Objectives: Gastric cancer (GC) demonstrates a sex disparity that may also be associated with body mass index (BMI). This study explored whether the effect of BMI on the risk of GC varies by sex. Methods: The study cohort included 341,999 Koreans aged 40 years or older from the National Health Insurance Service–Health Screening Cohort, with a median follow-up period of 10 years. Participants were categorized into five groups based on their BMI. The effect of BMI was evaluated using Cox proportional hazard regression. Additionally, stratification analysis was performed according to waist circumference. Results: An increased risk of developing GC was observed across the study population among those with obesity (BMI 25.0–29.9 kg/m2 ; hazard ratio [HR], 1.11; 95% CI , 1.03–1.20) and severe obesity (BMI ≥30.0 kg/m2 ; HR, 1.22; 95% CI, 1.01–1.47), considering a 2-year latency period. Notably, the rise in GC risk was particularly pronounced among women with obesity and men with severe obesity. In the age-stratified analysis, severe obesity (BMI ≥30.0 kg/m2 ) was associated with an increased risk of GC in men under 50 years old (HR, 1.83; 95% CI, 0.99–3.37). For individuals aged ≥50 years, obesity was linked to a heightened risk of GC in both sexes. Furthermore, normal BMI (18.5–22.9 kg/m2 ) was associated with an increased GC risk in women. Conclusion These findings indicate a positive association between excess body weight and the risk of GC in Koreans, particularly among men with severe obesity.

Colorectal cancer (CRC) is one of the most common causes of cancer morbidity in both sexes but shows sex differences.First, sex-specific differences in tumor recurrence and survival rates have been reported. For example, the development of CRC is found about 1.5 times higher and 4–8 years earlier in males compared to females, suggesting the protective role of estrogen in the disease. Furthermore, female patients have a higher risk of developing right-sided (proximal) colon cancer than male patients, which is known to have more aggressive clinical character compared to left-sided (distal) colon cancer. That is, left and right CRCs show differences in carcinogenic mechanism, that the chromosomal instability pathway is more common in left colon cancer while the microsatellite instability and serrated pathways are more common in right colon cancer.It is thought that there are sex-based differences on the background of carcinogenesis of CRC. Sex differences of CRC have two aspects, sexual dimorphism (biological differences in hormones and genes) and gender differences (non-biological differences in societal attitudes and behavior). Recently, sex difference of colon adenoma pathway and sexual dimorphism in the biology of gene and protein expression, and in endocrine cellular signaling in the CRC carcinogenesis have been accumulated. In addition, behavioral patterns can lead to differences in exposure to risk factors such as drinking or smoking, diet and physical activity. Therefore, understanding sex/gender-related biological and sociocultural differences in CRC risk will help in providing strategies for screening, treatment and prevention protocols to reduce the mortality and improve the quality of life.In this review, sex/gender differences in colon adenoma pathway and various aspects such as clinicopathological, biological, molecular, and socio-cultural aspects of CRC were described.

No abstract available.
Esophagus*

BACKGROUND/AIMS: Despite numerous studies on the relation of genetic polymorphisms with irritable bowel syndrome (IBS), the results still remain inconclusive. The aim of this study was to assess the possible association between SLC6A4 serotonin transporter gene linked polymorphic region (5-HTTLPR), ADRA2A -1291C>G, GNB3 825C>T, CCK1R intron 779T>C and TRPV1 945G>C polymorphisms and IBS based on Rome III criteria in Korea. METHODS: Study subjects were prospectively recruited from visitors to Seoul National University Bundang Hospital between July 2009 and January 2014. Ninety-nine IBS patients and 171 healthy controls were enrolled. Polymorphisms of above-mentioned 5 genes were genotyped. Serum serotonin from 101 participants was measured by ELISA and compared according to SLC6A4 5-HTTLPR polymorphisms and IBS subtypes. RESULTS: Regarding SLC6A4 5-HTTLPR polymorphism, L/L genotype was significantly associated with the total IBS, constipation predominant IBS (IBS-C) and mixture of diarrhea and constipation IBS (IBS-M) (adjusted OR: 4.35, 95% CI: 1.04-16.67; adjusted OR: 11.11, 95% CI: 1.69-50.00 and adjusted OR: 5.56, 95% CI: 1.05-33.33, respectively). Carrying ADRA2A -1291G allele was significantly associated with total IBS and diarrhea predominant IBS (adjusted OR: 3.37, 95% CI: 1.16-9.77 and adjusted OR: 5.64, 95% CI: 1.18-27.01, respectively). IBS-C patients showed reduced level of serum serotonin compared to controls and patients with diarrhea predominant IBS (50.2 ng/mL vs. 69.0 ng/mL and 92.9 ng/mL, P = 0.017 and P = 0.001, respectively). CONCLUSIONS: Genetic polymorphisms of SLC6A4 5-HTTLPR and ADRA2A -1291C>G could be one of the pathophysiological factors of IBS in Korea. Reduced serum serotonin shown in the IBS-C group suggested a role of serotonin in IBS, but large study is needed for confirming genotypic difference in serum serotonin level.
Alleles ; Constipation ; Diarrhea ; Enzyme-Linked Immunosorbent Assay ; Genotype ; Humans ; Introns ; Irritable Bowel Syndrome* ; Korea ; Polymorphism, Genetic ; Polymorphism, Single Nucleotide ; Prospective Studies ; Receptors, Adrenergic ; Seoul ; Serotonin ; Serotonin Plasma Membrane Transport Proteins*

Purpose: The 2020 Dietary Reference Intakes for Koreans (KDRIs) serves as a foundation for daily nutrient and energy recommendations aiming to enhance public health and prevent chronic diseases. They act as guidelines for maintaining proper nutrition and overall health.Using KDRIs is crucial for promoting healthier lifestyles and making informed dietary choices. Thus, this study explores the influence of a nutrition education program, based on the 2020 KDRIs, on the nutrition knowledge and dietary habits of undergraduates in Gyeongsangnam-do and Gyeonggi-do. Methods: The nutrition education program, designed with diverse instructional materials, was executed across a wide range of universities. The education group (n = 75) engaged in the program for a 6-week instructional period, while the control group (n = 53) underwent the survey without participating in the education program. Nutrition Quotient (NQ) and knowledge assessments were administered to both groups immediately before and after the instructional period. Results: Within the education group, the nutrition education program positively impacted responses to NQ practice items, including knowledge of nutrition, daily intake, and portion sizes (p < 0.05). In contrast, there were no significant differences between the before and after responses of the control group for most survey items. Post-program evaluations showed significantly higher self-assessment scores and increased satisfaction levels (p < 0.05), with the satisfaction rate for the education program using the 2020 KDRIs reaching 99.2%. Conclusion This study has demonstrated the positive impact of an effective nutrition education program. However, there is a need for the continuous development and implementation of nutrition education programs to sustain these outcomes and further enhance the nutritional education experience.

Gastric cancer is associated with high morbidity and mortality rates worldwide. Identifying individuals at high risk is important for surveillance and prevention of gastric cancer. Having first-degree relatives diagnosed with gastric cancer is a strong and consistent risk factor for gastric cancer, but the pathogenic mechanisms behind this familial aggregation are unclear. Against this background, we reviewed the risk factors for gastric cancer in those with a first-degree relative with gastric cancer, and the possible causes for familial clustering of gastric cancer including bacterial factors, inherited genetic susceptibility, environmental factors or a combination thereof. Among individuals with a family history, current or past Helicobacter pylori infection, having two or more first-degree affected relatives or female gender was associated with an increased risk of developing gastric cancer. To date, no specific single nucleotide polymorphism has been shown to be associated with familial clustering of gastric cancer. H. pylori eradication is the most important strategy for preventing gastric cancer in first-degree relatives of gastric cancer patients, particularly those in their 20s and 30s. Early H. pylori eradication could prevent the progression to intestinal metaplasia and reduce the synergistic effect on gastric carcinogenesis in individuals with both H. pylori infection and a family history. Endoscopic surveillance is also expected to benefit individuals with a family history. Further large-scale, prospective studies are warranted to evaluate the cost-effectiveness and optimal time point for endoscopy in this population. Moreover, genome-wide association studies that incorporate environmental and dietary factors on a ‘big data’ basis will increase our understanding of the pathogenesis of gastric cancer.
Carcinogenesis ; Endoscopy ; Female ; Genetic Predisposition to Disease ; Genome-Wide Association Study ; Helicobacter pylori ; Humans ; Metaplasia ; Mortality ; Polymorphism, Single Nucleotide ; Prospective Studies ; Risk Factors ; Stomach Neoplasms*

BACKGROUND: Prostatitis, one of the most common diseases of the prostate, is a complex disease with various clinical features. This study aims to analyze the utilization and prescribing patterns of antibiotics in Korean patients with prostatitis between 2008 and 2015. METHODS: We used the National Health Insurance Database complied from the Health Insurance Review and Assessment Service (HIRA). The outcomes included the number of claims, number of patients, medical cost, and length of stay for each year. In addition, the prescribing patterns of antibiotics, including fluoroquinolone, and low-dose use of ciprofloxacin and levofloxacin were investigated. RESULTS: The total number of patients and medical cost increased by 9.5% and 51.7% from 2008 to 2015, respectively. Most prostatitis patients were classified as chronic prostatitis patients. The prescribing proportion of antibiotics for chronic prostatitis outpatients decreased from 71.0% to 66.9% from 2008 to 2015, and fluoroquinolone accounted for more than half of the total antibiotics. Over 80% of prescription of levofloxacin and ciprofloxacin was identified to be for low-dose use. CONCLUSION: Most of the patients with prostatitis experienced pain relief and condition improvement after antibiotic treatment; however, chronic prostatitis and chronic pelvic pain syndrome recur easily. Therefore, active disease management and further studies are needed to enhance our understanding of effective treatment for prostatitis.
Anti-Bacterial Agents* ; Ciprofloxacin ; Disease Management ; Humans ; Insurance, Health ; Korea* ; Length of Stay ; Levofloxacin ; National Health Programs ; Outpatients ; Pelvic Pain ; Prescriptions ; Prostate ; Prostatitis*

Purpose: 17β-Estradiol (E2) supplementation suppresses MC38 tumor growth by downregulating the expression of programmed death-ligand 1 (PD-L1). This study aims to figure out the gut microbiota that respond to anti–PD-L1 and/or estrogen treatment in MC38 colon cancer model. Materials and Methods: A syngeneic colon tumor model was developed by injection of MC38 cells into C57BL/6 background male and female mice. Three days before MC38 cells injection, E2 was supplemented to male mice daily for 1 week. Male and female mice with MC38 tumors (50-100 mm3) were injected with anti–PD-L1 antibody. Fresh feces were collected 26 days after injection of MC38 cells and 16S rRNA metagenomics sequencing of DNA extracted from feces was used to assess gut microbial composition. Results: At the taxonomic family level, Muribaculaceae was enriched only in the MC38 male control group. In male mice, linear discriminant analysis effect size analysis at the species level revealed that the four microorganisms were commonly regulated in single and combination treatment with anti–PD-L1 and/or E2; a decrease in PAC001068_g_uc and PAC001070_s (family Muribaculaceae) and increase in PAC001716_s and PAC001785_s (family Ruminococcaceae). Interestingly, in the anti–PD-L1 plus E2 group, a decrease in opportunistic pathogens (Enterobacteriaceae group) and an increase in commensal bacteria (Lactobacillus murinus group and Parabacteroides goldsteinii) were observed. Furthermore, the abundance of Parabacteroides goldsteinii was increased in both males and females in the anti–PD-L1 group. Conclusion Our results suggest that gut microbial changes induced by the pretreatment of estrogen before anti–PD-L1 might contribute to treatment of MC38 colon cancer.

Background/Aims: A high-fat diet (HFD) causes dysbiosis and promotes inflammatory responses in the colon. This study aims to evaluate the effects of Clostridium butyricum on HFD-induced gut microbial changes in rats. Methods: Six-week-old Fischer-344 rats with both sexes were given a control or HFD during 8 weeks, and 1-to-100-fold diluted Clostridium butyricum were administered by gavage. Fecal microbiota analyses were conducted using 16S ribosomal RNA metagenomic sequencing and predictive functional profiling of microbial communities in metabolism. Results: A significant increase in Ruminococcaceae and Lachnospiraceae, which are butyric acid-producing bacterial families, was observed in the probiotics groups depending on sex. In contrast, Akkermansia muciniphila, which increased through a HFD regardless of sex, and decreased in the probiotics groups. A. muciniphila positively correlated with Claudin-1 expression in males (P < 0.001) and negatively correlated with the expression of Claudin-2 (P = 0.042), IL-1β (P = 0.037), and IL-6 (P = 0.044) in females. In terms of functional analyses, a HFD decreased the relative abundances of M00131 (carbohydrate metabolism module), M00579, and M00608 (energy metabolism), and increased those of M00307 (carbohydrate metabolism), regardless of sex. However, these changes recovered especially in male C. butyricum groups. Furthermore, M00131, M00579, and M00608 showed a positive correlation and M00307 showed a negative correlation with the relative abundance of A. muciniphila (P < 0.001). Conclusion The beneficial effects of C. butyricum on HFD-induced gut dysbiosis in young male rats originate from the functional profiles of carbohydrate and energy metabolism.

PURPOSE: We examined the respiratory morbidities in late-preterm infants compared to those of the early-preterm infants and term infants throughout the first year of life. METHODS: Data were retrospectively collected for 87 late-preterm, 72 early-preterm, and 608 term infants who were admitted to NICU and the nursery of Busan St. Mary's Medical Center from Jan 2007 to Oct 2009. RESULTS: There were significant differences in the proportions of the out-born infants, twin pregnancy, small for gestational age, and Caesarean section in the three groups (P<0.05). Late-preterm and early-preterm infants had longer duration of hospitalization, larger proportions of respiratory distress syndrome, mechanical ventilation at birth, oxygen therapy after 48 hours of birth, oxygen dependency at 28 days, and continuous positive airway pressure support at 28 days compared to term infants during the neonatal period (P=0.000). Late-preterm infants and early-preterm infants were re-admitted more often than term infants during the first year of life (P=0.000). Also Late-preterm and early-preterm infants had increased chance of respiratory tract illness than term infants (P=0.001). CONCLUSION: In this study, we demonstrated that there are higher chances of respiratory morbidities in the late-preterm infants than the term infants either during the neonatal period or throughout the first year of life, although early-preterm infants showed greatest respiratory morbidities.
Cesarean Section ; Continuous Positive Airway Pressure ; Dependency (Psychology) ; Female ; Gestational Age ; Hospitalization ; Humans ; Infant ; Nurseries ; Oxygen ; Parturition ; Pregnancy ; Pregnancy, Twin ; Respiration, Artificial ; Respiratory System ; Retrospective Studies