Objective: We elucidated the effect of monochorionicity on neonatal and long-term neurologic outcomes on an individual basis in triplets. Methods: We retrospectively reviewed the perinatal outcomes and development and growth at 18 to 24 months corrected age (CA) of triplets born alive between 24 and 32 weeks of gestational age (GA) between 2009 and 2021 from the Seoul National University Hospital database. Neurod­evelopmental impairment (NDI) was defined as any delay among the Bayley-III domains (motor and language), cerebral palsy, hearing impairment, or visual loss and was performed at a CA of 18 to 24 months. Results: We included 40 sets of triplets (120 infants), comprising 26, 10, and 4 sets of trichorionic (TC), dichorionic (DC), and monochorionic (MC) triplets, respectively. Ten infants, unaffected by monochorionicity out of 30 DC infants, were included in the non-MC group. Eighty-eight infants were included in the non-MC group, and 32 infants were affected by monochorionicity. In vitro fertilization-embryo transfer was more frequent in the non-MC group (P<0.05), and twin-to-twin transfusion syndrome affected only the MC group (P<0.01). At 24 months of CA, a combined delay of language and cognition in Bayley-III was evident in the MC group (P<0.05). Although NDI did not significantly differ between the 2 groups (P=0.059), the composite outcome of NDI+ postnatal death was significantly different (P<0.05). NDI+ postnatal death correlated with GA, Z-score of birth weight, brain injury, and monochorionicity in the univariate analysis (P<0.05). Multivariate analysis revealed a significant correlation between monochorionicity and NDI+ postnatal death. (P<0.05). Conclusion Monochorionicity is associated with adverse long-term neurodevelopmental out comes.

Objective: We elucidated the effect of monochorionicity on neonatal and long-term neurologic outcomes on an individual basis in triplets. Methods: We retrospectively reviewed the perinatal outcomes and development and growth at 18 to 24 months corrected age (CA) of triplets born alive between 24 and 32 weeks of gestational age (GA) between 2009 and 2021 from the Seoul National University Hospital database. Neurod­evelopmental impairment (NDI) was defined as any delay among the Bayley-III domains (motor and language), cerebral palsy, hearing impairment, or visual loss and was performed at a CA of 18 to 24 months. Results: We included 40 sets of triplets (120 infants), comprising 26, 10, and 4 sets of trichorionic (TC), dichorionic (DC), and monochorionic (MC) triplets, respectively. Ten infants, unaffected by monochorionicity out of 30 DC infants, were included in the non-MC group. Eighty-eight infants were included in the non-MC group, and 32 infants were affected by monochorionicity. In vitro fertilization-embryo transfer was more frequent in the non-MC group (P<0.05), and twin-to-twin transfusion syndrome affected only the MC group (P<0.01). At 24 months of CA, a combined delay of language and cognition in Bayley-III was evident in the MC group (P<0.05). Although NDI did not significantly differ between the 2 groups (P=0.059), the composite outcome of NDI+ postnatal death was significantly different (P<0.05). NDI+ postnatal death correlated with GA, Z-score of birth weight, brain injury, and monochorionicity in the univariate analysis (P<0.05). Multivariate analysis revealed a significant correlation between monochorionicity and NDI+ postnatal death. (P<0.05). Conclusion Monochorionicity is associated with adverse long-term neurodevelopmental out comes.

Objective: We elucidated the effect of monochorionicity on neonatal and long-term neurologic outcomes on an individual basis in triplets. Methods: We retrospectively reviewed the perinatal outcomes and development and growth at 18 to 24 months corrected age (CA) of triplets born alive between 24 and 32 weeks of gestational age (GA) between 2009 and 2021 from the Seoul National University Hospital database. Neurod­evelopmental impairment (NDI) was defined as any delay among the Bayley-III domains (motor and language), cerebral palsy, hearing impairment, or visual loss and was performed at a CA of 18 to 24 months. Results: We included 40 sets of triplets (120 infants), comprising 26, 10, and 4 sets of trichorionic (TC), dichorionic (DC), and monochorionic (MC) triplets, respectively. Ten infants, unaffected by monochorionicity out of 30 DC infants, were included in the non-MC group. Eighty-eight infants were included in the non-MC group, and 32 infants were affected by monochorionicity. In vitro fertilization-embryo transfer was more frequent in the non-MC group (P<0.05), and twin-to-twin transfusion syndrome affected only the MC group (P<0.01). At 24 months of CA, a combined delay of language and cognition in Bayley-III was evident in the MC group (P<0.05). Although NDI did not significantly differ between the 2 groups (P=0.059), the composite outcome of NDI+ postnatal death was significantly different (P<0.05). NDI+ postnatal death correlated with GA, Z-score of birth weight, brain injury, and monochorionicity in the univariate analysis (P<0.05). Multivariate analysis revealed a significant correlation between monochorionicity and NDI+ postnatal death. (P<0.05). Conclusion Monochorionicity is associated with adverse long-term neurodevelopmental out comes.

Objective: We elucidated the effect of monochorionicity on neonatal and long-term neurologic outcomes on an individual basis in triplets. Methods: We retrospectively reviewed the perinatal outcomes and development and growth at 18 to 24 months corrected age (CA) of triplets born alive between 24 and 32 weeks of gestational age (GA) between 2009 and 2021 from the Seoul National University Hospital database. Neurod­evelopmental impairment (NDI) was defined as any delay among the Bayley-III domains (motor and language), cerebral palsy, hearing impairment, or visual loss and was performed at a CA of 18 to 24 months. Results: We included 40 sets of triplets (120 infants), comprising 26, 10, and 4 sets of trichorionic (TC), dichorionic (DC), and monochorionic (MC) triplets, respectively. Ten infants, unaffected by monochorionicity out of 30 DC infants, were included in the non-MC group. Eighty-eight infants were included in the non-MC group, and 32 infants were affected by monochorionicity. In vitro fertilization-embryo transfer was more frequent in the non-MC group (P<0.05), and twin-to-twin transfusion syndrome affected only the MC group (P<0.01). At 24 months of CA, a combined delay of language and cognition in Bayley-III was evident in the MC group (P<0.05). Although NDI did not significantly differ between the 2 groups (P=0.059), the composite outcome of NDI+ postnatal death was significantly different (P<0.05). NDI+ postnatal death correlated with GA, Z-score of birth weight, brain injury, and monochorionicity in the univariate analysis (P<0.05). Multivariate analysis revealed a significant correlation between monochorionicity and NDI+ postnatal death. (P<0.05). Conclusion Monochorionicity is associated with adverse long-term neurodevelopmental out comes.

Objective: We elucidated the effect of monochorionicity on neonatal and long-term neurologic outcomes on an individual basis in triplets. Methods: We retrospectively reviewed the perinatal outcomes and development and growth at 18 to 24 months corrected age (CA) of triplets born alive between 24 and 32 weeks of gestational age (GA) between 2009 and 2021 from the Seoul National University Hospital database. Neurod­evelopmental impairment (NDI) was defined as any delay among the Bayley-III domains (motor and language), cerebral palsy, hearing impairment, or visual loss and was performed at a CA of 18 to 24 months. Results: We included 40 sets of triplets (120 infants), comprising 26, 10, and 4 sets of trichorionic (TC), dichorionic (DC), and monochorionic (MC) triplets, respectively. Ten infants, unaffected by monochorionicity out of 30 DC infants, were included in the non-MC group. Eighty-eight infants were included in the non-MC group, and 32 infants were affected by monochorionicity. In vitro fertilization-embryo transfer was more frequent in the non-MC group (P<0.05), and twin-to-twin transfusion syndrome affected only the MC group (P<0.01). At 24 months of CA, a combined delay of language and cognition in Bayley-III was evident in the MC group (P<0.05). Although NDI did not significantly differ between the 2 groups (P=0.059), the composite outcome of NDI+ postnatal death was significantly different (P<0.05). NDI+ postnatal death correlated with GA, Z-score of birth weight, brain injury, and monochorionicity in the univariate analysis (P<0.05). Multivariate analysis revealed a significant correlation between monochorionicity and NDI+ postnatal death. (P<0.05). Conclusion Monochorionicity is associated with adverse long-term neurodevelopmental out comes.

Viral load and the duration of viral shedding of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) are important determinants of the transmission of coronavirus disease 2019.In this study, we examined the effects of viral doses on the lung and spleen of K18-hACE2 transgenic mice by temporal histological and transcriptional analyses. Approximately, 1×105 plaque-forming units (PFU) of SARS-CoV-2 induced strong host responses in the lungs from 2 days post inoculation (dpi) which did not recover until the mice died, whereas responses to the virus were obvious at 5 days, recovering to the basal state by 14 dpi at 1×102 PFU. Further, flow cytometry showed that number of CD8+ T cells continuously increased in 1×102 PFU-virusinfected lungs from 2 dpi, but not in 1×105 PFU-virus-infected lungs. In spleens, responses to the virus were prominent from 2 dpi, and number of B cells was significantly decreased at 1×105PFU; however, 1×102 PFU of virus induced very weak responses from 2 dpi which recovered by 10 dpi. Although the defense responses returned to normal and the mice survived, lung histology showed evidence of fibrosis, suggesting sequelae of SARS-CoV-2 infection. Our findings indicate that specific effectors of the immune response in the lung and spleen were either increased or depleted in response to doses of SARS-CoV-2. This study demonstrated that the response of local and systemic immune effectors to a viral infection varies with viral dose, which either exacerbates the severity of the infection or accelerates its elimination.

Background: A decline in masticatory function may indicate brain dysfunction related to dementia, but the relationship between masticatory function and dementia risk remains unclear. This study aimed to investigate whether masticatory function is associated with the risk of cognitive decline and dementia. Methods: Data were obtained from the nationwide prospective cohort study of randomly sampled community-dwelling Koreans aged ≥ 60 years. The 5,064 non-demented participants, whose number of chewing cycles per bite was assessed by clinical interview, were followed for 8 years with biennial assessments of cognitive performance and clinical diagnoses of all-cause dementia and Alzheimer’s disease (AD). Structural brain magnetic resonance imaging was collected from a subset of cohort participants and their spouses for imaging analyses. Results: Males who chewed ≥ 30 cycles/bite had faster decline in global cognition and memory function and were at higher risk for incident all-cause dementia (hazard ratio [HR], 2.91; 95% confidence interval [CI], 1.18–7.18) and AD (HR, 3.22; 95% CI, 1.14–9.11) compared to males with less than 10 cycles/bite. Additionally, increased chewing cycles in males were associated with reduced brain volume, particularly in regions involved in compensatory cognitive control of mastication. There was no significant association between chewing cycles and the risk of dementia or brain volume in females. Conclusion Older men who frequently chew their meals could be considered a notable population at risk for dementia who should be carefully assessed for their cognitive trajectories.

Adult-onset Still’s disease (AOSD) is a rare systemic inflammatory disease characterized by spiking fever, arthralgia, skin rashes, and hyperferritinemia. The rash is usually salmon-colored, non-itchy, accompanied by fever, and disappears with an improvement of fever. However, in some cases, the rash persisted regardless of fever. Here, we present a case of AOSD with an atypical persistent rash that showed histological findings resembling those of neutrophilic urticarial dermatosis. The patient was a 60-year-old woman with high fever, arthralgia, and a persistent flagellated skin rash. Despite systemic steroid treatment, the patient developed a serious complication: macrophage activation syndrome. Since this case presented with an atypical persistent rash with histological resemblance to neutrophilic urticarial dermatosis, we report its contribution to the further study of AOSD.

Gastric cancer is one of the most common cancers in Korea and the world. Since 2004, this is the 4th gastric cancer guideline published in Korea which is the revised version of previous evidence-based approach in 2018. Current guideline is a collaborative work of the interdisciplinary working group including experts in the field of gastric surgery, gastroenterology, endoscopy, medical oncology, abdominal radiology, pathology, nuclear medicine, radiation oncology and guideline development methodology. Total of 33 key questions were updated or proposed after a collaborative review by the working group and 40 statements were developed according to the systematic review using the MEDLINE, Embase, Cochrane Library and KoreaMed database. The level of evidence and the grading of recommendations were categorized according to the Grading of Recommendations, Assessment, Development and Evaluation proposition. Evidence level, benefit, harm, and clinical applicability was considered as the significant factors for recommendation. The working group reviewed recommendations and discussed for consensus. In the earlier part, general consideration discusses screening, diagnosis and staging of endoscopy, pathology, radiology, and nuclear medicine. Flowchart is depicted with statements which is supported by meta-analysis and references. Since clinical trial and systematic review was not suitable for postoperative oncologic and nutritional follow-up, working group agreed to conduct a nationwide survey investigating the clinical practice of all tertiary or general hospitals in Korea. The purpose of this survey was to provide baseline information on follow up. Herein we present a multidisciplinary-evidence based gastric cancer guideline.

The first edition of ‘A Standardized Pathology Report for Gastric Cancer’ was initiated by the Gastrointestinal Pathology Study Group of the Korean Society of Pathologists and published 17 years ago. Since then, significant advances have been made in the pathologic diagnosis, molecular genetics, and management of gastric cancer (GC). To reflect those changes, a committee for publishing a second edition of the report was formed within the Gastrointestinal Pathology Study Group of the Korean Society of Pathologists. This second edition consists of two parts: standard data elements and conditional data elements.The standard data elements contain the basic pathologic findings and items necessary to predict the prognosis of GC patients, and they are adequate for routine surgical pathology service. Other diagnostic and prognostic factors relevant to adjuvant therapy, including molecular biomarkers, are classified as conditional data elements to allow each pathologist to selectively choose items appropriate to the environment in their institution. We trust that the standardized pathology report will be helpful for GC diagnosis and facilitate large-scale multidisciplinary collaborative studies.