• Journal of the Korean Society of School Health
• /
• v.29 no.2
• /
• pp.71-80
• /
• 2016

Purpose: The purpose of this study is to examine the association between consuming high-caffeine energy drinks and suicidal ideation in Korean adolescents. Methods: This study used data drawn from the 2015 Korea Youth Risk Behavior Web_Based Survey. The data of 66,068 students in total (33,374 middle school students and 32,694 high school students) were included in the analysis. The $x^2$ test, univariate and multivariate logistic regressions were conducted with the use of SAS 9.3. Results: Adjusted for the variables associated with suicidal ideation, multivariate logistic regression revealed that consuming highly caffeinated energy drinks had a significant effect on suicidal ideation (middle school students, 1~2 times per week: OR=1.24, 3~4 times per week: OR=1.88, 5~6 times per week: OR=2.20, everyday: OR=2.66, high school students, 1~2 times per week: OR=1.26, 3~4 times per week: OR=1.84, 5~6 times per week: OR=2.42, everyday: OR=3.89). Conclusion: This study strongly suggests adolescents be provided with health education and information about consuming an adequate amount of high-caffeine energy drink and the drink's side effects. In addition, regulations and polices on high-caffeine drink intake should be implemented.

• Journal of Korean Society of Water and Wastewater
• /
• v.29 no.3
• /
• pp.407-414
• /
• 2015

The effect of activated carbon particle diameter (i.e. US sieve No. $8{\times}10$ ($d_p{\approx}2.19mm$), $18{\times}20$ ($d_p{\approx}0.92mm$), $50{\times}60$ ($d_p{\approx}0.27mm$) and $170{\times}200$ ($d_p{\approx}0.081mm$) on caffeine adsorption is investigated. BET surface area was increased with decreasing particle diameter ($d_p$), and caffeine adsorption rates increased with decreasing $d_p$. Moreover, pseudo-second order model is predicted the experimental data more accurately than pseudo-first order model, and the fastest rate constant ($k_2$) was $1.7g\;mg^{-1}min^{-1}$ when $d_p$ was 0.081 mm. Surface diffusion coefficient (Ds) was decreased with decreasing $d_p$ based on the minimum sum of square error (SSE). Practically, certain ranges of Ds are acceptable with high reliability ($R^2$) and it is determined that the effect of $d_p$ on Ds is unclear. The effect of pH on caffeine adsorption indicated the dependency of m/L ratio (mass liquid ratio) and $pH_{pzc}$. The $pH_{pzc}$ (i.e. $7.9{\pm}0.2$) was not affected by $d_p$. The higher caffeine adsorption at pH 4 and pH 7 than at pH 10 is due to $pH_{pzc}$, not $pk_a$ of caffeine.

• Journal of Life Science
• /
• v.14 no.5
• /
• pp.741-746
• /
• 2004

This study investigated the response of GLUT-4 and GRP-78 protein expression in soleus muscle of Streptozotocin-induced diabetic rats with caffeine oral administration by imposing different exercise intensities. Rats were randomly divided into 5 groups (n=6 in each group): diabetic group (D), diabetic-caffeine group (DC), diabetic-caffeine group with low intensity exercise (DCL), diabetic-caffeine group with moderate intensity exercise (DCM) and diabetic-caffeine group with high intensity exercise (DCH). The rats in DCL, DCM and DCH groups were exercised acutely by treadmill running for 8 meter/m, 16 meter/m and 25 meter/m, respectively. Little difference in GLUT-4 protein expression was shown in DC and DCL compared to D. GLUT-4 protein expression was decreased in DCM and increased in DCH was observed. GRP-78 protein expressions in DCL, DCM and DCH were little lower than that of D. An increase in GRP-78 protein was observed in DC. Improved insulin sensitivity with acute high intensity exercise gives the rats important therapy that lowers insulin requirement. This improvement of insulin sensitivity for glucose transport in skeletal muscle results from translocation of the GLUT-4 protein from the endoplasmic reticilum to the cell surface and increase in total quantity of GLUT-4 protein. It is not clear what mechanism reduced GRP-78 protein level in exercise group. It is merely conjectured that caffeine-induced lipolysis provided cells with energy in abundance and this relieved stress which cells are subjected to receive when performing exercise.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.21 no.6
• /
• pp.595-600
• /
• 1992

This study was performed to investigate the effects of dietary protein levels(5% and 15% PEP), caffeine or green tea powder on body fat deposition in rats. Male weanling Wistar rats weighting the average of 90g were allotted into 6 experimental groups, each of which was fed two different levels of dietary protein with or without caffeine or green tea powder(5p+0.15% caffeine ; 5p+6.1% green tea powder ; 15p+0.15% caffeine ; 15p+6.1% green tea powder) during 8 weeks of the experimental period. Caffeine and green tea powder were supplemented at the levels of 0.15% and 6.1% of experimental diets. The rats fed 5% PEP diet which had received caffeine or green tea powder showed significantly(p<0.01) reduced gain in body weight. The food efficiency of which rats fed both 5% and 15% PEP diet supplemented with 6.1% green tea powder was significantly low(p<0.05, respectively) compared with the control group. Rats fed diets containing 0.15% caffeine and 6.1% green tea powder showed the significant reduction(p<0.01) of hite adipose tissue weight, triglycerides levels of liver and plasma. The addition of 0.15% caffeine or 6.1% green tea powder to 5% PEP diet resulted in significantly(p<0.01) higher levels of plasma total cholesterol, free cholesterol, cholesterol ester, but HDL-cholesterol levels were significantly(p<0.01, in 5% PEP group) high. The atherogenic index(Tchol-HDLchol/HDLchol) in rats fed 6.1% green tea powder diets decreased especially compared with the control group.

• Korean Journal of Clinical Pharmacy
• /
• v.24 no.2
• /
• pp.144-153
• /
• 2014

Purpose: This study aimed to investigate the correlation between the health behaviors and the aggression in Korean high school students. Methods: This was a cross-sectional study conducted with a survey of 2,676 high school students. Aggression was measured in four categories (physical aggression, verbal aggression, anger and hostility) using the Aggression Questionnaire, a modified hostility inventory by Buss and Perry. Result: Univariate analysis showed that sex, smoking, alcohol, caffeine, pain pills and gastrointestinal drugs were significantly associated with aggression scores. Boys scored higher than girls in terms of physical and verbal aggression. With respect to the habit of self-medication, students who took pain pills in the last 30 days revealed higher scores in all four aggressive constructs. From multivariate analysis, it was found that alcohol, caffeine, smoking, pain pills, sex and gastrointestinal drugs were independently associated with total aggression score in the order of importance. Alcohol and caffeine, among these factors, had strong correlation with all aggressive characteristics. Conclusion: This study identified a consistent association between the aggression of the students and health behavioral factors, but causal relationship remains to be proven.

• Journal of Embryo Transfer
• /
• v.32 no.3
• /
• pp.131-138
• /
• 2017

In most mammals, metaphase II (MII) oocytes having high maturation promoting factor (MPF) activity have been considered as good oocytes and then used for assisted reproductive technologies including somatic cell nuclear transfer (SCNT). Caffeine increases MPF activity in mammalian oocytes by inhibiting p34cdc2 phosphorylation. The objective of this study was to investigate the effects of caffeine treatment during in vitro maturation (IVM) on oocyte maturation and embryonic development after SCNT in pigs. To this end, morphologically good (MGCOCs) and poor oocytes (MPCOCs) based on the thickness of cumulus cell layer were untreated or treated with 2.5 mM caffeine during 22-42, 34-42, or 38-42 h of IVM according to the experimental design. Caffeine treatment for 20 h during 22-42 h of IVM significantly inhibited nuclear maturation compared to no treatment. Blastocyst formation of SCNT embryos was not influenced by the caffeine treatment during 38-42 h of IVM in MGCOCs (41.1-42.1%) but was significantly improved in MPCOCs compared to no treatment (43.4 vs. 30.1%, P<0.05). No significant effects of caffeine treatment was observed in embryo cleavage (78.7-88.0%) and mean cell number in blastocyst (38.7-43.5 cells). The MPF activity of MII oocytes in terms of p34cdc2 kinase activity was not influenced by the caffeine treatment in MGCOCs (160.4 vs. 194.3 pg/ml) but significantly increased in MPCOCs (133.9 vs. 204.8 pg/ml). Our results demonstrate that caffeine treatment during 38-42 h of IVM improves developmental competence of SCNT embryos derived from MPCOCs by influencing cytoplasmic maturation including increased MPF activity in IVM oocytes in pigs.

• Journal of Plant Biotechnology
• /
• v.31 no.1
• /
• pp.73-78
• /
• 2004

This study was carried out to develop an in vitro chromosome doubling systems for the breeding of tetraploid lily cultivar. Different concentration (ppm) and treatment time (hour) of colchicine, oryzalin and caffeine were compared for the efficiency of bulb regeneration and tetraploidization. The occurrence of tetraploid plants by colchicine was the highest in the concentration of 1,000 ppm for three hours. In oryzalin treatment, the best combination was at 30 ppm for three hours. However, the effects of oryzalin treatments were similar between 10 ppm and 30 ppm concentrations. The survival rate was dramatically reduced in a high concentration of caffeine although some treatments had a higher tetraploid induction. As a consequence, reliable results for the tetraploid production were obtained in the treatments of 1,000 ppm colchicine, 3,000 ppm oryzalin both for three hours, and 9,000 ppm caffeine for nine hours.

• Journal of Embryo Transfer
• /
• v.23 no.1
• /
• pp.31-36
• /
• 2008

We attempted to control the maturation promoting factors (MPF) activity and nuclear remodeling of somatic cell nuclear transfer (NT) bovine embryos. Bovine ear skin fibroblasts were fused to enucleated oocytes treated with either 5 mM caffeine for 2.5 h or 0.5 mM vanadate for 0.5 h and activated. The nuclear remodeling type of the reconstituted embryos was evaluated 1.5 h after activation. MPF activity was assessed in enucleated and chemical treated oocytes before the injection of a donor cell. Effect of chemicals on the embryonic development was evaluated with parthenogenetic embryos. MPF activity increased significantly by caffeine treatment, but decreased by vanadate treatment (p<0.05). Caffeine or vanadate had no deleterious effect on the parthenogenetic embryo development. In caffeine treated group, premature chromosome condensation (PCC) was occurred in 72.2% of NT embryos (p<0.05). In contrast, vanadate induced the formation of a pronucleus-like structure (PN) in a high frequency (68.9%, p<0.05) without PCC (NPCC). Blastocyst development of NT embryos increased by treating with caffeine (30.3%), whereas decreased by treating with vanadate (11.4%) compared to control (22.1%, p<0.05). The results indicate that caffeine or vanadate can control of MPF activity and remodeling type of NT embryos, resulting in the increased or decreased in vitro development.

• Korean Journal of Animal Reproduction
• /
• v.14 no.4
• /
• pp.245-252
• /
• 1990

This study was carried out to investigate the factors affecting fertilization in vitro of follicular oocytes with frozen-thawed spermatozoa in Korean Native Cattle. The bovine ovaries were obtained at a slaughter house and the follicular oocytes were recovered by aspirating the follicular fluid from the visible follicles of 3~6mm. The bovine oocytes were matured in vitro for 20~24 hours in TCM-199 containing FCS and hormones. The matured oocytes were fertilized in vitro using Percoll-separated frozen-thawed spermatozoa in BO solution. The effects of dilution and fertilization media, capacitating method, concentration of inseminated sperm and time after insemination of fertilization, were observed. The results obtained are summarized as follows : 1. The fertilization rate of frozen-thawed sperm inseminated in BO solution with caffeine and heparin together(56.4%) was higher than that of sperm inseminated in BO solution with either caffeine(10.5%) or heparin(8.9%) and without both caffeine and heparin(0%)(P<0.05). 2. The fertilization rate(56.3%) of frozen-thawed sperm inseminated in BO solution with both caffeine and heparin without preincubation was higher than that of sperm preincubated(2.9%)(P<0.05). 3. The fertilization with high concentration of frozen-thawed sperm(1.4~1.8$\times$107cells/ml) in BO solution containing caffeine and heparin resulted in higher fertilization rate, 76.7%, than the low concentration of sperm(0.8~1.0$\times$107cells/ml), 32.7%(P<0.01). 4. When the oocytes were inseminated with frozen-thawed sperm in BO solution containing caffeine and heparin without preincubation, fertilization rate increased by time and the rates were 5.9, 46.0 and 59.4% at 8, 16 and 24 hours, respectively.

• The korean journal of orthodontics
• /
• v.32 no.2 s.91
• /
• pp.129-142
• /
• 2002

The purpose of this study was to evaluate the effects of caffeine and calcium on the activities of the osteoblastic cell from mouse calvaria. The author cultured osteoblastic cells obtained from the mouse calvaria and were divided into three groups : the caffeine-treated, the calcium-treated and the combine-treated group. In caffeine-treated group, the cell toxicity was measured by MTT assay at 1, 2 and 4 days after treatment of caffeine. In all groups, the densities of the mineralized bone nodules were measured by imaging analyzer after Von Kossa staining. The alkaline phosphotase (ALP) activities were measured at 2, 7, 14, 21 and 28 days and the interleukin-1 ${\beta}$ activities at 48 hours after treatment of caffeine and calcium. The measurements were statistically executed with ANOVA test and the results were as follows. 1. The cellular toxicity of the caffeine increased with the concentration of caffeine during the incubation period. 2. The maximum densities of mineralization were observed at 0.2 mM caffeine-treated group, 1.2 mM calcium-treated group, 0.1 mM caffeine and 1.8 mM calcium-treated group. 3. The activities of ALP were peaked at 14 days at calcium-treated group as no-treated. But, the activities of ALP increased with concentrations of caffeine at caffeine-treated group. At combine-treated group, the act of ALP were peaked at 24 days at 1.2 mM, 1.8 mM calcium-treated group, But decreased at 2.5 mM calcium-treated group. 4. The activites of the IL-1 ${\beta}$ were increased significantly at 0.2 mM caffeine-treated group, 1.8 mM calcium-treated group and 0.1 mM caffeine and 1.8 mM calcium-treated group. But, they were decreased at all groups of high concentration.