Crystal structure of mango α1,3/α1,4-fucosyltransferase elucidates unique elements that regulate Lewis A-dominant oligosaccharide assembly

In various organisms, α1,3/α1,4-fucosyltransferases (CAZy GT10 family enzymes) mediate the assembly of type I (Galβ1,3GlcNAc) and/or type II (Galβ1,4GlcNAc)-based Lewis structures that are widely distributed in glycoconjugates. Unlike enzymes of other species, plant orthologues show little fucosyltransferase activity for type II-based glycans and predominantly catalyze the assembly of the Lewis A structure [Galβ1,3(Fucα1,4)GlcNAc] on the type I disaccharide unit of their substrates. However, the structural basis underlying this unique substrate selectivity remains elusive. In this study, we investigated the structure-function relationship of MiFUT13A, a mango α1,3/α1,4-fucosyltransferase. The prepared MiFUT13A displayed distinct α1,4-fucosyltransferase activity. Consistent with the enzymatic properties of this molecule, X-ray crystallography revealed that this enzyme has a typical GT-B fold-type structure containing a set of residues that are responsible for its SN2-like catalysis. Site-directed mutagenesis and molecular docking analyses proposed a rational binding mechanism for type I oligosaccharides. Within the catalytic cleft, the pocket surrounding Trp121 serves as a binding site, anchoring the non-reducing terminal β1,3-galactose that belongs to the type I disaccharide unit. Furthermore, Glu177 was postulated to function as a general base catalyst through its interaction with the 4-hydroxy group of the acceptor N-acetylglucosamine residue. Adjacent residues, specifically Thr120, Thr157 and Asp175 were speculated to assist in binding of the reducing terminal residues. Intriguingly, these structural elements were not fully conserved in mammalian orthologue which also shows predominant α1,4-fucosyltransferase activity. In conclusion, we have proposed that MiFUT13A generates the Lewis A structure on type I glycans through a distinct mechanism, divergent from that of mammalian enzymes.

Usefulness of endoscopic ultrasound-guided transhepatic biliary drainage with a 22-gauge fine-needle aspiration needle and 0.018-inch guidewire in the procedure's induction phase

Endoscopic ultrasound (EUS)-guided transhepatic biliary drainage is usually performed with a 19-gauge fine-needle aspiration (FNA) needle and a 0.025-inch guidewire. The combination of a 22-gauge FNA needle and a 0.018-inch guidewire is reported to be effective as a rescue option when the bile duct diameter is small or technically challenging. Experts in EUS-guided transhepatic biliary drainage have reported that bile duct puncture with a 19-gauge FNA needle is possible in most cases, but is not easy to reproduce by endoscopists with less experience in EUS-guided transhepatic biliary drainage. We investigated the usefulness of EUS-guided transhepatic biliary drainage using a 22-gauge FNA needle and a 0.018-inch guidewire during the procedure's induction phase. Consecutive patients who underwent EUS-guided transhepatic biliary drainage at our institution from March 2021 to May 2023 were evaluated, and 37 were included. Biliary drainage was performed for malignant bile duct stricture in 36 patients and choledocholithiasis in one patient. The median target bile duct diameter was 4.5 mm (2.5-9.4). Biliary access, fistula dilation, and stent placement were successful in the 37 patients (100%). The median procedure time was 35 min (16-125). Adverse events occurred in four (10.8%) patients. EUS-guided transhepatic biliary drainage using a 22-gauge FNA needle and a 0.018-inch guidewire is a useful and promising option for endoscopists with limited experience in EUS-guided transhepatic biliary drainage in the procedure's induction phase.

Medical radiation exposure during gastrointestinal enteral metallic stent placement: Post hoc analysis of the REX-GI study

Background and Aim

Recently, the use of various endoscopic procedures performed under X-ray fluoroscopy guidance has increased. With the popularization of such procedures, diagnostic reference levels (DRLs) have been widely accepted as the global standard for various procedures with ionizing radiation. The Radiation Exposure from Gastrointestinal Fluoroscopic Procedures (REX-GI) study aimed to prospectively collect actual radiation exposure (RE) data and establish DRLs in gastrointestinal endoscopy units. In this post hoc analysis of the REX-GI study, we established DRLs for each disease site by analyzing cases of gastrointestinal enteral metallic stent placement.

Methods

The REX-GI study was a multicenter, prospective observational study conducted to collect actual RE data during gastrointestinal enteral metallic stent placement. To establish DRL values for three disease sites, namely the esophagus, gastroduodenum, and colon, we examined fluoroscopy time (FT; min), number of X-ray images, air kerma at the patient entrance reference point (K a,r; mGy), and the air kerma-area product (P KA; Gy cm2) during enteral metallic stent placement.

Results

Five-hundred and twenty-three stenting procedures were performed. The DRL values of FT (min) and the number of X-ray images for the esophagus/gastroduodenum/colon were 9/16/18 min and 9/15/11 min, respectively. Furthermore, the DRL values of K a,r and P KA for each disease site were 43.3/120/124 mGy and 10.3/36.6/48.4 Gy cm2, respectively. Among the procedures, esophageal stents were significantly associated with the lowest values (P < 0.001).

Conclusion

The characteristics of RE vary according to disease site among gastrointestinal enteral metallic stent placements. Thus, it is desirable to set DRL values based on the disease site.

Microscopic evidence of sandstone deterioration and damage by fungi isolated from the Angkor monuments in simulation experiments

The Angkor monuments have been registered on the World Cultural Heritage List of UNESCO, while the buildings built mostly of sandstone are suffering from serious deterioration and damage. Microorganisms are one of the leading causes for the sandstone deterioration. Identification of the mechanisms underlying the biodeterioration is of significance because it reveals the biochemical reaction involved so that effective conservation and restoration of cultural properties can be achieved. In this study, the fungal colonization and biodeterioration of sandstone in simulation experiments were examined using confocal reflection microscopy (CRM) and scanning electron microscopy-energy dispersive X-ray spectroscopy (SEM-EDS). Aspergillus sp. strain AW1 and Paecilomyces sp. strain BY8 isolated from the deteriorated sandstone of Angkor Wat and Bayon of Angkor Thom, respectively, were inoculated and incubated with the sandstone used for construction of Angkor Wat. With CRM, we could visualize that strain AW1 tightly attached to and broke in the sandstone with extension of the hyphae. Quantitative imaging analyses showed that the sandstone surface roughness increased and the cavities formed under the fungal hyphae deepened during the incubation of strains AW1 and BY8. These highlighted that the massive growth of fungi even under the culture conditions was associated with the cavity formation of the sandstone and its expansion. Furthermore, SEM-EDS indicated the flat and Si-rich materials, presumably quartz and feldspar, were found frequently at the intact sandstone surface. But the flatness was lost during the incubation, possibly due to the detachment of the Si-rich mineral particles by the fungal deterioration. Consequently, this study proposed a biodeterioration model of the sandstone in that the hyphae of fungi elongated on the surface of the sandstone to penetrate into the soft and porous sandstone matrix, damaging the matrix and gradually destabilize the hard and Si-rich minerals, such as quartz and feldspar, to the collapse and cavities.

Initial experience of transpapillary gallbladder biopsy using newly designed device delivery system

Transpapillary gallbladder biopsy has been reported for the diagnosis of gallbladder disease, and this procedure requires special biopsy forceps or a large-diameter pusher catheter. We retrospectively examined consecutive patients who underwent transpapillary gallbladder biopsy using a newly designed device delivery system (Endosheather; Piolax Medical Device, Kanagawa, Japan). We evaluated 11 patients (median age, 71 years [28-85]) who underwent transpapillary gallbladder biopsy from June 2021 to July 2022. The selective gallbladder cannulation and delivery system insertion success rate was 90.9% (10/11). The target lesion biopsy success rate was 63.6% (7/11). The biopsy time (i.e., time to completion of biopsy after successful guidewire placement) was 8.7 (5.4-32.7) min. In 1 patient in whom all 6 gallbladder bile juice cytology results were benign, the biopsy result was suspicious of adenocarcinoma. The final diagnosis for this patient was gallbladder cancer. Adverse events occurred in 2 patients. In 1 patient, acute cholecystitis occurred and required emergency surgery. Transpapillary gallbladder biopsy using the Endosheather is a potential option for the diagnosis of gallbladder disease. A good indication for this technique is considered to be wall thickening at the gallbladder fundus, where it is difficult to differentiate between benign and malignant lesions by imaging modalities such as ultrasonography or endoscopic ultrasound. The addition of transpapillary gallbladder biopsy may be advantageous when performing bile juice cytology using a nasogallbladder drainage tube for the diagnosis of gallbladder disease.

Case of needle tract seeding during preoperative neoadjuvant chemotherapy for resectable pancreatic cancer

Reports of needle tract seeding (NTS) as a complication of endoscopic ultrasound‐guided fine‐needle aspiration (EUS‐FNA) have been increasing. To date, most of the reported cases of NTS have been diagnosed during the postoperative follow‐up period. Herein, we report a case of NTS that occurred during preoperative neoadjuvant chemotherapy after EUS‐FNA for resectable pancreatic cancer. The patient underwent transgastric EUS‐FNA for a pancreatic tail tumor. He was diagnosed as having resectable pancreatic cancer and received preoperative neoadjuvant chemotherapy. After completion of the chemotherapy, computed tomography showed a thick‐walled cyst‐like structure appearing between the pancreas and the gastric wall. Combined resection revealed adenocarcinoma invasion into the cyst‐like structure. Based on the clinical course, and surgical and pathological findings, the condition was diagnosed as NTS. It is thus crucial that after EUS‐FNA, a detailed review of the imaging findings be conducted in the preoperative period. If adhesions between the stomach and the pancreas are observed after transgastric EUS‐FNA, combined resection of the gastric wall should be considered.

Localized Rectal Amyloidosis with Morphologic Changes from the Submucosal Tumor to the Ulcerative Lesion That Led to Hematochezia During Observation

A 75-year-old woman visited our hospital with constipation. Colonoscopy revealed a submucosal tumor in the rectum. She was followed up as a case of mucosal prolapse syndrome. Six years later, she was referred to our hospital due to hematochezia and abdominal pain. Colonoscopy revealed that the submucosal tumor had an ulcerative appearance with bleeding. Low anterior resection was performed. Amyloid protein deposition was detected from the submucosa to subserosa. Other organs showed no evidence of amyloidosis; we therefore diagnosed the patient with localized rectal amyloidosis. This is a rare case of symptomatic localized rectal amyloidosis whose long-term progression was able to be endoscopically observed.

Endoscopic Nasobiliary Drainage Comparable with Endoscopic Biliary Stenting as a Preoperative Drainage Method for Malignant Hilar Biliary Obstruction: A Multicenter Retrospective Study

INTRODUCTION

Preoperative endoscopic biliary drainage (PEBD) for malignant hilar biliary obstruction (MHBO) is widely accepted. Recent PEBD consists of endoscopic nasobiliary drainage (ENBD), conventional endoscopic biliary stenting (CEBS) with plastic stents across the papilla, and endoscopic biliary inside stenting (EBIS) with plastic stents above the papilla, while ENBD is the primary procedure in Asian countries. Thus, we aimed to compare the efficacy of ENBD with those of CEBS and EBIS as a means of PEBD for MHBO.

METHODS

We retrospectively identified patients with MHBO who underwent upfront surgery between January 2011 and December 2018 in a multicenter setting. The outcome measures were cumulative dysfunction of PEBD, risk factors for PEBD dysfunction, and adverse events.

RESULTS

We analyzed a total of 219 patients, comprising 163 males (74.4%); mean age, 69.7 (±7.6) years; Bismuth-Corlette (BC) classification I, II, IIIa, IIIb, and IV in 68, 49, 43, 30, and 29 patients, respectively; and diagnosis of hilar cholangiocarcinoma and gallbladder cancer in 188 and 31 patients, respectively. PEBD procedures were performed in 160 patients with ENBD, 31 patients with CEBS, and 28 patients with EBIS. PEBD dysfunction occurred in 58 patients (26.5%), and the cumulative dysfunction rates were not significantly different among PEBD methods (p = 0.60). Multivariate analysis showed that BC-IV was significantly associated with the occurrence of PEBD dysfunction (hazard ratio = 2.10, p = 0.02). The adverse event rates were not significantly different among PEBD groups (p = 0.70).

CONCLUSION

ENBD as a means of PEBD for MHBO is comparable with CEBS and EBIS in rates of dysfunction and adverse events.

Laparoscopic gastrojejunostomy to manage gastric outlet obstruction associated with endoscopic submucosal dissection of large gastric epithelial neoplasms: A two‐case report

We report on two patients with stasis symptoms, including vomiting and nausea that were caused by deformity, stenosis, and decreased gastric peristalsis associated with artificial ulcers after endoscopic submucosal dissection (ESD). In both cases, the symptoms remained unresolved despite repetitive endoscopic balloon dilation (EBD). Therefore, laparoscopic gastrojejunostomy was performed. Soon after the procedure, their food intake was improved. Laparoscopic gastrojejunostomy can be an option for the treatment of gastric outlet obstruction induced by a large field of gastric ESD that is refractory to EBD.

Diagnostic Reference Levels for Fluoroscopy-guided Gastrointestinal Procedures in Japan from the REX-GI Study: A Nationwide Multicentre Prospective Observational Study

BACKGROUND

Diagnostic reference levels (DRLs) are required to optimize medical exposure. However, data on DRLs for interventional fluoroscopic procedures are lacking, especially in gastroenterology. This study aimed to prospectively collect currently used radiation doses and help establish national DRLs for fluoroscopy-guided gastrointestinal procedures in Japan.

METHODS

This multicentre, prospective, observational study collected actual radiation dose data from endoscopic retrograde cholangiopancreatography (ERCP), interventional endoscopic ultrasound (EUS), balloon-assisted enteroscopy (BAE), enteral metallic stent placement, and enteral tube placement from May 2019 to December 2020. The study outcomes were fluoroscopy time (FT: min), air kerma at the patient entrance reference point (Ka,r: mGy), air kerma area product (PKA: Gycm2), and radiation dose rate (RDR: mGy/min). Additionally, the basic settings of fluoroscopy equipment and the factors related to each procedure were investigated. This study was registered in the UMIN Clinical Trial Registry (UMIN 000036525).

FINDINGS

Overall, 12959 fluoroscopy-guided gastrointestinal procedures were included from 23 hospitals in Japan. For 11162 ERCPs, the median/third quartile values of Ka,r (mGy), PKA (Gycm2), and FT (min) were 69/145 mGy, 16/32 Gycm2, and 11/20 min, respectively. Similarly, these values were 106/219 mGy, 23/41 Gycm2 and 17/27 min for 374 interventional EUSs; 53/104 mGy, 16/32 Gycm2 and 10/15 min for 523 metallic stents; 56/104 mGy, 28/47 Gycm2, and 12/18 min for 599 tube placements; and 35/81 mGy, 16/43 Gycm2 and 7/15 min for 301 BAEs, respectively. For the overall radiation dose rate, the median/third quartile values of RDR were 5.9/9.4 (mGy/min). The RDR values at each institution varied widely.

INTERPRETATION

This study reports the current radiation doses of fluoroscopy-guided gastrointestinal procedures expressed as DRL quantities. This will serve as a valuable reference for national DRL values.

FUNDING

This work was supported by a clinical research grant from the Japanese Society of Gastroenterology.

Does second-look endoscopy reduce the bleeding after gastric endoscopic submucosal dissection for patients receiving antithrombotic therapy?

Background

In patients with average risk of bleeding, second-look endoscopy does not reportedly reduce bleeding after gastric endoscopic submucosal dissection. However, effectiveness of second-look endoscopy for patients with a high risk of bleeding, such as those who are taking antithrombotic agents, is unclear. Hence, this study aims to clarify the effectiveness of second-look endoscopy for patients with antithrombotic therapy.

Methods

We studied 142 consecutive patients with 173 gastric epithelial neoplasms who were routinely taking antithrombotic agents and were treated by endoscopic submucosal dissection at Tonan Hospital between November 2013 and December 2019. They were classified into two groups: those with second-look endoscopy (SLE group, 69 patients with 85 lesions) and those without second-look endoscopy (non-SLE group, 73 patients with 88 lesions). The incidence of post-endoscopic submucosal dissection bleeding was compared between the SLE and non-SLE groups.

Results

There were no statistical differences in the rate of patients undergoing single antiplatelet therapy, single anticoagulant therapy, and multiple therapy between the SLE and non-SLE groups (SLE group vs. non-SLE group; 32 [46.4%], 16 [23.2%], and 21 [30.4%] patients vs. 37 [50.7%], 20 [27.4%], and 16 [21.9%] patients, respectively; p = 0.50). Post-endoscopic submucosal dissection bleeding incidence was 21.7% (15/69) and 21.9% (16/73) in the SLE and non-SLE groups, respectively, and did not significantly differ between the two groups (p = 0.98).

Conclusions

For patients taking antithrombotic agents, the incidence of post-endoscopic submucosal dissection bleeding was not reduced by second-look endoscopy.

A case of hypereosinophilia with digital ischaemia successfully treated with intravenous prostaglandin E1

In the therapeutic management of eosinophilic disorder, it is important to prevent hypereosinophilia (HE)-related organ damage even in the process of diagnosis. We describe here a unique clinical and histopathological findings of the patient with HE accompanied with digital ischaemia. Treatment with intravenous prostaglandin E1 was essential for digital ischaemia in our case while benralizumab, humanized monoclonal antibody against interleukin-5 receptorα, did not affect. Our case suggests an earlier intervention for digital ischaemia in the therapeutic management of eosiniphilic disorder.

Comparison of clinicopathological features and long-term prognosis between mixed predominantly differentiated-type and pure differentiated-type early gastric cancer

Background

Recent studies have shown that mixed predominantly differentiated-type (MD) early gastric cancer (EGC) might have more malignant potential than pure differentiated-type (PD) EGC. However, no study has analyzed all differentiated-type EGC cases treated endoscopically and surgically. This study aimed to compare the differences in clinicopathological features and long-term prognosis between MD- and PD-EGC.

Methods

We evaluated all patients with differentiated-type EGCs who were treated endoscopically and surgically in our hospital between January 2010 and October 2014. The clinicopathological features and long-term prognosis of MD-EGC were compared with those of PD-EGC.

Results

A total of 459 patients with 459 lesions were evaluated in this study; of them, 409 (89.1%) and 50 (10.9%) were classified into the PD and MD groups, respectively. Submucosal invasion was found in 96 (23.5%) patients of the PD group and in 33 (66.0%) patients of the MD group (p < 0.01). The rates of positive lymphatic and vascular invasion and ulceration were significantly higher in the MD group than in the PD group (p < 0.01). The proportion of patients with lymph node metastasis was also significantly higher in the MD group than in the PD group (5 (10%) vs 6 (1.5%), p < 0.01). The 5-year overall and EGC-specific survival rates in the PD group were 88.3 and 99.5%, respectively, while they were 94.0 and 98.0% in the MD group, respectively.

Conclusions

MD-EGC has more malignant potential than PD-EGC. However, the long-term prognosis of MD-EGC is good and is not significantly different from that of PD-EGC when treated appropriately.

Direct comparison of bacterial communities in soils contaminated with different levels of radioactive cesium from the first Fukushima nuclear power plant accident

The Great East Japan Earthquake caused a serious accident at the first Fukushima nuclear power plant (NPP), which in turn released a large amount of radionuclides. Little attention has been paid to in-situ soil microorganisms exposed to radioactive contamination by the actual NPP accident. We herein investigated bacterial communities in the radioactive cesium (Cs)-contaminated and non-contaminated soils by high-throughput sequencing. The uppermost and ectorhizosphere soil samples were collected from the base of mugwort grown in the same soil type with the same soil-use history in order to compare the bacterial communities at geographically separated areas. The concentrations of radioactive Cs in the soils ranged from 10 to 563,000 Bq ¹³⁷Cs/kg dry soil, with the highest concentration being detected at 1 km from the NPP. Alpha-diversity indices, i.e., Chao1, Shannon and Simpson reciprocal, of the sequence data showed the lower bacterial diversity in the most highly Cs-contaminated soil. Principal coordinate analysis with principle components 1 and 3 based on unweighted UniFrac distances indicated the significant difference in bacterial communities of the most contaminated area from those of the other areas. Operational taxonomic unit-based assay revealed higher abundance of the radio-resistant Geodermatophilus bullaregiensis relative in the most contaminated soil. Thus, it was strongly suggested that the radioactive accident facilitated the growth and/or survival of radio-resistant bacteria in the Cs-contaminated soils. The results of this study show that information on the soil type, vegetation and soil-use history enhances the direct comparison of geographically distant soil bacterial communities exposed to different levels of radioactive contamination.

True significance of N-acetylglucosaminyltransferases GnT-III, V and α1,6 fucosyltransferase in epithelial-mesenchymal transition and cancer

It is well known that numerous cancer-related changes occur in glycans that are attached to glycoproteins, glycolipids and proteoglycans on the cell surface and these changes in structure and the expression of the glycans are largely regulated by glycosyl-transferases, glycosidases, nucleotide sugars and their related genes. Such structural changes in glycans on cell surface proteins may accelerate the progression, invasion and metastasis of cancer cells. Among the over 200 known glycosyltransferases and related genes, β 1,6 N-acetylglucosaminyltransferase V (GnT-V) (the MGAT5 gene) and α 1,6 fucosyltransferase (FUT8) (the FUT8 gene) are representative enzymes in this respect because changes in glycans caused by these genes appear to be related to cancer metastasis and invasion in vitro as well as in vivo, and a number of reports on these genes in related to epithelial-mesenchymal transition (EMT) have also appeared. Another enzyme, one of the N-glycan branching enzymes, β1,4 N-acetylglucosaminyltransferase III (GnT-III) (the MGAT3 gene) has been reported to suppress EMT. However, there are intermediate states between EMT and mesenchymal-epithelial transition (MET) and some of these genes have been implicated in both EMT and MET and are also probably in an intermediate state. Therefore, it would be difficult to clearly define which specific glycosyltransferase is involved in EMT or MET or an intermediate state. The significance of EMT and N-glycan branching glycosyltransferases needs to be reconsidered and the inhibition of their corresponding genes would also be desirable in therapeutics. This review mainly focuses on GnT-III, GnT-V and FUT8, major players as N-glycan branching enzymes in cancer in relation to EMT programs, and also discusses the catalytic mechanisms of GnT-V and FUT8 whose crystal structures have now been obtained.

Non-negligible rate of needle tract seeding after endoscopic ultrasound-guided fine-needle aspiration for patients undergoing distal pancreatectomy for pancreatic cancer

BACKGROUND AND AIMS

Needle tract seeding after preoperative endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) for pancreatic body and tail cancer has been reported. This study aimed to investigate the long-term outcomes, including the needle tract seeding ratio, of patients undergoing distal pancreatectomy for pancreatic body and tail cancer diagnosed preoperatively by EUS-FNA.

METHODS

This retrospective, observational cohort study assessed patients from three university hospitals and 11 tertiary referral centers. All patients who underwent distal pancreatectomy for invasive cancer of the pancreatic body and tail between January 2006 and December 2015 were identified and reviewed. Needle tract seeding rate, recurrence-free survival (RFS), and overall survival (OS) were evaluated.

RESULTS

Of the 301 total patients analyzed, 176 underwent preoperative EUS-FNA (EUS-FNA group) and 125 did not (non-EUS-FNA group). The median follow-up periods of the EUS-FNA group and non-EUS-FNA group were 32.8 and 30.1 months. Six patients (3.4%) in the EUS-FNA group were diagnosed as having needle tract seeding. The 5-year cumulative needle tract seeding rate estimated using Fine and Gray's method was 3.8% (95% CI 1.6-7.8%). The median RFS or OS was not significantly different between the EUS-FNA group and the non-EUS-FNA group (23.7 vs 16.9 months: P = 0.205; 48.0 vs 43.9 months: P = 0.392).

CONCLUSION

Although preoperative EUS-FNA for pancreatic body and tail cancer has no negative effect on RFS or OS, needle tract seeding after EUS-FNA was observed to have a non-negligible rate. (UMIN000030719).

Association of second surveillance colonoscopy findings with index and first surveillance colonoscopy results

OBJECTIVE

Although there have been established guidelines for first surveillance colonoscopy (FSC) after a polypectomy, there is no consensus on performing a second surveillance colonoscopy (SSC), especially in Asian countries. This study aimed to investigate the association of SSC findings with index total colonoscopy (TCS) and FSC results.

METHODS

This was a single-center retrospective cohort study involving 1928 consecutive Japanese patients who had received three or more colonoscopies. High-risk colonoscopic findings were defined as advanced adenoma (≥10 mm in size, with a villous histology or high-grade dysplasia) or more than three adenomas, whereas low-risk findings were defined as one to two non-advanced adenomas. On the basis of index TCS results, the patients were divided into three groups: no adenomas (NA) (n = 888), low-risk (LR) (n = 476), and high-risk (HR) (n = 564) groups, respectively.

RESULTS

In the NA group, the rate of high-risk findings on SSC was significantly higher in patients with high-risk or low-risk findings on FSC than in those with no adenoma (7.7% and 7.9% vs 2.2%, P < 0.05). Patients in the LR and HR groups with high-risk findings on FSC had a significantly higher risk on SSC than those with low-risk findings or no adenoma on FSC (LR group: 28.6%, 9.4%, and 5.9%, respectively, P < 0.01; HR group: 34.5%, 18.8%, and 7.9%, respectively, P < 0.01).

CONCLUSIONS

Index TCS and especially FSC findings were predictive of SSC results. The study results may be useful for determining appropriate intervals for surveillance colonoscopy in Asian countries.

Inutility of endoscopic sphincterotomy to prevent pancreatitis after biliary metal stent placement in the patients without pancreatic duct obstruction

Background: The incidence of post-ERCP pancreatitis (PEP) has been reported to be significantly higher in patients without main pancreatic duct (MPD) obstruction who undergo transpapillary biliary metal stent (MS) placement than in those with ordinary ERCP setting.Objective: To evaluate the benefit of endoscopic sphincterotomy (ES) prior to MS placement in preventing PEP in patients with distal malignant biliary obstruction (MBO) without MPD obstruction.Materials and methods: In total, 160 patients who underwent initial MS placement for MBO were enrolled. Eighty-two patients underwent ES immediately prior to MS placement, whereas 78 underwent MS placement without ES. An inverse probability of treatment weighting method was adopted to adjust the differences of the patients' characteristics. The primary outcome was the incidence of PEP. The secondary outcomes included the incidence of other adverse events (bleeding, cholangitis, perforation and stent dislocation) and time to recurrent biliary obstruction.Results: The incidence of PEP was 26.8% in the ES and 23.1% in the non-ES (unadjusted odds ratio [OR] [95%CI]: 1.22, [0.60-2.51], adjusted OR [95%CI]: 1.23, [0.53-2.81], p = .63). Logistic-regression analysis revealed no factors that could be attributed to the occurrence of PEP. The incidence of other adverse events was not different between the groups. The median time to recurrent biliary obstruction was 131 (2-465) days and 200 (4-864) days in the ES and non-ES, respectively (p = .215).Conclusions: ES prior to MS placement for patients with distal MBO without MPD obstruction does not reduce the incidence of PEP.

Multicentre prospective observational study protocol for radiation exposure from gastrointestinal fluoroscopic procedures (REX-GI study)

INTRODUCTION

Recently, the use of various endoscopic procedures under X-ray fluoroscopic guidance, such as endoscopic retrograde cholangiopancreatography (ERCP), interventional endoscopic ultrasonography (EUS), enteral endoscopy and stenting, has been rapidly increasing because of the minimally invasive nature of these procedures compared with that of surgical intervention. With the spread of CT and fluoroscopic interventions, including endoscopic procedures under X-ray guidance, high levels of radiation exposure (RE) from medical imaging have led to major concerns throughout society. However, information about RE related to these image-guided procedures in gastrointestinal endoscopy is scarce, and the RE reference levels have not been established. The aim of this study is to prospectively collect the actual RE dose and to help establish diagnostic reference levels (DRLs) in the field of gastroenterology in Japan.

METHODS AND ANALYSIS

This is a multicentre, prospective observational study that is being conducted to collect the actual RE from treatments and diagnostic procedures, including ERCP, interventional EUS, balloon-assisted enteroscopy, enteral metallic stent placement and enteral tube placement. We will measure the total fluoroscopy time (min), the total dose-area product (Gycm2) and air-kerma (mGy) of those procedures. Because we are collecting the actual RE data and identifying the influential factors through a prospective, nationwide design, this study will provide guidance regarding the DRLs of ERCP, interventional EUS, balloon-assisted enteroscopy, enteral metallic stent placement and enteral tube placement.

ETHICS AND DISSEMINATION

Approval was obtained from the Institutional Review Board of Toyonaka Municipal Hospital (25 April 2019). The need for informed consent will be waived via the opt-out method of each hospital website.

TRIAL REGISTRATION NUMBER

The UMIN Clinical Trials Registry, UMIN000036525.

Endocuff-Assisted versus Cap-Assisted Colonoscopy Performed by Trainees: A Retrospective Study

Background/Aims

The adenoma detection rate (ADR) of screening colonoscopies performed by trainees is often lower than that of colonoscopies performed by experts. The effcacy of cap-assisted colonoscopy (CAC) in adenoma detection is well documented, especially that of CACs performed by trainees. Endocuff, a new endoscopic cap, is reportedly useful for adenoma detection; however, no trials have compared the effcacy of Endocuff-assisted colonoscopy (EAC) and CAC conducted by trainees. Therefore, the present study retrospectively compared the effcacy between EAC and CAC in trainees.

Methods

This was a single-center, retrospective study involving 305 patients who underwent either EAC or CAC performed by three trainees between January and December 2018. We evaluated the ADR, mean number of adenomas detected per patient (MAP), cecal intubation rate, cecal intubation time, and occurrence of complications between the EAC and CAC groups.

Results

The ADR was significantly higher in the EAC group than in the CAC group (54.3% vs. 37.3%, p=0.019), as was the MAP (1.36 vs. 0.74, p=0.003). No significant differences were found between the groups with respect to the cecal intubation rate or cecal intubation time. No major complications occurred in either group.

Conclusions

Our results suggest that EAC exhibits increased ADR and MAP compared to CAC when performed by trainees.

Characterization of MiFUT11 from Mangifera indica L.: A functional core α1,3-fucosyltransferase potentially involved in the biosynthesis of immunogenic carbohydrates in mango fruit

In higher plants, asparagine-linked oligosaccharides (N-glycans) in glycoproteins carry unique carbohydrate epitopes, namely, a core α1,3-fucose and/or a β1,2-xylose, which are common determinants responsible for the cross-reactivity of plant glycoproteins due to their strong immunogenicity. While these determinants and the relevant genes have been well characterized for herbaceous plants, information concerning whether many food plants cross-react with airborne pollens is not available. In this paper, we report on the characterization of a novel core α1,3-fucosyltransferase gene identified from Mangifera indica L., one of the major plants potentially related to food allergy. Based on sequence information of plant homologues, we amplified a candidate cDNA (MiFUT11) from pericarp tissue. An in vitro assay demonstrated that the recombinant MiFUT11 protein transfers a fucose unit onto both non-fucosylated and core α1,6-fucosylated oligosaccharides. A glycoform analysis using MALDI-TOF mass spectrometry showed that the introduction of the MiFUT11 cDNA increased the production of a core α1,3- and α1,6-fucosylated pauci-mannosidic oligosaccharide in Spodoptera Sf21 cells. Our findings suggest that MiFUT11 is a functional core α1,3-fucosyltransferase gene that is involved in the assembly of cross-reactive N-glycans in mango fruit.

Natural History of Pancreatic Ductal Adenocarcinoma Diagnosed During Observation of Other Organ Cancers

BACKGROUND Pancreatic ductal adenocarcinoma (PDAC) is a rapidly progressive malignancy that exhibits an extremely poor prognosis, with most cases diagnosed at an advanced stage. To date, few reports have explored the natural history of PDAC, and the period leading up to the detection of PDAC as a tumor with contrast-enhanced computed tomography (CECT) remains unclear. Here, we report 3 PDAC cases diagnosed incidentally by repeating imaging examinations during observation of other organ cancers. CASE REPORT Two patients were undergoing postoperative follow-up for colorectal cancer; owing to the elevation of serum CA19-9 or dilatation of the main pancreatic duct, both cases were finally diagnosed with PDAC. Another patient was administered neoadjuvant chemotherapy for a gastrointestinal stromal tumor; the fluorodeoxyglucose uptake in the pancreas with fluorodeoxyglucose positron emission tomography for the treatment assessment led to the diagnosis of PDAC. All patients underwent frequent CECT for assessment of other diseases, and PDAC became visible with CECT within 3-4 months of the appearance of indirect findings of PDAC. CONCLUSIONS The period leading up to the detection of PDAC as a tumor with CECT was approximately 3-4 months. These cases suggest that additional imaging examinations should be performed when the indirect findings of PDAC are noted. This report adds value to the literature by elucidating the natural course of PDAC.

Stratification of Sulfur Species and Microbial Community in Launched Marine Sediment by an Improved Sulfur-Fractionation Method and 16S rRNA Gene Sequencing

With a focus on marine sediment launched by the tsunami accompanying the Great East Japan Earthquake, we examined the vertical (i.e., depths of 0–2, 2–10, and 10–20 mm) profiles of reduced inorganic sulfur species and microbial community using a newly improved sulfur-fractionation method and 16S rRNA gene sequencing. S⁰ accumulated at the largest quantities at a depth of 2–10 mm, while the reduced forms of sulfur, such as iron(II) sulfide and pyrite, were abundant below 2 mm of the sediment. Operational taxonomic units (OTUs) related to chemolithotrophically sulfur-oxidizing Sulfurimonas denitrificans and Sulfurimonas autotrophica were only predominant at 2–10 mm, suggesting the involvement of these OTUs in the oxidation of sulfide to S⁰. In addition, Desulfocapsa sulfexigens, which is capable of chemolithotrophically disproportionating S⁰, prevailed at the same depth, indicating that accumulated S⁰ was converted to sulfate and sulfide. Although no significant differences were observed in sulfate concentrations across the depths examined, specific species of chemoorganotrophic sulfate reducers, i.e., Desulfotignum toluenicum and Desulfosalsimonas propionicica, showed significantly higher abundance at a depth of 2–10 mm than at the other depths examined. Organic matter potentially generated from sulfur oxidation and disproportionation may have served as the carbon source for the growth of these sulfate reducers. The present results demonstrated that sulfur oxidizers, a sulfur disproportionator, and sulfate reducers played vital roles in sulfur cycling with S⁰ as the key inorganic sulfur species in the oxic-anoxic boundary layer of the launched marine sediment.

Prospective, multicenter, observational study of tissue acquisition through EUS-guided fine-needle biopsy using a 25G Franseen needle

Background:

Recently, EUS-guided fine-needle biopsy (EUS-FNB) using a Franseen needle was developed for histological tissue acquisition. However, the yield of a 25G Franseen needle when acquiring histological core tissue has been unclear.

Patients and Methods:

We performed a prospective, multicenter, and observational cohort study that included 100 solid lesions scheduled for EUS-FNB using a 25G Franseen needle at eight centers in Hokkaido, Japan. Only EUS-FNB specimens acquired at the first pass were evaluated without a rapid on-site evaluation. The tissue acquisition rate, acquisition rate of an adequate specimen for histological assessment, the quality of tissue sample, sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), diagnostic accuracy, and adverse events were evaluated.

Results:

We analyzed a total of 100 solid lesions in 100 patients. The patients were 57 males and 43 females with a median age of 70 years. The technical success rate was 100%. The tissue acquisition rate was 95.0%. The acquisition rate of an adequate specimen for histological assessment was 82.0%. The sensitivity, specificity, PPV, NPV, and diagnostic accuracy were 87.0%, 100%, 100%, 40.0%, and 88.0%, respectively. The adverse event rate was 1.0%, and it was reported in only one patient who had a moderate pancreatic fistula.

Conclusions:

EUS-FNB using the 25G Franseen needle was feasible, and adequate histological core tissue samples were acquired with this method.

Endoscopic submucosal dissection for early squamous cell carcinoma in the anal canal and Lugol chromoendoscopy for assessment of the lateral margin

A 66-year-old man underwent follow-up colonoscopy after colon polypectomy. The retroflexed view of the anal canal with white-light imaging revealed a whitish, slightly elevated lesion on the dentate line and an ill-defined flat lesion. A biopsy of the whitish elevation revealed squamous cell carcinoma (SCC), and endoscopic submucosal dissection (ESD) was planned. The lateral margin of the SCC was identified by spraying with Lugol's iodine, and the tumor was resected en bloc with no complications. The pathological findings were SCC in situ with parakeratosis in the whitish elevation and high-grade intraepithelial neoplasia in the ill-defined flat lesion, which exhibited a wide iodine-unstained area by chromoendoscopy. Early SCC in the anal canal is a rare gastrointestinal cancer, and Lugol chromoendoscopy helped visualize the tumor margin for ESD.

Molecular cloning and functional expression of Lewis type α1,3/α1,4-fucosyltransferase cDNAs from Mangifera indica L

In higher plants, complex type N-glycans contain characteristic carbohydrate moieties that are not found in mammals. In particular, the attachment of the Lewis a (Le^a) epitope is currently the only known outer chain elongation that is present in plant N-glycans. Such a modification is of great interest in terms of the biological function of complex type N-glycans in plant species. However, little is known regarding the exact molecular basis underlying their Le^a expression. In the present study, we cloned two novel Lewis type fucosyltransferases (MiFUT13) from mango fruit, Mangifera indica L., heterologously expressed the proteins and structurally and functionally characterized them. Using an HPLC-based assay, we demonstrated that the recombinant MiFUT13 proteins mediate the α1,4-fucosylation of acceptor tetrasaccharides with a strict preference for type I-based structure to type II. The results and other findings suggest that MiFUT13s are involved in the biosynthesis of Le^a containing glycoconjugates in mango fruits.

Short- and long-term outcomes of endoscopic submucosal dissection for early gastric cancer in elderly patients aged 75 years and older

BACKGROUND

Only a few studies have reported long-term outcomes for endoscopic submucosal dissection (ESD) of early gastric cancer (EGC) in elderly patients. The aim of this study was to evaluate the efficacy of ESD for EGC in elderly patients ≥75 years with respect to both short- and long-term outcomes.

METHODS

We reviewed the clinical data of elderly patients ≥75 years who had undergone ESD for EGC at Tonan Hospital from January 2003 to May 2010.

RESULTS

A total of 177 consecutive patients, including 145 with curative resection (CR) and 32 with noncurative resection (non-CR), were examined. Of the 32 patients with non-CR, 15 underwent additional surgery, and lymph node metastases were found in 3 patients. The remaining 17 patients were followed without additional surgery because of advanced age or poor general condition. Procedure-related complications, such as post-ESD bleeding, perforation and pneumonia, were within the acceptable range. The 5-year survival rates of patients with CR, those with additional surgery after non-CR, and those without additional surgery after non-CR were 84.6, 73.3, and 58.8 %, respectively. No deaths were attributable to the original gastric cancer; patients succumbed to other illnesses, including malignancy and respiratory disease.

CONCLUSIONS

In elderly patients, ESD is an acceptable treatment for EGC in terms of both short- and long-term outcomes. Careful clinical assessment of elderly patients is necessary before ESD. After ESD, medical follow-up is important so that other malignancies and diseases that affect the elderly are not overlooked.

Sulfur-Oxidizing Bacteria Mediate Microbial Community Succession and Element Cycling in Launched Marine Sediment

A large amount of marine sediment was launched on land by the Great East Japan earthquake. Here, we employed both on-site and laboratory studies on the launched marine sediment to investigate the succession of microbial communities and its effects on geochemical properties of the sediment. Twenty-two-month on-site survey showed that microbial communities at the uppermost layer (0–2 mm depth) of the sediment changed significantly with time, whereas those at the deeper layer (20–40 mm depth) remained nearly unchanged and kept anaerobic microbial communities. Nine months after the incidence, various sulfur-oxidizing bacteria (SOB) prevailed in the uppermost layer, in which afterwards diverse chemoorganotrophic bacteria predominated. Geochemical analyses indicated that the concentration of metals other than Fe was lower in the uppermost layer than that in the deeper layer. Laboratory study was carried out by incubating the sediment for 57 days, and clearly indicated the dynamic transition of microbial communities in the uppermost layer exposed to atmosphere. SOB affiliated in the class Epsilonproteobacteria rapidly proliferated and dominated at the uppermost layer during the first 3 days, after that Fe(II)-oxidizing bacteria and chemoorganotrophic bacteria were sequentially dominant. Furthermore, the concentration of sulfate ion increased and the pH decreased. Consequently, SOB may have influenced the mobilization of heavy metals in the sediment by metal-bound sulfide oxidation and/or sediment acidification. These results demonstrate that SOB initiated the dynamic shift from the anaerobic to aerobic microbial communities, thereby playing a critical role in element cycling in the marine sediment.

Balloon catheter versus basket catheter for endoscopic bile duct stone extraction: a multicenter randomized trial

BACKGROUND AND STUDY AIMS

Endoscopic bile duct stone (BDS) removal is a well-established treatment; however, the preference for basket or balloon catheters for extraction is operator-dependent. We therefore conducted a multicenter prospective randomized trial to compare catheter performance.

PATIENTS AND METHODS

We enrolled patients with a BDS diameter ≤ 10 mm and common bile duct diameter ≤ 15 mm. Participants were randomly assigned to groups that were treated with basket or balloon catheters between October 2013 and September 2014. The primary endpoint was the rate of complete clearance of the duct; the secondary endpoints were the rate and time to complete clearance in one endoscopic session.

RESULTS

We initially enrolled 172 consecutive patients; 14 were excluded after randomization. The complete clearance rates were 92.3 % (72/78) in the balloon group and 80.0 % (64 /80) in the basket group. The difference in the rates between the two groups was 12.3 percentage points, indicating non-inferiority of the balloon method (non-inferiority limit -10 %; P < 0.001 for non-inferiority). Moreover, the balloon was superior to the basket (P = 0.037). The rate of complete clearance in one endoscopic session was 97.4 % using the balloon and 97.5 % using the basket (P = 1.00). The median times to complete clearance in one endoscopic session were 6.0 minutes (1 - 30) and 7.8 minutes (1 - 37) in the balloon and basket groups, respectively (P = 0.15).

CONCLUSIONS

For extraction of BDSs ≤ 10 mm, complete endoscopic treatment with a single catheter is more likely when choosing a balloon catheter over a basket catheter.University Hospital Medical Information Network Trials Registry: UMIN000011887.

Hybrid mesoporous microspheres from aqueous droplets containing a silica nanoparticle–polymer network in a W/O suspension

Mesoporous hybrid microspheres were fabricated from aqueous droplets of homogeneously distributed silica nanoparticles and reactive polymer in W/O suspension. Further calcination provides mesoporous silica microspheres.

[A Case of Delayed Vascular Injury as a Complication Related to Implanted Central Venous Port Catheter]

A 74-year-old woman with advanced gastric cancer was admitted to our hospital. A central venous (CV) port catheter was implanted into the right subclavian vein for preoperative chemotherapy and parenteral nutritional management. On the 35th day after implantation, she complained of diarrhea, fever and dyspnea. The chest radiograph showed a right-sided massive pleural effusion. As the patient progressively fell into severe respiratory distress, endotracheal intubation was performed for management of respiration by mechanical ventilation. Initially, given the patient's symptoms, she was diagnosed with septic shock. Therefore, after placement of a CV catheter through the right femoral vein, in consideration of the possibility of a port infection, she was treated with thoracentesis and infusion of antibiotics. The patient gradually recovered, and again received parenteral nutrition through the CV port catheter. After the infusion was administered, she complained of dyspnea. A CT scan of the chest revealed a right pleural effusion and displacement of the tip of the CV port catheter out of the wall of the superior vena cava. We diagnosed delayed vascular injury (DVI), and the CV port catheter was removed. She soon recovered with conservative treatment. We speculated that the initial respiratory symptoms such as the pleural effusion were caused by DVI. DVI should therefore be recognized as a complication related to implanted CV port catheters.

1α,25-Dihydroxyvitamin D3 enhances γ-glutamyl transpeptidase activity in LLC-PK1 porcine kidney epithelial cells

Mammalian γ-glutamyl transpeptidase (GGT) is expressed most highly in the kidney and serves to recover the constituent amino acids of glutathione in the proximal tubules. Serum GGT is used as a marker for obstructive jaundice and alcoholic liver disease and it has been reported that urinary GGT is a potential marker for bone resorption. The present study investigated the effect of derivatives of vitamin D3 on GGT activity in LLC-PK1 porcine renal tubular epithelial cells in order to analyze the biochemical basis of bone metabolism-associated alterations in GGT activity in the kidney. In the presence of 1α,25-dihydroxyvitamin D3 [1,25(OH)2VD3], GGT activity was observed to be significantly increased in LLC-PK1 cells, with an increase in GGT activity also found in the cell medium. While the stimulatory effect of 1-OH-VD3 was similar to that of 1,25(OH)2VD3, vitamin D3 and 25-OH-VD3 had no effect on GGT activity. The increased GGT activity caused by 1,25(OH)2VD3 in LLC-PK1 cells was the result of long-term stimulation of the cells, in contrast to the GGT-induced increase in alkaline phosphatase, which is more transient. Polymerase chain reaction analysis revealed that the 1,25(OH)2VD3‑induced increase in GGT activity was due to prolonged GGT turnover, rather than increased GGT expression, as no increase in GGT mRNA expression was observed. Thus, it is likely that the expression of GGT is not entirely constitutive in the kidney, but is altered under certain conditions, including under hormonal regulation.

Early skin toxicity predicts better outcomes, and early tumor shrinkage predicts better response after cetuximab treatment in advanced colorectal cancer

Cetuximab-containing treatments for metastatic colorectal cancer have been shown to have higher overall response rates and longer progression-free and overall survival than other systemic therapies. Cetuximab-related manifestations, including severe skin toxicity and early tumor shrinkage, have been shown to be predictors of response to cetuximab. We hypothesized that early skin toxicity is a predictor of response and better outcomes in patients with advanced colorectal carcinoma. We retrospectively evaluated 62 patients with colorectal adenocarcinoma who had unresectable tumors and were treated with cetuximab in our institution. Skin toxicity grade was evaluated on each treatment day. Tumor size was evaluated using computed tomography prior to treatment and 4-8 weeks after the start of treatment with cetuximab.Patients with early tumor shrinkage after starting treatment with cetuximab had a significantly higher overall response rate (P = 0.0001). Patients with early skin toxicity showed significantly longer overall survival (P = 0.0305), and patients with higher skin toxicity grades had longer progression-free survival (P = 0.0168).We have shown that early tumor shrinkage, early onset of skin toxicity, and high skin toxicity grade are predictors of treatment efficacy and/or outcome in patients with advanced colorectal carcinoma treated with cetuximab.

MD-2-dependent human Toll-like receptor 4 monoclonal antibodies detect extracellular association of Toll-like receptor 4 with extrinsic soluble MD-2 on the cell surface

MD-2 is essential for lipopolysaccharide (LPS) recognition of Toll-like receptor 4 (TLR4) but not for cell surface expression. The TLR4/MD-2 complex is formed intracellularly through co-expression. Extracellular complex formation remains a matter for debate because of the aggregative nature of secreted MD-2 in the absence of TLR4 co-expression. We demonstrated extracellular complex formation using three independent monoclonal antibodies (mAbs), all of which are specific for complexed TLR4 but unreactive with free TLR4 and MD-2. These mAbs bound to TLR4-expressing Ba/F3 cells only when co-cultured with MD-2-secreting Chinese hamster ovary cells or incubated with conditioned medium from these cells. All three mAbs bound the extracellularly formed complex indistinguishably from the intracellularly formed complex in titration studies. In addition, we demonstrated that two mAbs lost their affinity for TLR4/MD-2 on LPS stimulation, suggesting that these mAbs bound to conformation-sensitive epitopes. This was also found when the extracellularly formed complex was stimulated with LPS. Additionally, we showed that cell surface TLR4 and extrinsically secreted MD-2 are capable of forming the functional complex extracellularly, indicating an additional or alternative pathway for the complex formation.

Difucosylation of chitooligosaccharides by eukaryote and prokaryote α1,6-fucosyltransferases

BACKGROUND

The synthesis of eukaryotic N-glycans and the rhizobia Nod factor both involve α1,6-fucosylation. These fucosylations are catalyzed by eukaryotic α1,6-fucosyltransferase, FUT8, and rhizobial enzyme, NodZ. The two enzymes have similar enzymatic properties and structures but display different acceptor specificities: FUT8 and NodZ prefer N-glycan and chitooligosaccharide, respectively. This study was conducted to examine the fucosylation of chitooligosaccharides by FUT8 and NodZ and to characterize the resulting difucosylated chitooligosaccharides in terms of their resistance to hydrolysis by glycosidases.

METHODS

The issue of whether FUT8 or NodZ catalyzes the further fucosylation of chitooligosaccharides that had first been monofucosylated by the other. The oligosaccharide products from the successive reactions were analyzed by normal-phase high performance liquid chromatography, mass spectrometry and nuclear magnetic resonance. The effect of difucosylation on sensitivity to glycosidase digestion was also investigated.

RESULTS

Both FUT8 and NodZ are able to further fucosylate the monofucosylated chitooligosaccharides. Structural analyses of the resulting oligosaccharides showed that the reducing terminal GlcNAc residue and the third GlcNAc residue from the non-reducing end are fucosylated via α1,6-linkages. The difucosylation protected the oligosaccharides from extensive degradation to GlcNAc by hexosamidase and lysozyme, and also even from defucosylation by fucosidase.

CONCLUSIONS

The sequential actions of FUT8 and NodZ on common substrates effectively produce site-specific-difucosylated chitooligosaccharides. This modification confers protection to the oligosaccharides against various glycosidases.

GENERAL SIGNIFICANCE

The action of a combination of eukaryotic and bacterial α1,6-fucosyltransferases on chitooligosaccharides results in the formation of difucosylated products, which serves to stabilize chitooligosaccharides against the action of glycosidases.

[A case of intragastric wall abscess formation during bevacizumab combined chemotherapy]

A 38-year-old man was given a diagnosis of as sigmoid colon cancer and underwent sigmoid colectomy. Post-operative pathological staging was stage IIIb. He then underwent adjuvant chemotherapy. One year and 4 months after the surgery, CT scans revealed multiple liver and lung metastases. He was given mFOLFOX6+bevacizumab, which was changed later to FOLFIRI+bevacizumab. After these chemotherapies, he was admitted to the hospital due to sudden abdominal pain and high grade fever. Obstructive jaundice was initially diagnosed, but detailed study of initial CT revealed intragastric wall abscess. After the drainage of the abscess, his conditions improved. We speculated that the abscess formation was caused by mucosal damage due to bevacizumab.