This study aimed to establish an organoid culture model using small intestine tissues from male and female C57BL/6 mice and to compare it with rat organoid cultures derived from frozen tissues. Crypts were isolated from the small intestines of eight-week-old male and female mice and cultured in 3D extracellular matrix with Wnt, R-spondin, and Noggin. In addition, small intestine tissues from sixteen-week-old F344 rats were preserved in a storage solution immediately post-sacrifice and stored at –80°C before being transferred to a nitrogen tank. Upon thawing, crypts from frozen rat tissues failed to develop into organoids due to structural damage, suggesting the need for fresh tissues or optimized preservation methods. In contrast, mouse-derived organoids showed viability for 7 days, with distinct morphological changes and clear differentiation by Day 7. Quantitative real-time PCR analysis revealed that Lgr5, a stem cell marker, showed significantly higher expression in organoids than in tissues, confirming the successful establishment of the organoid culture. Among epithelial markers, the antimicrobial enzyme Lyz1 was more highly expressed in organoids, while Muc2, a key goblet cell marker, was more highly expressed in male tissues. The enterocyte marker Alp exhibited higher expression in male organoids compared to females, with no sex differences in tissues. These findings highlight sex-specific differences in gene expression related to small intestine differentiation and demonstrate the challenges in organoid culture from frozen rat tissues. The results suggest the importance of immediate tissue processing or improved preservation methods for successful organoid cultures.

Purpose: Physical activity (PA) is considered a potentially effective factor in the primary prevention of gastric cancer (GC). As body mass index (BMI) and waist circumference (WC) differ by sex, particularly with age, this study aimed to investigate the impact of PA on GC development, considering BMI and WC variations by sex. Materials and Methods: We analyzed the impact of PA on GC development using Cox proportional hazard regression in a cohort of 314,525 Korean individuals from the National Health Insurance Service–Health Screening database, using data from 2009–2019.Additionally, subgroup analyses were conducted based on BMI and WC. The models were adjusted for age, sex, smoking status, alcohol consumption, BMI, and comorbidities. Results: The effect of PA on the prevention of GC development was relatively evident in males. The high PA group (metabolic equivalents of task, METs/week of 500–999) showed a lower risk of GC compared to the group with METs/week of 0 (hazard ratio [HR], 0.88; 95% confidence interval [CI], 0.79–0.98). Especially in males with WC <90 cm and BMI <23 kg/m2 , a lower risk of GC was observed in the group with METs/week of 1–499 compared to the group with METs/week of 0 (HR, 0.80; 95% CI, 0.67–0.96). In contrast, no consistent association was observed between PA levels and risk of GC in females. Conclusions Moderate PA had a preventive effect on GC development in males, particularly in those with low BMI and WC. However, this effect was not observed in females.

This study aimed to establish an organoid culture model using small intestine tissues from male and female C57BL/6 mice and to compare it with rat organoid cultures derived from frozen tissues. Crypts were isolated from the small intestines of eight-week-old male and female mice and cultured in 3D extracellular matrix with Wnt, R-spondin, and Noggin. In addition, small intestine tissues from sixteen-week-old F344 rats were preserved in a storage solution immediately post-sacrifice and stored at –80°C before being transferred to a nitrogen tank. Upon thawing, crypts from frozen rat tissues failed to develop into organoids due to structural damage, suggesting the need for fresh tissues or optimized preservation methods. In contrast, mouse-derived organoids showed viability for 7 days, with distinct morphological changes and clear differentiation by Day 7. Quantitative real-time PCR analysis revealed that Lgr5, a stem cell marker, showed significantly higher expression in organoids than in tissues, confirming the successful establishment of the organoid culture. Among epithelial markers, the antimicrobial enzyme Lyz1 was more highly expressed in organoids, while Muc2, a key goblet cell marker, was more highly expressed in male tissues. The enterocyte marker Alp exhibited higher expression in male organoids compared to females, with no sex differences in tissues. These findings highlight sex-specific differences in gene expression related to small intestine differentiation and demonstrate the challenges in organoid culture from frozen rat tissues. The results suggest the importance of immediate tissue processing or improved preservation methods for successful organoid cultures.

Purpose: Physical activity (PA) is considered a potentially effective factor in the primary prevention of gastric cancer (GC). As body mass index (BMI) and waist circumference (WC) differ by sex, particularly with age, this study aimed to investigate the impact of PA on GC development, considering BMI and WC variations by sex. Materials and Methods: We analyzed the impact of PA on GC development using Cox proportional hazard regression in a cohort of 314,525 Korean individuals from the National Health Insurance Service–Health Screening database, using data from 2009–2019.Additionally, subgroup analyses were conducted based on BMI and WC. The models were adjusted for age, sex, smoking status, alcohol consumption, BMI, and comorbidities. Results: The effect of PA on the prevention of GC development was relatively evident in males. The high PA group (metabolic equivalents of task, METs/week of 500–999) showed a lower risk of GC compared to the group with METs/week of 0 (hazard ratio [HR], 0.88; 95% confidence interval [CI], 0.79–0.98). Especially in males with WC <90 cm and BMI <23 kg/m2 , a lower risk of GC was observed in the group with METs/week of 1–499 compared to the group with METs/week of 0 (HR, 0.80; 95% CI, 0.67–0.96). In contrast, no consistent association was observed between PA levels and risk of GC in females. Conclusions Moderate PA had a preventive effect on GC development in males, particularly in those with low BMI and WC. However, this effect was not observed in females.

This study aimed to establish an organoid culture model using small intestine tissues from male and female C57BL/6 mice and to compare it with rat organoid cultures derived from frozen tissues. Crypts were isolated from the small intestines of eight-week-old male and female mice and cultured in 3D extracellular matrix with Wnt, R-spondin, and Noggin. In addition, small intestine tissues from sixteen-week-old F344 rats were preserved in a storage solution immediately post-sacrifice and stored at –80°C before being transferred to a nitrogen tank. Upon thawing, crypts from frozen rat tissues failed to develop into organoids due to structural damage, suggesting the need for fresh tissues or optimized preservation methods. In contrast, mouse-derived organoids showed viability for 7 days, with distinct morphological changes and clear differentiation by Day 7. Quantitative real-time PCR analysis revealed that Lgr5, a stem cell marker, showed significantly higher expression in organoids than in tissues, confirming the successful establishment of the organoid culture. Among epithelial markers, the antimicrobial enzyme Lyz1 was more highly expressed in organoids, while Muc2, a key goblet cell marker, was more highly expressed in male tissues. The enterocyte marker Alp exhibited higher expression in male organoids compared to females, with no sex differences in tissues. These findings highlight sex-specific differences in gene expression related to small intestine differentiation and demonstrate the challenges in organoid culture from frozen rat tissues. The results suggest the importance of immediate tissue processing or improved preservation methods for successful organoid cultures.

Purpose: Physical activity (PA) is considered a potentially effective factor in the primary prevention of gastric cancer (GC). As body mass index (BMI) and waist circumference (WC) differ by sex, particularly with age, this study aimed to investigate the impact of PA on GC development, considering BMI and WC variations by sex. Materials and Methods: We analyzed the impact of PA on GC development using Cox proportional hazard regression in a cohort of 314,525 Korean individuals from the National Health Insurance Service–Health Screening database, using data from 2009–2019.Additionally, subgroup analyses were conducted based on BMI and WC. The models were adjusted for age, sex, smoking status, alcohol consumption, BMI, and comorbidities. Results: The effect of PA on the prevention of GC development was relatively evident in males. The high PA group (metabolic equivalents of task, METs/week of 500–999) showed a lower risk of GC compared to the group with METs/week of 0 (hazard ratio [HR], 0.88; 95% confidence interval [CI], 0.79–0.98). Especially in males with WC <90 cm and BMI <23 kg/m2 , a lower risk of GC was observed in the group with METs/week of 1–499 compared to the group with METs/week of 0 (HR, 0.80; 95% CI, 0.67–0.96). In contrast, no consistent association was observed between PA levels and risk of GC in females. Conclusions Moderate PA had a preventive effect on GC development in males, particularly in those with low BMI and WC. However, this effect was not observed in females.

Purpose: This study aimed to identify the association between coronavirus disease 2019 (COVID-19) transmission levels and undergoing glycated hemoglobin (HbA1c) test and complication screenings among patients with diabetes mellitus. Materials and Methods: We included a total of 3601 diabetes patients’ data from the 2020 Korean Community Health Survey to analyze the extent of the HbA1c testing and fundus examination, and 3592 diabetes patients’ data to analyze kidney disease screening. COVID-19 transmission levels were classified into low transmission (Busan, Gwangju, Daejeon, Ulsan, and Sejong) and high transmission (Daegu, where the first large outbreak of COVID-19 occurred in Korea). Multiple logistic regression was used to obtain adjusted odds ratio (ORs) and 95% confidence interval (CI) to determine the association of COVID-19 transmission levels with undergoing HbA1c testing and diabetes complication screening. Results: The proportion of subjects who underwent complication screening of diabetes was lower in the high transmission region (low transmission vs. high transmission: 42.3% vs. 38.0% for fundus examination; 48.9% vs. 45.7% for kidney disease screening). A high COVID-19 transmission level was associated with decreased odds of undergoing fundus examination (OR, 0.82; 95% CI, 0.69–0.98) and kidney disease screening (OR, 0.76; 95% CI, 0.63–0.91). However, COVID-19 transmission levels were not significantly associated with undergoing HbA1c testing. Conclusion A high level of COVID-19 transmission was associated with a decrease in undergoing fundus examination and kidney disease screening. To fully realize the potential benefit of diabetes complication screenings, further effort is required to identify and address challenges to obtaining these screenings, especially in outbreak regions.

In recent years, next-generation sequencing (NGS)–based genetic testing has become crucial in cancer care. While its primary objective is to identify actionable genetic alterations to guide treatment decisions, its scope has broadened to encompass aiding in pathological diagnosis and exploring resistance mechanisms. With the ongoing expansion in NGS application and reliance, a compelling necessity arises for expert consensus on its application in solid cancers. To address this demand, the forthcoming recommendations not only provide pragmatic guidance for the clinical use of NGS but also systematically classify actionable genes based on specific cancer types. Additionally, these recommendations will incorporate expert perspectives on crucial biomarkers, ensuring informed decisions regarding circulating tumor DNA panel testing.

OBJECTIVES: Unequal access to cancer clinical trials is an important issue, given the potential benefits of participation for cancer patients. We evaluated regional disparities in access to cancer clinical trials in Korea. METHODS: From the Ministry of Food and Drug Safety database, we extracted 2,465 records of all cancer clinical trials approved between January 2012 and April 2023. To measure disparities in cancer clinical trial access, we calculated the ratio of clinical trials open to non-capital areas relative to those open to capital areas. We then analyzed temporal trends in this ratio, which we termed the trial geographical equity index (TGEI). RESULTS: Disparities in access to cancer clinical trials, as indicated by the TGEI, did not significantly improve during the study period (regression coefficient, 0.002; p=0.59). However, for phase II/III trials sponsored by global pharmaceutical companies, the TGEI improved significantly (regression coefficient, 0.021; p<0.01). In contrast, the TGEI deteriorated for trials initiated by investigators or those testing domestically developed therapeutics (regression coefficient, -0.015; p=0.05). Furthermore, the increasing trend of TGEI for phase II/III trials sponsored by global companies began to reverse after 2019, coinciding with the outbreak of coronavirus disease 2019 (COVID-19). CONCLUSIONS Over the past decade, access to cancer clinical trials has improved in Korea, particularly for phase II/III trials evaluating therapeutics from global companies. However, this increase in accessibility has not extended to trials initiated by investigators or those assessing domestically developed therapeutics. Additionally, the impact of COVID-19 on disparities in clinical trial access should be closely monitored.

Background: Chronic cough is a common symptom encountered by healthcare practitioners.The global prevalence of chronic cough is 9.6%, with a female predominance. The aim of our study is to reveal the sex differences in prevalence and severity of chronic cough in South Korea, stratified by age and etiology. Methods: This study included adult patients with chronic cough who were recruited from 19 respiratory centers in South Korea. Patients completed the cough numeric rating scale (NRS) and COugh Assessment Test (COAT) questionnaire to assess the severity and multidimensional impact of cough. Results: Among the 625 patients, 419 (67.0%) were females, with a male-to-female ratio of 1:2.03. The mean age was 49.4 years, and the median duration of cough was 12 weeks. The mean NRS and COAT scores were 5.5 ± 1.8 and 9.5 ± 3.6, respectively. Female patients were older (45.3 ± 15.4 vs. 51.6 ± 15.2, P < 0.001) and more likely to have asthma/cough variant asthma (CVA) (26.7% vs. 40.8%, P = 0.001) than male patients. There was no difference in the duration or severity of cough between sexes, regardless of the cause. The male-tofemale ratio was lower for upper airway cough syndrome (UACS), asthma/CVA, and gastroesophageal reflux disease (GERD), but not for eosinophilic bronchitis (EB) or unexplained cough. The mean age of female patients was higher in UACS and asthma/CVA, but not in EB, GERD, or unexplained cough. The majority (24.2%) fell within the age category of 50s. The proportion of females with cough increased with age, with a significant rise in the 50s, 60s, and 70–89 age groups. The severity of cough decreased in the 50s, 60s, and 70–89 age groups, with no significant sex differences within the same age group. Conclusion The sex disparities in prevalence and severity of cough varied significantly depending on the age category and etiology. Understanding the specific sex-based difference could enhance comprehension of cough-related pathophysiology and treatment strategies.