Aim
The effect of eustasy driven by climatic oscillations on species diversification across the East China Sea (ECS) remains unclear. In this study, Machilus thunbergii (红楠, red nanmu in Chinese) was ...used as a model species to determine whether the ECS acted as either a “species pump” or “species vacuum” during the Pleistocene.
Locations
Eastern China, and southern and central Japan.
Taxon
Lauraceae.
Methods
Ecological niche modelling was employed to predict the potential distribution of M. thunbergii during the Last Glacial Maximum (LGM) and the last interglacial period. Nuclear microsatellite and chloroplast markers were used to reveal the phylogeographic pattern and infer the population history of 33 M. thunbergii populations.
Results
The ecological niche models suggested that the ECS provided potentially suitable habitats for M. thunbergii during the LGM. A sharp change in cpDNA haplotypes was found along the eastern China coasts, while microsatellites revealed a clinal pattern for genetic composition from eastern China to central Japan. The divergent lineages formed an admixture on the Zhoushan Archipelago of China and Kyushu Island of Japan. The estimated divergent and admixture times were c. 68 kyr and c. 15 kyr, corresponding to the periods where there were rising sea levels after the MIS4 glaciation and falling sea levels during the LGM, respectively.
Main conclusions
Machilus thunbergii probably underwent alternating population isolation during interglacial periods and connection during glacial maxima across the ECS, but such periodicity of isolation and connection seems not to have promoted diversification as suggested by the species pump hypothesis. Incipient divergence has been periodically wiped out due to frequent coalescence, rendering the ECS more like a “species vacuum”, particularly for species with relatively long generation lengths.
Role of lipocalin 2 in stroke Zhao, Ruo-Yu; Wei, Peng-Ju; Sun, Xin ...
Neurobiology of disease,
April 2023, 2023-04-00, 20230401, 2023-04-01, Letnik:
179
Journal Article
Recenzirano
Odprti dostop
Stroke is the second leading cause of death worldwide; however, the treatment choices available to neurologists are limited in clinical practice. Lipocalin 2 (LCN2) is a secreted protein, belonging ...to the lipocalin superfamily, with multiple biological functions in mediating innate immune response, inflammatory response, iron-homeostasis, cell migration and differentiation, energy metabolism, and other processes in the body. LCN2 is expressed at low levels in the brain under normal physiological conditions, but its expression is significantly up-regulated in multiple acute stimulations and chronic pathologies. An up-regulation of LCN2 has been found in the blood/cerebrospinal fluid of patients with ischemic/hemorrhagic stroke, and could serve as a potential biomarker for the prediction of the severity of acute stroke. LCN2 activates reactive astrocytes and microglia, promotes neutrophil infiltration, amplifies post-stroke inflammation, promotes blood–brain barrier disruption, white matter injury, and neuronal death. Moreover, LCN2 is involved in brain injury induced by thrombin and erythrocyte lysates, as well as microvascular thrombosis after hemorrhage. In this paper, we review the role of LCN2 in the pathological processes of ischemic stroke; intracerebral hemorrhage; subarachnoid hemorrhage; and stroke-related brain diseases, such as vascular dementia and post-stroke depression, and their underlying mechanisms. We hope that this review will help elucidate the value of LCN2 as a therapeutic target in stroke.
•Increased lipocalin 2 (LCN2) occurs in brains under pathological conditions.•LCN2 has potential predictive value for acute stroke severity.•We review the role of LCN2 in the pathology of stroke and related disorders.•The findings will help elucidate the therapeutic target value of LCN2 in stroke.
A novel and convenient protocol for the difluoroalkylation‐thiolation of alkenes catalyzed by Cu/Na2S2O5 system has been developed. This reaction was carried out using readily available starting ...materials under mild conditions, wherein the C−C and C−S bonds simultaneously were constructed smoothly. The reaction features broad substrate scope of alkenes and disulfides, good functional group tolerance, and good to excellent yields with high selectivity.
We report an efficient protocol for the difluoroalkylation‐thiolation of alkenes catalyzed by Cu/Na2S2O5 system with disulfides as a sulfur source. This reaction allows a variety of alkenes and disulfides, wherein the new C−C and C−S bonds were simultaneously constructed.
The establishment of water quality criteria (WQC) for copper (Cu) was used as the basis for an ecological risk assessment of marine Cu pollution in Liaodong Bay, China. Published ecotoxicity data for ...Cu were obtained and supplemented with the results of acute Cu toxicity tests. The marine WQC for Cu in Liaodong Bay was developed using a species sensitivity distribution method with a safety factor of 2.0 and the USEPA acute-to-chronic ratio method. The ecological risk of Cu in Liaodong Bay was assessed by comparing the seawater Cu concentrations with the developed WQC. The results of this study showed that the acute and chronic Cu concentrations in Liaodong Bay were 3.31 and 2.18 μg/L, respectively. Comparison of the WQC to Cu concentrations in the bay resulted in risk quotients slightly >1.0 and typically ≤2.0. These data suggest that certain organisms in Liaodong Bay are at risk. These results can assist in the development of a pollution control management approach for the bay.
•Use SSD method and the FACR method to derive the sea WQCs of copper in Liaodong Bay•Use the RQ method and overlapping area method to assess the ecological risk of copper in Liaodong Bay•The SWQC and LWQC for copper in Liaodong Bay were 3.31 and 2.18 μg/L.•The ecological environmental risk of copper to aquatic species in Liaodong Bay showed an overall increasing trend.
Growing evidences suggest that cancer stem cells exhibit many molecular characteristics and phenotypes similar to their ancestral progenitor cells. In the present study, human embryonic stem cells ...are induced to differentiate into hepatocytes along hepatic lineages to mimic liver development in vitro. A liver progenitor specific gene, RALY RNA binding protein like (RALYL), is identified. RALYL expression is associated with poor prognosis, poor differentiation, and metastasis in clinical HCC patients. Functional studies reveal that RALYL could promote HCC tumorigenicity, self-renewal, chemoresistance, and metastasis. Moreover, molecular mechanism studies show that RALYL could upregulate TGF-β2 mRNA stability by decreasing N6-methyladenosine (m
A) modification. TGF-β signaling and the subsequent PI3K/AKT and STAT3 pathways, upregulated by RALYL, contribute to the enhancement of HCC stemness. Collectively, RALYL is a liver progenitor specific gene and regulates HCC stemness by sustaining TGF-β2 mRNA stability. These findings may inspire precise therapeutic strategies for HCC.
Plant leaves can retain atmospheric particulate matter (PM) and thus alleviate air pollution. Herein, four plant species (Cerasus. serrulata, H. syriacus, H. tuberosus, and E. japonicus) from the ...central part of Shanxi Province, China, were investigated to analyse the dynamic changes in their PM retention capacity and grain size over five periods. The relationship between leaf morphological characteristics (leaf size and leaf surface microstructure) and dynamic changes were discussed in PM retention, revealing the influence of leaf morphological characteristics on the amount of PM retention and its composition. The results showed that amount and grain sizes of the retained PM differed significantly among the various studied species; however, the trends in PM retention of different species in the time series were the same. The grain size distributions of PM from the four species displayed a bimodal distribution, in which the main peak distribution range was 5-60 μm and the secondary peak distribution range was 0.4-1 μm. Leaves of smaller sizes and those with rough surfaces had a high PM retention capacity. Leaves with deep grooves are conductive to retaining PM
2.5
and PM
2.5-10
, while leaves with hair are conductive to retaining PM
>10
. Therefore, the morphological characteristics of leaves should be considered when selecting the use of plant species to alleviate air pollution.
Highlights
Dynamics of PM retention capacity and grain size distributions of four plant species were analysed.
Grain size distributions of PM retained on leaves had a bimodal distribution.
Small leaves with grooves or hair are conductive to PM retention.
Grooves are conductive to fine PM retention while hairs are conductive to coarse PM retention.
The thriving 5G communication technology leads to the high demand for EMI shielding materials and thermal management materials. Particularly, portable thermal‐sensitive electronic devices have more ...stringent requirements for thermal insulation performances. In most cases, ultrathin EMI shielding materials integrated with ultralow thermal conductivity are not easy to be achieved. To overcome this obstacle, dual protective porous composite films based on Ti3C2Tx MXene and polyimide are fabricated by sacrificing polymethyl methacrylate (PMMA) templates. By optimizing the contact thermal resistance and Kapitza resistance, the composite film presents superior thermal insulation performances with a thermal conductivity of 0.0136 W m−1 K−1. Moreover, the hybrid porous film maintains superior EMI shielding effectiveness of 63.0 dB and high SSE/t of 31651.2 dB cm2 g−1. Nevertheless, the excellent active and passive heating ability based on Joule heating and photothermal conversion makes the composite film an ideal portable material for thermal management. This work sheds light on designing thermal management materials and EMI shielding materials for cutting‐edge electronic devices.
This work presents a convenient way for fabricating heat insulation and EMI shielding composite films with ultralow thickness. Based on the low thermal conductivity, the composite films also present excellent Joule heating performances and photothermal conversion performances.
The development of antinociceptive tolerance following repetitive administration of opioid analgesics significantly hinders their clinical use. Evidence has accumulated indicating that microglia ...within the spinal cord plays a critical role in morphine tolerance. The inhibitor of microglia is effective to attenuate the tolerance; however, the mechanism is not fully understood. Our present study investigated the effects and possible mechanism of a natural product procyanidins in improving morphine tolerance via its specific inhibition on NOD-like receptor protein3 (NLRP3) inflammasome in microglia.
CD-1 mice were used for tail-flick test to evaluate the degree of pain. The microglial cell line BV-2 was used to investigate the effects and the mechanism of procyanidins. Reactive oxygen species (ROS) produced from BV-2 cells was evaluated by flow cytometry. Cell signaling was measured by western blot assay and immunofluorescence assay.
Co-administration of procyanidins with morphine potentiated its antinociception effect and attenuated the development of acute and chronic morphine tolerance. Procyanidins also inhibited morphine-induced increase of interleukin-1β and activation of NOD-like receptor protein3 (NLRP3) inflammasome. Furthermore, procyanidins decreased the phosphorylation of p38 mitogen-activated protein kinase, inhibited the translocation of nuclear factor-κB (NF-κB), and suppressed the level of reactive oxygen species in microglia.
Procyanidins suppresses morphine-induced activation of NLRP3 inflammasome and inflammatory responses in microglia, and thus resulting in significant attenuation of morphine antinociceptive tolerance.
Mitochondrial dysfunction has been widely reported in several neurodegenerative disorders, including in the brains of patients with Alzheimer's disease (AD), Parkinson's disease, and Huntington ...disease. An increasing number of studies have implicated altered glucose and energy metabolism in patients with AD. There is compelling evidence of abnormalities in some of the key mitochondrial enzymes involved in glucose metabolism, including the pyruvate dehydrogenase and α-ketoglutarate dehydrogenase complexes, which play a great significance role in the pathogenesis of AD. Changes in some of the enzyme activities of the mitochondria found in AD have been linked with the pathology of amyloid-β (Aβ). This review highlights the role of mitochondrial function in the production and clearance of Aβ and how the pathology of Aβ leads to a decrease in energy metabolism by affecting mitochondrial function.
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