Association of HbA1c with functional outcome by ischemic stroke subtypes and age.

Objectives: To determine whether high HbA1c levels are related to short-and long-term functional outcomes in patients with ischemic stroke (IS) and whether this association differs according to the IS subtype and the patient's age. Methods: The data of 7,380 IS patients admitted to 16 hospitals or regional stroke centers in South-Korea, between May 2017 and December 2019, were obtained from the Clinical Research Collaboration for Stroke-Korea-National Institute of Health database and retrospectively analyzed. Among these patients, 4,598 were followed-up for one-year. The HbA1c levels were classified into three groups (<5.7, 5.7 to <6.5%, ≥6.5%). Short-and long-term poor functional outcomes were defined using the modified Rankin Scale score of 2 to 6 at three-months and one-year, respectively. IS subtypes were categorized according to the Trial of ORG 10172 in Acute Stroke Treatment (TOAST) classification. Results: There was an association between higher HbA1c (≥6.5%) and poor functional outcomes at three-months in all patients (three-months; OR, 1.299, 95% CI 1.098, 1.535, one-year; OR, 1.181, 95% CI 0.952, 1.465). When grouped by age, the associations after both 3 months and 1 year observed in younger adult group (<65 years), but not in group aged 65 years and older (three-months; <65 years OR, 1.467, 95% CI 1.112, 1.936, ≥65 years OR, 1.220, 95% CI 0.987, 1.507, p for interaction = 0.038, one-year; <65 years OR, 1.622, 95% CI 1.101, 2.388, ≥65 years OR, 1.010, 95% CI 0.778, 1.312, p for interaction = 0.018). Among younger adult group, the higher HbA1c level was related to short-and long-term functional loss in patients with the small vessel occlusion subtype (three-months; OR, 2.337, 95%CI 1.334, 4.095, one-year; OR, 3.004, 95% CI 1.301, 6.938). However, in patients with other TOAST subtypes, a high HbA1c level did not increase the risk of poor outcomes, regardless of the age of onset. Conclusion: High HbA1c levels increase the risk of short-and long-term poor functional outcomes after IS onset. However, this association differs according to stroke subtype and age. Thus, pre-stroke hyperglycemia, reflected by HbA1c, may be a significant predictor for a poor prognosis after ischemic stroke, particular in young- and middle-aged adults.

A systematic review and meta-analysis on the effect of virtual reality-based rehabilitation for people with Parkinson's disease.

BACKGROUND: Virtual reality (VR) is a promising solution for individuals with Parkinson's disease (PD) who experience symptoms that affect their daily activities and independence. Through VR-based rehabilitation, patients can improve their motor skills in a safe and stress-free environment, making it an attractive alternative to traditional in-person rehabilitation during the COVID-19 pandemic. This study aimed to provide the most recent and convincing evidence on the rehabilitative effects of VR technology compared with conventional treatments. METHODS: Two investigators systematically searched Embase, MEDLINE, CINAHL, PEDro, and the Cochrane Library from their inception until May 31, 2022, to identify randomized controlled trials (RCTs) comparing the effectiveness of VR training with that of conventional treatment for patients with PD. Studies were selected based on the patient, intervention, comparator, and outcome criteria and assessed for the risk of bias using the Cochrane tool. Meta-analysis was conducted by pooling mean differences with 95% confidence intervals. RESULTS: A total of 14 RCTs, involving 524 participants, were included in the meta-analysis. The results indicated that VR-based rehabilitation significantly improved balance function, as measured using the Berg balance scale (BBS) and activities-specific balance confidence. However, no statistically significant differences in gait ability, activities of daily living, motor function, and quality of life were observed between the experimental and control groups. Subgroup analysis revealed that combination therapy affected heterogeneity in the BBS analysis. Meta-regression analysis demonstrated a significant positive relationship, indicating that more recent studies have shown greater improvements in balance function. CONCLUSION: This study's findings suggest that VR-based rehabilitation is a promising intervention for improving balance function in patients for PD compared with conventional treatment, and recent research supports its efficacy. However, future research should focus on conducting long-term follow-up studies and developing standardized protocols to comprehensively establish this intervention's potential benefits.

Integrated dataset of the Korean Genome and Epidemiology Study cohort with estimated air pollution data.

Public concern about the adverse health effects of air pollution has grown rapidly in Korea, and there has been increasing demand for research on ways to minimize the health effects of air pollution. Integrating large epidemiological data and air pollution exposure levels can provide a data infrastructure for studying ambient air pollution and its health effects. The Korean Genome and Epidemiology Study (KoGES), a large population-based study, has been used in many epidemiological studies of chronic diseases. Therefore, KoGES cohort data were linked to air pollution data as a national resource for air pollution studies. Air pollution data were produced using community multiscale air quality modeling with additional adjustment of monitoring data, satellite-derived aerosol optical depth, normalized difference vegetation index, and meteorological data to increase the accuracy and spatial resolution. The modeled air pollution data were linked to the KoGES cohort based on participants' geocoded residential addresses in grids of 1 km (particulate matter) or 9 km (gaseous air pollutants and meteorological variables). As the integrated data become available to all researchers, this resource is expected to serve as a useful infrastructure for research on the health effects of air pollution.

A desirable transgenic strategy using GGTA1 endogenous promoter-mediated knock-in for xenotransplantation model.

Pig-to-human organ transplantation is a feasible solution to resolve the shortage of organ donors for patients that wait for transplantation. To overcome immunological rejection, which is the main hurdle in pig-to-human xenotransplantation, various engineered transgenic pigs have been developed. Ablation of xeno-reactive antigens, especially the 1,3-Gal epitope (GalT), which causes hyperacute rejection, and insertion of complement regulatory protein genes, such as hCD46, hCD55, and hCD59, and genes to regulate the coagulation pathway or immune cell-mediated rejection may be required for an ideal xenotransplantation model. However, the technique for stable and efficient expression of multi-transgenes has not yet been settled to develop a suitable xenotransplantation model. To develop a stable and efficient transgenic system, we knocked-in internal ribosome entry sites (IRES)-mediated transgenes into the α 1,3-galactosyltransferase (GGTA1) locus so that expression of these transgenes would be controlled by the GGTA1 endogenous promoter. We constructed an IRES-based polycistronic hCD55/hCD39 knock-in vector to target exon4 of the GGTA1 gene. The hCD55/hCD39 knock-in vector and CRISPR/Cas9 to target exon4 of the GGTA1 gene were co-transfected into white yucatan miniature pig fibroblasts. After transfection, hCD39 expressed cells were sorted by FACS. Targeted colonies were verified using targeting PCR and FACS analysis, and used as donors for somatic cell nuclear transfer. Expression of GalT, hCD55, and hCD39 was analyzed by FACS and western blotting. Human complement-mediated cytotoxicity and human antibody binding assays were conducted on peripheral blood mononuclear cells (PBMCs) and red blood cells (RBCs), and deposition of C3 by incubation with human complement serum and platelet aggregation were analyzed in GGTA1 knock-out (GTKO)/CD55/CD39 pig cells. We obtained six targeted colonies with high efficiency of targeting (42.8% of efficiency). Selected colony and transgenic pigs showed abundant expression of targeted genes (hCD55 and hCD39). Knocked-in transgenes were expressed in various cell types under the control of the GGTA1 endogenous promoter in GTKO/CD55/CD39 pig and IRES was sufficient to express downstream expression of the transgene. Human IgG and IgM binding decreased in GTKO/CD55/CD39 pig and GTKO compared to wild-type pig PBMCs and RBCs. The human complement-mediated cytotoxicity of RBCs and PBMCs decreased in GTKO/CD55/CD39 pig compared to cells from GTKO pig. C3 was also deposited less in GTKO/CD55/CD39 pig cells than wild-type pig cells. The platelet aggregation was delayed by hCD39 expression in GTKO/CD55/CD39 pig. In the current study, knock-in into the GGTA1 locus and GGTA1 endogenous promoter-mediated expression of transgenes are an appropriable strategy for effective and stable expression of multi-transgenes. The IRES-based polycistronic transgene vector system also caused sufficient expression of both hCD55 and hCD39. Furthermore, co-transfection of CRISPR/Cas9 and the knock-in vector not only increased the knock-in efficiency but also induced null for GalT by CRISPR/Cas9-mediated double-stranded break of the target site. As shown in human complement-mediated lysis and human antibody binding to GTKO/CD55/CD39 transgenic pig cells, expression of hCD55 and hCD39 with ablation of GalT prevents an effective immunological reaction in vitro. As a consequence, our technique to produce multi-transgenic pigs could improve the development of a suitable xenotransplantation model, and the GTKO/CD55/CD39 pig developed could prolong the survival of pig-to-primate xenotransplant recipients.

Comparison of islet isolation result and clinical applicability according to GMP-grade collagenase enzyme blend in adult porcine islet isolation and culture.

BACKGROUND: Porcine islet xenotransplantation is a promising treatment for type 1 diabetes as an alternative to human pancreatic islet transplantation and long-term insulin therapy. Several research groups have explored porcine islets as an alternative to the inconsistent and chronic shortage of pancreases from human organ donors. Studies have confirmed successful transplant of porcine islets into non-human primate models of diabetes; however, in most cases, they require more than one adult porcine donor to achieve sufficient viable islet mass for sustained function. The importance of GMP-grade reagents includes the following: specific enzymes utilized in the pancreatic isolation process were identified as a key factor in successful human clinical islet transplantation trials using cadaveric islets. As xenotransplantation clinical research progresses, isolation reagents and digestion enzymes play a key role in the consistency of the product and ultimately the outcome of the islet xenotransplant. In this study, we evaluated several commercially available enzyme blends that have been used for islet isolation. We evaluated their impact on islet isolation yield and subsequent islet function as part of our plan to bring xenotransplantation into clinical xenotransplantation trials. METHODS: Adult porcine islets were isolated from 16 to 17-month-old Yucatan miniature pigs following standard rapid procurement. Pigs weighed on average 48.71 ± 2.85 kg, and the produced pancreases were 39.51 ± 1.80 grams (mean ± SEM). After ductal cannulation, we evaluated both GMP-grade enzymes (Collagenase AF-1 GMP grade and Liberase MTF C/T GMP grade) and compared with standard non-GMP enzyme blend (Collagenase P). Islet quality control assessments including islet yield, islet size (IEQ), membrane integrity (acridine orange/propidium iodide), and functional viability (GSIS) were evaluated in triplicate on day 1 post-islet isolation culture. RESULTS: Islet yield was highest in the group of adult pigs where Collagenase AF-1 GMP grade was utilized. The mean islet yield was 16 586 ± 1391 IEQ/g vs 8302 ± 986 IEQ/g from pancreases isolated using unpurified crude Collagenase P. The mean islet size was higher in Collagenase AF-1 GMP grade with neutral protease than in Collagenase P and Liberase MTF C/T GMP grade. We observed no significant difference between the experimental groups, but in vitro islet function after overnight tissue culture was significantly higher in Collagenase AF-1 GMP grade with neutral protease and Liberase MTF C/T GMP grade than the crude control enzyme group. As expected, the GMP-grade enzyme has significantly lower endotoxin levels than the crude control enzyme group when measured. CONCLUSIONS: This study validates the importance of using specifically blended GMP grade for adult pig islet isolation for xenotransplantation trials and the ability to isolate a sufficient number of viable islets from one adult pig to provide a sufficient number for islets for a clinical islet transplantation. GMP-grade enzymes are highly efficient in increasing islet yield, size, viability, and function at a lower and acceptable endotoxin level. Ongoing research transplants these islets into animal models of diabetes to validate in vivo function. Also, these defined and reproducible techniques using GMP-grade enzymes allow for continuance of our plan to advance to xenotransplantation of isolated pig islets for the treatment of type 1 diabetes.

Facilitation of Bone Healing Processes Based on the Developmental Function of Meox2 in Tooth Loss Lesion.

In the present study, we examined the bone healing capacity of Meox2, a homeobox gene that plays essential roles in the differentiation of a range of developing tissues, and identified its putative function in palatogenesis. We applied the knocking down of Meox2 in human periodontal ligament fibroblasts to examine the osteogenic potential of Meox2. Additionally, we applied in vivo periodontitis induced experiment to reveal the possible application of Meox2 knockdown for 1 and 2 weeks in bone healing processes. We examined the detailed histomorphological changes using Masson's trichrome staining and micro-computed tomography evaluation. Moreover, we observed the localization patterns of various signaling molecules, including α-SMA, CK14, IL-1ß, and MPO to examine the altered bone healing processes. Furthermore, we investigated the process of bone formation using immunohistochemistry of Osteocalcin and Runx2. On the basis of the results, we suggest that the knocking down of Meox2 via the activation of osteoblast and modulation of inflammation would be a plausible answer for bone regeneration as a gene therapy. Additionally, we propose that the purpose-dependent selection and application of developmental regulation genes are important for the functional regeneration of specific tissues and organs, where the pathological condition of tooth loss lesion would be.

Oncostatin M enhances osteogenic differentiation of dental pulp stem cells derived from supernumerary teeth.

Supernumerary tooth (ST) may arise from uncertain developmental abnormalities or underlying genetic causes, and the extraction at the early age is recommended. Dental pulp stem cells (DPSCs) are the valuable resource for the regeneration of tooth and related craniofacial structures. DPSCs isolated from ST (sDPSCs) have not been fully characterized despite the potential in the applications. The objectives of this study are the efficient isolation of sDPSCs and the analysis of the properties as stem cells. sDPSCs were established by hammer-cracking and separation of the intact pulp from ST. sDPSCs in the culture were examined by light microscope and flow cytometer for the morphology and the surface marker expression. sDPSCs exhibited the cellular morphology of typical mesenchymal stem cells and expressed CD44, CD73, CD90, CD105 and CD166, but not CD14, CD34 or CD45. sDPSCs showed the differentiation potential toward osteogenic, chondrogenic and adipogenic lineages. During osteogenic differentiation, the stimulation by Oncostatin M enhanced the differentiation and significantly increased the expression of genes involved in the hard tissue repair, such as BMP2, BMP4, BMP6 and RUNX2. sDPSCs can be effectively derived from ST and displays the characteristics of mesenchymal stem cells in the maintenance and the differentiation. sDPSCs satisfies the quality as DPSCs thus provide the valuable resource to the regenerative therapy.

Presenting characteristics and clinical outcome of patients with COVID-19 in South Korea: A nationwide retrospective observational study.

BACKGROUND: More than 13,000 cases were reported to be infected with COVID-19 by RT-PCR in South Korea. Most studies report clinical characteristics of hospitalized patients with COVID-19; the full spectrum of disease severity has thus not yet been well described. METHODS: Using retrospective observational methods, this study analyzed factors affecting early clinical symptoms, clinical progress, and severity of disease for COVID-19 positive patients released from quarantine to provide information on establishing optimized care for new patients. The medical data of 7803 laboratory-confirmed patients who had been discharged or died by April 30, 2020 were analyzed using multivariate logistic regression analysis. FINDINGS: On admission, 7383 (94•5%) patients were asymptomatic or showed mild illness, and 372 (4•8%) patients were severe illness. Also, 48 (0 0•6%) were hospitalized with critically ill when diagnosed. Most patients with asymptomatic or mild illness on admission remained mild until discharge, 253 (3•4%) progressed to severe illness, and 83 (1•1%) died in hospital. However, the case fatality were 29•8% and 62•5% in severe and critically ill patients, respectively. At admission, 73•0% of hospitalized patients had symptoms; most common were cough (42•5%), sputum (28•8%), and fever (20•1%). Only 35•2% of laboratory confirmed patients admitted to the temporary care facility complained of symptoms. Increasing odds of being critically ill was associated with older age (OR 28•93, 95% CI 13•34-62•75 for age >70y, vs. age <50 y; p<0•0001), being male (OR 2•15, 95% CI1•59-2•89; p<0•0001), fever (OR 2•52, 95% CI 1.84-3•45; p<0•0001), and shortness of breath (OR 7•40, 95% CI 5•37-10•19; p<0•0001). Comorbid illness significantly increased risk of critical illness or death. INTERPRETATION: Most cases were discharged as asymptomatic or recovered from mild illness, and only 9•7% developed severe disease requiring oxygen therapy or more. Case fatality rate was 2•9%, and markedly increased in those over age 50. Risk factors such as age, sex, fever, shortness of breath, and underlying disease can be useful in predicting future clinical severity. Additionally, the number of confirmed asymptomatic COVID-19 patients significantly contribute to continued spread. FUNDING: none.

Identification of Dietary Patterns Associated with Incidence of Hyperglycemia in Middle-Aged and Older Korean Adults.

Little is known about the association between dietary patterns and hyperglycemia incidence among Korean adults. Hence, we aimed to prospectively investigate the major dietary patterns associated with hyperglycemia among middle-aged and older Korean adults. In total, 55,457 adults (18,292 men and 37,165 women) aged 40 to 79 years, who were previously enrolled in the Health Examinee Study of the Korean Genome and Epidemiology Study and had no history of type 2 diabetes mellitus (T2DM) or cancer at baseline, were included. Dietary patterns were identified by a factor analysis based on dietary data, which were assessed at baseline using a validated food-frequency questionnaire. Participants were classified as having hyperglycemia if fasting blood glucose levels were ≥126 mg/dL or physician diagnosed T2DM during follow-up. Multivariable Cox proportional hazard models were used to examine the associations between each dietary pattern and future hyperglycemia risk after adjusting for potential confounders. After a mean follow-up of 4.9 years, 2574 new cases of hyperglycemia were identified. Using a factor analysis, four distinct dietary patterns were identified: "prudent;" "fatty fish, meat, and flour-based food;" "coffee and sweets;" and "whole grain (men)" or "white rice (women)." The "prudent" pattern was inversely associated with hyperglycemia risk only in women (hazard ratio [HR], 0.75; 95% confidence interval [CI], 0.63-0.89; p for trend = 0.0003). Conversely, women in the highest quintile of the "fatty fish, meat, and flour-based food" pattern showed an increased risk of hyperglycemia (HR, 1.22; 95% CI, 1.03-1.44; p for trend = 0.0210) compared with those in the lowest quintile. The "coffee and sweets" and "white rice" patterns were not associated with hyperglycemia risk in women. The dietary patterns observed in men had no associations with hyperglycemia incidence. Our findings suggest that a diet rich in vegetables, mushrooms, seaweeds, fruits, and soy products and low in fatty fish and high-fat meat may potentially play a protective role in T2DM development with sex differences in middle-aged and older Korean adults.

The Korea Biobank Array: Design and Identification of Coding Variants Associated with Blood Biochemical Traits.

We introduce the design and implementation of a new array, the Korea Biobank Array (referred to as KoreanChip), optimized for the Korean population and demonstrate findings from GWAS of blood biochemical traits. KoreanChip comprised >833,000 markers including >247,000 rare-frequency or functional variants estimated from >2,500 sequencing data in Koreans. Of the 833 K markers, 208 K functional markers were directly genotyped. Particularly, >89 K markers were presented in East Asians. KoreanChip achieved higher imputation performance owing to the excellent genomic coverage of 95.38% for common and 73.65% for low-frequency variants. From GWAS (Genome-wide association study) using 6,949 individuals, 28 associations were successfully recapitulated. Moreover, 9 missense variants were newly identified, of which we identified new associations between a common population-specific missense variant, rs671 (p.Glu457Lys) of ALDH2, and two traits including aspartate aminotransferase (P = 5.20 × 10-13) and alanine aminotransferase (P = 4.98 × 10-8). Furthermore, two novel missense variants of GPT with rare frequency in East Asians but extreme rarity in other populations were associated with alanine aminotransferase (rs200088103; p.Arg133Trp, P = 2.02 × 10-9 and rs748547625; p.Arg143Cys, P = 1.41 × 10-6). These variants were successfully replicated in 6,000 individuals (P = 5.30 × 10-8 and P = 1.24 × 10-6). GWAS results suggest the promising utility of KoreanChip with a substantial number of damaging variants to identify new population-specific disease-associated rare/functional variants.

Effect of alanine supplementation during in vitro maturation on oocyte maturation and embryonic development after parthenogenesis and somatic cell nuclear transfer in pigs.

The objective of this study was to examine the effect of alanine treatment during in vitro maturation (IVM) on oocyte maturation and embryonic development in pigs. To this end, we investigated the nuclear maturation, intraoocyte glutathione (GSH) content of IVM oocytes, and embryonic development after parthenogenesis (PA) and somatic cell nuclear transfer (SCNT). In addition, we analyzed the expression of genes associated with apoptosis and embryonic development in IVM oocytes, 4-cell stage embryos, and blastocysts produced via PA and SCNT. To determine the optimal concentration of alanine to promote the maturation and development of PA and SCNT embryos, various concentrations (0, 0.363, 1, 5, and 10 mM) of alanine were added to IVM medium during oocyte maturation. The proportion of metaphase II (MII) oocytes after IVM did not differ according to the concentration of alanine. However, significantly higher intraoocyte GSH content was observed in oocytes treated with 0.363 mM alanine compared with that in untreated oocytes. However, treatment of recipient oocytes with 5 or 10 mM alanine during IVM decreased the GSH content in mature oocytes compared to that in control oocytes. Oocytes matured in the presence of 0.363 mM alanine showed significantly increased rates of cleavage and blastocyst formation after PA and SCNT compared to untreated oocytes. PA and SCNT embryos from the 0.363 mM alanine-treated group of MII oocytes showed significantly higher transcript levels of POU5F1 and FGFR2, which are associated with oocyte quality and embryonic development, than the untreated group. Our results suggest that treatment of pig oocytes with 0.363 mM alanine during IVM improves embryonic developmental competence after PA and SCNT by increasing intraoocyte GSH content and increasing the mRNA expression of POU5F1 and FGFR2.

Dietary carbohydrate quality and quantity in relation to the incidence of type 2 diabetes: A prospective cohort study of middle-aged and older Korean adults.

OBJECTIVES: This study aimed to investigate whether dietary glycemic load (GL), glycemic index (GI), and carbohydrate intake were prospectively associated with incident type 2 diabetes mellitus (T2DM) in a middle-aged and older Korean populations. METHODS: Data from the Korean Genome and Epidemiology Study were used. A total of 7294 Korean adults ages 40 y to 69 y and with no previous diagnosis of T2DM or cancer at baseline were followed for 10 y. Dietary GL, GI, and carbohydrate intake were estimated on the basis of participants' responses to a validated, semiquantitative, food-frequency questionnaire at baseline. T2DM was defined according to the World Health Organization and International Diabetes Federation criteria. RESULTS: During 7.7 y (56 377 person-years) of follow-up time, 1259 participants (17.3%) developed T2DM. Grain and its products (particularly refined and whole grains) were the greatest contributors to dietary GL. In the multivariable Cox models, dietary GL was differentially associated with T2DM risk by sex. Men in the highest quintile demonstrated a higher risk of T2DM incidence than did those with the lowest, energy-adjusted, dietary GL (hazard ratio for fifth vs. first quarter = 1.26; 95% confidence interval, 1.05-1.52; P for trend < 0.05) but no association between dietary GL and the risk of T2DM was observed in women. Similar to the findings from the main models, the effect of dietary GL on T2DM incidence according to body mass index, abdominal obesity, and physical activity levels differed substantially by sex. CONCLUSIONS: High GL diets may increase the risk of the development of T2DM in middle-aged and older Korean men but not in women. Nutrition education and emphasis on self-monitoring of dietary carbohydrate quality and quantity of overall diets is necessary in the middle-aged and older Korean populations.

Role of Notch1 in the arterial specification and angiogenic potential of mouse embryonic stem cell-derived endothelial cells.

BACKGROUND: Endothelial cells have been shown to mediate angiogenesis in ischemic injury sites and contribute to the repair of damaged tissues. However, the treatment of ischemic disease requires a significant number of endothelial cells, which are difficult to isolate from patients. Embryonic stem cells have been considered a potential source of therapeutic cells due to their unlimited self-renewal and pluripotent properties. With regard to vascular development, Notch1 has been established as a key regulator of the specification of arterial endothelial cells. METHODS: Using a doxycycline-induced expression system of the intracellular domain of Notch1, we explored the role of Notch1 in the differentiation of embryonic stem cells to arterial endothelial cells. The therapeutic effect of the arterial endothelial cells was investigated in a murine hindlimb ischemia model. The blood perfusion rate in the ischemic limb was determined by laser Doppler perfusion imaging, and vasculogenesis was quantified using immunocytochemistry. RESULTS: Induced expression of the intracellular domain of Notch1 increased the levels of endothelial markers, such as CD31 and VE-cadherin, in differentiated endothelial cells. Induction of intracellular domain of Notch1 stimulated expression of the arterial-type endothelial cell markers (Nrp1 and Ephrin B2), but not the venous-type endothelial cell markers (Nrp2 and Coup-TFII). In addition, overexpression of intracellular domain of Notch1 resulted in increased expression of CXCR4, a chemokine receptor involved in vascular development. Induction of intracellular domain of Notch1 increased endothelial tube formation and migration of differentiated endothelial cells. Intramuscular administration of Notch1-induced arterial endothelial cells was more effective than administration of the control endothelial cells in restoring the blood flow in an ischemic hindlimb mouse model. Transplantation of Notch1-induced arterial endothelial cells augmented the number of blood vessels and incorporation of endothelial cells into newly formed blood vessels. CONCLUSIONS: These results suggest that Notch1 promotes endothelial maturation and arterial specification during the differentiation of embryonic stem cells to endothelial cells and increases the angiogenic potential of endothelial cells.

Trib2 regulates the pluripotency of embryonic stem cells and enhances reprogramming efficiency.

Embryonic stem (ES) cells are pluripotent cells characterized by self-renewability and differentiation potential. Induced pluripotent stem (iPS) cells are ES cell-equivalent cells derived from somatic cells by the introduction of core reprogramming factors. ES and iPS cells are important sources for understanding basic biology and for generating therapeutic cells for clinical applications. Tribbles homolog 2 (Trib2) functions as a scaffold in signaling pathways. However, the relevance of Trib2 to the pluripotency of ES and iPS cells is unknown. In the present study, we elucidated the importance of Trib2 in maintaining pluripotency in mouse ES cells and in generating iPS cells from somatic cells through the reprogramming process. Trib2 expression decreased as ES cells differentiated, and Trib2 knockdown in ES cells changed their colony morphology while reducing the activity of alkaline phosphatase and the expression of the pluripotency marker genes Oct4, Sox2, Nanog and Klf4. Trib2 directly interacted with Oct4 and elevated Oct4 promoter activity. During the generation of iPS cells, Trib2 knockdown decreased the reprogramming efficiency of mouse embryonic fibroblasts, whereas Trib2 overexpression significantly increased their reprogramming efficiency. In summary, our results suggest that Trib2 is important for maintaining self-renewal in ES cells and for pluripotency induction during the reprogramming process.

Validity of self-reported cancer history in the health examinees (HEXA) study: A comparison of self-report and cancer registry records.

PURPOSE: To assess the validity of the cohort study participants' self-reported cancer history via data linkage to a cancer registry database. METHODS: We included 143,965 participants from the Health Examinees (HEXA) study recruited between 2004 and 2013 who gave informed consent for record linkage to the Korean Central Cancer Registry (KCCR). The sensitivity and the positive predictive value of self-reported histories of cancer were calculated and 95% confidence intervals were estimated. RESULTS: A total of 4,860 participants who had at least one record in the KCCR were included in the calculation of sensitivity. In addition, 3,671 participants who reported a cancer history at enrollment were included in the calculation of positive predictive value. The overall sensitivity of self-reported cancer history was 72.0%. Breast cancer history among women showed the highest sensitivity (81.2%), whereas the lowest sensitivity was observed for liver cancer (53.7%) and cervical cancer (52.1%). The overall positive predictive value was 81.9%. The highest positive predictive value was observed for thyroid cancer (96.1%) and prostate cancer (96.1%), and the lowest was observed for cervical cancer (43.7%). CONCLUSION: The accuracy of self-reported cancer history varied by cancer site and may not be sufficient to ascertain cancer incidence, especially for cervical and bladder cancers.

Small heterodimer partner-interacting leucine zipper protein inhibits adipogenesis by regulating peroxisome proliferator-activated receptor γ activity.

AIMS: Adipocytes play a critical role in energy balance. Growth of fat tissue is achieved via an increase in adipocyte mass and the formation of newly differentiated adipocytes from precursor cells. Understanding the cellular and molecular mechanisms of adipocyte differentiation is crucial for the study of obesity- and fat-related diseases. The present study was designed to study whether small heterodimer partner-interacting leucine zipper protein (SMILE), a novel co-repressor, could regulate differentiation of adipocyte in 3T3-L1 cells. MATERIALS AND METHODS: Treatment of endoplasmic stress inducers, thapsigargin and tunicamycin, inhibited adipocyte differentiation, stimulated Smile mRNA expression, and repressed the expression of adiponectin (Adipoq) in 3T3-L1 pre-adipocyte. Overexpression of SMILE in 3T3-L1 cells decreased the expression of the mRNA encoding Adipoq, a major marker of adipocytes, significantly. Furthermore, knockdown of SMILE recovered the thapsigargin-mediated repression of Adipoq transcription. Co-immunoprecipitation experiments revealed that SMILE interacted physically with PPARγ in 3T3-L1 cells. In addition, chromatin immunoprecipitation experiments revealed that SMILE suppressed the binding affinity of PPARγ for the Adipoq promoter. KEY FINDINGS: We demonstrate that SMILE controls adipocyte differentiation by regulating the transactivity of peroxisome proliferator-activated receptor γ (PPARγ). SIGNIFICANCE: These findings demonstrate that SMILE represses adipocyte differentiation by regulating PPARγ transactivity; hence, SMILE is a potential regulator of PPARγ-related diseases.

Plasma isoflavone concentration is associated with decreased risk of type 2 diabetes in Korean women but not men: results from the Korean Genome and Epidemiology Study.

AIMS/HYPOTHESIS: To examine the association between soybean products and risk of type 2 diabetes, we measured four isoflavone biological markers--genistein, daidzein, glycitein and equol--in a nested case-control study. METHODS: The study population was composed of 693 cases (316 women and 377 men) and 698 matched controls (317 women and 381 men) within the Korean Genome and Epidemiology Study. The concentrations of isoflavone biomarkers were measured using HPLC-MS/MS on plasma samples that were collected at baseline. A stratified analysis was undertaken to examine the association between plasma isoflavone concentrations and risk of type 2 diabetes according to sex and equol production. Logistic regression models were used to compute ORs and 95% CIs adjusted for confounders. RESULTS: In women, compared with the lowest quartile of plasma concentration of genistein, the highest quartile exhibited a significantly decreased risk of diabetes (OR 0.58, 95% CI 0.35, 0.95). When stratified by equol-producing status in women, the OR for diabetes in the highest vs the lowest quartile of genistein concentration was 0.31 (95% CI 0.16, 0.60) in equol producers, but genistein concentration was not associated with risk of diabetes in equol non-producers (p for interaction = 0.013). In men, isoflavone concentrations were not associated with risk of diabetes, regardless of equol-producing status. CONCLUSIONS/INTERPRETATION: High plasma concentrations of genistein were associated with a decreased risk of type 2 diabetes in women. This inverse association was prominent in equol-producing participants. These results suggest a beneficial effect of a high intake of soybean products on risk of type 2 diabetes in women.

SMILE inhibits BMP-2-induced expression of osteocalcin by suppressing the activity of the RUNX2 transcription factor in MC3T3E1 cells.

Small heterodimer partner interacting leucine zipper protein (SMILE) is an orphan nuclear receptor and a member of the bZIP family of proteins. Several recent studies have suggested that SMILE is a novel co-repressor that is involved in nuclear receptor signaling; however, the role of SMILE in osteoblast differentiation has not yet been elucidated. This study demonstrates that SMILE inhibits osteoblast differentiation by regulating the activity of Runt-related transcription factor-2 (RUNX2). Tunicamycin, an inducer of endoplasmic reticulum stress, stimulated SMILE expression. Bone morphogenetic protein-2-induced expression of alkaline phosphatase and osteocalcin, both of which are osteogenic genes, was suppressed by SMILE. The molecular mechanism by which SMILE affects osteocalcin expression was also determined. An immunoprecipitation assay revealed a physical interaction between SMILE and RUNX2 that significantly impaired the RUNX2-dependent activation of the osteocalcin gene. A ChIP assay revealed that SMILE repressed the ability of RUNX2 to bind to the osteocalcin gene promoter. Taken together, these findings demonstrate that SMILE negatively regulates osteocalcin via a direct interaction with RUNX2.

ER stress-inducible ATF3 suppresses BMP2-induced ALP expression and activation in MC3T3-E1 cells.

Endoplasmic reticulum (ER) stress suppresses osteoblast differentiation. Activating transcription factor (ATF) 3, a member of the ATF/cAMP response element-binding protein family of transcription factors, is induced by various stimuli including cytokines, hormones, DNA damage, and ER stress. However, the role of ATF3 in osteoblast differentiation has not been elucidated. Treatment with tunicamycin (TM), an ER stress inducer, increased ATF3 expression in the preosteoblast cell line, MC3T3-E1. Overexpression of ATF3 inhibited bone morphogenetic protein 2-stimulated expression and activation of alkaline phosphatase (ALP), an osteogenic marker. In addition, suppression of ALP expression by TM treatment was rescued by silencing of ATF3 using shRNA. Taken together, these data indicate that ATF3 is a novel negative regulator of osteoblast differentiation by specifically suppressing ALP gene expression in preosteoblasts.

Prospective study of optimal obesity index cutoffs for predicting development of multiple metabolic risk factors: the Korean genome and epidemiology study.

BACKGROUND: In this prospective cohort study, we estimated the risk of developing more than 1 metabolic risk factor, using different obesity indices. In addition, we investigated the relative usefulness of the obesity indices for predicting development of such risk factors and calculated optimal cutoffs for the obesity indices. METHODS: The cohort comprised 10 038 representative residents of a small city and a rural county who were recruited in 2001-2002. Follow-up examinations were conducted every 2 years. Among the 3857 participants without metabolic syndrome at baseline, 1102 new cases occurred during the 6-year follow-up. Receiver operating characteristic (ROC) curves for the obesity indices were plotted to compare the usefulness of the obesity indices. RESULTS: The numbers of new cases of multiple metabolic risk factors among people in the highest quintiles of body mass index (BMI), waist circumference (WC), waist-hip ratio (WHR), and waist-height ratio at the baseline examination were 2 to 3 times those in the lowest quintiles. The area under the ROC curve for WHR was significantly higher than that for BMI. The optimal BMI cutoff was 24 kg/m(2) in men and women, and the optimal WC cutoffs were 80 cm and 78 cm in men and women, respectively. CONCLUSIONS: Both overall obesity and central obesity predicted risk of developing multiple metabolic risk factors, and WHR appeared to be a better discriminator than BMI. To prevent development of metabolic diseases among Koreans, it might be useful to lower the cutoff for abdominal obesity, as defined by WC.