The emergence of brain organoids as a model system has been a tremendously exciting development in the field of neuroscience. Brain organoids are a gateway to exploring the intricacies of human-specific neurogenesis that have so far eluded the neuroscience community. Regardless, current culture methods have a long way to go in terms of accuracy and reproducibility. To perfectly mimic the human brain, we need to recapitulate the complex in vivo context of the human fetal brain and achieve mature neural circuitry with an intact cytoarchitecture. In this review, we explore the major challenges facing the current brain organoid systems, potential technical breakthroughs to advance brain organoid techniques up to levels similar to an in vivo human developing brain, and the future prospects of this technology.

BACKGROUND: In the present study, the prevalence and risk factors for acquisition of extended-spectrum β-lactamase (ESBL)-producing Escherichia coli in intensive care unit (ICU) settings without outbreak in the situation of widespread sequence type (ST) 131 ESBL-producing E. coli in a Korean community was investigated. METHODS: Consecutive and prospective screening of ESBL-producing E. coli colonization was performed in all patients admitted to surgical or medical ICUs within 48 hours for two months. ESBL genotype was determined based on PCR and sequencing. PCR for O16-ST131/O25-ST131 was performed for all ESBL producers. Clinical information was obtained from a review of electronic medical record to determine the risk factors for ESBL-producing E. coli colonization. RESULTS: The colonization rate of ESBL-producing E. coli at ICU admission was 14.9% (42/281). CTX-M-15 (N=15), CTX-M-14 (N=12), and CTX-M-27 (N=10) were commonly detected using PCR of ESBL genes. Approximately half (45.2%, 19/42) of ESBL producers were ST131 clone with 14 ST131-O25 and 5 ST131-O16. In univariate analysis, independent risk factor for acquisition of ESBL-producing E. coli compared with controls was ICU type (odds ratio, 2.05; P < 0.032); however, site of acquisition, previous antibiotic use, and hospital stay were not significant risk factors. CONCLUSION: In this study, the colonization of ESBL-producing E. coli at ICU admission without outbreak was frequent and it could be an infection source, regardless of acquisition site. We recommend routine use of ASC to control endemic ESBL-producing E. coli considering the wide distribution of ST131-ESBL-producing E. coli in the Korean community.
Clone Cells ; Colon ; Electronic Health Records ; Escherichia coli* ; Escherichia* ; Genotype ; Humans ; Intensive Care Units ; Length of Stay ; Mass Screening ; Polymerase Chain Reaction ; Prevalence ; Prospective Studies ; Risk Factors

Background/Aims: Gastric neuroendocrine tumors (GNETs), once rare, have become more prevalent due to the increased use of endoscopy and increased physician awareness. The clinical characteristics and long-term outcomes of GNET management were explored in this study. Methods: The clinical data of 69 patients who treated at Seoul National University Hospital between January 2013 and October 2023 were retrospectively studied. Baseline characteristics, recurrence rates, associated factors, and overall survival rates were analyzed. Results: Of the tumors, 71.0% were grade 1, 24.6% were grade 2, 1.4% were grade 3, and 2.9% were poorly differentiated. In terms of tumor type, 69.6% were type I, 1.4% were type II, and 29.0% were type III. A significant proportion of patients with grade 1 tumors received more endoscopic treatment, whereas a significant proportion of patients with grade 2 tumors underwent surgery or chemotherapy (p=0.015). The overall 5-year survival and recurrence rates were 93.8% and 7.25% (5/69), respectively. Among five patients who experienced recurrence, three had metachronous recurrence, all of which were type I; the remaining two patients exhibited distant hepatic metastasis, encompassing types I and III. The time to recurrence was 1 to 9.8 years.Margin positivity (p=0.002) and invasion deeper than the submucosal layer (p=0.007) were associated with higher recurrence rates. However, there was no significant association between recurrence and intestinal metaplasia, atrophic gastritis, or Helicobacter pylori infection. Conclusions Most patients with GNETs in this study had grade I and type I tumors, and the overall prognosis was favorable. Patients with risk factors for recurrence warrant further investigation. Those presenting margin positivity or deep invasion after resection should be closely monitored and undergo follow-up examinations, as necessary.

Background/Aims: Gastric neuroendocrine tumors (GNETs), once rare, have become more prevalent due to the increased use of endoscopy and increased physician awareness. The clinical characteristics and long-term outcomes of GNET management were explored in this study. Methods: The clinical data of 69 patients who treated at Seoul National University Hospital between January 2013 and October 2023 were retrospectively studied. Baseline characteristics, recurrence rates, associated factors, and overall survival rates were analyzed. Results: Of the tumors, 71.0% were grade 1, 24.6% were grade 2, 1.4% were grade 3, and 2.9% were poorly differentiated. In terms of tumor type, 69.6% were type I, 1.4% were type II, and 29.0% were type III. A significant proportion of patients with grade 1 tumors received more endoscopic treatment, whereas a significant proportion of patients with grade 2 tumors underwent surgery or chemotherapy (p=0.015). The overall 5-year survival and recurrence rates were 93.8% and 7.25% (5/69), respectively. Among five patients who experienced recurrence, three had metachronous recurrence, all of which were type I; the remaining two patients exhibited distant hepatic metastasis, encompassing types I and III. The time to recurrence was 1 to 9.8 years.Margin positivity (p=0.002) and invasion deeper than the submucosal layer (p=0.007) were associated with higher recurrence rates. However, there was no significant association between recurrence and intestinal metaplasia, atrophic gastritis, or Helicobacter pylori infection. Conclusions Most patients with GNETs in this study had grade I and type I tumors, and the overall prognosis was favorable. Patients with risk factors for recurrence warrant further investigation. Those presenting margin positivity or deep invasion after resection should be closely monitored and undergo follow-up examinations, as necessary.

Background/Aims: Gastric neuroendocrine tumors (GNETs), once rare, have become more prevalent due to the increased use of endoscopy and increased physician awareness. The clinical characteristics and long-term outcomes of GNET management were explored in this study. Methods: The clinical data of 69 patients who treated at Seoul National University Hospital between January 2013 and October 2023 were retrospectively studied. Baseline characteristics, recurrence rates, associated factors, and overall survival rates were analyzed. Results: Of the tumors, 71.0% were grade 1, 24.6% were grade 2, 1.4% were grade 3, and 2.9% were poorly differentiated. In terms of tumor type, 69.6% were type I, 1.4% were type II, and 29.0% were type III. A significant proportion of patients with grade 1 tumors received more endoscopic treatment, whereas a significant proportion of patients with grade 2 tumors underwent surgery or chemotherapy (p=0.015). The overall 5-year survival and recurrence rates were 93.8% and 7.25% (5/69), respectively. Among five patients who experienced recurrence, three had metachronous recurrence, all of which were type I; the remaining two patients exhibited distant hepatic metastasis, encompassing types I and III. The time to recurrence was 1 to 9.8 years.Margin positivity (p=0.002) and invasion deeper than the submucosal layer (p=0.007) were associated with higher recurrence rates. However, there was no significant association between recurrence and intestinal metaplasia, atrophic gastritis, or Helicobacter pylori infection. Conclusions Most patients with GNETs in this study had grade I and type I tumors, and the overall prognosis was favorable. Patients with risk factors for recurrence warrant further investigation. Those presenting margin positivity or deep invasion after resection should be closely monitored and undergo follow-up examinations, as necessary.

Background/Aims: Gastric neuroendocrine tumors (GNETs), once rare, have become more prevalent due to the increased use of endoscopy and increased physician awareness. The clinical characteristics and long-term outcomes of GNET management were explored in this study. Methods: The clinical data of 69 patients who treated at Seoul National University Hospital between January 2013 and October 2023 were retrospectively studied. Baseline characteristics, recurrence rates, associated factors, and overall survival rates were analyzed. Results: Of the tumors, 71.0% were grade 1, 24.6% were grade 2, 1.4% were grade 3, and 2.9% were poorly differentiated. In terms of tumor type, 69.6% were type I, 1.4% were type II, and 29.0% were type III. A significant proportion of patients with grade 1 tumors received more endoscopic treatment, whereas a significant proportion of patients with grade 2 tumors underwent surgery or chemotherapy (p=0.015). The overall 5-year survival and recurrence rates were 93.8% and 7.25% (5/69), respectively. Among five patients who experienced recurrence, three had metachronous recurrence, all of which were type I; the remaining two patients exhibited distant hepatic metastasis, encompassing types I and III. The time to recurrence was 1 to 9.8 years.Margin positivity (p=0.002) and invasion deeper than the submucosal layer (p=0.007) were associated with higher recurrence rates. However, there was no significant association between recurrence and intestinal metaplasia, atrophic gastritis, or Helicobacter pylori infection. Conclusions Most patients with GNETs in this study had grade I and type I tumors, and the overall prognosis was favorable. Patients with risk factors for recurrence warrant further investigation. Those presenting margin positivity or deep invasion after resection should be closely monitored and undergo follow-up examinations, as necessary.

Anastomotic leaks and fistulas are significant complications of gastric surgery that potentially lead to increased postoperative morbidity and mortality. Surgical intervention is reserved for cases with severe symptoms or hemodynamic instability; however, surgery carries a higher risk of complications. With advancements in endoscopic treatment options, endoscopic approaches have emerged as the primary choice for managing these complications. Endoscopic clipping is a traditional method comprising 2 main categories:through-the-scope clips and over-the-scope clips. Through-the-scope clips are user friendly and adaptable to various clinical scenarios, whereas over-the-scope clips can close larger defects. Another promising approach is endoscopic stent insertion, which has shown a high success rate for leak closure, although vigilant monitoring is required to monitor stent migration. Infection control is essential in post-surgical leakage cases, and endoscopic internal drainage provides a relatively safe and noninvasive means to manage fluids, contributing to infection control and wound healing promotion. Endoscopic suturing offers full-thickness wound closure, but requires additional training and endoscopic versatility. As a promising tool, endoscopic vacuum therapy potentially surpasses stent therapy by draining inflammatory materials and closing defects. Furthermore, the use of tissue sealants, such as fibrin glue and cyanoacrylate, has been reported to be effective in selected situations.The choice of endoscopic device should be tailored to individual cases and specific patient conditions, with careful consideration of the nature of the defect. Further extensive studies involving larger patient populations are required to provide more robust evidence on the efficacy of endoscopic approach in managing post-gastric anastomotic leaks.

In this study, we report three cases in which two species of the Bacteroides fragilis group, 'Bacteroides nordii' and 'Bacteroides salyersiae', were isolated from peritoneal fluid cultures from post-operative peritonitis patients. The two species of the B. fragilis group were initially misidentified as B. fragilis/Bacteroides stercoris and Bacteroides ovatus by Rapid ID 32A (bioMérieux, France), and finally confirmed as B. nordii and B. salyersiae using matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS) and 16s rRNA sequencing. For the identification of anaerobes, particularly B. fragilis group organisms, MALDI-TOF MS is a useful method not only because of its concordance with 16S rRNA sequencing results, but also because of its rapidity and simple procedure.
Ascitic Fluid ; Bacteroides fragilis ; Bacteroides* ; Humans ; Mass Spectrometry ; Peritonitis* ; Spectrum Analysis

BACKGROUND/AIMS: Spontaneous intramural small bowel hematoma (SISBH) is an extremely rare complication of anticoagulant or antiplatelet therapy. We assessed the clinical characteristics and outcomes of patients with SISBH according to the anatomical location of the hematoma. METHODS: From January 2003 to February 2016, medical records for all patients hospitalized for SISBH at 2 tertiary referral hospitals were retrospectively reviewed. The primary outcome was requirement for surgery. RESULTS: A total of 37 patients were enrolled. The mean age was 74.1 years. Among them, 33 patients (89.2%) were taking anticoagulant and/or antiplatelet agents. Duodenal intramural hematoma was detected in 4 patients (10.8%), jejunal in 16 (43.2%), and ileal in 17 (45.9%). Compared to jejunal and ileal involvement, duodenal intramural hematoma was significantly associated with high Charlson comorbidity index and low levels of white blood cells, hemoglobin, and platelets in the blood. SISBH in the duodenum was related to thrombocytopenia in 3 patients following systemic chemotherapy for malignancy. All patients with SISBH showed clinical improvement with conservative therapy. Mean length of hospital stay was 9.35 days. Independent predictors of a hospital stay of more than 7 days were body weight less than 60 kg (odds ratio [OR], 12.213; 95% confidence interval [CI], 1.755–84.998; P=0.011) and a history of cerebrovascular accidents (OR, 6.667; 95% CI, 1.121–39.650; P=0.037). CONCLUSIONS: Compared to jejunal and ileal involvement, thrombocytopenia may result in spontaneous duodenal intramural hematoma among patients who are treated with systemic chemotherapy for malignancies. Patients with SISBH have excellent clinical outcomes with conservative therapy regardless of the anatomical location of the hematoma.
Body Weight ; Cohort Studies ; Comorbidity ; Drug Therapy ; Duodenum ; Hematoma ; Humans ; Intestine, Small ; Length of Stay ; Leukocytes ; Medical Records ; Platelet Aggregation Inhibitors ; Retrospective Studies ; Stroke ; Tertiary Care Centers ; Thrombocytopenia ; Treatment Outcome