Visceral Adipose Tissue Reduction Measured by Deep Neural Network Architecture Improved Reflux Esophagitis Endoscopic Grade.

INTRODUCTION: Visceral obesity is a risk factor for reflux esophagitis (RE). We investigated the risk of RE according to visceral adipose tissue (VAT) measured by deep neural network architecture using computed tomography (CT) and evaluated the longitudinal association between abdominal adipose tissue changes and the disease course of RE. METHODS: Individuals receiving health checkups who underwent esophagogastroduodenoscopy (EGD) and abdominal CT at Seoul National University Healthcare System Gangnam Center between 2015 and 2016 were included. Visceral and subcutaneous adipose tissue areas and volumes were measured using a deep neural network architecture and CT. The association between the abdominal adipose tissue area and volume and the risk of RE was evaluated. Participants who underwent follow-up EGD and abdominal CT were selected; the effects of changes in abdominal adipose tissue area and volume on RE endoscopic grade were investigated using Cox proportional hazards regression. RESULTS: We enrolled 6,570 patients who underwent EGD and abdominal CT on the same day. RE was associated with male sex, hypertension, diabetes, excessive alcohol intake, current smoking status, and levels of physical activity. The VAT area and volume increased the risk of RE dose-dependently. A decreasing VAT volume was significantly associated with improvement in RE endoscopic grade (hazard ratio: 3.22, 95% confidence interval: 1.82-5.71). Changes in subcutaneous adipose tissue volume and the disease course of RE were not significantly correlated. DISCUSSION: Visceral obesity is strongly associated with RE. VAT volume reduction was prospectively associated with improvement in RE endoscopic grade dose-dependently. Visceral obesity is a potential target for RE treatment.

Superior lymph node harvest by fluorescent lymphography during minimally invasive gastrectomy for gastric cancer patients with high body mass index.

BACKGROUND: Fluorescent lymphography (FL) using indocyanine green (ICG) allows for the visualization of all draining lymph nodes (LNs), thereby increasing LN retrieval. However, no studies have assessed the efficacy of FL in high body mass index (BMI) gastric cancer patients, even as LN yield decreases with increasing BMI in gastrectomy. This study aimed to investigate the influence of FL on LN retrieval in high BMI gastric cancer patients. METHODS: Gastric cancer patients who underwent laparoscopic or robotic gastrectomies from 2013 to 2021 were included. Patients were classified into two groups, with FL (FL group) or without FL (non-FL group). The effect of FL on LN retrieval was assessed by BMI. Inverse probability of treatment weighting (IPTW) was used to ensure comparability between groups. RESULTS: Retrieved LN number decreased as BMI increased regardless of FL application (P < 0.001). According to the IPTW analysis, the mean retrieved LN number was significantly higher in the FL group (48.4 ± 18.5) than in the non-FL group (39.8 ± 16.3, P < 0.001), irrespective of BMI. The FL group exhibited a significantly higher proportion of patients with 16 or more LNs (99.5%) than the non-FL group (98.1%, P < 0.001). The FL group also had a significantly higher proportion of patients with 30 or more LNs (86.6%) than the non-FL group (72.2%, P < 0.001). In both the normal and high-BMI patients, the FL group had a significantly larger percentage of patients with a higher nodal classification than the non-FL group. CONCLUSION: FL resulted in more LN retrieval, even in high BMI patients. FL ensures accurate staging by maintaining the appropriate retrieved LN number in high BMI gastric cancer patients.

Identifying the best candidates for reduced port gastrectomy.

BACKGROUND: Previous studies have focused on the non-inferiority of RPG compared with conventional port gastrectomy (CPG); however, we assumed that some candidates might derive more significant benefit from RPG over CPG. METHODS: We retrospectively analyzed the clinicopathological and perioperative parameters of 1442 patients with gastric cancer treated by gastrectomy between 2009 and 2022. The C-reactive protein level on postoperative day 3 (CRPD3) was used as a surrogate parameter for surgical trauma. Patients were grouped according to the extent of gastrectomy [subtotal gastrectomy (STG) or total gastrectomy (TG)] and lymph node dissection (D1+ or D2). The degree of surgical trauma, bowel recovery, and hospital stay between RPG and CPG was compared among those patient groups. RESULTS: Of 1442 patients, 889, 354, 129, and 70 were grouped as STGD1+, STGD2, TGD1+, and TGD2, respectively. Compared with CPG, RPG significantly decreased CRPD3 only among patients in the STGD1+ group (CPG: n = 653, 84.49 mg/L, 95% CI 80.53-88.45 vs. RPG: n = 236, 70.01 mg/L, 95% CI 63.92-76.09, P < 0.001). In addition, the RPG method significantly shortens bowel recovery and hospital stay in the STGD1+ (P < 0.001 and P < 0.001), STGD2 (P < 0.001 and P < 0.001), and TGD1+ (P = 0.026 and P = 0.007), respectively. No difference was observed in the TGD2 group (P = 0.313 and P = 0.740). CONCLUSIONS: The best candidates for RPG are patients who undergo STGD1+, followed by STGD2 and TG D1+, considering the reduction in CRPD3, bowel recovery, and hospital stay.

Da Vinci robot-assisted endoscopic full-thickness gastric resection with regional lymph node dissection using a 3D near-infrared video system: a single-center 5-year clinical outcome.

BACKGROUND: Endoscopic full-thickness gastric resection (EFTGR) with regional lymph node dissection (LND) has been used for early gastric cancer (EGC) exceeding the indications for endoscopic submucosal dissection (ESD). The extent of the dissected lymph nodes is crucial. A 3D near-infrared (NIR) video robot system significantly enhances visualization of the lymphatic system. However, this system has not been used in EFTGR with LND. Thus, this study assessed the benefits of the 3D NIR video robot system in a clinical setting. METHODS: Between February 2015 and September 2018, 24 patients with EGC exceeding the indications for ESD were treated with EFTGR and LND using a 3D NIR video system with the da Vinci surgical robot. Indocyanine green (ICG) was injected endoscopically around the tumor, and basin node (BN) dissection around the nodes was examined using the 3D NIR video system of the da Vinci Si surgical robot. Subsequently, robot-assisted EFTGR was performed. The primary outcome was the 5-year survival rate. RESULT: During a 5-year follow-up of all 24 patients, an 80-year-old patient with an ulcer and T2 invasion was lost to follow-up. Among the remaining 23 patients, no mortality or recurrence was observed. CONCLUSION: No metastasis or mortality occurred using the da Vinci robot-assisted EFTGR with LLND and a 3D NIR video system for patients who required radical gastrectomy for EGC in over 5 years. Hence, this may be a safe and effective method for radical gastrectomy; further studies are required confirming its effectiveness.

Antenatal diagnosis and management of fetal inguinoscrotal hernia: A case report with literature review.

Primary inguinal hernia is a common pediatric surgical condition with an incidence of 1%-4%, which is higher in male or premature newborns. It is characterized by the protrusion of abdominal contents through inguinal canal in newborns. However, prenatal fetal inguinal hernia is a rare condition because the pressure of amniotic fluid is similar to intra-abdominal pressure. Only 19 English publications were found with 21 reported cases until now. We report belatedly discovered inguinoscrotal hernia at 38+0 weeks' gestation. Usually, the fetal testicular descent begins from 24 to 25 weeks' gestation, and it is found after 32 weeks of gestational age in 97% of the fetuses. Therefore, it is necessary to get into the habit of checking fetal testicles during routine US after at least 32 weeks of gestational age.

Synergistic Anti-Cancer Effects of ERB-041 and Genistein through Estrogen Receptor Suppression-Mediated PI3K/AKT Pathway Downregulation in Canine Mammary Gland Tumor Cells.

Canine-mammary-gland tumors (CMTs) are prevalent in female dogs, with approximately 50% of them being malignant and often presenting as inoperable owing to their size or metastasis. Owing to poor outcomes, effective alternatives to conventional chemotherapy for humans are necessary. Two estrogen receptors, estrogen receptor alpha (ERα) and estrogen receptor beta (ERß), which act in opposition to each other, are involved, and CMT growth involves ERα through the phosphoinositide 3-kinases (PI3K)/AKT pathway. In this study, we aimed to identify the synergistic anti-cancer effects of ERB-041, an ERß agonist, and genistein, an isoflavonoid from soybeans known to have ERß-specific pseudo-estrogenic actions, on CMT-U27 and CF41.Mg CMT cell lines. ERB-041 and genistein synergistically inhibited cell proliferation and increased the number of annexin V-positive cells in both cell lines. Furthermore, we observed a synergistic increase in the Bax/Bcl-2 ratio and cleaved caspase-3 expression. Additionally, cell-cycle arrest occurred through the synergistic regulation of cyclin D1 and cyclin-dependent kinase 4 (CDK4). We also found a synergistic decrease in the expression of ERα, and the expression of proteins involved in the PI3K/AKT pathway, including p-PI3K, phosphatase and tensin homolog (PTEN), AKT, and mechanistic target of rapamycin (mTOR). In conclusion, ERB-041 and genistein exhibited a synergistic anticancer effect on CMTs, suggesting that cotreatment with ERB-041 and genistein is a promising treatment for CMTs.

Physiological and Molecular Modulations to Drought Stress in the Brassica Species.

Climate change, particularly drought stress, significantly impacts plant growth and development, necessitating the development of resilient crops. This study investigated physiological and molecular modulations to drought stress between diploid parent species and their polyploid progeny in the Brassica species. While no significant phenotypic differences were observed among the six species, drought stress reduced growth parameters by 2.4% and increased oxidative stress markers by 1.4-fold. Drought also triggered the expression of genes related to stress responses and led to the accumulation of specific metabolites. We also conducted the first study of perfluorooctane sulfonic acid (PFOS) levels in leaves as a drought indicator. Lower levels of PFOS accumulation were linked to plants taking in less water under drought conditions. Both diploid and polyploid species responded to drought stress similarly, but there was a wide range of variation in their responses. In particular, responses were less variable in polyploid species than in diploid species. This suggests that their additional genomic components acquired through polyploidy may improve their flexibility to modulate stress responses. Despite the hybrid vigor common in polyploid species, Brassica polyploids demonstrated intermediate responses to drought stress. Overall, this study lays the framework for future omics-level research, including transcriptome and proteomic studies, to deepen our understanding of drought tolerance mechanisms in Brassica species.

A pilot clinical study to evaluate feasibility of using single patient classifier as a prognostic test in stage II-III gastric cancer patients.

Objective: Precision medicine approaches emphasize the importance of reliable prognostic tools for guiding individualized therapy decisions. In this study, we evaluated the clinical feasibility of the single patient classifier (SPC) test, a new clinical-grade prognostic assay, in stage II-III gastric cancer patients. Methods: A prospective multicenter study was conducted, involving 237 patients who underwent gastrectomy between September 2019 and August 2020 across nine hospitals. The SPC test was employed to stratify patients into risk groups, and its feasibility and performance were evaluated. The primary endpoint was the proportion of the cases in which the test results were timely delivered before selecting postoperative treatment. Furthermore, 3-year disease-free survivals of risk groups were analyzed. Results: The SPC test met the primary endpoint criteria. The 99.5% of SPC tests were timely delivered to hospitals before the postoperative treatment started. In a clinical setting, the median time from the specimen transfer to laboratory to the result delivery to hospital was 4 d. Furthermore, 3-year disease-free survivals were significantly different between risk groups classified with SPC tests. Conclusions: This study highlights the SPC test's feasibility in offering crucial information timely delivered for making informed decisions regarding postoperative treatment strategies. It also provides evidence to support the implementation of a future prospective clinical trial aimed at evaluating the clinical utility of the SPC test in guiding personalized treatment decisions for gastric cancer patients.

Atopic dermatitis is associated with the clinical course of inflammatory bowel disease.

OBJECTIVES: There are a few studies about the relationship between inflammatory bowel disease (IBD) and atopic dermatitis (AD). It is implied that both diseases have common pathophysiologic mechanisms and can affect each other. However, little information is available on the effect of AD on the clinical course of patients with IBD. METHODS: This is a multi-center, retrospective, observational study. We define AD as a chronic eczematoid dermatosis diagnosed by dermatologists. Patients with concurrent IBD and AD were defined as a case group. Age, gender, and IBD subtype-matched patients without AD were included as a reference group. RESULTS: The numbers of patients in the case and reference groups were 61 and 122 respectively. There was a significantly shorter biologics-free survival in the case group than that in the reference group according to the multivariable-adjusted Cox regression analysis with the onset age, disease duration, smoking status, use of steroid, use of immunomodulator, initial C-reactive protein, initial erythrocyte sedimentation rate, presence of other allergic diseases and initial disease severity [hazard ratio (HR) 1.828, 95% confidence interval (CI) 1.022-3.271, p = .042]. The trend was consistent in the subgroup analysis with ulcerative colitis (HR 3.498, 95% CI 1.066-11.481, p = .039), but not with Crohn's disease (HR 1.542, 95% CI 0.720-3.301, p = .265). CONCLUSIONS: AD showed a significant effect on the biologics-free survival of patients with IBD and especially the UC subtype. Further mechanistic research is required to elucidate the pathogenesis of AD on the clinical course of IBD.

Spatiotemporal non-stationarity in green space and stress relationships: Recent evidence from South Korea.

A growing body of literature has linked exposure to "green space" (vegetation-rich areas) and other forms of nature to mental health. Exposure-outcome associations at regional or national scales can overlook local associations that define how geographically distinct populations may experience nature differently. Large-scale results might downplay the importance of lived experiences and heterogeneity of human-nature relationships at local scales. The current study examines three types of vegetative cover and identifies how they are associated with perceived stress in South Korea during and before the COVID-19 pandemic. We find forest cover is consistently negatively associated with perceived stress at nationwide scales. In contrast, grass cover and the normalized difference vegetation index (NDVI) show mixed associations with perceived stress at nationwide scales. Models accounting for spatial and temporal variability demonstrate that associations of forest cover, grass cover, and NDVI with perceived stress varies across the country and the study's four-year time horizon. Local governments may need divergent urban greening strategies for health promotion that respond to their specific sociodemographic and pre-existing environmental conditions.

Anti-cancer effect of palmatine through inhibition of the PI3K/AKT pathway in canine mammary gland tumor CMT-U27 cells.

Canine mammary gland tumors (CMTs) are the most common and lethal cancers in female dogs. Dysregulated phosphoinositide 3-kinases (PI3K)/AKT pathway reportedly was involved in the growth and metastasis of CMTs. However, there are few studies on therapeutic strategies for targeting the PI3K pathway in CMTs. In this study, we aimed to determine whether palmatine, a natural isoquinoline alkaloid with anti-cancer properties, could inhibit the growth of CMTs and whether the inhibitory effect was mediated through the PI3K/AKT pathway. Our in vitro experiments on CMT-U27, a CMT cell line, showed that palmatine reduced cell proliferation and induced cell death. Western blotting results revealed that palmatine decreased the protein expression of PI3K, PTEN, AKT, and mechanistic target of rapamycin in the PI3K/AKT pathway, which was supported by the results of immunocytochemistry. Additionally, palmatine suppressed the migration and tube formation of canine aortic endothelial cells as well as the migration of CMT U27 cells. Our in vivo results showed that palmatine inhibited tumor growth in a CMT-U27 mouse xenograft model. We observed a decreased expression of proteins in the PI3K/AKT pathway in tumor tissues, similar to the in vitro results. Furthermore, palmatine significantly disrupted the tumor vasculature and inhibited metastasis to adjacent lymph nodes. In conclusion, our findings demonstrate that palmatine exerts anti-cancer effects against CMTs by inhibiting PI3K/AKT signaling pathway, suggesting that palmatine has potential as a canine-specific PI3K inhibitor for the treatment of CMTs.

Bisphenol A is more potent than bisphenol S in influencing the physiological and pathological functions of lungs via inducing lung fibrosis and stimulating metastasis.

Bisphenol A (BPA) is widely used in the production of plastics, food containers, and receipt ink globally. However, research has identified it as an endocrine disruptor, affecting the hormonal balance in living organisms. Bisphenol S (BPS), one of the alternative substances, was developed, but its effects on human health and the underlying mechanisms remain unclarified. Specifically, research on the effects of oral exposure to bisphenol on the lungs is lacking. We examined the potential differences in toxicity between these compounds in lung cells in vitro and in vivo. Our toxicity mechanism studies on MRC5 and A549 cells exposed to BPA or BPS revealed that BPA induced actin filament abnormalities and activated epithelial-mesenchymal transition (EMT). This finding suggests an increased potential for lung fibrosis and metastasis in lung cancer. However, given that BPS was not detected at the administered dose and under the specific experimental conditions, the probability of these occurrences is considered minimal. Additionally, animal experiments confirmed that oral exposure to BPA activates EMT in the lungs. Our study provides evidence that prolonged oral exposure to BPA can lead to EMT activation in lung tissue, similar to that observed in cell experiments, suggesting the potential to induce lung fibrosis. This research emphasizes the importance of regulating the use of BPA to mitigate its associated pulmonary toxicity. Furthermore, it is significant that within the parameters of our experimental conditions, BPS did not exhibit the toxicological pathways clearly evident in BPA.

Perfluorooctanoic acid (PFOA) and hexafluoropropylene oxide-dimer acid (GenX): Hepatic stress and bile acid metabolism with different pathways.

Per- and polyfluoroalkyl substances (PFASs) and perfluoroalkyl ether carboxylic acids (PFECAs) are organic chemicals that are widely used in the manufacture of a wide range of human-made products. Many monitoring findings revealed the presence of PFASs and PFECAs in numerous environmental sources, including water, soil, and air, which drew more attention to both chemicals. Because of their unknown toxicity, the discovery of PFASs and PFECAs in a variety of environmental sources was viewed as a cause for concern. In the present study, male mice were given orally one of the typical PFASs, perfluorooctanoic acid (PFOA), and one of the representative PFECAs, hexafluoropropylene oxide-dimer acid (HFPO-DA). The liver index showing hepatomegaly rose significantly after 90 d of exposure to PFOA and HFPO-DA, respectively. While sharing similar suppressor genes, both chemicals demonstrated unique hepatotoxic mechanisms. In different ways, these two substances altered the expression of hepatic stress-sensing genes as well as the regulation of nuclear receptors. Not only are bile acid metabolism-related genes in the liver altered, but cholesterol metabolism-related genes as well. These results indicate that PFOA and HFPO-DA both cause hepatotoxicity and bile acid metabolism impairment with distinct mechanisms.

Effectiveness of Paxlovid, an Oral Antiviral Drug, Against the Omicron BA.5 Variant in Korea: Severe Progression and Death Between July and November 2022.

BACKGROUND: Paxlovid is an oral antiviral drug that received emergency use authorization in South Korea for the treatment of patients with mild-to-moderate coronavirus disease 2019 (COVID-19) on January 14, 2022. Since the onset of the severe acute respiratory syndrome coronavirus 2 pandemic, the virus has continued to evolve. The emergence of new variants has raised concerns about possible reductions in the effectiveness of vaccines and drugs. The effectiveness of Paxlovid in patients infected with the omicron variant and subvariants has not yet been determined. This study assessed the effectiveness of Paxlovid at reducing the risk of severe/critical illness or death and death in patients with mild-to-moderate COVID-19 caused by omicron subvariant BA.5. METHODS: In this nationwide retrospective cohort study, data on 8,902,726 patients were collected from four sources (the Drug Utilization Review database, COVID-19 Patient Information Management System, confirmed patient information, and basic epidemiological investigation data) between July 1 and November 30, 2022. Multivariable logistic regression analysis was conducted, with adjustment for age, sex, severe acute respiratory syndrome coronavirus 2 immunity (vaccination), and comorbidities. RESULTS: A total of 1,936,925 patients with COVID-19 were included in the analysis, including 420,996 patients treated with Paxlovid, and 1,515,959 patients not treated with Paxlovid. Paxlovid treatment in patients aged ≥ 60 years of age was associated with significantly reduced risk of severe/critical illness or death (46.0%), and death rate (32.5%), and its effectiveness was high, regardless of vaccination status. CONCLUSION: Paxlovid is effective at reducing the risk of death due to COVID-19 in patients with omicron BA.5 infection, especially in older patients, regardless of vaccination status. This suggests that older patients with COVID-19-related symptoms should be administered Paxlovid, regardless of their vaccination status, to reduce severity and risk of death.

Obstructive Sleep Apnea Is Associated With Late-Onset Preeclampsia in Overweight Pregnant Women in Korea.

BACKGROUND: Obstructive sleep apnea (OSA) is closely related to maternal obesity in pregnant women, and the association increases with later pregnancy. Obesity and OSA are risk factors of pregnancy-related complications, including gestational hypertension, gestational diabetes mellitus (GDM), and fetal morbidities. We aimed to determine the prevalence of OSA and to assess the impact of OSA on pregnancy-related disorders in overweight pregnant women. METHODS: Eligible participants who were overweight [body mass index (BMI) ≥ 23 kg/m²] in gestational age 30 weeks or more, assessed OSA using a portable polysomnography at home. Clinical data were collected from pregnant women and their babies. RESULTS: The average age of 51 participants was 34.5 years (27-44 years). The number of primipara was 25 (49%) and that of multipara was 26 (51%). Eight cases of GDM (15.7%) and five cases of preeclampsia (9.8%) were reported, and six patients (11.8%) experienced preterm delivery. In results of polysomnography, 14 patients (27.5%) were diagnosed as OSA. Apnea-hypopnea index moderately correlated with BMI (r = 0.515, P < 0.001). The BMI (P < 0.005) and preeclampsia rate (P < 0.017) were higher in the OSA group compared to the control group. Odds ratios (ORs) adjusting age, BMI, parity, and abortion history were calculated. The presence of OSA increased OR of preeclampsia (OR, 13.1; 95% confidence interval, 1.1-171.3). The majority of preeclampsia patients (4/5, 80%) underwent preterm delivery. CONCLUSION: OSA is an important risk factor for preeclampsia, resulting in preterm delivery. For overweight pregnant women, an OSA evaluation should be mandatory.

The Multifaceted Clinical Characteristics of Congenital Cytomegalovirus Infection: From Pregnancy to Long-Term Outcomes.

BACKGROUND: The aim of this study was to capture multifaceted clinical characteristics of congenital cytomegalovirus (CMV) infection from diagnosis to treatment using a multidisciplinary approach including obstetrics, pediatrics, pathology, and otorhinolaryngology-head and neck surgery. METHODS: This is a retrospective study including 30 consecutive cases of congenital CMV infection that were diagnosed at a single tertiary hospital located in Seoul, Korea from January 2009 to December 2020. Congenital CMV infection was defined as a positive result by polymerase chain reaction from urine, saliva or cerebrospinal fluid or positive CMV IgM from neonatal blood sampled within 3 weeks after birth. All cases were analyzed with respect to whole clinical characteristics from diagnosis to treatment of congenital CMV by a multidisciplinary approach including prenatal sonographic findings, maternal immune status regarding CMV infection, detailed placental pathology, neonatal clinical manifestation, auditory brainstem response test, and antiviral treatment (ganciclovir or valganciclovir). Long-term outcomes including developmental delay and hearing loss were also investigated. RESULTS: The total number of births during the study period in our institution was 19,385, with the prevalence of congenital infection estimated to be 0.15%. Among 30 cases of congenital CMV, the median gestational age at delivery was 32.2 weeks [range, 22.6-40.0] and 66.7% of these infants were delivered preterm at less than 37 weeks. Suspected fetal growth restriction was the most common prenatal ultrasound finding (50%) followed by ventriculomegaly (17.9%) and abnormal placenta (17.9%), defined as thick placenta with calcification. No abnormal findings on ultrasound examination were observed in one-third of births. Maternal CMV serology tests were conducted in only 8 cases, and one case each of positive and equivocal IgM were found. The most common placental pathologic findings were chronic villitis (66.7%) and calcification (63.0%), whereas viral inclusions were identified in only 22.2%. The most common neonatal manifestations were jaundice (58.6%) followed by elevation of aspartate aminotransferase (55.2%) and thrombocytopenia (51.7%). After excluding cases for which long-term outcomes were unavailable due to death (n = 4) or subsequent follow up loss (n = 3), developmental delay was confirmed in 43.5% of infants (10/23), and hearing loss was confirmed in 42.9% (9/21) during the follow-up period. In our cohort, 56.7% (17/30) of neonates were treated for congenital CMV with ganciclovir or valganciclovir. CONCLUSION: Our data show that prenatal findings including maternal serologic tests and ultrasound have limited ability to detect congenital CMV in Korea. Given that CMV is associated with high rates of developmental delay and hearing loss in infants, there is an urgent need to develop specific strategies for the definite diagnosis of congenital CMV infection during the perinatal period by a multidisciplinary approach to decrease the risks of neurologic impairment and hearing loss through early antiviral treatment.

The Distinctive Permutated Domain Structure of Periplasmic α-Amylase (MalS) from Glycoside Hydrolase Family 13 Subfamily 19.

Periplasmic α-amylase MalS (EC. 3.2.1.1), which belongs to glycoside hydrolase (GH) family 13 subfamily 19, is an integral component of the maltose utilization pathway in Escherichia coli K12 and used among Ecnterobacteriaceae for the effective utilization of maltodextrin. We present the crystal structure of MalS from E. coli and reveal that it has unique structural features of circularly permutated domains and a possible CBM69. The conventional C-domain of amylase consists of amino acids 120-180 (N-terminal) and 646-676 (C-terminal) in MalS, and the whole domain architecture shows the complete circular permutation of C-A-B-A-C in domain order. Regarding substrate interaction, the enzyme has a 6-glucosyl unit pocket binding it to the non-reducing end of the cleavage site. Our study found that residues D385 and F367 play important roles in the preference of MalS for maltohexaose as an initial product. At the active site of MalS, ß-CD binds more weakly than the linear substrate, possibly due to the positioning of A402. MalS has two Ca2+ binding sites that contribute significantly to the thermostability of the enzyme. Intriguingly, the study found that MalS exhibits a high binding affinity for polysaccharides such as glycogen and amylopectin. The N domain, of which the electron density map was not observed, was predicted to be CBM69 by AlphaFold2 and might have a binding site for the polysaccharides. Structural analysis of MalS provides new insight into the structure-evolution relationship in GH13 subfamily 19 enzymes and a molecular basis for understanding the details of catalytic function and substrate binding of MalS.

Small sessile serrated polyps might not be at a higher risk for future advanced neoplasia than low-risk adenomas or polyp-free groups.

BACKGROUND: Polypectomy surveillance colonoscopy is recommended according to the risk stratification of initially removed polyps. This study aimed to evaluate the risk of advanced neoplasia following low-risk SSPs compared with that following LRAs and polyp-free groups. MATERIALS AND METHODS: From September 2013 to August 2017, asymptomatic Koreans aged 50-75 years who underwent surveillance colonoscopy post-baseline colonoscopy were enrolled. The 1314 participants who met the study design criteria were stratified into three groups according to the presence of LRAs or low-risk SSPs. The rate of advanced neoplasia was then compared between groups by surveillance colonoscopy. RESULTS: A total of 1314 participants were classified according to baseline colonoscopy findings: no polyp (n = 551), LRA (n = 707), and low-risk SSP (n = 56). All participants underwent surveillance colonoscopy after an average of 28.1 ± 8.7 months. The rate of advanced neoplasia at surveillance was not different between groups: no polyp group (13/551, 2.4%), LRA group (27/707, 3.8%), and low-risk SSP group (0/56, 0%). The LRA group exhibited a significantly higher rate of low- and high-risk polyps (47.5, 13.4%) than did the no polyp (35.6, 7.4%, p < .001, p = .001), but no significant differences to the low-risk SSP group (35.7, 7.1%, p = .117, p = .253), respectively. CONCLUSIONS: Patients with low-risk SSPs were not at a higher risk of advanced neoplasia than LRA patients, even in the polyp-free group. We suggest that surveillance colonoscopy after the removal of low-risk SSPs is not required more often than for LRAs.

Trends in clinical outcomes and long-term survival after robotic gastrectomy for gastric cancer: a single high-volume center experience of consecutive 2000 patients.

BACKGROUND: Minimally invasive surgery is now a standard treatment for gastric cancer. Many retrospective studies have reported that robotic gastrectomy is safe and feasible, with similar short- and long-term outcomes as laparoscopic gastrectomy. However, no studies have reported the details of surgical and survival outcomes for robotic gastrectomy. This study aimed to evaluate the surgical trends and techniques of robotic gastrectomy and analyze the surgical outcomes of 2000 consecutive patients with gastric cancer who underwent robotic gastrectomy over 14 years. METHODS: Between July 2005 and January 2019, 2000 consecutive robotic gastrectomies were performed. We evaluated short- and long-term outcomes as well as surgical trends after robotic gastrectomy. RESULTS: There were 1,560 subtotal gastrectomies (78%), 324 total gastrectomies (16.2%), 83 proximal gastrectomies (4.2%), and 33 completion total gastrectomies (1.7%). The rates of major complications and mortality were 3.1% and 0.3%, respectively. In a subgroup analysis, there were no significant differences in the rate of complications over time (P = 0.696). Five-year overall survival rates were 97.6% for stage I, 91.9% for stage II, and 69.2% for stage III, with a total recurrence rate of 5.3%. Since its adoption in 2005, the proportion of robotic gastrectomies, as well as technically demanding procedures have increased over time. CONCLUSIONS: Our 14 years' experience of 2000 robotic gastrectomies has shown the proportion, as well as the number of robotic gastrectomies, have tended to increase and trends toward to technically demanding procedures. Outcomes of robotic gastrectomy appear safe and feasible with acceptable short- and long-term outcomes.

Fluorescent lymphography during minimally invasive total gastrectomy for gastric cancer: an effective technique for splenic hilar lymph node dissection.

BACKGROUND: Fluorescent lymphography is an excellent technique for complete lymph node dissection during minimally invasive surgery for gastric cancer. This study aimed to evaluate the role of fluorescent lymphography in splenic hilar lymph node dissection during minimally invasive total gastrectomy. METHODS: We retrospectively analyzed 168 gastric cancer patients who underwent minimally invasive total gastrectomy with D2 + No. 10 lymph node dissection from 2013 to 2018. Fluorescent lymphography was used whenever it is possible. However, when near-infrared imaging system and endoscopic indocyanine green injection were not available, we performed surgery without fluorescent lymphography. A total of 74 patients underwent surgery with fluorescent lymphography (FL group) and 94 underwent surgery without it (non-FL group). Perioperative and long-term outcomes including the number of retrieved lymph nodes at each nodal station were compared between groups. RESULTS: The median number of retrieved lymph nodes at the splenic hilum was larger in the FL group {2.5 [Interquartile range (IQR), 1-5]} than in the non-FL group [1 (IQR, 1-3); P = 0.012]. The negative predictive value of fluorescent lymphography for lymph node metastasis at the splenic hilum was 97.1%, although the sensitivity was 66.7%. The overall survival (FL: 96.9% vs. non-FL: 88.9%; P = 0.334) and relapse-free survival (FL: 90.5% vs. non-FL: 65.5%; P = 0.054) were higher in the FL group, although there were no statistical differences. However, among the patients without lymph node metastasis, the relapse-free survival was significantly higher in the FL group (100%) than in the non-FL group (67.1%; P = 0.017). CONCLUSIONS: Fluorescent lymphography is an effective tool for complete lymph node dissection at the splenic hilum. Moreover, it may help select patients who do not need splenic hilar lymph node dissection during a total gastrectomy.