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Biology subjects

Han, Y.-S.

Publications and source records attributed to Han, Y.-S..

3 recordsLinked to original sources

A decade after being listed as Endangered: Japanese eel stock inferred from fishery-dependent and independent monitoring records (Preprint)

This study assesses recent trends in the abundance of Japanese eels (Anguilla japonica), which have been listed as Endangered on the IUCN Red List of Threatened Species since 2014, by updating previously reported coastal fisheries datasets and incorporating new freshwater data and scientific monitoring records for glass eels in Japan and Taiwan. Catch-per-unit-effort (CPUE) data for yellow and silver eels revealed statistically significant declines in seven of eight datasets, with projected reductions over three generations (24 years) ranging from 79.2% to 99.9%. In contrast, no significant temporal trends were detected in the CPUE of glass eels, likely due to high interannual variability driven by oceanic conditions. The integration of freshwater and coastal data, along with fishery-independent monitoring, enhances the reliability of these indicators. The results provided in this study represent the best currently available indicators of Japanese eel population dynamics.

ecology↗

Stable species boundaries despite ten million years of hybridization in tropical eels

Genomic evidence is increasingly underpinning that hybridization between taxa is commonplace, challenging our views on the mechanisms that maintain their boundaries. Here, we focus on seven catadromous eel species (genus Anguilla), and use genome-wide sequence data from more than 450 individuals sampled across the tropical Indo-Pacific, morphological information, and three newly assembled draft genomes to compare contemporary patterns of hybridization with signatures of past gene flow across a time-calibrated phylogeny. We show that the seven species have remained distinct entities for up to 10 million years, despite a dynamic scenario of incomplete isolation whereby the current frequencies of hybridization across species pairs (over 5% of all individuals were either F1 hybrids or backcrosses) contrast remarkably with patterns of past introgression. Based on near-complete asymmetry in the directionality of hybridization and decreasing frequencies of later-generation hybrids, we identify cytonuclear incompatibilities and hybrid breakdown as two powerful mechanisms that can support species cohesion even when hybridization has been pervasive throughout the evolutionary history of entire clades.

evolutionary biology↗

Protect TUDCA stimulated CKD-derived hMSCs against the CKD-Ischemic disease via upregulation of PrPC

Although autologous human mesenchymal stem cells (hMSCs) are a promising source for regenerative stem cell therapy, the barriers associated with pathophysiological conditions in this disease limit therapeutic applicability to patients. We proved treatment of CKD-hMSCs with TUDCA enhanced the mitochondrial function of these cells and increased complex I & IV enzymatic activity, increasing PINK1 expression and decreasing mitochondrial O2*- and mitochondrial fusion in a PrPC-dependent pathway. Moreover, TH-1 cells enhanced viability when co-cultured in vitro with TUDCA-treated CKD-hMSC. In vivo, tail vein injection of TUDCA-treated CKD-hMSCs into the mouse model of CKD associated with hindlimb ischemia enhanced kidney recovery, the blood perfusion ratio, vessel formation, and prevented limb loss, and foot necrosis along with restored expression of PrPC in the blood serum of the mice. These data suggest that TUDCA-treated CKD-hMSCs are a promising new autologous stem cell therapeutic intervention that dually treats cardiovascular problems and CKD in patients.

cell biology↗