Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 16 de 16
Filtrar
1.
Zhongguo Zhong Yao Za Zhi ; 48(6): 1664-1672, 2023 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-37005854

RESUMO

In this study, the Web of Science and China National Knowledge Infrastructure(CNKI) were searched comprehensively for the literature about the research on Polygalae Radix. After manual screening, 1 207 Chinese articles and 263 English articles were included in this study. Excel was used to draw the line chart of the annual number of relevant publications. CiteSpace 6.1.R3 was used for the visual analysis of author cooperation, publishing institutions, keyword co-occurrence, keyword clustering, and bursts in the research on Polygalae Radix. The results showed that the number of articles published in Chinese and English increased linearly, which indicated the rising research popularity of Polygalae Radix. WANG J and LIU X were the authors publishing the most articles in Chinese and English, respectively. Shanxi University of Chinese Medicine and Chinese Academy of Medical Sciences were the research institutions with the largest number of Chinese and English publications in this field, respectively. The institutions publishing the relevant articles in English formed a system with the Chinese Academy of Medical Sciences as the core. According to the keywords, the research hotspots of Polygalae Radix included variety selection and breeding, quality standard, extraction and identification of active chemical components, prescription compatibility, processing, clinical medication rules, and pharmacological mechanism. The research frontiers were the molecular mechanisms of Polygalae Radix and its active components in exerting the protective effect on brain nerve, regulating receptor pathways, alleviating anxiety and Alzheimer's disease, as well as data mining and clinical medication summary. This study has reference significance for the topic selection and frontier identification of the future research on Polygalae Radix.


Assuntos
Melhoramento Vegetal , Raízes de Plantas , China , Raízes de Plantas/química , Encéfalo , Publicações
2.
Dalton Trans ; 50(19): 6725-6734, 2021 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-33912883

RESUMO

van der Waals heterojunctions formed by transition metal dichalcogenides (TMDs) and fullerenes are promising candidates for novel photovoltaic devices due to the excellent optoelectronic properties of both TMDs and fullerenes. However, relevant experimental and theoretical investigations remain scarce to the best of our knowledge. Herein, we have first employed static density functional theory (DFT) calculations in combination with time-domain density functional theory (TDDFT) based nonadiabatic dynamics simulations to rationally evaluate the photovoltaic performances of four TMD@fullerene heterostructures, i.e. WSe2@C60, WSe2@C70, MoTe2@C60 and MoTe2@C70, respectively. Our simulation results indicate that the C70-based heterostructures overall have better photoinduced electron transfer efficiencies than their C60-based counterparts, among which the performance of the WSe2@C70 heterostructure is the best and the electron transfer from WSe2 to C70 almost accomplishes within 1 ps. In addition, the large build-in potential of about 0.75 eV of WSe2@C70 is beneficial for the charge separation processes. Our present work not only selects the van der Waals TMD@fullerene heterojunctions that might have excellent photovoltaic properties, but also paves the way for the rational design of novel heterojunctions with better optoelectronic performances with DFT and TDDFT simulations in the future.

3.
Int J Mol Sci ; 21(24)2020 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-33322211

RESUMO

The KT/HAK/KUP (HAK) family is the largest potassium (K+) transporter family in plants, which plays key roles in K+ uptake and homeostasis, stress resistance, and root and embryo development. However, the HAK family has not yet been characterized in Brassica napus. In this study, 40 putative B. napus HAK genes (BnaHAKs) are identified and divided into four groups (Groups I-III and V) on the basis of phylogenetic analysis. Gene structure analysis revealed 10 conserved intron insertion sites across different groups. Collinearity analysis demonstrated that both allopolyploidization and small-scale duplication events contributed to the large expansion of BnaHAKs. Transcription factor (TF)-binding network construction, cis-element analysis, and microRNA prediction revealed that the expression of BnaHAKs is regulated by multiple factors. Analysis of RNA-sequencing data further revealed extensive expression profiles of the BnaHAKs in groups II, III, and V, with limited expression in group I. Compared with group I, most of the BnaHAKs in groups II, III, and V were more upregulated by hormone induction based on RNA-sequencing data. Reverse transcription-quantitative polymerase reaction analysis revealed that the expression of eight BnaHAKs of groups I and V was markedly upregulated under K+-deficiency treatment. Collectively, our results provide valuable information and key candidate genes for further functional studies of BnaHAKs.


Assuntos
Brassica napus/metabolismo , Proteínas de Transporte de Cátions/genética , Proteínas de Transporte de Cátions/metabolismo , Proteínas de Plantas/metabolismo , Deficiência de Potássio/genética , Potássio/metabolismo , Brassica napus/genética , Duplicação Gênica , Regulação da Expressão Gênica de Plantas/genética , Genoma de Planta , Íntrons , Família Multigênica , Filogenia , Proteínas de Plantas/genética , Regiões Promotoras Genéticas , RNA-Seq , Reação em Cadeia da Polimerase Via Transcriptase Reversa
4.
Spinal Cord ; 58(12): 1310-1316, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32561846

RESUMO

STUDY DESIGN: Retrospective analysis. SETTING: China Rehabilitation Research Center, Beijing, China. OBJECTIVE: To explore possible mechanisms underlying spinal cord injury (SCI) in children caused by hyperextension of the spine while dancing. METHODS: The clinical records of 88 children with SCI (mean age, 5.97 years; age range, 4-10 years) admitted to our hospital from January 1989 to October 2019 were retrospectively reviewed. Computed tomography and magnetic resonance imaging were performed on the day of injury. The time from injury to development of paralysis, as well as post-injury activities were surveyed, while abnormal patterns on images, the range of the involved vertebrae, and the extents of edema and atrophy were assessed. RESULTS: Among the 88 patients, 6 (6.8%) were unable to move immediately after SCI, while paralysis occurred in 42, 23, and 17 patients at <30, 30-60, and >60 min after SCI, respectively. The neurological level of injury of 84 patients was between T4 and T12. On sagittal T2-weighted images (T2WIs), the longitudinal range of spinal cord edema was more than one vertebral body in 65 patients, while spinal cord atrophy below T8 was found in 40 patients. On axial T2WIs, although three patients had none, long T2 signals were found in the central gray matter of seven patients. Meanwhile, necrosis of the central area combined with the peripheral white matter was observed in 57 patients, while three patients had total involvement on a cross section. CONCLUSION: Ischemia-related damage, rather than direct trauma to the spinal cord, may play an important role in SCI due to spinal hyperextension during dancing.


Assuntos
Dança , Traumatismos da Medula Espinal , Vértebras Cervicais , Criança , Pré-Escolar , Humanos , Isquemia , Imageamento por Ressonância Magnética , Estudos Retrospectivos , Medula Espinal , Traumatismos da Medula Espinal/complicações , Traumatismos da Medula Espinal/diagnóstico por imagem , Traumatismos da Medula Espinal/epidemiologia
5.
Int J Mol Sci ; 21(5)2020 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-32143436

RESUMO

Phosphate (Pi) transporters play critical roles in Pi acquisition and homeostasis. However, currently little is known about these genes in oil crops. In this study, we aimed to characterize the five Pi transporter gene families (PHT1-5) in allotetraploid Brassica napus. We identified and characterized 81 putative PHT genes in B. napus (BnaPHTs), including 45 genes in PHT1 family (BnaPHT1s), four BnaPHT2s, 10 BnaPHT3s, 13 BnaPHT4s and nine BnaPHT5s. Phylogenetic analyses showed that the largest PHT1 family could be divided into two groups (Group I and II), while PHT4 may be classified into five, Groups I-V. Gene structure analysis revealed that the exon-intron pattern was conservative within the same family or group. The sequence characteristics of these five families were quite different, which may contribute to their functional divergence. Transcription factor (TF) binding network analyses identified many potential TF binding sites in the promoter regions of candidates, implying their possible regulating patterns. Collinearity analysis demonstrated that most BnaPHTs were derived from an allopolyploidization event (~40.7%) between Brassica rapa and Brassica oleracea ancestors, and small-scale segmental duplication events (~39.5%) in the descendant. RNA-Seq analyses proved that many BnaPHTs were preferentially expressed in leaf and flower tissues. The expression profiles of most colinearity-pairs in B. napus are highly correlated, implying functional redundancy, while a few pairs may have undergone neo-functionalization or sub-functionalization during evolution. The expression levels of many BnaPHTs tend to be up-regulated by different hormones inductions, especially for IAA, ABA and 6-BA treatments. qRT-PCR assay demonstrated that six BnaPHT1s (BnaPHT1.11, BnaPHT1.14, BnaPHT1.20, BnaPHT1.35, BnaPHT1.41, BnaPHT1.44) were significantly up-regulated under low- and/or rich- Pi conditions in B. napus roots. This work analyzes the evolution and expression of the PHT family in Brassica napus, which will help further research on their role in Pi transport.


Assuntos
Brassica napus/genética , Proteínas de Transporte de Fosfato/genética , Fósforo/química , Proteínas de Plantas/genética , Sítios de Ligação , Transporte Biológico , Mapeamento Cromossômico , Cromossomos de Plantas , Biologia Computacional , Evolução Molecular , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Genes de Plantas , Homeostase , Filogenia , Raízes de Plantas/metabolismo , Ligação Proteica , Fatores de Transcrição/genética
6.
BMC Plant Biol ; 20(1): 115, 2020 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-32171243

RESUMO

BACKGROUND: The basic helix-loop-helix (bHLH) gene family is one of the largest transcription factor families in plants and is functionally characterized in diverse species. However, less is known about its functions in the economically important allopolyploid oil crop, Brassica napus. RESULTS: We identified 602 potential bHLHs in the B. napus genome (BnabHLHs) and categorized them into 35 subfamilies, including seven newly separated subfamilies, based on phylogeny, protein structure, and exon-intron organization analysis. The intron insertion patterns of this gene family were analyzed and a total of eight types were identified in the bHLH regions of BnabHLHs. Chromosome distribution and synteny analyses revealed that hybridization between Brassica rapa and Brassica oleracea was the main expansion mechanism for BnabHLHs. Expression analyses showed that BnabHLHs were widely in different plant tissues and formed seven main patterns, suggesting they may participate in various aspects of B. napus development. Furthermore, when roots were treated with five different hormones (IAA, auxin; GA3, gibberellin; 6-BA, cytokinin; ABA, abscisic acid and ACC, ethylene), the expression profiles of BnabHLHs changed significantly, with many showing increased expression. The induction of five candidate BnabHLHs was confirmed following the five hormone treatments via qRT-PCR. Up to 246 BnabHLHs from nine subfamilies were predicted to have potential roles relating to root development through the joint analysis of their expression profiles and homolog function. CONCLUSION: The 602 BnabHLHs identified from B. napus were classified into 35 subfamilies, and those members from the same subfamily generally had similar sequence motifs. Overall, we found that BnabHLHs may be widely involved in root development in B. napus. Moreover, this study provides important insights into the potential functions of the BnabHLHs super gene family and thus will be useful in future gene function research.


Assuntos
Brassica napus/genética , Família Multigênica , Proteínas de Plantas/genética , Fatores de Transcrição/genética , Transcriptoma , Brassica napus/metabolismo , Proteínas de Plantas/metabolismo , Fatores de Transcrição/metabolismo
7.
ACS Appl Mater Interfaces ; 11(50): 46783-46791, 2019 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-31769644

RESUMO

Solid polymer electrolytes can be used to construct solid-state lithium batteries (SSLBs) using lithium metals as the anode. However, the lifespan and safety problems of SSLBs caused by lithium dendrite growth have hindered their practical application. Here, we have designed and prepared a rigid-flexible asymmetric solid electrolyte (ASE) that is used in building SSLBs. The ASE can inhibit efficiently the growth of lithium dendrites and lead to a long cycle life of SSLBs due to the hierarchical structure of a combination of "polymer-in-ceramic" (i.e., rigid ceramic layer of Li6.4La3Zr1.4Ta0.6O12) and "LiBOB-in-polymer" (i.e., soft polymer-layer of polyethylene oxide and LiBOB components). The results demonstrated that a symmetrical battery with ASE (Li|ASE|Li) can be steadily cycled for more than 2000 h and yielded a flat plating/stripping voltage profile under a current density of 0.1 mA cm-2. As a consequence, the SSLB of LiFePO4|ASE|Li delivered a specific capacity of 155.1 mA h g-1 with a capacity retention rate up to 90.2% after 200 cycles with the Coulombic efficiency over 99.6% per cycle. This asymmetric structure combines the advantages of ceramics and polymers, providing an ingenious solution for building rigid and flexible solid electrolytes.

8.
RSC Adv ; 8(41): 23397-23403, 2018 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-35540114

RESUMO

The mechanism of Li-O2 batteries is based on the reactions of lithium ions and oxygen, which hold a theoretical higher energy density of approximately 3500 W h kg-1. In order to improve the practical specific capacity and cycling performance of Li-O2 batteries, a catalytically active mechanically robust air cathode is required. In this work, we synthesized a freestanding catalytic cathode with RuO2 decorated 3D web Co3O4 nanowires on nickel foam. When the specific capacity was limited at 500 mA h g-1, the RuO2-Co3O4/NiF had a stable cycling life of up to 122 times. The outstanding performance can be primarily attributed to the robust freestanding Co3O4 nanowires with RuO2 loading. The unique 3D web nanowire structure provides a large surface for Li2O2 growth and RuO2 nanoparticle loading, and the RuO2 nanoparticles help to promote the round trip deposition and decomposition of Li2O2, therefore enhancing the cycling behavior. This result indicates the superiority of RuO2-Co3O4/NiF as a freestanding highly efficient catalytic cathode for Li-O2 batteries.

9.
ChemSusChem ; 9(11): 1339-47, 2016 06 08.
Artigo em Inglês | MEDLINE | ID: mdl-27144965

RESUMO

Iron-based heterogeneous catalysts, which were generally prepared by pyrolysis of iron complexes on supports at elevated temperature, were found to be capable of catalyzing the transfer hydrogenation of furfural (FF) to furfuryl alcohol (FFA). The effects of metal precursor, nitrogen precursor, pyrolysis temperature, and support on catalytic performance were examined thoroughly, and a comprehensive study of the reaction parameters was also performed. The highest selectivity of FFA reached 83.0 % with a FF conversion of 91.6 % under the optimal reaction condition. Catalyst characterization suggested that iron cations coordinated by pyridinic nitrogen functionalities were responsible for the enhanced catalytic activity. The iron catalyst could be recycled without significant loss of catalytic activity for five runs, and the destruction of the nitrogen-iron species, the presence of crystallized Fe2 O3 phase, and the pore structure change were the main reasons for catalyst deactivation.


Assuntos
Carbono/química , Furaldeído/química , Furanos/química , Ferro/química , Nitrogênio/química , Catálise , Hidrogênio/química , Hidrogenação , Temperatura
10.
J Spinal Cord Med ; 39(1): 15-23, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26496045

RESUMO

CONTEXT: Surface electromyography (SEMG) may be a sensitive marker for distinguishing the activity of trunk muscles, which are critical to functional mobility recovery in patients with spinal cord injury (SCI). OBJECTIVES: This manuscript presents a systematic review and meta-analysis of the published literature on the effect of SEMG as a measure of trunk muscle activity in patients with SCI. METHODS: A comprehensive search of the research literature included Pubmed, Medline, CNKI, WANFANG DATA, Web of Science, Elsevier, Wiley-Blackwell, Karger, OVID, and a review of reference lists within found articles. Case-control, cohort, and cross-sectional studies were included in the review. RESULTS: Eleven studies were included in this meta-analysis. Trunk muscle activities for the sitting condition were greater in patients with SCI than normal subjects. SEMG activity of trunk muscles for the sitting condition and posterior transfer was greater in patients with high level (HL)-SCI compared to those with low level (LL)-SCI. In addition, across studies, the level of trunk muscle activity for various difficulty settings was different for a given SCI group. CONCLUSION: This systematic review evaluated the value of trunk muscles for patients with SCI. We recommend use of SEMG as an assessment tool for improving the comparability and interpretability of trunk muscle activity of SCI therapeutic strategies.


Assuntos
Eletromiografia/métodos , Músculo Esquelético/fisiologia , Traumatismos da Medula Espinal/diagnóstico , Estudos de Casos e Controles , Humanos , Músculo Esquelético/inervação , Tronco/fisiologia
13.
Nan Fang Yi Ke Da Xue Xue Bao ; 28(2): 193-5, 2008 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-18250040

RESUMO

OBJECTIVE: To establish an effective method for isolating and culturing outer root sheath (ORS) bulge cells, dermal sheath cells (DSCs) and dermal papilla cells (DPCs) derived from human hair follicle. METHODS: Small scalp specimens were incubated in the presence of dispase at 37 degrees celsius; for 2 h, the hair shafts with ORS embedded in the dermal sheath (DS) were extracted under dissecting microscope, and the ORS tissue were inoculated onto Petri dish. The specimens were transected at the interface between the dermis and subcutaneous tissue. The portions of DS and DP (linked with and enclosed by DS) embedded in the adipose tissue were pulled out and incubated with collagenase at 37 degrees celsius; for 6-8 h, and the DP and DSCs were isolated by repeated low-speed centrifugation and cultured respectively on Petri dishes. The cultured ORS bulge cells were identified by immunohistochemistry with K19 antibody and DPCs and DSCs by immunohistochemistry with alpha-actin antibody. RESULTS: Purified ORS bulge cells, DSCs and DPCs could be harvested from the same human hair follicle. CONCLUSION: This new method allows efficient, rapid, and simultaneous isolation and culture of ORS bulge cells, DSCs and DPCs.


Assuntos
Técnicas de Cultura de Células/métodos , Folículo Piloso/citologia , Separação Celular , Células Cultivadas , Derme/citologia , Humanos , Imuno-Histoquímica , Couro Cabeludo/citologia
14.
Nan Fang Yi Ke Da Xue Xue Bao ; 27(9): 1365-7, 2007 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-17884780

RESUMO

OBJECTIVE: To observe the hair follicle regeneration after subcutaneous implantation of hair follicle cell mixture in nude mice. METHODS: The hair papilla cells, dermal sheath cells, outer root sheath and fibroblasts of human scalp were mixed with the hair follicle epithelial cells and implanted subcutaneously in nude mice to observe the regeneration of the hair follicle. RESULTS AND CONCLUSION: Formation of intact hair follicle-like structures was observed in the skin sections of the recipient nude mice, suggesting the feasibility of this approach for hair follicle regeneration in vivo.


Assuntos
Transplante de Células , Folículo Piloso/citologia , Folículo Piloso/fisiologia , Regeneração , Animais , Folículo Piloso/metabolismo , Folículo Piloso/transplante , Humanos , Injeções Subcutâneas , Camundongos , Camundongos Nus , Pigmentação da Pele , Fatores de Tempo
15.
Genomics Proteomics Bioinformatics ; 3(2): 94-106, 2005 May.
Artigo em Inglês | MEDLINE | ID: mdl-16393146

RESUMO

Domain insertions and deletions lead to variations in the domain architectures of the proteins from their common ancestor. In this work, we investigated four groups of the RhoGEF-containing proteins from different organisms with domain architectures RhoGEF-PH-SH3, SH3-RhoGEF-PH, RhoGEF-PH, and SH3-RhoGEF defined in the Pfam database. The phylogenetic trees were constructed using each individual domain and/or the combinations of all the domains. The phylogenetic analysis suggests that RhoGEF-PH-SH3 and SH3-RhoGEF-PH might have evolved from RhoGEF-PH through the insertion of SH3 independently, while SH3-RhoGEF of proteins in fruit fly might have evolved from SH3-RhoGEF-PH by the degeneration of PH domain.


Assuntos
Evolução Molecular , Fatores de Troca do Nucleotídeo Guanina/química , Fatores de Troca do Nucleotídeo Guanina/genética , Animais , Humanos , Filogenia , Estrutura Terciária de Proteína , Fatores de Troca de Nucleotídeo Guanina Rho
16.
Shi Yan Sheng Wu Xue Bao ; 36(3): 233-7, 2003 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-12966735

RESUMO

Genetic analyses of lifespan in model animals have revealed that extended lifespans are closely associated to increased resistance to oxidative stress. In the model plant Arabidopsis, late-flowering mutants are also found to be more tolerant to oxidative stress. However, Arabidopsis mutants with extended lifespans are poorly studied so far. In this study, a screening system for mutants with extended lifespans in Arabidopsis was established using paraquat, a potent herbicide that exacerbates O2-. radical production. The relationship between lifespan and resistance to oxidative stress was examined with one of the mutants, SFNA-9-4. Compared to that of wild type, the lifespan of SFNA-9-4 is significantly extended, and its resistance to oxidative stress is also significantly elevated. These results suggest that, as in Drosophila, paraquat can also be used to screen for mutants with extended lifespans in Arabidopsis.


Assuntos
Arabidopsis/crescimento & desenvolvimento , Arabidopsis/genética , Mutação , Paraquat/farmacologia , Animais , Arabidopsis/efeitos dos fármacos , Drosophila/genética , Regulação da Expressão Gênica de Plantas , Herbicidas/farmacologia , Estresse Oxidativo
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA