Biology subjects

Kawamoto, T.

Publications and source records attributed to Kawamoto, T..

5 recordsLinked to original sources

bioRxiv2026

From introduction to eradication: reconstructing population size and removal history of an invasive species

O_LIUnderstanding the processes underlying successful eradication of invasive species is essential for achieving global island conservation goals. Despite the widespread availability of capture records from eradication programs, modeling frameworks that utilize these datasets to elucidate spatio-temporal population dynamics remain underdeveloped. C_LIO_LIIn this study, we reconstructed the spatio-temporal population dynamics of the small Indian mongoose on Amami-Oshima Island (712 km{superscript 2}), Japan, where the species was introduced in 1979 and officially declared eradicated in 2024 after more than 30 years of systematic removal. We integrated introduction records, capture data, and monitoring data using a hierarchical harvest-based model (HBM). To evaluate the models capacity to support management decisions and assess eradication success, we conducted retrospective analyses and compared estimated eradication probabilities with those obtained from a rapid eradication assessment (REA; Samaniego-Herrera et al., 2013). C_LIO_LIThe estimated population size (before reproduction) peaked at 5,449 individuals (95% CI: 4,703, 6,175) in 2000 and subsequently declined almost monotonically. The maximum invaded area was 547.78 km{superscript 2} (posterior median, 95% CI: 496.47, 566.04) in 2009, indicating that the removal program successfully prevented island-wide expansion. Retrospective analyses showed that population estimates remained within the 95% credible intervals of the full dataset estimates, demonstrating temporal consistency. Eradication probabilities estimated by the HBM were substantially higher than those from the REA, highlighting the sensitivity of estimates to fine-scale heterogeneity in detection processes. C_LIO_LISynthesis and applications: Hierarchical HBMs provide a powerful framework for reconstructing, predicting, and evaluating invasive species eradication dynamics. Being aware of the limitations for application to eradication evaluations, HBMs can support adaptive management in long-term eradication programs and improve our understanding of the mechanisms underlying successful eradication. C_LI

ecology↗

bioRxiv2026

Regional Differences in Dorsal Skin Determine the Rate of Adhesive Material-Induced Hair Regeneration

Dorsal skin is widely used in mouse wound-healing, dermatitis, and hair-cycle models, but is often treated as a uniform site. We investigated whether adhesive material (cyanoacrylate)-induced hair regeneration, a model we previously reported, differs by position within the dorsal skin. Adhesive material was applied to four regions along the cranial-to-caudal axis of the mouse dorsal skin. Hair regrowth appeared earlier at the cranial sites than at the caudal sites, and this difference persisted through late anagen and the anagen-to-catagen transition. In contrast, hair regrowth after full-thickness skin excision was slower, smaller in area, and less reproducible than that after adhesive material application. Expression of Hox genes, including Hoxa9, Hoxb9, Hoxc9, Hoxa10, and Hoxc10, was higher at the caudal sites than at the cranial sites but did not correlate with the timing of hair regrowth. RNA sequencing of intact skin from the cranial and caudal sites revealed distinct baseline profiles, including differences in the Wnt inhibitor Sfrp4 and the adipogenic genes Ppar{gamma} and Fabp4. Early after adhesive material application, histological changes and the expression of inflammation- and tissue-repair-related genes also differed between the cranial and caudal skin. These findings indicate that mouse dorsal skin is not a uniform experimental field and that cranial-to-caudal position should be considered when designing and interpreting hair-regeneration and wound-healing experiments in mice.

developmental biology↗

bioRxiv2024

Large ungulates will be present in most of Japan by 2050 owing to natural expansion and human population shrinkage

The aims of this study were to elucidate factors contributing to the expansion of the distributions of sika deer and wild boar in Japan and to predict the expansion of their distributions by 2025, 2050, and 2100. A site occupancy model was constructed using information on species distribution collected by the Ministry of the Environment in 1978, 2003, 2014, and 2018, days of snow cover, forested and road areas, elevation, human population, and distance from occupied grid cells as covariates to calculate the probability of distribution change. Factors contributing to distribution expansion were elucidated and distribution expansion was predicted. Distance from occupied grid cells had the strongest influence on distribution expansion, followed by the inherent ability of each species to expand its distribution. For sika deer, human population had a strong negative effect and elevation and number of days of snow cover were important. For wild boar, forest area and elevation had high importance. Predictions of future distribution showed that both species will be distributed over 90% of Japan by 2050 and over 100% by 2100.

ecology↗

bioRxiv2022

ALDH2 DEFICIENCY INCREASES SUSCEPTIBILITY TO BINGE ALCOHOL-INDUCED GUT LEAKINESS, ENDOTOXEMIA, AND ACUTE LIVER INJURY IN MICE THROUGH THE GUT-LIVER AXIS

Mitochondrial aldehyde dehydrogenase 2 (ALDH2) is the major enzyme responsible for metabolizing toxic acetaldehyde to acetate and acts as a protective or defensive protein against various disease states associated with alcohol used disorder (AUD), including alcoholic liver disease (ALD), and elevated oxidative stress. We hypothesized that Aldh2-knockout (KO) mice are susceptible to binge alcohol-mediated liver injury than wild-type (WT) mice through increased gut leakiness and endotoxemia. Therefore, this study aimed to investigate the protective role of ALDH2 in binge alcohol-induced gut permeability, endotoxemia, and acute inflammatory liver injury by exposing Aldh2-KO or WT mice to a single oral dose of binge alcohol 3.5, 4.0, or 5.0 g/kg. Our findings showed for the first time that ALDH2 deficiency in Aldh2-KO mice increases their sensitivity to alcohol-induced oxidative and nitrative stress, enterocyte apoptosis, and nitration of gut tight junction (TJ) and adherent junction (AJ) proteins, leading to their degradation. These resulted in gut leakiness and endotoxemia in Aldh2-KO mice after exposure to a single dose of ethanol even at 3.5 g/kg, while no changes were observed in the corresponding WT mice. The elevated serum endotoxin (lipopolysaccharide, LPS) and/or bacterial translocation contributed to systemic inflammation, hepatocyte apoptosis, and subsequently acute liver injury, indicating the disruption in the gut-liver axis. Furthermore, treatment with Daidzin, an ALDH2 inhibitor, exacerbated ethanol-induced cell permeability and reduced TJ/AJ proteins in T84 human colonic cells. These changes were reversed by Alda-1, an ALDH2 activator, indicating a crucial role of ALDH2 in protecting against alcohol-induced epithelial barrier dysfunction. All these findings suggest that ALDH2 deficiency or gene mutation in humans is a risk factor to alcohol-mediated gut and liver injury, and ALDH2 could be an important therapeutic target against alcohol-associated tissue/organ damage. HighlightsO_LIBinge alcohol increases oxidative and nitrative stress in the intestine and liver. C_LIO_LIBinge alcohol causes gut leakiness, endotoxemia, and acute liver injury. C_LIO_LILeaky gut is caused by elevated degradation of nitrated intestinal TJ/AJ proteins. C_LIO_LIAldh2-KO mice are susceptible to binge-alcohol-induced leaky gut and liver injury. C_LIO_LIALDH2 inhibition increases alcohol-induced T84 colonic epithelial cell permeability. C_LI

pharmacology and toxicology↗

bioRxiv2019

Comparison of long-term outcomes between enteral nutrition via gastrostomy and total parenteral nutrition in the elderly with dysphagia: A propensity-matched cohort study

BackgroundThe long-term outcomes of artificial nutrition and hydration (ANH) in the elderly with dysphagia remain uncertain. Enteral nutrition via percutaneous endoscopic gastrostomy (PEG) and total parenteral nutrition (TPN) are major methods of ANH. Although both can be a life-prolonging treatments, Japan has recently come to view PEG as representative of unnecessary life-prolonging treatment. Consequently, TPN is often chosen for ANH instead. This study aimed to compare the long-term outcomes between PEG and TPN in the elderly.\n\nMethodsThis single-center retrospective cohort study identified 253 elderly patients with dysphagia who received enteral nutrition via PEG (n=180) or TPN (n=73) between January 2014 and January 2017. The primary outcome was survival time. Secondary outcomes were oral intake recovery, discharge to home, and the incidence of severe pneumonia and sepsis. We performed one-to-one propensity score matching using a 0.05 caliper. The Kaplan-Meier method, log-rank test, and Cox proportional hazards model were used to analyze the survival time between groups.\n\nResultsOlder patients with lower nutritional states, and severe dementia were more likely to receive TPN. Propensity score matching created 55 pairs. Survival time was significantly longer in the PEG group (median, 317 vs 195 days; P=0.017). The hazard ratio for PEG relative to TPN was 0.60 (95% confidence interval: 0.39-0.92; P=0.019). There were no significant differences between the groups in oral intake recovery and discharge to home. The incidence of severe pneumonia was significantly higher in the PEG group (50.9% vs 25.5%, P=0.010), whereas sepsis was significantly higher in the TPN group (10.9% vs 30.9%, P=0.018).\n\nConclusionsPEG was associated with a significantly longer survival time, a higher incidence of severe pneumonia, and a lower incidence of sepsis compared with TPN. These results can be used in the decision-making process before initiating ANH.

scientific communication and education↗