• Applied Biological Chemistry
• /
• v.38 no.4
• /
• pp.353-358
• /
• 1995

The influence of dry-heat treatment($130{\sim}220^{\circ}C$) on the gelatinization and rheological properties of corn starch(11.4% moisture) was examined. The enthalpy of gelatinization measured by differential scanning calorimetry decreased above $190^{\circ}C$. The viscosity of starch by alkali gelatinization increased as the heating temperature rised. All the values including peak viscosity on amylograms and shear stress, apparent viscosity, consistency index and yield stress of thermal-gelatinized starch dispersion showed decreasing tendencies with increasing of heating temperature from above $170^{\circ}C$ compared with those of raw starch. The apparent viscosity and yield stress of all the samples thermal-gelatinized at $90^{\circ}C$ were increased considerably with process of gelatinization time and especially their rapid increase at the early stage was observed in the $190^{\circ}C$ sample. But all the rheological parameters of $220^{\circ}C$ sample recorded very low values compared with those of the others.

• Applied Biological Chemistry
• /
• v.43 no.4
• /
• pp.231-235
• /
• 2000

The changes of calmodulin levels, calmodulin-binding proteins, and $Ca^{2+}$/calmodulin-dependent glutamate decarboxylase during the growth of tobacco suspension cells were investigated. Tobacco cells exhibited a typical growth curve, including an exponential growth phase between 3 and 5 days after inoculation, and an apparent stationary phase occurring after 5 day. Although slight changes were observed from sample to sample, calmodulin protein levels remained similar during the phases of culture growth. Several $Ca^{2+}-dependent$ calmodulin-binding proteins including 56, 46, 36, and 32-kDa proteins were detected in tobacco cell extracts. The 56-kDa protein was identified as glutamate decarboxylase by Western-blot analysis using an anti-GAD monoclonal antibody. The levels of GAD protein and the specific activity of GAD enzyme were highest during the middle exponential phase of the culture growth cycle. These data suggest that $Ca^{2+}$/calmodulin-dependent glutamate decarboxylase is modulated during the growth of tobacco suspension cells.

• Korean Journal of Biological Psychiatry
• /
• v.16 no.3
• /
• pp.170-180
• /
• 2009

Objectives : To assess clinical improvement and change in plasma brain-derived neurotrophic factor(BDNF) level after repetitive transcranial magnetic stimulation(rTMS) in patients with treatment-resistant schizophrenia. Methods : Seven patients with DSM-IV schizophrenia, who were proven to be treatment-resistant, were treated with 15 sessions of rTMS for three weeks as an adjuvant therapy to antipsychotic treatment. Clinical improvement and change in plasma BDNF level were measured after the treatment period. The symptom severity was assessed with the Positive and Negative Syndrome Scale(PANSS) and the Korean Version of Calgary Depression Scale for Schizophrenia(K-CDSS) at baseline and 7 days after the treatment. Plasma BDNF level was measured by enzyme-linked immunosorbent assay(ELISA) at baseline and 7 days after the treatment. Results : After the rTMS treatment, there was no significant improvement in PANSS total score(Z=-1.693, p=0.090) and no significant change in plasma BDNF was found(Z=-1.183, p=0.237). Negative correlations were found between percentage change in PANSS positive subscale score and duration of illness(rho=-0.991, N=7, p<0.0005, two-tailed), and PANSS negative subscale score at baseline and percentage change in plasma BDNF level(rho=-0.821, N=7, p=0.023, two-tailed). Conclusion : This preliminary study suggests that rTMS didn't make a significant change in clinical symptoms nor in plasma BDNF level in treatment-resistant schizophrenia. Percentage change in plasma BDNF, however, might be correlated with treatment resistance in schizophrenic patients. This is a pilot study with a small sample size, therefore, a further study with a larger sample size is needed.

• Korean Journal of Biological Psychiatry
• /
• v.24 no.1
• /
• pp.10-18
• /
• 2017

Occupational hazards of firefighting and rescue works include frequent exposure to emergencies and life-threatening situations. These stressful work conditions of being constantly under pressure and exposed to potentially traumatic events put them at higher risk of developing posttraumatic stress disorder (PTSD), compared to the general population. PTSD is a potentially debilitating mental disorder, due to persistent intrusive thoughts, negative alterations of mood and cognition, hypervigilance, avoidance of similar situations and reminders, and re-experiences of the traumatic event. Previous studies have shown a relatively high prevalence of PTSD among firefighters, indicating the need for a systematic approach of early detection and prevention. Therefore, a critical review of the current literature on PTSD in firefighters would provide valuable insights into developing effective prevention and intervention programs. Literature indicated that there are risk factors of PTSD in firefighters, such as pre-existing depression, anxiety, sleep disorders, occupational stress, physical symptoms, and binge drinking, whereas social support and adequate rewards are protective factors. Although there are differences in the prevalence of PTSD across studies, partly due to various assessment tools utilized, different sample sizes, and sample characteristics, over one tenth of the firefighters were estimated to have PTSD. The current review warrants further investigations to precisely assess PTSD and co-morbid mental disorders, functional outcomes, and associated factors, and to develop evidence-based preventive and interventional programs to help firefighters with PTSD.

• 한국초전도학회:학술대회논문집
• /
• v.10
• /
• pp.7-7
• /
• 2000

A high $T_c$ SQUID system is developed for the application to biological immunoassay. In this application, magnetic nanoparticles are used as magnetic markers to perform immunoassay, i.e., to detect binding reaction between an antigen and its antibody. The antibody is labeled with ${\gamma}-Fe_2O_3\;(or\;Fe_3O_4)$ nanoparticles, and the binding reaction can be magnetically detected by measuring the magnetic field from the nanoparticles. Design and set up of the system is described. The system consists of (1) SQUID magnetometer or gradiometer made of 30-deg. bicrystal junctions, (2) field and compensation coils to apply the magnetic field of about 1 mT, (3) special Dewar to realize a 2 mm-distance between the SQUID and the sample, (4) two layers of cylindrical shielding to reduce the extemal magnetic noise to about 1/100, and (5) an electric slider to move the sample with a speed of 10 mm/sec. The sensitivity of the system is studied in terms of detectable magnetic flux. For the measurement bandwidth from 0.2 Hz to 10 Hz, minimum-detectable amplitude of the magnetic flux is $0.8\;m\;{\Phi}_o$ and $0.25\;m{\Phi}_o$ for the magnetometer and the gradiometer, respectively, when the magnetic field of 1 mT is applied. The difference between them is due to the residual environmental noise, and the applied magnetic field does not increase the system noise. The corresponding weight of the magnetic markers is 1 ng and 310 pg, respectively. An experiment is also conducted to measure antigen-antibody reaction with the present system. It is shown that the sensitivity of the present system is 10 times better than that of the conventional method using an optical marker. A one order of magnitude improvement of sensitivity will be realized by the sophistication of the present system.

• Journal of Korean Biological Nursing Science
• /
• v.1 no.1
• /
• pp.56-70
• /
• 1999

The purpose of this study was to determine the effect of physical activity on bone mineral density(BMD), and osteoporosis risk factors in Korean women. A convenience sample of 115 women completed the survey questionnaire which included the items of physical activity, osteoporosis risk facors, and demographic background. Distal radial BMD was evaluated using DTX-200. The data were analyzed using frequency, percentage, t-test, Pearson Correlation Coefficient, logistic regression, ANOVA, stepwise multiple regression by SPSS WIN. The sample ranged in age from 31 to 78 years(mean=47.67 old). 91.8% were married, 72.2% were housewives, and mean monthly income was 1,094,900won. Mean explain of the women was 1.21MET, and 50.4% of the women were in the physically inactive group. Brisk walking and mountain climbing were frequently cited activities. 1.8% of the subjects smoked, and 27.5% used alcohol. Average daily intake of milk was 1.17 cups and that of caffeine, 1.13 cups. Age, body weight, monthly income, BMI, education level, duration after menopause, menstration status and caffeine. intake were correlated with BMD. In the relationship between the physical activity and BMD, the physically active group showed a higher level of BMD than the physically inactive group. Significant MET decreased was noted with an age increase. In the stepwise multiple regression analysis, body weight, duration after menopause, and the number of children were identified as the most important risk factors. Conclusively, physical activity could be a beneficial effect in the reduction of osteoporosis in Korean women, considering a positive relationship between physical activity and radial BMD.

• Korean Journal of Biological Psychiatry
• /
• v.23 no.4
• /
• pp.157-165
• /
• 2016

Objectives There were previous studies which indicated that attitude toward suicide is able to influence the suicide outcome in both individual and group levels. In regard to the highest suicide rate in Korea, our study aims to explore the influence that attitude toward suicide has on suicide by comparing the national attitude towards suicide with a representative sample of the general population. Methods The target population was 20- to 59-year-old adults from South Korea, Japan, and the United States. The panel data were divided according to gender, age, and residential area of individuals, and an email with a hyperlink to our web survey was sent to the randomly selected participants in each stratum. To measure the perceptual differences about suicide in different cultures, this study adopted the Attitudes Toward Suicide questionnaire. Results A total of 2247 subjects in three countries participated in this study. According to results from factor analysis, there were different structure of factors and included items within factors in the three countries : five factors with nineteen items in South Korea, five factors with nineteen items in the United States, and five factors with twenty-five items in Japan. With regard to permissive attitude toward suicide, the mean value of permissiveness was not significantly different among countries, but permissiveness according to education level, gender, and marital status was different in each country. Conclusions This study is the first nationwide comparative study about attitude toward suicide with a representative sample. Our findings suggest that permissive attitude toward suicide influence the suicide phenomenon in each country ; however, its impact is not a mean score of permissiveness, but the detailed difference by various demographics.

• Progress in Medical Physics
• /
• v.24 no.3
• /
• pp.140-144
• /
• 2013

In this research, the glass dosimeter was calibrated to measure the standard absorbed dose of the Cs-137 irradiator and absorbed dose in a biological sample. Absorbed dose in water for Cs-137 gamma ray was determined by the IAEA TRS-277 protocol. The PTW-TM30013 ion chamber and the PTW-TM41023 water phantom were utilized for measuring absorbed dose and the value was compared with the reading from DoseAce GD-302M glass dosimeter from Asahi Techno Glass Corporation for its calibration. The uncertainty of measurement ($1{\sigma}$) of the calibrated glass dosimeter was 2.7% and this result would be applied to improve the accuracy in measurement of absorbed dose in a biological sample.

• Applied Chemistry for Engineering
• /
• v.20 no.6
• /
• pp.681-684
• /
• 2009

The turbidity of flow type samples has a nonlinear relation to brightness of laser scattered light, but the shape of images in laser scattered light is different from each turbidity samples. The turbidity measurement will be easy if it uses a pattern of images in laser scattered light. But the excessive analysis load comes from the turbidity measured by red, green, blue intensity (intensity) of all pixels of images in laser scattered light. Therefore the images in laser scattered light were divided by appropriate block to decrease excessive analysis load. The shape of divided images in laser scattered light was different from each turbidity sample. The real turbidity has a linear relation to turbidity measured by the artificial neural network learned with the intensity of divided images in laser scattered light and turbidity.

• Applied Biological Chemistry
• /
• v.38 no.2
• /
• pp.95-99
• /
• 1995

The distribution of lactic acid bacteria and total bacteria in 27 samples of Nuruk (traditional Korean rice wine starter) were investigated, and lactic acid bacteria isolated from those samples were identified. The average number of lactic acid bacteria and total bacteria were $2,11{\times}10^7$ and $2.08{\times}10^8\;cfu/g$, respectively. There was no appreciable differences in the number of lactic acid bacteria among those samples, meanwhile the number of total bacteria varied significantly from sample to sample. Among the lactic acid bacteria, more cocci were counted than rods in those samples. Thirty-two strains of lactic acid bacteria obtained from those samples were identified as Leuconostoc mesenteroides subsp. mesenteroides (11 strains), Pediococcus acidilactici (7 strains), Lactobacillus plantarum (3 strains), L. murinus (7 strains) and Enterococcus faecium (4 strains).