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1.
Plant Biotechnol J ; 2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38634166

RESUMO

The N6-methyladenosine (m6A) mRNA modification is crucial for plant development and stress responses. In rice, the male sterility resulting from the deficiency of OsFIP37, a core component of m6A methyltransferase complex, emphasizes the significant role of m6A in male fertility. m6A is reversible and can be removed by m6A demethylases. However, whether mRNA m6A demethylase regulates male fertility in rice has remained unknown. Here, we identify the mRNA m6A demethylase OsALKBH9 and demonstrate its involvement in male fertility regulation. Knockout of OsALKBH9 causes male sterility, dependent on its m6A demethylation activity. Cytological analysis reveals defective tapetal programmed cell death (PCD) and excessive accumulation of microspores exine in Osalkbh9-1. Transcriptome analysis of anthers shows up-regulation of genes involved in tapetum development, sporopollenin synthesis, and transport pathways in Osalkbh9-1. Additionally, we demonstrate that OsALKBH9 demethylates the m6A modification in TDR and GAMYB transcripts, which affects the stability of these mRNAs and ultimately leads to excessive accumulation of pollen exine. Our findings highlight the precise control of mRNA m6A modification and reveal the pivotal roles played by OsALKBH9-mediated m6A demethylation in tapetal PCD and pollen exine accumulation in rice.

2.
Geriatr Nurs ; 57: 45-50, 2024 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-38520817

RESUMO

This study investigates the mediating role of activity restriction in the relationship between the fear of falling and health outcomes. This was a cross-sectional study with convenience sampling of 316 nursing home residents. Generalized structural equation modeling was conducted to test the mediating role. The results showed that residents with fear of falling were more likely to restrict their activities and residents who often or always restricted activities reported lower levels of quality of life and higher levels of depression. Severe activity restriction accounted for 75 % of the total effect of fear of falling on quality of life and 69 % of the total effect of fear of falling on depression. Fall prevention efforts should focus on strategies or interventions to reduce residents' excessive fear of falling and promote activity engagement. Physical and social activities will not only prevent future falls but also improve residents' quality of life and mental health.

3.
Artigo em Inglês | MEDLINE | ID: mdl-38551057

RESUMO

AIMS: The aim of this study is to explore the anti-depressant mechanism of Chaihu- Shugan San based on serum medicinal chemistry and network pharmacology methods. BACKGROUND: Depression lacks effective treatments, with current anti-depressants ineffective in 40% of patients. Chaihu-Shugan San (CHSGS) is a well-known traditional Chinese medicine compound to treat depression. However, the chemical components and the underlying mechanisms targeting the liver and brain in the anti-depressant effects of CHSGS need to be elucidated. METHODS: The chemical components of CHSGS in most current network pharmacology studies are screened from TCMSP and TCMID databases. In this study, we investigated the mechanism and material basis of soothing the liver and relieving depression in the treatment of depression by CHSGS based on serum pharmacochemistry. The anti-depressant mechanism of CHSGS was further verified by proteomics and high-throughput data. RESULTS: Through serum medicinal chemistry, we obtained 9 bioactive substances of CHSGS. These ingredients have good human oral bioavailability and are non-toxic. Based on liver ChIPseq data, CHSGS acts on 8 targets specifically localized in the liver, such as FGA, FGB, and FGG. The main contributors to CHSGS soothing the liver qi targets are hesperetin, nobiletin, ferulic acid, naringin and albiflorin. In addition, network pharmacology analysis identified 9 blood components of CHSGS that corresponded to 63 anti-depressant targets in the brain. Among them, nobiletin has the largest number of anti-depressant targets, followed by glycyrrhizic acid, ferulic acid, albiflorin and hesperetin. We also validated the anti-depressant mechanism of CHSGS based on hippocampal proteomics. CHSGS exerts anti-depressant effects on synaptic structure and neuronal function by targeting multiple synapse related proteins. CONCLUSION: This study not only provides a theoretical basis for further expanding the clinical application of CHSGS, but also provides a series of potential lead compounds for the development of depression drugs.

4.
Dig Dis Sci ; 2024 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-38483780

RESUMO

OBJECTIVE: To investigate the safety and prognosis of enbloc or piecemeal removal after enbloc resection of a gastric GIST by comparing the clinical data of endoscopic en block resection and piecemeal removal (EP) and en block resection and complete removal (EC) of gastric GISTs. METHODS: A total of 111 (43 endoscopic piecemeal, and 68 complete removal) patients with gastric GIST's ≥ 2 cm in diameter who underwent endoscopic therapy from January 2016 to June 2020 at the First Affiliated Hospital of Zhengzhou University were retrospectively analyzed. In all cases, it was ensured that the tumor was intact during the resection, however, it was divided into EP group and EC group based on whether the tumor was completely removed or was cut into pieces which were then removed. The patients' recurrence-free survival rate and recurrence-free survival (RFS) were recorded. RESULTS: There was no statistically significant difference in RFS rates between the two groups (P = 0.197). The EP group had relatively high patient age, tumor diameter, risk classification, and operation time. However, there was no statistically significant difference in the number of nuclear fission images, postoperative hospitalization time, postoperative fasting time, complication rate and complication grading between the two groups (P > 0.05). CONCLUSION: Endoscopic piecemeal removal after en block resection of gastric GIST is safe and effective and achieves similar clinical outcomes as complete removal after en block resection.

5.
NPJ Biofilms Microbiomes ; 10(1): 25, 2024 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-38509085

RESUMO

Hyperuricemia (HUA) is a metabolic syndrome caused by abnormal purine metabolism. Although recent studies have noted a relationship between the gut microbiota and gout, whether the microbiota could ameliorate HUA-associated systemic purine metabolism remains unclear. In this study, we constructed a novel model of HUA in geese and investigated the mechanism by which Lactobacillus rhamnosus GG (LGG) could have beneficial effects on HUA. The administration of antibiotics and fecal microbiota transplantation (FMT) experiments were used in this HUA goose model. The effects of LGG and its metabolites on HUA were evaluated in vivo and in vitro. Heterogeneous expression and gene knockout of LGG revealed the mechanism of LGG. Multi-omics analysis revealed that the Lactobacillus genus is associated with changes in purine metabolism in HUA. This study showed that LGG and its metabolites could alleviate HUA through the gut-liver-kidney axis. Whole-genome analysis, heterogeneous expression, and gene knockout of LGG enzymes ABC-type multidrug transport system (ABCT), inosine-uridine nucleoside N-ribohydrolase (iunH), and xanthine permease (pbuX) demonstrated the function of nucleoside degradation in LGG. Multi-omics and a correlation analysis in HUA patients and this goose model revealed that a serum proline deficiency, as well as changes in Collinsella and Lactobacillus, may be associated with the occurrence of HUA. Our findings demonstrated the potential of a goose model of diet-induced HUA, and LGG and proline could be promising therapies for HUA.


Assuntos
Hiperuricemia , Lacticaseibacillus rhamnosus , Humanos , Hiperuricemia/terapia , Nucleosídeos , Lactobacillus , Prolina , Purinas
7.
Phytomedicine ; 128: 155455, 2024 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-38513376

RESUMO

BACKGROUND: Ischemic stroke (IS) is a serious cerebrovascular disease characterized by significantly elevated mortality and disability rates, and the treatments available for this disease are limited. Neuroinflammation and oxidative stress are deemed the major causes of cerebral ischemic injury. N-Cinnamoylpyrrole alkaloids form a small group of natural products from the genus Piper and have not been extensively analyzed pharmacologically. Thus, identifying the effect and mechanism of N-cinnamoylpyrrole-derived alkaloids on IS is worthwhile. PURPOSE: The present research aimed to explore the antineuroinflammatory and antioxidative stress effects of N-cinnamoylpyrrole-derived alkaloids isolated from the genus Piper and to explain the effects and mechanism on IS. METHODS: N-cinnamoylpyrrole-derived alkaloids were isolated from Piper boehmeriaefolium var. tonkinense and Piper sarmentosum and identified by various chromatographic methods. Lipopolysaccharide (LPS)-induced BV-2 microglia and a mouse model intracerebroventricularly injected with LPS were used to evaluate the antineuroinflammatory and antioxidative stress effects. Oxygen‒glucose deprivation/reperfusion (OGD/R) and transient middle cerebral artery occlusion (tMCAO) models were used to evaluate the effect of PB-1 on IS. To elucidate the fundamental mechanism, the functional target of PB-1 was identified by affinity-based protein profiling (ABPP) strategy and verified by cellular thermal shift assay (CETSA), drug affinity responsive target stability (DARTS), and circular dichroism (CD) analyses. The effect of PB-1 on the NF-κB and NRF2 signaling pathways was subsequently evaluated via western blotting and immunofluorescence staining. RESULTS: The results showed that N-cinnamoylpyrrole-derived alkaloids significantly affected neuroinflammation and oxidative stress. The representative compound, PB-1 not only inhibited neuroinflammation and oxidative stress induced by LPS or OGD/R insult, but also alleviated cerebral ischemic injury induced by tMCAO. Further molecular mechanism research found that PB-1 promoted antineuroinflammatory and antioxidative stress activities via the NF-κB and NRF2 signaling pathways by targeting eEF1A1. CONCLUSION: Our research initially unveiled that the therapeutic impact of PB-1 on cerebral ischemic injury might rely on its ability to target eEF1A1, leading to antineuroinflammatory and antioxidative stress effects. The novel discovery highlights eEF1A1 as a potential target for IS treatment and shows that PB-1, as a lead compound that targets eEF1A1, may be a promising therapeutic agent for IS.

8.
PLoS Pathog ; 20(2): e1011981, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38354122

RESUMO

Lysosomes are acidic organelles that mediate the degradation and recycling of cellular waste materials. Damage to lysosomes can cause lysosomal membrane permeabilization (LMP) and trigger different types of cell death, including apoptosis. Newcastle disease virus (NDV) can naturally infect most birds. Additionally, it serves as a promising oncolytic virus known for its effective infection of tumor cells and induction of intensive apoptotic responses. However, the involvement of lysosomes in NDV-induced apoptosis remains poorly understood. Here, we demonstrate that NDV infection profoundly triggers LMP, leading to the translocation of cathepsin B and D and subsequent mitochondria-dependent apoptosis in various tumor and avian cells. Notably, the released cathepsin B and D exacerbate NDV-induced LMP by inducing the generation of reactive oxygen species. Additionally, we uncover that the viral Hemagglutinin neuraminidase (HN) protein induces the deglycosylation and degradation of lysosome-associated membrane protein 1 (LAMP1) and LAMP2 dependent on its sialidase activity, which finally contributes to NDV-induced LMP and cellular apoptosis. Overall, our findings elucidate the role of LMP in NDV-induced cell apoptosis and provide novel insights into the function of HN during NDV-induced LMP, which provide innovative approaches for the development of NDV-based oncolytic agents.


Assuntos
Proteína HN , Vírus da Doença de Newcastle , Animais , Vírus da Doença de Newcastle/metabolismo , Proteína HN/metabolismo , Catepsina B , Apoptose , Lisossomos/metabolismo
9.
Eur J Anaesthesiol ; 41(4): 305-313, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38298060

RESUMO

BACKGROUND: Tracheal injuries, vocal cord injuries, sore throat and hoarseness are common complications of double-lumen tube (DLT) intubation. OBJECTIVE: This study aimed to evaluate the effects of 'video double-lumen tubes' (VDLTs) on intubation complications in patients undergoing thoracic surgery. DESIGN: A randomised controlled study. SETTINGT: Xuzhou Cancer Hospital, Xuzhou, China, from January 2023 to June 2023. PATIENTS: One hundred eighty-two patients undergoing elective thoracic surgery with one-lung ventilation were randomised into two groups: 90 in the DLT group and 92 in the VDLT group. INTERVENTION: VDLT was selected for intubation in the VDLT group, and DLT was selected for intubation in the DLT group. A fibreoptic bronchoscope (FOB) was used to record tracheal and vocal cord injuries. MAIN OUTCOME MEASURES: The primary outcomes were the incidence of moderate-to-severe tracheal injury and the incidence of vocal cord injury. The secondary outcomes included the incidence and severity of postoperative 24 and 48 h sore throat and hoarseness. RESULTS: The incidence of moderate-to-severe tracheal injury was 32/90 (35.6%) in the DLT group, and 45/92 (48.9%) in the VDLT group ( P  = 0.077; relative risk 1.38, 95% CI, 0.97 to 1.95). The incidence of vocal cord injury was 31/90 (34.4%) and 34/92 (37%) in the DLT and VDLT groups, respectively ( P  = 0.449). The incidence of postoperative 24 h sore throat and hoarseness was significantly higher in the VDLT group than in the DLT group (for sore throat: P  = 0.032, relative risk 1.63, 95% CI, 1.03 to 2.57; for hoarseness: P  = 0.018, relative risk 1.48, 95% CI, 1.06 to 2.06). CONCLUSION: There was no statistically significant difference in the incidence of moderate-to-severe tracheal injury and vocal cord injury between DLTs and VDLTs. While improving the first-attempt success rate, intubation with VDLT increased the incidence of postoperative 24 h sore throat and hoarseness. TRIAL REGISTRATION: Chinese Clinical Trial Registry identifier: ChiCTR2300067348.


Assuntos
Faringite , Cirurgia Torácica , Procedimentos Cirúrgicos Torácicos , Humanos , Rouquidão/diagnóstico , Rouquidão/epidemiologia , Rouquidão/etiologia , Procedimentos Cirúrgicos Torácicos/efeitos adversos , Broncoscópios , Faringite/epidemiologia , Faringite/etiologia
10.
Cell Host Microbe ; 32(3): 366-381.e9, 2024 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-38412863

RESUMO

Hyperuricemia induces inflammatory arthritis and accelerates the progression of renal and cardiovascular diseases. Gut microbiota has been linked to the development of hyperuricemia through unclear mechanisms. Here, we show that the abundance and centrality of Alistipes indistinctus are depleted in subjects with hyperuricemia. Integrative metagenomic and metabolomic analysis identified hippuric acid as the key microbial effector that mediates the uric-acid-lowering effect of A. indistinctus. Mechanistically, A. indistinctus-derived hippuric acid enhances the binding of peroxisome-proliferator-activated receptor γ (PPARγ) to the promoter of ATP-binding cassette subfamily G member 2 (ABCG2), which in turn boosts intestinal urate excretion. To facilitate this enhanced excretion, hippuric acid also promotes ABCG2 localization to the brush border membranes in a PDZ-domain-containing 1 (PDZK1)-dependent manner. These findings indicate that A. indistinctus and hippuric acid promote intestinal urate excretion and offer insights into microbiota-host crosstalk in the maintenance of uric acid homeostasis.


Assuntos
Bacteroidetes , Hipuratos , Hiperuricemia , Humanos , Hiperuricemia/metabolismo , Ácido Úrico/metabolismo , Intestinos , Transportadores de Cassetes de Ligação de ATP/metabolismo
11.
PLoS Pathog ; 20(2): e1012027, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38377149

RESUMO

Newcastle disease virus (NDV) has been extensively studied as a promising oncolytic virus for killing tumor cells in vitro and in vivo in clinical trials. However, the viral components that regulate the oncolytic activity of NDV remain incompletely understood. In this study, we systematically compared the replication ability of different NDV genotypes in various tumor cells and identified NP protein determines the oncolytic activity of NDV. On the one hand, NDV strains with phenylalanine (F) at the 450th amino acid position of the NP protein (450th-F-NP) exhibit a loss of oncolytic activity. This phenotype is predominantly associated with genotype VII NDVs. In contrast, the NP protein with a leucine amino acid at this site in other genotypes (450th-L-NP) can facilitate the loading of viral mRNA onto ribosomes more effectively than 450th-F-NP. On the other hand, the NP protein from NDV strains that exhibit strong oncogenicity interacts with eIF4A1 within its 366-489 amino acid region, leading to the inhibition of cellular mRNA translation with a complex 5' UTR structure. Our study provide mechanistic insights into how highly oncolytic NDV strains selectively promote the translation of viral mRNA and will also facilitate the screening of oncolytic strains for oncolytic therapy.


Assuntos
Vírus da Doença de Newcastle , Vírus Oncolíticos , Animais , Vírus da Doença de Newcastle/genética , Aminoácidos , Leucina , Vírus Oncolíticos/genética , RNA Mensageiro/genética , Biossíntese de Proteínas
13.
Genes (Basel) ; 15(1)2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-38254987

RESUMO

Rehmannia chingii is an important medicinal plant with immense value in scientific research. However, its mitochondrial genome (mitogenome) has not yet been characterized. Herein, based on whole-genome Illumina short reads and PacBio HiFi reads, we obtained the complete mitogenome of R. chingii through a de novo assembly strategy. We carried out comparative genomic analyses and found that, in comparison with the plastid genome (plastome) showing a high degree of structural conservation, the R. chingii mitogenome structure is relatively complex, showing an intricate ring structure with 16 connections, owing to five repetitive sequences. The R. chingii mitogenome was 783,161 bp with a GC content of 44.8% and contained 77 genes, comprising 47 protein-coding genes (CDS), 27 tRNA genes, and 3 rRNA genes. We counted 579 RNA editing events in 47 CDS and 12,828 codons in all CDSs of the R. chingii mitogenome. Furthermore, 24 unique sequence transfer fragments were found between the mitogenome and plastome, comprising 8 mitogenome CDS genes and 16 plastome CDS genes, corresponding to 2.39% of the R. chingii mitogenome. Mitogenomes had shorter but more collinear regions, evidenced by a comparison of the organelles of non-parasitic R. chingii, hemiparasitic Pedicularis chinensis, and holoparasitic Aeginetia indica in the Orobanchaceae family. Moreover, from non-parasitic to holoparasitic species, the genome size in the mitogenomes of Orobanchaceae species did not decrease gradually. Instead, the smallest mitogenome was found in the hemiparasitic species P. chinensis, with a size of 225,612 bp. The findings fill the gap in the mitogenome research of the medicinal plant R. chingii, promote the progress of the organelle genome research of the Orobanchaceae family, and provide clues for molecular breeding.


Assuntos
Genoma Mitocondrial , Eritrodermia Ictiosiforme Congênita , Erros Inatos do Metabolismo Lipídico , Doenças Musculares , Orobanchaceae , Rehmannia , Genoma Mitocondrial/genética , Hibridização Genômica Comparativa
14.
Zhen Ci Yan Jiu ; 49(1): 47-56, 2024 Jan 25.
Artigo em Inglês, Chinês | MEDLINE | ID: mdl-38239138

RESUMO

OBJECTIVES: To observe the effect of moxibustion intervention on the hypothalamus-spinal cord-colon axis of rats with irritable bowel syndrome with diarrhea (IBS-D) and explore the mechanism of moxibustion in improving visceral hypersensitivity in rats with IBS-D. METHODS: A total of 36 SD rats were randomly divided into normal, model, and moxibustion groups, with 12 rats in each group. The IBS-D model was established by maternal separation + acetic acid stimulation + chronic restraint. Rats of the moxibustion group received bilateral moxibustion on "Tianshu" (ST25) and "Shangjuxu" (ST37) for 15 min, once a day for 7 consecutive days. The body weight, loose stool rate, and minimum threshold volume of abdominal withdrawal reflex (AWR) were measured before and after moxibustion intervention, respectively. The histopathological changes in the colon tissue were observed after HE staining. The number of colonic mucosal mast cells (MCs) was measured by toluidine blue staining. The activation of MCs was determined by tryptase positive expression level and examined by immunohistochemical staining. The content, protein and mRNA expression levels and positive expression levels of corticotropin releasing factor (CRF), substance P (SP), and calcitonin gene-related peptide (CGRP) in the hypothalamus, spinal cord and colon tissues were measured by ELISA, Western blot, real-time fluorescent quantitative PCR and immunofluorescence staining, respectively. RESULTS: Compared with the normal group, the loose stool rate was increased (P<0.01);the body weight and minimum threshold volume of AWR were decreased (P<0.01);the inflammatory infiltration of colon tissues was obvious;the number of MCs and positive expression level of tryptase in the colon tissue were increased (P<0.01);the contents, positive expression le-vels, protein and mRNA expression levels of CRF, SP and CGRP in the hypothalamus, spinal cord and colon tissues were increased (P<0.01, P<0.05) in the model group. After the intervention, compared with the model group, all these indicators showed opposite trends (P<0.01, P<0.05) in the moxibustion group. CONCLUSIONS: Moxibustion can improve visceral hypersensitivity in rats with IBS-D, and its mechanism may be related to regulating the hypothalamic-spinal-colon axis to reduce the release of CRF, SP and CGRP, and thus to inhibite MC in colon tissue.


Assuntos
Síndrome do Intestino Irritável , Moxibustão , Ratos , Animais , Síndrome do Intestino Irritável/genética , Síndrome do Intestino Irritável/terapia , Síndrome do Intestino Irritável/metabolismo , Ratos Sprague-Dawley , Hormônio Liberador da Corticotropina/metabolismo , Triptases/metabolismo , Peptídeo Relacionado com Gene de Calcitonina/metabolismo , Privação Materna , Diarreia/genética , Diarreia/terapia , Hipotálamo/metabolismo , Substância P/metabolismo , Medula Espinal , Peso Corporal , RNA Mensageiro/metabolismo
15.
J Biochem Mol Toxicol ; 38(1): e23581, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38044485

RESUMO

Colorectal cancer (CRC) is a common digestive tract tumor with a high incidence and a poor prognosis. Traditional chemotherapy drugs are usually accompanied by unpleasant side effects, highlighting the importance of exploring new adjunctive drugs. In this study, we aimed to explore the role of ursolic acid (UA) in CRC cells. Specifically, HT-29 cells were treated with UA at different concentrations (10, 20, 30, and 40 µM), and the expression of miR-140-5p, tumor growth factor-ß3 (TGF-ß3), ß-catenin, and cyclin D1 was determined by real-time quantitative PCR. The cell cycle and apoptosis were checked by flow cytometry, and cell proliferation was detected by Cell Counting Kit-8 assay. The HT-29 cell model was established through overexpression (miR-140-5p mimics) and interference (miR-140-5p inhibitor) of miR-140-5p. Western blot was used to detect the protein expression of TGF-ß3. We found that UA could inhibit the proliferation of HT-29 cells, block cells in the G1 phase, and promote cell apoptosis. After UA treatment, the expression of miR-140-5p increased and TGF-ß3 decreased. Notably, miR-140-5p downregulated the expression of TGF-ß3, while the overexpression of miR-140-5p exerted a similar function to UA in HT-29 cells. Additionally, the messenger RNA expression of TGF-ß3, ß-catenin, and cyclin D1 was decreased in HT-29 cells after UA treatment. In conclusion, UA inhibited CRC cell proliferation and cell cycle and promoted apoptosis by regulating the miR-140-5p/TGF-ß3 axis, which may be related to the inhibition of Wnt/ß-catenin signaling pathway.


Assuntos
Neoplasias Colorretais , MicroRNAs , Humanos , beta Catenina/metabolismo , MicroRNAs/metabolismo , Linhagem Celular Tumoral , Ciclina D1/genética , Ciclina D1/metabolismo , Fator de Crescimento Transformador beta3/genética , Fator de Crescimento Transformador beta3/metabolismo , Regulação para Baixo , Proliferação de Células/genética , Peptídeos e Proteínas de Sinalização Intercelular/genética , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/genética , Neoplasias Colorretais/metabolismo , Regulação Neoplásica da Expressão Gênica
17.
Plant J ; 117(1): 177-192, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37797086

RESUMO

'Living fossils', that is, ancient lineages of low taxonomic diversity, represent an exceptional evolutionary heritage, yet we know little about how demographic history and deleterious mutation load have affected their long-term survival and extinction risk. We performed whole-genome sequencing and population genomic analyses on Dipteronia sinensis and D. dyeriana, two East Asian Tertiary relict trees. We found large-scale genome reorganizations and identified species-specific genes under positive selection that are likely involved in adaptation. Our demographic analyses suggest that the wider-ranged D. sinensis repeatedly recovered from population bottlenecks over late Tertiary/Quaternary periods of adverse climate conditions, while the population size of the narrow-ranged D. dyeriana steadily decreased since the late Miocene, especially after the Last Glacial Maximum (LGM). We conclude that the efficient purging of deleterious mutations in D. sinensis facilitated its survival and repeated demographic recovery. By contrast, in D. dyeriana, increased genetic drift and reduced selection efficacy, due to recent severe population bottlenecks and a likely preponderance of vegetative propagation, resulted in fixation of strongly deleterious mutations, reduced fitness, and continuous population decline, with likely detrimental consequences for the species' future viability and adaptive potential. Overall, our findings highlight the significant impact of demographic history on levels of accumulation and purging of putatively deleterious mutations that likely determine the long-term survival and extinction risk of Tertiary relict trees.


Assuntos
Fósseis , Endogamia , Árvores , Animais , Variação Genética , Metagenômica , Mutação , Árvores/genética
18.
Langmuir ; 40(1): 744-750, 2024 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-38103033

RESUMO

To explore, highly active electrocatalysts are essential for water splitting materials. Polyoxometalates (POMs) have drawn interesting attention in recent years due to their abundant structure and unique electrocatalytic properties. In this study, by using a POM-based precursor Co2Mo10, novel bimetallic sulfide (CoS2-MoS2) nanocomposites are rationally designed and synthesized under hydrothermal conditions. The incorporation of Co2+ to the host electrocatalyst could effectively increase the exposure of active sites of MoS2. Compared to pure MoS2, the CoS2-MoS2 nanocomposite exhibited a perfect hydrogen evolution reaction (HER) ability, for it merely requires overpotentials of 120 and 153 mV for 10 mA cm-2 working current density toward the HER in 1 M KOH and 0.5 M H2SO4 electrolyte systems, respectively. Additionally, the nanocomposite exhibited outstanding chemical stability and long-term durability. This study presents a novel strategy that utilizes POMs to enrich the exposed edge sites of MoS2, resulting in the preparation of efficient electrocatalysts.

19.
Artigo em Inglês | MEDLINE | ID: mdl-38060359

RESUMO

In the design of prosthetic hand fingers, achieving human-like movement while meeting anthropomorphic demands such as appearance, size, and lightweight is quite challenging. Human finger movement involves two distinct motion characters during natural reach-and-grasp tasks: consistency in the reaching stage and adaptability in the grasping stage. The former one enhances grasp stability and reduces control complexity; the latter one promotes the adaptability of finger to various objects. However, conventional tendon-driven prosthetic finger designs typically incorporate bulky actuation modules or complex tendon routes to reconcile the consistency and adaptability. In contrast, we propose a novel friction clutch consisting of a single tendon and slider, which is simple and compact enough to be configurated within the metacarpal bone. Through tactfully exploiting the friction force to balance the gravity effect on each phalanx during finger motion, this design effectively combines both consistency and adaptability. As a result, the prosthetic finger can maintain consistent motion unaffected by any spatial posture during reaching, execute adaptive motion during grasping, and automatically switch between them, resulting in human-like reach-and-grasp movements. Additionally, the proposed finger achieves a highly anthropomorphic design, weighing only 18.9 g and possessing the same size as an adult's middle finger. Finally, a series of experiments validate the theoretical effectiveness and motion performance of the proposed design. Remarkably, the mechanical principle of the proposed friction clutch is beneficial to achieve highly anthropomorphic design, providing not only a new strategy to prosthetic hand design but also great potential in hand rehabilitation.


Assuntos
Dedos , Mãos , Adulto , Humanos , Fricção , Movimento , Força da Mão
20.
Cancers (Basel) ; 15(24)2023 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-38136320

RESUMO

At present, multiple myeloma (MM) is still an essentially incurable hematologic malignancy. Although BCMA-targeted therapies have achieved remarkable results, BCMA levels were found to be downregulated in patients with MM who relapsed after these treatments. Therefore, the search for other antigens specific to MM has become a priority. Independently of BCMA expression, G-protein-coupled receptor family C group 5 member D (GPRC5D) is mainly expressed in the plasma cells of MM patients, while it is expressed in a limited number of normal tissues. Combining MM-specific antigen GPRC5D and T-cell-mediated therapies would be a promising therapeutic strategy for MM. Recently, we constructed a new anti-GPRC5D × anti-CD3 T-cell-engaging bispecific antibody (TCB), BR109, which was capable of binding to human GPRC5D and human CD3ε. Moreover, BR109 was proven to have relatively good stability and antitumor activity. BR109 could specifically trigger T-cell-mediated cytotoxicity against many GPRC5D-positive MM cells in vitro. Meanwhile, antitumor activity was demonstrated in MM cell line xenograft mouse models with human immune cell reconstitution. These preclinical studies have formed a solid foundation for the evaluation of MM treatment efficacy in clinical trials.

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