Biomedical subjects

Qing-hua Zhang

Publications and source records attributed to Qing-hua Zhang.

12 recordsLinked to original sources

PubMed2006

[Gene expression profiling of diffuse-type gastric cancer by cDNA microarray].

OBJECTIVE: To identify cancer-related genes in diffuse-type gastric cancer and to explore its molecular mechanism by cDNA microarray analysis. METHODS: A total of 22 pairs of diffuse-type gastric cancer tissue and the corresponding normal mucosa were taken and freshly frozen. cDNA microarray with 14,592 genes/ESTs was used. Genes were considered to be up- or down-regulated when the fluorescent intensity ratio between tumor and normal mucosa was over 2-fold in over 50% of the samples (P < 0.05). Hierarchical clustering of regulated genes was performed as a measure to study expressional similarity. Validation of array results was carried out by real time quantitative PCR (QPCR). RESULTS: Compared with those of corresponding normal mucosa, there were a total of 153 genes/ESTs up-regulated and 204 down-regulated in diffuse-type gastric cancer. Hierarchical clustering demonstrated that the genes belonging to the same subgroup displayed similar function. Most of the overexpressed genes were those related to cell adhesion, cell motility, matrix reconstruction, cell proliferation and/or signal transduction; while genes related to defense response, toxicoid metabolism, DNA repairing, nuclear-cytoplasmic transport and/or anti-apoptosis made up the main list of the underexpressed genes. Seven genes showed higher expression in TNM (T I + T II) group than in (T III + T IV) group. QPCR confirmed the array analysis results. CONCLUSION: Gene expression profiling by cDNA microarray analysis provides not only molecular understanding of biological properties of cancer, but may also be helpful in discovering new diagnostic markers and therapeutic targets in gastric adenocarcinoma.

Adenocarcinoma↗

PubMed2006

[Study on the contamination status of butyltins in Taihu Lake].

Butyltins in surface water, sediments and biota samples from Taihu Lake were determined. The results show that butyltins content in most of the surface water samples is under the limit of the detection; five out of ten sediment samples are measured detectable butyltins. Monobutyltin (MBT) was the main species with the concentrations ranging from below the detection limits to 0.95 ng/g; while all biota samples were detected relatively higher butyltin concentrations with a range of 27.05 - 181.23 ng/g due to the obvious bioaccumulation. Tributyltin (TBT) was the main composition that occupied almost 70% of the total butyltins. The antifouling paints applied on the aquatic cultural box and boats was the possible main source of butyltin compounds in Taihu Lake.

China↗

PubMed2006

[Analyzing differentially expressed genes in the brain of rat exposed to mercury chloride using cDNA microarray].

This study is to determine differentially expressed genes in the brain of rat exposed to mercury chloride and investigate the molecular mechanism of mercury neurotoxicity using cDNA microarray. The experimental group of rats were treated with 0.5 mg/kg weight of mercury chloride via hypodermic injection. The differentially expressed genes in rat brains after I h of injection were scanned by the cDNA microarray. The gene expression profiles show that there are 742 genes, in which 562 are upregulated and 180 are downregulated. Further analysis by bioinformatic technique disclosed that the differentially expressed genes were involved in many biological processes, which included immuno-response and detoxifcation, transfer and expression of genetic information, cell signalling, neurotransduction, cell proliferation and cell differentiation, apoptosis, etc. The result of analysis indicated these genes might be related to the neurotoxicity of mercury. The investigation of differentially expressed genes using cDNA microarray provides a new approach to further disclose the neurotoxic mechanism of mercury.

Animals↗

PubMed2005

[Clinical effects of combination chemotherapy with irinotecan hydrochloride and cisplatin on cervical cancer: study of 46 patients].

OBJECTIVE: To evaluate the efficacy and toxicity of the combination chemotherapy of irinotecan hydrochloride plus cisplatin on cervical cancer. METHODS: Forty-six patients with cervical cancer, 43 with squamous cell carcinoma, 2 adenocarcinoma, and 1 small cell carcinoma, 41 being treated initially and 5 being recurrent cases of which 2 had undergone radiotherapy plus chemotherapy, 2 radical hysterectomy plus pelvic radiotherapy after operation, and 1 radical hysterectomy plus chemotherapy, aged 38 (22-61), were treated with irinotecan hydrochloride, 60 mg/m(2) in 250 ml normal saline administered on days 1, 8, and 15 by intravenous infusion over 60 min, plus cisplatin, 60 mg/m(2) in 500 ml 5% glucose given on day 1. This regimen was repeated every 28 days. Effectiveness evaluation was conducted after 1-2 courses for the initially treated patients and after 2-6 courses for the recurrent patients. RESULTS: Totally 79 courses of treatment were given to the 41 patients. After 1-2 courses 4 (9.8%) of the 41 stage Ib2-IIIb initially treated patients achieved complete remission, 30 (73.2%) achieved partial remission, and 7 (17.1%) remained at stationary phase with a overall effective rate of 82.9%. Of the 29 IIb and IIIb stage advanced patients who failed to receive operation originally 20 patients (69%) succeeded to be treated by radical hysterectomy after 1 to 2 courses when the tumorless space between the uterine and the pelvic wall > or = 3 cm with an operatibility rate of 69%. Of the 5 recurrent patients 1 case achieved complete remission, 2 partial remission, and 2 remained stable; none progression of disease was observed after 4-6 courses. The main toxic response and side effect included myelosuppression and diarrhea. CONCLUSION: Effective neoadjuvant chemotherapy on cervical cancer, combination therapy of irinotecan hydrochloride and cisplatin win opportunity for treatment and improves their life quality with tolerable side effects.

Adenocarcinoma↗

PubMed2005

[Rapid detection of rifampin resistance of Mycobacterium tuberculosis using high-throughput pyrosequencing technique].

OBJECTIVE: To develop a pyrosequencing approach to rapid detection of rifampin resistance in Mycobacterium tuberculosis based on characterization of all possible mutations in the 81 bp core region. METHODS: Two pyrosequencing sequencing primers and 1 pair of PCR primers were chosen for pyrosequencing analysis. The sensitivity of the pyrosequencing approach was determined by assaying PCR products generated from 10-fold serial dilutions of the DNA from Mycobacterium tuberculosis H(37) Rv strains. The efficacy of the pyrosequencing approach was evaluated by analyzing clinical Mycobacterium tuberculosis isolates with known antibiotic phenotypes. RESULTS: Rifampin resistance could be determined within 2 hours after PCR amplification and single-stranded template preparation by using only two pyrosequencing reactions. About 50 fg DNA/reaction was required in order to get sufficient PCR product for producing a long, clear and accurate pyrosequencing pattern. A total of 41 Mycobacterium tuberculosis isolates were tested and the results were concordant with those based on drug susceptibility testing and conventional DNA sequencing. CONCLUSION: The pyrosequencing technique is simple to perform and can be used as a rapid, high-throughput and efficient method for detecting rifampin resistance in Mycobacterium tuberculosis.

Antitubercular Agents↗

PubMed2005

[Construction of recombinant eukaryotic expression plasmid pcDNA3.1(+)-mtDNA of human colorectal carcinoma cells].

OBJECTIVE: To construct recombinant eukaryotic expression plasmid pcDNA3.1(+)-mtDNA for investigation of mutations in the D-loop region of mitochondrial DNA in human colorectal carcinoma. METHODS: The D-loop region of 3 colorectal carcinoma cell lines (SW480, LoVo, and HT29) were amplified by PCR and sequenced. The mtDNA fragment was recombined in the eukaryotic expression plasmid pcDNA3. 1(+), and the resultant pcDNA3.1(+)-mtDNA recombinant was used to infect murine fibroblast cell line NIH3T3. RESULTS: Among the 3 colorectal carcinoma cell lines (SW480, LoVo, HT29), 10, 9, 8 mutations, were identified, respectively. The 1119-bp fragment of mtDNA was successfully cloned. DNA sequencing analysis demonstrate total agreement of the sequence with that in GenBank. The mtDNA fragments were cloned into the multiple cloning sites of vector pcDNA3.1(+) properly and the recombinant was introduced into NIH3T3 cells. CONCLUSIONS: The D-loop region of mitochondrial DNA is a highly polymorphoric and mutable region with high mutation rate in human colorectal carcinoma cells. The recombinant eukaryotic expression plasmid pcDNA3.1(+)-mtDNA is successfully constructed.

Animals↗

PubMed2004

[Gene expression profile of yolk sac and fetal liver in mouse].

OBJECTIVE: To better understand the mechanisms of the fetal hematopoiesis turn over from primitive to definitive hematopoiesis through the expression level of c-kit(+) and sca-1(+), and major characters of gene expression profile of these cells. METHODS: c-kit and sca-1 expression level were monitored with fluorescence activated cell sorting (FACS) of the mononuclear cells from mouse yolk sac and fetal liver, while gene expression profile was carried out with EST sequencing strategy. RESULTS: The Sca-1(+) cells were increased while the c-kit(+) cells decreased with the embryonic development. Through profiling the functionally identified known genes, most of the highly expressed were globin genes, especially of embryonic types. CONCLUSION: The erythropoiesis played a key role in early fetal hematopoiesis in mammalian.

Animals↗

PubMed2004

Anti-rejection effect of ethanol extract of Poria cocos wolf in rats after cardiac allograft implantation.

BACKGROUND: A living fetus within the maternal uterus provides an example of allogene tolerance in mammals. Poria cocos Wolf is the main component of many Chinese medicinal combination drugs that have therapeutic effects on recurrent spontaneous abortion and that can maintain pregnancy until delivery. It was hypothesized that this herbal medicine can also prolong allograft survival after organ transplantation. Here, in an in vivo study, we report the anti-rejection effect of the ethanol extract of Poria cocos Wolf (EEPCW) in rats after cardiac allograft implantation. METHODS: Ten normal rats were healthy controls. Eighty rats receiving homologous heart transplants were divided into 4 groups of 20 rats each based on type of treatment: olive oil 8 ml.kg(-1).d(-1), EEPCW 25 mg.kg(-1).d(-1), EEPCW 50 mg.kg(-1).d(-1) or cyclosporin A 5 mg.kg(-1).d(-1). Allograft survival was observed in 10 rats from each group. On the seventh day post transplantation, pathological lesions and percentages of CD3+, CD4+, and CD8+ lymphocytes and the CD4+/CD8+ ratio in peripheral blood were assessed in another 10 rats from each group and in 10 normal rats. RESULTS: The survival time of donor hearts in the two EEPCW groups was significantly prolonged, to (15.9 +/- 2.4) days and (30.0 +/- 0.0) days, respectively, compared with (6.7 +/- 0.8) days in the control group. Pathological lesions in the two EEPCW groups were also less severe, and the percentages of CD3+, CD4+, and CD8+ lymphocytes and CD4+/CD8+ ratio were significantly lower in the EEPCW groups. CONCLUSIONS: Acute rejection of heart transplants and cellular immune reaction can be effectively suppressed using the EEPCW. Taking advantage of novel immunosuppressants derived from Chinese medicinal herbs used to treat abnormal pregnancy provides a hopeful road for future research and treatment in organ transplantation.

Animals↗

PubMed2004

[Establishment of CPP-SOM integrated cDNA microarray technology].

OBJECTIVE: To get an insight into the molecular mechanisms of diseases development and targeted therapy at the transcriptome level and search for potential therapeutic targets. METHODS: The present researchers established a cDNA microarray platform and applied component plane presentation integrated self-organizing map (CPP-SOM) to the microarray data obtained from a differentiation model, all trans retinoic acid-induced differentiation in NB4 cells. RESULTS: The platform included 12630 unique clones, including 9436 known genes. By CPP-SOM, the researchers were able to not only well classify the regulated genes into functionally distinct categories but also depict transcriptional changes throughout the process of the development of diseases or drug treatment. CONCLUSION: The platform has proven to be steady and reliable, and the CPP-SOM could serve as an important and good tool for analysis of microarray data.

Cell Line, Tumor↗

PubMed2003

[Cigarette smoking and Parkinson's disease: a population based case-control study].

OBJECTIVE: To explore the association with cigarette smoking for Parkinson's disease (PD). METHODS: One hundred and fourteen PD cases and 205 controls matched on gender and race were recruited from ongoing PD prevalence survey and identified at the neurological clinic of Peking Union Medical College Hospital. Face to face questionnaire interview was carried out and data on smoking and alcohol consumption were analyzed in a population-based case control study. RESULTS: With never-smokers as the reference category, we observed reduced risk for PD among ever smokers (OR = 0.49, 95% CI: 0.30 - 0.79) current smokers (OR = 0.44, 95% CI: 0.23 - 0.86) and ex-smokers (OR = 0.54, 95% CI: 0.30 - 0.96). When comparing with non-smokers, the ever smokers stratified by years of smoking had an inverse association with those whose smoking history longer than 20 years (OR = 0.35, 95% CI: 0.18 - 0.70) and an mild protective association with those who smoked less than 20 years (OR = 0.61, 95% CI: 0.35 - 1.07). Those who had quitted smoking for more than 20 years were less likely to have the disease than never smokers, and those who had quitted for less than 20 years were least likely to have PD. Those current smokers were still least likely to have the disease. Significant inverse gradient with pack-day smoker (trend P < 0.05), and the inverse association for cigarette smoking and PD were found not bing confounded by alcohol consumption. CONCLUSION: The inverse association between PD and cigarette smoking and history of cessation was found. Further studies need to provide biochemical evidence on the relation between smoking and its protective effect on PD.

Aged↗

PubMed2003

[Establishment of transgenic mice for HRX-EEN fusion gene].

OBJECTIVE: To study the biological function of fusion gene HRX-EEN and its role in leukemogenesis, and to provide an ideal animal model for anti-leukemia drug screening. METHODS: HRX-EEN fusion gene was constructed by use of three different DNA fragments, and it was inserted into hCG transgenic vector. G(0) transgenic mice were obtained by microinjection of the recombined DNA into the pronucleus of zygotes, followed by implantation of the injected zygotes into pseudopregnant mice. The integration of the transgene was tested by PCR and its expression by reverse transcription-polymerase chain reaction (RT-PCR). RESULTS: The sequence of recombined HRX-EEN gene was confirmed by sequencing. PCR testing revealed a total of 7 G(0) transgenic mice, these mice were then mated with C57 wild type mice. Except mouse No. 35 that died, the others all had their F1 offsprings. From these 6 lines of transgenic mice, HRX-EEN gene was found to be stably expressed in 3 lines by RT-PCR. Up to now, all transgenic mice expressing the fusion gene have no obvious abnormal phenotypes. CONCLUSION: A transgenic mice model in which the HRX-EEN fusion gene can be stably expressed has been established.

Animals↗

PubMed2003

[Clinical study of argon laser photocoagulation for central serous chorioretinopathy].

OBJECTIVE: To evaluate the clinical effect of argon laser photocoagulation for central serous chorioretinopthy. METHODS: This study included 102 consecutive cases of central serous chorioretinopathy (102 eyes) with fluorescein dye leakage located 500 microm away from the central fovea of the macula lutea as defined by fundus fluorescein angiography (FFA). Argon laser photocoagulation of the leakage spots was performed once (98 eyes) or twice (4 eyes) with the spot diameter for exposure ranging from 100 to 200 microm and exposure time of 0.2 s that delivered energy of 80 to 150 mW. RESULTS: The visual acuity was improved in 95 cases by one row on the standard vision chart within 2 or 3 d after the laser treatment, while in the other 7 cases, the visual acuity remained unchanged. The symptoms of micropsia, metamorphopsia and blurred vision disappeared in 87 cases. Serous detachment of the sensory retina and the fovea light reflex recovered in 80 cases within two weeks after the treatment and no fovea injuries due to photocoagulation were recorded. During the follow-up lasting for 6 to 12 months no recurrence or long-term complications in relation with photocoagulation treatment were observed in these cases. CONCLUSION: Argon laser photocoagulation is effective for central serous choiroretinopathy, and strict control of the photocoagulation conditions is crucial for preventing complications in relation to laser coagulation.

Adult↗