[Purpose] The purpose of this study was to investigate the effect of riding exercise on hormone levels in normal elderly people who were taught horseback riding for 8 weeks. [Subjects] Subjects were classified into an exercise group (n=10) and control group (n=10). [Methods] The two groups, horseback riding exercise group of 10 and control group of 10, were each tested for 15 minutes, 3 times, over 8 weeks. Post-exercise tests were implemented in both groups in the same way as pre-study tests. [Results] The horseback riding group showed a significant difference in the pre- and post-exercise serotonin and cortisol levels. Additionally, serotonin and cortisol levels showed significant differences between the two groups. [Conclusion] Serotonin and cortisol levels significantly increased in the experimental group, suggesting that horseback riding exercise is effective for improving the levels of these hormones.

Despite of the changes of out-of-hospital cardiac arrest (OHCA) survival rise when bystander CPR is provided, this was only conducted in about 23% of OHCA patients in Korea in 2018. Police officers acting as first responders have a high chance of witnessing situations requiring CPR. We investigated long-term effects on CPR quality between chest compression-only CPR training and conventional CPR training in police officers to find an efficient CPR training method in a prospective, randomized, controlled trial. Police officers underwent randomization and received different CPR training. With the Brayden Pro application, we compared the accuracy of CPR skills immediately after training and the one after 3 months. Right after training, the conventional CPR group presented the accuracy of the CPR skills (compression rate: 74.6%, compression depth: 66.0%, recoil: 78.0%, compression position: 96.1%) and chest compression-only CPR group presented the accuracy of the CPR skills (compression rate: 74.5%, compression depth: 71.6%, recoil: 79.2%, compression position: 99.0%). Overall, both groups showed the good quality of CPR skills and had no meaningful difference right after the training. However, three months after training, overall accuracy of CPR skills decreased, a significant difference between two groups was observed for compression position (conventional CPR: 80.0%, chest compression only CPR: 95.0%). In multiple linear regression analysis, three months after CPR training, chest compression-only CPR training made CPR skills accuracy 28.5% higher. In conclusion, police officers showed good-quality CPR right after CPR training in both groups. But three months later, chest compression-only CPR training group had better retention of CPR skills. Therefore, chest compression-only CPR training is better to be a standard training method for police officers as first responders.

Severe patients visited regional emergency centers more frequently during the COVID-19 period, and disposition status warranting admission to the intensive care unit or resulting in death was more common during the COVID-19 period. This study was conducted to compare the characteristics and severity of patients, and emergency department length of stay before and after the COVID-19 outbreak. Subjects were 75,409 patients who visited the regional emergency medical center from 1 February 2019 to 19 January 2020 and from 1 February 2020 to 19 January 2021. Data was analyzed using the SPSS/WIN 22.0 program. The significance level was p < 0.05. The chi-square test and t-test were used for variables, and Cramer V was used for correlation. We found that the total number of patients visiting the emergency room decreased by 37.6% after COVID-19, but emergency department length of stay among severely ill patients increased by 203.7%. Additionally, the utilization rate of 119 ambulances and relatively more severe patients increased by 9.0% and by 2.1%. More studies about emergency department designs and operational programs should be conducted for better action not only during regular periods but also during periods of pandemic.

Peltophorum pterocarpum is regarded as one of the most important medicinal plants in the traditional medicine system of Vietnam. However, scientific evidence for the antioxidant effects against lipid peroxidation and the potential effects in cancer of this plant are lacking. In our experiments, 70% ethanolic extracts of P. pterocarpum leaves (LPP) and stem bark (SPP) were evaluated for their low-density lipoprotein (LDL) oxidation and cytotoxic activity against cancer cell lines. Both LPP and SPP inhibited Cu²⁺-mediated LDL by increasing the lag time of conjugated diene formation and inhibiting the generation of thiobarbituric acid reactive substances (TBARS) in a dose-dependent manner. In cancer cells, LPP and SPP triggered the most potent cytotoxic effects against human leukemia cells, CRF-SBA and HL-60, with half-maximal inhibitory concentration (IC₅₀) values ranging from 118.5 to 157.2 µg/mL. SPP exhibited significant cytotoxicity against MIA PACA2, A549, and KG cell lines with IC₅₀ values of 167.5, 244.1 and 255.0 µg/mL, respectively. Meanwhile, LPP showed cytotoxic activity against KG with an IC₅₀ value of 228.1 µg/mL. SPP mediated cytotoxicity in HL-60 and CCRF-SBA cells through the activation of the apoptosis pathway, including the activation of caspases 3, and 9 and poly (ADP-ribose) polymerase (PARP). These results suggested that SPP may prevent the development and progression of atherosclerosis and leukemia in humans.

[Purpose] This study applied active rehabilitation therapy to muscular back strength and assessed the subjective pain degree in chronic low back pain patients. [Subjects and Methods] Subjects were randomly assigned to two groups: experimental (n=8) and control (n=8). The experimental group performed two types of rehabilitation therapy programs four times per week for eight weeks. The rehabilitation program was based on the Korea Occupational Safety and Health Agency's program. There were several types of stretching and strengthening. Back strength was measured using the Back Muscle Dynamometer TKK-5402. The visual analog scale score, selected to measure degrees of subjective pain, was used to assess treatment efficacy. [Results] For the experimental group, muscular back strength increased from 133.90 ± 11.84 kg before exercise to 145.59 ± 14.49 kg after exercise. In the control group, muscular back strength decreased from 133.92 ± 3.84 kg before exercise to 133.90 ± 5.81 kg after exercise. In the experimental group, the visual analog scale score for subjective pain decreased from 6.63 ± 0.52 before exercise to 5.75 ± 0.46 after exercise; in the control group, it decreased from 5.61 ± 0.52 before exercise to 5.61 ± 0.52 after exercise. [Conclusion] Active rehabilitation therapy is a positive intervention that can provide relief from back pain.

BACKGROUND:Osteoprotegerin (OPG) is a soluble glycoprotein that belongs to the tumor necrosis factor (TNF) receptor superfamily. OPG is mainly secreted by bone. The relationship between acute resistance training, serum OPG levels and metabolic syndro...