Purpose: Feeding intolerance (FI) is a prevalent clinically sequential condition in preterm infants. To clarify its relationship with the gut microbiota, we compared microbial diversity and taxonomic composition at 2 and 4 weeks of age in infants born before 32 weeks of gestation. Methods: Between August 2021 and December 2022, we prospectively enrolled infants who delivered before 32 weeks of gestation and were admitted to the neonatal intensive care unit at CHA Bundang Medical Center. Forty-four preterm infants were grouped based on the presence (n=16) or absence (n=28) of FI. Fecal samples were obtained at 2 and 4 weeks after birth and analyzed using 16S rRNA gene sequencing to determine microbial profiles. Results: Microbial α-diversity and β-diversity did not differ significantly between groups at either time point. At the genus level, Staphylococcus was significantly more abundant in the FI group than in the feeding tolerance group at 2 weeks postnatal age (P=0.016). Linear discriminant analysis effect size revealed that Staphylococcus, Pseudomonas, and Escherichia were markedly enriched in the FI group at all time points. Conclusion Early colonization by potentially pathogenic genera, particularly Staphylococcus, may precede the development of FI in preterm infants. These findings highlight the potential microbial composition associated with FI and may provide preliminary insights for future microbiome-targeted research in neonatal care.

Background: Colorectal carcinomas (CRCs) with caudal-type homeobox 2 (CDX2) loss are recognized to pursue an aggressive behavior but tend to be accompanied by a high density of tumor-infiltrating lymphocytes (TILs). However, little is known about whether there is an interplay between CDX2 loss and TIL density in the survival of patients with CRC. Methods: Stage III CRC tissues were assessed for CDX2 loss using immunohistochemistry and analyzed for their densities of CD8 TILs in both intraepithelial (iTILs) and stromal areas using a machine learning-based analytic method. Results: CDX2 loss was significantly associated with a higher density of CD8 TILs in both intraepithelial and stromal areas. Both CDX2 loss and a high CD8 iTIL density were found to be prognostic parameters and showed hazard ratios of 2.314 (1.050–5.100) and 0.378 (0.175–0.817), respectively, for cancer-specific survival. A subset of CRCs with retained CDX2 expression and a high density of CD8 iTILs showed the best clinical outcome (hazard ratio of 0.138 [0.023–0.826]), whereas a subset with CDX2 loss and a high density of CD8 iTILs exhibited the worst clinical outcome (15.781 [3.939–63.230]). Conclusions Altogether, a high density of CD8 iTILs did not make a difference in the survival of patients with CRC with CDX2 loss. The combination of CDX2 expression and intraepithelial CD8 TIL density was an independent prognostic marker in adjuvant chemotherapy-treated patients with stage III CRC.

Purpose: Feeding intolerance (FI) is a prevalent clinically sequential condition in preterm infants. To clarify its relationship with the gut microbiota, we compared microbial diversity and taxonomic composition at 2 and 4 weeks of age in infants born before 32 weeks of gestation. Methods: Between August 2021 and December 2022, we prospectively enrolled infants who delivered before 32 weeks of gestation and were admitted to the neonatal intensive care unit at CHA Bundang Medical Center. Forty-four preterm infants were grouped based on the presence (n=16) or absence (n=28) of FI. Fecal samples were obtained at 2 and 4 weeks after birth and analyzed using 16S rRNA gene sequencing to determine microbial profiles. Results: Microbial α-diversity and β-diversity did not differ significantly between groups at either time point. At the genus level, Staphylococcus was significantly more abundant in the FI group than in the feeding tolerance group at 2 weeks postnatal age (P=0.016). Linear discriminant analysis effect size revealed that Staphylococcus, Pseudomonas, and Escherichia were markedly enriched in the FI group at all time points. Conclusion Early colonization by potentially pathogenic genera, particularly Staphylococcus, may precede the development of FI in preterm infants. These findings highlight the potential microbial composition associated with FI and may provide preliminary insights for future microbiome-targeted research in neonatal care.

Purpose: Feeding intolerance (FI) is a prevalent clinically sequential condition in preterm infants. To clarify its relationship with the gut microbiota, we compared microbial diversity and taxonomic composition at 2 and 4 weeks of age in infants born before 32 weeks of gestation. Methods: Between August 2021 and December 2022, we prospectively enrolled infants who delivered before 32 weeks of gestation and were admitted to the neonatal intensive care unit at CHA Bundang Medical Center. Forty-four preterm infants were grouped based on the presence (n=16) or absence (n=28) of FI. Fecal samples were obtained at 2 and 4 weeks after birth and analyzed using 16S rRNA gene sequencing to determine microbial profiles. Results: Microbial α-diversity and β-diversity did not differ significantly between groups at either time point. At the genus level, Staphylococcus was significantly more abundant in the FI group than in the feeding tolerance group at 2 weeks postnatal age (P=0.016). Linear discriminant analysis effect size revealed that Staphylococcus, Pseudomonas, and Escherichia were markedly enriched in the FI group at all time points. Conclusion Early colonization by potentially pathogenic genera, particularly Staphylococcus, may precede the development of FI in preterm infants. These findings highlight the potential microbial composition associated with FI and may provide preliminary insights for future microbiome-targeted research in neonatal care.

Background: An increased incidence of hair loss disorders has been noted among patients with coronavirus disease 2019 (COVID-19) and individuals vaccinated against COVID-19. However, research involving large populations on this topic is lacking. Objective: To investigate the risks associated with developing hair loss disorders in patients with COVID-19 and individuals vaccinated against COVID-19. Methods: This nationwide, population-based, cross-sectional study included patients diagnosed with COVID-19 and healthy individuals without a history of COVID-19 infection registered in the Korean National Health Insurance Service (NHIS) database between January 1, 2021, and December 31, 2021. COVID-19 infection and vaccine databases were integrated using this NHIS database. The odds ratios of hair loss disorders were compared using multivariate logistic regression models. Results: COVID-19 infection was associated with an increased risk of total alopecia (adjusted odds ratio [aOR], 1.076; 95% confidence interval [CI], 1.002–1.156), although this association was not significant after propensity score matching. No significant associations were found between COVID-19 infection and alopecia areata or telogen effluvium. However, COVID-19 vaccination was positively correlated with total alopecia (aOR, 1.266; 95% CI, 1.191–1.346), alopecia areata (aOR, 1.243; 95% CI, 1.154–1.339), and telogen effluvium (aOR, 1.495; 95% CI, 1.133–1.974). Conclusion COVID-19 vaccination was positively correlated with hair loss disorders but not COVID-19 infection. However, given the advantages of vaccines in reducing COVID-19 mortality and morbidity, alopecia may be relatively reversible and less severe. Physicians need to understand the benefits and possible side effects of the COVID-19 vaccine.

Background: MUTYH-associated polyposis is an autosomal recessive disorder associated with an increased lifetime risk of colorectal cancer and a moderately increased risk of ovarian, bladder, breast, and endometrial cancers. We analyzed the carrier frequency and estimated the incidence of MUTYH-associated polyposis in East Asian and Korean populations, for which limited data were previously available. Methods: We examined 125,748 exomes from the gnomAD database, including 9,197 East Asians, and additional data from 5,305 individuals in the Korean Variant Archive and 1,722 in the Korean Reference Genome Database. All MUTYH variants were interpreted according to the American College of Medical Genetics and Genomics and Association for Molecular Pathology guidelines and the Sequence Variant Interpretation guidelines from ClinGen. Results: The global carrier frequency of MUTYH-associated polyposis was 1.29%, with Europeans (non-Finnish) having the highest frequency of 1.86% and Ashkenazi Jews the lowest at 0.06%. East Asians and Koreans had a carrier frequency of 0.35% and 0.37% and an estimated incidence of 1 in 330,409 and 1 in 293,304 in Koreans, respectively, which were substantially lower than the global average of 1 in 24,160 and the European (nonFinnish) incidence of 1 in 11,520. Conclusions This was the first study to investigate the frequency of carriers of MUTYH-associated polyposis in East Asians, including specific subgroups, utilizing gnomAD and a Korean genome database. Our data provide valuable reference information for future investigations of MUTYH-associated polyposis to understand the genetic diversity and specific variants associated with this condition in East Asian populations.

Background: Shortage of organ donors in the Republic of Korea has become a major problem. To address this, it has been questioned whether heart transplant (HTx) allocation should be modified to reduce priority of older patients. We aimed to evaluate post-HTx outcomes according to recipient age and specific pre-HTx conditions using a nationwide prospective cohort. Methods: We analyzed clinical characteristics of 628 patients from the Korean Organ Transplant Registry who received HTx from January 2015 to December 2020. Enrolled recipients were divided into three groups according to age. We also included comorbidities including ambulatory status. Non-ambulatory status was defined as pre-HTx support with either extracorporeal membrane oxygenation, continuous renal replacement therapy, or mechanical ventilation. Results: Of the 628 patients, 195 were < 50 years, 322 were 50–64 years and 111 were ≥ 65years at transplant. Four hundred nine (65.1%) were ambulatory and 219 (34.9%) were nonambulatory. Older recipients tended to have more comorbidities, ischemic cardiomyopathy, and received older donors. Post-HTx survival was significantly lower in older recipients (P = 0.025) and recipients with non-ambulatory status (P < 0.001). However, in contrast to non-ambulatory recipients who showed significant survival differences according to the recipient’s age (P = 0.004), ambulatory recipients showed comparable outcomes (P = 0.465). Conclusion Our results do not support use of age alone as an allocation criterion. Transplant candidate age in combination with some comorbidities such as non-ambulatory status may identify patients at a sufficiently elevated risk at which suitability of HTx should be reconsidered.

Background: Shortage of organ donors in the Republic of Korea has become a major problem. To address this, it has been questioned whether heart transplant (HTx) allocation should be modified to reduce priority of older patients. We aimed to evaluate post-HTx outcomes according to recipient age and specific pre-HTx conditions using a nationwide prospective cohort. Methods: We analyzed clinical characteristics of 628 patients from the Korean Organ Transplant Registry who received HTx from January 2015 to December 2020. Enrolled recipients were divided into three groups according to age. We also included comorbidities including ambulatory status. Non-ambulatory status was defined as pre-HTx support with either extracorporeal membrane oxygenation, continuous renal replacement therapy, or mechanical ventilation. Results: Of the 628 patients, 195 were < 50 years, 322 were 50–64 years and 111 were ≥ 65years at transplant. Four hundred nine (65.1%) were ambulatory and 219 (34.9%) were nonambulatory. Older recipients tended to have more comorbidities, ischemic cardiomyopathy, and received older donors. Post-HTx survival was significantly lower in older recipients (P = 0.025) and recipients with non-ambulatory status (P < 0.001). However, in contrast to non-ambulatory recipients who showed significant survival differences according to the recipient’s age (P = 0.004), ambulatory recipients showed comparable outcomes (P = 0.465). Conclusion Our results do not support use of age alone as an allocation criterion. Transplant candidate age in combination with some comorbidities such as non-ambulatory status may identify patients at a sufficiently elevated risk at which suitability of HTx should be reconsidered.

Background: Shortage of organ donors in the Republic of Korea has become a major problem. To address this, it has been questioned whether heart transplant (HTx) allocation should be modified to reduce priority of older patients. We aimed to evaluate post-HTx outcomes according to recipient age and specific pre-HTx conditions using a nationwide prospective cohort. Methods: We analyzed clinical characteristics of 628 patients from the Korean Organ Transplant Registry who received HTx from January 2015 to December 2020. Enrolled recipients were divided into three groups according to age. We also included comorbidities including ambulatory status. Non-ambulatory status was defined as pre-HTx support with either extracorporeal membrane oxygenation, continuous renal replacement therapy, or mechanical ventilation. Results: Of the 628 patients, 195 were < 50 years, 322 were 50–64 years and 111 were ≥ 65years at transplant. Four hundred nine (65.1%) were ambulatory and 219 (34.9%) were nonambulatory. Older recipients tended to have more comorbidities, ischemic cardiomyopathy, and received older donors. Post-HTx survival was significantly lower in older recipients (P = 0.025) and recipients with non-ambulatory status (P < 0.001). However, in contrast to non-ambulatory recipients who showed significant survival differences according to the recipient’s age (P = 0.004), ambulatory recipients showed comparable outcomes (P = 0.465). Conclusion Our results do not support use of age alone as an allocation criterion. Transplant candidate age in combination with some comorbidities such as non-ambulatory status may identify patients at a sufficiently elevated risk at which suitability of HTx should be reconsidered.

Background: Colorectal carcinomas (CRCs) with caudal-type homeobox 2 (CDX2) loss are recognized to pursue an aggressive behavior but tend to be accompanied by a high density of tumor-infiltrating lymphocytes (TILs). However, little is known about whether there is an interplay between CDX2 loss and TIL density in the survival of patients with CRC. Methods: Stage III CRC tissues were assessed for CDX2 loss using immunohistochemistry and analyzed for their densities of CD8 TILs in both intraepithelial (iTILs) and stromal areas using a machine learning-based analytic method. Results: CDX2 loss was significantly associated with a higher density of CD8 TILs in both intraepithelial and stromal areas. Both CDX2 loss and a high CD8 iTIL density were found to be prognostic parameters and showed hazard ratios of 2.314 (1.050–5.100) and 0.378 (0.175–0.817), respectively, for cancer-specific survival. A subset of CRCs with retained CDX2 expression and a high density of CD8 iTILs showed the best clinical outcome (hazard ratio of 0.138 [0.023–0.826]), whereas a subset with CDX2 loss and a high density of CD8 iTILs exhibited the worst clinical outcome (15.781 [3.939–63.230]). Conclusions Altogether, a high density of CD8 iTILs did not make a difference in the survival of patients with CRC with CDX2 loss. The combination of CDX2 expression and intraepithelial CD8 TIL density was an independent prognostic marker in adjuvant chemotherapy-treated patients with stage III CRC.