To investigate the perceptions and attitudes of dental hygienists toward radiation safety management in Korea. A total of 800 dental hygienists were randomly selected for an anonymous survey, and 203 of them participated. The questionnaire items included the following: sex, career period, type of installed radiographic equipment, recognition of the diagnostic reference level (DRL), participation in radiation safety education, and attitudes toward radiation protection for both patients and dental hygienists. The participants were divided into two groups according to their years of experience (< 10 years versus ≥ 10 years). The difference between the groups was investigated according to frequency distribution. Fisher’s exact test or Pearson’s chi-square (χ2 ) test was used as appropriate. A regression analysis was performed to investigate the impact of wearing a thyroid collar for personnel protection during patient radiation exposure. The types of installed radiographic equipment included panoramic radiography (96.1%), cephalometric radiography (76.9%), intraoral radiography (72.9%), and cone-beam computed tomography (69.5%). Significant differences were observed in the learning pathway for the DRL (Fisher’s exact test, p < 0.05), satisfaction with radiation safety education (Pearson’s χ2 test = 5.3975, Pr = 0.02), and use of personnel radiation monitoring systems (Pearson’s χ 2 test = 18.1233, Pr = 0.000) between the groups. Significant differences were also observed in personnel protection using a thyroid collar and patient protection during panoramic radiography (odds ratio = 14.2). Dental hygienists with more than 10 years of experience were more satisfied with radiation safety education and more interested in radiation monitoring. Considering career experience, customized, continuous, and effective radiation safety management education should be provided.

Background: and PurposeMild cognitive impairment (MCI) is a condition with diverse clinical outcomes and subgroups. Here we investigated the topographic distribution of tau in vivo using the positron emission tomography (PET) tracer [18F]THK5351 in MCI subgroups. Methods: This study included 96 participants comprising 38 with amnestic MCI (aMCI), 21 with nonamnestic MCI (naMCI), and 37 with normal cognition (NC) who underwent 3.0-T MRI, [18F]THK5351 PET, and detailed neuropsychological tests. [18F]flutemetamol PET was also performed in 62 participants. The aMCI patients were further divided into three groups: 1) verbal-aMCI, only verbal memory impairment; 2) visual-aMCI, only visual memory impairment; and 3) both-aMCI, both visual and verbal memory impairment. Voxel-wise statistical analysis and region-of-interest -based analyses were performed to evaluate the retention of [18F]THK5351 in the MCI subgroups. Subgroup analysis of amyloid-positive and -negative MCI patients was also performed. Correlations between [18F]THK5351 retention and different neuropsychological tests were evaluated using statistical parametric mapping analyses. Results: [18F]THK5351 retention in the lateral temporal, mesial temporal, parietal, frontal, posterior cingulate cortices and precuneus was significantly greater in aMCI patients than in NC subjects, whereas it did not differ significantly between naMCI and NC participants. [18F] THK5351 retention was greater in the both-aMCI group than in the verbal-aMCI and visualaMCI groups, and greater in amyloid-positive than amyloid-negative MCI patients. The cognitive function scores were significantly correlated with cortical [18F]THK5351 retention. Conclusions [18F]THK5351 PET might be useful for identifying distinct topographic patterns of [18F]THK5351 retention in subgroups of MCI patients who are at greater risk of the progression to Alzheimer's dementia.

OBJECTIVE: Restless legs syndrome (RLS) is a highly heritable and common neurological sensorimotor disease disturbing sleep. The objective of study was to investigate significant gene for RLS by performing GWA and replication study in a Korean population. METHODS: We performed a GWA study for RLS symptom group (n=325) and non-RLS group (n=2,603) from the Korea Genome Epidemiology Study. We subsequently performed a replication study in RLS and normal controls (227 RLS and 229 controls) to confirm the present GWA study findings as well as previous GWA study results. RESULTS: In the initial GWA study of RLS, we observed an association of rs11645604 (OR=1.531, p=1.18×10−6) in MPHOSPH6 on chromosome 16q23.3, rs1918752 (OR=0.6582, p=1.93×10−6) and rs9390170 (OR=0.6778, p=7.67×10−6) in UTRN on chromosome 6q24. From the replication samples, we found rs9390170 in UTRN (p=0.036) and rs3923809 and rs9296249 in BTBD9 (p=0.045, p=0.046, respectively) were significantly associated with RLS. Moreover, we found the haplotype polymorphisms of rs9357271, rs3923809, and rs9296249 (overall p=5.69×10−18) in BTBD9 was associated with RLS. CONCLUSION: From our sequential GWA and replication study, we could hypothesize rs9390170 polymorphism in UTRN is a novel genetic marker for susceptibility to RLS. Regarding with utrophin, which is encoded by UTRN, is preferentially expressed in the neuromuscular synapse and myotendinous junctions, we speculate that utrophin is involved in RLS, particularly related to the neuromuscular aspects.
Epidemiology ; Genetic Markers ; Genome ; Genome-Wide Association Study* ; Haplotypes ; Korea ; Restless Legs Syndrome* ; Synapses ; Utrophin

OBJECTIVES: There are emerging evidences suggest that the development of tardive dyskinesia (TD) is related to the oxidative stress, excitotoxicity, and immune activation. The purpose of this study is to investigate whether single-nucleotide polymorphisms (SNPs) of tumor necrosis factor (TNF)-alpha genes are associated with the susceptibility of TD and schizophrenia. METHODS: We investigated two hundred and eighty Korean schizophrenic patients. The schizophrenic participants consisted of patients with (n=105) and without (n=175) TD who were matched for antipsychotic drug exposure and other relevant variables. The TNF-alpha gene -308G/A SNPs were analyzed by polymerase chain reaction (PCR)-based methods. RESULTS: The frequencies of genotype (chi2=0.33, p=0.848) of the TNF-alpha gene -308 G/A SNP did not differ significantly between schizophrenic patients with and without TD. The difference of allele frequencies (chi2=0.28, p=0.594) of the TNF-alpha gene between the schizophrenic patients with and without TD were not significant. CONCLUSION: These results suggest that the TNF-alpha gene -308 G/A SNPs are not associated with TD and schizophrenia in a Korean population. Further association studies of TD with other candidate genes for cytokines would help us understand the pathophysiological mechanisms of TD.
Cytokines ; Gene Frequency ; Genotype ; Humans ; Movement Disorders ; Oxidative Stress ; Polymerase Chain Reaction ; Polymorphism, Genetic ; Polymorphism, Single Nucleotide ; Schizophrenia ; Tumor Necrosis Factor-alpha

OBJECTIVES: Several evidence has been suggested that the circadian gene variants contribute to the pathogenesis of seasonal affective disorder. In this study, we aimed to investigate the polymorphism in RORA (Retinoid-related orphan receptor A) gene in relation to seasonal variations among healthy young adults in Seoul, Korea. METHODS: A total of 507 young healthy adult subjects were recruited by advertisement. Seasonal variations were assessed by the Seasonality Pattern Assessment Questionnaire (SPAQ). Single-nucleotide polymorphism in the RORA rs11071547 gene was genotyped by PCR in 507 individuals. Considering summer type as confounding factor, we conducted analysis 478 subjects except 29 subjects of summer type. The Chi-square test was conducted to compare differences between groups of seasonals and non-seasonals. Association between genotypes and Global Seasonality Score (GSS) were tested using ANCOVA (Analysis of covariance). RESULTS: In this sample, the prevalence of SAD was 12.1% (winter type 9.3%, summer type 2.8%). There is no significant difference in genotyping distribution of RORA rs11071547 between groups of seasonals and non-seasonals. Global seasonality score (GSS) and scores of all subscales except body weight and appetite were not significantly different between the group with C allele homozygote and the group with T allele homozygote and heterozygote (p-value 0.138). Scores of body weight and appetite were significantly higher in group with C allele homozygotes. CONCLUSION: These results suggest that RORA gene polymorphism play a role in seasonal variations in appetite and body weight and is associated with susceptibility to seasonal affective disorder in some degree in the population studied.
Adult ; Alleles ; Appetite ; Body Weight ; Child ; Child, Orphaned ; Genotype ; Heterozygote ; Homozygote ; Humans ; Korea ; Polymerase Chain Reaction ; Prevalence ; Surveys and Questionnaires ; Seasonal Affective Disorder ; Seasons* ; Seoul ; Young Adult

OBJECTIVES: The previous studies have suggested genetic vulnerability to restless legs syndrome (RLS) development. The occurrence of antipsychotic-related RLS could also be attributable to differences in genetic susceptibility. This study aimed to investigate whether Retinoid-related orphan receptor A (RORA) gene polymorphism is associated with antipsychotic-related RLS in schizophrenia. METHODS: We assessed symptoms of antipsychotic-induced RLS in 190 Korean schizophrenic patients and divided the subjects into two groups according to the International Restless Legs Syndrome Study Group diagnostic criteria : 1) subjects that met all of the criteria (n=44) and 2) the remaining subjects who were not considered to be RLS patients (n=146). Single-nucleotide polymorphism in the RORA gene was genotyped by PCR in 190 individuals. The chi2-test was conducted to compare differences between two groups. RESULTS: The frequencies of genotype (chi2=0.066, p=0.968) of the RORA gene (rs11071547) did not differ significantly between schizophrenic patients with and without RLS. The difference of allele frequencies (chi2=0.008, p=0.927) of the RORA gene (rs 11071547) between the schizophrenic patients with and without RLS were not significant. CONCLUSION: These results suggest that RORA gene polymorphism does not play a major role in susceptibility to antipsychotic-related RLS in schizophrenia.
Child ; Child, Orphaned ; Circadian Rhythm ; Gene Frequency ; Genetic Predisposition to Disease ; Genotype ; Humans ; Polymerase Chain Reaction ; Polymorphism, Genetic ; Restless Legs Syndrome* ; Schizophrenia*

Tardive dyskinesia (TD) is a hyperkinetic movement disorder associated with the prolonged use of antipsychotic drugs. Since prostate apoptosis response 4 (Par-4) is a key ligand of the dopamine D2 receptor, the Par-4 gene (PAWR) is a good candidate gene to study in the context of TD susceptibility. We examined the association between PAWR gene polymorphisms and TD. Three single nucleotide polymorphisms of PAWR were selected for the analysis: rs7979987, rs4842318, and rs17005769. Two hundred and eighty unrelated Korean schizophrenic patients participated in this study (105 TD and 175 non-TD patients). Genotype/allele-wise and haplotype-wise analyses were performed. There were no significant differences in genotype and allele frequencies between the two groups. Haplotype analysis also did not reveal a difference between the two groups. Within the limitations imposed by the size of the clinical sample, these findings suggest that PAWR gene variants do not significantly contribute to an increased risk of TD.
Antipsychotic Agents ; Apoptosis ; Gene Frequency ; Genotype ; Haplotypes ; Humans ; Hyperkinesis ; Movement Disorders ; Polymorphism, Single Nucleotide ; Prostate ; Receptors, Dopamine D2 ; Schizophrenia

Duloxetine is a balanced serotonin-norepinephrine reuptake inhibitor. Duloxetine-induced liver injury in patients with preexisting liver disease or chronic alcohol use is known. However, we have found that duloxetine can also induce liver injury in cases without those risk factors. We recommend that clinicians should monitor liver function carefully following duloxetine treatment.
Depressive Disorder, Major ; Humans ; Liver ; Liver Diseases ; Organothiophosphorus Compounds ; Risk Factors ; Thiophenes ; Duloxetine Hydrochloride

OBJECTIVE: Diurnal preference is an attribute reflecting whether people are alert and preferring to be active either early or late in the day. It also referred to as chronotype or morningness-eveningness trait. The PER3 genes have been known to influence diurnal preference. In this study, we have investigated the associations between the PER3 gene polymorphisms and diurnal preference in a healthy young population, controlling for the social and environmental confounding factors. METHODS: The participants in this experiment included 299 unrelated medical college students (M=191, F=108), with a mean age of 22.9 years. Diurnal preference was measured by a single administration of the 13-item Composite Scale for Morningness (CSM). Genotyping of the PER3 VNTR (rs57875989) was performed using polymerase chain reaction. A two-tailed alpha of 0.05 was chosen. RESULTS: The mean+/-SD score on the CSM scale for all subjects was 31.90+/-6.39. There was no significant difference in total CSM score between gender groups, although females showed a trend towards higher morningness score. Although PER3 5R/5R showed the tendency towards high CSM scores, there were no significant differences on CSM scores among genotypes and allele status of PER3 VNTR (rs57875989). CONCLUSIONS: We could not confirm that the PER3 VNTR is associated with diurnal preference in a Korean healthy young population. The future studies need to investigate the association between diurnal preference and other polymorphisms of PER3 gene in larger sample of Korean young healthy population.
Alleles ; Female ; Genotype ; Humans ; Polymerase Chain Reaction

PURPOSE: Although acute renal failure (ARF) commonly develops in patients with severe acute pancreatitis (SAP), the impact of ARF on disease severity is rarely reported in Korea. This study was performed to compare the clinical findings, morbidity and mortality between SAP patients with and without ARF. METHODS: We retrospectively evaluated the medical records of 102 patients with SAP between january 2001 and June 2008 in 3 hospitals. We investigated the incidence and clinical course of ARF in SAP patients. Then, we compared morbidity and mortality between the patients with ARF and normal renal function (NRF). RESULTS: Of the total 102 SAP patients, ARF was observed in 39 patients (38.2%). The peak serum creatinine level in ARF patients was 4.5+/-2.3 mg/dL. Eight of the 39 ARF patients (20.5%) received hemodialysis and ten patients (25.6%) died. When compared to NRF patiens, ARF patients (n=39) had higher incidence of dyspnea (17.9% vs 3.2%, p=0.011), loss of consciousness (17.9% vs 1.6%, p=0.003), and APACHE II scores more than 8 (92.3% vs 0%, p<0.001). The ARF group had also higher incidences of sepsis (35.9% vs 7.9%, p<0.001), multiorgan failure (15.4% vs 0%, p=0.001), respiratory failure (28.2% vs 4.7%, p=0.001) and mortality (25.6% vs 3.2%, p=0.001). Multivariate analysis demonstrated thrombocytopenia, hemoconcentration, and high LDH as independent risk factors of ARF in SAP patients. CONCLUSION: The incidence of ARF was high (38.2%) and ARF patients showed higher morbidity and mortality, compared to NRF patients. We suggest that early management of ARF should be performed for reducing the mortality in SAP patients.
Acute Kidney Injury ; APACHE ; Creatinine ; Dyspnea ; Humans ; Incidence ; Korea ; Medical Records ; Multivariate Analysis ; Pancreatitis ; Renal Dialysis ; Respiratory Insufficiency ; Retrospective Studies ; Risk Factors ; Sepsis ; Thrombocytopenia ; Unconsciousness