1.Plasma C-Peptide Levels and the Continuous Glucose Monitoring-Defined Coefficient of Variation in Risk Prediction for Hypoglycemia in Korean People with Diabetes Having Normal and Impaired Kidney Function
So Yoon KWON ; Jiyun PARK ; So Hee PARK ; You-Bin LEE ; Gyuri KIM ; Kyu Yeon HUR ; Jae Hyeon KIM ; Sang-Man JIN
Endocrinology and Metabolism 2025;40(2):268-277
Background:
We aimed to investigate the predictive values of plasma C-peptide levels and the continuous glucose monitoring (CGM)-defined coefficient of variation (CV) in risk prediction for hypoglycemia in Korean people with diabetes with normal and impaired kidney function.
Methods:
We analyzed data from 1,185 participants diagnosed with type 1 and type 2 diabetes who underwent blinded professional CGM between January 2009 and May 2021 at outpatient clinics. We explored correlations among CGM-defined CV, plasma C-peptide levels, and time below range at <70 and 54 mg/dL across different kidney function categories.
Results:
In patients with chronic kidney disease (CKD) stages 1–2 (n=934), 89.3% who had a random plasma C-peptide level higher than 600 pmol/L exhibited a CV of ≤36%. Among those in CKD stage 3 (n=161) with a random plasma C-peptide level exceeding 600 pmol/L, 66.7% showed a CV of ≤36%. In stages 4–5 of CKD (n=90), the correlation between random C-peptide levels and CV was not significant (r=–0.05, P=0.640), including cases with a CV greater than 36% despite very high random plasma C-peptide levels. Random plasma C-peptide levels and CGM-assessed CV significantly predicted hypoglycemia in CKD stages 1–2 and 1–5, respectively.
Conclusion
The established C-peptide criteria in Western populations are applicable to Korean people with diabetes for hypoglycemic risk prediction, unless kidney function is impaired equivalent to CKD stage 3–5. The CGM-defined CV is informative for hypoglycemic risk prediction regardless of kidney function.
2.Quercetin-3-Methyl Ether Induces Early Apoptosis to Overcome HRV1B Immune Evasion, Suppress Viral Replication, and Mitigate Inflammatory Pathogenesis
Jae-Hyoung SONG ; Seo-Hyeon MUN ; Sunil MISHRA ; Seong-Ryeol KIM ; Heejung YANG ; Sun Shim CHOI ; Min-Jung KIM ; Dong-Yeop KIM ; Sungchan CHO ; Youngwook HAM ; Hwa-Jung CHOI ; Won-Jin BAEK ; Yong Soo KWON ; Jae-Hoon CHANG ; Hyun-Jeong KO
Biomolecules & Therapeutics 2025;33(2):388-398
Human rhinovirus (HRV) causes the common cold and exacerbates chronic respiratory diseases, such as asthma and chronic obstructive pulmonary disease. Despite its significant impact on public health, there are currently no approved vaccines or antiviral treatments for HRV infection. Apoptosis is the process through which cells eliminate themselves through the systematic activation of intrinsic death pathways in response to various stimuli. It plays an important role in viral infections and serves as a key immune defense mechanism in the interactions between viruses and the host. In the present study, we investigated the antiviral effects of quercetin-3-methyl ether, a flavonoid isolated from Serratula coronata, on human rhinovirus 1B (HRV1B). Quercetin-3-methyl ether significantly inhibited HRV1B replication in HeLa cells in a concentration-dependent manner, thereby reducing cytopathic effects and viral RNA levels. Time-course and time-of-addition analyses confirmed that quercetin-3-methyl ether exhibited antiviral activity during the early stages of viral infection, potentially targeting the replication and translation phases. Gene expression analysis using microarrays revealed that pro-apoptotic genes were upregulated in quercetin-3-methyl ether-treated cells, suggesting that quercetin-3-methyl ether enhances early apoptosis to counteract HRV1B-induced immune evasion. In vivo administration of quercetin-3-methyl ether to HRV1B-infected mice significantly reduced viral RNA levels and inflammatory cytokine production in the lung tissues. Our findings demonstrated the potential of quercetin-3-methyl ether as a novel antiviral agent against HRV1B, thereby providing a promising therapeutic strategy for the management of HRV1B infections and related complications.
3.Plasma C-Peptide Levels and the Continuous Glucose Monitoring-Defined Coefficient of Variation in Risk Prediction for Hypoglycemia in Korean People with Diabetes Having Normal and Impaired Kidney Function
So Yoon KWON ; Jiyun PARK ; So Hee PARK ; You-Bin LEE ; Gyuri KIM ; Kyu Yeon HUR ; Jae Hyeon KIM ; Sang-Man JIN
Endocrinology and Metabolism 2025;40(2):268-277
Background:
We aimed to investigate the predictive values of plasma C-peptide levels and the continuous glucose monitoring (CGM)-defined coefficient of variation (CV) in risk prediction for hypoglycemia in Korean people with diabetes with normal and impaired kidney function.
Methods:
We analyzed data from 1,185 participants diagnosed with type 1 and type 2 diabetes who underwent blinded professional CGM between January 2009 and May 2021 at outpatient clinics. We explored correlations among CGM-defined CV, plasma C-peptide levels, and time below range at <70 and 54 mg/dL across different kidney function categories.
Results:
In patients with chronic kidney disease (CKD) stages 1–2 (n=934), 89.3% who had a random plasma C-peptide level higher than 600 pmol/L exhibited a CV of ≤36%. Among those in CKD stage 3 (n=161) with a random plasma C-peptide level exceeding 600 pmol/L, 66.7% showed a CV of ≤36%. In stages 4–5 of CKD (n=90), the correlation between random C-peptide levels and CV was not significant (r=–0.05, P=0.640), including cases with a CV greater than 36% despite very high random plasma C-peptide levels. Random plasma C-peptide levels and CGM-assessed CV significantly predicted hypoglycemia in CKD stages 1–2 and 1–5, respectively.
Conclusion
The established C-peptide criteria in Western populations are applicable to Korean people with diabetes for hypoglycemic risk prediction, unless kidney function is impaired equivalent to CKD stage 3–5. The CGM-defined CV is informative for hypoglycemic risk prediction regardless of kidney function.
4.Quercetin-3-Methyl Ether Induces Early Apoptosis to Overcome HRV1B Immune Evasion, Suppress Viral Replication, and Mitigate Inflammatory Pathogenesis
Jae-Hyoung SONG ; Seo-Hyeon MUN ; Sunil MISHRA ; Seong-Ryeol KIM ; Heejung YANG ; Sun Shim CHOI ; Min-Jung KIM ; Dong-Yeop KIM ; Sungchan CHO ; Youngwook HAM ; Hwa-Jung CHOI ; Won-Jin BAEK ; Yong Soo KWON ; Jae-Hoon CHANG ; Hyun-Jeong KO
Biomolecules & Therapeutics 2025;33(2):388-398
Human rhinovirus (HRV) causes the common cold and exacerbates chronic respiratory diseases, such as asthma and chronic obstructive pulmonary disease. Despite its significant impact on public health, there are currently no approved vaccines or antiviral treatments for HRV infection. Apoptosis is the process through which cells eliminate themselves through the systematic activation of intrinsic death pathways in response to various stimuli. It plays an important role in viral infections and serves as a key immune defense mechanism in the interactions between viruses and the host. In the present study, we investigated the antiviral effects of quercetin-3-methyl ether, a flavonoid isolated from Serratula coronata, on human rhinovirus 1B (HRV1B). Quercetin-3-methyl ether significantly inhibited HRV1B replication in HeLa cells in a concentration-dependent manner, thereby reducing cytopathic effects and viral RNA levels. Time-course and time-of-addition analyses confirmed that quercetin-3-methyl ether exhibited antiviral activity during the early stages of viral infection, potentially targeting the replication and translation phases. Gene expression analysis using microarrays revealed that pro-apoptotic genes were upregulated in quercetin-3-methyl ether-treated cells, suggesting that quercetin-3-methyl ether enhances early apoptosis to counteract HRV1B-induced immune evasion. In vivo administration of quercetin-3-methyl ether to HRV1B-infected mice significantly reduced viral RNA levels and inflammatory cytokine production in the lung tissues. Our findings demonstrated the potential of quercetin-3-methyl ether as a novel antiviral agent against HRV1B, thereby providing a promising therapeutic strategy for the management of HRV1B infections and related complications.
5.Plasma C-Peptide Levels and the Continuous Glucose Monitoring-Defined Coefficient of Variation in Risk Prediction for Hypoglycemia in Korean People with Diabetes Having Normal and Impaired Kidney Function
So Yoon KWON ; Jiyun PARK ; So Hee PARK ; You-Bin LEE ; Gyuri KIM ; Kyu Yeon HUR ; Jae Hyeon KIM ; Sang-Man JIN
Endocrinology and Metabolism 2025;40(2):268-277
Background:
We aimed to investigate the predictive values of plasma C-peptide levels and the continuous glucose monitoring (CGM)-defined coefficient of variation (CV) in risk prediction for hypoglycemia in Korean people with diabetes with normal and impaired kidney function.
Methods:
We analyzed data from 1,185 participants diagnosed with type 1 and type 2 diabetes who underwent blinded professional CGM between January 2009 and May 2021 at outpatient clinics. We explored correlations among CGM-defined CV, plasma C-peptide levels, and time below range at <70 and 54 mg/dL across different kidney function categories.
Results:
In patients with chronic kidney disease (CKD) stages 1–2 (n=934), 89.3% who had a random plasma C-peptide level higher than 600 pmol/L exhibited a CV of ≤36%. Among those in CKD stage 3 (n=161) with a random plasma C-peptide level exceeding 600 pmol/L, 66.7% showed a CV of ≤36%. In stages 4–5 of CKD (n=90), the correlation between random C-peptide levels and CV was not significant (r=–0.05, P=0.640), including cases with a CV greater than 36% despite very high random plasma C-peptide levels. Random plasma C-peptide levels and CGM-assessed CV significantly predicted hypoglycemia in CKD stages 1–2 and 1–5, respectively.
Conclusion
The established C-peptide criteria in Western populations are applicable to Korean people with diabetes for hypoglycemic risk prediction, unless kidney function is impaired equivalent to CKD stage 3–5. The CGM-defined CV is informative for hypoglycemic risk prediction regardless of kidney function.
6.Quercetin-3-Methyl Ether Induces Early Apoptosis to Overcome HRV1B Immune Evasion, Suppress Viral Replication, and Mitigate Inflammatory Pathogenesis
Jae-Hyoung SONG ; Seo-Hyeon MUN ; Sunil MISHRA ; Seong-Ryeol KIM ; Heejung YANG ; Sun Shim CHOI ; Min-Jung KIM ; Dong-Yeop KIM ; Sungchan CHO ; Youngwook HAM ; Hwa-Jung CHOI ; Won-Jin BAEK ; Yong Soo KWON ; Jae-Hoon CHANG ; Hyun-Jeong KO
Biomolecules & Therapeutics 2025;33(2):388-398
Human rhinovirus (HRV) causes the common cold and exacerbates chronic respiratory diseases, such as asthma and chronic obstructive pulmonary disease. Despite its significant impact on public health, there are currently no approved vaccines or antiviral treatments for HRV infection. Apoptosis is the process through which cells eliminate themselves through the systematic activation of intrinsic death pathways in response to various stimuli. It plays an important role in viral infections and serves as a key immune defense mechanism in the interactions between viruses and the host. In the present study, we investigated the antiviral effects of quercetin-3-methyl ether, a flavonoid isolated from Serratula coronata, on human rhinovirus 1B (HRV1B). Quercetin-3-methyl ether significantly inhibited HRV1B replication in HeLa cells in a concentration-dependent manner, thereby reducing cytopathic effects and viral RNA levels. Time-course and time-of-addition analyses confirmed that quercetin-3-methyl ether exhibited antiviral activity during the early stages of viral infection, potentially targeting the replication and translation phases. Gene expression analysis using microarrays revealed that pro-apoptotic genes were upregulated in quercetin-3-methyl ether-treated cells, suggesting that quercetin-3-methyl ether enhances early apoptosis to counteract HRV1B-induced immune evasion. In vivo administration of quercetin-3-methyl ether to HRV1B-infected mice significantly reduced viral RNA levels and inflammatory cytokine production in the lung tissues. Our findings demonstrated the potential of quercetin-3-methyl ether as a novel antiviral agent against HRV1B, thereby providing a promising therapeutic strategy for the management of HRV1B infections and related complications.
7.Plasma C-Peptide Levels and the Continuous Glucose Monitoring-Defined Coefficient of Variation in Risk Prediction for Hypoglycemia in Korean People with Diabetes Having Normal and Impaired Kidney Function
So Yoon KWON ; Jiyun PARK ; So Hee PARK ; You-Bin LEE ; Gyuri KIM ; Kyu Yeon HUR ; Jae Hyeon KIM ; Sang-Man JIN
Endocrinology and Metabolism 2025;40(2):268-277
Background:
We aimed to investigate the predictive values of plasma C-peptide levels and the continuous glucose monitoring (CGM)-defined coefficient of variation (CV) in risk prediction for hypoglycemia in Korean people with diabetes with normal and impaired kidney function.
Methods:
We analyzed data from 1,185 participants diagnosed with type 1 and type 2 diabetes who underwent blinded professional CGM between January 2009 and May 2021 at outpatient clinics. We explored correlations among CGM-defined CV, plasma C-peptide levels, and time below range at <70 and 54 mg/dL across different kidney function categories.
Results:
In patients with chronic kidney disease (CKD) stages 1–2 (n=934), 89.3% who had a random plasma C-peptide level higher than 600 pmol/L exhibited a CV of ≤36%. Among those in CKD stage 3 (n=161) with a random plasma C-peptide level exceeding 600 pmol/L, 66.7% showed a CV of ≤36%. In stages 4–5 of CKD (n=90), the correlation between random C-peptide levels and CV was not significant (r=–0.05, P=0.640), including cases with a CV greater than 36% despite very high random plasma C-peptide levels. Random plasma C-peptide levels and CGM-assessed CV significantly predicted hypoglycemia in CKD stages 1–2 and 1–5, respectively.
Conclusion
The established C-peptide criteria in Western populations are applicable to Korean people with diabetes for hypoglycemic risk prediction, unless kidney function is impaired equivalent to CKD stage 3–5. The CGM-defined CV is informative for hypoglycemic risk prediction regardless of kidney function.
8.Catalpa bignonioides extract improves exercise performance through regulation of growth and metabolism in skeletal muscles
Hoibin Jeong ; Dong-joo Lee ; Sung-Pil Kwon ; SeonJu Park ; Song-Rae Kim ; Seung Hyun Kim ; Jae-Il Park ; Deug-chan Lee ; Kyung-Min Choi ; WonWoo Lee ; Ji-Won Park ; Bohyun Yun ; Su-Hyeon Cho ; Kil-Nam Kim
Asian Pacific Journal of Tropical Biomedicine 2024;14(2):47-54
Objective: To evaluate the effects of Catalpa bignonioides fruit extract on the promotion of muscle growth and muscular capacity in vitro and in vivo. Methods: Cell viability was measured using the 3-(4,5-dimethylthiazol- 2-yl)-2,5-diphenyltetrazolium bromide assay. Cell proliferation was assessed using a 5-bromo-2’-deoxyuridine (BrdU) assay kit. Western blot analysis was performed to determine the protein expressions of related factors. The effects of Catalpa bignonioides extract were investigated in mice using the treadmill exhaustion test and whole-limb grip strength assay. Chemical composition analysis was performed using high-performance liquid chromatography (HPLC). Results: Catalpa bignonioides extract increased the proliferation of C2C12 mouse myoblasts by activating the Akt/mTOR signaling pathway. It also induced metabolic changes, increasing the number of mitochondria and glucose metabolism by phosphorylating adenosine monophosphate-activated protein kinase. In an in vivo study, the extract-treated mice showed improved motor abilities, such as muscular endurance and grip strength. Additionally, HPLC analysis showed that vanillic acid may be the main component of the Catalpa bignonioides extract that enhanced muscle strength. Conclusions: Catalpa bignonioides improves exercise performance through regulation of growth and metabolism in skeletal muscles, suggesting its potential as an effective natural agent for improving muscular strength.
9.Comparative Analysis of Liquid Chromatography-Tandem Mass Spectrometry and Radioimmunoassay in Determining Plasma Aldosterone Concentration and Plasma Renin Activity for Primary Aldosteronism Screening
So Yoon KWON ; Kyeong-Jin KIM ; Soo-Youn LEE ; Jae Hyeon KIM
Endocrinology and Metabolism 2024;39(6):965-969
Liquid chromatography-tandem mass spectrometry (LC-MS/MS) accurately measures plasma aldosterone concentration (PAC), but its correlation with radioimmunoassay (RIA), equivalent RIA levels, and optimal cutoff for PAC and aldosterone-to-renin ratio (ARR) in primary aldosteronism (PA) screening have not been determined in a Korean population. Our study of 127 patients who underwent diagnostic testing for PA showed that the LC-MS/MS and RIA methods have good correlation, with a mean bias of 29.3% for PAC. An LC-MS/MS PAC level of 11.7 ng/dL was equivalent to an RIA PAC level of 15 ng/dL. Receiver operating characteristic curve analysis showed that an LC-MS/MS PAC level of 10.3 ng/dL and LC-MS/MS ARR level of 20.0 provided sensitivity of 73.1% with a specificity of 57.3% and sensitivity of 92.3% with a specificity of 14.7%, respectively. When the LC-MS/MS method is used for PA screening, an adjustment of cutoff values is necessary.
10.Perioperative nutritional practice of surgeons in Korea: a survey study
Ji-Hyeon PARK ; Mi Ran JUNG ; Sang Hyun KIM ; Hongbeom KIM ; Gyeongsil LEE ; Jae-Seok MIN ; Heung-Kwon OH ; Jung Hoon BAE ; Yoona CHUNG ; Dong-Seok HAN ; Seung Wan RYU ;
Annals of Clinical Nutrition and Metabolism 2024;16(3):134-148
Purpose:
Enhanced recovery after surgery (ERAS) protocols advocate reduced fasting and early nutrition to improve recovery in surgical patients. However, data on ERAS implementation among Korean surgeons performing major abdominal surgeries remain sparse.
Methods:
A survey conducted by the External Relation Committee of the Korean Society of Surgical Metabolism and Nutrition assessed perioperative nutritional practices among 389 Korean general surgeons from February to September 2023. The survey covered preoperative fasting, carbohydrate drinks, nasogastric tube use, postoperative dietary progression, parenteral nutrition (PN), and oral supplements, yielding 551 responses stratified by specialty.
Results:
More than 80% of respondents practiced “midnight NPO (Nil Per Os)” fasting, often at the anesthesiology department’s request, while 70%–80% reported no use of preoperative carbohydrate drinks. Most surgeons began dietary progression with water on postoperative day one, advancing to a liquid or soft diet by day two. PN was routinely prescribed by 49% of respondents, with a common dosage of 1,000–1,500 kcal/d. Oral supplements were selectively provided, with 21% of surgeons prescribing them universally.
Conclusion
The results reveal significant variability in perioperative nutrition practices across Korean surgical specialties, with many adhering to traditional practices despite ERAS guidelines. These findings highlight a need for standardized guidelines in Korea to optimize perioperative nutritional support and improve patient recovery outcomes following major abdominal surgeries.

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