Biomedical subjects

Jian-Long Zhao

Publications and source records attributed to Jian-Long Zhao.

6 recordsLinked to original sources

PubMed2005

Monitoring microarray-based gene expression profile changes in hepatocellular carcinoma.

AIM: To find out key genes responsible for hepatocarcinogenesis and to further understand the underlying molecular mechanism through investigating the differential gene expression between human normal liver tissue and hepatocellular carcinoma (HCC). METHODS: DNA microarray was prepared by spotting PCR products of 1 000 human genes including 445 novel genes, 540 known genes as well as 12 positive (housekeeping) and 3 negative controls (plant gene) onto treated glass slides. cDNA probes were prepared by labeling normal liver tissue mRNA and cancer liver tissue mRNA with Cy3-dUTP and Cy5-dUTP separately through reverse transcription. The arrays were hybridized against the cDNA probe and the fluorescent signals were scanned. The data obtained from repeated experiments were analyzed. RESULTS: Among the 20 couple samples investigated (from cancerous liver tissue and normal liver tissue), 38 genes including 21 novel genes and 17 known genes exhibited different expressions. CONCLUSION: cDNA microarray technique is powerful to identify candidate target genes that may play important roles in human carcinogenesis. Further analysis of the obtained genes is helpful to understand the molecular changes in HCC progression and ultimately may lead to the identification of new targets for HCC diagnosis and intervention.

Carcinoma, Hepatocellular↗

PubMed2005

Study of MMLV RT- binding with DNA using surface plasmon resonance biosensor.

Surface plasmon resonance biosensor technique was used to study the binding of Moloney murine leukemia virus reverse transcriptase without RNase H domain (MMLV RT-) with DNA in the absence and in the presence of inhibitors. Different DNA substrates, including single-stranded DNA (ssDNA), DNA template-primer (T-P) duplex and gapped DNA, were immobilized on the biosensor chip surface using streptavidin-biotin, and MMLV RT(-)-DNA binding kinetics were analyzed by different models. MMLV RT-; could bind with ssDNA and the binding was involved in conformation change. MMLV RT-; binding DNA T-P duplex and gapped DNA could be analyzed using the simple 1:1 Langmuir model. The lack of RNase H domain reduced the affinity between MMLV RT-; and T-P duplex. The effects of RT inhibitors, including efavirenz, nevirapine and quercetin, on the interaction between MMLV RT-; and gapped DNA were analyzed according to recovered kinetics parameters. Efavirenz slightly interfered with the binding between RT and DNA and the affinity constant in the presence of the inhibitor (K(A) = 1.21 x 10(6) M(-1)) was lower than in the absence of the inhibitor (KA = 4.61 x 10(6) M(-1)). Nevirapine induced relatively tight binding between RT and DNA and the affinity constant in the presence of the inhibitor (K(A) = 1.47 x 10(7) M(-1)) was approximately three folds higher than without nevirapine, mainly due to rapid association and slow dissociation. Quercetin, a flavonoid originating from plant which has previously shown strong inhibition of the activity of RT, was found to have minimal effect on the RT-DNA binding.

Alkynes↗

PubMed2005

[Detection for single nucleotide polymorphisms].

As the third generation of genetic markers SNPs (single nucleotide polymorphisms) has been used extensively in gene mapping,disease-correlativity analysis ,population genetics and drug research. Here methods for detection are reviewed. Most SNP genotyping are a combination of method for interrogating SNPs and analysis technique.It described both parts and give a outlook for detection.

Fluorescence Polarization↗

PubMed2005

[The detection of plasmid pCAMBIA1301 in transgenic rice by arrayed primer extension].

Biochip technology which had emerged from the fusion of biotechnology and micro/nanofabrication technology at the end of 1980s has been widely used in life science, medicine, clinical diagnosis, drug development, agriculture, environmental protection and strategies. DNA microarray (also call gene chip, DNA chip), one kind of biochips, is small chip containing many oligonucleotide probes. It can hybridize with labelled sample, making it possible to detect large numbers of oligonucleotides at one time. So DNA microarray can overcome the disadvantage of traditional hybridization technology such as complexity, low automation, poor efficiency and quantity of molecules detected. This paper describes a new method to detect transgenic plant with gene chip. We have developed a novel arrayed-primer extension technique. It combines hybridization and PCR in one step, while ordinary DNA microarray needs two separate steps. Therefore our method provide a feasibility to detect long DNA fragment .

DNA Primers↗

PubMed2002

A signal process method for DNA segments separation in micro-channel electrophoresis.

This paper presents a signal process method for DNA segments separation in micro-channel electrophoresis. It is developed and optimized by using a laser induced fluorescence (LIF) based detection system. In this detection system, signal is sampled and processed through a novel signal process module. The results show that this signal process method provides good signal-to-noise ratios and lower limit of detection (LOD).

DNA↗

PubMed2002

Application of electromagnetic navigation in surgical treatment of intracranial tumors: analysis of 12 cases.

OBJECTIVE: To explore the application and characteristics of electromagnetic navigation in neurosurgical operation. METHODS: Neurosurgical operations with the assistance of electromagnetic navigation were performed in 12 patients with intracranial tumors. RESULTS: Total removal of the tumor was achieved in 8 cases, subtotal removal in 3 and removal of the majority of the tumor in 1 case. The error in the navigation averaged 1.9+/-0.9 mm and the time consumed by preoperative preparation was 19+/-2 min with the exception in 1 case. CONCLUSION: In comparison with optic navigation, electromagnetic navigation offers better convenience and absence of signal blockage, and with a head frame, automatic registration can be achieved.

Adult↗