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Abstract Chemical warfare agents (CWAs) pose a threat as gaseous substances and as liquid aerosols, necessitating chemical warfare-protective clothing for soldiers. The paramount consideration lies in the effectiveness of the clothing as a barrier against the pertinent CWAs. This paper presents a dynamic swatch test method aimed at evaluating the performance of such clothing against liquid-phase aerosol penetration. Central to the methodology is a specialized test cell designed to rotate to the left and right, integrated within a laboratory wind tunnel, replicating mission-relevant conditions with varying wind speeds. Utilizing di(2-ethylhexyl) sebacate particles as liquid aerosols, tests were conducted at wind speeds of 1.0, 3.0, and 5.0 m/s. Penetration assessment relied on analyzing particle counts downstream and upstream of the fabric, with preliminary studies showing that higher wind speeds and fabric air permeabilities increase penetration at an equivalent face velocity of 5.0 cm/s. Interestingly, penetration decreased when fabric samples were subjected to rotation. The system and methodology devised demonstrated consistent and repeatable results, offering valuable insights into optimizing the effectiveness of chemical warfare-protective clothing. This research contributes to advancing methodologies for testing protective clothing, crucial for ensuring the safety of military personnel in hazardous environments.

Extranodal natural killer (NK)/T-cell lymphoma, nasal type (ENKTCL-NT) is the most common subtype of Epstein-Barr virus-associated NK/T-cell lymphomas. ENKTCL-NT occurs infrequently in the gastrointestinal tract. In particular, reports of ENKTCL-on NT arising from the stomach are extremely rare. Several clusters of differentiation (CDs) have been useful in recognizing NK-cells, T-cells, and tumor cells of NK/T-cell lymphomas. Among them, the CD56 antigen is considered the most sensitive marker for ENKTCL-NT and is expressed in almost all cases of ENKTCL-NT. Thus, the development of CD56-negative ENKTCL-NT is highly atypical. This paper reports a case of a young Asian female who presented with gastric ulcer bleeding. The patient was histologically diagnosed with ENKTCL-NT. No tumor cells for CD56 were observed, whereas no monoclonality of the T-cell receptor gamma gene rearrangement was detected in the tumor cells. The patient was scheduled for systemic chemotherapy six times and achieved complete remission. Peripheral blood-hematopoietic stem cell transplantation was performed later.

Plexiform neurofibroma (PN) is an uncommon benign tumor, usually associated with neurofibromatosis type 1. As most PNs involve the craniomaxillofacial region, PN of the colon is very rare. Here we present a case of PN involving the sigmoid colon. A 43-year-old male patient presented to the outpatient clinic for the evaluation of an incidentally discovered sigmoid colon mass. A colonoscopic biopsy was performed for the mass, and the result revealed neuronal proliferation. The patient visited the outpatient clinic a year later with symptoms of abdominal pain and stool caliber change. Biopsy was repeated for the sigmoid colon mass, and the results showed mucosal Schwann cell proliferation and S-100 immunostaining positivity. Computed tomography and magnetic resonance imaging were performed for further evaluation, and neurofibroma or schwannoma was suspected based on the imaging studies. For an accurate diagnosis, the patient underwent surgery to remove the sigmoid colon mass. The final diagnosis of the mass was confirmed as PN. We hereby report a rare case of PN involving the sigmoid colon that could not be diagnosed before surgery.

Gastric wall abscess, a localized form of phlegmonous gastritis, is a rare complication of endoscopic resection. We report the first case of gastric wall abscess developing after endoscopic submucosal dissection in Korea. A 72-year-old woman visited our clinic to receive treatment for gastric adenoma. The patient successfully underwent endoscopic submucosal dissection with no complications. The final diagnosis was well-differentiated tubular adenocarcinoma. We performed follow-up endoscopy 10 weeks later and found a large subepithelial lesion on the posterior wall of the gastric antrum. Abdominal computed tomography revealed hypodense wall thickening and a 5 cm heterogenous multilobular mass in the submucosal layer of the gastric antrum. Submucosal invasion with mucin-producing adenocarcinomas could therefore not be excluded. The patient agreed to undergo additional gastrectomy due to the possibility of a highly malignant lesion. The final diagnosis was acute suppurative inflammation with the formation of multiple abscesses in the mural layers and omentum. The patient was discharged with no complications.

Background Benign esophageal strictures are treated endoscopically, often with balloon dilatation (BD) or bougie dilators. However, recurrent esophageal strictures have been reported after BD, and severe complications sometimes occur. The aim of this study was to compare the efficacy and complications of endoscopic incisional therapy (EIT) and BD for benign esophageal strictures. Methods We retrospectively reviewed patients who underwent BD or EIT as primary treatment for benign esophageal strictures between July 2014 and June 2021. Technical success was defined as restoration of the lumen diameter with

Background/Aims: Dietary factors can aggravate the symptoms of irritable bowel syndrome (IBS). Many IBS patients try restrictive diets to relieve their symptoms, but the types of diets with an exacerbating factor are unknown. Therefore, this paper reports the results of a systematic review and network meta-analysis of randomized-controlled trials (RCTs) reviewing the efficacy of food restriction diets in IBS. Methods: The MEDLINE, EMBASE, Cochrane Central Register of Controlled Trials, and Clinicaltrials.gov databases were searched until July 21, 2021, to retrieve RCTs assessing the efficacy of restriction diets in adults with IBS. Two independent reviewers performed the eligibility assessment and data abstraction. RCTs that evaluated a restriction diet versus a control diet and assessed the improvement in global IBS symptoms were included. These trials reported a dichotomous assessment of the overall response to therapy. Results: A total of 1,949 citations were identified. After full-text screening, 14 RCTs were considered eligible for the systematic review and network meta-analysis. A starch- and sucrose-reduced diet and a diet with low-fermentable oligosaccharides, disaccharides, monosaccharides, and polyols (FODMAPs) showed significantly better results than a usual diet. Symptom flare-ups in patients on a gluten- free diet were also significantly lower than in those on high-gluten diets. Conclusions: These findings showed that the starch- and sucrose-reduced, low FODMAP, and gluten-free diets had superior effects in reducing IBS symptoms. Further studies, including head-to-head trials will be needed to establish the effectiveness of dietary restrictions on IBS symptoms.

Neuroendocrine tumors (NETs) that arise from neuroendocrine cells can develop in most organs; however, it is rarely found in the duodenal papilla. Conversely, gastrointestinal stromal tumors (GISTs), which are mostly asymptomatic and detected incidentally, are usually found in the stomach and very rarely occur metachronously with NETs. A 42-year-old female with no specific underlying disease underwent gastroscopy due to epigastric pain. Biopsy of enlarged major and minor duodenal papilla confirmed the diagnosis of a NET. Endoscopic papillectomy of the major and minor papillae was performed. Multiple duodenal and jejunal submucosal nodules were seen on biliary CT performed at the 30 months follow-up. Pylorus-preserving pancreaticoduodenectomy was performed due to the suspicion of multiple recurrent NETs and muscularis propria involvement on endoscopic ultrasound. Surgical specimen biopsy confirmed the diagnosis of multiple duodenal and jejunal GIST lesions and a metastatic NET in the duodenal lymph node. We report a rare case of a GIST detected in the duodenum during follow-up after the diagnosis and papillectomy of duodenal papilla NET.

Abstract Background Dysbiosis of ulcerative colitis (UC) has been frequently investigated using readily accessible stool samples. However, stool samples might insufficiently represent the mucosa-associated microbiome status. We hypothesized that luminal contents including loosely adherent luminal bacteria after bowel preparation may be suitable for diagnosing the dysbiosis of UC. Methods This study included 16 patients with UC (9 men and 7 women, mean age: 52.13 ± 14.09 years) and 15 sex- and age-matched healthy individuals (8 men and 7 women, mean age: 50.93 ± 14.11 years). They donated stool samples before colonoscopy and underwent luminal content aspiration and endoscopic biopsy during the colonoscopy. Then, the composition of each microbiome sample was analyzed by 16S rRNA-based next-generation sequencing. Results The microbiome between stool, luminal contents, and biopsy was significantly different in alpha and beta diversities. However, a correlation existed between stool and luminal contents in the Procrustes test (p = 0.001) and Mantel test (p = 0.0001). The stool microbiome was different between patients with UC and the healthy controls. Conversely, no difference was found in the microbiome of luminal content and biopsy samples between the two subject groups. The microbiome of stool and lavage predicted UC, with AUC values of 0.85 and 0.81, respectively. Conclusion The microbiome of stool, luminal contents, and biopsy was significantly different. However, the microbiome of luminal contents during colonoscopy can predict UC, with AUC values of 0.81. Colonoscopic luminal content aspiration analysis could determine microbiome differences between patients with UC and the healthy control, thereby beneficial in screening dysbiosis via endoscopy. Trial registration: This trial was registered at http://cris.nih.go.kr . Registration No.: KCT0003352), Date: 2018–11-13.

Duodenal varices are a serious complication of portal hypertension. Bleeding from duodenal varices is rare, but when bleeding does occur, it is massive and can be fatal. Unfortunately, the optimal therapeutic modality for duodenal variceal bleeding is unclear. This paper presents a patient with duodenal variceal bleeding that was managed successfully using percutaneous trans-splenic variceal obliteration (PTVO). A 56-year-old man with a history of alcoholic cirrhosis presented with a 6-day history of melena. Emergency esophagogastroduodenoscopy revealed a large, bluish mass with a nipple sign in the second portion of the duodenum. Coil embolization of the duodenal varix was performed via a trans-splenic approach (i.e., PTVO). The patient no longer complained of melena after treatment. The duodenal varix was no longer visible at the follow-up esophagogastroduodenoscopy performed three months after PTVO. The use of PTVO might be a viable option for the treatment of duodenal variceal bleeding.

Summary Poly(lactate‐co‐glycolate), PLGA, is a representative synthetic biopolymer widely used in medical applications. Recently, we reported one‐step direct fermentative production of PLGA and its copolymers by metabolically engineered Escherichia coli from xylose and glucose. In this study, we report development of metabolically engineered E. coli strains for the production of PLGA and poly(d‐lactate‐co‐glycolate‐co‐d‐2‐hydroxybutyrate) having various monomer compositions from xylose as a sole carbon source. To achieve this, the metabolic flux towards Dahms pathway was modulated using five different synthetic promoters for the expression of Caulobacter crescentus XylBC. Further metabolic engineering to concentrate the metabolic flux towards d‐lactate and glycolate resulted in production of PLGA and poly(d‐lactate‐co‐glycolate‐co‐d‐2‐hydroxybutyrate) with various monomer fractions from xylose. The engineered E. coli strains produced polymers containing 8.8–60.9 mol% of glycolate up to 6.93 g l−1 by fed‐batch cultivation in a chemically defined medium containing xylose. Finally, the biocompatibility of poly(d‐lactate‐co‐glycolate‐co‐d‐2‐hydroxybutyrate) was confirmed by live/dead assay using human mesenchymal stem cells.

Background/Aims In Korea, changes in the prevalence of irritable bowel syndrome (IBS) after the Rome IV update have not been extensively studied. The aim of this study is to compare the prevalence and psychosocial risk factors of IBS according to Rome III and Rome IV criteria in medical and nursing students. Methods From August 13, 2021 to October 22, 2021, participants were enrolled and surveyed online. The survey includes general and specific questions for disease diagnosis and regarding participants’ social and psychological characteristics using the 36-item short form survey, the Brief Encounter Psychosocial Instrument-Korean version, and the Hospital Anxiety and Depression Scale. Results In total, 338 medical students and 102 nursing students completed the survey. IBS was diagnosed in 78 students (17.7%) using Rome III criteria and in 51 students (11.6%) using Rome IV criteria. Significant differences in physical functioning score and severity score were observed between patients diagnosed using Rome IV criteria and patients diagnosed using Rome III criteria. Multiple logistic regression revealed that severity score (adjusted odds ratio = 1.01; 95% confidence interval: 1.00-1.21; P = 0.022) is the only predictor of IBS that differentiates Rome IV criteria from Rome III criteria. Conclusions Even after updating the Rome IV diagnostic criteria, the prevalence of IBS in medical and nursing students in Korea remained high. Patients who met the Rome IV criteria had more severe symptoms and lower quality of life than patients who met the Rome III criteria. [ABSTRACT FROM AUTHOR]

In this study, we present a method for assembling biofunctionalized paper into a multiform structured scaffold system for reliable tissue regeneration using an origami-based approach. The surface of a paper was conformally modified with a poly(styrene-comaleic anhydride) layer via initiated chemical vapor deposition followed by the immobilization of poly-L-lysine (PLL) and deposition of Ca2+. This procedure ensures the formation of alginate hydrogel on the paper due to Ca2+ diffusion. Furthermore, strong adhesion of the alginate hydrogel on the paper onto the paper substrate was achieved due to an electrostatic interaction between the alginate and PLL. The developed scaffold system was versatile and allowed area-selective cell seeding. Also, the hydrogel-laden paper could be folded freely into 3D tissue-like structures using a simple origamibased method. The cylindrically constructed paper scaffold system with chondrocytes was applied into a three-ring defect trachea in rabbits. The transplanted engineered tissues replaced the native trachea without stenosis after 4 wks. As for the custom- built scaffold system, the hydrogel-laden paper system will provide a robust and facile method for the formation of tissues mimicking native tissue constructs. [ABSTRACT FROM AUTHOR]

The article demonstrates that the prior acquired resistance to paclitaxel relays diverse epidermal growth factor receptor–tyrosine kinase inhibitors (EGFR-TKIs)-targeted therapy persistence mechanisms. It identifies that the paclitaxel-resistant cells enrich their stemness profile and rewire their glucose metabolism and an apoptotic control pathway to collectively compromise an adaptive stress response during the second-line of therapeutic pressure.

Neurofibromatosis type 1 (NF1) is a rare genetic disease. Precapillary pulmonary hypertension (PH) with NF1 is an extremely severe complication. A 65-year-old woman was admitted in our hospital with 3-year history of gradually worsening dyspnea on exertion (New York Heart Association functional class III-IV). Considering her clinical feature and examination findings, she could be diagnosed as PH associated with NF1. She was treated with endothelin receptor antagonist. However her dyspnea was not significantly improved. This is the first Korean case of NF1 patient with PH which confirmed with right heart catheterization.