Biomedical subjects
Publications and source records attributed to Jun-Ping Zhang.
C(60)H(36) was prepared by the Benkeser reaction with a much milder procedure. Thermal dehydrogenation of C(60)H(36) with IrCl(CO)(PPh(3))(2), Pd/C, and Ni-Al alloy and photochemical catalytic dehydrogenation with RhCl(CO)(PPh(3))(2) were studied. Pd/C catalyst was more effective for the thermal decomposition of C(60)H(36) till now.
BACKGROUND & OBJECTIVE: Radiofrequency (RF) can destroy local tumor tissue with less damage to the intervening tissue. The effect of RF on immune function of tumor-bearing body needs to be further investigated. This study was designed to evaluate the impact of RF on splenocyte immunity of mice bearing H22 liver cancer through detecting splenocyte proliferation, cytotoxicity, and expression pattern of cytokines T helper type 1 (Th1)/Th2. METHODS: A total of 24 BALB/c mice were randomized into 4 groups: RF, surgical resection, tumor-bearing control, and normal control groups. The proliferation of splenocytes was detected by MTT assay, and the cytotoxicity of splenocytes was assayed by double-color flow cytometry (FCM). The concentrations of interferon-gamma (IFN-gamma), interleukin-2 (IL-2), IL-4, and IL-10 in splenocyte culture supernatants were detected by enzyme-linked immunoabsorbent assay (ELISA), and mRNA levels of the cytokines in splenocytes were assayed by reverse transcription-polymerase chain reaction (RT-PCR). RESULTS: The proliferation of splenocytes and mortality of H22 cells were significantly higher in RF group than in surgical resection group, normal control group, and tumor-bearing group (P<0.05). The concentration and mRNA level of IL-2 and IFN-gamma were significantly higher in RF group than in surgical resection group, normal control group, and tumor-bearing group (P<0.05); the concentration and mRNA level of IL-4 and IL-10 were significantly lower in RF group than in surgical resection group, normal control group, and tumor-bearing group (P<0.05). No significant difference were found between surgical resection group and normal control group (P>0.05). CONCLUSIONS: RF can efficiently stimulate splenocyte activation and proliferation in H22-bearing mice, and enhance splenocyte cytotoxicity to tumor cells. RF could facilitate the secretion and gene transcription of Th1 type cytokines in H22 cells.
BACKGROUND & OBJECTIVE: Malignant glioma cells are resistant to most chemotherapeutic agents. Nitrosourea and temozolomide (TMZ) are main agents for treating malignant glioma. Resistance of malignant glioma to these agents is frequently associated with high levels of DNA repair protein O6-methylguanine-DNA methyltransferase (MGMT). This study was to evaluate the efficacy of individualized chemotherapy, according to chemotherapy sensitivity and resistance assays (CSRAs) and MGMT expression pattern, on malignant glioma, and observe the adverse events. METHODS: The pathologically confirmed malignant glioma patients, treated by operation at Cancer Center of Sun Yat-sen University from Dec. 2001 to Feb. 2006, were enrolled. The fresh tumor tissues obtained during operation were immediately sent for CSRAs using MTT assay. The expression of MGMT protein was detected by immunohistochemistry. After radiotherapy,the patients received chemotherapy according to the results of CSRAs and MGMT expression. The patients were evaluated for response to chemotherapy according to WHO criteria, and for toxicity according to National Cancer Institute (NCI) criteria. RESULTS: Forty-two patients were evaluated for response to chemotherapy. Seven patients received 2 chemotherapy regimens consecutively, therefore, overall 49 cases were evaluable. Of the 49 cases, 6 (12%) achieved complete remission (CR), 10 (20%) achieved partial remission (PR), 20 (41%) had stable disease (SD), and 13 (27%) had progressive disease (PD). The objective response rate (CR and PR) was 33%, and the disease control rate (CR, PR, and SD) was 73%. Hematologic toxicities were the main adverse events observed in this study, included grade IV anemia (1%), grade III-IV leukopenia (28%), and grade III-IV thrombocytopenia (8%). Non-hematologic toxicities mainly included nausea/vomit, fatigue, and alopecia. CONCLUSION: Individualized chemotherapy based on in vitro CSRAs and MGMT expression for patients with malignant glioma could improve overall response rate.
Clinical effect is of great importance to traditional Chinese medicine (TCM), and the rigorous and scientific methods for clinical effect assessment should be highly stressed in the clinical research of TCM. In this article, the authors analyzed the current status of the effect assessment of TCM and proposed some measures to improve the current effect assessment of TCM, in the hope of establishing an internationally accepted system of effect assessment reflecting the superiority and characteristics of TCM therapies.
Single nucleotide polymorphism (SNP) is the third generation genetic marker. SNP detection now is becoming increasingly important means in molecular diagnostics, clinical assay and novel drug development. It plays an essential role in drug resistance and anaphylactic reaction and has the importance in theoretical studies of gene location, hereditary diseases and human origin. With the accomplishment of human genome sequencing, the genotyping and discovering of SNP are becoming hot subjects in genetics and biomedicine researches. The methods for SNP detection were renewed rapidly and developed fast in past few years. In this review, several newly established detection methods including gene chip, molecular probe, fluorescence polarization and resonance, mass spectrometry, and bacterial magnetic particle are discussed. It could be expected that an accurate and sensitive, simple and easy-to-handle SNP technology with low cost and high throughput will be available on the basis of research breakthroughs of biochemistry, engineering and analytic software.
Cantharidin is a natural toxin that has antitumor properties and causes leukocytosis as well as increasing sensitivity of tumor cells resistant to other chemotherapeutic agents. There is limited information, however, on the molecular pharmacological mechanisms of cantharidin on human cancer cells. We have used cDNA microarrays to identify gene expression changes in HL-60 promyeloid leukemia cells exposed to cantharidin. Cantharidin-treated cells not only decreased expression of genes coding for proteins involved in DNA replication (e.g., DNA polymerase delta), DNA repair (e.g., FANCG, ERCC), energy metabolism (e.g., isocitrate dehydrogenase alpha, ADP/ATP translocase), but also decreased expression of genes coding for proteins that have oncogenic activity (e.g., c-myc, GTPase) or show tumor-specific expression (e.g., phosphatidylinositol 3-kinase). In contrast, these treated cells overexpressed several genes that encode intracellular and secreted growth-inhibitory proteins (e.g., BTG2, MCP-3) as well as proapoptotic genes (e.g., ATL-derived PMA-responsive peptide). Our findings suggest that alterations in specific genes functionally related to cell proliferation or apoptosis may be responsible for cantharidin-mediated cytotoxicity. We also found that exposure of HL-60 cells to cantharidin resulted in the decreased expression of multidrug resistance-associated protein genes (e.g., ABCA3, MOAT-B), suggesting that cantharidin may be used as an oncotherapy sensitizer, and the increased expression of genes in modulating cytokine production and inflammatory response (e.g., NFIL-3, N-formylpeptide receptor), which may partly explain the stimulating effects on leukocytosis. Our data provide new insight into the molecular mechanisms of cantharidin.
The theoretical possibility that exposure of a solid malignancy to high-intensity focused ultrasound (US), or HIFU, could lead to an increased rate of metastasis still remains. Using reverse transcriptase polymerase chain reaction (RT-PCR), the potential risk of hematogenous dissemination was assessed in HIFU-treated patients with solid malignancy. RT-PCR can demonstrate the presence or absence of specific RNA fragments. On the day before HIFU ablation, 5-mL peripheral blood samples were collected, and again 5 to 7 days after HIFU, from 26 enrolled patients (hepatocellular carcinoma, HCC: 10; osteosarcoma: 16). Total RNA was isolated and RT-PCR was performed to analyze the mRNA expression of (alpha-fetoprotein (AFP) and bone-specific alkaline phosphatase (BALP) genes. Positive AFP mRNA expression was preoperatively detected in 8 of 10 patients with HCC. In the postoperative specimens, positive expression was also detected in 8 of 10 patients. In 2 patients, circulating tumor cells were found preoperatively, but not postoperatively. Conversely, 2 patients with no circulating tumor cells preoperatively were found to have circulating tumor cells after HIFU. Of 16 osteosarcoma patients, 12 patients had circulating tumor cells and 4 had none. After HIFU treatment, 2 of the 12 patients had converted from presence to absence of circulating cells and the remaining 4 patients remained negative. It is concluded that patients undergoing complete HIFU ablation may demonstrate conversion from presence to absence of circulating tumor-specific marker mRNA, and that HIFU would not enhance the potential risk of metastasis in patients with malignant diseases.
AIM: To investigate the influence of esculentoside A (EsA) on immunological function and its mechanism of anti-inflammation. METHODS: Interleukin-1 production was measured by thymocyte co-stimulating assay; the radioactivity of [(3)H]arachidonic acid (AA) was used to evaluate the release of AA; prostaglandin E2 production was measured with radioimmunoassay (RIA); IL-2 and IFN-gamma were detected by ELISA method. RESULTS: EsA (3-12 micromol/L)could potently inhibit the production of IL-1 and PGE(2) from both silent and LPS induced macrophages. EsA had no significant effect on the release of AA from murine macrophages. EsA could inhibit the production of IL-2 from murine lymphocytes induced by ConA, but not affect the production from silent lymphocytes. EsA showed no effect on the production of IFN-gamma from both silent and ConA induced lymphocytes. CONCLUSION: EsA could affect the immunological function through inhibiting the production of IL-2 from activated splenocytes and the inhibition of production of IL-1 and PGE(2) might be one of the anti-inflammation mechanisms of EsA.
AIM: To investigate the influence of esculentoside A (EsA) on autoimmunity in mice and its possible mechanisms. METHODS: The level of anti-ds DNA antibody, proliferation of lymphoid cells, and inflammation by pathologic section of joint in mice were examined. The autoimmunity model is made through immunizing mice with formaldehyde treated Campylobacter jejuni strain CJ-S131 and Freund's complete adjuvant. The apoptosis of T cell was analyzed through morphology and flow cytometry (FACS). The expression of ICAM-1 mRNA in human umbilical vein endothelial cell line (ECV304) was determined by coupled reverse transcription and PCR amplification (RT-PCR). RESULTS: EsA could potently lower the level of anti-ds DNA antibody, inhibit the proliferation of lymphoid cells, and ameliorate inflammation in the joint of model mouse. The apoptosis of thymocyte activated by ConA was markedly accelerated while the expression of ICAM-1 mRNA in ECV304 was decreased by EsA. CONCLUSION: EsA has the positive curative effect on autoimmunity in a mouse model, which may function through inhibition of expression of ICAM-1 mRNA in ECV304 and acceleration of thymocyte apoptosis.