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Biomedical subjects

Lei Wang

Publications and source records attributed to Lei Wang.

At least 163 records · Page 9Linked to original sources
PubMed2006

Systematic screening for polymorphisms in the CYP3A4 gene in the Chinese population.

OBJECTIVES: Cytochrome P450 3A4 (CYP3A4) is a major CYP enzyme in the liver and intestine. It is involved in the metabolism of over 50% of all drugs currently in use. The present study was designed to determine the genetic basis of CYP3A4 variability. METHODS: Single nucleotide polymorphism (SNP) analysis of the CYP3A4 gene was performed on 60 healthy Chinese subjects consisting of 20 Han, 30 She and ten Dong subjects, using direct sequencing. Linkage disequilibrium, haplotype inference and Hardy-Weinberg equilibrium were also determined for these samples. RESULTS: A total of 20 SNPs were found in the CYP3A4 gene, including 11 known SNPs and nine novel SNPs. The known SNPs detected in our study were CYP3A4*1B, CYP3A4*1G, CYP3A4*10, CYP3A4*13, CYP3A4*14, CYP3A4*15, CYP3A4*17, CYP3A4*18, rs3091339, rs3091430 and rs28371761, and the novel SNPs were -658 A-->C, G27A (E10K), T48A, G14284A (G167D), A15623G (N191D), C15635A (L196I), T15656C (F203L), G14199A (intron 5) and C15566T (intron 6). The allelic frequencies found in our sample varied from 1-37%. The novel SNPs detected in the CYP3A4 gene suggest that the Chinese population has different patterns of allele frequency compared with other populations. CONCLUSION: Several SNPs were detected in the CYP3A4 gene. The study of genetic variants in CYP3A4 may have an important significance for the understanding of genotype and phenotype relationships.

Adult↗
PubMed2006

Streptococcus suis sequence type 7 outbreak, Sichuan, China.

An outbreak of Streptococcus suis serotype 2 emerged in the summer of 2005 in Sichuan Province, and sporadic infections occurred in 4 additional provinces of China. In total, 99 S. suis strains were isolated and analyzed in this study: 88 isolates from human patients and 11 from diseased pigs. We defined 98 of 99 isolates as pulse type I by using pulsed-field gel electrophoresis analysis of SmaI-digested chromosomal DNA. Furthermore, multilocus sequence typing classified 97 of 98 members of the pulse type I in the same sequence type (ST), ST-7. Isolates of ST-7 were more toxic to peripheral blood mononuclear cells than ST-1 strains. S. suis ST-7, the causative agent, was a single-locus variant of ST-1 with increased virulence. These findings strongly suggest that ST-7 is an emerging, highly virulent S. suis clone that caused the largest S. suis outbreak ever described.

Animals↗
PubMed2006

[Establishment of a rat model of alcoholic liver fibrosis induced by complex factors].

OBJECTIVE: To establish a model of alcoholic liver fibrosis (ALF) in rats induced by complex factors. METHODS: Forty-seven healthy male rats were divided into three groups: normal control group (n=12), minor CCl4 group (n=12) and complex factors group (n=27). The rats in the complex factors group were fed a complex diet including alcohol, corn oil and pyrazole, and administered with intraperitoneal injection of minor CCl4 to induce ALF. During induction process, the histopathological changes of liver tissue and the values of liver-to-body weight ratio were both observed regularly. The serum levels of alanine aminotransferase (ALT), aspartate aminotransferase (AST) and gamma-glutamyltransferase (gamma-GT) in these three groups were all examined at the 12th week of the induction process. RESULTS: At the 12th week of the induction process, the model of ALF induced by complex factors was successfully established in rats, and the histopathological presentations showed alcoholic fatty liver, hepatitis and liver fibrosis in a sequence along with the induction process. The value of liver-to-body weight ratio and the serum levels of ALT, AST and gamma-GT of rats in the complex factors group were all significantly different from those in the other two groups. CONCLUSION: It is a steady and effective way to induce ALF in rats with complex diet and minor CCI4 injection.

Animals↗
PubMed2006

Evaluation of renal artery stenosis with velocity parameters of Doppler sonography.

OBJECTIVE: The purpose of this study was to evaluate the accuracy of velocity parameters for the diagnosis of renal artery stenosis (RAS) with color Doppler sonography and to determine the optimal threshold values for these parameters. METHODS: The study group was composed of 187 renal arteries, which were examined by color Doppler sonography and angiography. Four Doppler parameters, including the peak systolic velocities (PSVs) in the renal and interlobar arteries, the renal-aortic ratio, and the renal-interlobar ratio (RIR), were measured. Receiver operating characteristic curve analysis was performed to determine the optimal parameter. The sensitivity, specificity, and negative and positive predictive values at various threshold values were calculated. RESULTS: Doppler sonographic examination was technically successful in 96% of renal arteries (180/187). The RIR was determined to be the best parameter. With threshold values of RIR greater than 5, PSV greater than 150 cm/s in the renal artery, renal-aortic ratio greater than 2, and PSV less than 25 cm/s in the interlobar artery, the sensitivity values were 88%, 81%, 70%, and 74%, respectively. An RIR greater than 5 and PSV less than 15 cm/s in the interlobar artery provided the optimal combination of parameters, with sensitivity and specificity of 91% and 87%, respectively. CONCLUSIONS: The RIR is the best velocity parameter in the detection of RAS (> or =50%), and its best cutoff is 5. Valuing influencing factors of PSV in the renal artery will help reduce misdiagnosis. The combination of RIR greater than 5 and PSV less than 15 cm/s in the interlobar artery provides the best diagnostic efficiency of RAS.

Adolescent↗
PubMed2006

[Experimental research on immunological rejection in neural stem cells allograft].

AIM: To investigate the occurrence of immunological rejection in brain transplantation of neural stem cells (NSCs) in the rat of Parkinson's disease model. METHODS: NSCs derived from the brain of E14.5d SD rat were cultured in vitro. Single cell suspensions were grafted into the striatum of the rat model of Parkinson's disease. Surviving animals were sacrificed at 10, 21, 35 and 60 d after transplantation, and the brain tissue was stained with HE and immunocytochemically to detect the expression of tyrosine hydroxylase (TH), CD4, CD8 and major histocompatibility complex class II antigens (MHC-II). RESULTS: The expression of elicited CD4, CD8 and MHC-II was detected within and around the allografts in the graft groups at 10 and 21 d after grafting and was subsiding at 35 d. At 60 d only very occasional immunopositive cells were present. The number of TH positive neurons was low at 10, 21 d, but increased at 35 d and 60 d. There was no significant difference between negative and positive control groups at different time points. The rotation behavior of PD was decreased 35 d after transplantation. CONCLUSION: Intracerebral transplantation of NSCs did not cause remarkable immunological rejection.

Animals↗
PubMed2006

[The effect of limb salvage on treating osteosarcoma with pathological fracture in two cases].

OBJECTIVE: To investigate the effect of limb salvage on treating osteosarcoma with pathological fracture. METHODS: From October 2002 to January 2003, 2 cases of osteosarcoma with pathological fracture were treated by limb salvage. Intra-arterial chemotherapy was given by subcutaneous implantable delivery system with caffeine. Replacement with prosthesis was performed after 5 times of chemotherapy. RESULTS: Two patients were followed up for twenty-four months and 21 months respectively. No infection, aseptic loosening, local recurrence or metastasis occurred, and function recovery of joints was satisfactory. CONCLUSION: Limb salvage can be considered in condition that primary osteosarcoma with pathological fracture can be treated by effective and comprehensive chemotherapy.

Adolescent↗
PubMed2006

[The effect of serum rich in platelet-released growth factors on proliferation of rat osteoblast in vitro].

OBJECTIVE: To study the effect of serum rich in platlelet-released growth factors on the biological functions of rat osteoblast. METHODS: Rat osteoblasts were isolated from parietal bone of fetal Spraque-Dawley (SD) rat. Platelet-rich plasma(PRP) and platelet-poor plasma (PPP) obtained from healthy SD rat were activated by thrombin to get serum rich in growth factors (SRGF) or serum poor in growth factors (SPGF). The cells were treated with 1.25%, 2.5%, 5% SRGF or SPGF, and cellular mitogenic activity was evaluated by thiazoly blue (MTT) colorimetric assay. Results When compared with SPGF at the same concentration, SRGF promoted the proliferation of rat osteoblast significantly (P = 0.002 - 0.004), and the proliferation seemed to correlate with the concentration of SRGF (Spearman's correlation coefficient, r(s) = 0.834). CONCLUSION: SRGF is capable of upregulating the proliferation of rat osteoblast.

Animals↗
PubMed2006

[Development of antisense nucleotides for therapy].

Antisense oligonucleotides (ASODN) for therapy is a genetic technology which is based on the base-complementary principle. DNA or RNA sequence synthesized by biotechnology is transferred into the target cells to form mRNA-DNA or mRNA-RNA double strand for inhibiting the expression of target genes. In this way we can control and treat some diseases. The development of antisense oligonucleotides drugs has opened a new area of genetic pharmacology. This paper reviews its classifications, mechanics and its wide application in the treatment of viral infection, tumor and cardiovascular diseases. At the same time we pose the problems that need solving.

Arterial Occlusive Diseases↗
PubMed2006

[Changes of sphincter preserving rate in lower rectal cancer and analysis of their related factors].

OBJECTIVE: To analyze the factors related to sphincter preserving(SP) operation for lower rectal cancer. METHODS: Clinicopathological data of 316 patients with lower rectal cancer 1-5 cm from the anorectal line who underwent surgical resection from Aug. 1994 to Nov. 2005 were analyzed. The whole period was divided into two period based on the introduction of TME in Jan. 1999. The SP rates, leakage between the two period were compared. RESULTS: The SP rate increased significantly from 44.9 % in period I (Aug. 1994-Dec. 1998) to 76.2 % in period II (Jan. 1999-Nov. 2005)(P=0.000). The factors significantly influencing SP were the distance from the anorectal line, sex, period, circumference of intramural spread, histological differentiation (P< 0.05). Significant differences were detected between the two period in sex, volume of blood transfusion, Dukes' stage (P< 0.05). The rate of leakage were 2.7 % and 1.3 % in the two period (P > 0.05). CONCLUSIONS: Over 12 years, the SP rate of rectal cancers 1-5 cm from the anorectal line was significantly increased and volume of blood transfusion reduced obviously due to the introduction of TME. These surgical techniques, however, have no effect on the operating time and leakage rates.

Anal Canal↗
PubMed2006

[Effect of dexamethasone on expression of fractalkine in lipopolysaccharide-induced acute lung injury].

OBJECTIVE: To investigate the effect of dexamethasone on the expression of fractalkine (FKN) in lipopolysaccharide (LPS)-induced acute lung injury (ALI). METHODS: The rat model of ALI was established by injection of LPS at the dose of 4 mg/kg. 42 Wistar rats were randomly divided into the normal group (n=6), LPS group (n=18), and dexamethasone (DEX) group (n = 18), and then the rats in both LPS and DEX groups were divided into three subgroups (1 h, 2 h and 4 h after injection of LPS), respectively. The pathological condition and the wet/dry ratio (W/D) of the lung were observed, and serum TNF-alpha level, and FKN mRNA of the lung were detected with ELISA and RT-PCR. RESULTS: The W/D, serum TNF-alpha level, and FKN mRNA of the lung were significantly increased in LPS group, compared with those in normal group (all P < 0.05), but the W/D, serum TNF-alpha level, and FKN mRNA of the lung in the DEX group were much more decreased than those in the LPS group (all P < 0.05). In addition, the expression of FKN mRNA in the lung tissue positively correlated with the concentration of TNF-alpha (r = 0.674, P <0.05). CONCLUSION: The findings suggested that pre-treatment with dexamethasone could inhibit the TNF-alpha level and prevent the increase of the expression of FKN mRNA, which may be one of the mechanisms by which DEX serves as a protection against LPS-induced lung injury.

Animals↗
PubMed2006

[Dynamic change of metabolism related protein in liver tissue of rats' model of hepatic fibrosis and regulatory effect of fuzheng huayu decoction on it].

OBJECTIVE: To investigate the effect of Fuzheng Huayu decoction (FHD) intervention on hepatic fibrosis. METHODS: Wistar rats were randomly divided into 3 groups: rats in the normal group only treated with subcutaneous injection of saline, rats in the model group and the FHD group were made into hepatic fibrosis by subcutaneous injection of 40% carbon tetrachloride (CCl4)-olive solution and then those in the FHD group were treated with FHD by gastric perfusion after modeling. Liver samples of the rats were obtained for routine pathological observation, hydroxyproline determination and proteome quantitative determination. After then, the proteome profile was obtained through 2-dimensional electrophoresis and silver staining, and analyzed. More than 30 proteins with different expression were identified by MALDI-TOF-MS. RESULTS: (1) The integral response of vital movement such as body weight and activity of hepatic fibrosis declined in the CCl4 induced liver fibrosis rats; (2) Liver fibrosis were associated with abnormal metabolism; (3) There were four material metabolism-related protein showed by hepatic proteome mass spectrography, which expressed different between the normal and the fibrotic rats, i. e. the perchloric acid soluble protein, the phosphatidylinositol transferase, the phosphoglycerate kinase and the endoplasmic reticulum-60 protease; (4) The expressions of the above-mentioned four proteins in the FHD group were nearly the same as those of normal level. CONCLUSION: (1) Liver fibrosis is accompanied with abnormal protein synthesis and decomposition, as well as the enhanced activity of glycolysis; (2) The existence of metabolism-related proteins is one of the elements for the liver in regulating metabolism; (3) The regulation on the expressions of metablism-related proteins is one of the pathways for FHD to exert its anti-hepatic fibrosis effect.

Animals↗
PubMed2006

[Problems and strategies in clinical trials of traditional Chinese medicine].

To explore the problems and the strategies in clinical trials of traditional Chinese medicine (TCM), including the method and concealment of randomizing, equipoise of baseline, blindness and outcome measures, adverse reaction observation, statistical method and publication bias. The consolidated standard of reporting trials (CONSORT) is recommended to be applied in order to improve the quality of design and report of randomized controlled trials (RCTs) of TCM, and in case of human is taken as the subject of trial, according to the fundamental ethical principle, the clinical trial design should be censored by institutional review board (IRB), and the informed consent should be signed to protect the rights and interests of the trial participator.

Humans↗
PubMed2006

[The relationship between high sensitivity C-reactive protein level at admission and myocardial perfusion after primary percutaneous intervention in patients with acute myocardial infarction].

OBJECTIVE: This study was designed to investigate the relationship between high sensitivity C-reactive protein (hs-CRP) level at admission and myocardial perfusion after percutaneous coronary intervention (PCI) in patients with acute myocardial infarction. METHODS: The study population consisted of 197 patients (154 men, mean age 60.94 +/- 11.62 years) who were admitted to our hospital with first acute myocardial infarction and underwent primary PCI in the infarct-related artery. Myocardial perfusion was evaluated by Thrombolysis In Myocardial Infarction (TIMI) myocardial perfusion grade (TMPG). Patients were divided into two groups according to TMPG after PCI. Group 1 consisted of 39 patients with TMPG 0 - 1 and group 2 consisted of 158 patients with TMPG 2 - 3. Serum hs-CRP levels at admission were measured. RESULTS: hs-CRP level at admission was significantly higher in group 1 than that in group 2 (P = 0.026). CONCLUSIONS: Higher hs-CRP level at admission in patients with acute myocardial infarction is related to poorer myocardial perfusion post primary PCI.

Aged↗
PubMed2006

[Valsartan eluting-stents inhibited neointimal hyperplasia by decreasing collagen deposition in rabbits].

OBJECTIVE: To assess the effect of valsartan eluting-stents on restenosis and collagen deposition in neointima hyperplasia in rabbits. METHODS: Valsartan eluting-stents and the carrier eluting-stents were made with patented multi-layers coating techniques. Bare stents (n = 8), carrier eluting-stents (n = 8) and valsartan eluting-stents (n = 10) were implanted into rabbit abdominal aortas, respectively. Quantitive angiography (QA) was performed before, immediately post and 3 months after stents implantations to determine the diameter of aortas. Rabbits were killed 3 months post stents implantation and the cross sections of the stented vessels were analyzed for neointimal formation: luminal area (LA), neointimal area (NIA), inner elastic lumina area (IELA), the maximal inner-membrane thickness (MIT) and percent stenosis. MASSON and picrosirius red staining were performed to observe the collagen deposition in neointima analyzed. RESULTS: The mean aortic diameters measured by QA at different time points were similar between the groups. LA was significantly larger (5 016 269 microm(2) +/- 207,934 microm(2) vs. 4,345,548 microm(2) +/- 125,822 microm(2) and 4,302,061 microm(2) +/- 167,952 microm(2), P < 0.01 vs. valsartan stents) while NIA (441,577 microm(2) +/- 74,099 microm(2) vs. 1,119,635 microm(2) +/- 163,503 microm(2) and 1,135,636 microm(2) +/- 136,555 microm(2)) and MIT (116 microm +/- 12 microm vs. 240 microm +/- 30 microm and 192 microm +/- 21 microm) as well as percent stenosis (8% +/- 2% vs. 20% +/- 2% and 21% +/- 2%) were significantly reduced in valsartan eluting-stents group compared to bare and carrier stents groups. MASSON and picrosirius red staining revealed rich type III collagen deposition in neointima and spare type I collagen patched around stents struts in bare and carrier stents groups and collagen deposition was rarely seen in neointima and stents struts in valsartan eluting-stents group. CONCLUSION: Valsartan eluting-stents inhibited neointimal hyperplasia by decreasing collagen deposition.

Animals↗
PubMed2006

[Clonality study of palmar fibromatosis].

OBJECTIVE: To study the clonality of palmar fibromatosis by molecular genetic analysis of X chromosome inactivation pattern at a polymorphic site of human androgen receptor gene (HUMARA). METHODS: Twelve female cases of palmar fibromatosis were enrolled into this study. Hematoxylin and eosin-stained sections of paraffin-embedded, formalin-fixed tissues were microdissected by laser capture microdissection technology in order to obtain the proliferative spindle cells. Tumor cells isolated from rectal adenocarcinoma in a female patient were used as positive control. The genomic DNAs were extracted with phenol and chloroform, digested with methylation-sensitive restriction endonuclease HpaII, and amplified by polymerase chain reaction (PCR) using primers targeted to a highly polymorphic short tandem repeat of HUMARA. The amplimers were separated on vertical 8% non-denaturing polyacrylamide gels and the patterns were visualized with ethidium bromide stain. RESULTS: The methodology for clonality analysis was validated in the positive control using rectal adenocarcinoma cells. Among the 12 cases studied, PCR amplification failed in 3 samples and 1 sample showed homozygosity which was not suitable for further analysis. Eight samples were successfully amplified and showed a random X chromosome inactivation pattern, suggesting polyclonality in these lesions. CONCLUSIONS: Palmar fibromatosis is a polyclonal condition and should be considered as a form of non-neoplasmic fibroblastic proliferation.

Actins↗
PubMed2006

[The effect of Fuzheng Huayu Decoction on the hepatic proteome during the formation and resolution of rat liver fibrosis].

OBJECTIVE: To investigate the dynamic changes of the hepatic proteome during the formation and resolution of rat liver fibrosis induced by carbon tetrachloride and the effect of Fuzheng Huayu Decoction on it. METHODS: Liver fibrosis in Wistar rats was induced by subcutaneous injection of 40% CCl4 in olive oil while the rats in the treatment group received Fuzheng Huayu Decoction. Pathological examination, hydroxyproline content determination and protein extraction of the rats livers were performed at four time points, i.e. at the end of 4, 8, 12 and 16 weeks. After 2-dimensional electrophoresis (2-DE), the gels were analyzed using the PDQUEST 2-DE image analysis software and differentially expressed proteins were identified using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS). RESULTS: (1) The 2-DE examination showed that the model group-specific proteins and differentially expressed proteins presented started at 4 weeks and reached their peaks at 12 weeks, and this was conformed by MALD-TOF-MS identification. (2) In addition, 18 proteins were present at all time points and another 19 proteins were absent in the model group among those identified by MALD-TOF-MS. (3) Fuzheng Huayu Decoction down-regulated proteins and their expressions increased at 4 and 8 weeks, whereas it up-regulated those which decreased at 8, 12 and 16 weeks. CONCLUSIONS: (1) The changes in protein expressions, which effect metabolism, neuroendocrine function and cell proliferation, are the basis of liver fibrosis. (2) The anti-fibrotic effect of Fuzheng Huayu Decoction is holistic, specifically because it can decrease the abnormal cell proliferation and can increase the synthesis of normal proteins.

Animals↗
PubMed2006

[Atmospheric particle-retaining capability of eleven garden plant species in Beijing].

With eleven garden plant species in Beijing as test materials, this paper determined the adhesion density of atmospheric particles on leaf surface, observed the micro-configurations of leaf epidermis, and measured the particle size distribution of the particles. The results showed that the particles were mainly adhered on upside leaf surface, and the adsorbed amount was about six times higher than that on underside leaf surface. The particle-retaining capability of the micro-configurations of leaf epidermis was decreased in the order of groove> vein + cell > cell > strip protuberance. The capability of particle-retaining was higher when the micro-configurations were denser and the fall between them was larger. The mean value and the mean percentages of PM2.5 and PM10 on upside leaf surface were 66.7% and 98.3%, while those on underside leaf surfaces were 43.4% and 92.9%, respectively.

Air Pollutants↗