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H Li

Publications and source records attributed to H Li.

At least 55 records · Page 3Linked to original sources
PubMed2006

Plasminogen activator inhibitor-1 promoter polymorphism is not associated with the aggressiveness of disease in prostate cancer.

AIMS: PAI-1 (plasminogen activator inhibitors-1) regulates plasminogen activation, and is related to tumour development. This study aims to test whether the promoter polymorphism in the PAI-1 gene is related to the aggressiveness of disease in prostate cancer. MATERIALS AND METHODS: In the present study, Taqman SNP genotyping assay was used to detect PAI-1 4G/5G polymorphism in DNA from paraffin-embedded tissues of 98 Caucasian patients with prostate cancer. RESULTS: The distribution of the genotypes is in Hardy-Weinberg equilibrium. The genotype had no statistically significant relationship with other prognostic factors. Similar risks for recurrence were seen in individuals with the 4G/4G and 4G/5G genotypes compared to those with 5G/5G genotype (odds ratio [OR] 2.65, 95% CI: 0.41-16.94, P = 0.30; OR = 2.19, 95% CI: 0.38-12.49, P = 0.38). CONCLUSION: We concluded that PAI-1 promoter polymorphism is not associated with the aggressiveness of disease in prostate cancer.

Aged↗
PubMed2006

Classification of a diverse set of Tetrahymena pyriformis toxicity chemical compounds from molecular descriptors by statistical learning methods.

Toxicity of various compounds has been measured in many studies by their toxic effects against Tetrahymena pyriformis. Efforts have also been made to use computational quantitative structure-activity relationship (QSAR) and statistical learning methods (SLMs) for predicting Tetrahymena pyriformis toxicity (TPT) at impressive accuracies. Because of the diversity of compounds and toxicity mechanisms, it is desirable to explore additional methods and to examine if these methods are applicable to more diverse sets of compounds. We tested several SLMs (logistic regression, C4.5 decision tree, k-nearest neighbor, probabilistic neural network, support vector machines) for their capability in predicting TPT by using 1129 compounds (841 TPT and 288 non-TPT agents) which are more diverse than those in other studies. A feature selection method was used for improving prediction performance and selecting molecular descriptors responsible for distinguishing TPT and non-TPT agents. The prediction accuracies are 86.9% approximately 94.2% for TPT and 71.2% approximately 87.5% for non-TPT agents based on 5-fold cross-validation studies, which are comparable to some of earlier studies despite the use of more diverse sets of compounds. The selected molecular descriptors are consistent with those used in other studies and experimental findings. These suggest that SLMs are useful for predicting TPT potential of diverse sets of compounds and for characterizing the molecular descriptors associated with TPT.

Animals↗
PubMed2006

N2-carboxyethyl-2'-deoxyguanosine, a DNA glycation marker, in kidneys and aortas of diabetic and uremic patients.

Advanced glycation end product (AGE)-mediated modification of proteins is enhanced both in the kidneys and aortas of diabetic and uremic patients. However, AGE modification of deoxyribonucleic acid (DNA) has not yet been reported in these patients. We performed immunohistochemistry of kidneys and aortas using a monoclonal antibody against N(2)-carboxyethyl-2'-deoxyguanosine (CEdG), a marker of AGE-linked DNA. A total of 20 kidneys and 20 aortas were obtained by autopsy. The kidney samples consisted of two groups: nondiabetic nonkidney disease (control) and diabetic nephropathy. The aorta samples consisted of four groups: nondiabetic nonkidney disease (control), diabetes, hemodialysis, and diabetic hemodialysis. In the kidneys CEdG was detected predominantly in the nuclei of epithelial cells, mesangial cells, and endothelial cells of the glomeruli, parietal epithelial cells, and tubular cells. The number of CEdG-positive cells in the glomeruli was significantly increased in diabetic nephropathy compared with control. In the aortic walls, CEdG was detected predominantly in the nuclei of macrophages and myofibroblasts. The number of CEdG-positive cells in the aorta was significantly increased in hemodialysis patients and diabetic hemodialysis patients compared with control. The highest number of CEdG-positive cells in the aorta was observed in diabetic hemodialysis patients. In conclusion, AGE-mediated modification of DNA is enhanced in the kidney of diabetic nephropathy and the aorta of uremic atherosclerosis, and may induce a loss of genetic integrity in these diseases.

Adult↗
PubMed2006

Intravenous delivery of anti-RhoA small interfering RNA loaded in nanoparticles of chitosan in mice: safety and efficacy in xenografted aggressive breast cancer.

Overexpression of RhoA in cancer indicates a poor prognosis, because of increased tumor cell proliferation and invasion and tumor angiogenesis. We showed previously that anti-RhoA small interfering RNA (siRNA) inhibited aggressive breast cancer more effectively than conventional blockers of Rho-mediated signaling pathways. This study reports the efficacy and lack of toxicity of intravenously administered encapsulated anti-RhoA siRNA in chitosan-coated polyisohexylcyanoacrylate (PIHCA) nanoparticles in xenografted aggressive breast cancers (MDA-MB-231). The siRNA was administered every 3 days at a dose of 150 or 1500 microg/kg body weight in nude mice. This treatment inhibited the growth of tumors by 90% in the 150-microg group and by even more in the 1500-microg group. Necrotic areas were observed in tumors from animals treated with anti-RhoA siRNA at 1500 microg/kg, resulting from angiogenesis inhibition. In addition, this therapy was found to be devoid of toxic effects, as evidenced by similarities between control and treated animals for the following parameters: body weight gain; biochemical markers of hepatic, renal, and pancreatic function; and macroscopic appearance of organs after 30 days of treatment. Because of its efficacy and the absence of toxicity, it is suggested that this strategy of anti-RhoA siRNA holds significant promise for the treatment of aggressive cancers.

Animals↗
PubMed2006

Tissue expression and association with fatness traits of liver fatty acid-binding protein gene in chicken.

Fatty acid-binding proteins belong to a superfamily of lipid-binding proteins that exhibit a high affinity for long-chain fatty acids and appear to function in metabolism and intracellular transportation of lipids. The current study was designed to investigate expression characterization and association with growth and composition traits of the liver fatty acid-binding protein (L-FABP) gene in the chicken. Northern blot analysis indicated that the gene, similar to the mammal L-FABP gene, was expressed only in liver and intestinal tissues. The mRNA levels of the chicken L-FABP gene in liver and intestine had significant differences between the broilers and Baier layers. The China Agricultural University F(2) population was used in the present study. Body weight and body composition traits were measured in the populations. Primers for the coding region and 5' upstream region of the L-FABP gene were designed according to chicken genomic and cDNA sequence. Polymorphisms were detected by DNA sequencing, and the PCR single-strand conformation polymorphisms method was developed to genotype the F(2) population. The results indicated that the L-FABP gene polymorphisms were associated with abdominal fat weight and percentage of abdominal fat, and the L-FABP gene could be a candidate locus or linked to a major gene(s) that affects fatness traits in the chicken. The results of the current study provided basic molecular information for studying the role of the L-FABP gene in the regulation of lipid metabolism in avian species.

Abdominal Fat↗
PubMed2006

Single marker and haplotype analysis of the chicken apolipoprotein B gene T123G and D9500D9- polymorphism reveals association with body growth and obesity.

Apolipoprotein B (apoB) is synthesized in the mammalian small intestine and liver, where it serves an essential role in the assembly and secretion of triglyceride-rich lipoproteins and is the constituent of very low density lipoprotein, intermediate density lipoprotein, and low density lipoprotein (LDL), and is the ligand for the LDL receptor. The present study was designed to investigate the effects of the apoB gene on chicken growth and deposition of adipose tissues. The Northeast Agricultural University broiler lines divergently selected for abdominal fat were used. Two novel polymorphisms, a synonymous mutation T-->G at 123 of 26th exon, and a 9 bp deletion at 500 bp after the stop code TGA of the apoB gene were found, and then the association between these 2 polymorphisms and traits were detected using both single marker and haplotype analysis. Results showed that the haplotype of the 2 polymorphisms of apoB gene was linked with potential major loci or genes affecting the body growth and fatness traits. The results of the present study not only suggest a primary function of apoB gene in the chicken, but also suggest that the use of molecular genetic markers associated with the apoB gene can be used in a selection program for low abdominal fat.

Abdomen↗
PubMed2006

Identification of single nucleotide polymorphism of adipocyte fatty acid-binding protein gene and its association with fatness traits in the chicken.

Fatty acid-binding proteins (FABP) belong to a superfamily of lipid binding proteins that exhibit a high affinity for long chain fatty acids and appear to function in metabolism and intracellular transportation of lipids. The current study was designed to investigate the effects of the adipocyte (A)-FABP gene on chicken growth and body composition traits. Two F2 resource populations were used in the current study. Body weight and body composition traits were measured in the populations. Primers for the coding region of the A-FABP gene were designed from chicken genomic and cDNA sequences. Polymorphism between parental lines was detected by DNA sequencing, and the PCR-RFLP method was developed to genotype the F2 populations. The results indicated that an A-FABP gene polymorphism was associated with abdominal fat weight and percentage of abdominal fat, and the A-FABP gene could be a candidate locus or linked to a major gene(s) that affects abdominal fat content in the chicken.

Animals↗
PubMed2006

Differentiation potential of human embryonic mesenchymal stem cells for skin-related tissue.

BACKGROUND: Mesenchymal stem cells (MSC) have the capacity to differentiate into cells of connective tissue lineages, including bone, fat, cartilage and muscle, but the differentiation of embryonic MSC into epidermal cells by mesenchymal-epithelial transition has not been confirmed. OBJECTIVES: To determine the biological characteristics of human embryonic MSC (hMSC) and their potential for differentiation into epithelial cells. METHODS: hMSC were derived from 4-7-week-old embryos; they were localized and isolated, then primary culture was done. The biological characteristics of hMSC were detected by immunohistochemical methods and flow cytometry. Their differentiation potential was determined by coculture with conditioning medium and in vivo injection. RESULTS: hMSC express the relative specific antigens of MSC, such as SH2, alpha-smooth actin, CD29, CD44, CD90 and S100. After stimulation and in vivo transplantation, hMSC possess the potential to differentiate into epidermal cells with the production of keratin 19 and E-cadherin. CONCLUSIONS: hMSC derived from the early human embryo have the ability to transform into epidermal cells in vivo and in vitro.

Animals↗
PubMed2006

Association of TNF-alpha promoter polymorphisms with the outcomes of hepatitis B virus infection in Chinese Han population.

Host genetic factors and environment factors including hepatitis B virus (HBV) genotypes are widely studied for the different outcomes of HBV infection. Recent studies suggest that tumour necrosis factor-alpha (TNF-alpha) plays a pivotal role in the viral clearance and host immune response to HBV, and the capacity for TNF-alpha production in individuals is influenced by a major genetic component. In this study, we aimed to explore whether the single-nucleotide polymorphisms (SNPs) of TNF-alpha promoter are associated with the outcomes of HBV infection in the Chinese Han population. One hundred and forty-three spontaneously recovered HBV subjects and 196 chronic hepatitis B patients were recruited in this case-control study in the Beijing area of China. Polymerase chain reaction-restriction fragment-length polymorphism (PCR-RFLP) and sequence-specific primer-PCR (SSP-PCR) were used to detect the SNPs of five sites in the TNF-alpha promoter (-238G/A, -308G/A, -857C/T, -863C/A, -1031T/C). The frequency distributions of genotypes and haplotypes in two groups were analysed by EPI and EH programs. The presence of the -238GG genotype was significantly correlated with persistence of HBV infection (OR = 4.08, P = 0.02), and -857TT genotype appeared in relation to the spontaneous clearance of HBV (OR = 0.47, P = 0.03). Frequency of haplotype GGCCT (-238/-308/-857/-863/-1031) in the chronic HB group was significantly lower than that in spontaneously recovered group (P = 0.03), and frequencies of haplotypes GGCAT and GGTAT in the chronic HB group were significantly higher than those in the spontaneously recovered group (P = 0.0001, P = 0.0004). In conclusion, TNF-alpha promoter polymorphisms are independently associated with different outcomes of HBV infection.

Adult↗
PubMed2006

Antepartum immunoprophylaxis of three doses of hepatitis B immunoglobulin is not effective: a single-centre randomized study.

To investigate the efficacy of antepartum administration of three doses of hepatitis B immunoglobulin (HBIg), currently being used in China, 250 pregnant women who were seropositive for hepatitis B e antigen (HBeAg) were randomly divided into study (117 cases) and control groups (133 cases). Subjects in the study group received HBIg 400 IU intramuscularly once a month at the third, second and first month before delivery; subjects in the control group received no antepartum treatment. All neonates received passive-active immunization after birth. The maternal hepatitis B virus (HBV) markers, hepatitis B surface antigen (HBsAg) titres and HBV deoxyribonucleic acid (DNA) levels were measured at week 28 of gestation (before the antepartum treatment) and at labour; the neonatal serum HBV markers were detected at birth and at 12 months after birth. No side-effects were found in any of the women or their neonates. No statistical differences were seen between the maternal HBsAg and HBV DNA levels of the study and control groups at labour nor the protective efficacy rates of postnatal immunoprophylaxis at 12 months after birth (P > 0.05, respectively). To conclude, antepartum administration of three doses of HBIg for the HBeAg-positive women is inefficacious.

Adult↗
PubMed2006

Functional hierarchical models for identifying genes with different time-course expression profiles.

Time-course studies of gene expression are essential in biomedical research to understand biological phenomena that evolve in a temporal fashion. We introduce a functional hierarchical model for detecting temporally differentially expressed (TDE) genes between two experimental conditions for cross-sectional designs, where the gene expression profiles are treated as functional data and modeled by basis function expansions. A Monte Carlo EM algorithm was developed for estimating both the gene-specific parameters and the hyperparameters in the second level of modeling. We use a direct posterior probability approach to bound the rate of false discovery at a pre-specified level and evaluate the methods by simulations and application to microarray time-course gene expression data on Caenorhabditis elegans developmental processes. Simulation results suggested that the procedure performs better than the two-way ANOVA in identifying TDE genes, resulting in both higher sensitivity and specificity. Genes identified from the C. elegans developmental data set show clear patterns of changes between the two experimental conditions.

Algorithms↗
PubMed2006

Sequencing-based analysis of the HLA-DPB1 polymorphism in Nu ethnic group of south-west China.

In the present study, DNA typing for HLA-DPB1 was performed using polymerase chain reaction-sequencing-based typing method in 72 randomly selected Nu ethnic individuals inhabiting the Yunnan province of south-west China. Among the 12 detected DPB1 alleles, the most frequent was DPB1*1301, with the percentage of 20.83%, followed by DPB1*0501 (19.44%), DPB1*040101 (16.67%) and DPB1*2801 (9.72%). The allele DPB1*1501 was found for the first time in the Chinese population. Neighbour-joining showed that the Nu ethnic minority belonged to East Asian cluster and was most closely related to Lisu, being consistent with the historical records. In addition, the results obtained in this study will also provide useful information on organ transplantation, forensic investigations and disease association studies.

China↗
PubMed2006

Association of TPH1 with suicidal behaviour and psychiatric disorders in the Chinese population.

Tryptophan hydroxylase (TPH), the rate limiting enzyme in serotonin biosynthesis, is one of the most important regulating factors in the serotonergic system. Recently, polymorphisms of the TPH gene have been identified as being associated with suicide, but the evidence is inconsistent. To investigate the role in suicide of one of the isoforms, TPH1, we examined the association of five single nucleotide polymorphisms (SNPs) in the promoter region and in intron 7 of the TPH1 gene based on a sample from the Chinese population of 810 subjects, of whom 329 had made no suicide attempts (NSA), 297 had made suicide attempts (SA), and 184 were healthy subjects (HS). In this study, we observed statistically significant differences between NSA and HS subjects in allele distributions on one marker, -6526A (p = 0.0329; odds ratio (OR) 1.36; 95% confidence interval (CI) 1.01 to 1.81). No significant difference in genotype distribution or allele frequencies of other polymorphisms was found between the suicide victims and the controls. The overall haplotype frequency was significantly different between cases and healthy controls (p = 0.000024 NSA v HS; p < 0.000001, SA v HS; p < 0.000001, cases v HS). We found the haplotype TCAAA of -7180/-7065/-6526/218/779 to be strongly associated with suicidal behaviour and psychiatric disorders (p = 0.00243; OR = 1.62; 95% CI 1.17 to 2.24 and p = 0.018; OR = 1.41; 95% CI 1.05 to 1.91), which suggests an association of TPH1 with suicidal behaviour and indicates that TPH1 may play a significant role in the aetiology of psychiatric disorders in the Han Chinese population.

Alleles↗
PubMed2006

Inhibitive effect of genistein on interleukin-8 expression in cultured human retinal pigment epithelial cells.

Recent studies showed that interleukin-8 (IL-8) played an important role in retinal neovascularization. In this study, the effects of genistein on the expression of IL-8 in the arising retinal pigment epithelia-19 cells were studied. The levels of IL-8 protein expression in supernatants were punctually detected by ELISA. When the cells were treated with hypoxia (5% CO2, 95% N2), IL-8 secretion increased from 0.29 +/- 0.04 to 2.59 +/- 0.42 ng/ml. To study calcium-dependent IL-8 expression, cells were treated with KCl at 25 mM, norepinephrine (NE) at 10 nM, and glutamate (Glu) at 1 microM for 8 h. As a result, the levels of IL-8 protein in supernatants were significantly increased compared with that in the controls. When the cells are treated with genistein (50, 100, 200 microM) for 30 min before hypoxia or stimulations by KCl, NE, and Glu, the elevated expression of IL-8 protein was all suppressed in a concentration-dependent manner. These results suggested that suppression of IL-8 expression in retinal pigment epithelial cells might partly account for the inhibitive effect of genistein on retinal neovascularization.

Cell Hypoxia↗
PubMed2006

Recombinant adenoviruses expressing TRAIL demonstrate antitumor effects on non-small cell lung cancer (NSCLC).

INTRODUCTION: Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) induces apoptosis in a variety of malignant cells, but not in normal cells. This preferential toxicity to the abnormal cells renders TRAIL potentially a very powerful therapeutic weapon against cancer. However, a requirement for large quantities of TRAIL to suppress tumor growth in vivo is one of the major factors that has hindered it from being widely applied clinically. To overcome this, we constructed a replication-deficient adenovirus that carries a human full-length TRAIL gene (Ad-TRAIL) and tested its efficacy against a lung cancer model system in comparison to that of the recombinant soluble TRAIL protein. METHODS: To investigate the antitumor activity and therapeutic value of the Ad-TRAIL on the non-small cell lung cancer (NSCLC), four NSCLC cell lines, namely, YTMLC, GLC, A549, and H460 cells, were used. TRAIL protein expression was determined by Western blotting and flow cytometry. Cell viability was analyzed by proliferation assay, and DNA ladder and cell-cycle analysis were used to identify apoptosis. To further evaluate the effect of Ad-TRAIL in vivo, YTMLC cells were inoculated to the subcutis of nude mice. The Ad-TRAIL was subsequently administered into the established tumors. Tumor growth and the TRAIL toxicity were evaluated after treatment. RESULTS: YTMLC cells infected with Ad-TRAIL showed decreased cell viability and a higher percentage of apoptosis. Similar, Ad-TRAIL treatment also significantly suppressed tumor growth in vivo. CONCLUSIONS: TRAIL gene therapy provides a promising therapy for the treatment of NSCLC.

Adenoviridae↗
PubMed2006

The application of stem cells in the treatment of ischemic diseases.

Ischemia causes oxygen deprivation, cell injury and related organ dysfunction. Although ischemic injury may be local, it involves many biochemical changes in different cell types. The ability of stem cells to differentiate into different cell lineages provides the possibility of their use in treating a variety of diseases requiring tissue repair or reconstitution, such as stroke, ischemic retinopathy, myocardial infarction, ischemic disorders of the liver, ischemic renal failure, and ischemic limb dysfunction. Several cell types including embryonic stem cells, various progenitor and stem cells of hematopoietic or mesenchymal origin have been used in attempts to reconstitute injured tissue. Xenologous or autologous stem cells may be administered either through the peripheral vascular system or directly by regional injection. The stem cells are then guided to the infarct site by homing signals. Either by cell differentiation or paracrine effects, stem cells or progenitor cells participate in the reconstruction of a favorable microenvironment resulting in neovascularization and tissue regeneration that eventually improve the physiological function of organs with ischemic damage.

Animals↗
PubMed2006

Central and/or peripheral immunoreactivity of orexin-A in pregnant rats and women.

Orexins (A and B) have been implicated in feeding behavior, energy balance and state of vigilance. During pregnancy, their involvement in feeding regulation and reproduction are poorly understood. In this study, we investigated orexin-A immunoreactivity in the hypothalamus and serum in pregnant rats and women by immunofluorescence staining, image analysis and radioimmunoassay, examined the correlation of serum orexin-A and leptin with gestational age in pregnant women by regression analysis, and explored the effect of leptin injected intracerebroventricularly (i.c.v.) on orexin-A immunoreactivity in the hypothalamus of normal rats by immunohistochemistry. The results showed that pregnant rats had significantly greater daily food intake on days 15 and 20 of pregnancy than virgin ones (+27.3%, P< 0.01 and +38.6%, P< 0.001 respectively), with significantly fewer number and lower mean staining intensity of orexin-A-immunoreactive (ir) neurons on days 16 (both P< 0.05) and 21 (both P< 0.01) of pregnancy. Moreover, serum levels of orexin-A exhibited 2.0-fold and 2.2-fold increases (both P< 0.001) in rats on days 16 and 21 of pregnancy compared with those in virgin rats, and 1.9-fold and 2.0-fold increases (both P< 0.001) in mid (13-26 weeks) and late pregnant women (27-40 weeks) compared with those in non-pregnant women. Simultaneously, serum levels of leptin showed a 2.3-fold and 2.2-fold increase (both P< 0.001) in rats on days 16 and 21 of pregnancy, and a 3.3-fold and 4.3-fold increase (both P< 0.001) in mid and late pregnant women. Serum levels of both orexin-A and leptin correlated positively with gestational age in pregnant women. Leptin injected i.c.v. significantly decreased the number (P< 0.01) and mean staining intensity (P< 0.01) of orexin-A-ir neurons in the hypothalamus, food intake (P< 0.01) and body weight gain (P< 0.001) compared with vehicle injection in normal rats. These results suggested that central and serum orexin-A might be involved in the regulation of feeding and energy metabolism during pregnancy. The change in central orexin-A immunoreactivity might be related to the increased serum leptin concentrations.

Animals↗