Relationship between socioeconomic and lifestyle factors and cataracts in Koreans: the Korea National Health and Nutrition Examination Survey 2008-2011.

PURPOSE: Cataracts are the leading cause of visual impairment and blindness, and therefore early identification and modification of the risk factors for cataracts are meaningful. This study aimed to investigate the relationship between socioeconomic status (SES) and lifestyle factors, and age-related cataracts in South Korea. METHODS: This cross-sectional study was based on data collected in the 2008-2011 Korea National Health and Nutrition Examination Survey. A total of 15 866 subjects, aged ≥40 years, were included. SES was defined using household income and education level. Sociodemographic, lifestyle, and other associated factors were assessed by health interviews and examinations. Cataracts were diagnosed via slit-lamp examination using the Lens Opacities Classification System III. RESULTS: The prevalence of any cataract was 38.9% in men and 42.3% in women (P<0.001). In women, the risk of cataracts increased with decreases in household income (P-value for trend=0.016 and 0.041 in any, and cortical cataract, respectively) and education level (P-value for trend=0.009, 0.027, and 0.016 in any, nuclear, and cortical cataract, respectively) after adjusting for confounding factors. Current smoking was correlated with nuclear cataracts in men (OR 1.21; 95% CI: 1.00, 1.46 in age-adjusted analysis) and cataract surgery in women (OR 2.25; 95% CI: 1.00, 5.04 in multivariate-adjusted analysis). CONCLUSIONS: Socioeconomic disparities in cataract prevalence were observed in women; current smoking increased the risk of nuclear cataracts in men and surgery in women. Public health interventions focusing on gender differences are warranted to prevent and treat cataracts.

Sarcopenia and sarcopenic obesity and their association with dyslipidemia in Korean elderly men: the 2008-2010 Korea National Health and Nutrition Examination Survey.

BACKGROUND: Recently, aging has been shown to be associated with sarcopenic obesity (SO), of which decreased muscle mass and increased fat mass are features. Sarcopenia and obesity alone are known to be associated with abnormal lipid metabolism. However, it remains unclear whether SO has greater adverse effects on dyslipidemia than on sarcopenia or obesity alone. AIM: We aimed to investigate the association between SO and dyslipidemia in elderly Koreans. SUBJECTS AND METHODS: This study was based on data collected during the 2008-2010 Korea National Health and Nutrition Examination Survey. We included 1,466 men and 2,017 women aged 65 years and over. Sarcopenia was indicated in participants with height- or weight-adjusted appendicular skeletal muscle that was 1 standard deviation below the sex-specific mean for the young reference group, and obesity was defined as a body mass index ≥ 25 kg/m(2). Dyslipidemia was defined according to the National Cholesterol Education Program-Adult Treatment Panel III. RESULTS: After adjusting for confounding factors, the SO group had a higher risk for dyslipidemia [odds ratio (OR) 2.82 (95 % confidence interval 1.76-4.51)] than the obese group [2.12 (1.11-4.07)] and sarcopenic group [1.46 (1.01-2.11)] (p < 0.001) only in men. Furthermore, the SO group in men had the highest OR for hypercholesterolemia, hypertriglyceridemia, hypo-high-density lipoprotein cholesterolemia, hyper-low-density lipoprotein cholesterolemia, and a high ratio of triglyceride to high-density lipoprotein cholesterol even after further adjustments. CONCLUSIONS: In Korean elderly men, SO was associated with an increased risk for dyslipidemia compared with sarcopenia or obesity alone.

A gene-specific primer extension and liquid bead array system for killer-cell immunoglobulin-like receptor genotyping.

A simple and accurate method for killer-cell immunoglobulin-like receptor (KIR) genotyping is developed using KIR gene-specific primer extension (GSPE) followed by bead array hybridization (GSPE method). After amplification of exons 4, 5, and 9, KIR GSPE and bead array hybridization were performed to verify the presence or absence of 16 KIR subfamilies. GSPE method was validated with natural killer/KIR reference panel I consisting of 48 cell types provided by 13th International Histocompatibility Working Group (IHWG) and genomic DNA from 17 peripheral blood cells, 8 cell lines, and 8 buccal cells. The results of reference panel from GSPE method were 100% concordant with the IHWG reference typing information. All genomic DNAs except reference panel were typed for KIR genes with sequence-specific primer methods and showed 100% identical typing results using this novel system. In addition, GSPE method can obtain results in 8 h from DNA with 10 ng genomic DNA in a 96-well-based assay format.

Distinctive cell cycle regulatory protein profiles by adenovirus delivery of p53 in human papillomavirus-associated cancer cells.

In this study, microarray analyses were performed to determine the time course of gene expression profiles in SiHa cells after infection with an adenovirus-expressing p53 (Adp53). We then investigated the consequences of Adp53 gene transfer on the expression level of six genes associated with cell cycle control and on apoptosis and cell cycle arrest in SiHa cells and compared these results with those from CaSki and HeLa cells. Gene expression profiling of the p53-targeted genes in SiHa cells revealed that p21, p53, and mdm2 protein expression was significantly upregulated at 24 and 48 h. Western blot results revealed that p21 and p53 expression levels had significantly increased after Adp53 infection. Cyclin-dependent kinase 4 levels were decreased 48 h after treatment in SiHa and CaSki cells. Proliferating cell nuclear antigen levels were unchanged after Adp53 infection. Only SiHa cells exhibited significant cell death. Cell cycle arrest at the G1 phase was induced in the SiHa and HeLa cells but was not induced at the G2/M and S phases in the CaSki cells. These data support the notion that the understanding of p53-dependent apoptosis and cell growth arrest could be applicable to advanced strategies in the development of preferential tumor cell-specific delivery.

Reassembly and reconstitution of separate alpha and beta chains of human leukocyte antigen DR4 molecule isolated from Escherichia coli.

The class II major histocompatibility complex molecules play a major role in presentation of exogenous antigenic peptides to the CD4 positive helper T cell. These are heterodimeric cell surface glycoproteins consisting of alpha- and beta-chains. In the present study, we cloned and expressed the alpha- and beta-chain of HLA-DR4 lacking the transmembrane and cytoplasmic domain separately in Escherichia coli using the pET-5a expression vector system. The expressed alpha- and beta-chains were purified in a denaturing condition by an ion exchange chromatography on Q-Sepharose and a gel filtration chromatography on Sephacryl S-200, respectively. The recombinant proteins were refolded and reassembled by removing the denaturing agent and concomitant reoxidation of the disulfide bond. The refolded heterodimeric rDR4 molecule was resolved by 12.5% SDS-PAGE in a nonreducing condition and confirmed by Western blot using polyclonal antibody against DR-alpha and the monoclonal antibody (L243) for the conformationally correct DR molecule. The rDR4 molecules were reconstituted with a 50-fold molar excess biot-HA (307-319), and the bound peptides to the heterodimer complex were determined by a microplate assay coated with L243 antibody using Extravidin-HRP conjugate.

Intrinsic activity and stability of bifunctional human UMP synthase and its two separate catalytic domains, orotate phosphoribosyltransferase and orotidine-5'-phosphate decarboxylase.

Human UMP synthase is a bifunctional protein containing two separate catalytic domains, orotate phosphoribosyltransferase (EC 2.4.2.10) and orotidine-5'-phosphate decarboxylase (EC 4.1.1.23). These studies address the question of why the last two reactions in pyrimidine nucleotide synthesis are catalyzed by a bifunctional enzyme in mammalian cells, but by two separate enzymes in microorganisms. From existing data on subunit associations of the respective enzymes and calculations showing the molar concentration of enzyme to be far lower in mammalian cells than in microorganisms, we hypothesize that the covalent union in UMP synthase stabilizes the domains containing the respective catalytic centers. Evidence supporting this hypothesis comes from studies of stability of enzyme activity in vitro, at physiological concentrations, of UMP synthase, the two isolated catalytic domains prepared by site-directed mutagenesis of UMP synthase, and the yeast ODCase. The two engineered domains have activities very similar to the native UMP synthase, but unlike the bifunctional protein, the domains are quite unstable under conditions promoting the dissociated monomer.

Human uridine monophosphate synthase: baculovirus expression, immunoaffinity column purification and characterization of the acetylated amino terminus.

Human uridine monophosphate (UMP) synthase, a bifunctional protein containing orotate phsophoribosyltransferase (OPRTase, EC 2.4.2.10) and orotidine 5'-monophosphate decarboxylase (ODCase, EC 4.1.1.23) activities, has been overproduced by construction and use of a recombinant baculovirus containing the cDNA for this protein. Expression of the virus in cabbage looper larvae produces a crude larval homogenate having UMP synthase enriched about 180-fold over human placental homogenates and allows larger quantities of this human protein as well as analog proteins to be prepared for structure/function studies. A vastly improved purification procedure using a monoclonal immunoaffinity column was developed. Human UMP synthase purified from larval extracts yielded a product which comigrates in SDS gel electrophoresis with UMP synthase purified from human placenta; pure proteins prepared from these two tissue sources have the same specific activities. We found that OPRTase requires Pi ions in the assay buffers for optimal OPRTase activity; BSA in the assay vessel increases to a lesser degree both OPRTase and ODCase activities. These changes in the assay are essential to observe a parallel enrichment of the two enzyme activities. The baculovirus system was used to express human UMP synthase because it usually yields a product with posttranslational modifications that reflect those of the organism that provided the cDNA. We report data to show that human UMP synthase derived from either human placenta or larval extracts both have a sequence in which the N-terminal methionine has been removed and the formerly penultimate alanine has been acetylated.

Effect of growth temperature on folding of carbamoylphosphate synthetases of Salmonella typhimurium and a cold-sensitive derivative.

The properties of homogeneous preparations of carbamoylphosphate synthetase (CPSase) from wild-type Salmonella typhimurium and a cold-sensitive derivative grown at different growth temperatures were examined. For the cold-sensitive mutant, the affinity for glutamine of the form of CPSase synthesized at 20 degrees C was lower than that of the form of the enzyme synthesized at 37 degrees C, regardless of the assay temperature. Thus, the cold sensitivity of the mutant reflects an effect of temperature on the synthesis of the enzyme rather than the activity of the folded enzyme. The two forms also differed in sensitivities to polyclonal antibodies as well as denaturational enthalpies. The combined results support the hypothesis that carAB mutations conferring cold sensitivity identify amino acid residues that are critical in the folding of CPSase. Quite unexpectedly, certain kinetic properties of cloned parent CPSase were also dependent on the growth temperature, although to a much lesser extent than those of the cold-sensitive mutant. The specific activity of wild-type CPSase synthesized at 15 degrees C was 60% of that synthesized at 37 degrees C. Further, CPSase synthesized at 15 degrees C was less thermostable than the enzyme synthesized at 37 degrees C; the difference in stability (delta G) is estimated to be 4,500 cal mol-1. Thus, variation of temperature within the physiological range for growth influences the folding and consequently the properties of CPSase from wild-type S. typhimurium.