Biomedical subjects

Jian Sun

Publications and source records attributed to Jian Sun.

At least 37 records · Page 2Linked to original sources

PubMed2006

Generation, annotation, and analysis of an extensive Aspergillus niger EST collection.

BACKGROUND: Aspergillus niger, a saprophyte commonly found on decaying vegetation, is widely used and studied for industrial purposes. Despite its place as one of the most important organisms for commercial applications, the lack of available information about its genetic makeup limits research with this filamentous fungus. RESULTS: We present here the analysis of 12,820 expressed sequence tags (ESTs) generated from A. niger cultured under seven different growth conditions. These ESTs identify about 5,108 genes of which 44.5% code for proteins sharing similarity (E < or = 1e(-5)) with GenBank entries of known function, 38% code for proteins that only share similarity with GenBank entries of unknown function and 17.5% encode proteins that do not have a GenBank homolog. Using the Gene Ontology hierarchy, we present a first classification of the A. niger proteins encoded by these genes and compare its protein repertoire with other well-studied fungal species. We have established a searchable web-based database that includes the EST and derived contig sequences and their annotation. Details about this project and access to the annotated A. niger database are available. CONCLUSION: This EST collection and its annotation provide a significant resource for fundamental and applied research with A. niger. The gene set identified in this manuscript will be highly useful in the annotation of the genome sequence of A. niger, the genes described in the manuscript, especially those encoding hydrolytic enzymes will provide a valuable source for researchers interested in enzyme properties and applications.

Aspergillus niger↗

PubMed2006

Reduced number and activity of circulating endothelial progenitor cells from patients with hyperhomocysteinemia.

BACKGROUND: Hyperhomocysteinemia (HHcy) contributes to atherosclerosis and coronary artery diseases by inducing endothelial cell injury and dysfunction. Recent studies provided increasing evidence that endothelial progenitor cells (EPCs) participated in ongoing endothelial repair. The changes of EPCs in patients with HHcy have not yet been elucidated. Therefore, we investigated the number and functional activity of EPCs in patients with HHcy. METHODS: Human EPCs were isolated and cultured from patients with HHcy (n = 30) and matched volunteers (n = 30). Circulating EPCs were enumerated as AC133+ KDR+ cells via fluorescence-activated cell sorter analysis. Additionally, EPC were expanded from human blood in vitro and identified by DiI-acLDL uptake and lectin staining by direct fluorescent staining under a laser scanning confocal microscope. EPC migration activities were determined by modified Boyden chamber assay. EPC adhesion assay was performed by replating cells on fibronectin-coated dishes and then counting adherent cells. RESULTS: A significant decrease was observed in circulating EPC (AC133+ KDR+ cells) numbers in patients with HHcy compared with control subjects (63.9 +/- 11.7 cells/mL vs. 91.5 +/- 14.2 cells/mL blood, p <0.01). In addition, the numbers of EPCs also decreased in patients with HHcy after ex vivo cultivation (36.1 +/- 6.5 vs. 51.5 +/- 8.3 EPCs/x200 field, p <0.01). Both circulating EPCs and differentiated EPCs were inversely correlated with total homocysteine levels. In addition, EPCs from patients with HHcy were significantly impaired in their migratory capacity and ability to adhere to fibronectin compared with controls. CONCLUSIONS: The present study demonstrated that EPC numbers and functional capacity were impaired in patients with HHcy.

Aged↗

PubMed2006

Innervation of the trapezius muscle: is cervical contribution important to its function?

OBJECTIVE: To study the effect of the cervical plexus and the accessory nerve to the function of the trapezius muscle. STUDY DESIGN AND SETTING: Eighteen adult male Sprague-Dawley rats were randomly divided into three groups. The neurotomies were performed in the left sides and the right sides served as within-subject controls. In group A, the accessory nerve was transected. The C2-5 were transected in group B, and both of the accessory nerve and C2-5 were cut in group C. The electrophysiologic, myophysiologic, and histologic changes of the muscles were measured. RESULTS: There were significant differences (P < 0.05) between the three groups in the recovery rates of the transverse area of the muscles. The CMAP recorded from the experimental sides in group B were similar to the control sides. The values of the maximum tension of the tetanus contraction between the two sides showed no differences either (P > 0.05). CONCLUSION: The accessory nerve supplies the most important motor input to the trapezius. Motor innervations of the cervical plexus are not very significant.

Accessory Nerve↗

PubMed2006

Analysis of an anti-B lymphocyte stimulator monoclonal antibody B7 and its binding activity to myeloma and lymphoma cell lines.

Although there is convincing evidence of a link between B lymphocyte stimulator (BLyS) and the proliferation and survival of malignant B cells, previous observations about BLyS expression on B lymphoma cells were contradictory. In this study, BLyS expression on human lymphoma and myeloma cell lines was evaluated by Fluorescence-Activated Cell Sorter (FACS). First, specificity of a monoclonal antibody (MAb) against BLyS, was analyzed. The results showed that MAb B7 was immunoglobulin G(3) (IgG(3)) and recognized recombinant human BLyS specifically. In addition, MAb B7 bound to the histiocyte lymphoma cell line U937 in dosage-dependent manner, but not the T lymphoma cell line Jurkat, suggesting that the cellular binding of MAb B7 was specific. Using this MAb, BLyS expression on two multiple myeloma cell lines (XG-7 and SKO-007) and two Burkitt's lymphoma cell lines (Daudi and Raji) was evaluated. MAb B7 did bind to XG- 7 and SKO-007 (66.84% and 79.38% positive cells, respectively). But MAb B7 did not bind Burkitt's lymphoma cell lines, Daudi and Raji (4.09% and 3.02% positive cells, respectively). It will be interesting to further analyze the expression of BLyS on B malignant cells of multiple myeloma and lymphoma patients, and to evaluate the correlation of its expression and patient prognosis.

Antibodies, Monoclonal↗

PubMed2006

Preparation and characterization of a monoclonal antibody against human B lymphocyte stimulator.

B lymphocyte stimulator (BLyS) is a member of the tumor necrosis factor (TNF) family. It is required for B cell development. Deregulation of BLyS was involved in the pathogenesis of B cell-related autoimmune diseases and multiple myeloma. To prepare monoclonal antibodies (MAbs) against BLyS, cDNA encoding soluble BLyS (sBLyS) was first amplified by reverse transcriptase-polymerase chain reaction (RT-PCR) with specific primers, and then inserted into a prokaryotic expression vector pET-30a. Right recombinant plasmid was expressed in Escherichia coli strain BL21(DE3), purified by nickel affinity chromatography. Isolated sBLys was used as an antigen to immunize mice. Splenocytes of one immunized mouse were fused with NS- 1. Hybridomas secreting antibodies against sBLyS were identified by ELISA. One positive clone was selected to produce antibody by injecting the hybridoma into the peritoneal cavity of mice. After collecting ascites, the antibody was purified by protein A affinity chromatography. Western blot and immunoflourescence demonstrated that the antibody could bind recombinant sBLyS and genuine membrane-bound BLyS (mBLyS) on U937. This MAb can be used as a detecting reagent to analyze the serum level of BLyS in patients with autoimmune diseases and the expression profile of mBLyS on multiple myeloma cells.

Animals↗

PubMed2006

Multilayer enhanced gold film over nanostructure surface-enhanced Raman substrates.

We have developed a novel class of gold multilayer, surface-enhanced Raman scattering (SERS) substrates that are capable of enhancing SERS signals by 15.3-fold over conventional gold film over nanostructure (GFON) SERS substrates, making them comparable in sensitivity to optimized silver film over nanostructure (SFON) substrates, while providing the long-term stability obtained from gold. They are fabricated by depositing 10 A thick silver oxide islands on conventional GFON substrates, followed by deposition of a second continuous gold layer. The silver oxide layer acts as a dielectric spacer between the two continuous gold films and produces significantly enhanced SERS signals, as compared to optimized single layer substrates of the same geometry or comparable substrates prepared by deposition of silver islands that are not oxidized. In addition to the enhanced sensitivity of these multilayer substrates, they also exhibit long SERS active shelf-lives (i.e., months), with no measurable degradation in SERS enhancement, and relative standard deviations in SERS enhancement of less than 5.2% across the substrate's surface.

Coated Materials, Biocompatible↗

PubMed2006

[Plasma levels of vWF and NO in patients with metabolic syndrome and their relationship with metabolic disorders].

OBJECTIVE: To measure the plasma levels of von Willebrand factor (vWF) and nitric oxide (NO) in patients with metabolic disorders and to study their relationships with the disease. METHODS: The plasma levels of vWF and NO were determined in patients with metabolic syndrome (MS group, n=36), patients with 1 - 2 metabolic disorders (MD group, n=43) and normal subjects (control group, n=30). RESULT: The plasma vWF level was higher in MS group than that in MD group (P <0.05) and in control group (P <0.001); the vWF level in MD group was higher than that in control group (P <0.05). The NO level was lower in MS group and in MD group than that in control group (both P<0.05), while the difference between MS and MD groups was not statistically significant (P >0.05). Multiple stepwise regression showed that vWF level was correlated with systolic BP (SBP), diastolic BP(DBP) and pulse BP; that NO level was correlated with BMI, SBP and TG. CONCLUSION: Multiple metabolic disorders of metabolic syndrome may injure endothelial cells, and the degree of endothelial cell injury seems to be correlated with the BMI, SBP, DBP, pulse BP and TG.

Blood Pressure↗

PubMed2006

[Cloning and expression of soluble B lymphocyte stimulator].

AIM: To clone and express soluble B lymphocyte stimulator (sBLyS). METHODS: Total RNA was isolated from peripheral blood mononuclear cells, and used to synthesize cDNA by reverse transcription. sBLyS cDNA was amplified by PCR with specific primers and inserted into a prokaryotic expression vector pET-30a. Recombinant plasmid was transformed into E.coli strain BL21(DE3). sBLyS was expressed in E.coli, purified in vitro, and analyzed with peptide mass fingerprinting and Daudi cell proliferation assay. RESULTS: sBLyS cDNA was cloned. Peptide mass fingerprinting of purified BLyS matched with that of BLyS proteins. Purified sBLyS could stimulate Daudi cell proliferation in vitro. CONCLUSION: sBLyS with biological activity was successfully expressed and purified.

Animals↗

PubMed2006

[Surgery of the carotid artery: a retrospective study of 35 consecutive cases].

OBJECTIVE: To retrospectively analyze a single institution's experience with surgery of the carotid artery performed as part of an oncological procedure and emergency hemostasis, with the aim to determine the preoperative methods for evaluation of cerebral circulation, selection of surgical procedures and perioperative complications. METHODS: From January 1999 to December 2004, a total of 35 patients underwent carotid artery surgery including repair of carotid artery in 7 cases, ligation or resection of carotid artery in 17 cases, and reconstruction of carotid artery in 11 cases. All the patients were evaluated for blood flow in the circle of Willis with DSA, DSA plus TBO plus SPECT, and TCD and followed up from 4 months to 4 years. The perioperative complications and surgical outcomes were recorded and analyzed. RESULTS: There were 16 carotid body tumors, 1 malignant carotid body tumor, 17 malignant tumors involving the carotid artery and 1 traumatic arterio-venous fistula. Twenty-seven patients underwent carotid occlusion test, 10 were positive and 17 were negative (tolerable). Of 7 cases with repair of the carotid artery, 1 patient died of uncontrolled bleeding due to rupture of the anastomosis, and the remaining was uneventful. Of 17 cases with ligation or resection of the carotid artery, 4 developed neurologic deficit 2 weeks postoperatively. Three patients with malignant tumors died 1 month, 4 months, and 4 months postoperatively, respectively. One patient with carotid artery body tumor complained of inarticulate speech 4 months after operation; another patient complained of incapability and limited movement of the ipsilateral upper limbs; 5 patients complained of dizziness 4, 6, 12, 24 and 48 months postoperatively. Of 11 patients who underwent carotid reconstruction, no major cerebral complications were noted after operation. One patient died of recurrence, 1 patient with carotid body tumor complained inarticulate speech and incapability of the contralateral limbs, the remaining was uneventful. Color Doppler showed patent vascular graft 1 year postoperatively. CONCLUSIONS: TBO plus SPECT is a reliable method for evaluation of the circle of Willis currently. The short term and long term complications of ligation of carotid artery are high, therefore, resection and revascularization of the carotid artery is advocated for carotid artery tumors when possible.

Adolescent↗

PubMed2006

[The influence of bonding strength of denture soft reline resin by different surface treatments].

PURPOSE: This study evaluated the influence of bonding strength of heat-polymerized denture soft reline resin by 4 different surface treatments bonded to denture base resin. METHODS: Denture base resin (8mm in diameter and 15 mm in length) were fabricated from heat-polymerized acrylic resin (Densply). And heat-polymerized denture soft reline resin disks (Physio liner) were also made (4 mm thick and 10 mm diameter). Two denture base resins were bonded to the denture reline resin disk at the centure on the two sides of the disk. All the specimen were divided into 4 groups (n=10) with 3 different surface treatments: (1) no treatment(control), (2) sandblasted, (3) surface liner application, (4) surface liner application+sandblasted. Bond strength (MPa) was measured by tension bond testing at a 12.7 mm/min speed until the soft reline resin debonded from the base resin. Data were statistically analyzed by SPSS 10.0 software package for ANOVA. RESULTS: The mean bond strengths of group 1, 2, 3, 4 were 3.518, 2.834, 4.077, 3.852MPa respectively. The bonding strength of all the three groups showed significant difference (P<0.0014). The group with surface liner application showed significantly highest bonding strength, while the group with sandblasted showed the lowest bonding strength. CONCLUSIONS: The use of surface liner can significantly improve the bonding strength of heat-polymerized denture soft reline resin to the denture base resin, while the bonding strength decreased after using sandblasting.

Acrylic Resins↗

PubMed2006

[The installation of zygomatic implants and drilling guide].

OBJECTIVE: To discuss the technique of installation of zygomatic implants in severely resorbed edentulous maxillae, and maxillary defect. METHODS: Five patients received 8 zygoma implants and 11 dental implants. On the basis of an axial spiral CT data, anatomical models of natural size were manufactured using CAD/CAM system and before operation preoperative measurements of relevant parameters (length, areas, and volumes) carried out. Theses maxillary and zygomatic measurements obtained were referred for installing zygomatic implants. RESULTS: The ideal direction and position of installation of the 8 zygomatic fixtures were obtained in 5 patients. The anatomical model and surgical plate were used for preoperative planning and intraoperative control of the insertion of zygomatic fixtures. The implants could be positioned precisely as preoperatively planned. The length of the zygomatic implants was between 40 mm and 50 mm. CONCLUSIONS: The use of surgical drilling guides should be encouraged for zygomatic implant placement. 3-D image data and anatomical models improves preoperative planning and facilitates clinical procedure.

Adult↗

PubMed2006

[Qualitative and quantitative determination of the main components of huanglianjiedu decoction by HPLC-UV/MS].

AIM: To establish a comprehensive HPLC analytical method of Huanglianjiedu decoction. METHODS: This study was performed by HPLC-UV/MS to identify the chemical constituents of the whole and individual herbs of the "Huanglianjiedu decoction". Zorbax Extend C18 (150 mm x 4. 6 mm ID, 5 microm) column was used; the mobile phase was composed of acetonitrile (A) and water (B, with 0.5% acetic acid) with gradient elution; the flow rate was 1.0 mL x min(-1) and the column temperature was setup at 25 degrees C. The detection wavelength was 254 nm. RESULTS: The chromatogram of Huanglianjiedu decoction showed 21 main peaks. Peaks 1, 2, 5 and 18 were from Gardenia jasminoides Ellis, Peaks 8, 13, 14, 15, 16, 17, 19 and 21 from Scutellaria baicalensis Georgi. While 10 from Coptis chinensis Franch and 20 from Phellodendron amurense Rupr., Peaks 3, 4, 6, 9, 11 and 12 came from them together. Peak 7 presented in the chromatograms of the herbs except Gardenia jasminoides Ellis. By comparison of the retention time, the on-line UV spectra and MS spectra, 11 peaks were identified as 5 (geniposide), 9 (jatrorrhizine), 10 (coptisine), 11 (palmatine), 12 (berberine), 13 (baicalin), 15 (oroxin A), 17 (wogonoside), 19 (baicalein), 20 (obaculactone), 21 (wogonin), then eight of them were quantified by HPLC-UV. CONCLUSION: The method could represent the characteristics of Huanglianjiedu decoction, and it could be used to evaluate the quality and quantity of Huanglianjiedu decoction. It distinguished between Coptis chinensis Franch and Phellodendron amurense Rupr. by HPLC for the first time.

Berberine↗

PubMed2006

[Three-dimensional finite analysis of the application of attachment for restoration of unilateral maxillary defect].

PURPOSE: To study the stress of the application of attachment for restoration of unilateral maxillary defect. METHODS: Using the 3-D FE model of the unilateral maxillary defect, two different 3-D FE models of the application of attachment framework for restoration of different unilateral maxillary defects (attachment on the mesial side of the central incisor or canine) were designed and established. RESULTS: The area of stress concentration of the two prostheses were on the palatal base near the position of the anterior teeth. The stress was on the posterior teeth of the healthy side. When the attachment was on the mesial side of the central incisor, the stress of the mesial surface of the central incisor was 1.306MPa, and the stress concentration was at the junction of the attachment and the lingual guide plane. When the attachment was on the mesial of the canine, the stress of the mesial surface of the canine was 0.797MPa, and stress concentration was at the corner of the front and bottom of the lingual guide plane. CONCLUSIONS: The application of attachment for restoration of unilateral maxillary defect meets the biomechanical demands without increasing the stress load on the abutment. And further study of the design of the attachment framework should be done.

Dental Abutments↗

PubMed2006

[The construction and analysis of three-dimensional finite element model of human unilateral maxillary defect].

PURPOSE: To built a three-dimensional finite element model of the common unilateral maxillary defect, and to study the stress of the traditional maxillofacial prostheses for unilateral maxillary defect. METHODS: The three-dimensional finite element model of unilateral maxillary defect and maxillofacial obturator prosthesis were constructed by means of spiral CT scanning, digital image transfer, self-developed software MedGraphics, UG engineering design program and ANASYS software. Then 3-D finite element stress analysis was carried out, for the prosthesis. RESULTS: The three-finite element models of the unilateral maxillary defect and maxillofacial obturator prosthesis were established. In the traditional obturator prosthesis, the stress was on the posterior teeth of the healthy side; the area of stress concentration was on the palatal base near the position of the anterior teeth. CONCLUSIONS: The three-dimensional finite element models of the unilateral maxillary defect and maxillofacial obturator prosthesis have good similarity in geometry and biology. The obturator prosthesis is in accorded with the biomechanical demands.

Dental Stress Analysis↗

PubMed2006

[Synthesis of new gene-loaded microbubbles serve as gene delivery vehicle applied in reporter gene transfer into cardiac myocytes].

To improve the stability and gene-carried capability of gene-attached microbubbles, the method for manufacture of albumin microbubbles was modified and new gene-loaded microbubbles were synthesized by incorporated gene-PEI complex into the shell of microbubbles. Agarose gel electrophoresis and bacteria transformation showed that PEI had the ability to provide the protection of plasmid DNA from ultrasonic degradation. The new gene-loaded microbubbles exhibited excellent acoustical and hemorheological properties. Moreover, they could carry more plasmid DNA than gene-attached microbubbles. beta-galactosidase plasmid transfection into cardiac myocytes was performed by using ultrasound targeted destruction of new gene-loaded microbubbles or gene-attached microbubbles. Gene expression in cardiac myocytes was detected by beta-galactosidase in situ staining and quantitive assay. It was shown that beta-galactosidase activity in cardiac myocytes was enhanced 107-fold by ultrasonic destruction of gene-loaded microbubbles compared with naked plasmid transfection and new gene-loaded microbubbles resulted in 6.85-fold increase in beta-galactosidase activity compared with optimal transfection mediated by gene-attached microbubbles. These results suggested that ultrasonic destruction of the gene-loaded microbubbles can enhance the cardiac myocytes exogenous gene transfer efficiency significantly and new gene-loaded microbubbles is an efficient and safe gene delivery vehicle.

Animals↗

PubMed2006

[P21 expression in renal interstitial fibrosis and regulative effect of enalapril].

OBJECTIVE: To investigate the expression of P21 in renal interstitial fibrosis rats and the effect of enalapril on it. METHODS: Sprague Dawley rats were randomly divided into 3 groups: a sham operation group,a unilateral urethral obstruction group, and an enalapril treatment group. The expression of P21 in renal tubular epithelial cells on the process was detected by immunohistochemistry at different time spots (7, 14, 21 d after UUO, sham-surgery or enalapril treatment). The expression of p21 mRNA was detected by reverse transcription-polymerase chain reaction (RT-PCR). RESULTS: Seven days after the surgery, significant differences were found in P21 expression between UUO and SOR renal tubular cells. With degree of interstitial fibrosis aggravating, P21 expression increased. Enalapril can inhibit its expression. CONCLUSION: In the kidney of UUO rats, P21 expression increased and enalapril possessed significant inhibitory effects on the procedure. P21 may participate in the pathogenesis of renal tubule-interstitial fibrosis.

Angiotensin-Converting Enzyme Inhibitors↗

PubMed2006

[Expression of p27 in rat kidney with unilateral ureteral obstruction and the therapeutic effect of enalapril].

OBJECTIVE: To explore the effect of p27 in the renal tubule on the process of renal interstitial fibrosis caused by unilateral ureteral obstruction (UUO) in rats, and to examine the expression changes of p27 after enalapril intervention and to interpret the anti-fibrotic mechanism. METHODS: Ninety rats were randomly divided into the sham-operated group (SOR), UUO group,and UUO+enalapril treatment group [enalapril: 10 mg/(kg.d)]. The rats of each group were respectively sacrificed on 7, 14, 21 days post-operatively. The renal pathological changes were dynamically observed by HE. The expression and dynamic changes of p27 were detected by immunohistochemistry. The level of p27 mRNA were detected by RT-PCR. RESULTS: The expression of p27 in renal tubular epithelial cells and p27 mRNA were strongly positive in the SOR group. With degree of interstitial fibrosis aggravating, the expression of p27 mRNA was gradually reducing. Enalapril could improve the expression of p27 on the 14th and 21st days after the UUO. CONCLUSION: (1) This study supports a causative role of p27 in the formation of fibrosis of renal mesenchyme in rats with UUO. (2) The anti-fibrotic mechanism of enalapril is partly the improvement of p27 expression.

Angiotensin-Converting Enzyme Inhibitors↗

PubMed2006

[Study on antitumor activities of huanglian jiedu decoction].

OBJECTIVE: To study the antitumor activity of Huanglian Jiedu decoction (HLJDT). METHOD: Antitumor activities were tested in mice with experimental tumor H22 in vivo, and the thymus index, spleen index and tumor inhibitory rate were evaluated. The effects on cancer cells from human were investigated in vitro using serum pharmacological approach. Swille, SPC-A-1, SGC-7901 and MCF-7 cancer cells were incubated in culture media containing serum from mice medicated with HLJDT. The inhibitory effects of HLJDT serum were observed by MTT assay. RESULT: HLJDT showed significant antitumor activities on H22 in mice. All of the HLJDT serum in different dosage groups could highly inhibit the proliferation of 4 cancer cell lines from human. CONCLUSION: The HLJDT can significantly inhibit the tumor H22 in mice in a dose-dependent manner, the drug serum has obvious anticancer effects against Swille, SPC-A-1, SGC-7901 and MCF-7.

Animals↗