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1.
Acta Pharmacol Sin ; 45(7): 1349-1365, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38504011

RESUMO

Ischemic stroke is a major cause of disability and death worldwide, and its management requires urgent attention. Previous studies have shown that vagus nerve stimulation (VNS) exerts neuroprotection in ischemic stroke by inhibiting neuroinflammation and apoptosis. In this study, we evaluated the timing for VNS intervention in ischemic stroke, and the underlying mechanisms  of VNS-induced neuroprotection. Mice were subjected to transient middle cerebral artery occlusion (tMCAO) for 60 min. The left vagus nerve at cervical level was exposed and attached to an electrode connected to a low-frequency electrical stimulator. Vagus nerve stimulation (VNS) was given for 60 min before, during and after tMCAO (Pre-VNS, Dur-VNS, Post-VNS). Neurological function was assessed 24 h after reperfusion. We found that all the three VNS significantly protected against the tMCAO-induced injury evidenced by improved neurological function and reduced infarct volume. Moreover, the Pre-VNS was the most effective against the ischemic injury. We found that tMCAO activated microglia in the ischemic core and penumbra regions of the brain, followed by the NLRP3 inflammasome activation-induced neuroinflammation, which finally triggered neuronal death. VNS treatment preserved α7nAChR expression in the penumbra regions, inhibited NLRP3 inflammasome activation and ensuing neuroinflammation, rescuing cerebral neurons. The role of α7nAChR in microglial NLRP3 inflammasome activation in ischemic stroke was further validated using genetic manipulations, including Chrna7 knockout mice and microglial Chrna7 overexpression mice, as well as pharmacological interventions using the α7nAChR inhibitor methyllycaconitine and agonist PNU-282987. Collectively, this study demonstrates the potential of VNS as a safe and effective strategy to treat ischemic stroke, and presents a new approach targeting microglial NLRP3 inflammasome, which might be therapeutic for other inflammation-related diseases.


Assuntos
Infarto da Artéria Cerebral Média , Inflamassomos , AVC Isquêmico , Camundongos Endogâmicos C57BL , Microglia , Proteína 3 que Contém Domínio de Pirina da Família NLR , Estimulação do Nervo Vago , Receptor Nicotínico de Acetilcolina alfa7 , Animais , Receptor Nicotínico de Acetilcolina alfa7/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Estimulação do Nervo Vago/métodos , AVC Isquêmico/metabolismo , Microglia/metabolismo , Camundongos , Inflamassomos/metabolismo , Masculino , Infarto da Artéria Cerebral Média/terapia , Neuroproteção , Camundongos Knockout
2.
Proc Natl Acad Sci U S A ; 118(20)2021 05 18.
Artigo em Inglês | MEDLINE | ID: mdl-33941644

RESUMO

How coniferous forests evolved in the Northern Hemisphere remains largely unknown. Unlike most groups of organisms that generally follow a latitudinal diversity gradient, most conifer species in the Northern Hemisphere are distributed in mountainous areas at middle latitudes. It is of great interest to know whether the midlatitude region has been an evolutionary cradle or museum for conifers and how evolutionary and ecological factors have driven their spatiotemporal evolution. Here, we investigated the macroevolution of Pinus, the largest conifer genus and characteristic of northern temperate coniferous forests, based on nearly complete species sampling. Using 1,662 genes from transcriptome sequences, we reconstructed a robust species phylogeny and reestimated divergence times of global pines. We found that ∼90% of extant pine species originated in the Miocene in sharp contrast to the ancient origin of Pinus, indicating a Neogene rediversification. Surprisingly, species at middle latitudes are much older than those at other latitudes. This finding, coupled with net diversification rate analysis, indicates that the midlatitude region has provided an evolutionary museum for global pines. Analyses of 31 environmental variables, together with a comparison of evolutionary rates of niche and phenotypic traits with a net diversification rate, found that topography played a primary role in pine diversification, and the aridity index was decisive for the niche rate shift. Moreover, fire has forced diversification and adaptive evolution of Pinus Our study highlights the importance of integrating phylogenomic and ecological approaches to address evolution of biological groups at the global scale.


Assuntos
Ecologia/métodos , Ecossistema , Evolução Molecular , Filogenia , Pinus/genética , Análise Espaço-Temporal , Perfilação da Expressão Gênica/métodos , Regulação da Expressão Gênica de Plantas , Especiação Genética , Variação Genética , Geografia , Fenótipo , Pinus/anatomia & histologia , Pinus/classificação , Especificidade da Espécie , Fatores de Tempo
3.
Mol Biol Evol ; 39(1)2022 01 07.
Artigo em Inglês | MEDLINE | ID: mdl-34718707

RESUMO

Evolutionary radiation is a widely recognized mode of species diversification, but its underlying mechanisms have not been unambiguously resolved for species-rich cosmopolitan plant genera. In particular, it remains largely unknown how biological and environmental factors have jointly driven its occurrence in specific regions. Here, we use Rhododendron, the largest genus of woody plants in the Northern Hemisphere, to investigate how geographic and climatic factors, as well as functional traits, worked together to trigger plant evolutionary radiations and shape the global patterns of species richness based on a solid species phylogeny. Using 3,437 orthologous nuclear genes, we reconstructed the first highly supported and dated backbone phylogeny of Rhododendron comprising 200 species that represent all subgenera, sections, and nearly all multispecies subsections, and found that most extant species originated by evolutionary radiations when the genus migrated southward from circumboreal areas to tropical/subtropical mountains, showing rapid increases of both net diversification rate and evolutionary rate of environmental factors in the Miocene. We also found that the geographically uneven diversification of Rhododendron led to a much higher diversity in Asia than in other continents, which was mainly driven by two environmental variables, that is, elevation range and annual precipitation, and were further strengthened by the adaptation of leaf functional traits. Our study provides a good example of integrating phylogenomic and ecological analyses in deciphering the mechanisms of plant evolutionary radiations, and sheds new light on how the intensification of the Asian monsoon has driven evolutionary radiations in large plant genera of the Himalaya-Hengduan Mountains.


Assuntos
Rhododendron , Ásia , Evolução Biológica , Filogenia , Plantas , Rhododendron/genética
4.
Mol Phylogenet Evol ; 177: 107606, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-35952837

RESUMO

After the merger of the former Taxodiaceae and Cupressaceae s.s., currently the conifer family Cupressaceae (sensu lato) comprises seven subfamilies and 32 genera, most of which are important components of temperate and mountainous forests. With the exception of a recently published genus-level phylogeny of gymnosperms inferred from sequence analysis of 790 orthologs, previous phylogenetic studies of Cupressaceae were based mainly on morphological characters or a few molecular markers, and did not completely resolve the intergeneric relationships. In this study, we reconstructed a robust and well-resolved phylogeny of Cupressaceae represented by all 32 genera, using 1944 genes (Orthogroups) generated from transcriptome sequencing. Reticulate evolution analyses detected a possible ancient hybridization that occurred between ancestors of two subclades of Cupressoideae, including Microbiota-Platycladus-Tetraclinis (MPT) and Juniperus-Cupressus-Hesperocyparis-Callitropsis-Xanthocyparis (JCHCX), although both concatenation and coalescent trees are highly supported. Moreover, divergence time estimation and ancestral area reconstruction indicate that Cupressaceae very likely originated in Asia in the Triassic, and geographic isolation caused by continental separation drove the vicariant evolution of the two subfamilies Cupressoideae and Callitroideae in the northern and southern hemispheres, respectively. Evolutionary analyses of some morphological characters suggest that helically arranged linear-acicular leaves and imbricate bract-scale complexes represent ancestral states, and the shift from linear-acicular leaves to scale-like leaves was associated with the shift from helical to decussate arrangement. Our study sheds new light on phylogeny and evolutionary history of Cupressaceae, and strongly suggests that both dichotomous phylogenetic and reticulate evolution analyses be conducted in phylogenomic studies.


Assuntos
Cupressaceae , Juniperus , Cupressaceae/anatomia & histologia , Cupressaceae/genética , Cycadopsida , Hibridização Genética , Filogenia
5.
Int J Clin Pharmacol Ther ; 60(12): 499-508, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36197787

RESUMO

OBJECTIVES: Clinical pharmacists play a pivotal role in ensuring medication safety due to their detailed understanding of the medication-use process. This study aimed to propose the concept of pharmaceutical care pathway (PCP) in surgical care and design the work pattern and workflow in the healthcare systems of China. SETTING: Data were collected from patients in the Department of Hepatobiliary Surgery of the First People's Hospital of Lianyungang in China between January 2019 and December 2019. MATERIALS AND METHODS: The study was conducted using 346 patients in the control group and 363 in the intervention group. The control group was managed only by the clinical pathway (CP), while the intervention group was managed by the CP and PCP. MAIN OUTCOME MEASURE: Adverse drug reactions (ADRs), patient satisfaction, hospital expense, drug cost, length of stay, and prescription situations were documented. RESULTS: Using PCP, the rational use of drugs increased from 56% in the control group to 94.2% in the intervention group. Further, 124 (35.8%) ADRs in the control group and 44 (12.1%) ADRs in the intervention group were assessed using the Karch and -Lasagna scale. The mean hospital expense was 21,949.12 ± 2,311.25 yuan in the control group and 17,566.25 ± 1,082.56 yuan in the intervention group. The mean drug cost was 6,250.69 ± 589.35 yuan and 4,894.22 ± 356.14 yuan (1 US$ = 6.37 yuan). The mean length of stay was 12.23 ± 2.51 days and 8.35 ± 1.32 days in the control and intervention groups, respectively. Patient satisfaction increased significantly. CONCLUSION: PCP reduced the length of stay for patients and drug-related adverse events, increased the rational use of drugs, cost-effectiveness, patient satisfaction, and consequently, improved the quality of service in surgery medicine.


Assuntos
Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos , Assistência Farmacêutica , Humanos , Procedimentos Clínicos , Farmacêuticos , Análise Custo-Benefício
6.
Mol Ecol Resour ; 23(4): 844-854, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36479823

RESUMO

Genetic markers have emerged as one of the most promising tools for species identification and geographic traceability in biodiversity conservation and international trade of biological products. However, traditional molecular markers rarely have sufficient resolution at lower taxonomic levels, especially for discriminating closely related forest tree species and their populations. In this study, we developed a panel of RNA-Seq based single nucleotide polymorphism (SNP) markers for tracing the geographic origin of an endangered conifer, Cathaya argyrophylla, which is a paleoendemic restricted to four mountain regions in subtropical China. A total of 69 individuals from five populations (DLS, SHS, HP, BMS, and DYS) covering the entire range were used for transcriptome sequencing. Based on these transcriptomic data, we evaluated genetic variation and population structure of C. argyrophylla, and found extremely low nucleotide diversity but strong population differentiation. We also screened 113 population-specific SNP loci, including 96 for BMS, eight for DYS, six for SHS, two for HP, and one for one of the three subpopulations from DLS. According to these geographically diagnostic SNPs, we designed four population-specific molecular barcodes for PCR amplification. To test the utility and efficiency of the four markers in geographic discrimination, double-blind experiment was performed using 157 individuals labelled without any locality information. We found that almost all tested individuals could be successfully assigned to their geographic localities. Our study not only sheds some new light on the genetic profile of C. argyrophylla, but also provides a practical and cost-efficient solution for geographic traceability using transcriptome-derived SNPs.


Assuntos
Espécies em Perigo de Extinção , Transcriptoma , Animais , Humanos , Comércio , Internacionalidade , Polimorfismo de Nucleotídeo Único
7.
Cell Death Differ ; 30(10): 2280-2292, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37633968

RESUMO

Recent studies provide clues that astrocyte senescence is correlated with Parkinson's disease (PD) progression, while little is known about the molecular basis for astrocyte senescence in PD. Here, we found that cyclic GMP-AMP synthase (cGAS)/stimulator of interferon genes (STING) was upregulated in senescent astrocytes of PD and aged mice. Strikingly, deletion of astrocytic cGAS significantly prevented senescence of astrocytes and neurodegeneration. Furthermore, we identified LCN2 as the effector of cGAS-STING signal by RNA-Seq analysis. Genetic manipulation of LCN2 expression proved the regulation of cGAS-STING-LCN2 axis in astrocyte senescence. Additionally, YY1 was discovered as the transcription factor of LCN2 by chromatin immunoprecipitation. Binding of STING to YY1 impedes nuclear translocation of YY1. Herein, we determine the involvement of the cGAS-STING-YY1-LCN2 signaling cascade in the control of astrocyte senescence and PD progression. Together, this work fills the gap in our understanding of astrocyte senescence, and provides potential targets for delaying PD progression.

8.
Fitoterapia ; 136: 104183, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31150767

RESUMO

Diterpenoids are the main secondary metabolites of plants and with a range of biological activities. In the present study, 7 compounds were isolated from the hulls of rice (Oryza sativa L.). Among them, 3 diterpenoids are new namely, 3,20-epoxy-3α-hydroxy- 8,11,13-abietatrie-7-one (1), 4,6-epoxy-3ß-hydroxy-9ß-pimara-7,15-diene (2) and 2-((E)-3- (4-hydroxy-3-methoxyphenyl) allylidene) momilactone A (3). While, 4 terpenoids are known, namely momilactone A (4), momilactone B (5), ent-7-oxo-kaur-15-en-18-oic acid (6) and orizaterpenoid (7). The structures of these diterpenoids were elucidated using 1D and 2D NMR in combination with ESI-MS and HR-EI-MS. Furthermore, all isolated compounds displayed antifungal activities against four crop pathogenic fungi Magnaporthe grisea, Rhizoctonia solani, Blumeria graminearum and Fusarium oxysporum, and phytotoxicity against paddy weed Echinochloa crusgalli. The results suggested that rice could produce plenty of secondary metabolites to defense against weeds and pathogens.


Assuntos
Diterpenos/farmacologia , Fungicidas Industriais/farmacologia , Herbicidas/farmacologia , Oryza/química , Sementes/química , Diterpenos/isolamento & purificação , Echinochloa/efeitos dos fármacos , Fungicidas Industriais/isolamento & purificação , Herbicidas/isolamento & purificação , Estrutura Molecular , Compostos Fitoquímicos/isolamento & purificação , Compostos Fitoquímicos/farmacologia
9.
Rev Sci Instrum ; 87(11): 114502, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27910446

RESUMO

The high precision space electrostatic accelerometer is an instrument to measure the non-gravitational forces acting on a spacecraft. It is one of the key payloads for satellite gravity measurements and space fundamental physics experiments. The measurement error of the accelerometer directly affects the precision of gravity field recovery for the earth. This paper analyzes the sources of the bias according to the operating principle and structural constitution of the space electrostatic accelerometer. Models of bias due to the asymmetry of the displacement sensing system, including the mechanical sensor head and the capacitance sensing circuit, and the asymmetry of the feedback control actuator circuit are described separately. According to the two models, a method of bias self-calibration by using only the accelerometer data is proposed, based on the feedback voltage data of the accelerometer before and after modulating the DC biasing voltage (Vb) applied on its test mass. Two types of accelerometer biases are evaluated separately using in-orbit measurement data of a space electrostatic accelerometer. Based on the preliminary analysis, the bias of the accelerometer onboard of an experiment satellite is evaluated to be around 10-4 m/s2, about 4 orders of magnitude greater than the noise limit. Finally, considering the two asymmetries, a comprehensive bias model is analyzed. A modified method to directly calibrate the accelerometer comprehensive bias is proposed.

10.
Glia ; 44(1): 13-25, 2003 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-12951653

RESUMO

High-affinity excitatory amino acid transporters (EAATs) are essential to terminate glutamatergic neurotransmission and to prevent excitotoxicity. To date, five distinct EAATs have been cloned from animal and human tissues: GLAST (EAAT1), GLT-1 (EAAT2), EAAC1 (EAAT3), EAAT4, and EAAT5. EAAT1 and EAAT2 are commonly known as glial glutamate transporters, whereas EAAT3, EAAT4, and EAAT5 are neuronal. EAAT4 is largely expressed in cerebellar Purkinje cells. In this study, using immunohistochemistry and Western blotting, we found that EAAT4-like immunoreactivity (ir) is enriched in the spinal cord and forebrain. Double-labeled fluorescent immunostaining and confocal image analysis indicated that EAAT4-like ir colocalizes with an astrocytic marker, glial fibrillary acidic protein (GFAP). The astrocytic localization of EAAT4 was further confirmed in astrocyte cultures by double-labeled fluorescent immunocytochemistry and Western blotting. Reverse transcriptase-polymerase chain reaction analysis demonstrated mRNA expression of EAAT4 in astrocyte cultures. Sequencing confirmed the specificity of the amplified fragment. These results demonstrate that EAAT4 is expressed in astrocytes. This astrocytic localization of neuronal EAAT4 may reveal a new function of EAAT4 in the central nervous system.


Assuntos
Sistema X-AG de Transporte de Aminoácidos , Astrócitos/metabolismo , Ácido Glutâmico/metabolismo , Neurônios/metabolismo , Prosencéfalo/metabolismo , Receptores de Glutamato/metabolismo , Medula Espinal/metabolismo , Simportadores , Animais , Animais Recém-Nascidos , Especificidade de Anticorpos , Astrócitos/citologia , Células Cultivadas , Transportador 1 de Aminoácido Excitatório , Transportador 2 de Aminoácido Excitatório , Transportador 3 de Aminoácido Excitatório , Transportador 4 de Aminoácido Excitatório , Transportador 5 de Aminoácido Excitatório , Imunofluorescência , Proteína Glial Fibrilar Ácida/metabolismo , Proteínas de Transporte de Glutamato da Membrana Plasmática , Camundongos , Neurônios/citologia , Prosencéfalo/citologia , RNA Mensageiro/metabolismo , Receptores de Glutamato/genética , Medula Espinal/citologia
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