Associations between anterior cingulate cortex glutamate and gamma-aminobutyric acid concentrations and the harm avoidance temperament

Converging lines of evidence have suggested that the personality traits might have neurobiological underpinnings. The anterior cingulate cortex (ACC) has been implicated to play an important role in the human fear and anxiety. Functional and structural characteristics of ACC have been suggested to be associated with the harm avoidance (HA) temperament, one of the important temperament dimensions. Therefore, we aimed to investigate correlations between neurometabolite concentrations in ACC, specifically glutamate and gamma-aminobutyric acid (GABA), which are major excitatory and inhibitory neurotransmitters, respectively, and HA scores. Neurometabolite concentrations were measured using high resolution single voxel proton magnetic resonance spectroscopy ((1)H-MRS), and the HA temperament was evaluated using the Temperament and Character Inventory (TCI). Correlations between HA scores from 37 participants (21 men/16 women, age of 30.3+/-7.0) and glutamate and GABA concentrations in the mid-ACC region were evaluated. HA scores correlated negatively with glutamate concentrations in ACC (partial correlation, R=-0.54, df=33, P=0.001) and positively with GABA concentrations in ACC (partial correlation, R=0.48, df=30, P=0.005). These findings suggest that glutamate and GABA concentrations in ACC are closely related to levels of the HA temperament in healthy subjects.

Reliability and validity of the Korean version of the Impact of Event Scale-Revised

OBJECTIVES

The aim of this study was to explore the reliability and validity of the Impact of Event Scale-Revised Korean version (IES-R-K), a self-report scale for assessment of posttraumatic stress disorder (PTSD).

METHODS

The original Impact of Event Scale-Revised was translated into Korean, and the comparability of content was verified through back-translation procedures. This multicenter study included 93 patients with PTSD, 73 nonpsychotic psychiatric patients, and 88 healthy controls drawn from 18 hospitals across the country. The subjects were assessed using IES-R-K, Clinician-Administered PTSD Scale (CAPS), Beck Depression Inventory, and State Trait Anxiety Inventory (STAI; state anxiety subscale [STAI-S], trait anxiety subscale [STAI-T]) scales.

RESULTS

In the reliability test, Cronbach alpha coefficient and test-retest reliability were .93 and 0.91, respectively, indicating that the IES-R-K has good internal consistency. One-way analysis of variance revealed significant differences in IES-R-K scores among the patients with PTSD, nonpsychotic psychiatric patients, and healthy controls (F = 139.1, P < .001). Duncan post hoc test showed the significant differences among the 3 groups. To assess the validity of the IES-R-K, correlation coefficient between the IES-R-K and CAPS, STAI-S, and STAI-T was calculated. We found that there was a relatively high degree of correlation between the IES-R-K and CAPS (r = 0.92, P < .001). However, there was a relatively less degree of correlation between STAI-S and STAI-T and IES-R-K (r = 0.30, P < .001). Taken these together, IES-R-K showed good discriminant validity.

CONCLUSION

The IES-R-K showed good reliability and validity for the assessment of PTSD symptom severity. The IES-R-K is a useful instrument for assessing PTSD symptoms in Korea.

Accelerometer signal-based human activity recognition using augmented autoregressive model coefficients and artificial neural nets

Automatic recognition of human activities is one of the important and challenging research areas in proactive and ubiquitous computing. In this work, we present some preliminary results of recognizing human activities using augmented features extracted from the activity signals measured using a single triaxial accelerometer sensor and artificial neural nets. The features include autoregressive (AR) modeling coefficients of activity signals, signal magnitude areas (SMA), and title angles (TA). We have recognized four human activities using AR coefficients (ARC) only, ARC with SMA, and ARC with SMA and TA. With the last augmented features, we have achieved the recognition rate above 99% for all four activities including lying, standing, walking, and running. With our proposed technique, real time recognition of some human activities is possible.

3-D diffusion tensor MRI anisotropy content-adaptive finite element head model generation for bioelectromagnetic imaging

Realistic finite element (FE) head models have been successfully applied to bioelectromagnetic problems due to a realistic representation of arbitrary head geometry with inclusion of anisotropic material properties. In this paper, we propose a new automatic FE mesh generation scheme to generate a diffusion tensor MRI (DT-MRI) white matter anisotropy content-adaptive FE head model. We term this kind of mesh as wMesh. With this meshing technique, the anisotropic electrical conductivities derived from DT-MRIs can be best incorporated into the model. The influence of the white matter anisotropy on the EEG forward solutions has been studied via our wMesh head models. The scalp potentials computed from the anisotropic wMesh models against those of the isotropic models have been compared. The results describe that there are substantial changes in the scalp electrical potentials between the isotropic and anisotropic models, indicating that the inclusion of the white matter anisotropy is critical for accurate computation of E/MEG forward and inverse solutions. This fully automatic anisotropy-adaptive wMesh meshing scheme could be useful for modeling of individual-specific FE head models with better incorporation of the white matter anisotropic property towards bioelectromagnetic imaging.

Spatiotemporal human facial expression recognition using fisher independent component analysis and Hidden Markov Model

Facial expression recognition is an essential research area in the field of Human Computer Interface. In this work, we present a spatiotemporal approach of facial expression recognition using image sequences. The system proposed in this paper describes fisher independent component analysis as a feature extractor where the higher order moment classification method (i.e., independent component analysis) is augmented with fisher linear discriminant. This procedure is simply abbreviated as FICA and produces the shape based spatial facial expression features. For recognition, we have utilized Hidden Markov Model (HMM) to learn the obtained spatial features with the temporal dynamics in six different expressions. Our proposed approach for the first time deals with sequential images of emotion-specific facial expression data analyzed with FICA and recognized with HMM. Performance of our proposed system has been compared with four conventional approaches where principal component analysis, generic independent component analysis, enhanced independent component analysis, and augmented principal component analysis with linear discriminant analysis are utilized for feature extraction. Our preliminary results show that our proposed system yields much improved recognition rates reaching the mean recognition rate of 92.85%.

Psychometric validation of the Korean version of Structured Interview for Post-traumatic Stress Disorder (K-SIP)

For diagnosis and management of post-traumatic stress disorder (PTSD), the easily administered assessment tool is essential. Structured Interview for PTSD (SIP) is a validated, 17-item, simple measurement being used widely. We aimed to develop the Korean version of SIP (K-SIP) and investigated its psychometric properties. Ninety-three subjects with PTSD, 73 subjects with mood disorder or anxiety disorder as a psychiatric control group, and 88 subjects as a healthy control group were enrolled in this study. All subjects completed psychometric assessments that included the K-SIP, the Korean versions of the Clinician-Administered PTSD Scale (CAPS) and other assessment tools. The K-SIP presented good internal consistency (Cronbach's alpha=0.92) and test-retest reliability (r=0.87). K-SIP showed strong correlations with CAPS (r=0.72). Among three groups including PTSD patients, psychiatric controls, and normal controls, there were significant differences in the K-SIP total score. The potential cut-off total score of K-SIP was 20 with highest diagnostic efficiency (91.9%). At this point, the sensitivity and specificity were 95.5% and 88.4%, respectively. Our result showed that K-SIP had good reliability and validity. We expect that K-SIP will be used as a simple but structured instrument for assessment of PTSD.

Independent component feature-based human activity recognition via Linear Discriminant Analysis and Hidden Markov Model

In proactive computing, human activity recognition from image sequences is an active research area. This paper presents a novel approach of human activity recognition based on Linear Discriminant Analysis (LDA) of Independent Component (IC) features from shape information. With extracted features, Hidden Markov Model (HMM) is applied for training and recognition. The recognition performance using LDA of IC features has been compared to other approaches including Principle Component Analysis (PCA), LDA of PC, and ICA. The preliminary results show much improved performance in the recognition rate with our proposed method.

Differences in subgingival microflora of Korean and German periodontal patients

PURPOSE

The goal of this study was to characterize the microbiological profile in samples of subgingival plaque taken from periodontal patients with different ethnic origin.

METHODS

178 patients (n=90 from South Korea and n=88 from Germany; age: 45.4 +/- 10.4 years) were diagnosed with severe generalized periodontitis. In all patients the deepest pocket of each quadrant was sampled for subgingival plaque. The four samples per patient were pooled and subsequently analysed with a 16s-RNA-gene probe test.

RESULTS

Prevalence of Aggregatibacter actinomycetemcomitans was significantly higher in German patients (47.7%) compared to Korean patients (26.7%) (p < 0.01, chi(2)-test). For Tannerella forsythia and porphyromonas gingivalis, differences between Germans and Koreans were not as pronounced. A statistically significant difference could also be found for Treponema denticola (Germans: 95.5%, Koreans: 81.1%, p < 0.01, chi(2)-test). After logarithmic transformation, bacterial counts differed for all microorganisms under investigation between Germans and Koreans, even after using a General Linear Model/Analysis of Covariance (GLM/ANCOVA) to adjust for gender, age, smoking status, pocket probing depths (PPD) of sampled teeth, and gingival bleeding index (GBI).

CONCLUSION

Depending on their ethnic origin, the microbiological profile of pooled subgingival plaque sample seems to differ significantly between patients of Caucasian and Asian ethnic origin.

Differential enhancement of leukaemia cell differentiation without elevation of intracellular calcium by plant-derived sesquiterpene lactone compounds

BACKGROUND AND PURPOSE

All-trans retinoic acid (ATRA) induces complete remission in a majority of acute promyelocytic leukaemia patients, but resistance of leukaemic cells to ATRA and its toxicity, such as hypercalcaemia, lead to a limitation of treatment. Therefore, combination therapies with differentiation-enhancing agents at non-toxic concentrations of ATRA may overcome its side effects. Here, we investigated the effect of plant-derived sesquiterpene lactone compounds and their underlying mechanisms in ATRA-induced differentiation of human leukaemia HL-60 cells.

EXPERIMENTAL APPROACH

HL-60 cells were treated with four sesquiterpene lactones (helenalin, costunolide, parthenolide and sclareolide) and cell differentiation was determined by NBT reduction, Giemsa and cytofluorometric analyses. Signalling pathways were assessed by western blotting, gel-shift assay and kinase activity determinations and intracellular calcium levels were determined using a calcium-specific fluorescent probe.

KEY RESULTS

Helenalin, costunolide and parthenolide, but not sclareolide, increased ATRA-induced HL-60 cell differentiation into a granulocytic lineage. Signalling kinases PKC and ERK were involved in the ATRA-induced differentiation enhanced by all of the effective sesquiterpene lactones, but JNK and PI3-K were involved in the ATRA-induced differentiation enhanced by costunolide and parthenolide. Enhancement of cell differentiation closely correlated with inhibition of NF-kappaB DNA-binding activity by all three effective compounds. Importantly, enhancement of differentiation induced by 50 nM ATRA by the sesquiterpene lactones was not accompanied by elevation of basal intracellular calcium concentrations.

CONCLUSIONS AND IMPLICATIONS

These results indicate that plant-derived sesquiterpene lactones may enhance ATRA-mediated cell differentiation through distinct pathways.

Reliability and validity of the Korean version of the Davidson Trauma Scale

The Davidson Trauma Scale (DTS) is a validated, 17-item, brief global assessment scale for posttraumatic stress disorder (PTSD). The purposes of this study were to develop a Korean version of the DTS (DTS-K) while maintaining its basic structure and to evaluate its reliability and validity for the Korean population. Participants of this study included 93 patients with PTSD (PTSD group), 73 patients with nonpsychotic mood or other anxiety disorders (psychiatric control group), and 88 healthy controls (normal control group). Subjects completed psychometric assessments, including the DTS-K and the Korean version of the Clinician-Administered PTSD Scale and the State Trait Anxiety Inventory. The DTS-K showed good internal consistency (Cronbach alpha = .97) and test-retest reliability (r = .93). The DTS-K showed a significantly positive correlation with Clinician-Administered PTSD Scale (r = .94). The highest diagnostic efficiency of DTS-K was at a total score of 47, with sensitivity and specificity of 0.87 and 0.84, respectively. Our findings suggest that the DTS-K is composed of good psychometric properties and is a valid and reliable tool for assessing the frequency and severity of PTSD symptoms regardless of ethnicity.

Changes in the levels of plasma soluble fractalkine in patients with mild cognitive impairment and Alzheimer's disease

Soluble fractalkine plays a distinctive role in the inflammatory processes of the nervous system; however, the role of soluble fractalkine in Alzheimer's disease (AD) has not yet been investigated. In the present study, we evaluated the levels of plasma soluble fractalkine in patients with mild cognitive impairment (MCI), patients with AD and healthy controls. We also investigated the changes in the levels of plasma soluble fractalkine in patients with AD. A total of 102 patients with cognitive impairment, including 51 patients with MCI, 51 patients with AD, and 57 healthy control subjects, were enrolled in this study. The Mini-Mental Status Examination (MMSE) was used to evaluate the severity of cognitive impairment in patients with MCI and AD. The levels of plasma soluble fractalkine were measured using a specific enzyme-linked immunosorbent assay. There were significant group differences in the levels of plasma soluble fractalkine between the MCI, AD, and control groups. Post hoc analyses revealed significant differences between the MCI and control groups, the AD and control groups, and the MCI and AD groups. The level of plasma soluble fractalkine was significantly greater in the patients with mild to moderate AD than in the patients with severe AD. In addition, there was a positive correlation between MMSE score and plasma soluble fractalkine level in the patients with AD. This study provides preliminary evidence that soluble fractalkine is involved in the pathogenesis of AD.

Genetic association of DRD2 polymorphisms with anxiety scores among alcohol-dependent patients

The dopaminergic neurotransmission system is one of the major factors in development of alcoholism and also contributes to anxiety and depression. In this study, the associations of the dopamine receptor type 2 (DRD2) polymorphisms with the symptoms of anxiety were analyzed. A total of 573 alcoholics and 273 controls were enrolled in the study from the Korean population. Five DRD2 SNPs, including -32869 A>G, -32768 insdel C, +11890 C>G, +11915 C>T, and +32806 C>T, were genotyped using a TaqMan assay and analyzed with various alcoholic phenotypes. Although no DRD2 polymorphisms were associated with the risk of alcoholism, +32806C>T and Block2-ht1 showed associations (in dominant models) with both the state anxiety level scale (STAI-S) and the trait anxiety level scale (STAI-T) (P=0.004 and P=0.003, and P=0.01 and P=0.005, respectively). In addition, the -32768 insdel C also showed positive association with both anxiety level scales in recessive models (P=0.01 and P=0.02, respectively).

Psychometric properties of the Korean version of the Short Post-Traumatic Stress Disorder Rating Interview (K-SPRINT)

AIMS

The Short Post-traumatic Stress Disorder (PTSD) Rating Interview (SPRINT) is a validated, eight-item, brief global assessment scale for PTSD. This report investigated the psychometric properties of the Korean version of the SPRINT (K-SPRINT).

METHODS

Eighty-seven PTSD patients, 47 other psychiatric patients, and 63 healthy control subjects were enrolled in the study. All subjects completed a psychometric assessment package that included the K-SPRINT and the Korean versions of the Clinician-Administered PTSD Scale (CAPS), the Beck Depression Inventory (BDI), and the State Trait Anxiety Inventory (STAI).

RESULTS

The K-SPRINT showed good internal consistency (Cronbach's alpha = 0.86) and test-retest reliability (r = 0.82). K-SPRINT showed moderatecorrelations with CAPS (r = 0.71). An exploratory factor analysis produced one K-SPRINT factor. The optimal diagnostic efficiency (91.9%) of the K-SPRINT was found at a total score of 15, at which point the sensitivity and specificity were 90.8% and 92.7%, respectively.

CONCLUSIONS

The present findings demonstrate that the K-SPRINT had good psychometric properties and can be used as a reliable and valid instrument for the assessment of PTSD.

Arc plasma simulation of the KAERI large ion source

The KAERI large ion source, developed for the KSTAR NBI system, recently produced ion beams of 100 keV, 50 A levels in the first half campaign of 2007. These results seem to be the best performance of the present ion source at a maximum available input power of 145 kW. A slight improvement in the ion source is certainly necessary to attain the final goal of an 8 MW ion beam. Firstly, the experimental results were analyzed to differentiate the cause and effect for the insufficient beam currents. Secondly, a zero dimensional simulation was carried out on the ion source plasma to identify which factors control the arc plasma and to find out what improvements can be expected.

An ion optics study for KSTAR neutral beam injector development

Ion optics of three accelerator geometries was studied in terms of an analytic linear optics analysis, a numerical simulation using the IGUN program, an optical multichannel measurement of Doppler-shifted H(alpha) lines, and a water-flow calorimetry on the beam absorbing target. In general, there was a reasonable agreement observed between the four analysis methods and thus the theoretical analyses can be utilized with confidence for design iteration.

Methotrexate, vinblastine, doxorubicin and cisplatin combination regimen as salvage chemotherapy for patients with advanced or metastatic transitional cell carcinoma after failure of gemcitabine and cisplatin chemotherapy

We investigated the safety and efficacy of a methotrexate, vinblastine, doxorubicin and cisplatin (M-VAC) combination regimen as second-line chemotherapy for patients with advanced or metastatic transitional cell carcinoma who failed first-line gemcitabine and cisplatin (GC) chemotherapy. Thirty patients who had progressed or relapsed after GC chemotherapy as first-line treatment were enrolled in this study. The major toxicities were neutropaenia and thrombocytopaenia. A grade 3 or 4 neutropaenia occurred in 19 (63.3%) and a grade 3 or 4 thrombocytopaenia developed in nine patients (30.0%). There were no life-threatening complications during the study. The overall response was 30%. A complete response was achieved in two patients (6.7%) and a partial response in seven (23.3%). The overall disease control rate was 50%. Seven out of 16 patients who had responded previously to GC responded to M-VAC, while 2 out of 14 who had not responded to GC responded to M-VAC. The median response duration was 3.9 months and the median progression-free survival was 5.3 months. The median overall survival was 10.9 months. M-VAC showed encouraging efficacy and reversible toxicities in patients who had progressed after GC chemotherapy and, especially, M-VAC appears to be a reasonable option as a sequential treatment regimen in patients who responded previously to GC chemotherapy.

Birth order and sibling sex ratio in homosexual transsexual South Korean men: Effects of the male-preference stopping rule

Two biodemographic variables - birth order and sibling sex ratio - have been examined in several Western samples of homosexual transsexual men. The results have consistently shown that homosexual transsexuals have a later birth order and come from sibships with an excess of brothers to sisters; the excess of brothers has been largely driven by the number of older brothers and hence has been termed the fraternal birth order effect. In the present study the birth order and sibling sex ratio were examined in an Asian sample of 43 homosexual transsexual men and 49 heterosexual control men from South Korea. Although the transsexual men had a significantly late birth order, so did the control men. Unlike Western samples, the Korean transsexuals had a significant excess of sisters, not brothers, as did the control men, and this was largely accounted for by older sisters. It is concluded that a male-preference stopping rule governing parental reproductive behavior had a strong impact on these two biodemographic variables. Future studies that examine birth order and sibling sex ratio in non-Western samples of transsexuals need to be vigilant for the influential role of stopping rules, including the one identified in the present study.

Manganese superoxide dismutase (MnSOD: Ala-9Val) gene polymorphism may not be associated with schizophrenia and tardive dyskinesia

There has been increasing evidence that the alteration of antioxidant enzymes such as manganese superoxide dismutase (MnSOD) might be implicated in the development of schizophrenia and/or tardive dyskinesia (TD). This study investigated the association of a MnSOD gene (MnSOD) polymorphism (Ala-9Val) with schizophrenia as well as its involvement in TD. Patients with schizophrenia (n=262) and healthy controls (n=263) were enrolled in this study and genotyped by a polymerase chain reaction-based method. The distribution of the MnSOD genotypes and alleles was not significantly different between patients and controls. Logistic regression analysis also failed to reveal any association between MnSOD genotypes and TD. Taken together, these results suggest that the MnSOD polymorphism does not contribute to the development of schizophrenia and/or TD, at least in the Korean population.

Decreased plasma brain-derived neurotrophic factor levels in patients with alcohol dependence

BACKGROUND

Many reports have suggested possible relationships between brain-derived neurotrophic factor (BDNF) and alcohol dependence. A protective effect of BDNF against ethanol-induced cell damage has been suggested, and this effect may contribute to the development or maintenance of alcohol dependence. This study was carried out in order to verify the significance of BDNF in alcohol dependence.

METHODS

Peripheral BDNF levels were measured in alcohol-dependent patients and control subjects using an enzyme-linked immunosorbent assay. A physician's interview and standardized questionnaire were used to obtain information regarding each patient's history of alcohol consumption.

RESULTS

The mean BDNF level was lower in the alcohol dependence group (389.5 +/- 501.7 pg/ml) than in the normal controls (822.5 +/- 420.7 pg/ml) by analysis of covariance (ANCOVA) (F = 25.79, p < 0.01). The mean BDNF level was lower in the alcohol-dependent patients with a positive family history of alcohol dependence (247.6 +/- 289.2 pg/ml) than in those with a negative family history of alcohol dependence (583.9 +/- 652.8 pg/ml) by ANCOVA (F = 6.51, p = 0.01). The BDNF levels did not correlate significantly with any of the variables analyzed in this study, including Beck depression inventory, state and trait anxiety inventory (STAI-S and T), and various drinking behaviors.

CONCLUSIONS

Changes in the levels of BDNF might play a role in the pathophysiology and inheritance of alcohol dependence.

Increased plasma brain-derived neurotrophic factor levels in chronic smokers following unaided smoking cessation

Recent animal studies have suggested an association between nicotine and alterations in brain-derived neurotrophic factor (BDNF) expression levels. However, the role of BDNF in humans with nicotine dependence has not yet been investigated. In this study, we explored the differences in the plasma BDNF levels of chronic smokers and healthy nonsmokers, and we investigated the changes in plasma BDNF levels in chronic smokers following unaided smoking cessation. Forty voluntary participants (20 smokers and 20 nonsmokers) were enrolled in this study. We measured the plasma BDNF levels at baseline (both groups) and at the end of the two-month study period (smoker group only) using an enzyme-linked immunosorbent assay. A total of 12 smokers (60.0%) completed the two-month study. ANCOVA with age and body mass index as covariates showed that the baseline plasma BDNF levels in smokers were significantly lower than those in nonsmokers (F=4.626, p=0.038). The plasma BDNF levels in the smokers significantly increased from baseline after the two-month smoking cessation period (Z=-3.059, p=0.002). These findings suggest that BDNF may play a role in the pathophysiology of smoking behavior.