Biomedical subjects

Jie Song

Publications and source records attributed to Jie Song.

26 records · Page 2Linked to original sources

PubMed2004

Platelet-endothelial cell adhesion molecule-1 gene polymorphism and its soluble level are associated with severe coronary artery stenosis in Chinese Singaporean.

OBJECTIVES: Platelet-endothelial cell adhesion molecule-1 (PECAM-1) mediates the transendothelial migration of circulating leukocytes, a characteristic change in vascular inflammation leading to atherosclerotic plaque development. We hypothesized that genetic variation and soluble level of PECAM-1 could be associated with coronary artery disease (CAD). DESIGN AND METHODS: We analyzed two single nucleotide polymorphisms (SNPs) of PECAM-1 gene C+373G (Leu125Val) at exon 3, which encodes the first extracellular (Ig)-like domain that mediates the homophilic binding of PECAM-1, and G+1688A (Ser563Asn) at exon 8 in 144 angiographically documented (> or =70% stenosis) patients with CAD and 150 age- and sex-matched controls in the Chinese population in Singapore, using a polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) strategy. Level of plasma soluble PECAM-1 (sPECAM-1) was measured by ELISA. RESULTS: The Leu125Val polymorphism was associated with CAD (P < 0.01). Also, the level of sPECAM-1 is was found to be elevated in CAD patients (P = 0.005). Moreover, subjects with the homozygous GG genotype of the Leu125Val polymorphism had higher sPECAM-1 levels (P = 0.005). The level of sPECAM-1 was further correlated to soluble platelet selectin (sP-selectin, also measured by ELISA), platelet count, and total white blood cell count (WBC), suggesting that platelets are a major source of sPECAM-1 and platelet activation and inflammation may contribute to PECAM-1 elevations in CAD patients. CONCLUSION: The Leu125Val polymorphism of PECAM-1 and the level of sPECAM-1 are associated with CAD in Chinese in Singapore. The level of sPECAM-1 is also associated with platelet activation and inflammation and correlated to the Leu125Val polymorphism. Our data suggest that PECAM-1 plays an important role in the development of atherosclerosis.

Arteriosclerosis↗

PubMed2004

[A new approach to protein phosphorylation modification analysis for neuron].

OBJECTIVE: To develop a new method for analysis of protein phosphorylation modification in cultured neuron. METHODS: Cultured neurons were pre-incubated in DMEM without sodium phosphate for 15 min to deplete the metabolic pools. Neurons were then labeled with [32P] orthophosphate (2.78 x 10(6) Bq/ml) for 1.5 h and stimulated by either insulin (100 nmol/L), EGF (20 nm/L) or saline for 0, 5, 20, 60, 120 min. Reactions were terminated by freezing neurons in liquid nitrogen prior to the solubilizing of them in a lysis buffer containing 8 mol/L urea, 4% CHAPS, 2% Bio-lyte, pH 3-10, 2 mmol/L TBP. Protein concentrations were determined with Bio-Rad DC Protein Assay kit. The 32P-labled lysates isoelectrically focused on IPG Drystrip pH 3-10 or pH 4-7 Linear gels were subsequently separated in second-dimensional SDS-PAGE. The dried gel was autoradiographed for 5 days at -70 degrees C with an intensifying screen. Alternatively, the separated proteins were visualized by Coomassie Brilliant Blue (CBB) R250 straining. RESULTS: Autoradiography of the 2-DE-separated 32P-laebled neuron lysates revealed around 100 phosphoproteins. This phosphoprotein pattern was stable at 1.5 h after radiolabelling and did not vary significantly for up to 4 h further incubation in the absence of hormone. Most of the major proteins which are phosphorylated in response to insulin or EGF migrated with pH 4.6-6.5 and MW 20000-130000. Insulin and EGF induced similar but not identical patterns of protein phosphoryltion in neurons. Only a few phosphoproteins were abundant enough to be visualized by CBB straining, suggesting that abundance of these phosphoproteins is extremely low. Responses to both isulin and EGF are marked by more increased labeling of the constitutive phosphoproteins, compared with the appearance of new phosphoproteins. CONCLUSION: This approach co-application of 32P-labeled with 2-DE separation and autoradiography has proven to be specific and sensitive in phosphoprotein analysis for neuron. It was valuable in functional proteomic analysis for protein phosphorylation modification during cellular signal transduction.

Animals↗

PubMed2004

Markers of low-grade inflammation and soluble cell adhesion molecules in Chinese patients with coronary artery disease.

BACKGROUND: Inflammation plays an important role in atherosclerosis. Markers of low-grade chronic inflammation, such as C-reactive protein (CRP) and soluble cell adhesion molecules (sCAMs), have been associated with coronary artery disease (CAD). OBJECTIVE: To evaluate the significance of inflammatory markers as novel risk factors for CAD in the Chinese population. METHODS: High-sensitivity CRP (hs-CRP); sCAMs, including vascular cell adhesion molecule-1 (sVCAM-1), intercellular cell adhesion molecule-1 (sICAM-1), P-selectin (sP-selectin) and E-selectin (sE-selectin); and white blood cell (WBC) count were measured in 170 angiographically defined CAD patients (70% or greater stenosis affecting at least one vessel) and 177 healthy control subjects in the Chinese population in Singapore. RESULTS: The levels of hs-CRP, sVCAM-1 and sP-selectin, and the WBC count were higher in CAD patients than in control subjects (P<0.001, P<0.05, P<0.05 and P<0.001, respectively). There were no significant differences in the levels of sICAM-1 and sE-selectin between the two groups. Patients with unstable angina or myocardial infarction had higher levels of hs-CRP, and higher WBC and monocyte counts than those with stable angina or atypical chest pain (all P<0.05). The level of sP-selectin in patients with multivessel disease was higher than in those with single-vessel disease (P<0.05). Overall, the levels of hs-CRP and sCAMs showed a significant correlation with the lipid profile and the WBC count. CONCLUSIONS: The present study suggests that inflammatory markers, including hs-CRP and WBC count, together with sP-selectin and sVCAM-1, could serve as markers of atherogenesis in Chinese patients with CAD, with potential diagnostic and therapeutic implications.

Aged↗

PubMed2003

A new approach to mineralization of biocompatible hydrogel scaffolds: an efficient process toward 3-dimensional bonelike composites.

As a first step toward the design and fabrication of biomimetic bonelike composite materials, we have developed a template-driven nucleation and mineral growth process for the high-affinity integration of hydroxyapatite with a poly(2-hydroxyethyl methacrylate) (pHEMA) hydrogel scaffold. A mineralization technique was developed that exposes carboxylate groups on the surface of cross-linked pHEMA, promoting high-affinity nucleation and growth of calcium phosphate on the surface, along with extensive calcification of the hydrogel interior. Robust surface mineral layers a few microns thick were obtained. The same mineralization technique, when applied to a hydrogel that is less prone to surface hydrolysis, led to distinctly different mineralization patterns, in terms of both the extent of mineralization and the crystallinity of the apatite grown on the hydrogel surface. This template-driven mineralization technique provides an efficient approach toward bonelike composites with high mineral-hydrogel interfacial adhesion strength.

Biocompatible Materials↗

PubMed2002

[Value of three-dimensional digital subtraction angiography in diagnosis and planning endovascular treatment of cerebrovascular diseases].

OBJECTIVE: To evaluate the value of three-dimensional (3D) digital subtraction angiography (DSA) in diagnosis and planning endovascular treatment of cerebrovascular diseases. METHODS: Standard DSA and 3D-DSA were performed in 40 adult patients (aged 21 approximately 74 years) suspected to be with cerebrovascular diseases. The schemes of endovascular treatment were worked out according to the results of 3D-DSA. RESULTS: Positive rate of standard DSA and 3D-DSA were 85.0% and 95.0% respectively in diagnosis of cerebrovascular diseases. 100% occlusion was achieved in 11 patients with intracranial aneurysms and in 7 patients with arteriovenous malformations, and 100% recanalization was achieved in 9 patients with ischemic stroke. Temporary complications were found in 3 of all patients (7.9%). CONCLUSIONS: 3D-DSA is an ideal tool superior to standard DSA in diagnosis of cerebrovascular diseases and has potential value for evaluating endovascular treatment of cerebrovascular diseases.

Adult↗

PubMed2002

Morphological manipulation of bolaamphiphilic polydiacetylene assemblies by controlled lipid doping.

Morphological transformations of bolaamphiphilic polydiacetylene (L-Glu-Bis-3) lipid assemblies from helical ribbons to vesicles and flat sheets through controlled doping are described, and the role of specific lipid dopants in these processes is discussed. Upon doping with cell surface receptor G(M1) ganglioside, fluid vesicular structures start to emerge, coexisting with the micro-crystalline helical ribbons. The vesicle formation is further facilitated and stabilized by the introduction of cholesterol into the system, presumably through surface curvature variation induced by inhomogeneous distribution and dynamic clustering of G(M1) and cholesterol within the doped assemblies. Extended helical ribbons are "truncated" into patches of flat sheets when a sufficient amount of Bis-1, a structurally compatible symmetric bolaamphiphilic diacetylene lipid, is doped. The results reaffirm the important roles of packing geometry and headgroup chirality in the formation of extended helical ribbon structures. The doped assemblies of bolaamphiphiles allow for capture of intermediate structures of morphological transformation using transmission electron microscopy (TEM). A vesicle-to-ribbon transformation mechanism via lateral reorganization within relatively fluid vesicular microstructures has been suggested. Understanding of the doping-induced transformation process provides useful information for the design of advanced materials where the microscopic morphology of material is crucial to its function.

Acetylene↗

PubMed2002

[Genetic polymorphism of 6 short tandem repeat loci in Chinese Korean].

OBJECTIVE: To analyze genetic polymorphism of D16S539 D7S820 D13S317 CSF1PO TPOX and TH01 in Chinese Korean. METHODS: One hundred unrelated individuals were analyzed by PCR amplification fragment length polymorphism analysis. RESULTS: Six alleles and 18 genotypes of D16S539 locus, 7 alleles and 22 genotypes of D7S820 locus, 7 alleles and 23 genotypes of D13S317 locus, 6 alleles and 16 genotypes of CSF1PO locus, 6 alleles and 11 genotypes of TPOX locus, 5 alleles and 12 genotypes of TH01 locus. CONCLUSION: The genotype distribution of all the 6 short tandem repeat(STR) in Chinese Korean met Hardy-Weinberg equilibrium, and have higher heterozygosities. The data obtained can be used in human identity and paternity testing, and in other genetic researches and population investigation.

Alleles↗

PubMedDate not supplied

Accurate classification of homodimeric vs other homooligomeric proteins using a new measure of information discrepancy.

It has been shown that protein primary sequence encodes quaternary structure information. In this present work, function of degree of disagreement (FDOD), a new measure of information discrepancy, is applied to discriminating between homodimers and other homooligomeric proteins from the primary structure. This new approach is based on subsequence distributions of the primary sequences, so the effect of residue order on protein structure is taken into account. When the length of subsequence is 4, the overall accuracy of the 10-fold cross-validation test attains to 82.5%, which is much better than that of the previous method on the same data set. Our tests demonstrate that the residue order along protein sequences plays an important role in the prediction of homooligomers. In addition, our results suggest that FDOD measure is a simple and powerful tool for the prediction of protein multimeric states.

Amino Acid Sequence↗