48 research outputs found

    Phylogeography of the endangered orchids Cypripedium japonicum and Cypripedium formosanum in East Asia: Deep divergence at infra- and interspecific levels

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    To date, little is known about the past evolutionary trajectories of rare and endangered orchids native to mainland China, Japan, and Korea (the CJK region). In this study, we focus on two endangered orchids, Cypripedium japonicum (present in the three countries) and C. formosanum (endemic to Taiwan), to understand the divergence/speciation models that would have been operating in this group, including genetic diversity, geographic structure, and colonization pathways across the region. Using a combination of five cpDNA regions, we reconstructed phylogenetic trees and investigated the genetic diversity/structure of 20 populations. Ecological niche modeling was used to gain insight into the paleodistribution and dispersal corridors at the Last Glacial Maximum and to survey climatic niche differences. Populations from mainland China + Korea, Japan, and Taiwan formed three distinct monophyletic lineages and were placed into separate genetic clusters, agreeing with geographic barriers and species boundaries. Populations of C. japonicum in mainland China harbored the highest diversity, suggesting the presence of multiple glacial refugia. The Korean populations would have originated from either western/central or eastern China, probably using a dispersal corridor across the East China Sea shelf. The divergence of C. formosanum is proposed under an allopatric speciation model, also highly influenced by a climate niche shift. In the context of previous studies, a deep divergence in cpDNA sequences between Chinese + Korean and Japanese populations of C. japonicum may be taken as an example of the speciation events of the CJK flora since the late Neogene that have led to its current species richness.This study was supported by the Biodiversity Survey, Observation and Assessment Program of the Ministry of Ecology and Environment of China to HZT and by Basic Science Program through the National Research Foundation of Korea (NRF-2017R1A2B4012215) to MGC, and funded by the Ministry of Science and ICT of the Republic of Korea (NRF-2020R1I1A3074635) to MYC.INTRODUCTION MATERIALS AND METHODS Study species Population sampling DNA extraction cpDNA-PCR optimum primer selection cpDNA sequence alignment and assembly Haplotype distribution, phylogenetic analyses, and genetic diversity Genetic differentiation and structure Mismatch distribution analysis, neutrality detection, and demographic history ENM and population connectivity Niche comparisons in E-space RESULTS Haplotype distribution and phylogeny Genetic diversity Genetic differentiation and structure Mismatch distribution analysis, neutrality detection, and demographic history ENM and population connectivity Niche comparisons in E-space DISCUSSION Deep genetic and climatic divergence of Cypripedium sect. Flabellinervia in the CJK region: taxonomic considerations Haplotype and nucleotide diversity in Cypripedium sect. Flabellinervia: inference of glacial refugia and demographic history Origin of Korean populations of Cypripedium japonicum Origin of Cypripedium formosanum CONCLUSIONS AUTHOR CONTRIBUTIONS ACKNOWLEDGEMENTS Appendix 1: The cpDNA sequence information of Cypripedium sect. Flabellinervia deposited in the GenBank databas

    Cryptosporidium Infection in Juvenile Pet Rabbits

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    Development of Droplet-PIXE system for Environmental Monitoring Samples

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    Behaviour of radionuclides in the environment and organisms has been investigated to evaluate the radiation effect on human using stable isotopes using PIXE analysis at the PASTA facilities in the NIRS. Since some of the environmental monitoring samples are in the liquid state, pre-treatment of the samples such as filtration, drying and solidification are necessary prior to the PIXE analysis. During sample preparation process, there may be loss of element due to sublimation or evaporation that must be taken care for quantitative analysis. To avoid such problems, we have developed a suitable dropletPIXE system. It is based on the following points,(i) development of equipment with a good stability to supply a droplet of good reproducibility, (ii) optimisation of all equipments that includes a stable beam line (proton, 2.8MeV) and (iii) to evaluate irradiation dose for quantitative analysis. It will be advantageous to many researchers since it is very simple and save time during the sample preparation. However, there are some disadvantages in the detection range compared to conventional PIXE. The droplet-PIXE system has been applied to a few case studies. Limits of detection with or without any chemical preparation and its superiority or advantages over other PIXE system will be discussed in this paper. Application of the droplet-PIXE system can be expanded in future to other possibilities.5th International Symposium on BioPIX

    Development of Droplet-PIXE System for Environmental Monitoring Samples

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    PIXE is a trace analytical method. During the sample preparation process for PIXE analysis, there may be loss of element due to sublimation or evaporation that must be considered for quantitative analysis. To avoid such problems, suitable droplet PIXE system has been developed for determination of elemental abundances of liquid samples in atmospheric condition. The system has several dripping modes in order to enhance advantage of dripping method over static liquid target method. The droplet-PIXE system has been applied to a few case studies. Its advantages over other PIXE system will be discussed in this paper

    Combined effects of exercise training and D‐allulose intake on endurance capacity in mice

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    Abstract This study investigated the combined effects of exercise training and D‐allulose intake on endurance capacity in mice. Male C57BL/6J mice were fed either a control diet (Con) or a 3% D‐allulose diet (Allu) and further divided into the sedentary (Sed) or exercise training (Ex) groups (Con‐Sed, Con‐Ex, Allu‐Sed, Allu‐Ex, respectively; n = 6–7/group). The mice in the Ex groups were trained on a motor‐driven treadmill 5 days/week for 4 weeks (15–18 m/min, 60 min). After the exercise training period, all mice underwent an exhaustive running test to assess their endurance capacity. At 48 h after the running test, the mice in the Ex groups were subjected to run at 18 m/min for 60 min again. Then the gastrocnemius muscle and liver were sampled immediately after the exercise bout. The running time until exhaustion tended to be higher in the Allu‐Ex than in the Con‐Ex group (p = 0.08). The muscle glycogen content was significantly lower in the Con‐Ex than in the Con‐Sed group and was significantly higher in the Allu‐Ex than in the Con‐Ex group (p < 0.05). Moreover, exercise training increased the phosphorylation levels of adenosine monophosphate‐activated protein kinase (AMPK) in the muscle and liver. The phosphorylation levels of acetyl coenzyme A carboxylase (ACC), a downstream of AMPK, in the muscle and liver were significantly higher in the Allu‐Ex than in the Con‐Sed group (p < 0.05), suggesting that the combination of exercise training and D‐allulose might have activated the AMPK‐ACC signaling pathway, which is associated with fatty acid oxidation in the muscle and liver. Taken together, our data suggested the combination of exercise training and D‐allulose intake as an effective strategy to upregulate endurance capacity in mice. This may be associated with sparing glycogen content and enhancing activation of AMPK‐ACC signaling in the skeletal muscle

    PlexinA1-deficient mice exhibit decreased cell density and augmented oxidative stress in parvalbumin-expressing interneurons in the medial prefrontal cortex

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    PlexinA1 (PlxnA1) is a transmembrane receptor for semaphorins (Semas), a large family of axonal guidance cues vital during neural development. PlxnA1 is expressed in embryonic interneurons, and PlxnA1 deletion in mice leads to less interneurons in the developing cortex. In addition, PlxnA1 has been identified as a schizophrenia susceptibility gene. In our previous study, PlxnA1 knockout (KO) mice under a BALB/cAJ genetic background exhibited significantly increased self-grooming and reduced prepulse inhibition, a reliable phenotype for investigating the neurobiology of schizophrenia. However, the mechanism underlying the abnormal behavior of PlxnA1 KO mice remains unclear. We first confirmed PlxnA1 mRNA expression in parvalbumin-expressing interneurons (PV cells) in the medial prefrontal cortex (mPFC) of adult mice. Immunohistochemical analysis (IHC) showed significantly decreased densities of both GABAergic neurons and PV cells in the mPFC of PlxnA1 KO mice compared with wild type mice (WT). PV cells were found to express molecule interacting with CasL 1 (MICAL1), an effector involved in Sema-Plxn signaling for axon guidance, suggesting MICAL1 and PlxnA1 co-expression in PV cells. Furthermore, IHC analysis of 8-oxo-dG, an oxidative stress marker, revealed significantly increased oxidative stress in PlxnA1-deficient PV cells compared with WT. Thus, increased oxidative stress and decreased PV cell density in the mPFC may determine the onset of PlxnA1 KO mice’s abnormal behavior. Accordingly, deficient PlxnA1-mediated signaling may increase oxidative stress in PV cells, thereby disrupting PV-cell networks in the mPFC and causing abnormal behavior related to neuropsychiatric diseases
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