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Wei Chen

Publications and source records attributed to Wei Chen.

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

[Expression of NF-kappaB/IkappaB signal pathway in renal tissues of hepatitis B virus-associated nephritis].

AIM: To investigate the expression of nuclear transcription factor-kappa B (NF-kappaB)/IkappaB in renal tissues of hepatitis B virus-associated nephritis (HBVGN) and to study its role in the pathogenesis of HBVGN. METHODS: The expression of NF-kappaB p65 and IkappaB-alpha in renal tissues was examined in biopsy specimens from 42 HBVGN patients, 20 patients with primary membranous nephropathy and 5 normal subjects by immunohistochemical staining. RESULTS: The NF-kappaB p65 expression in glomerular and tubular of HBVGN tissues was notably higher than that in normal control tissues (P<0.05) and in primary membranous nephropathy tissues (P<0.01). The IkappaB-alpha expression in glomerular and tubular of HBVGN tissues was lower than that in primary membranous nephropathy tissues (P<0.05). CONCLUSION: There might be protein degradation of IkappaB-alpha and nuclear translocation of NF-kappaB in renal tissues of HBVGN, which suggests that NF-kappaB/IkappaB signal pathway may play an important role in the pathogenesis of HBVGN.

Adolescent↗
PubMed2006

[Expression of matrix metalloproteinases and their inhibitors in fetal skin and their biological significance].

OBJECTIVE: To investigate the expression characteristics of matrix metalloproteinases (MMP-2, MMP-3, MMP-9) and tissue inhibitor of metalloproteinase (TIMP-1, TIMP-2) in developing fetal skin and their potential biological significance. METHODS: Skin of 24 cases of fetuses with different gestational age (12-40 weeks) were obtained, embedded with paraffin wax, and sectioned. Immunohistochemistry and pathological methods were used to detect the expression intensity and distribution of MMP-2, MMP-3, MMP-9, TIMP-1 and TIMP-2. RESULTS: Positive immunohistochemical signals of MMPs and TIMPs could be found in fetal skin at different gestational periods. These proteins mainly located in the cytoplasm of epidermal cells, fibroblasts, epithelial cells of hair follicles and sweat glands and vascular endothelial cells. In earlier gestational fetal skin (12-18 weeks), the expression levels of MMP-2, MMP-3 and MMP-9 were high. Along with the advancement in gestational age, the positive rates of these three proteins in skin were lowered, and in later gestational fetal skin (27-40 weeks) the expression rates were significantly decreased compared with those in earlier gestational fetal skin (all P<0.05). On the contrary, protein expression levels of TIMP-1 and TIMP-2 were apparently lower in earlier versus later gestational skin (both P<0.05). CONCLUSION: MMP-2, MMP-3, MMP-9, TIMP-1 and TIMP-2 might be involved in the skin development and maintenance of cutaneous structure and function. Higher expression of MMP-2, MMP-3 and MMP-9 and lower protein levels of TIMP-1 and TIMP-2 may provide an antiscarring signal in healing of wound during early periods of gestation.

Fetus↗
PubMed2006

[The change of HBV nucleotide sequence during Adefovir dipivoxil treatment].

OBJECTIVE: To study the change of HBV nucleotide sequence during Adefovir dipivoxil treatment. METHODS: Serum samples were collected from 4 patients (numbers 228, 229, 230 and 233) with chronic hepatitis B (CHB) treated with PMEA. PCR amplification of full-length genomes, total genome clone, and sequencing and linkage of the HBV viruses were done with the serum samples collected before the therapy, and again on the 28th week, 52nd week and on the 92nd week of the therapy. Gene types and serum types were studied according to the HBV DNA sequence. The related biological information was analyzed, including the homogeneity and heterogeneity of the HBV DNA sequence before and during PMEA therapy, and variance of amino acids coded by HBV sequence. RESULTS: The gene types and serum types of HBV of the 4 patients were determined. Patient 228 was gene type C/serum type adrq+. Patient 229 was complex gene type B and C/complex serum type adw2 and adrq+. Patients 230 and 233 were both serum type adw2. The homogeneity of total gene sequence was 97.5% - 99.8% in one group of patients and 90.6% - 100% between groups in variant patients. The base mutation quantity of 52W was significantly higher than that of 28W and 92W. There was a common site of hotspot congregating mutation that existed in the P region. The target of PMEA was located in the P region encoding reverse transcriptase, which was generally very conservative. Therefore the mutations in this region were very significant. This might affect the activity of reverse transcriptase, leading to resistance to PMEA. CONCLUSION: We discovered some unusual aminophenol variations in the HBV genomes, which most probably are related to the HBV mutation that resulted in the developing resistance to PMEA.

Adenine↗
PubMed2006

[Relationship between the proliferation and immunoinduction of epithelial cells and the destruction of hair follicles and sebaceous glands in keloids].

OBJECTIVE: To investigate the influence of biological behavior of epithelial cells on the hair follicles and sebaceous glands (HFSG) structure in keloids (K). METHODS: The expression of intercellular adhesion molecule (ICAM)-1, D-related human leucocyte antigen (HLA-DR), and cytokeratin (CK) 14 on epithelial cells and the amount of activity T-lymphocytes were detected in specimens of keloid edge and normal skin with immunohistochemical and histological methods. RESULTS: In comparison with normal skin specimens, epithelial cells were proliferated in K-HFSG presented structural aberration and disintegrate or abnormally to form solid-epithelial island-like structure, and the density of HSFG with hyperplasia and the ageing scar in keloids was apparently decreased. They strongly expressed ICAM-1, HLA-DR, and CK14 in the epithelial cells, there were many immunologic cells which expressed CD4, CD45RO, and interferon (IFN)-gamma around the K-HFSG. The expressed level of epithelial cells was positively correlated with the density of immunologic cells nearby K-HFSG. CONCLUSION: It could be concluded that the reactivity with hyperplasia and immunoinduction of epithelial cells might be associated with the destruction of the some HFSG structure in the keloids.

Adolescent↗
PubMed2006

18F-FDOPA PET imaging of brain tumors: comparison study with 18F-FDG PET and evaluation of diagnostic accuracy.

UNLABELLED: We evaluated the amino acid and glucose metabolism of brain tumors by using PET with 3,4-dihydroxy-6-(18)F-fluoro-l-phenylalanine ((18)F-FDOPA) and (18)F-FDG. METHODS: Eighty-one patients undergoing evaluation for brain tumors were studied. Initially, 30 patients underwent PET with (18)F-FDOPA and (18)F-FDG within the same week. Tracer kinetics in normal brain and tumor tissues were estimated. PET uptake was quantified by use of standardized uptake values and the ratio of tumor uptake to normal hemispheric tissue uptake (T/N). In addition, PET uptake with (18)F-FDOPA was quantified by use of ratios of tumor uptake to striatum uptake (T/S) and of tumor uptake to white matter uptake. The accuracies of (18)F-FDOPA and (18)F-FDG PET were determined by comparing imaging data with histologic findings and findings of clinical follow-up of up to 31 mo (mean, 20 mo). To further validate the accuracy of (18)F-FDOPA PET, (18)F-FDOPA PET was performed with an additional 51 patients undergoing brain tumor evaluation. RESULTS: Tracer uptake in tumors on (18)F-FDOPA scans was rapid, peaking at approximately 15 min after intravenous injection. Tumor uptake could be distinguished from that of the striatum by the difference in peak times. Both high-grade and low-grade tumors were well visualized with (18)F-FDOPA. The sensitivity for identifying tumors was substantially higher with (18)F-FDOPA PET than with (18)F-FDG PET at comparable specificities, as determined by simple visual inspection, especially for the assessment of low-grade tumors. Using receiver-operating-characteristic curve analysis, we found the optimal threshold for (18)F-FDOPA to be a T/S of greater than 1.0 (sensitivity, 96%; specificity, 100%) or a T/N of greater than 1.3 (sensitivity, 96%; specificity, 86%). The high diagnostic accuracy of (18)F-FDOPA PET at these thresholds was confirmed with the additional 51 patients (a total of 81 patients: sensitivity, 98%; specificity, 86%; positive predictive value, 95%; negative predictive value, 95%). No significant difference in tumor uptake on (18)F-FDOPA scans was seen between low-grade and high-grade tumors (P = 0.40) or between contrast-enhancing and nonenhancing tumors (P = 0.97). Radiation necrosis was generally distinguishable from tumors on (18)F-FDOPA scans (P < 0.00001). CONCLUSION: (18)F-FDOPA PET was more accurate than (18)F-FDG PET for imaging of low-grade tumors and evaluating recurrent tumors. (18)F-FDOPA PET may prove especially useful for imaging of recurrent low-grade tumors and for distinguishing tumor recurrence from radiation necrosis.

Adult↗
PubMed2006

[Assessment on the ability of emergency response at the county center for disease control and prevention level in flooding-prone areas].

OBJECTIVE: To establish a comprehensive assessment model on the ability of emergency response within the public health system in flooding-prone areas. METHODS: A hierarchy process theory was used to establish the initial assessing framework. Delphi method was used to screen and choose the ultimate indicators and their weights before an assessment model was set up under the 'synthetic scored method' to assess the ability of the emergency response among twenty county public health units. We then used the 'analysis of variation (ANOVA)' methodology to test the feasibility of distinguishing the ability of emergency response among different county health units and correlation analysis was used to assess the independence of indicators in the assessing model. RESULTS: A comprehensive model was then established including twenty first-class indicators and fifty-six second-class indicators and the degree of ability to emergency response with flooding of public health units was evaluated. There were five public health units having higher, ten having moderate but five with lower levels on emergency response. The assessment model was proved to be a good method in differentiating the ability of public health units, using independent indicators. CONCLUSION: The assessment model which we established seemed to be practical and reliable.

Analysis of Variance↗
PubMed2006

[Cytotoxicity of cytotoxic T lymphocytes induced by the dendritic cells phagocytosing PLA-AFP218-226 micospheres Against hepatocellular carcinoma cell lines].

OBJECTIVE: To assess the cytotoxicity of cytotoxic T lymphocytes (CTLs) induced by the dendritic cells phagocytosing HLA-A2+ restricted epitope peptides encapsulated in polylactic acid (PLA) microspheres (PLA-AFP218-226) against cell lines HepG2 and T2-loaded with HLA-A2+ restricted epitope peptides derived from alpha fetoprotein (AFP218-226, LLNQHACAV). METHODS: Mature dendritic cells (DCs) were obtained by inducing the monocytes isolated from peripheral blood cells of HLA-A2+ healthy donors with GM-CSF and IL-4. On day 3 from onset of the culture, PLA- AFP218-226 was added to the culture medium, and on day 6, lipoplysaccharide (LPS) was added to it for inducing the immature DCs to mature. The surface phenotype of the mature DCs was determined with fluorescence activated cell sorting (FACS) assay; the cytotoxicity of CTLs induced by the DCs for 7 days against cell lines HepG2 and T2-loaded with AFP218-226 was determined with MTT method; and the avidity between HLA-A2 and AFP218-226 was determined with T2-peptide binding experiment. RESULTS: There was high avidity between AFP218-266 and HLA-A2. The DCs phagocytosing PLA-AFP218-226 highly expressed CD83, CD86, CD40, etc., and the CTLs induced by the DCs strongly decomposed the HepG2 and T2-loaded with AFP218-226. CONCLUSIONS: The strong cytotoxicity against HepG2 cell lines can be induced in vitro by DCs phagocytosing PLA-AFPM218-226 micospheres, suggesting that PLA-AFP218-226 microspheres can serve as a new type of CTL epitope vaccine for the prophylaxis and treatment of hepatocellular carcinoma.

Carcinoma, Hepatocellular↗
PubMed2006

[An application of laser capture microdissection to isolate the pure atrial cells].

OBJECTIVE: To use the laser capture microdissection (LCM) to isolate the pure atrial cells from heart. To extract tiny amount RNA and amplify the genes of beta-actin and GAPDH. METHODS: First, the prepared sample RNA was extracted and verified. Second, the frozen sections were scraped after haematoxylin-eosin staining, and then the RNA of scraped tissues was extracted and verified. Last, the tiny amount RNA was extracted from atrial cells captured by LCM, and the genes of beta-actin and GAPDH were amplified by reverse transcriptase polymerase chain reaction (RT-PCR). RESULTS: The atrial cells isolated with LCM had clear morphology after quick staining. The high quality RNA was extracted from LCM sample and scraped tissues, of which A260/A280 was 1.9-2.0. And 18S rRNA and 28S rRNA were seen distinctly on the gel of RNA formaldehyde denaturing gel electrophoresis, which indicated that RNA didn't degrade before cells captured. Too small amount of RNA extracted from captured cells was below the detectable limit of gel electrophoresis or ultraviolet spectrophotometer. Bands of 300 bp and 357 bp could be amplified by RT-PCR from tiny amount RNA. CONCLUSION: Highly pure atrial cells could be obtained by LCM. Tiny amount RNA of captured atrial cells could be extracted and amplified with genes of beta-actin and GAPDH.

Actins↗
PubMed2006

[Effects of the HLA antibodies on allograft acute rejection after cadaveric liver transplantation].

OBJECTIVE: To evaluate the effect of perioperative HLA antibody changes on acute allograft rejection in cadaveric liver transplantation. METHODS: Totally 134 patients received modified piggyback liver transplantation and enzyme-linked immunosorbent assay was performed for HLA antibody detection before and the 1, 7, 14 and 30 days after operation. B ultrasound-guided liver biopsy was employed for diagnosis of acute allograft rejection, and the perioperative changes of HLA antibodies were evaluated for their effect on allograft acute rejection. RESULTS: Of the 44 recipients with preoperative positivity for HLA antibodies, acute rejection occurred in 56.8% of the patients, as compared with 25.9% in those negative for HLA antibody (P=0.001). The patients who became positive for HLA antibody postoperatively had a rate of acute rejection of 60%, which was significantly higher than that in those persistently negative for HLA antibody (18.6%, P=0.003). CONCLUSION: HLA antibody positivity before transplantation may contribute to acute rejection episode in liver transplantation, and persistent posttransplant HLA antibody positivity is closely associated with the occurrence of acute rejection.

Adult↗
PubMed2006

[Misdiagnosis and mistherapy of ectopic thyroid gland].

OBJECTIVE: To explore the clinic characteristic, diagnosis and treatment of ectopic thyroid gland (ETG) and avoid the misdiagnosis and mistherapy of ETG. METHOD: The clinic materials of 4 cases with ETG were analysed. Four patients were misdiagnosed thyroglossal duct cyst. The clinical features, diagnosis and management of ETG were discussed. RESULT: All of patients had a normal thyroid gland in the neck and underwent a surgical resection of neck mass. Postoperative pathologic examination revealed the neck masses originated from accessory thyroid gland, of them, 1 gland enlargement, 1 adenoma and 2 adenocarcinoma. Fortunately, by the postoperative fellow up, no significant complication was found in the patients. CONCLUSION: The well understanding of ETG and the detailed examination before surgical treatment of neck mass, including ultrasonography, CT or MRI, radioactive isotope scanning and fine needle aspiration biopsy, are keys to adequate diagnosis and management of ETG.

Adult↗
PubMed2006

Gene expression changes after hypoxic preconditioning in rat hepatocytes.

BACKGROUND: Hypoxic preconditioning can protect hepatocytes against hypoxic injury, but its mechanism has not been elucidated. The aim of this study was to profile gene expression patterns involved in hypoxic preconditioning and probable mechanism at the level of gene expression. METHODS: Hepatocytes were divided into 2 groups: control group and hypoxic preconditioning group. Biotin-labeled cRNA from the control group and the hypoxic preconditioning group was hybridized by oligonucleotide microarray. Genes that were significantly associated with hypoxic preconditioning were filtered, and validated at the level of transcript expression. RESULTS: Forty-three genes with significantly altered expression patterns were discovered and most of them had not been previously reported. Among these genes, genes encoding superoxide dismutase 2 (SOD2) and interleukin 10 (IL-10) in the hypoxic preconditioning group were confirmed to be up-regulated with real-time quantitative PCR. CONCLUSIONS: Many cytokines are involved in hypoxic preconditioning and protect hepatocytes from hypoxia-reoxygenation injury, and the increase of oxygen free-radical scavengers and anti-inflammatory factors may play a key role in this phenomenon. Diverse signal pathways are probably involved.

Animals↗
PubMed2006

Racial (black-white) contrasts of risk for hypertensive disease in youth have implications for preventive care: the Bogalusa Heart Study.

Cardiovascular (CV) diseases remain the major cause of illness and death in the United States. Adverse CV outcomes are influenced by race/ ethnicity and sex. Race and sex contrasts of CV risk factors become evident early in life and have implications for prevention and medical care. Changes in the CV system in hypertensive disease are mediated by interplay among body fatness, insulin sensitivity, and other factors such as renin-angiotensin system and electrolyte homeostasis. Observations from the Bogalusa Heart Study found higher blood pressure levels in Black children even without obesity, renin as a component of the metabolic/insulin resistance syndrome mainly in Whites, and Black-White differences in electrolyte handling, eg, lower urinary excretion of potassium in Blacks. Understanding divergences in hemodynamic and metabolic parameters for developing hypertensive disease can help improve approaches to beginning prevention at an early age. The use of low doses of antihypertensive medications along with prudent diet and physical activity may be considered for children with elevated blood pressure.

Adolescent↗
PubMed2006

[Cloning and expression analysis of human N-acetyltransferase doman containing gene hNATL].

A novel human gene hNA TL (Human NAT Like) was cloned by in silico cloning and RT-PCR. hNA TL cDNA is 1803bp in length with a 621bp coding region, and the Genbank accession No. is AY632082. hNA TL encodes a protein of 206 amino acid residues which containing a N-acetyltransferase domain. hNA TL is located on human chromosome 17q25.2 with 6 exons. Serial analysis of gene expression revealed that hNA TL was highly expressed in human brain and gonad, while hNA TL was expressed in heart, spleen and gonad of adult mouse. Whole-mount in situ hybridization showed that hNATL specifically expresses in E7.5 and E8.5 mouse embryo brains and in HH10 stage chicken embryo brain. These results suggest that hNATL may play an important role in the development of embryo brain and may also be important for function of adult brain and gonad.

Acetyltransferases↗
PubMed2006

[Differential expression of immune-associated genes in two subcloned cell lines from a same human bladder cancer].

AIM: To screen and identify differentially expressed genes in subcloned lines from a same human bladder transitional cell carcinoma (TCC). METHODS: Two bladder TCC cell lines (BLX and BLS-211) with different phenotypes but same origin were used to screen for differentially expressed genes by suppression subtractive hybridization (SSH). RESULTS: 9 over-expressed genes in BLX and 15 in BLS-211 cells were obtained, respectively. Some Bacillus Galmette-Guerin(BCG)- associated genes, such as BCG induced integral membrane protein(BIGM103), fibronectin(FN), complement factor B(BF), were over-expressed in BLX cells. And 8 new ESTs(Expressed Sequence Tag) in BLS-211 cells were collected by GenBank dbEST database with the accession number of DY505708-13, DY230447-8. CONCLUSION: SSH is a powerful method for the identification of differentially expressed genes in different cell lines or clones. Some BCG-associated genes, which are differentially expressed in different cells may contribute to the different response to clinical BCG therapy. The identified new ESTs can be cloned for full length to further study their functions.

Carcinoma, Transitional Cell↗
PubMed2006

Dependence of cardiac 11C-meta-hydroxyephedrine retention on norepinephrine transporter density.

UNLABELLED: The norepinephrine analog (11)C-meta-hydroxyephedrine (HED) is used with PET to map the regional distribution of cardiac sympathetic neurons. HED is rapidly transported into sympathetic neurons by the norepinephrine transporter (NET) and stored in vesicles. Although much is known about the neuronal mechanisms of HED uptake and retention, there is little information about the functional relationship between HED retention and cardiac sympathetic nerve density. The goal of this study was to characterize the dependence of HED retention on nerve density in rats with graded levels of cardiac denervation induced chemically with the neurotoxin 6-hydroxydopamine (6-OHDA). METHODS: Thirty male Sprague-Dawley rats were divided into 6 groups, and each group was administered a different dose of 6-OHDA: 0 (controls), 7, 11, 15, 22, and 100 mg/kg intraperitoneally. One day after 6-OHDA injection, HED (3.7-8.3 MBq) was injected intravenously into each animal and HED concentrations in heart and blood at 30 min after injection were determined. Heart tissues were frozen and later processed by tissue homogenization and differential centrifugation into a membrane preparation for in vitro measurement of cardiac NET density. A saturation binding assay using (3)H-mazindol as the radioligand was used to measure NET density (maximum number of binding sites [B(max)], fmol/mg protein) for each heart. RESULTS: In control animals, NET B(max) was 388 +/- 23 fmol/mg protein and HED heart uptake (HU) at 30 min was 2.89% +/- 0.35 %ID/g (%ID/g is percentage injected dose per gram tissue). The highest 6-OHDA dose of 100 mg/kg caused severe cardiac denervation, decreasing both NET B(max) and HED HU to 8% of their control values. Comparing values for all doses of 6-OHDA, HED retention had a strong linear correlation with NET density: HU = 0.0077B(max) -0.028, r(2) = 0.95. CONCLUSION: HED retention is linearly dependent on NET density in rat hearts that have been chemically denervated with 6-OHDA, suggesting that HED retention is a good surrogate measure of NET density in the rat heart. This finding is discussed in relation to clinical observations of the dependence of HED retention on cardiac nerve density in human subjects using PET.

Animals↗
PubMed2006

[Clinical analysis of PLI, GI and SBI in patients with fixed orthodontic appliances].

PURPOSE: The aim of the present study was to carry out a detailed analysis of the data on PLI, GI, SBI in fixed orthodontic patients. METHODS: 375 middle school students aged 12 to 15 years old were selected as control group, including 196 boys and 179 girls. 331 patients with fixed orthodontic appliances aged 12 -15 years from city were used as experimental group, including 101 boys and 230 girls without mouth-breathing. Gingival index (GI), sulcus bleeding index (SBI), and plaque index (PLI) were recorded for each individual patient six months after being with orthodontic appliances. Four upper and four lower incisors were assessed, the data of the two groups were analyzed with SPSS 10.0 software package for Student's t test. RESULTS: It was found that there were significant higher PLI, GI and SBI values in orthodontic treated patients (P<0.01). Although there was no significantly difference in PLI value between boys and girls (P>0.05) in the experimental group, there were statistically significant higher GI and SBI values compared boys with girls (P<0.01). There were significantly higher PLI and GI values in boys' lower incisor(P<0.01). Oral health care was difficult in patients with fixed orthodontic appliances. Boys' oral hygiene was poorer than girls'. CONCLUSION: In order to maintain periodontal health, it is very important to strengthen oral hygiene to children who receive fixed appliance, especially in boys, as well as control the level of plaque accumulation in the lower incisors.

Adolescent↗