Yuya Sugiyama

Hosei University

Background and study aims Gastric adenocarcinoma of the fundic gland type (GA-FG) is characterized by an elevated lesion with vessel dilation exhibiting branching architecture (DVBA). However, this feature is also found in fundic gland polyps (FGPs), posing a challenge in their differentiation. In this study, we aimed to investigate the clinicopath...

Background and Aim Image enhancement endoscopy techniques, such as linked color imaging (LCI) and autofluorescence imaging (AFI), have shown promise in diagnosing mucosal inflammation in ulcerative colitis (UC). However, no studies have directly compared the diagnostic efficacy of LCI and AFI. This prospective observational study aimed to compare t...

Rationale Both ulcerative colitis (UC) and sarcoidosis are chronic inflammatory diseases with unknown etiologies and are rare. However, the odds ratio in UC patients has been reported to range from 1.7 to 2.1, suggesting a potential etiology between sarcoidosis and UC. Furthermore, the underlying etiologies of UC and sarcoidosis remain unidentified...

Introduction A remission induction therapy of granulocyte and monocyte adsorptive apheresis (GMA) was given to patients with Crohn's disease (CD). However, establishing an appropriate treatment strategy for GMA in patients with CD remains unclear. Methods This study evaluated the clinical efficacy and subsequent clinical progression after GMA in p...

Rationale: Latent tuberculosis (TB) infection screening before inducing anti-tumor necrosis factor (anti-TNF) alpha agents is important to prevent TB reactivation. However, latent TB infection reactivation may still occur, and the ideal therapeutic strategy for patients with inflammatory bowel disease (IBD) who develop active TB infection has not...

Background: A remission induction therapy of granulocyte and monocyte adsorptive apheresis (GMA) with Adacolumn was given to patients with active Crohn’s disease (CD). However, establishing an appropriate treatment strategy for GMA in patients with active CD remains unclear. Methods: This multicenter retrospective cohort study encompassed patients...

Background: Granulocyte and monocyte adsorptive apheresis (GMA) with Adacolumn has been used as a remission induction therapy for patients with active ulcerative colitis (UC). Herein, we investigated the influence of concomitant medications in the remission induction of GMA in patients with active UC. Methods: This multicenter retrospective coho...

Background and study aims Recent advances in cancer treatment have involved the clinical application of immune checkpoint inhibitors (ICIs) for various type of cancers. The adverse events associated with ICIs are generally referred to as immune-related adverse events (irAEs). Gastrointestinal irAEs are a major disorder, but gastritis is not frequen...

A 24-year-old woman was admitted to our hospital due to abdominal pain and a high fever. She was diagnosed with ileocolonic Crohn's disease (CD), complicated with a gastro-colic fistula and splenomegaly. After initial treatment with an infliximab-biosimilar, all blood cell line counts markedly decreased. Three-dimensional reconstructed computed tom...

Background: Granulocyte and monocyte adsorptive apheresis (GMA) with Adacolumn has been widely used as a remission induction therapy for patients with active ulcerative colitis (UC). However, an appropriate GMA treatment strategy related to concomitant medication in patients with active UC has not been established. Herein, we investigated the influ...

Background The impact of the body composition on the pathophysiology and clinical course of Crohn's disease (CD) has not been fully elucidated. Aims To reveal the correlations among body composition and long-term outcomes in CD after anti-TNF therapy. Methods Ninety-one patients who received anti-TNF therapy as their first biologic treatment were...

Background Reconstruction surgery-associated stricture frequently occurs in patients with long-gap esophageal atresia (LGEA). While several endoscopic dilatation methods have been applied and would be desirable, endoscopic recanalization is very difficult in cases with complete esophageal closure. Surgical treatment has been performed for a severe...

Background Carbazochrome sodium sulfonate (CSS) is conventionally administered to prevent post-endoscopic submucosal dissection (ESD) bleeding in many institutions, but research on its preventive efficacy is lacking. Therefore, we investigated the risk of post-ESD bleeding and the preventive efficacy of CSS administration. Methods We retrospective...

Background Chemotherapy for advanced gastric cancer is recommended in the guidelines; however, later-line treatment remains controversial. Since immune checkpoint inhibitors have been used for the treatment of various malignancies, trials have been performed for gastric cancer. A phase 3 trial indicated the survival benefit of nivolumab monotherapy...

Endoscopic finding of immune checkpoint inhibitor‐related gastritis is characterized as shallow network‐like erosion, which is termed spiderwebs‐like appearance.

Background Granulocyte and monocyte adsorptive apheresis (GMA) is widely used as a remission induction therapy for active ulcerative colitis (UC) patients. However, there are no available biomarkers for predicting the clinical outcome of GMA. We investigated the utility of Fecal calprotectin (FC) as a biomarker for predicting the clinical outcome d...

Background: Screening of latent tuberculosis (TB) before the induction of anti-tumor necrosis factor (anti-TNF) agents is very important to prevent the reactivation of TB. However, active TB can still occur, and the ideal therapeutic strategy for IBD patients who develop active TB has not been established. Case presentation: A 21-year-old Vietnames...

An attempt to use combination therapy with anti-tumor necrosis factor α (TNFα) antibodies and tacrolimus (TAC) has been tried to induce remission in ulcerative colitis (UC). However, the optimal dose of TAC in combination therapy with anti-TNFα antibodies (TAC + anti-TNFα therapy) remains unclear. We examined the efficacy of various doses of TAC +...

Gastric adenocarcinoma of the fundic gland mucosa type (GA-FGM) was proposed as a new variant of gastric adenocarcinoma of the fundic gland type (GA-FG). However, at present, the influence of Helicobacter pylori and the speed of progression and degree of malignancy in GA-FGM remain unclear. Herein, we report the first case of intramucosal GA-FGM th...

A 60-year-old man had received octreotide for a metastatic neuroendocrine tumor (NET) in the rectum. Computed tomography and ultrasonography revealed a cardiac tumor, diffuse thickness of the ventricular wall and pericardial effusion, which was diagnosed as cardiac metastasis. The metastatic lesions continued to grow despite the alteration of chemo...

Background: Granulocyte and monocyte adsorptive apheresis (GMA) is widely used as a remission induction therapy for active ulcerative colitis (UC) patients. However, there are no available biomarkers for predicting the clinical outcome of GMA. We investigated the utility of Fecal calprotectin (FC) as a biomarker for predicting the clinical outcome...

Rationale: Gastric mixed adenoneuroendocrine carcinoma (gMANEC) is a rare malignant tumor. Most gMANECs are diagnosed at an advanced stage and have a worse prognosis than gastric adenocarcinoma. In order to improve the prognosis, it is necessary to diagnose gMANEC at an early stage. However, the endoscopic features of early gMANECs are unclear. We...

Background IBD are chronic immune disorders of unclear etiology. TNF inhibitors are effective for IBD treatment but are much more expensive than traditional treatments. A large number of clinical trials of infliximab biosimilar (CT-P13) have suggested that the administration of biosimilars provides high efficacy and safety similar to that of the or...

Pancreatobiliary tumors frequently contain multiple malignant and precancerous lesions; however, the origin of the driver mutations and the mechanisms that underlie the generation of distinct clones within an organ field remain unclear. Herein, we describe a 76-year-old male suffering from moderately differentiated adenocarcinomas of the pancreas t...

Background Steroid therapy is primarily used to prevent esophageal stricture after endoscopic submucosal dissection (ESD). However, esophageal stricture can still occur after preventive therapy, and the effect of preventive steroid therapy cannot be predicted before stricture formation. This study aimed to clarify the risk factors for esophageal st...

Background: Venous thromboembolism (VTE) has been shown to be more frequent in inflammatory bowel disease (IBD) than in the general population in Western studies. However, the actual state of VTE in Asian IBD remains poorly understood. Aims: To reveal the incidence of VTE in IBD patients in Japan. Methods: Eighty-five patients admitted to 3 ga...

Background: Takayasu's arteritis (TA) is a large-vessel vasculitis pathologically characterized by granulomatous necrotizing vasculitis with giant cells. Although the cause of TA is still unclear, genetic factors as well as immunological abnormalities, particularly the overactivation of Th1 and Th-17, are considered to play important roles in the...

In this study, an activation strategy for Grubbs-Hoveyda second-generation-type catalysts by utilizing the intramolecular steric strain on the ligands is described. The variant, which is expected to exhibit intramolecular steric strain, containing extensively spread aromatic and alkoxy groups in the ligand structure was prepared and examined. The c...

A liquid-phase split-type synthesis of various tripeptides and pentapeptides was conducted using a fluorous-Fmoc protection strategy. Fluorous-Fmoc reagents were effectively used as both the protecting group for the amino function and the encoding tag for the amino acid structure. Several of the synthetic peptides prepared showed high activities in...

Various novel Grubbs-Hoveyda second-generation catalysts activated by a fluorous tag on the ligands were prepared. The catalyst bearing the 1-naphthyl group on the bidentate ligand exhibited the highest catalytic activity among the studied catalysts for the ring-closing-metathesis reaction of diethyl 2-allyl-2-(2-methylallyl)malonate.

Various Grubbs–Hoveyda second-generation catalysts activated by intramolecular steric strain were prepared. The variant bearing a 9-anthracenyl group in the ligand moiety exhibited the highest catalytic activity. The new anthracenyl-type-activated catalyst was used in a ring-closing metathesis reaction to effectively provide a 4-substituted product...

An optimized, multi-gram scale synthesis of fluorous-Fmoc reagents is described. Fmoc reagents bearing C3F7, C4F9, and C6F13 chains were prepared on multi-gram scale (ca. 1.0–7.0 g) in eight steps with overall yields of 73%, 60%, and 90%, respectively. The order of addition of the fluorous alkenes in a one-pot double tagging Heck reaction was also...

A liquid-phase split-type synthesis of all the stereoisomers of dendroamide A, which exhibits multidrug-resistance reversing activity, has been carried out. The key to the concise synthesis was the fluorous-Fmoc protection strategy of each of the starting materials (D- and L-alanine and D- and L-valine). By using the fluorous-Fmoc encoding method,...

A fluorous Grubbs–Hoveyda metathesis catalyst supported on Teflon® powder, that readily moves between the solid phase (Teflon®) and the liquid phase (DMF) was prepared. By modulating the hydrophobicity of the reaction medium at the end of the reaction, the supported catalyst could be recovered by simple filtration even though the catalyst existed i...

The asymmetric epoxidation of aromatic olefins using optically active first generation manganese salen catalysts and light fluorous variants was examined. Although a slight decrease in the enantioselectivity of the product was observed when light fluorous catalysts were employed, the activities of these catalysts were higher than those of the non-f...

A liquid-phase mixture synthesis of 18 tripeptides, some of which are analogues of ACE inhibitors, was effectively conducted by using fluorous Fmoc reagents as encoding tags.

A concise liquid-phase combinatorial synthesis of all stereoisomers of Tenuecyclamide A was achieved using a mixture of D/L-alanine with each stereoisomer encoded by a different f-Fmoc tag (shown by the clip in above figure). The synthetic strategy using f-Fmoc reagents as the protecting group for amino acids has been demonstrated to be a useful me...

The concise synthesis of fluorous Fmoc (f-Fmoc) reagents bearing C3F7 or C4F9 or C6F13 chains were achieved by fluorous mixture synthesis. The fluorous tagging process was effectively conducted using Heck type reaction of the bis-diazonium salt and the corresponding fluorous olefine, each bearing a different fluorous tag, by a one-pot double taggin...

The entire study of condensation reactions using various fluorous Mukaiyama reagents, including a novel medium-fluorous strategy, is described. A Mukaiyama reagent bearing a medium-fluorous content tag, between 40 and 60% fluorine by weight, was prepared and examined in ester and amide-forming condensation reactions. At the end of the reactions, th...

The observed rate enhancement for the condensation reaction between 2-phenyl benzoic acid and isopropanol mediated by fluorous Mukaiyama reagents is described. It is shown that Mukaiyama reagents bearing a fluorous tag increase the reaction rate considerably when compared to their non-fluorous tagged counterpart. Furthermore, it is observed that th...