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Chum salmon (Oncorhynchus keta) is an ecologically and economically important species widely distributed across the North Pacific Ocean. However, the population size of this fishery resource has declined globally. Identifying genetic integrity, diversity and structure, and phylogenetic relationships of wild populations of O. keta over an entire species' range is central for developing its effective conservation and management plans. Nevertheless, chum salmon from the Korean Peninsula, which are comprised of its southwestern range margins, have been overlooked. By using mtDNA control region and 10 microsatellite loci, we here assessed the genetic diversity and structure for 16 populations, including 10 wild and six hatchery populations, encompassing the species entire geographic range in South Korea. The analyses showed that genetic diversity is significantly higher for wild than for hatchery populations. Both marker sets revealed significant genetic differentiation between some local populations. Comparisons of six wild and their respective hatchery populations indicated that allele/haplotype frequencies considerably differ, perhaps due to a strong founder effect and/or homogenizing of hatchery populations for stocking practice. Despite its single admixed gene pool for the Korean chum salmon, some local populations housing their own unique lineages should be accorded with a high priority to safeguard their genetic integrities. The results of our comparative analyses of the Korean population with other North Pacific chum salmons (inhabiting regions of Japan, Russia, and North America) revealed a lower diversity but higher contribution to the overall species‐level genetic diversity, and also its unique genetic integrity. These findings advocate for the evolutionary significance of the Korean population for species‐level conservation. [ABSTRACT FROM AUTHOR]

Decision making is an important brain function. Although little is known about the genetic basis of decision making, it has been suggested that it is mediated by the modulation of neurotransmitter systems. We investigated how the BDNF Val66Met and COMT Val158Met polymorphisms affect emotional decision making using the Iowa Gambling Task (IGT). One hundred sixty-eight healthy Korean college students (93 males, 75 females) with a complete dataset were included in the data analysis. The IGT and genotyping for the polymorphisms of BDNF Val66Met and COMT Val158Met were performed. Both Met/Met and Val/Met of the BDNF Val66Met polymorphism were significantly associated with a lower mean score of blocks 3-5 of the IGT and with less improvement from block 1 to block 3-5 than the Val/Val. However, the BDNF was not significantly associated with the score of block 1, and the COMT Val158Met polymorphism produced no significant effect on IGT performance. No interaction effect was observed between the BDNF and the COMT for the IGT. These findings suggest the BDNF Val66Met may affect the emotional decision making performance., ((c) 2010 Elsevier Ltd. All rights reserved.)

Background: Disgust is a basic emotion that involves feelings of revulsion and withdrawal behavior from dangerous/infectious situations. Very little is known about the genetic basis of disgust sensitivity. The dopamine receptor D4 (DRD4) and catechol-O-methyltransferase (COMT) genes have been implicated in neuroticism-related traits and approach-related temperaments which are supposed to be associated with disgust sensitivity. The present study aimed to investigate the possible relationship between disgust sensitivity and COMT Val158Met and DRD4 variable number of tandem repeats (VNTR) polymorphisms in healthy subjects., Methods: In total, 241 healthy Korean college students were recruited, and the 228 participants with a complete data set (127 males and 101 females) were included in the data analysis. Disgust sensitivity was assessed using the Disgust Scale-Revised (DS-R) and genotyping of COMT Val158Met and DRD4 VNTR polymorphisms was performed., Results: The Val/Val groups of COMT had significantly higher scores than the non-Val/Val group for the Animal-Reminder and the Contamination-Based Disgust scores as well as for total DS-R scores. Additionally, the non-2-repeat allele group of DRD4 had a tendency to a significantly higher disgust sensitivity than the 2-repeat allele group for Contamination-Based Disgust., Conclusions: These findings suggest that disgust sensitivity may be affected by genetic components, such as dopamine-related genes.

Current data concerning the association between family history and the risk for developing stroke have been controversial. There has been very little data on the influence of family history on intracranial atherosclerosis (ICAS), stroke severity, and recovery, especially among Asian populations. We evaluated the association between family history and the risk for stroke and investigated the relationships between family history and ICAS, stroke severity, and short-term stroke outcome in Korean stroke patients. In this case-control study, we recruited 400 patients with acute ischemic stroke, along with the same number of age- and gender-matched control subjects. Assessments of first-degree family history of stroke, myocardial infarction, hypertension and diabetes mellitus were obtained by structured questionnaires, followed by reviews of the clinical and neuro-radiological findings of the stroke patients. A family history of stroke was associated with an increased risk of ischemic stroke (OR, 2.65; 95% CI, 1.75 to 4.01), and the correlation remained significant after multivariate analysis. The odds ratios of paternal, maternal, and sibling history were 2.07, 2.16, and 4.21, respectively. The risk of stroke did not differ significantly with the presence of ICAS, stroke severity, and stroke outcome. Family history of stroke was an independent risk factor for ischemic stroke. A positive sibling history was more strongly correlated with the incidence of stroke than a positive parental history, and this finding may indicate the possible role of environmental factors in a shared household in addition to the genetic factors involved in family medical history.

Worksite health promotion programs focusing on diet and lifestyle modification have been shown to improve health outcomes in workers. The purpose of this study was to investigate whether a 12-week worksite health promotion program shows different response of cardiovascular risk factors in subjects according to apolipoprotein E (Apo E) genotype and obesity level in 141 male Korean industrial workers. We hypothesized that the health changes of a 12-week intervention may not be the same within Apo E genotypes in nonobese and obese subjects. They received 5 face-to-face meetings based on their health profiles. In obese group carrying Apo E3 genotype, body mass index, body fat (%), waist circumference, waist-hip ratio, and systolic blood pressure were decreased, as well as intakes of energy (P = .000) and carbohydrate (P = .005). High-density lipoprotein cholesterol (P = .004) level was improved in individuals with the Apo E2 genotype. These beneficial effects were only observed in individuals with the Apo E2 or Apo E3 genotype. Multiple linear regression revealed that obesity was strongly correlated with waist circumference (P = .002), plasma total cholesterol (P = .037), and changes in dietary cholesterol intake (P = .011) in individuals with the Apo E3 genotype, whereas only changes in dietary fat intake (P = .044) was correlated in those with the Apo E4 genotype. Overall, the results of this study suggest that a health promotion program can be a useful method of improving cardiovascular risk factors and dietary intake in industrial workers with certain genotypes only. Therefore, further research is needed to develop a tailored, long-term worksite health promotion program based on genetic background.

This study was conducted to evaluate the effect of Schisandra nigra, a plant native to Jeju Island, South Korea, on the promotion of hair growth. When rat vibrissa follicles were treated with 85% ethanol (EtOH) extract of S. nigra, the hair-fiber lengths of the vibrissa follicles increased significantly. In addition, after topical application of the EtOH extract of S. nigra onto the back of C57BL/6 mice every other day, anagen progression of the hair shaft was induced. Moreover, the extract increased both the expression of proliferating cell nuclear antigen (PCNA) in the bulb matrix region and the proliferation of immortalized vibrissa dermal papilla cells. In order to determine the mechanism by which S. nigra promotes hair growth, we examined its relationship with the transforming growth factor-beta2 (TGF-beta2) signal pathway, which is known to be a regulator of catagen induction. When the vibrissa follicles in the anagen phase were treated with S. nigra extract for 7 days, the expression of TGF-beta2 in the bulb matrix region was found to be lower than that of the control follicles that were expected to be in the anagen-catagen transition phase. These results suggest that S. nigra extract has the potential to promote hair growth via down regulation of TGF-beta2 and the proliferation of dermal papilla.

The 5-HT1Dbeta receptor gene appears to be particularly interesting in the pathophysiology of obsessive-compulsive disorder (OCD). The 5-HT1Dbeta receptor is a terminal autoreceptor involved in the regulation of serotonin synthesis and release. We performed an association study of the G861C single nucleotide polymorphism (SNP) of the 5-HT1Dbeta receptor in 167 male Korean OCD subjects and in 107 controls. Individuals with the G allele had an increased chance of having OCD (OR 1.49, 95% CI 1.05-2.10). Our findings suggest an association between the G861C SNP of the 5-HT1Dbeta receptor and males with OCD. In the future, other tag SNPs that cover the entire 5-HT1Dbeta gene region as well as additional SNPs that are supposed to have meaningful functions should be investigated in both male and female OCD subjects., (2009 S. Karger AG, Basel.)

Objective: The object of this study is to investigate the prevalence and characteristics of headache in Korean professional women breath-hold divers, including their overuse of analgesics., Background: Headache is a common problem encountered in clinical practice, and undersea divers exhibit unique causes of headache in addition to other common primary headaches. Many scuba divers are known to use various types of drugs to overcome dive-related symptoms or to enhance their underwater performance., Methods: The target population of this study was women divers in the northern district of Jeju Island who were registered in the divers' union. Data were collected using telephone interviews with a structured questionnaire. Headache was diagnosed and classified according to criteria of the International Headache Society., Results: Nine hundred and eleven (80.3%) divers responded to the telephone interview. The prevalence rates of headache were 21.4% for tension-type headache and 9.1% for migraine. One hundred and four divers (11.4%) fulfilled the criteria for chronic daily headache (CDH). Overuse of combination analgesics was reported by 70.7% of divers. Women divers with CDH were significantly older and they complained more of tinnitus and dizziness, and had a greater history of hypertension than divers without headache., Conclusion: The prevalence of CDH is high in Korean professional women breath-hold divers, with many of them being combination-analgesics overusers.

Mental adjustment and coping affect the physical outcome and survival as well as quality of life in cancer patients. The Mini-Mental Adjustment to Cancer (Mini-MAC) scale is a new refined, economical and reliable self-rating instrument measuring cognitive and behavioral responses to cancer. The aim of this study was to evaluate the psychometric properties of the Mini-MAC in Korean cancer patients. A total of 208 cancer patients recruited from the Yonsei Cancer Center were assessed with the Mini-MAC and the Hospital Anxiety and Depression Scale (HADS). Principal component analysis with varimax rotation for the Korean version of Mini-MAC (K-Mini-MAC) confirmed four factors. Three had psychometric properties similar to Helpless-Hopeless (HH), Anxious Preoccupation (AP) and Cognitive Avoidance (CA) of the original Mini-MAC. A novel factor, named Positive Attitude, included items of both Fatalism (FA) and Fighting Spirit (FS) from the original version. The five subscales from the original version (AP, HH, FS, FA and CA) and Positive Attitude had acceptable internal reliabilities in our sample (Cronbach's alpha coefficient 0.50-0.86; correlation coefficient of test-retest 0.68-0.88). For the validity, significant interscale correlation was observed in the original five subscales and Positive Attitude. Each subscale including Positive Attitude was also significantly related to Depression and Anxiety of HADS. As a whole, the K-Mini-MAC was a reliable, valid and acceptable tool for Korean cancer patients. These findings can provide information about the cross-cultural validity of Mini-MAC scale's factor structure. Cultural differences were also discussed.

Background: Stenotrophomonas maltophilia is a significant nosocomial pathogen and is commonly isolated in the hospital environment. We investigated the risk factors for a bloodstream pseudooutbreak of S maltophilia in a general ward., Methods: On November 24 and 25, 2005, 7 patients without evidence of sepsis were reported as positive for blood culture with S maltophilia from blood samples collected on November 21 and 22, 2005. We conducted an epidemiologic investigation and a case-control study of this pseudooutbreak., Results: All 7 S maltophilia showed the same antibiogram and an indistinguishable pattern on pulsed-field gel electrophoresis. The observational study revealed multiple lapses in infection control, including multiple use of a single bottle of saline for dilution of antibiotics. A case-control study showed that one health care worker, who collected blood samples from 6 of 7 patients, was a significant risk factor for the pseudooutbreak of S maltophilia (P < .05)., Conclusion: We suggest that the combination of multiple lapses in infection control and the blood-collecting behavior of a health care worker might be the cause of the pseudooutbreak of S maltophilia.

Although the biological basis of trait anger, anger expression, and forgiveness are not well understood, there has been growing evidence that anger-related dispositions are heritable and associated with genetic polymorphisms. The purpose of the present study was to investigate the possible relationship between anger and forgiveness traits and the dopamine receptor D4 (DRD4) and catechol-O-methyltransferase (COMT) Val158 Met polymorphisms in healthy Korean subjects. Three hundred and thirty-five healthy college students were recruited, and the 308 participants with a complete data set (184 males, 124 females) were included in the data analysis. DNA of the subjects was isolated from whole blood cells, and DRD4 variable number of tandem repeats and COMT Val158 Met polymorphisms were genotyped using polymerase chain reaction. Participants performed the State-Trait Anger Expression Inventory and Trait Forgivingness Scale measuring anger and forgiveness traits. The DRD4 2-repeat (2R) allele group had significantly lower anger in tendency and higher forgiveness traits than the 4R allele group in males. Our results provide evidence that the 2R allele of DRD4 in a Korean sample might have a different function from the 4R allele and a gender-specific role on anger-related traits. The COMT Val158 Met polymorphism had no significant relationship with anger and forgiveness traits. These findings suggest a possible relationship between anger expression styles and forgiveness traits and dopaminergic dysfunction.

A marine bacterium, GW1-1T, capable of degrading benzo[a]pyrene (BaP), was isolated from estuarine sediments of the South Sea (the Korea Strait), Korea, after an enrichment culture maintained for 2 years in a medium supplemented with a mixture of BaP and pyrene. The strain formed yellowish-brown colonies on marine agar 2216. Cells were strictly aerobic, non-motile, Gram-negative rods and produced non-diffusible carotenoid pigments. Optimal growth occurred in the presence of 1 % (w/v) NaCl and at pH 7 and 33-36 degrees C. No growth occurred without supplementation with either CaCl2 or MgCl2, even in the presence of NaCl. Phylogenetic analysis based on the nearly complete sequence of the 16S rRNA gene revealed that the isolate formed a phyletic lineage with the genera Gelidibacter (93.9-94.7 % gene sequence similarity), Subsaximicrobium (93.3 %) and Subsaxibacter (93.9 %). The isolate also showed high sequence similarities to Gaetbulibacter saemankumensis (94.5 %), Algibacter lectus (94.2 %), members of the genus Bizionia (93.6-94.3 %) and Formosa algae (93.2 %), even though it belonged to a different phyletic line. The major respiratory quinones of the isolate were menaquinones MK-5 and MK-6. The DNA G+C content was 51.4 mol%. Dominant fatty acids were i-15 : 0, a-15 : 0, i-15 : 1omega10c and 16 : 1. On the basis of this polyphasic taxonomic evidence, strain GW1-1T is classified as a member of a novel genus and species in the family Flavobacteriaceae, for which the name Yeosuana aromativorans gen. nov., sp. nov. is proposed. The type strain of the type species is GW1-1T (=KCCM 42019T = JCM 12862T).

Hantaan (HTN) virus, the etiologic agent of clinically severe hemorrhagic fever with renal syndrome (HFRS), was first isolated in 1976 from lung tissue of a striped-field mouse (Apodemus agrarius) captured in Songnae-ri, Gyeonggi Province, Republic of Korea. Found primarily in mountainous areas, the Korean field mouse (A. peninsulae) is the second-most dominant field rodent species found throughout Korea. A new hantavirus, designated Soochong (SOO), was isolated in Vero E6 cells from four A. peninsulae captured in August 1997 at Mt. Gyebang in Hongcheon-gun, Mt. Gachil, Inje-gun, Gangwon Province, and in September 1998 at Mt. Deogyu, Muju-gun, Jeollabuk Province. The entire S, M, and L genomic segments of SOO virus, amplified by RT-PCR from lung tissues of seropositive A. peninsulae and from virus-infected Vero E6 cells, diverged from HTN virus (strain 76-118) by 15.6%, 22.8%, and 21.7% at the nucleotide level and 3.5%, 9.5%, and 4.6% at the amino acid level, respectively. Phylogenetic analyses of the nucleotide and deduced amino acid sequences, using the maximum parsimony and neighbor-joining methods, indicated that SOO virus was distinct from A. agrarius-borne HTN virus. SOO virus shared a common ancestry with Amur virus from Far East Russia, as well as with H5 and B78 hantaviruses, previously isolated from HFRS patients in China. Cross-focus-reduction neutralizating antibody tests showed that SOO virus, which is the first hantavirus isolated in cell culture from A. peninsulae, could be classified as a new hantavirus serotype., (Copyright 2005 Wiley-Liss, Inc.)

Background: Few studies have investigated the association between age at smoking initiation and Fagerström test for nicotine dependence (FTND) in adulthood. The goal of this study was to develop the Korean version of FTND (FTND-K) and to examine the relationship between age at smoking initiation and nicotine dependence., Methods: This investigation used data from 268 current smokers who visited the Center for Cancer Prevention and Early Detection in the National Cancer Center, Korea. The internal consistency of the FTND-K was assessed by Cronbach's coefficient alpha. Pearson's correlation coefficients were used to assess the relationships between the FTND-K sum scores and urinary cotinine levels. One-way analysis of variance (ANOVA) and t-tests were used to assess differences in the FTND-K sum score between groups. Factor associated with nicotine dependence were identified through stepwise multiple logistic regression analysis., Results: The standardized Cronbach's alpha of FTND-K was 0.72. A significant positive correlation was seen between the FTND-K sum score and urinary cotinine level (correlation coefficient = 0.49, P < 0.05). Age at smoking initiation had a significant association with the FTND-K sum score in univariate analysis. In multivariate analysis, nicotine dependence was higher in smokers that started smoking cigarettes at 19 years or earlier than in those that started at 25 years or later (OR = 11.25, 95% CIs, 1.46-97.10)., Conclusions: The FTND-K is a valid assessment tool of nicotine dependence with acceptable levels of internal consistency and close correlation to urinary cotinine level. The finding that those who initiate smoking at an early age tend to be more nicotine dependent underscores and reinforces the public health significance of delaying smoking onset.