important role in the onset of phlegm obstruction in rats. Huatan Recipe may prevent the development of phlegm obstruction by down-regulating the expressions of NF-kappaB and COX-2 mRNA.

Animals↗
PubMed2005

[Preparation of specific monoclonal antibody against nucleocapsid protein of SARS coronavirus].

AIM: To express nucleocapsid(N) protein of SARS coronavirus and produce monoclonal antibody(mAb) to N protein. METHODS: N protein gene was amplified by RT-PCR. After being confirmed by DNA sequencing, the gene was subcloned into prokaryotic expression vector. N protein expressed in E.coli was recovered from SDS-PAGE gel and served as immunogen in the preparation of the mAb. RESULTS: DNA sequencing confirmed that the amplified fragment was N protein gene. SDS-PAGE analysis showed that the M(r) of the expressed protein was approximately 43 kd. This expressed protein could be further confirmed in Western blot by using serum from a convalescent SARS patient as primary antibody. Western blot analysis proved that three mAbs obtained could react specifically to the recombinant N protein. CONCLUSION: The prepared recombinant N protein and mAbs against N protein lay the foundation for further development of early diagnosis assays for SARS coronavirus infection.

Animals↗
PubMed2005

[Recombinant adeno-associated virus carrying hepatitis B virus C gene (rAAV-HBV-C) effectively pulses dendritic cells (DC) without affecting their maturity].

OBJECTIVE: Recombinant virus pulsated dendritic cells (DCs) may affect their survival, growth and maturity. This study is to test the infection efficiency of recombinant adeno-associated virus carrying hepatitis B core antigen (rAAV-HBV-c) to DCs and the growth and maturity of them. METHODS: Peripheral blood mononuclear cells (PBMCs) were isolated from healthy blood donors. Adherent monocytes were pulsed by rAAV-HBV-c and 293 lysate as controls on the first day of isolation. DCs were cultivated in AIM-V media with 1000 u/ml granulocyte macrophage stimulating factor (GM-CSF), 1000 u/ml interleukin-4 (IL-4) and 50 ng/ml tumor necrosis factor-alpha (TNFalpha) separately in vitro. DCs were examined at different times and the expressions of several clusters of differentiations (HLADR, CD14, CD80, CD83, CD86) were studied using FACS after being cultured for 7 days. The transcription and expression of HBV-C gene were analyzed by reverse transcription-polymerase chain reaction (RT-PCR) and intracellular staining fluorescence activated cell sorter (FACS), respectively. RESULTS: The rAAV-HBV-c infected and uninfected monocytes gradually matured and their morphology had no significant differences. The CDs expressed on the surfaces of the two groups of DCs were also similar (HLADR: 96.1% vs. 94.5%; CD86: 87.7% vs. 89.8%; CD83: 75.6% vs. 78%; CD80: 52% vs. 54.3%; CD14: 6.4% vs. 4.5%). HBV-C gene mRNA expression was measured using RT-PCR and 89.5% of the rAAV-HBV-c infected DCs showed their protein expression using FACS. CONCLUSION: rAAV-HBV-c can effectively pulse DCs without affecting the growth and maturity of them.

Cells, Cultured↗
PubMed2005

Correlation of polymorphism in the interleukin-1 receptor antagonist gene intron 2 with alcoholic liver disease.

BACKGROUND: Interleukin-1 receptor antagonist (IL-1ra) can inhibit the pro-inflammatory effects of IL-1, which recently has been thought to involve the pathogenesis of alcoholic liver disease (ALD). This study was undertaken to determine whether there is any association between IL-1ra gene polymorphism and ALD in a Chinese population. METHODS: The polymorphism of IL-1ra gene intron 2 (VNTR) was assessed in 165 alcoholics (43 alcohol-dependent subjects without liver diseases, 30 patients with alcoholic fatty liver, 61 patients with alcoholic hepatitis and 31 patients with alcoholic cirrhosis) and 65 healthy control subjects by PCR with DNA of peripheral blood mononuclear cells. RESULTS: The rate of IL-1RN*1 carriage was statistically higher in the alcoholics than in the control group (98.79% vs 93.85%, chi2=4.48, P<0.050). And the IL-1RN*1 allele frequency was more common in the alcoholics than in the control group (86.67% vs 76.92%, chi2=6.56, P<0.025). IL-1RN*1 heterozygote was significantly more frequent in the patients with alcoholic hepatitis or those with cirrhosis than in the alcohol-dependent subjects without liver diseases (32.79%, 29.03% vs 9.30%; chi2=7.84, chi2=4.84; P<0.010, P<0.050). The IL-1RN*2 allele frequency in the patients with alcoholic hepatitis and the patients with cirrhosis was also significantly higher than in those alcoholics without liver diseases (13.93%, 17.74% vs 4.65%; chi2=4.79, chi2=6.78; P<0.050, P<0.010). But the frequencies of IL-1RN*1 heterozygote and IL-1RN*2 allele appear to be not different between the patients with alcoholic fatty liver and the alcoholics without liver diseases. CONCLUSIONS: IL-1ra gene polymorphism is closely associated with race. IL-1RN*2 allele doesn't influence the susceptibility to ALD, but the gene carriers with ALD have additional risk for aggravation of the illness.

Adult↗
PubMed2005

[Binding and inhibition of adeno-associated virus Rep78 protein with hepatitis B virus C promoter].

OBJECTIVES: Adeno-associated virus (AAV) Rep78 is known for its inhibitory effects on replication of several viruses and oncogenes transformations. The study was to investigate the effect of Rep78 on hepatitis B virus C (HBV-C) gene and the mechanism of it. METHODS: HBV-C promoter and HBV-C gene with its promoter were amplified by PCR and labeled with 32P-ATP. Electrophoretic mobility shift assay (EMSA) and in vitro transcription were utilized to detect the binding of MBP-Rep78 with HBV-C promoter and the transcription of HBV-C gene. RESULTS: EMSA showed that by increasing the amount of Rep78 protein from 0.1 microg to 1.0 microg, the binding bands got stronger in a dose-dependent manner. In addition, Rep78 antibody was used to certify the specificity of this binding. The compound of Rep78, Rep78 antibody and HBV-C promoter were seen as super shift bands in EMSA. Meanwhile, HBV-C gene transcription was significantly inhibited by in vitro transcription which meant that Rep78 could not only bind with HBV-C promoter, but also could inhibit the transcription of HBV-C gene. CONCLUSION: AAV Rep78 could inhibit the transcription of HBV-C gene through its binding with HBV-C promoter.

DNA-Binding Proteins↗
PubMed2005

[A study on etiology and pathogenic mechanism of decompression sickness].

OBJECTIVE: To explain the etiology of decompression sickness (DCS) and to elucidate its pathogenic mechanism. METHOD: Tunica conjunctiva was examined by microscopy and blood pressure was measured at the exposed femoral arteries in inadequately decompressed animals after hyperbaric exposure. Then pathological examinations were done. RESULT: Animals with vascular spasm and dysfunction after decompression showed DCS symptoms. Severe DCS was found in the period of increasing of blood pressure swelling. Appeared in endothelial cells, fracted, hemorrhages were also formed in the body of DCS animals. CONCLUSION: DCS is a disease with vascular spasm and dysfunction caused by decompression. It's resulted from anoxia or pathological change caused by vascular spasm, dysfunction or even failure of blood vessels due to the gas tension (etiology) provoked by supersaturated gas in the blood during descending of ambient pressure. Vascular spasm and dysfunction impede the elimination of gas from the blood, and once the gas amount is sufficient to cause severe ischemia of the circulation system, the state of disease would be severe.

Animals↗
PubMed2005

[Individualized energy metabolic monitoring and its clinical application].

The nutritional status affects the factors of patient outcome such as the therapeutic intervention, the length of hospitalization and prognosis. Personalization of nutritional support treatments can minimize the complications that may arise from overfeeding and underfeeding. Appropriate nutritional support requires an individual nutrition assessment based on each patient's caloric and regularly monitored respiratory quotient to accommodate continuing changes in the patient's condition.

Basal Metabolism↗
PubMed2005

[Comparison of therapeutical effect between arterial interventional chemotherapy and venous chemotherapy on bulky or locally advanced cervical cancer].

OBJECTIVE: To investigate the therapeutical effect of arterial interventional chemotherapy and venous chemotherapy on bulky or locally advanced cervical cancer. METHODS: A retrospective study was carried out on 174 patients with bulky or locally advanced cervical cancers admitted to our hospital from Sept 1997 to Sept 2003. The therapeutical, toxic and adverse effects of either arterial interventional or venous chemotherapy were analyzed and compared. RESULTS: Among those 174 patients, 69 were given arterial interventional chemotherapy. Patients with cervical adenocarcinoma received cisplatin, fluorouracil, mitomycin C, and patients with squamous carcinoma of cervix were treated with bleomycin, cisplatin. The effective rate was 81%, and the rate of surgery after chemotherapy was 67%. While in the venous chemotherapy group, 105 patients were treated with the same chemotherapeutical schemes and doses as in arterial interventional chemotherapy group. The effective rate was 83% and the rate of surgery after chemotherapy was 70%. The differences between these two groups showed no significance (P > 0.05). No intolerable toxic and adverse effects were noticed during neoadjuvant chemotherapy. The 3- and 5-year survival rates of arterial interventional chemotherapy group were 76%, 70% respectively, and those of venous chemotherapy group were 78%, 71% respectively, without significant difference (P > 0.05). CONCLUSIONS: Neoadjuvant chemotherapy is a safe and effective means for treating patients with bulky or locally advanced cervical cancer. The therapeutical effects of venous and arterial interventional chemotherapy are similar. And no intolerable toxic and adverse effects were noticed during neoadjuvant chemotherapy. Venous administration is easy and inexpensive and less demanding for special equipment. It shows promising prospect in clinical application.

Adult↗
PubMed2005

[Perform analyse on the predictive model of ischemic cardiovascular diseases in Qingdao].

OBJECTIVE: To explore the clinical usage of the methods and tools of the 10-year's risk estimation of ischemic cardiovascular disease (ICVD) in Chinese. METHODS: The risk of ICVD in 2287 middle-aged Qingdao people was evaluated by the methods and tools of the 10-year's risk estimation of ICVD in Chinese, which was developed by Cardiovascular Institute, Chinese Academy of Medical Sciences. RESULTS: (1) 98.16% of male and 99.39% of female had a 10-year absolute risk of ICVD less than 10%. 0.19% of male and 0.15% of female had a 10-year absolute risk of ICVD higher than 20%. (2) In the low risk group (absolute risk < 10%) detection rate of abnormal SBP, FBG, TC, BMI was 100%, 20.8%, 75%, 87.5% respectively. While in the high risk group (absolute risk > or = 20%) detection rate of abnormal SBP, FBG, TC, BMI was 7.31%, 3.4%, 37.74%, 59.26% respectively. CONCLUSIONS: The prediction models and simplified tools for estimating 10-year-risk of ICVD in Chinese can predict satisfactorily the occurrence of cardiovascular disease in Qingdao area.

Adult↗
PubMed2005

[MEKK2 regulates the production of interleukin 2].

OBJECTIVE: To study the role of MEKK2 on the production of IL-2 in Jurkat cells stimulated by PHA/anti-CD28 antibody. METHODS: The MEKK2 and JNK kinase activities were measured in both dominant negative MEKK2 Jurkat (dnMEKK2 Jurkat) cells and parental Jurkat cells. The AP(1) and IL-2 promotor activities were measured by luciferase activity assay. The IL-2 mRNA and protein were detected by RT-PCR and Western blot. RESULTS: After stimulation by PHA/anti-CD28, JNK was activated in parental Jurkat cells but not in dnMEKK2 Jurkat cells. The luciferase report gene activities of AP1 and IL-2 promotors were increased by 4- and 5-folds in parental cells whereas only by 1 fold in dnMEKK2 Jurkat cells. The level of IL-2 mRNA and IL-2 protein were increased in parental Jurkat cells but not in dnMEKK2 Jurkat cells. CONCLUSION: MEKK2 plays an important role on the production of IL-2 in Jurkat cell stimulated with PHA/anti-CD28 antibody. It is a potential drug target for the treatment of GVHD and autoimmune disease.

Humans↗
PubMed2005

[Experimental study on mechanism of recompression therapy of decompression sickness].

OBJECTIVE: To elucidate that recompression is the most efficient measure in removing the pathogenic factors. METHOD: When rabbits were suffering from severe DCS, their pressure were immediately compressed to 0.5 Mpa. Precordial region was monitored continuously with a Doppler flow meter, micrography of the bulbar conjunctiva was done intermittently and the behaviors of the animals were recorded. RESULT: Effects of therapeutic recompression and elimination of circulating bubbles were correlated to rate and extent of recovery of microvascular function. The animals' DCS with severe dysfunction or failure of blood vessels, DCS became worse owing to progressive impairment of microvascular function during recompression and decompression. CONCLUSION: The pressure could only cancel the tension provoked by supersaturated gas in the blood so as to relieve the spasm of the compensatory blood vessels, which can restore the blood circulation and reverse the developing course of the DCS. The pressure, however, couldn't recover the function of the blood vessels with severe dysfunction or failure, or repair the injured tissues, or eliminate the circulating bubbles directly.

Air Pressure↗
PubMed2005

[Regulatory effects of ammonium ions on the biosynthesis of meilingmycin].

Based on the effects of different ammonium sulfate concentrations on meilingmycin biosynthesis, the results show that lower concentration of ammonium ions stimulates the biosynthesis of meilingmycin, while the concentration of higher than 5mmol/L inhibits the mycelial growth and the biosynthesis of the products. However, the sugar consumption rate increases with the elevating concentration of ammonium sulfate. On this basis, six enzymes, which are greatly related to the meilingmycin biosynthesis and the glucose metabolism, were measured and analyzed during the meilingmycin fermentation process. The results suggest that glucose-6-phosphate dehydrogenase, citrate synthase, succinate dehydrogenase and fatty acid synthase are stimulated by higher concentration of ammonium ions, while valine dehydrogenase and methylmalonyl-CoA carboxyltransferase are inhibited. From the results it follows that ammonium ions favors primary metabolism, that is, the HMP passway and the TCA circle is enhanced, as well as the source of the precursors for the biosynthesis of meilingmycin is restricted, which bring about the lower production of meilingmycin.

Ammonium Sulfate↗
PubMed2005

[Determination of nerolidol in volatile oil of Dalbergia odorifera by GC].

OBJECTIVE: To develop a method for determination of nerolidol in the volatile oil of Dalbergia odorifera. METHOD: GC method was used. The samples were separated on Agilent HP-5 column (320 microm x 30 m, 0.25 microm) with the mobile phase of highly pure N2. Flow rate was 2 mL x min(-1). RESULT: Linearity of nemlidol was good linearity in the range of 0.059-1.97 mg x mL(-1), and the average recovery was 97.5%, RSD 2.3%. CONCLUSION: This method is simple, accurate, rapid and reproducible.

Chromatography, Gas↗
PubMed2005

[Tissue engineering of dentin-pulp complex-like structures by human dental mesenchymal cells].

OBJECTIVE: To establish three-dimensional culture model of human dental mesenchymal cells and bioengineer in vivo with ceramic bovine bone (CBB) and Collagraft as scaffolds. METHODS: Human dental mesenchymal cells induced upon stimulation of bFGF and IGF-1 or TGF-beta(1) were implanted onto CBB and Collagraft containing the same kinds of growth factors respectively. Then cell/scaffold constructs were transplanted into nude mice to establish in vivo culture model of dental mesenchymal cells. Control groups were set up at the same time. After 4 weeks or 10 weeks, the implants were taken out for histological and immunohistochemical analysis. RESULTS: Within 10-week implant tissues, typical dentin-pulp complex-like structures were generated in scaffolds containing growth factors. Human dentin sialoprotein (DSP) was expressed in the newly formed dentin. This phenomenon wasn't observed in control groups and 4-week implants. CONCLUSIONS: Dentin-pulp complex-like structures could be bioengineered successfully with human dental mesenchymal cells and CBB or Collagrafts containing growth factors in nude mice.

Animals↗
PubMed2005

[Clinical research of heart rate turbulence on predictive value in patients with acute myocardial infarction].

OBJECTIVE: To assess the predictive value of heart rate turbulence (HRT) in patients with acute myocardial infarction. METHODS: One hundred and twenty-five patients with acute myocardial infarction were enrolled in this study. During the period from 6 to 21 days after onset of acute myocardial infarction, they were undergone 24-hour Holter recordings to collect the mean RR interval and heart rate variability (HRV) SDNN. The Holter files were processed with software of "HRT! View V0.60-1" to obtain the value of Turbulence Onset (TO) and Turbulence Slope (TS) and the value of "heart rate variability (HRV) SDNN". LVEF and EDD were measured by Ultrasonic Cardiography. Endpoint of follow-up was cardiac death. According to the results, patients were divided into two groups (the "survivors" and the "nonsurvivors"). The predictive value for high-risk patients with acute myocardial infarction was assessed by variables between the two groups. RESULTS: In the period of follow-up (mean 225.4 +/- 99.8 days), 14 patients died and 111 patients survived. In the univariate Cox regression analysis, "TS" was a strong univariate predictor of mortality (hazard ratio 11.46, P < 0.01); "TO" was a relatively weak predictor and the hazard ratio was 2.76 (P > 0.05). Combination of abnormal TO and abnormal TS was the strongest mortality predictor (hazard ratio 26.70, P < 0.01); in the multivariate Cox regression analysis, TS < or = 2.5 ms/RR and EDD > or = 5.6 cm were the independent predictors of mortality with hazard ratios 9.49 (P < 0.01) and 3.64 (P < 0.05), respectively. CONCLUSIONS: The absence of the heart rate turbulence after ventricular premature beats is a very potent post-infarction risk predictor which is independent of and stronger than other known risk predictors.

Aged↗