South Korea implemented interventions to curb the spread of the novel coronavirus disease 2019 (COVID-19) pandemic with discovery of the first case in early 2020. Mathematical modeling designed to reflect the dynamics of disease transmission has been shown to be an important tool for responding to COVID-19. This study aimed to review publications on the structure, method, and role of mathematical models focusing on COVID-19 transmission dynamics in Korea. In total, 42 papers published between August 7, 2020 and August 21, 2022 were studied and reviewed. This study highlights the construction and utilization of mathematical models to help craft strategies for predicting the course of an epidemic and evaluating the effectiveness of control strategies. Despite the limitations caused by a lack of available epidemiological and surveillance data, modeling studies could contribute to providing scientific evidence for policymaking by simulating various scenarios.

Background: The purpose of the present study was to assess the daily protein uptake and its relationship with sarcopenia, as defined by the Asian Working Group for Sarcopenia (AWGS), among elderly patients with hip fractures. Methods: Forty-seven elderly patients with hip fractures were enrolled in this retrospective observational study. The main outcome measures included protein uptake, muscle mass, and grip strength for sarcopenia in elderly patients. Sarcopenia was diagnosed according to AWGS. Wholebody densitometry was used to measure skeletal muscle mass, and muscle strength was evaluated using handgrip testing. Results: Of 47 patients with hip fractures (12 men and 35 women), 37 (79%) patients exhibited insufficient protein intake (range, 0.01-0.588 g/kg/day), and 10 (21%) patients exhibited excessive protein intake (range, 1.215-2.121 g/kg/day). The mean daily protein intake was 56.5 g (range, 7.2–136.0 g). Prevalence of low muscle strength (handgrip strength <18 kg in women and <26 kg in men) was detected in 13 (37%) women and 8 (67%) men (P=0.076). Sarcopenia (lower muscle mass and lower muscle strength) was detected in 9 (26%) women and 6 (50%) men (P=0.119). Although lower protein intake was marginally associated with sarcopenia (P=0.189), it was significantly associated with lower grip strength (P=0.042). Conclusions The present study demonstrated that insufficient protein intake in elderly patients with hip fractures was common, and lower protein intake was significantly associated with lower muscle strength.

BACKGROUND/OBJECTIVES: Obesity, characterized by abnormal fat accumulation and metabolic disturbances, presents a significant health challenge. Opuntia humifusa Raf., commonly known as Korean Cheonnyuncho, is rich in various beneficial compounds and has demonstrated antioxidant and anti-inflammatory effects. However, its potential impact on glucose and lipid metabolism, particularly in obese rats, remains unexplored. We aimed to investigate whether O. humifusa stems and fruits could beneficially alter glucose metabolism and lipid profiles in a rat model of high-fat diet (HFD)-induced obesity.MATERIALS/METHODS: Thirty-two rats were allocated into 4 groups: normal diet (NF), HFD control (HF), HFD treated with 2% O. humifusa stems (HF-OS), and HFD treated with 2% O. humifusa fruits (HF-OF). Experimental diets were administered for 6 weeks. At the end of the treatment, liver and fat tissues were isolated, and serum was collected for biochemical analysis. The major flavonoid from O. humifusa stems and fruits was identified and quantified. RESULTS: After 6 weeks of treatment, the serum fasting glucose concentration in the HF-OS group was significantly lower than that in the HF group. Serum fasting insulin concentrations in both HF-OS and HF-OF groups tended to be lower than those in the HF group, indicating a significant improvement in insulin sensitivity in the HF-OS group. Additionally, the HF-OS group exhibited a tendency towards the restoration of adiponectin levels to that of the NF group. CONCLUSION The 2% O. humifusa stems contain abundant quercetin and isorhamnetin, which alter fasting blood glucose levels in rats fed a HFD, leading to a favorable improvement in insulin resistance.

BACKGROUND/OBJECTIVES: Obesity, characterized by abnormal fat accumulation and metabolic disturbances, presents a significant health challenge. Opuntia humifusa Raf., commonly known as Korean Cheonnyuncho, is rich in various beneficial compounds and has demonstrated antioxidant and anti-inflammatory effects. However, its potential impact on glucose and lipid metabolism, particularly in obese rats, remains unexplored. We aimed to investigate whether O. humifusa stems and fruits could beneficially alter glucose metabolism and lipid profiles in a rat model of high-fat diet (HFD)-induced obesity.MATERIALS/METHODS: Thirty-two rats were allocated into 4 groups: normal diet (NF), HFD control (HF), HFD treated with 2% O. humifusa stems (HF-OS), and HFD treated with 2% O. humifusa fruits (HF-OF). Experimental diets were administered for 6 weeks. At the end of the treatment, liver and fat tissues were isolated, and serum was collected for biochemical analysis. The major flavonoid from O. humifusa stems and fruits was identified and quantified. RESULTS: After 6 weeks of treatment, the serum fasting glucose concentration in the HF-OS group was significantly lower than that in the HF group. Serum fasting insulin concentrations in both HF-OS and HF-OF groups tended to be lower than those in the HF group, indicating a significant improvement in insulin sensitivity in the HF-OS group. Additionally, the HF-OS group exhibited a tendency towards the restoration of adiponectin levels to that of the NF group. CONCLUSION The 2% O. humifusa stems contain abundant quercetin and isorhamnetin, which alter fasting blood glucose levels in rats fed a HFD, leading to a favorable improvement in insulin resistance.

BACKGROUND/OBJECTIVES: Obesity, characterized by abnormal fat accumulation and metabolic disturbances, presents a significant health challenge. Opuntia humifusa Raf., commonly known as Korean Cheonnyuncho, is rich in various beneficial compounds and has demonstrated antioxidant and anti-inflammatory effects. However, its potential impact on glucose and lipid metabolism, particularly in obese rats, remains unexplored. We aimed to investigate whether O. humifusa stems and fruits could beneficially alter glucose metabolism and lipid profiles in a rat model of high-fat diet (HFD)-induced obesity.MATERIALS/METHODS: Thirty-two rats were allocated into 4 groups: normal diet (NF), HFD control (HF), HFD treated with 2% O. humifusa stems (HF-OS), and HFD treated with 2% O. humifusa fruits (HF-OF). Experimental diets were administered for 6 weeks. At the end of the treatment, liver and fat tissues were isolated, and serum was collected for biochemical analysis. The major flavonoid from O. humifusa stems and fruits was identified and quantified. RESULTS: After 6 weeks of treatment, the serum fasting glucose concentration in the HF-OS group was significantly lower than that in the HF group. Serum fasting insulin concentrations in both HF-OS and HF-OF groups tended to be lower than those in the HF group, indicating a significant improvement in insulin sensitivity in the HF-OS group. Additionally, the HF-OS group exhibited a tendency towards the restoration of adiponectin levels to that of the NF group. CONCLUSION The 2% O. humifusa stems contain abundant quercetin and isorhamnetin, which alter fasting blood glucose levels in rats fed a HFD, leading to a favorable improvement in insulin resistance.

BACKGROUND/OBJECTIVES: Obesity, characterized by abnormal fat accumulation and metabolic disturbances, presents a significant health challenge. Opuntia humifusa Raf., commonly known as Korean Cheonnyuncho, is rich in various beneficial compounds and has demonstrated antioxidant and anti-inflammatory effects. However, its potential impact on glucose and lipid metabolism, particularly in obese rats, remains unexplored. We aimed to investigate whether O. humifusa stems and fruits could beneficially alter glucose metabolism and lipid profiles in a rat model of high-fat diet (HFD)-induced obesity.MATERIALS/METHODS: Thirty-two rats were allocated into 4 groups: normal diet (NF), HFD control (HF), HFD treated with 2% O. humifusa stems (HF-OS), and HFD treated with 2% O. humifusa fruits (HF-OF). Experimental diets were administered for 6 weeks. At the end of the treatment, liver and fat tissues were isolated, and serum was collected for biochemical analysis. The major flavonoid from O. humifusa stems and fruits was identified and quantified. RESULTS: After 6 weeks of treatment, the serum fasting glucose concentration in the HF-OS group was significantly lower than that in the HF group. Serum fasting insulin concentrations in both HF-OS and HF-OF groups tended to be lower than those in the HF group, indicating a significant improvement in insulin sensitivity in the HF-OS group. Additionally, the HF-OS group exhibited a tendency towards the restoration of adiponectin levels to that of the NF group. CONCLUSION The 2% O. humifusa stems contain abundant quercetin and isorhamnetin, which alter fasting blood glucose levels in rats fed a HFD, leading to a favorable improvement in insulin resistance.

Three-dimensional (3D) printing technology, with additive manufacturing, can aid in the production of various kinds of patient-specific medical devices and implants in medical fields, which cannot be covered by mass production systems for producing conventional devices/implants. The simulator-based medical image demonstrates the anatomical structure of the disease, which can be used for education, diagnosis, preparation of treatment plan and preoperative surgical guide, etc. The surgical guide is used as a patient-specific medical device for guiding incision, resection, insertion, and marking. As 3D printers can output materials that can be inserted into the human body, the patient-specific implant device that reflects the patient's anatomy and surgical plan could be of relevance. In addition, patient-specific aids, including gibs, splints, prostheses, and epitheses, could be used for a better outcome. Finally, bio-printing is also used to cultivate cells to produce functional artificial tissues.