A MnlI restriction site polymorphism in the interleukin-10 gene promoter.
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Alleles↗
Biomedical subjects
S Q Ye
Publications and source records attributed to S Q Ye.
An HphI polymorphism in the E-selectin gene is associated with premature coronary artery disease.
An increased expression of E-selectin has been observed in the arterial endothelium interacting with lymphocytes and macrophages in human atherosclerotic lesions. We examined whether a polymorphism in the E-selectin gene, due to a G to T mutation (G98T) in the untranslated region of exon 2, was associated with premature coronary artery disease (CAD). Other lipid and nonlipid risk factors including a Ser to Arg (S128R) substitution in the E-selectin gene were also assessed. In patients with premature CAD (men < or = 45 years old and women < or =55 years old, N = 51) who underwent an elective diagnostic coronary arteriography, the frequency of the mutation was significantly higher than in controls (N = 50, 0.22 vs. 0.10, p = 0.024). After controlling for other CAD risk factors (plasma total cholesterol, triglyceride, LDL-apolipoprotein B. cigarette smoking and the S128R mutation) by multiple logistic analysis, the G98T mutation in the E-selectin gene was still a significant predictor of premature CAD [p = 0.022, odds ratio (95%, CI)= 3.58 (1.20-10.67)].
Alleles↗
[The factors of improving rice transformation efficiency].
The factors influencing the rice transformation frequency have been investigated by using 8 indica and japonica rice cultivars during the transformation procedures, such as induction of calli, selection, and regeneration. The following is the results: The immature embryos were pretreated in 4 degrees C for 4 or 7 days before inoculation, and the regeneration frequency of calli would be increased. High osmotic treatment may increase the possibility of transformation, especially for calli of 6 months or older. The transformation frequency was improved when selection pressure was removed during differentiation period. The V-type selection may be better than the normal selection. There is a difference of differentiation ability among the calli of three periods and it is found that the calli of two or three months are the best for transformation. Proline and DMSO can decrease browning rate of calli.
Dimethyl Sulfoxide↗
miniSAGE: gene expression profiling using serial analysis of gene expression from 1 microg total RNA.
The use of serial analysis of gene expression (SAGE) to determine gene expression profiles is increasing because the technique can provide absolute transcript numbers in a digital format and identify new genes. We developed a miniSAGE technique, which uses only 1 microg total RNA and reduces the amount of the starting material by 250- to 500-fold. Unlike the other modified SAGE methods, the miniSAGE technique does not require the additional PCR amplifications. The additional PCR amplifications potentially introduce bias and compromise the quantitative aspects of the SAGE method. Three key modifications in the miniSAGE technique are: (i) using the phase lock gel (PLG, Eppendorf) to increase the recovery and the purity of DNA material after each phenol extraction step; (ii) reducing the amount of linkers in the ligation, thereby minimizing their interference with SAGE ditag amplification and increasing the SAGE ditag yield; and (iii) employing the mRNA capture kit (Boehringer Mannheim) to allow the first five steps: mRNA isolation, cDNA synthesis, enzyme cleavage of cDNA, binding of the cleaved biotin-cDNA to the streptavidin-magnetic beads, ligating linkers to the bound cDNA, and the release of cDNA tags to occur within one tube to significantly reduce the loss of material between successive steps. Two fibroblast SAGE libraries have been successfully prepared. The preliminary analysis of 3838 tags from one library demonstrated a typical fibroblast gene expression pattern. This miniSAGE technique will permit a broader application of SAGE.
Biopsy↗
Influence of genetic polymorphisms on responsiveness to dietary fat and cholesterol.
Genes influence quantitative variations in plasma lipoprotein concentrations. For example, intake of dietary saturated fat and cholesterol raises the average serum cholesterol concentration, leading to a higher risk of coronary artery disease in populations. However, not all individuals within the population are susceptible: genetic factors appear to render individuals either "dietary responsive" or "dietary nonresponsive." In this review, we focus on current knowledge about the influence of genetic polymorphisms in certain genes on the lipoprotein response to dietary fat and cholesterol. Our preliminary studies in the Dietary Intervention Study in Children suggest a significant dose-response relation between the decrease in LDL cholesterol from baseline to 36 mo of follow-up in both the intervention group (who consumed a low-fat, low-cholesterol diet) and the usual care group (who consumed a regular diet) and the presence of the APOA1*A allele at the M1 site and the + site at the M2 site of the gene encoding apolipoprotein (apo) A-I. The DNA polymorphisms on the genes encoding apo A-IV, apo B, apo C-III, apo E, lipoprotein lipase, cholesteryl ester transfer protein, lecithin:cholesterol acyltransferase (phosphatidylcholine-sterol O:-acyltransferase), and LDL receptor were found by others to be associated with the plasma lipoprotein response to dietary intervention. Possible mechanisms involved in these effects are discussed and certain discrepancies in the literature about some genetic effects on responsiveness are analyzed. An improved understanding of the influence of specific genes on lipoprotein responsiveness to dietary fat and cholesterol may allow us to identify and counsel certain individuals to avoid high-fat diets so that they may reduce their risk of developing hyperlipidemia and coronary artery disease.
Adult↗
A PstI polymorphism detects the mutation of serine128 to arginine in CD 62E gene - a risk factor for coronary artery disease.
The mutation of serine128 to arginine in the CD 62E gene is a risk factor for coronary artery disease (CAD). We designed a new method to detect this mutation based on the observation that it is due to a transversion of nucleotide A561 to C, which abolishes a PstI recognition site. Two alleles, A and C, are easily typed when genomic DNA is amplified by PCR, digested with PstI, and separated on agarose gels. Among 153 people who underwent an elective, diagnostic arteriography in Johns Hopkins Hospital, we found that the C allele accounts for 19.5% in angiographically documented CAD patients (n = 82). It is significantly higher than the 10.6% frequency observed in normal controls (n = 71, p < 0.05). It indicates that the C allele is associated with early-onset CAD. This new method should facilitate the screening of this mutant allele in large populations and contribute to the understanding of the molecular mechanism underlying the association of this mutation with CAD.
Alleles↗
Screening of Epstein-Barr virus early antigen expression inducers from Chinese medicinal herbs and plants.
Ether extracts of 1693 Chinese medicinal herbs and plants from 268 families were studied for the induction of Epstein-Barr viral (EBV) early antigen (EA) expression in the Raji cell line. Fifty-two from 18 families were found to have inducing activity. Twenty-five and seven of them were from Euphorbiaceae and Thymelaeaeeae, respectively. Some of them, such as Croton tiglium, Euphorbia kansui, Daphne genkwa, Wikstroemia chamaedaphne, Wikstroemia indica, Prunus mandshurica Koehne and Achyranthes bidentata are commonly used drugs. The significance of these herbs in the activation of EBV in vivo and their relation to the development of nasopharyngeal carcinoma were discussed.
Antigens, Viral↗
Inhibition of apolipoprotein E degradation in a post-Golgi compartment by a cysteine protease inhibitor.
In our prior studies on lipoprotein stimulation of apolipoprotein E (apoE) secretion in HepG2 cells, it became clear that a proportion of the newly synthesized apoE was degraded intracellularly (Ye, S. Q., Olson, L. M., Reardon, C. A., and Getz, G. S. (1992) J. Biol. Chem. 267, 21961-21966). The present study was designed to determine the nature of the proteases and the intracellular sites involved in newly synthesized apoE degradation. The effect of seven protease inhibitors on total apoE levels was examined. Only N-acetyl-leucyl-leucyl-norleucinal (ALLN), a cysteine protease inhibitor, significantly blocked apoE degradation in HepG2 cells. The amount of total apoE from cells chased with ALLN for 4 h was increased by 1.58 +/- 0.05-fold relative to the controls (n = 11, p < 0.01). ALLN extended the half-life of apoE from 2.61 h to 4.38 h (p < 0.01). This effect occurs in a post-Golgi compartment since in the presence of brefeldin A, ALLN had no effect on intracellular apoE levels. Chloroquine and NH4Cl significantly reduced apoE degradation; however, ALLN plus either of these reagents appear to have an additive effect. The amount of apoE in cells chased in Ca(2+)-free medium was significantly higher than that in cells chased in Ca(2+)-containing medium (1.70 +/- 0.07-fold, n = 6, p < 0.01). ALLN plus Ca(2+)-free medium had no additive effect. ALLN had no significant influence on the degradation of albumin but had a similar effect on transfected apoE in Chinese hamster ovary cells. Overall, these data suggest that apoE may be degraded in a post-Golgi compartment of HepG2 and Chinese hamster ovary cells by lysosomal enzymes and cytosolic Ca(2+)-dependent cysteine proteases. ALLN inhibits the latter.
Albumins↗
Aurothiolates inhibit HIV-1 infectivity by gold(I) ligand exchange with a component of the virion surface.
Aurothioglucose and aurothiomalate have anti-HIV-1 activity in vitro. Antiviral activity requires the formation of a reactive intermediate with a molar equivalent amount of a thiol ligand. This activates gold(I) ligand exchange between the reactive species bis(thiolato)gold(I) and acidic thiol groups exposed on the surface of proteins. Bis(thioglucose)gold(I) (bisAuTG) which is formed by the reaction of molar equivalent amounts of aurothioglucose and 1-thio-beta-D-glucose completely protected MT-4 and CEM cells against HIV-1NL4-3-induced cytopathogenicity. Although bisAuTG is an inhibitor of human immunodeficiency virus-1 (HIV-1) reverse transcriptase in a cell-free assay, its antiviral effect is due to modification of a surface component of the virion. The HIV-1 strain NL4-3 is 200-fold more sensitive to inhibition of infectivity by bisAuTG than are the strains MN, RF, and SF-2. HIV-1NL4-3 has a unique cysteine residue close to the amino terminus of its gp41 envelope glycoprotein (residue 532 of gp160) which we hypothesize is the target of bisAuTG binding. Mutation of that residue alters HIV-1NL4-3 infectivity and dominantly suppresses virus assembly when coexpressed with the wild-type NL4-3 genome. We show that bisAuTG treatment releases gp120 from the surface of cells expressing wild-type HIV-1NL4-3 envelope glycoprotein, but it does not release gp120 if Cys532 is mutationally altered to Ala. Thus, the antiviral effect of bisAuTG on HIV-1NL4-3 is due to an effect on the association of gp120 with gp41.
Amino Acid Sequence↗
Human plasma lipoproteins regulate apolipoprotein E secretion from a post-Golgi compartment.
The molecular regulation of apolipoprotein E (apoE) synthesis and secretion is incompletely understood. In this study, we have examined the effect of human low density lipoprotein (LDL) on apoE mRNA and protein levels in HepG2 and other eukaryotic cells. Exposing HepG2 cells to LDL for times up to 4 h resulted in an increase in 35S-labeled apoE accumulation in the medium by 2.2-fold, relative to serum free controls (n = 10, p < 0.001), with no changes in apoE mRNA levels. Similar observations have been made in JeG-3 cells and Chinese hamster ovary cells stably transfected with human apoE cDNA constructs. These results indicate that the LDL effect operates at a post-transcriptional level. In pulse-chase experiments, the LDL effect on apoE accumulation in the media was observed when it was added only during the chase even in the presence of cycloheximide, indicating that LDL is functioning at a post-translational level. The use of brefeldin A (BFA), an agent that impedes protein transport from the endoplasmic reticulum to the Golgi apparatus, suggests that the LDL effect occurs in a post-Golgi compartment. The addition of protease inhibitors could not duplicate the effects of LDL on the apoE accumulation in the medium. ApoA-I accumulation in the medium of HepG2 cells, but not albumin, was also significantly increased by 1.9-fold (n = 5, p < 0.001).
Albumins↗
Plasminogen polymorphism in swine.
1. Plasminogen polymorphism in swine (Sus scrofa) plasma was demonstrated by immunoblotting. 2. Eleven plasminogen phenotypic patterns, including a null pattern, were detected. 3. The null pattern was associated with extremely low plasma triglyceride and increased unesterified cholesterol levels. 4. Changes in plasminogen polymorphic patterns from the fetal to neonate status were observed after nursing commenced.
Animals↗
Tissue distribution of [3H]cholesteryl linoleyl ether-labeled human Lp(a) in different rat organs.
The sites of tissue uptake of human lipoprotein(a) (Lp(a] were studied in rats using [3H]cholesteryl linoleyl ether [( 3H]CLE) as a marker. Since rat plasma has no cholesteryl ester transfer activity, the amount of label in various tissues should reflect the quantitative uptake of Lp(a). Isolated Lp(a) was labeled with [3H]CLE by incubation overnight of Lp(a), a source of cholesteryl ester transfer activity (1.23 g/ml infranate of human plasma), and [3H]CLE-labeled Intralipid. Following labeling, the homogeneity and integrity of Lp(a) was shown by agarose electrophoresis and immunoblotting. Intact Lp(a) was injected via the tail vein of rats (120-170 g, n = 4 at each time point), and tissues were collected at various times thereafter (4-48 h). The disappearance curve of [3H]CLE-labeled Lp(a) from rat plasma was bimodal and had an initial rapid t1/2 of 1.8 h followed by a slower component, t1/2 = 13.3 h. Tissue uptake at all sampling times was greatest in liver (28.5% at 48 h of total dpm injected), followed by the intestine (9-12%), with less than 3% uptake by spleen. The small intestine was divided into four segments, and while the 3H radioactivity was similar in the proximal segments, a time-related increase in [3H]CLE was seen in its most distal portion. These studies indicate that the tissue sites of degradation in the rat of human Lp(a) are similar to human low-density lipoproteins (LDL); the increase in label in the distal portion of the small intestine with time may represent [3H]CLE excreted through the bile and absorbed by the mucosal cells.
Animals↗
Interactions of low density lipoprotein2 and other apolipoprotein B-containing lipoproteins with lipoprotein(a).
Studies were undertaken to investigate potential interactions among plasma lipoproteins. Techniques used were low density lipoprotein2 (LDL2)-ligand blotting of plasma lipoproteins separated by nondenaturing 2.5-15% gradient gel electrophoresis, ligand binding of plasma lipoproteins by affinity chromatography with either LDL2 or lipoprotein(a) (Lp(a)) as ligands, and agarose lipoprotein electrophoresis. Ligand blotting showed that LDL2 can bind to Lp(a). When apolipoprotein(a) was removed from Lp(a) by reduction and ultracentrifugation, no interaction between LDL2 and reduced Lp(a) was detected by ligand blotting. Ligand binding showed that LDL2-Sepharose 4B columns bound plasma lipoproteins containing apolipoproteins(a), B, and other apolipoproteins. The Lp(a)-Sepharose column bound lipoproteins containing apolipoprotein B and other apolipoproteins. Furthermore, the Lp(a) ligand column bound more lipoprotein lipid than the LDL2 ligand column, with the Lp(a) ligand column having a greater affinity for triglyceride-rich lipoproteins. Lipoprotein electrophoresis of a mixture of LDL2 and Lp(a) demonstrated a single band with a mobility intermediate between that of LDL2 and Lp(a). Chemical modification of the lysine residues of apolipoprotein B (apoB) by either acetylation or acetoacetylation prevented or diminished the interaction of LDL2 with Lp(a), as shown by both agarose electrophoresis and ligand blotting using modified LDL2. Moreover, removal of the acetoacetyl group from the lysine residues of apoB by hydroxylamine reestablished the interaction of LDL2 with Lp(a). On the other hand, blocking of--SH groups of apoB by iodoacetamide failed to show any effect on the interaction between LDL2 and Lp(a). Based on these observations, it was concluded that Lp(a) interacts with LDL2 and other apoB-containing lipoproteins which are enriched in triglyceride; this interaction is due to the presence of apolipoprotein(a) and involves lysine residues of apoB interacting with the plasminogen-like domains (kringle 4) of apolipoprotein(a). Such results suggest that Lp(a) may be involved in triglyceride-rich lipoprotein metabolism, could form transient associations with apoB-containing lipoproteins in the vascular compartment, and alter the intake by the high affinity apoB, E receptor pathway.
Apolipoproteins B↗
[Establishment of a cell line (CNf-A) resistant to 8-azaguanine].
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Azaguanine↗