A 'circadian rhythm' is a self-sustained biological rhythm (cycle) that repeats itself approximately every 24 hours. Circadian rhythms are generated by an internal clock, or pacemaker, and persist even in the absence of environmental time cues, collectively termed 'zeitgebers.' Although organisms generate circadian rhythms internally, they are entrained by environmental stimuli, particularly the light-dark cycle. Measurement of the endogenous melatonin rhythm provides relatively reliable surrogate way of assessing the timing of the internal circadian clock. Also, core body temperature and cortisol can be used as markers of circadian rhythms. The sleep-wake cycle, body temperature, and melatonin rhythm have a stable internal phase relationship in humans and other diurnal species. They play an important role in controlling daily behavioral rhythms including task performance, blood pressure, and synthesis and secretion of several hormones. In this review, we address not only the properties, methods of measurement, and markers of circadian rhythms, but also the physiological and psychological importance of human circadian rhythms.
Blood Pressure ; Body Temperature ; Circadian Clocks ; Circadian Rhythm* ; Cues ; Humans ; Hydrocortisone ; Melatonin ; Photoperiod ; Task Performance and Analysis

Cancer-related anorexia-cachexia syndrome (CACS) is a hypercatabolic state, characterized by reduced appetite and weight loss due to ongoing loss of skeletal muscle mass and adipose tissue. CACS occurs mainly in patients with advanced cancer; thus, weight loss in CACS is often associated with poor prognosis and decreased survival. A large number of studies have been conducted on various pharmacologic agents for palliation of cancer-related anorexia. The purpose of this article is to review the pre-existing pharmacologic agents used for CACS and to evaluate the evidence from current studies on each pharmacologic agent. First, appetite stimulants such as corticosteroids, progestins, cyproheptadine, and cannabinoid have been shown to be beneficial by improving appetite and helping with weight changes even if they had no effect on survival rate. Several other agents with anti-inflammatory effects (e.g., eicosapentaenoic acid, thalidomide, and melatonin), prokinetic agents (e.g., metoclopramide), anabolic agents (e.g., androgens and growth hormone), antipsychotics (e.g., mirtazapine and olanzapine), and antiemetics have also been studied in patients in CACS; however further investigations would be required to confirm the beneficial effects.
Adipose Tissue ; Adrenal Cortex Hormones ; Anabolic Agents ; Androgens ; Anorexia ; Antiemetics ; Antipsychotic Agents ; Appetite ; Appetite Stimulants ; Cachexia ; Cyproheptadine ; Eicosapentaenoic Acid ; Glucocorticoids ; Humans ; Muscle, Skeletal ; Progestins ; Prognosis ; Survival Rate ; Thalidomide ; Weight Loss

PURPOSE: Parenteral nutrition (PN) is known to provide therapeutic beneficial improvements in malnourished patients for whom enteral nutrition is not feasible. The objective of this study was to investigate the current clinical characteristics and utilization of PN in Korea. METHODS: We analyzed the Health Insurance Review Agency National Inpatients Sample database from 2014 to 2016, which included 13% of all hospitalized patients in Korea. Adult patients aged 20 years or older and receiving premixed multi-chamber bag containing PN were included for this study. Patient characteristics, admission type, primary diagnosis, and hospital demographics were evaluated. SAS version 9.4 was used for data analysis. RESULTS: From 2014 to 2016, 149,504 patients received premixed PN, with 226,281 PN prescriptions being written. The mean patient age was 65.0 years, and 81,876 patients (54.8%) were male. Premixed 3-chamber bag and 2-chamber bag PN solutions were utilized in 131,808 (88.2%) and 32,033 (21.4%) patients, respectively. The number of patients hospitalized through the emergency department were 70,693 (47.3%), whereas 43,125 patients (28.8%) were administered PN in intensive care units. In the adult PN patients, the highest primary diagnosis was malignant neoplasm of the stomach (8,911, 6.0%), followed by organism unspecified pneumonia (7,008, 4.7%), and gastroenteritis and colitis of unspecified origin (6,381, 4.3%). Overall, 34% of adult PN patients were diagnosed with malignancies, the most common being neoplasm of the stomach (17.7%), neoplasm of bronchus/lung (11.2%), neoplasm of colon (11.1%), and neoplasm of liver/intrahepatic bile ducts (10.0%). PN solutions were most frequently administered in the metropolitan area (55.0%) and in hospitals with more than 1,000 beds (23.6%). CONCLUSION: PN was commonly administered in older patients, with primary diagnosis of malignancy in a significant number of cases. This study is the first large-scale description of PN-prescribing patterns in real-world clinical practice in South Korea.
Adult* ; Bile Ducts ; Colitis ; Colon ; Demography ; Diagnosis ; Emergency Service, Hospital ; Enteral Nutrition ; Gastroenteritis ; Humans ; Inpatients ; Insurance, Health ; Intensive Care Units ; Korea* ; Male ; Nutritional Support ; Parenteral Nutrition* ; Pneumonia ; Prescriptions ; Statistics as Topic ; Stomach

PURPOSE: To evaluate the clinical manifestations of adverse drug reactions (ADRs) of parenteral nutrition (PN) use in Korea. METHODS: The Korean Adverse Event Reporting System (KAERS) database records in 2015 on PN-treated patients were used. ADRs classified as “certain,”“probable,” and “possible” based on the WHO-Uppsala Monitoring Centre criteria were analyzed. RESULTS: In total, 21,436 ADRs from 2,346 patients were included for analysis. The mean patient age was 57.1 years and the mean number of ADRs per patient was 9.1. ADRs were reported frequently with amino acids solutions (682 events, 40.8%), followed by combinations products (519 events, 31.1%), and fat emulsions (363 events, 21.7%). The frequent ADRs were gastrointestinal (507 events, 30.3%), skin (343 events, 20.5%), general disorders (239 events, 14.3%), and central/peripheral nervous system disorders (165 events, 9.9%). The common clinical symptoms were nausea (321 events, 19.2%), vomiting (105 events, 6.3%), and vein pain (102 events, 6.1%). Serious ADRs accounted for 220 patients (9.4%) and dyspnea was the most frequent clinical manifestation. CONCLUSION: This study analyzed the KAERS data in 2015 from patients treated with PN and revealed gastrointestinal and skin disorders to be the leading ADRs.
Amino Acids ; Drug-Related Side Effects and Adverse Reactions ; Dyspnea ; Emulsions ; Humans ; Korea* ; Nausea ; Nervous System Diseases ; Parenteral Nutrition* ; Skin ; Veins ; Vomiting

BACKGROUND: Previous studies have noted that the simultaneous use of sulfonylureas and antimicrobials, which is common, could increase the risk of hypoglycemia. In particular, an age of 65 years or older is a known risk factor for sulfonylurea-related hypoglycemia in hospitalized patients. Therefore, we performed this study to determine the potential risk of hypoglycemia from the concurrent use of antimicrobials and sulfonylureas. METHODS: We performed a cross-sectional study on the National Health Insurance Service-National Sample Cohort from 2013. The eligibility criteria included patients of 65 years of age or older taking a sulfonylurea with 25 different antimicrobials. Different risk ratings of severity in drug-drug interactions (potential DDIs), level X, D, or C in Lexi-Interact™online, and contraindicated, major, or moderate severity level in Micromedex® were included. SAS version 9.4 was used for data analysis. RESULTS: A total of 6,006 elderly patients with 25,613 prescriptions were included. The largest age group was 70 to 74 (32.7%), and 39.7% of patients were men. The mean number of prescriptions was 4.3 per patient. The most frequently used antimicrobials were levofloxacin (6,583, 25.7%), ofloxacin (6,549, 25.6%), fluconazole (4,678, 18.0%), and ciprofloxacin (2,551, 9.8%). Among sulfonylureas, glimepiride was prescribed most frequently, followed by gliclazide, glibenclamide, and glipizide. CONCLUSION: Of the antimicrobials with a high potential of hypoglycemia, levofloxacin, ofloxacin, fluconazole, and ciprofloxacin were used frequently. Thus, the monitoring of clinically relevant interactions is required for patients concurrently administered sulfonylureas and antimicrobials.
Aged* ; Anti-Infective Agents ; Ciprofloxacin ; Cohort Studies ; Cross-Sectional Studies ; Drug Interactions ; Fluconazole ; Gliclazide ; Glipizide ; Glyburide ; Humans ; Hypoglycemia* ; Korea* ; Levofloxacin ; Male ; National Health Programs ; Ofloxacin ; Prescriptions ; Risk Factors ; Statistics as Topic ; Sulfonylurea Compounds

BACKGROUND: 3-Hydroxy-3-methylglutaryl coenzyme A reductase inhibitors (statins) effectively reduce serum levels of low-density lipoprotein (LDL) and total cholesterol. High-intensity statins are recommended for all patients aged ≤75 with clinical atherosclerotic cardiovascular disease (ASCVD), diabetes mellitus aged 40–75 with ≥7.5% estimated 10-year ASCVD risk and LDL-C ≥190 mg/ dL. High-intensity statins associated with more frequent adverse events (AEs) compared to moderate- to low-intensity statins. The aim of this study was to compare AEs between high-intensity and moderate- to low-intensity statin group using the Korea Adverse Event Reporting System (KAERS) database. METHODS: Adults (≥18 years) with statin-associated AEs from July 2009-June 2014 were included. Only AEs classified as “certain”, “probable” and “possible” based on the WHO-Uppsala Monitoring Center criteria were analyzed. RESULTS: In total, 247 AEs from 196 patients [high-intensity statin group (HG), n = 25 (13%); moderate- to lowintensity statin group (MLG), n = 171 (87%)] were included. Mean age was higher in HG compared with MLG (67 ± 14 vs 62 ± 12). The HG showed a significant higher frequency of liver/biliary system disorders (37% vs 14%, p = 0.001). Hepatic function abnormal was reported more frequently in HG compared to MLG (26% vs 9%, p = 0.006). CONCLUSION: According to KAERS data, liver/biliary system disorders were more frequently reported in HG compared to MLG.
Adult ; Cardiovascular Diseases ; Cholesterol ; Coenzyme A ; Diabetes Mellitus ; Humans ; Hydroxymethylglutaryl-CoA Reductase Inhibitors* ; Korea ; Lipoproteins ; Oxidoreductases

This study was performed to review studies carried out in Korea reporting toxic reactions to traditional Chinese medicines (TCMs) as a result of heavy metal contamination. PubMed (1966-August 2013) and International Pharmaceutical Abstracts (1965-August 2013) were searched using the medical subject heading terms of "Medicine, Chinese Traditional," "Medicine, Korean Traditional," "Medicine, Traditional," "Metals, Heavy," and "Drug Contamination". For Korean literature, Korea Med (http://www.koreamed.org), the Korean Medical Database (http://kmbase.medric.or.kr), National Discovery for Science Leaders (www.ndsl.kr), Research Information Sharing Service (http://www.riss.kr), and Google Scholar were searched using the terms "Chinese medicine," "Korean medicine," "herbal medicine," and "metallic contamination" in Korean. Bibliographies of case reports and case series, identified using secondary resources, were also utilized. Only literature describing cases or studies performed in Korea were included. Case reports identified clear issues with heavy metal, particularly lead, contamination of TCMs utilized in Korea. No international standardization guidelines for processing, manufacturing and marketing of herbal products exist. Unacceptably high levels of toxic metals can be present in TCM preparations. Health care providers and patients should be educated on the potential risks associated with TCMs. International advocacy for stricter standardization procedures for production of TCMs is warranted.
*Drug Contamination ; Drugs, Chinese Herbal/*adverse effects/chemistry ; Humans ; Medicine, Chinese Traditional ; Medicine, Korean Traditional ; Metals, Heavy/*poisoning ; *Poisoning ; Republic of Korea ; Risk Assessment

The objective of this study was to develop fermented vegetable juices that possess antidiabetic and antioxidant activities. Lactobacillus plantarum MKHA15 (MKHA15) and Leuconostoc mesenteroides MKSR (MKSR) were applied to ferment onion, cabbage, and tomato juices at 37℃ and 30℃ for 72 h, respectively, and their functionality was tested using the 12 h hour-fermented juice by MKHA15, and 48 h hour-fermented juice by MKSR. Inhibition of α-glucosidase activity was observed in all fermented juices. The onion juice fermented by MKHA15 showed significantly higher α-glucosidase inhibition activity compared to other juices. All juices showed more than 70% inhibition of α-amylase activity. The DPPH radical scavenging activity of onion juice fermented by MKSR showed significantly lower activity than cabbage and tomato juices; however, no difference was observed between the types of starter cultures. The SOD-like activity of cabbage juice fermented by MKSR was the highest among the fermented juices. The juices fermented by MKHA15 showed higher reducing power than those by MKSR. Therefore, we believe that cabbage, onion and tomato juice fermented by MKHA15 and MKSR would be useful in probiotic juices, as they possess antidiabetic and antioxidant activities.
Brassica ; Fruit and Vegetable Juices ; Lactobacillus plantarum ; Lactobacillus ; Leuconostoc ; Lycopersicon esculentum ; Onions ; Probiotics ; Vegetables

The importance of adopting healthy exercise routines has been repeatedly emphasized to individuals with diabetes mellitus (DM). However, knowledge about the risk of exercise-induced hypoglycemia is limited. Regular exercise reduces and delays the onset of DM-related complications particularly in individuals who already have DM. However, an excessive exercise can lead to hypoglycemia. Excessive exercise in the evening can cause hypoglycemia while sleeping. Furthermore, if individuals with DM want to have a greater amount of exercise, the exercise duration rather than intensity must be increased. In weight resistance exercises, it is beneficial to first increase the number of repetitions, followed by the number of sets and gradually the weight of resistance. When performing intermittent high-intensity training within a short time period, hypoglycemia may develop for an extended period after exercise. In addition to adjusting exercise regimens, the medication doses must be modified accordingly. Delaying exercise, adjusting the number of snacks consumed prior to exercise, reducing insulin dose before exercise, and injecting insulin into the abdomen rather than the limbs prevent exercise-induced hypoglycemia prior to a spontaneous exercise. Ultimately, with personal knowledge on how to prevent hypoglycemia, the effects of exercise can be maximized in individuals with DM, and a healthy lifestyle can prevent future complications.

The importance of adopting healthy exercise routines has been repeatedly emphasized to individuals with diabetes mellitus (DM). However, knowledge about the risk of exercise-induced hypoglycemia is limited. Regular exercise reduces and delays the onset of DM-related complications particularly in individuals who already have DM. However, an excessive exercise can lead to hypoglycemia. Excessive exercise in the evening can cause hypoglycemia while sleeping. Furthermore, if individuals with DM want to have a greater amount of exercise, the exercise duration rather than intensity must be increased. In weight resistance exercises, it is beneficial to first increase the number of repetitions, followed by the number of sets and gradually the weight of resistance. When performing intermittent high-intensity training within a short time period, hypoglycemia may develop for an extended period after exercise. In addition to adjusting exercise regimens, the medication doses must be modified accordingly. Delaying exercise, adjusting the number of snacks consumed prior to exercise, reducing insulin dose before exercise, and injecting insulin into the abdomen rather than the limbs prevent exercise-induced hypoglycemia prior to a spontaneous exercise. Ultimately, with personal knowledge on how to prevent hypoglycemia, the effects of exercise can be maximized in individuals with DM, and a healthy lifestyle can prevent future complications.