Yoshiki Hirooka

Background and Aims: Crohn’s disease (CD) is a chronic inflammatory bowel disease characterized by gastrointestinal inflammation, with gut microbiota dysbiosis playing a key role in its onset and progression. This study aimed to evaluate whether 1-kestose supplementation modulates gut microbiota composition and mucin degradation–related biomarkers in patients with clinically inactive to mild CD, and to explore plausible ecological mechanisms in vitro. Study Design: Single-arm pilot intervention study with exploratory laboratory experiments. Place and Duration of Study: Samples were collected at Tokai University Hospital (Japan), and microbiome/qPCR analyses and in vitro assays were performed at Fujita Health University (Japan). The supplementation period was four months. Methodology: Nineteen patients with clinically inactive to mild CD (CDAI ≤ 220) received 1-kestose (3 g) twice daily for 4 months. Fecal microbiota composition was assessed by 16S rRNA gene sequencing, and qPCR quantified nanA homologs (nan levels) as a functional marker related to mucin-degrading potential. Clinical biomarkers (CDAI, fecal calprotectin, CRP, albumin) were monitored. To investigate potential mechanisms, in vitro cultures of Ruminococcus gnavus and Bifidobacterium longum were performed under sugar-supplemented conditions, including 1-kestose, and growth responses were evaluated; short-chain fatty acids (SCFAs) were descriptively assessed in pooled culture supernatants. Results: Clinical biomarkers remained stable throughout supplementation. 1-kestose intake was associated with an increased relative abundance of Bifidobacterium and a decreased abundance of Blautia, along with reduced fecal nan levels. In vitro, B. longum showed enhanced early growth with 1-kestose compared with other sugars, whereas R. gnavus exhibited impaired growth under acidic conditions. Exploratory SCFA measurements suggested higher acetate in sugar-supplemented B. longum cultures. Conclusion: In this single-arm pilot cohort of patients with clinically inactive to mild CD, 1-kestose supplementation was associated with shifts toward potentially beneficial taxa and a reduction in nan levels, a functional marker linked to mucin-degrading potential. These findings, supported by exploratory in vitro observations, suggest that 1-kestose may modulate gut ecological conditions; however, clinical efficacy and causality require confirmation in randomized, placebo-controlled trials with detailed dietary and medication monitoring.

BACKGROUND/AIM: Atezolizumab plus bevacizumab (Ate+Bev) is widely used as first-line therapy for unresectable hepatocellular carcinoma (HCC). However, a subset of patients experience early disease progression, often detected at the first radiologic assessment around 6 weeks. Evidence guiding second-line therapy in this subgroup is limited, and the clinical value of lenvatinib after early progressive disease (PD) remains unclear. PATIENTS AND METHODS: We retrospectively analyzed 36 patients with unresectable HCC who received lenvatinib after failure of first-line Ate+Bev. Patients were stratified by early PD, defined as radiologic progression at the scheduled 6-week assessment after starting Ate+Bev. Outcomes included antitumor response, progression-free survival (PFS), and overall survival (OS). RESULTS: Objective response rate (ORR) and disease control rate (DCR) assessed by RECIST 1.1 were comparable between patients with and without early PD (ORR: 28.6% vs. 13.8%; DCR: 85.7% vs. 86.2%; p=0.342). Median PFS was also similar between groups [5.2 months (95% confidence interval=1.9-NA) vs. 6.1 months (3.7-7.5); p=0.307]. In multivariate analyses adjusting for Child-Pugh class, Barcelona Clinic Liver Cancer (BCLC) stage, and reduced starting dose, early PD was not significantly associated with either PFS or OS, whereas Child-Pugh class A was independently associated with improved OS. Correlation between first- and second-line PFS was weak and non-significant (r=0.077, p=0.682). CONCLUSION: Lenvatinib demonstrated comparable antitumor activity and survival outcomes even in patients with early PD on first-line Ate+Bev, indicating that early radiologic progression does not necessarily signify refractoriness to subsequent systemic therapy. These findings support lenvatinib as a viable second-line option regardless of early Ate+Bev response, particularly in patients with preserved liver function. Larger prospective studies are needed to confirm these observations.

Aims: To characterize fecal gut microbiota features associated with a history of aggression in dogs and to explore whether supplementation with the prebiotic fructooligosaccharide 1-kestose is associated with alterations in gut microbiota composition and owner-reported aggression-related behaviors. Study Design: An exploratory, non-randomized field study comparing aggressive and non-aggressive client-owned dogs, followed by a single-arm pre–post supplementation study in aggressive dogs with owner-reported behavioral outcomes. Place and Duration of Study: The study was conducted in Japan between 2021 and 2023, with a 60-day 1-kestose supplementation period for the intervention group. Methodology: Fecal samples from aggressive toy poodles (Agg; n = 10) and non-aggressive controls (N-Agg; n = 6) were analyzed using 16S rRNA gene sequencing. Dogs in the Agg group received 1-kestose (400 mg/day) for 60 days. Behavioral outcomes were assessed before and after supplementation using the shortened, owner-reported Canine Behavioral Assessment and Research Questionnaire (C-BARQ). Genome analysis of Blautia caecimuris was conducted to identify glycoside hydrolase family 32 (GH32) enzymes, and a recombinant GH32 enzyme was functionally characterized for fructooligosaccharide hydrolysis. Results: At baseline, Agg dogs differed in gut microbial β-diversity from N-Agg dogs and showed higher relative abundances of Mediterraneibacter gnavus, the Segatella copri group, and the Phocaeicola vulgatus group. Following 1-kestose supplementation, M. gnavus was lower, the B. caecimuris group was higher, and the β-diversity difference between groups diminished. In parallel, owner-reported aggression-related C-BARQ items—particularly responses to unfamiliar dogs and strangers near the home—were lower after supplementation. The characterized GH32 enzyme from B. caecimuris hydrolyzed 1-kestose and nystose. Conclusion: These findings indicate that 1-kestose supplementation is associated with concurrent alterations in the canine gut microbiota and owner-reported aggression-related behavioral scores. While causality cannot be established, the results support further investigation of microbiota–behavior associations using larger, well-controlled study designs incorporating objective physiological and microbial measurements.