The prevalence of osteoporosis and the rate of bone loss in Korean adults: the Chungju metabolic disease cohort (CMC) study.

Because the rate of bone loss is an important risk factor for fracture, we studied longitudinal changes in bone mineral density (BMD). Although the BMD of the hip decreased over time, spine BMD remained largely stable or increased. Therefore, spine BMD may not be appropriate for assessing BMD change. INTRODUCTION: The rate of age-dependent bone loss has been shown to be an important risk factor for fracture. However, longitudinal rates of BMD loss in Korea have not yet been reported. The objective of this study was to evaluate longitudinal changes in BMD in Korea. METHODS: This cohort study was performed in a population of individuals 40 years of age or older living in the rural area of Chungju City, Korea. A second BMD examination was conducted approximately 4 years after a baseline examination. A total of 3755 of the 6007 subjects completed the follow-up visit, corresponding to a follow-up rate of 62.51%. RESULTS: The age-standardized osteoporosis prevalence was 12.81% in males and 44.35% in females. In males, the average annual BMD loss at the total hip increased from -0.25% per year in their 40s to -1.12% per year in their 80s. In females, the average annual BMD loss at the total hip increased from -0.69% per year in their 40s to -1.51% per year in their 80s. However, the average annual percentage change in spine BMD in females increased from -0.91% per year in their 40s to +1.39% per year in their 80s. CONCLUSIONS: A substantial number of subjects had osteoporosis, even though we standardized the prevalence of osteoporosis. In total hip, the mean BMD was decreased during the follow-up period; in addition, the annual percentage loss increased with age. However, spine BMD remained approximately stable or increased over time and therefore may not be appropriate for assessing BMD change.

Serum preadipocyte factor 1 concentrations and risk of developing diabetes: a nested case-control study.

AIM: To determine whether preadipocyte factor 1 could be a predictive marker for the development of diabetes in people without diabetes at baseline. METHODS: We conducted a population-based, nested case-control study of individuals who progressed to diabetes (n = 43) or prediabetes (n = 345) and control participants matched on age, sex and fasting plasma glucose concentration, who maintained normal glucose tolerance (n = 389) during a 4-year follow-up using data from the Chungju Metabolic disease Cohort Study. Circulating levels of preadipocyte factor 1 were measured using an enzyme-linked immunosorbent assay. RESULTS: Baseline serum preadipocyte factor 1 levels showed a stepwise decrease across the glucose tolerance status groups at follow-up (normal glucose tolerance: 10.02 ± 3.02 ng/ml; prediabetes: 9.48 ± 3.35 ng/ml; diabetes: 8.66 ± 3.29 ng/ml; P for trend, 0.0151). Individuals whose fasting plasma glucose level had increased or whose homeostasis model assessment of ß-cell function had decreased at follow-up showed significantly lower levels of preadipocyte factor 1 compared with their control group counterparts. After adjusting for age, BMI, fasting plasma glucose, serum insulin levels, systolic blood pressure and triglycerides, the incidence of diabetes was nearly threefold higher in the lowest vs. the upper three quartiles of circulating preadipocyte factor 1 (relative risk 2.794; 95% CI 1.188-6.571; P = 0.0185). Notably, these findings were significant in women but not in men. CONCLUSIONS: Levels of circulating preadipocyte factor 1 may be a useful biomarker for identifying women at high risk of developing diabetes.

Postoperative pain and influencing factors among living liver donors.

PURPOSE: In Korea, living donor transplantation is increasing steadily as a life-saving alternative. It is essential to provide living donors the mental and physical care they need throughout their lives including postoperative period. Therefore, this study explored postoperative pain among living liver donors. METHODS: We used a convenience sampling at a university-affiliated hospital from March 1 to August 30, 2009 including 102 subjects. Face-to-face interviews with questionnaires and medical records were used to assess postoperative pain levels, state and trait anxiety as well as satisfaction. Data were analyzed using SPSS 14.0 (SPSS Inc., Chicago, Ill, USA). RESULTS: Average age of donors was 28.9±7.7 years (ranged 16 to 53) with 70.6% male. Most donors (80.4%, n=82) were immediate family members. Ninety-one (89.2%) participants made the decision by themselves. To control postoperative pain, all participants had patient-controlled anesthesia with several types of analgesics as prescribed by physician's preference. The mean values of state anxiety, trait anxiety, and satisfaction in this study were 2.1±1.89, 36.7±7.25 and, 8.9±1.79, respectively. Multivariate analysis showed that trait anxiety and number of analgesics use were significantly associated with postoperative pain. Overall, approximately 29.7% of total variability in postoperative pain could be explained by the nine variables in this model (R2=0.297, F9,102=4.28, (P<.001). There was no multicollinearity checked by tolerance, variation inflation factor, or condition index. CONCLUSION: This study of postoperative pain among living liver donors may contribute to developing the safest, most effective strategy to relieve postoperative pain after living liver donation.

Safety of ultra-rapid intravenous infusion of hepatitis B immunoglobulin in liver transplant recipients.

PURPOSE: To evaluate the safety of institutional protocol for ultra-rapid hepatitis B immunoglobulin (HBIG) infusion (10,000 IU in 30 minutes) for hepatitis B virus prophylaxis in adult liver transplant recipients. METHODS: In this case-controlled study, prospectively recruited liver transplant recipients received ultra-rapid infusions of HBIG (10,000 units in 30 minutes) for 6 months. The historical control group consisted of patients who had received 1-hour HBIG infusions (conventional rapid infusion) for the precedent 6 months. RESULTS: We found that 1472 patients had received 5744 ultra-rapid HBIG infusions, whereas 1343 patients had received 5200 conventional rapid HBIG infusions. Adverse side-effects were observed after 7 (0.13%) and 9 (0.16%) infusions, respectively (P = .763). The number of infusions per month increased significantly, from 878 ± 34 before the introduction of ultra-rapid infusion to 957 ± 29 afterwards (P < .001), an increase of 10.5%. The maximal capacity of HBIG infusions per day in the outpatient clinic increased from 53 for conventional rapid infusion to 65 for ultra-rapid infusion, without expansion of the outpatient facility or equipment. CONCLUSIONS: Nearly all adult liver recipients able to tolerate 1-hour infusions of HBIG can also tolerate ultra-rapid infusions well. Thus, it seems to be reasonable to perform ultra-rapid infusion protocol widely for patient convenience.

Placenta-restricted expression of LTR-derived NOS3.

Domestication events of long terminal repeat (LTR) sequences of the human endogenous retrovirus (HERV) family have been considered to be a new mechanism for the generation of alternative splicing in the human genome. We investigated an LTR10A belonging to the HERV-I family at the human endothelial nitric oxide synthase (NOS3) gene locus. The LTR10A element was located upstream of the original promoter sequences of NOS3. Expression analysis using RT-PCR and reporter gene assays in HCT116 and COS7 cells indicated placenta-specific expression of NOS3 driven by the LTR10A-derived promoter. The placenta-restricted expression was also determined to be associated with hypomethylation of the LTR10A element by methylation analysis using sodium bisulfite DNA sequencing. Furthermore, treatment of brain-derived cell lines with demethylation reagents did not restore expression of the LTR-derived NOS3 gene transcript. Taken together, the integration event of an LTR10A element in the upstream region of NOS3 led to the generation of a placenta-specific alternative transcript governed by cooperative mechanisms of epigenetic control (DNA methylation) and transcriptional regulation (interaction between cis- and trans-acting elements).

Transcriptional regulation of GSDML gene by antisense-oriented HERV-H LTR element.

During the course of hominoid evolution, a new transcript variant of the GSDML (gasdermin-like protein) gene was formed by the integration of the antisense-oriented HERV-H (human endogenous retrovirus) LTR (long terminal repeat) element. To investigate regions that are critical for transcriptional regulation of the GSDML gene, we generated seven deletion mutants from a full-length clone (clone 1/630) that includes the HERV-H LTR sequence and compared their expression levels relative to the full-length parental clone using a transient transfection assay. In the transient transfection assay, deletion of the 5' flanking region (cellular origin) of the HERV-H LTR sequence led to a 4.5-fold increase in expression compared to the full-length clone, while deletion of the U5 region showed a significant decrease in transcriptional activity. Deletion of the 3' flanking region of the LTR sequence (clone 42/451) showed similar transcriptional activity to a clone missing the 5' flanking region of cellular origin (clone 42/630). Taken together, these data indicate that the HERV-H LTR sequence (viral origin) positively regulates transcriptional activity of the GSDML gene and that the 5' flanking region sequence (cellular origin) exerts negative transcriptional regulation.

Long terminal repeats of porcine endogenous retroviruses in Sus scrofa.

Using PCR, sequencing, and bioinformatic approaches with the genomic DNAs of Korean pigs (domestic, wild, and hybrid with Yorkshire), twelve solitary PERV long terminal repeat elements were identified and analyzed. Structure analysis of the LTR elements indicated that they have different repeat sequences in the U3 region. The PERV-A6-KWP1 and -KWP2 elements bear seven and eight 39-bp repeats, respectively. The R region of the PERV LTR elements was highly conserved in pig and mouse genomes, suggesting that they seem to have originated from a common exogenous viral element and then evolved independently throughout the course of mammalian evolution.

Endothelial progenitor cells in pterygium pathogenesis.

PURPOSE: The pathogenesis of pterygium is not well known, and controversy exists about the cell origins and the nature of initial trigger required for its development. We investigated whether endothelial progenitor cells (EPCs) are involved in pathogenesis of pterygium and the mechanism underlying the selective recruitment of EPCs during this process. METHODS: We studied 13 normal controls and 28 pterygium patients (primary (n=15), recurrent (n=13)). Substance-P, vascular endothelial growth factor (VEGF), and stem cell factor (SCF) were measured in plasma and tears using ELISA, and circulating CD34(+) and c-kit(+) mononuclear cells (MNCs) by flow cytometry. Anterior segment fluorescein angiography (FAG) was performed to evaluate hypoxic conditions in the early stage of pterygium. Surgically removed pterygial tissues were analyzed immunohistochemically using the progenitor cell markers, CD34, c-kit, VEGFR-1, and VEGFR-2. RESULTS: Anterior segment FAG findings showed an increase in non-perfusion areas and attenuated vessels in the nasal limbus during early-stage pterygium. Circulating CD34(+) MNCs and c-kit(+) MNCs were increased in pterygium groups compared with normal controls. Systemic and local cytokines including SP, VEGF, and SCF in pterygium groups were also elevated and showed positive correlations with CD34(+) and c-kit(+) MNC numbers. Immunohistochemical analysis of pterygium showed strong progenitor cell marker immunoreactivities. CONCLUSIONS: EPCs might be involved in pterygium development, and ocular hypoxia triggers this neovascularization by recruiting EPCs derived from the bone marrow via the production of systemic and local cytokines.

Transcriptional control of the HERV-H LTR element of the GSDML gene in human tissues and cancer cells.

Long terminal repeats (LTRs) of human endogenous retroviruses (HERVs) have been reported to serve as alternative promoters in functional genes. The GSDML (gasdermin-like protein) gene located on human chromosome 17q21 has been found to be an oncogenomic recombination hotspot. Here, we identified the LTR element of HERV-H with reverse orientation as an alternative promoter of the GSDML gene and analyzed its expression pattern in human tissues and cancer cells. A reporter gene assay of the promoter activity of the LTR on the GSDML gene in human cancer cell lines (HCT-116 and HeLa) and a kidney cell line (Cos7) of African green monkey indicated that the LTR promoter with reverse orientation had stronger promoter activity than forward one. The transcripts of this LTR-derived promoter were widely distributed in various human tissues and cancer cells, whereas the transcripts of the cellular promoter were found only in stomach tissues and some cancer cells (HCT116, MCF7, U937, C-33A, and PC3). These findings suggest that the LTR element on the GSDML gene was integrated into the hominoid lineage and acquired the role of transcriptional regulation of human tissues and cancer cells.

Decision-related factors and attitudes toward donation in living related liver transplantation: ten-year experience.

INTRODUCTION: Living related liver transplantation (LRLT) has been performed since 1994 in Korea; more than 600 donors have contributed to our successful LRLT program for 10 years. Although the decision to donate is difficult and the donors need a formal psychosocial assessment, no system has been available to us for the assessment. This survey was performed as a presurveillance for the development of a psychosocial assessment protocol. METHODS: A survey questionnaire included 31 questions on general and medical characteristics, factors, and processes related to the decision for donation. Donors of partial livers at least 6 months ago during the period from December 1994 to August 2003 and whose address could be confirmed by telephone were enrolled in the study. RESULTS: A questionnaire was sent by mail to 441 contactable donors of whom 209 (47.4%) responded. Male-to-female ratio was 2:1 and mean age was 32.8 years (range: 16 to 60 years). The number of spousal donors was 120 (57.4%) and 164 (78.5%) donors were employed at the time of donation. Protestants, Buddhists, and Catholics were 29.2%, 19.1%, and 14.8%, respectively. Parents were the most common recipients (33.0%), followed by siblings (17.2%), extended family members (17.2%), and children (15.8%); one hundred eighty nine (90.4%) donors had decided by themselves, the major reason for donation in 192 (91.9%) donors was "to save the lives of family members and relatives." The first person who suggested donation was the donor (64.1%), followed by family members (23.9%) or the attending physicians (8.6%). Although 70.8% of donors answered that they were not hesitant to donate at the time of decision, 44.5% were uneasy at the possibility of being unable to sustain a normal life after donation, at their lack of knowledge on organ donation, and about the pain and fear of surgery. Family members and relatives (53.3%), medical personnel (46.7%), and previous donors (35.4%) were the preferable counselors compared to transplantation institutions and clergymen. The large majority (80.8%) of donors would encourage others to donate. CONCLUSIONS: Although the decision to donate was made by the donors themselves in most cases and they appeared firm and determined about their decision, a significant number of donors felt uneasy about possible complications of organ donation and effects on their lives after donation. A precise and formal psychosocial assessment protocol is needed to support and secure their decision before and after donation.

Development of a positive method for male stem cell-mediated gene transfer in mouse and pig.

Classical approaches for producing transgenic livestock require labor-intensive, time-consuming, and expensive methods with low efficiency of transgenic production. A promising approach for producing transgenic animals by using male stem cells was recently reported by Brinster and Zimmermann (1994; Proc Natl Acad Sci 91:11298-11302) and by Brinster and Avarbock (1994: Proc Natl Acad Sci USA 91:11303-11307). However, in order to apply this technique to producing transgenic animals, some difficulties have to be overcome. These include a satisfactory method for short-term in vitro culture for drug selection after transfection with exogenous DNA, and methods for the use of livestock such as pigs. We developed a new method for transferring foreign DNA into male germ cells. Mice and pigs were treated with busulfan, an alkylating agent, to destroy the developing male germ cells, and liposome/bacterial LacZ gene complexes were introduced into each seminiferous tubule by using a microinjection needle. As a control, lipofectin was dissolved in phosphate-buffered saline at a ratio of 1:1, and then injected into seminiferous tubules. In mice, 8.0-14.8% of seminiferous tubule expressed the introduced LacZ gene, and 7-13% of epididymal spermatozoa were confirmed as having foreign DNA by polymerase chain reaction. The liposome-injected testes were all negative for X-gal staining. These results indicate that some spermatozoa were successfully transformed in their early stages by liposome/DNA complexes. In pigs, foreign DNA was also incorporated efficiently into male germ cells, and 15.3-25.1% of the seminiferous tubules containing germ cells expressed the LacZ gene. The data suggest that these techniques can be used as a powerful tool for producing transgenic livestock.

Structure, expression and chromosomal location of the Oct-4 gene.

The map position of Oct-4 on mouse chromosome 17 is between Q and T regions in the Major Histocompatibility Complex (MHC), and it is physically located within 35 kb of a class I gene. Several Oct-4-related genes are present in the murine genome; one of them maps to chromosome 9. The genomic structure and sequence of Oct-4 determined in t-haplotypes reveals five exons, and shows no significant changes in the t12 mutant haplotype making it unlikely that Oct-4 and the t12 early embryonic lethal are the same gene. By in situ hybridization, detectable onset of zygotic Oct-4 expression does not occur until compaction begins at 8-cells, suggesting that there might be other regulatory factors responsible for initiating Oct-4 expression.

tctex-1: a candidate gene family for a mouse t complex sterility locus.

The t complex of the mouse has an important role in male germ cell development and function. Multiple mutations in the t complex interact to alter profoundly the transmission ratio of t complex-bearing sperm or to cause complete sterility or semisterility. We have isolated a multigene family, tctex-1, by screening a testicular cell cDNA library with two reciprocally subtracted testicular cDNA probes. The tctex-1 gene family produces an abundant, virtually germ cell-specific transcript that is 8-fold overexpressed in t homozygotes. The aberrant expression of tctex-1 is solely dependent on the t haplotype genes and occurs only in germ cells. The chromosomal location and pattern of expression of tctex-1 make it a candidate for involvement in male sterility.