Biomedical subjects

Xi-Ran Zhang

Publications and source records attributed to Xi-Ran Zhang.

11 recordsLinked to original sources

PubMed2006

[Inhibitory effect of iguratimod on TNFalpha production and NF-kappaB activity in LPS-stimulated rat alveolar macrophage cell line].

AIM: To investigate the effect of iguratimod (T-614), a non-steroidal anti-inflammatory drug, on TNFalpha mRNA expression and TNFalpha production, and on the activity of nuclear factor-kappaB (NF-kappaB) in the rat alveolar macrophage cell line (NR8383) activated by LPS. METHODS: NR8383 cells were pretreated with T-614 (13.4, 26.7, 53.4 micromol x L(-1)), then were stimulated with LPS. The production of TNFalpha in the supernatant of NR8383 was assayed by enzyme-linked immunosorbent assay (ELISA). The TNFalpha mRNA level was determined by a semi-quantitative PCR assay. Assessment of the NF-kappaB DNA binding activity was performed by an ELISA kit. RESULTS: T-614 inhibited LPS-stimulated mRNA expression and production of TNFalpha in a concentration-dependent manner, as well as the activity of NF-kappaB. The IC50 value of effect of T-614 on TNFalpha level was 26.2 micromol x L(-1). CONCLUSION: The inhibitory effect of T-614 on the production of TNFalpha in LPS-stimulated NR8383 cells may be mediated by suppression of NF-kappaB activity.

Animals↗

PubMed2005

[Phylogenetic relationship between tufted deer(Elaphodus cephalophus) and Muntiacus deer is revealed by the exon and intron of K+ channel gene].

In this study, partial fragments of potassium ion channel gene were amplified using the genomic DNA of muntjak, reevesi, crinifrons, and Elaphodus cephalophus. The PCR products were ligated to the plasmid of pMD18-T Vector by the method of direct T-A cloning. The positive clones were identified by colony PCR. The sequences of the recombinant clones were determined using M13-47/RV-M universal primers and aligned by the software CLUSTALW. The nucleotide divergences of exon were 0.90%-1.44% among three species of Muntiacus, 0.90%-1.26% between E. cephalophus and each of Muntiacus deer. In the nucleotide of intron there is 0%-1.22% difference among these muntjac deers, and the divergene reached about 1.83% between E. cephalophus and the three species of Muntiacus. Using the software of MEGA to analyse molecular phylogeny, Phylogenetic trees were constructed with neighbor-joining method and maximum parsimony method. The result showed Muntiacus, crinifrons is most closely related to muntjak, with reevesi as their sister species. E. cephalophus is in the other genus.

Animals↗

PubMed2005

RTN4-C gene expression in hepatocellular carcinoma and its influence on SMMC7721 cell growth and apoptosis.

RTN4-C gene is a member of RTNs. To investigate its expression in human hepatocellular carcinoma tissues and study its function on SMMC7721 cells, RT-PCR was conducted to detect its expressions in human hepatocellular carcinoma tissues. RTN4-C-pcDNA3. 1 plasmid was reconstructed and stably transfected into SMMC7721 cells by Lipofect AMINE. Growth curve of SMMC7721 measured by MTT and apoptosis indentified with acridine orange staining were examined to demonstrate the effect of RTN4-C on SMMC7721. Immunocytochemical analysis for mutant p53, c-Fos, Hsp70 proteins were conducted. The results showed that the transfected SMMC7721 cells grew more slowly than control and the average inhibition rate at the 1st, 2nd and 3rd day were 33.8% +/- 0.026, 56.2% +/- 0. 094, 34.8% +/- 0.077 respectively. In transfected SMMC7721 cell line, the apoptosis was strengthened,mutant p53 protein tranferred from nucleus to cytoplasm and c-Fos, Hsp70 proteins were decreased. Our data indicated RTN4-C gene was expressed differently in hepatocellular carcinoma and its paracancerous tissues. By tranferring mutant p53 protein from nucleus to cytoplasm and decreasing c-Fos, Hsp70 protein expression, RTN4-C inhibited SMMC7721 cells growth and promoted its apoptosis.

Adult↗

PubMed2004

Spatiotemporal pattern of calmodulin and [Ca2+]i is related to resumption of meiosis in mouse oocytes.

During meiotic maturation, mammalian oocytes undergo a series of morphological and physiological changes that prepare them for fertilization. Calcium-initiated signaling is thought to trigger these processes. In this study, we examine the spatio-temporal pattern of calcium and calmodulin (CaM), its downstream receptor, in order to investigate their association with meiotic maturation. Intracellular free calcium and activated CaM levels were measured using the fluorescent probes Calcium Green-1 and TA-CaM, respectively. The distribution patterns were examined using confocal microscopy. Both calcium and activated CaM showed a dynamic spatiotemporal distribution during meiotic maturation. After release from IBMX buffer, calcium was found to periodically translocate from the perinuclear region to the germinal vesicle (GV) in 90 s intervals. After 90 min, calcium stopped oscillating and became concentrated within the GV. After a further 60 min, the GV broke down and calcium dispersed into the ooplasm, but calcium levels were slightly lower here than in the original nuclear region. Activated CaM also showed a dynamic patterning process similar to calcium. Taking the data from calcium chelation and CaM inhibition together, our results suggest that the dynamic distribution patterns of calcium and activated CaM are crucial for oocyte maturation.

Animals↗

PubMed2004

Down regulation of DRET gene in human hepatocellular carcinoma tissues samples from Qidong area, China.

OBJECTIVE: To analyze the expression of DRET gene in hepatocellular carcinomas (HCCs) tissue specimens in comparison with normal liver tissue to evaluate the relationship between DRET gene and HCC. METHODS: 250 primary HCCs and 50 normal liver tissue samples from Qidong area, China, were studied for DRET mRNA and protein expression with the use of Northern blot analysis, in situ hybridization and immunohistochemistry. RESULTS: By Northern analysis, moderate to strong DRET mRNA expression was present in normal liver samples. In contrast, DRET mRNA expression in tissue samples of primary HCCs was markedly decreased compared with normal controls. Primary HCCs that gave rise to metastasis showed significantly lower DRET mRNA levels than nonmetastasizing HCCs. By in situ hybridization analysis, nonmetastatic HCCs samples didn't differ from controls. In contrast, most of the primary metastasizing HCC showed only faint or moderate DRET mRNA expression. Tissue sections of nonmetastatic HCC exhibited lower DRET immunoreactivity than control samples, but higher labeling index than metastatic HCC samples. CONCLUSIONS: Expression of DRET on mRNA and protein levels in HCC cells is related to HCC metastatic ability.

Carcinoma, Hepatocellular↗

PubMed2004

[Cloning of ZFY /ZFX gene of the tufted deer and identification of its sex].

According to the human sex differentiation related ZFY and ZFX genes, a pair of primers were designed , and fragments were amplified from the genomic DNA of male or female tufted deer. Subsequently the amplified fragments were cloned into the vector pMD18T and were sequenced. It is found that the sequences of ZFY gene and ZFX gene have 91% homology. Based on the different nucleotides, restriction site of Ava II was found to be specific to ZFX gene. The results show that the combination of PCR with Ava II digestion is a simple and sensitive way to identify the tufted deer sex.

Amino Acid Sequence↗

PubMed2003

Codon 249 mutation in exon 7 of p53 gene in plasma DNA: maybe a new early diagnostic marker of hepatocellular carcinoma in Qidong risk area, China.

AIM: One of the characteristics of hepatocellular carcinoma (HCC) in Qidong area is the selective mutation resulting in a serine substitution at codon 249 of the p53 gene (1, 20), and it has been identified as a "hotspot" mutation in heptocellular carcinomas occurring in populations exposed to aflatoxin and with high prevalence of hepatitis B virus carriers (2,3,9, 10,16,24). We evaluated in this paper whether this "hotspot" mutation could be detected in cell-free DNA circulating in plasma of patients with hepatocellular carcinoma and cirrhosis in Qidong, China, and tried to illustrate the significance of the detection of this molecular biomarker. METHODS: We collected blood samples from 25 hepatocellular carcinoma patients, 20 cirrhotic patients and 30 healthy controls in Qidong area. DNA was extracted and purified from 200 microl of plasma from each sample. The 249(Ser) p53 mutation was detected by restriction digestion analysis and direct sequencing of exon-7 PCR products. RESULTS: We found in exon 7 of p53 gene G-T transversion at the third base of codon 249 resulting 249(Arg) - 249(Ser) mutation in 10/25 (40 %) hepatocellular carcinoma cases, 4/20 (20 %) cirrhotics, and 2/30 (7 %) healthy controls. The adjusted odds ratio for having the mutation was 22.1(95 % CI, 3.2-91.7) for HCC cases compared to controls. CONCLUSION: These data show that the 249(Ser) p53 mutation in plasma is strongly associated with hepatocellular carcinoma in Qidong patients. We found this mutation was also detected, although it was at a much lower frequency, in plasma DNA of Qidong cirrhotics and healthy controls; We consider that these findings, together with the usual method of HCC diagnosis, will give more information in early diagnosis of HCC, and 249(Ser) p53 mutation should be developed to a new early diagnostic marker for HCC.

Adult↗

PubMed2003

The relationship between metallothionein-1F (MT1F) gene and hepatocellular carcinoma.

To investigate the expression of MT1F gene in hepatocellular carcinoma tissue and the growth suppression effect of exogenous introduction of MT1F gene on liver cell line HepG2 and to explore the potential application of MT1F gene in gene therapy of tumor. Eukaryotic expression vector of pCMV-MT1F plasmid was introduced into HepG2 line which expressed no MT1F protein originally with lipofectamine transfection method. The cell growth curve, soft agar colony formation rate and tumorigenicity in SCID mice were examined to demonstrate the growth suppression effect of exogenous MT1F gene on HepG2 cell line. The MT1F mRNA and MT1F protein were also detected in 60 pairs of surgical specimens of hepatocellular carcinoma by in situ hybridization and immunohistochemistry. The transfected HepG2 cell line grew more slowly than control HepG2 as shown by cell growth curves, the soft agar colony formation rate (3.8 percent vs. 7.4 percent, p <.01) and the average growth rate of tumor in SCID mice (30.9 +/- 6.9 vs. 70.3 +/- 5.6, p <.01). The expression level of MT1F mRNA and protein significantly increased in paracancerous tissue, normal tissue than in cancer tissues (75 percent, 70 percent vs. 16.7 percent by ISH and 66.7 percent, 60 percent vs. 10 percent by IHC, p <.01). Exogenous MT1F gene shows the strong effect of growth inhibition on HepG2 cell line. In the liver cancer tissue, MT1F shows down-regulated expression that supports the inhibited function of MT1F in cancer growth and suggests MT1F may have an important role in gene therapy of hepatocellular carcinoma.

Animals↗

PubMed2002

[Preliminary study on hens immunized with recombinant human testis prostaglandin D synthase DNA].

OBJECTIVES: In order to identify whether the hens immunized with recombinant human testis prostaglandin D synthase (rhtL-PGDS) DNA can produce anti-L-PGDS antibody. METHODS: The serum were got from the hens immunized with recombinant plasmid pGEX-2T/htL-PGDS DNA (100 micrograms) every 2 weeks for 2 times. The exist of anti-L-PGDS antibody and its titer were tested with agarose dual immunodiffusion and ELISA with rhtL-PGDS as antigen. RESULTS: The serum anti-L-PGDS antibody in hen immunized with pGEX-2T/htL-PGDS DNA were confirmed and its titer tested by ELISA was 1:2,048. CONCLUSIONS: It is feasible to produce anti-L-PGDS antibody by immunizing hens with recombinant pGEX-2T/htL-PGES DNA.

Animals↗

PubMed2002

[Advances in sperm capacitation].

Sperm must be capacitated before sperm-ovum fusion. Capacitation was once considered as hyperactivation. But now many investigators thought that capacitation wasn't equal to hyperactivation, and that sperm hyperactivation might be a moiety of capacitation or the result of capacitation. In the present, the methods used to study sperm capacitation include fertilization in vitro, induction of sperm acrosome reaction, FITC-labeled chlortetracycline and plant hemoagglutinin. The studies on sperm capacitation in vitro mainly focused on the inductive substances of sperm capacitation and subsequent results analysis. It could lay foundation for the manifestation of molecular mechanism of sperm capacitation and destination of sperm capacitation in molecular levels.

Adenylyl Cyclases↗

PubMed2002

[Association between apolipoprotein E gene polymorphism and the patients with persistent vegetative state in the Chinese].

We studied the relationship between apolipoprotein E gene polymorphism and persistent vegetative state (PVS) to explore the genetics background of PVS, and evaluated the effect of ApoE gene polymorphism on lipid levels in plasma. The ApoE genotype of fifty-six patients with PVS and fifty-three controls were determined by PCR and restriction fragment length polymorphism (PCR-RFLP). Plasma lipid levels were measured by using routine methods. Results demonstrated that there were five genotypes in the two groups: E3/3, E3/4, E2/2, E2/3 and E2/4. The genotype frequencies of ApoE gene in PVS were 21(37.5%), 26(46.4%), 2 (3.6%), 5(8.9%), 2(3.6%) and that in control were 37(69.8%), 7(13.2%), 2(3.8%) 5(9.4%), 2(3.8%) respectively. We compared the genotype frequencies between the two groups and found there was a significantly increase in E3/4(chi 2 = 14.236, P < 0.001) and decrease in E3/3(chi 2 = 5.348, P < 0.05). epsilon 2, epsilon 3 and epsilon 4 allele frequencies of ApoE were 11(9.8%), 73(65.2%), 28(25%) in PVS and were 11 (10.4%), 86(81.1%), 9(8.5%) in control respectively. Allele frequencies, significantly increased in epsilon 4 (chi 2 = 10.533, P < 0.001) and decreased in epsilon 3 (chi 2 = 7.022, P < 0.01). We also found that E3/4, E2/4 genotype and epsilon 4 allele can largely increase total cholesterol (TC) and lower density lipoprotein cholesterol (LDL-C) levels in plasma, and epsilon 2 alleles also can largely increase LDL-C levels inplasma. Our finding indicates that the ApoE gene polymorphism may be in association with the PVS, and may be a factor in the genetic susceptibility to PVS in Chinese; Genotype and alleles of ApoE in PVS can affect the lipid levels in plasma.

Adolescent↗