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1.
NPJ Parkinsons Dis ; 10(1): 5, 2024 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-38172178

RESUMO

REM sleep behavior disorder (RBD) symptoms in Parkinson's disease (PD) suggest both a clinically and pathologically malignant subtype. However, whether RBD symptoms are associated with alterations in the organization of whole-brain intrinsic functional networks in PD, especially at early disease stages, remains unclear. Here we use resting-state functional MRI, coupled with graph-theoretical approaches and network-based statistics analyses, and validated with large-scale network analyses, to characterize functional brain networks and their relationship with clinical measures in early PD patients with probable RBD (PD+pRBD), early PD patients without probable RBD (PD-pRBD) and healthy controls. Thirty-six PD+pRBD, 57 PD-pRBD and 71 healthy controls were included in the final analyses. The PD+pRBD group demonstrated decreased global efficiency (t = -2.036, P = 0.0432) compared to PD-pRBD, and decreased network efficiency, as well as comprehensively disrupted nodal efficiency and whole-brain networks (all eight networks, but especially in the sensorimotor, default mode and visual networks) compared to healthy controls. The PD-pRBD group showed decreased nodal degree in right ventral frontal cortex and more affected edges in the frontoparietal and ventral attention networks compared to healthy controls. Furthermore, the assortativity coefficient was negatively correlated with Montreal cognitive assessment scores in the PD+pRBD group (r = -0.365, P = 0.026, d = 0.154). The observation of altered whole-brain functional networks and its correlation with cognitive function in PD+pRBD suggest reorganization of the intrinsic functional connectivity to maintain the brain function in the early stage of the disease. Future longitudinal studies following these alterations along disease progression are warranted.

2.
BMC Biol ; 21(1): 239, 2023 10 31.
Artigo em Inglês | MEDLINE | ID: mdl-37904140

RESUMO

BACKGROUND: The Sino-Himalayan flora harbors highly diverse high-elevation biotas, but our understanding of its evolutionary history in temporal and spatial dimensions is limited. In this study, we integrated a dated phylogenetic tree with comprehensive species distribution data to investigate changes over time and space in floristic elements, including the tropical, Tethys, northern temperate, and East Asian floristic elements, across the entire Sino-Himalaya and its three floristic regions: the Yunnan Plateau, Hengduan Mountains, and East Himalaya regions. RESULTS: Our results revealed that the Sino-Himalayan flora developed from lowland biomes and was predominantly characterized by tropical floristic elements before the collision between the Indian subcontinent and Eurasia during the Early Cenozoic. Subsequently, from the Late Eocene onwards, the uplifts of the Himalaya and Hengduan Mountains transformed the Sino-Himalayan region into a wet and cold plateau, on which harsh and diverse ecological conditions forced the rapid evolution of local angiosperms, giving birth to characteristic taxa adapted to the high altitudes and cold habitat. The percentage of temperate floristic elements increased and exceeded that of tropical floristic elements by the Late Miocene. CONCLUSIONS: The Sino-Himalayan flora underwent four significant formation periods and experienced a considerable increase in endemic genera and species in the Miocene, which remain crucial to the present-day patterns of plant diversity. Our findings support the view that the Sino-Himalayan flora is relatively young but has ancient origins. The three major shifts in the divergence of genera and species during the four formation periods were primarily influenced by the uplifts of the Himalaya and Hengduan Mountains and the onset and intensification of the Asian monsoon system. Additionally, the temporal patterns of floristic elements differed among the three floristic regions of the Sino-Himalaya, indicating that the uplift of the Himalaya and surrounding areas was asynchronous. Compared to the Yunnan Plateau region, the East Himalaya and Hengduan Mountains experienced more recent and drastic uplifts, resulting in highly intricate topography with diverse habitats that promoted the rapid radiation of endemic genera and species in these regions.


Assuntos
Biodiversidade , Ecossistema , Gravidez , Humanos , Feminino , Filogenia , China , Plantas
3.
Org Lett ; 25(22): 4124-4129, 2023 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-37195070

RESUMO

A fully heterogeneous metallaphotocatalytic C-C cross-coupling of aryl/vinyl halides with alkyl/allyltrifluoroborates has been developed by employing integrated bipyridyl-Ni(II)-carbon nitride as a stable and recyclable bifunctional catalyst. This visible-light-mediated heterogeneous protocol allows for the sustainable synthesis of diverse valuable diarylmethanes and allylarenes in high efficiency.


Assuntos
2,2'-Dipiridil , Compostos de Vinila , Estrutura Molecular , Catálise
4.
J Am Chem Soc ; 144(43): 20126-20133, 2022 11 02.
Artigo em Inglês | MEDLINE | ID: mdl-36259686

RESUMO

We report herein the in situ electrochemical scanning tunneling microscopy (ECSTM) study on the synergistic effect of Mg2+ in CO2 reduction reaction (CO2RR) catalyzed by cobalt phthalocyanine (CoPc). ECSTM measurement molecularly resolves the self-assembled CoPc monolayer on the Au(111) substrate. In the CO2 environment, high-contrast species are observed in the adlayer and assigned to the CO2 adsorption on CoPc. Furthermore, the contrast of the CO2-bound complex is higher in Mg2+-containing electrolytes than in Mg2+-free electrolytes, indicating the formation of the CoPc-CO2-Mg2+ complex. The surface coverage of adsorbed CO2 is positively correlated with the Mg2+ concentration as the additive in electrolytes up to a plateau of 30.8 ± 2.7% when c(Mg2+) > 30 mM. The potential step experiment indicates the higher CO2 adsorption dynamics in Mg2+-containing electrolytes than without Mg2+. The rate constants of CO2 adsorption and dissociation in different electrolytes are extracted from the data fitting of statistical results from in situ ECSTM experiments.


Assuntos
Microscopia de Tunelamento , Compostos Organometálicos , Microscopia de Tunelamento/métodos , Dióxido de Carbono , Ouro
5.
Cladistics ; 37(6): 803-815, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34841588

RESUMO

Biodiversity exchanges across the Malesian region, linking the distinct biotas of Asia and Australia, have long attracted the curiosity of biologists. Tetrastigma (Vitaceae) has a wide distribution in Asia through the Sunda archipelago to Australia and provides a good case to elucidate floristic exchange between Asia and Australia. Tetrastigma species have fleshy fruits that are consumed by birds, representing a lineage with a predictable dispersal across island chains. We herein estimate the divergence times and reconstruct the biogeographic history of Tetrastigma with intensive taxon sampling (96 of approximately 120 species; >80%) using 10 chloroplast loci. The biogeographic history of Tetrastigma was reconstructed with 4-area and 6-area divisions by delineating the Sunda region into one or three areas of endemism based on a phylogenetic bioregionalization analysis and the geological history of Malesia. The 4-area division shows that Tetrastigma originated in continental Asia and diverged from the recently segregated genus Pseudocayratia in the early Eocene (49.43 Ma). Dispersal from continental Asia might have started in the late Eocene but mainly occurred in the last 10 Myr. Continental Asia is indicated to be the most important source area while Sunda is the biggest sink, with 16 of the 27 dispersal events inferred from continental Asia to Sunda. Only seven dispersal events are inferred arriving in the Sahul plate and one reverse dispersal from Sahul back to Asia. The 6-area division suggests that the Philippines have been an active junction between Asia and Australia. The biogeographic history of Tetrastigma illustrates an asymmetric floristic exchange between Asia and Australia in this genus, which has been facilitated by the formation of terrestrial connections in the late Miocene and the expansion of wet tropical forests across Wallace's Line and beyond.


Assuntos
Vitaceae , Ásia , Austrália , Cloroplastos/genética , DNA de Cloroplastos , Filogeografia , Dispersão Vegetal , Vitaceae/classificação , Vitaceae/genética
6.
Psych J ; 10(4): 668-669, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34034361

RESUMO

In this study, we examined the relationships among proactive vitality management (PVM), work engagement, and mental health. A total of 392 call center employees completed the survey. The results of structural equation modeling analyses supported that work engagement meditated the positive relationship between PVM and mental health.


Assuntos
Saúde Mental , Engajamento no Trabalho , Humanos , Inquéritos e Questionários
7.
Parkinsonism Relat Disord ; 68: 85-90, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31689588

RESUMO

INTRODUCTION: Freezing of gait (FOG) contributes to falls in Parkinson's disease (PD), but robust, effective treatments remain elusive. There is evidence indicating that the supplementary motor area (SMA) plays an important role in the pathogenesis of FOG and may therefore be a potential neuromodulation target. The present study explored the clinical efficacy of high-frequency repetitive transcranial magnetic stimulation (rTMS) over the SMA on FOG in PD patients. METHODS: A group of 30 PD patients with FOG were enrolled in a randomized, double-blind, sham-controlled trial. Patients were randomly allocated 2:1 to receive ten sessions of either real (N = 20) or sham (N = 10) 10 Hz rTMS over SMA. The patients were assessed at baseline (T0), after the 5th (T1) and 10th (T2) sessions, and then 2 weeks (T3) and 4 weeks (T4) after the last session. The primary clinical outcome was the Freezing of Gait Questionnaire score (FOGQ), with the Movement Disorder Society-Unified Parkinson's Disease Rating Scale motor scores (MDS-UPDRS III) and Timed Up and Go test as secondary clinical outcomes. All the assessments were carried out at the "ON" state. RESULTS: With a four week's follow-up, there were significant interaction effects in the FOGQ (effect of group*time, p = 0.04), MDS-UPDRS III (p = 0.02) and several gait variables (total duration, p < 0.01; cadence, p = 0.04; turn duration, p = 0.01; and turn to sit duration, p = 0.02). Post-hoc analyses revealed a significantly decreased FOGQ score at T2 and T4, and significant improvements of MDS-UPDRS III and gait variables at T1, T2, T3 and T4 in the rTMS group. No significant improvements were found in the sham group. CONCLUSION: High-frequency rTMS over SMA may ultimately serve as an add-on therapy for alleviating FOG in PD patients.


Assuntos
Transtornos Neurológicos da Marcha/terapia , Córtex Motor , Avaliação de Resultados em Cuidados de Saúde , Doença de Parkinson/terapia , Estimulação Magnética Transcraniana/métodos , Idoso , Método Duplo-Cego , Feminino , Seguimentos , Transtornos Neurológicos da Marcha/etiologia , Humanos , Masculino , Pessoa de Meia-Idade , Doença de Parkinson/complicações , Placebos
8.
Acta Biochim Biophys Sin (Shanghai) ; 50(3): 263-272, 2018 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-29514220

RESUMO

Melanoma is the most malignant and aggressive form of skin carcinoma originating in the pigment-producing melanocytes. In this study, to further investigate the molecular mechanisms of the development and progression of melanoma, we explored the impacts of long non-coding RNA (lncRNA) CASC2 on melanoma cell functions. Microarray analysis was carried out to identify the expression of lncRNA CASC2 in melanoma cells. MiR-181a was predicted as a sponging target of CASC2 by miRcode, while the 3'-UTR of Plexin C1 (PLXNC1) was a potential target of miR-181a according to the TargetScan database. The correlation among CASC2, miR-181a, and PLXNC1 was verified by dual luciferase reporter assay and qRT-PCR. After manipulation of CASC2, miR-181a and PLXNC1 expression with transfection in A375 and M14 cells, cell viability, apoptosis, and invasive ability were evaluated using CCK-8, flow cytometry and Transwell assays, respectively. A low expression of CASC2 was detected in melanoma tissues and cells. Dual luciferase reporting assay confirmed that miR-181a targeted the 3'-UTR of PLXNC1. Furthermore, CASC2 could efficiently sponge miR-181a, thereby facilitating the expression of PLXNC1. Up-regulation of CASC2 suppressed the cell proliferation and invasion, but induced the apoptosis of melanoma cells. Our results demonstrated that lncRNA CASC2 can promote PLXNC1 expression by sponging miR-181a, thereby inhibiting the proliferation and invasion of melanoma cells, indicating that lncRNA CASC2 functions via the miR-181a/PLXNC1 axis in melanoma.


Assuntos
Carcinogênese/genética , Melanoma/genética , MicroRNAs/genética , RNA Longo não Codificante/genética , Receptores Virais/genética , Regiões 3' não Traduzidas/genética , Apoptose/genética , Carcinogênese/metabolismo , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células/genética , Regulação Neoplásica da Expressão Gênica , Células HEK293 , Humanos , Melanoma/metabolismo , Melanoma/patologia , Receptores Virais/metabolismo , Proteínas Supressoras de Tumor/genética
9.
Nature ; 554(7691): 234-238, 2018 02 08.
Artigo em Inglês | MEDLINE | ID: mdl-29420476

RESUMO

High species diversity may result from recent rapid speciation in a 'cradle' and/or the gradual accumulation and preservation of species over time in a 'museum'. China harbours nearly 10% of angiosperm species worldwide and has long been considered as both a museum, owing to the presence of many species with hypothesized ancient origins, and a cradle, as many lineages have originated as recent topographic changes and climatic shifts-such as the formation of the Qinghai-Tibetan Plateau and the development of the monsoon-provided new habitats that promoted remarkable radiation. However, no detailed phylogenetic study has addressed when and how the major components of the Chinese angiosperm flora assembled to form the present-day vegetation. Here we investigate the spatio-temporal divergence patterns of the Chinese flora using a dated phylogeny of 92% of the angiosperm genera for the region, a nearly complete species-level tree comprising 26,978 species and detailed spatial distribution data. We found that 66% of the angiosperm genera in China did not originate until early in the Miocene epoch (23 million years ago (Mya)). The flora of eastern China bears a signature of older divergence (mean divergence times of 22.04-25.39 Mya), phylogenetic overdispersion (spatial co-occurrence of distant relatives) and higher phylogenetic diversity. In western China, the flora shows more recent divergence (mean divergence times of 15.29-18.86 Mya), pronounced phylogenetic clustering (co-occurrence of close relatives) and lower phylogenetic diversity. Analyses of species-level phylogenetic diversity using simulated branch lengths yielded results similar to genus-level patterns. Our analyses indicate that eastern China represents a floristic museum, and western China an evolutionary cradle, for herbaceous genera; eastern China has served as both a museum and a cradle for woody genera. These results identify areas of high species richness and phylogenetic diversity, and provide a foundation on which to build conservation efforts in China.


Assuntos
Biodiversidade , Magnoliopsida/classificação , Filogenia , China , Conservação dos Recursos Naturais/métodos , Evolução Molecular , Mapeamento Geográfico , Análise de Regressão , Análise Espaço-Temporal
10.
Neurosci Bull ; 32(6): 572-576, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27699718

RESUMO

Olfactory dysfunction has been reported in Parkinson's disease (PD) patients carrying the LRRK2 G2019S variant in Caucasians but rarely in those with the LRRK2 G2385R variant. In this study, we performed genotyping for the LRRK2 G2385R variant in PD patients recruited from the Movement Disorder Clinic of Xuanwu Hospital in Beijing and in healthy controls randomly selected from the Beijing Longitudinal Study on Aging cohort. The "five-odor olfactory detection array", an olfactory threshold test, was used to assess olfactory function. One hundred and eighty-six participants were enrolled, comprising 43 PD patients without (iPD) and 25 with (LRRK2-PD) the LRRK2 G2385R variant, and 118 healthy controls. Our results showed that the threshold of olfactory identification was significantly worse in PD patients than in controls, but not significantly different between the iPD and LRRK2-PD groups. These findings suggested that although olfactory function in LRRK2-PD patients is impaired, it is similar to that in iPD patients.


Assuntos
Serina-Treonina Proteína Quinase-2 com Repetições Ricas em Leucina/genética , Transtornos do Olfato/etiologia , Doença de Parkinson/complicações , Doença de Parkinson/genética , Polimorfismo de Nucleotídeo Único/genética , Idoso , Idoso de 80 Anos ou mais , Arginina/genética , Feminino , Predisposição Genética para Doença , Genótipo , Glicina/genética , Humanos , Masculino , Pessoa de Meia-Idade , Limiar Sensorial/fisiologia
11.
Nat Prod Res ; 30(10): 1144-9, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26140390

RESUMO

A new monoterpenoid indole alkaloid compound (1) and six known monoterpenoid indole alkaloids compounds (2-7) were isolated from the barks of Voacanga africana Staph. The structures were established by spectral analysis as ibogamine-16-carboxylic acid,17,20-didehydro-5,6-dioxo-10-methoxy-methyl ester (1), voacamine (2), vobasine (3), voacangine (4), voacristine (5), 19-epi-voacristine (6) and 19-epi-heyneanine (7). Compound 1 was confirmed by X-ray crystallographic analysis. All of the isolated compounds were evaluated for cytotoxicity against five cell lines (HEPG-2, A375, MDA-MB-231, SH-SY5Y, CT26). Among them, compounds 2 and 6 displayed significant inhibitory activities, compounds 3, 4 and 5 showed moderate inhibitory activities, while compounds 1 and 7 showed no inhibitory activities against the five cell lines.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Alcaloides de Triptamina e Secologanina/isolamento & purificação , Alcaloides de Triptamina e Secologanina/farmacologia , Voacanga/química , Antineoplásicos Fitogênicos/isolamento & purificação , Hidrocarbonetos Aromáticos com Pontes/isolamento & purificação , Hidrocarbonetos Aromáticos com Pontes/farmacologia , Linhagem Celular Tumoral/efeitos dos fármacos , Humanos , Ibogaína/análogos & derivados , Ibogaína/isolamento & purificação , Alcaloides Indólicos/isolamento & purificação , Estrutura Molecular , Casca de Planta/química
13.
Zhejiang Da Xue Xue Bao Yi Xue Ban ; 39(4): 357-63, 2010 07.
Artigo em Chinês | MEDLINE | ID: mdl-20731033

RESUMO

OBJECTIVE: To investigate the interaction between myeloid-derived suppressor cells (MDSCs) and nature killer cells during acute fulminate hepatitis. METHODS: Acute fulminate hepatitis were induced by i.p. co-injection of LPS and D-GalN in mice, and the ratio of MDSCs,NK cells and the activation of NK cells in different tissues were analyzed by FACS at 0 h,1.5 h,3 h and 6 h. RESULTS: The percentage of MDSCs and NKG2D+NK cells in different tissues increased as acute fulminate hepatitis progressed, with the increased NK cells in liver tissue. The mean fluorescence intensity of NKG2D on NK cells in different tissues were also enhanced. CONCLUSION: MDSCs induce the proliferation and activation of NK cells in mice with acute fulminate hepatitis.


Assuntos
Hepatite/imunologia , Células Matadoras Naturais/imunologia , Falência Hepática Aguda/imunologia , Células Mieloides/imunologia , Linfócitos T Reguladores/imunologia , Doença Aguda , Animais , Linfócitos T CD8-Positivos/imunologia , Feminino , Hepatite/etiologia , Lipopolissacarídeos , Falência Hepática Aguda/induzido quimicamente , Masculino , Camundongos , Camundongos Endogâmicos C57BL
14.
J Integr Plant Biol ; 51(11): 1040-9, 2009 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19903225

RESUMO

Substrate selectivity of glycerol-3-phosphate acyltransferase (EC 2. 3. 1. 15) of rice (Oryza sativa L.) was explored in a comparative study of acyltransferases from seven plant species. In vitro labeling of acyl carrier protein (ACP) with (14)C or (3)H showed that acyltransferase from chill-sensitive plants, such as rice that uses either oleic (18:1) or palmitic acid (16:0) as acyl donor at comparable rates, displays lower selectivity than the enzyme from chill-resistant plants, such as spinach, which preferentially uses oleic acid (18:1) rather than palmitic acid (16:0) as an acyl donor. This may be a result of the size and character of the substrate-binding pocket of acyltransferase. Homology modeling and protein structure-based sequence alignment of acyltransferases revealed that proteins from either chill-sensitive or chill-tolerant plants shared a highly conserved domain containing the proposed substrate-binding pocket. However, the aligned residues surrounding the substrate-binding pocket are highly heterogeneous and may have an influence mainly on the size of the substrate binding pockets of acyltransferases. The substrate selectivity of acyltransferase of rice can be improved by enlarging the substrate-binding pocket using molecular biological methods.


Assuntos
Glicerol-3-Fosfato O-Aciltransferase/metabolismo , Oryza/enzimologia , Sequência de Aminoácidos , Sítios de Ligação , Biocatálise , Sequência Conservada , Evolução Molecular , Glicerol-3-Fosfato O-Aciltransferase/química , Lisofosfolipídeos/metabolismo , Dados de Sequência Molecular , Estrutura Secundária de Proteína , Padrões de Referência , Alinhamento de Sequência , Especificidade por Substrato
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