Biomedical subjects

Ye Zhang

Publications and source records attributed to Ye Zhang.

At least 73 records · Page 4Linked to original sources

PubMed2004

[Enhanced action of a BTB/POZ domain protein on the expression of hsp90alpha gene in heat shock].

OBJECTIVE: To study the role of a BTB/POZ domain protein in the expression of hsp90alpha gene. METHODS: The eukaryotic expression plasmids of sense- and antisense-GAGA related protein (GRP) or empty vector were transfected into Jurkat cells with pREP4 episomal vector plasmids carrying the hsp90alpha promoter sequence from -1756 to +37 and control plasmids pMCAT. Total RNA was extracted. The relative promoter activity of hsp90alpha-CAT reporter gene was determined by competitive RT-PCR assay. RESULTS: GRP markly increased the relative promoter activity of hsp90alpha-CAT reporter gene during heat shock. CONCLUSION: GRP may promote the expression of hsp90alpha gene by participating in chromatin remolding.

Amino Acid Motifs↗

PubMed2004

[Changes of fasting serum insulin in normotensive patients with left ventricular hypertrophy].

OBJECTIVE: To explore the relationship between left ventricular hypertrophy (LVH) and serum insulin changes in normotensive patients. METHODS: Forty-two normotensive patients with LVH, who were free of hypertension, coronary artery disease and diabetes, were examined for fasting serum insulin, glucose and serum lipids, and the left ventricular mass (LVM) and left ventricular mass index (LVMI) were also measured with echocardiography, with 46 normal subjects serving as the control group. RESULTS: The levels of fasting triglyceride and insulin, as well as insulin resistance index (IRI), were higher in the LVH group than in the control group. Multifactor regression analysis showed that IRI was positively correlated to LVM and LVMI in LVH group (r=0.38, P<0.01; r=0.29, P<0.01). CONCLUSION: Hyperinsulinemia is closely correlated with LVH in these normotensive patients, and can be involved in the pathogenesis and progression of LVH.

Aged↗

PubMed2004

[Application of 99mTc(V)-dimercaptosuccinic acid imaging in detecting neck metastases in patients with oral squamous cell carcinoma].

OBJECTIVE: To evaluate the applicability of 99mTc(V) -dimercaptosuccinic acid (99mTc (V) -DMSA) imaging in detecting neck metastases in patients with oral squamous cell carcinoma. METHODS: Single photon emission computer tomography (SPECT) scintigraphy with 99mTc(V) -DMSA was performed on 32 patients with primary squamous cell carcinoma in oral cavity. The coronal aspect of SPECT image was chosen, the region of interest (ROI) of the affected neck was drawn, and the radioactivity uptake value of the ROI was given by the computer to compare with the contralateral neck. The results of 99mTc(V) -DMSA were compared with postoperative pathological studies. For false positive lymph nodes, semi-continuous slice was carried out for pathology examination. RESULTS: The sensitivity, specificity and accuracy of 99mTc(V) -DMSA imaging for detecting metastatic lymph nodes were 75.0%, 90.0% and 84.4% respectively. The ROI values of the affected neck are higher than that of the contralateral part in the 9 positive patients (t = 8.128, P = 0.000 04). Metastasis was not found in the enlarged lymph nodes of the false positive patients. CONCLUSIONS: 99mTc(V) -DMSA SPECT imaging has fairly high affinity with metastatic lymph nodes in the neck especially in the cN0 patients and is helpful for designing proper neck dissection.

Adult↗

PubMed2004

[Heat shock induced transcription of hsp90alpha gene on chromatin template].

OBJECTIVE: A CAT reporter plasmid (pBLCAT3alpha1) driven by the promoter of hsp90alpha was in vitro assembled into chromatin to investigate the transcription activity of the reporter gene upon heat shock. METHODS: A competitive RT-PCR-based technique was used to quantify the promoter activity of hsp90alpha gene on chromatin or naked DNA templates in vitro. RESULTS: The in vitro transcription efficiency was first optimized by using different amounts of whole cell extracts from heat shock-treated HeLa cells. In vitro chromatin assembly was carried out with purified components of chromatin assembly associated factors, core histones and CAT reporter gene driven by the promoter of hsp90alpha gene. Results showed that chromatin formation repressed the in vitro transcription of the gene. CONCLUSION: The heat shock induced transcription of hsp90alpha gene on chromatin template is more efficient than that on naked DNA in vitro.

Chromatin Assembly and Disassembly↗

PubMed2004

[Reconstruction of accessory nerve defects with sternocleidomastoid muscle-great auricular nerve flap].

OBJECTIVE: To describe a new method of accessory nerve defect reconstruction with sternocleidomastoid muscle-great auricular flap. METHODS: Thirty-four cases receiving traditional radical neck dissection were divided into two groups: single neck dissection group (n = 19) and accessory nerve reconstruction group (n = 15). Surgical procedure of the reconstruction was described in detail. Postoperative shoulder functions were compared between the two groups. RESULTS: Accessory nerve reconstruction group experienced much better shoulder function recovery than that in single neck dissection group. CONCLUSIONS: Reconstruction of accessory nerve defects with sternocleidomastoid muscle-great auricular nerve flap is simple, effective and complication-free.

Accessory Nerve↗

PubMed2003

Elongation by RNA polymerase II on chromatin templates requires topoisomerase activity.

Transcription on chromatin by RNA polymerase II (pol II) is repressed as compared with transcription on histone-free DNA. In this study, we show that human topoisomerase I (topo I) and yeast topoisomerase II (topo II), each of which relax both positive and negative superhelical tension, reverse the transcriptional repression by chromatin. In the presence of bacterial topo I, which can relax only negative superhelical tension, the transcription is repressed on chromatin templates. The data together show that the relaxation of positive superhelical tension by these enzymes was the key property required for RNA synthesis from chromatin templates. In the absence of topoisomerase, transcriptional repression on chromatin depended on RNA length. The synthesis of transcripts of 100 nt or shorter was unaffected by chromatin, but repression was apparent when the RNA transcript was 200 nt or longer. These findings suggest that transcription on chromatin templates results in the accumulation of positive superhelical tension by the elongating polymerase, which in turn inhibits further elongation in the absence of topoisomerase activity.

Camptothecin↗

PubMed2003

The use of fluorescence resonance energy transfer to monitor dynamic changes of lipid-DNA interactions during lipoplex formation.

Fluorescence resonance energy transfer (FRET) was used to monitor interactions between Cy3-labeled plasmid DNA and NBD-labeled cationic liposomes. FRET data show that binding of cationic liposomes to DNA occurs immediately upon mixing (within 1 min), but FRET efficiencies do not stabilize for 1-5 h. The time allowed for complex formation has effects on in vitro luciferase transfection efficiencies of DOPE-based lipoplexes; i.e., lipoplexes prepared with a 1-h incubation have much higher transfection efficiencies than samples with 1-min or 5-h incubations. The molar charge ratio of DOTAP to negatively charged phosphates in the DNA (DOTAP+/DNA-) also affected the interaction between liposomes and plasmid DNA, and interactions stabilized more rapidly at higher charge ratios. Lipoplexes formulated with DOPE were more resistant to high ionic strength than complexes formulated with cholesterol. Taken together, our data demonstrate that lipid-DNA interactions and in vitro transfection efficiencies are strongly affected by the time allowed for complex formation. This effect is especially evident in DOPE-based lipoplexes, and suggests that the time allowed for lipoplex formation is a parameter that should be carefully controlled in future studies.

Carbocyanines↗

PubMed2003

Molecular cloning and characterization of LAPTM4B, a novel gene upregulated in hepatocellular carcinoma.

Lysosomal-associated protein transmembrane-4 beta (LAPTM4B), a novel gene upregulated in hepatocellular carcinoma (HCC), was cloned using fluorescence differential display, RACE, and RT-PCR. It contains seven exons and encodes a 35-kDa protein with four putative transmembrane regions. Both the N- and C-termini of the protein are proline-rich, and may serve as potential ligands for the SH3 domain. Immunohistochemical analysis localized the protein predominantly to intracellular membranes. Northern blot showed that the LAPTM4B mRNAs were remarkably upregulated in HCC (87.3%) and correlated inversely with differentiation status. LAPTM4B was also overexpressed in many HCC-derived cell lines. It was also highly expressed in fetal livers and certain adult normal tissues including the heart, skeletal muscle, testis, and ovary. Promoter function assays showed a distinct difference in the gene's activities between BEL7402 and HLE cell lines, suggesting that the transcription factors responsible for regulation of the gene in the two cell lines are different, and that possible negative regulatory cis-elements may exist upstream of the promoter region. It was demonstrated that the N-terminus of LAPTM4B was essential for survival of the cells. Cells harboring the full-length LAPTM4B cDNA expression clone displayed a slightly increased efficiency in colony formation. These results suggest that LAPTM4B is a potential protooncogene, whose overexpression is involved in carcinogenesis and progression of HCC. In normal cells, it may also play important roles such as regulation of cell proliferation and survival.

Adult↗

PubMed2003

Enhanced production of amyloid precursor protein mRNA by peripheral mononuclear blood cell in Alzheimer's disease.

Previous studies have suggested the involvement of amyloid precursor protein (APP) in Alzheimer's disease (AD), as exons 16 and 17 of the APP gene mutations have been found in some familial AD patients. Furthermore, overexpression and deposition of the beta amyloid peptide, a proteolytic product of APP, have been considered as a pathological hallmark of Alzheimer's disease. Therefore, it is of particular interest to determine the expression of APP gene at the transcription level for better understanding of the roles of APP gene in AD pathogenesis. In this work, we employed the quantitative reverse transcriptase-polymerase chain reaction (RT-PCR) to quantify APP mRNA transcripts in the peripheral mononuclear blood cells (PMBC) of 52 Alzheimer's patients, 28 vascular dementia (VD) patients, and 60 healthy elderly controls. The results showed that the amount (mean +/- SEM) of APP transcripts per microgram of total cDNA was 4.05 +/- 0.27, 2.73 +/- 0.33, and 2.59 +/- 0.27 amole in AD, VD, and healthy controls, respectively. There was a significant increase (P < 0.05) in the expression of APP mRNA transcripts in AD compared with that in VD or in healthy controls. Thus, our data indicated that variation of APP gene expression in PMBC might be a pathogenic source of Alzheimer's disease.

Aged↗

PubMed2003

Negative role of cAMP-dependent protein kinase A in RANTES-mediated transcription of proinflammatory mediators through Raf.

The chemokine RANTES (regulated on activation normal T cell expressed and secreted) is expressed in several inflammatory diseases of the central nervous system and is a powerful stimulus for astrocyte production of proinflammatory mediators. The mechanism of RANTES-mediated astrocyte activation was investigated. RANTES stimulation decreased both intracellular cyclic AMP (cAMP) levels and cAMP-dependent protein kinase A (PKA) activity in cultures of primary mouse astrocytes. H-89, a potent inhibitor of PKA, mimicked RANTES-mediated chemokine and cytokine transcription. RANTES treatments activated Raf-1 kinase activity, and conversely a dominant negative Raf and a Raf-1 inhibitor blocked RANTES-induced chemokine transcription. Transfection with a constitutively active Raf was sufficient to induce transcription of proinflammatory mediators. The combined data indicate that Raf-1 is required for RANTES-mediated astrocyte activation. Decreases of cAMP and PKA activity contributed to the transcription of proinflammatory mediators by cross-talk with the Raf-1/mitogen-activated protein kinase pathway. The results identify an upstream signaling pathway for amplification of proinflammatory mediators in the central nervous system.

Animals↗

PubMed2003

A comparative study and phage typing of silage-making Lactobacillus bacteriophages.

To investigate basic characteristics of 10 virulent phages active on silage-making lactobacilli, morphological properties, host ranges, protein composition and genome characterization were separated into five groups based on host ranges and basic properties. The seven phages of groups I, II and V were active on Lactobacillus plantarum and Lactobacillus pentosus. Phage phiPY4 (group III) infected both L. casei and Lactobacillus rhamnosus. Phage phiPY5 (group IV) specifically infected Lactobacillus casei. Morphologically, three phages of groups I belonged to the Myoviridae family, while seven other phages of groups II, III and V belonged to the Siphoviridae family. SDS-PAGE profiles, restriction analysis, G + C contents of DNA and Dot blot hybridization revealed a high degree of homology in each group. Clustering derived from host range analysis was closely related to results of DNA and protein analyses. These phages may be applicable to phage typing for silage-making lactobacilli.

Journal Article↗

PubMed2003

[Influenza activity in China from 2000 to 2001].

OBJECTIVE: To understand the epidemics and antigenic drift of influenza viruses in China from 2000 to 2001. METHODS: The viruses were grown in embryonated hen eggs with 9 - 10 days old. The egg allantoic fluids with influenza viruses were used. Virion RNA was transcribed into cDNA by reverse transcriptase while cDNA amplified by PCR. Products of PCR were purified. RNA sequence analysis was then performed. Finally, phylogenetic analysis of the sequencing data was performed with MegAlign (Version 1.03) and Editseq (Version 3.69) software. RESULTS: Data from comparison of amino acid sequence on HA1 domain of HA protein molecule between H1N1 viruses isolated in 2001 and A/Shanghai/7/99 (H1N1) strain indicated that there was only one difference of amino acid located at 190 position (antigenic determinant D). However, phylogenetic analysis showed that there were two distinguishable genetically lineages of H1N1 viruses co-circulating in men in China in 2001. Two antigenically distinct genetic lineages of influenza B viruses were still existing in men in China. Most of influenza B viruses were Yamagata-like strain and there were two different amino acid sequences located at 197 and 199 position on HA1 domain of HA protein molecule, between Victoria-like virus isolated and B/Shandong/7/97 strain. When comparing amino acid sequences on HA1 protein domain of H3N2 viruses isolated in 2000 with those of A/Sydeney/5/97 (H3N2) virus, it was revealed that there were 7 - 8 differences of amino acid sequences between them. However, there were four differences related to amino acid sequences on HA1 protein domain between H3N2 viruses isolated in 2000 and in 2001. These results were further demonstrated by analysis of phylogenic tree. CONCLUSIONS: Influenza was not prevalent in China from 2000 to 2001. The antigenic drifts of H3N2 and B/Victoria-like viruses occurred. Two antigenically distinct genetic lineages of influenza B viruses were still co-circulating in men in China. Two genetically distinct lineages of influenza A (H1N1) virus were also co-circulating in men in China.

Antigens, Viral↗

PubMed2003

[Surgical anatomy and preservation of the accessory nerve in radical functional neck dissection].

OBJECTIVE: The surgical anatomy and preservation of the accessory nerve in radical functional neck dissection were studied. METHODS: Thirty-three cN(0) patients with oral cancers were entered into the study. Radical functional neck dissection were performed and the relations between the accessory nerve and its surrounding structures were recorded. RESULTS: The accessory nerve going through or beneath the sternocleidomastoid muscle occurred in 82% (27/33) and 18% (6/33) of the patients respectively. Communicating branches between the accessory and the cervical nerves were found in 85% (28/33). There was 2 to 3 cm of the accessory nerve paralleled to the anterior border of the trapezius muscle before it entered the muscle in 70% (23/33). The dissection of the nerve needed 20 to 30 minutes. Twenty-seven percent of the patients had pathologically proved lymph node metastases. CONCLUSIONS: Looking for accessory nerve under the upper portion of the sternocleidomastoid muscle and above the middle point of the muscle posterior border is simple and safe. The point of the great auricular nerve going out the muscle is an important indicator for finding the accessory nerve.

Accessory Nerve↗

PubMed2003

Myoepithelial carcinoma of the salivary glands: behavior and management.

OBJECTIVE: To investigate the biological behavior and proper management of myoepithelial carcinomas of salivary glands. METHODS: Twenty-seven cases of myoepithelial carcinoma of salivary glands were retrospectively studied and their detailed clinical and follow-up data were presented. RESULTS: The subjects consisted of 17 men and 10 women aged 16 to 73 years (mean age: 51 years). The parotid gland was the most common site (n = 14) of cancer. Clinical features included extensive local growth, invasion of the surrounding tissues, infrequent cervical lymph node metastasis but high rates of distant metastasis, frequent/multiple recurrences and poor prognosis. CONCLUSIONS: Myoepithelial carcinomas of the salivary gland should be classified as high-grade malignancies. Early and radical surgery with close follow-up are essential for achieving favorable outcomes. Radiotherapy appears to be non-sensitive and elective neck dissection is generally unnecessary.

Adolescent↗

PubMed2003

[Antigenic and genetic characterizations of Victoria like strain of influenza B viruses isolated in China in 2001].

BACKGROUND: To understand the antigenic and genetic characteristics of Victoria like strain of influenza B virus isolated recently and to provide a scientific evidence for influenza surveillance and monitoring of influenza epidemic in future. METHODS: Viruses were passed in embryonated hen eggs and virion RNA was extracted from allantoic fluid and reverse transcribed to synthesize cDNA. cDNA was amplified by PCR and the PCR product was purified with a purification kit. Afterwards RNA sequence analysis was performed by dideoxynucleotide chain termination and a cloning method. Finally, phylogenetic analysis of the sequencing data was performed with MegAlign. RESULTS: B/Sichuan/63/2001 and B/Zhejiang/2/2001 viruses were antigenically different from B/Shandong/7/97 strain. The substitution of nucleotide sequences of HA1genes of them compared with those of B/Shandong/7/97strain resulted in the change of amino acid sequences in antigenic determinants on HA1 protein domain. The phylogenetic analysis also indicated that strains isolated recently were genetically different from B/Shandong/7/97/strain. However, there was neither differences on the antigenicity nor genetic partern between these two isotates. CONCLUSIONS: The antigenic drift of Victoria-like strain of influenza B virus isolated recently in China has further occurred.

Amino Acid Sequence↗

PubMed2003

[Association analysis between attention-deficit hyperactivity disorder and Val158Met polymorphism of catechol-O-methyltransferase gene].

OBJECTIVE: To investigate the association between attention-deficit hyperactivity disorder (ADHD) in Han Chinese children and Val158Met polymorphism of catechol-O-methyltransferase (COMT) gene caused by the missense mutation of G158A in exon 4. METHODS: By using polymerase chain reaction-restriction fragment length polymorphisms the Val158Met polymorphism of COMT gene was tested in 117 children with the diagnosis of ADHD as defined by DSM-IV and in 105 healthy controls living in Shanghai. RESULTS: The frequencies of A allele were 25.21% and 23.81% in the ADHD group and the health controls respectively, which showed no significant difference between the two groups (Chi2=0.5197, P>0.05). There was also no significant difference in the distribution of all genotypes of COMT gene between the ADHD patients and the controls (P>0.05). CONCLUSION: It was suggested that for the Han Chinese children with ADHD in this study, there was no association between ADHD and Val158Met polymorphism of COMT gene.

Adolescent↗

PubMed2003

[Identification and characterization of LAPTM4B encoded by a human hepatocellular carcinoma-associated novel gene].

OBJECTIVE: To identify and characterize the novel proteins encoded by a HCC-associated novel gene, LAPTM4B (lysosomeassociated protein transmembrane 4 beta). METHODS: The novel proteins was identified by Western blot, immunohistochemistry and 2D electrophoresis; the molecular interactions were studied by co-immunoprecipitation. RESULTS: LAPTM4B encoded two isoforms of proteins with molecular weight 35 x 10(3) and 24 x 10(3) and pI 9.07 and 4.65, respectively. The expression levels of LAPTM4B proteins in HCC tissues and cell lines were upregulated and related to differentiation, and most dramatically raised for 35 x 10(3) one. It was demonstrated that LAPTM4B--integrin alpha 6 and LAPTM4B--EGFR signaling complexes were formed when BEL-7402 cells were seeded on laminin substrate. CONCLUSION: The LAPTM4B-35 protein is overexpressed in human HCC tissues and cell lines and may involve in signal transduction triggered by extracellular matrix via interaction with integrin alpha 6 and EGFR on cell surface.

Carcinoma, Hepatocellular↗

PubMed2003

[Distraction osteogenesis for correction of maxillo-mandibular deformity].

OBJECTIVE: To study the application of extraoral distraction devices in correction of various maxillo-mandibular deformities. METHODS: From 1997, 11 cases with various maxillo-mandibular deformities were corrected by distraction devices of designed by myself. 7 cases of then were the patients with cleft palate who have severe secondary maxillary hypoplasia. 1 case with micrognathia, 1 case with partial mandibular mentum defect, 1 case with lateral deviation of micrognathia and 1 case with hemimandibular hypertrophy. The mandibles were elongated, from 12 mm to 20 mm, the maxillae were elongated from 7 mm to 22 mm, the vertical mandibular distraction was 15 mm. RESULTS: All cases were corrected satisfactorily and haven't any complications. In 1 cases the 1 Kischners pin had been pull out by loosen during distration. 4 Kischners pin were curved during vertical mandibular distration. Another case the maxillary hypoplasia appeared edge-to-edge and mild open occlusion after 4 weeks fixation. CONCLUSION: The extraoral distration osteogenesis provides a new method with many advantages for those maxillo-mandibular deformities that are difficulty corrected by ordinary orthognathic surgery.

Cleft Palate↗