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1.
BMC Plant Biol ; 24(1): 542, 2024 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-38872107

RESUMO

BACKGROUND: Hydrogen gas (H2), a novel and beneficial gaseous molecule, plays a significant role in plant growth and development processes. Hydrogen-rich water (HRW) is regarded as a safe and easily available way to study the physiological effects of H2 on plants. Several recent research has shown that HRW attenuates stress-induced seed germination inhibition; however, the underlying modes of HRW on seed germination remain obscure under non-stress condition. RESULTS: In this current study, we investigated the possible roles of gibberellin (GA) and abscisic acid (ABA) in HRW-regulated seed germination in wax gourd (Benincasa hispida) through pharmacological, physiological, and transcriptome approaches. The results showed that HRW application at an optimal dose (50% HRW) significantly promoted seed germination and shortened the average germination time (AGT). Subsequent results suggested that 50% HRW treatment stimulated GA production by regulating GA biosynthesis genes (BhiGA3ox, BhiGA2ox, and BhiKAO), whereas it had no effect on the content of ABA and the expression of its biosynthesis (BhiNCED6) and catabolism genes (BhiCYP707A2) but decreased the expression of ABA receptor gene (BhiPYL). In addition, inhibition of GA production by paclobutrazol (PAC) could block the HRW-mediated germination. Treatment with ABA could hinder HRW-mediated seed germination and the ABA biosynthesis inhibitor sodium tungstate (ST) could recover the function of HRW. Furthermore, RNA-seq analysis revealed that, in the presence of GA or ABA, an abundance of genes involved in GA, ABA, and ethylene signal sensing and transduction might involve in HRW-regulated germination. CONCLUSIONS: This study portrays insights into the mechanism of HRW-mediated seed germination, suggesting that HRW can regulate the balance between GA and ABA to mediate seed germination through ethylene signals in wax gourd.


Assuntos
Ácido Abscísico , Germinação , Giberelinas , Hidrogênio , Reguladores de Crescimento de Plantas , Sementes , Transdução de Sinais , Giberelinas/metabolismo , Germinação/efeitos dos fármacos , Ácido Abscísico/metabolismo , Sementes/crescimento & desenvolvimento , Sementes/efeitos dos fármacos , Sementes/genética , Sementes/fisiologia , Reguladores de Crescimento de Plantas/metabolismo , Hidrogênio/metabolismo , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos
2.
Microb Cell Fact ; 23(1): 76, 2024 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-38461254

RESUMO

BACKGROUND: Aspergillus niger ATCC 20611 is an industrially important fructooligosaccharides (FOS) producer since it produces the ß-fructofuranosidase with superior transglycosylation activity, which is responsible for the conversion of sucrose to FOS accompanied by the by-product (glucose) generation. This study aims to consume glucose to enhance the content of FOS by heterologously expressing glucose oxidase and peroxidase in engineered A. niger. RESULTS: Glucose oxidase was successfully expressed and co-localized with ß-fructofuranosidase in mycelia. These mycelia were applied to synthesis of FOS, which possessed an increased purity of 60.63% from 52.07%. Furthermore, peroxidase was expressed in A. niger and reached 7.70 U/g, which could remove the potential inhibitor of glucose oxidase to facilitate the FOS synthesis. Finally, the glucose oxidase-expressing strain and the peroxidase-expressing strain were jointly used to synthesize FOS, which content achieved 71.00%. CONCLUSIONS: This strategy allows for obtaining high-content FOS by the multiple enzymes expressed in the industrial fungus, avoiding additional purification processes used in the production of oligosaccharides. This study not only facilitated the high-purity FOS synthesis, but also demonstrated the potential of A. niger ATCC 20611 as an enzyme-producing cell factory.


Assuntos
Aspergillus niger , Aspergillus , beta-Frutofuranosidase , Aspergillus niger/genética , Glucose Oxidase/genética , Oligossacarídeos , Peroxidases , Glucose
3.
Analyst ; 149(3): 836-845, 2024 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-38167890

RESUMO

With the vigorous development of biotechnology, genetically modified organisms (GMOs) have become more and more common. In order to effectively supervise and administrate them, the rapid and accurate detection of GMOs is urgently demanded. Here, GMO gene-specific sensing methods based on colorimetry and surface-enhanced Raman scattering (SERS) were proposed based on the lateral branch cleavage function of the CRISPR/Cas12a system. Two transgenes, pCaMV35S and M810 Cry1Ab, were chosen as targets for transgenic crops. By using these methods, we performed transgenic detection on five types of maize leaves and successfully distinguished transgenic from non-transgenic samples. The colorimetric method is rapid, economical and available for field detection. The SERS approach, giving a higher sensitivity to 100 fM, is more suitable for laboratory application scenarios. This study explores practical transgenic detection approaches and will be valuable for the supervision of GMOs.


Assuntos
Sistemas CRISPR-Cas , Zea mays , Plantas Geneticamente Modificadas/genética , Zea mays/genética , Sistemas CRISPR-Cas/genética , Transgenes
4.
Small ; 19(6): e2205962, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36461681

RESUMO

Wide-bandgap inorganic cesium lead halide CsPbIBr2 is a popular optoelectronic material that researchers are interested in because of the character that balances the power conversion efficiency and stability of solar cells. It also has great potential in semitransparent solar cells, indoor photovoltaics, and as a subcell for tandem solar cells. Although CsPbIBr2 -based devices have achieved good performance, the open-circuit voltage (Voc ) of CsPbIBr2 -based perovskite solar cells (PSCs) is still lower, and it is critical to further reduce large energy losses (Eloss ). Herein, a strategy is proposed for achieving surface p-type doping for CsPbIBr2 -based perovskite for the first time, using 1,5-Diaminopentane dihydroiodide at the perovskite surface to improve hole extraction efficiency. Meanwhile, the adjusted energy levels reduce Eloss and improve Voc of the CsPbIBr2 PSCs. Furthermore, the Cs- and Br-vacancies at the interface are filled, reducing structural disorder and defect states and thus improving the quality of the perovskite film. As a result, the target device achieves a high efficiency of 11.02% with a Voc of 1.33 V, which is among the best values. In addition to the improved performance, the stability of the target device under various conditions is enhanced, and the lead leakage is effectively suppressed.

5.
J Transl Med ; 21(1): 356, 2023 05 29.
Artigo em Inglês | MEDLINE | ID: mdl-37248471

RESUMO

BACKGROUND: Circular RNAs (circRNAs) are known to play a crucial role in a variety of malignancies. However, the precise role of circRNAs in cervical squamous cell carcinoma (CSCC) remains largely unknown. METHODS: The expression of circ0001955 was determined by real-time quantitative PCR and fluorescence in situ hybridization. To examine the effects of circ0001955 on CSCC metastasis and growth, functional experiments were conducted in vitro and in vivo. Mechanistically, nucleocytoplasmic separation, dual luciferase reporter assay, RNA antisense purification experiments, and rescue experiments were performed to confirm the interaction between circ0001955, miR-188-3p, and NCAPG2 in CSCC. RESULTS: Here, we demonstrated that a circRNA derived from the CSNK1G1 gene (circ0001955) is significantly upregulated in CSCC. The overexpression of circ0001955 promotes tumor proliferation and metastasis, whereas the knockdown of circ0001955 exerts the opposite effects. Mechanistically, circ0001955 competitively binds miR-188-3p and prevents miR-188-3p from reducing the levels of NCAPG2, activating the AKT/mTOR signaling pathway to induce epithelial mesenchymal transformation. Notably, the application of an inhibitor of mTOR significantly antagonized circ0001955-mediated CSCC tumorigenesis. CONCLUSION: circ0001955 promotes CSCC tumorigenesis and metastasis via the miR-188-3p/NCAPG2 axis which would provide an opportunity to search new therapeutic targets for CSCC.


Assuntos
MicroRNAs , Neoplasias do Colo do Útero , Feminino , Humanos , RNA Circular/genética , MicroRNAs/genética , MicroRNAs/metabolismo , Neoplasias do Colo do Útero/genética , Hibridização in Situ Fluorescente , Carcinogênese/genética , Transformação Celular Neoplásica/genética , Serina-Treonina Quinases TOR/metabolismo , Proliferação de Células/genética , Linhagem Celular Tumoral , Regulação Neoplásica da Expressão Gênica , Proteínas Cromossômicas não Histona/metabolismo
6.
Plant Cell Environ ; 46(1): 171-184, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36324267

RESUMO

Precocious leaf senescence can reduce crop yield and quality by limiting the growth stage. Melatonin has been shown to delay leaf senescence; however, the underlying mechanism remains obscure. Here, we show that melatonin offsets abscisic acid (ABA) to protect photosystem II and delay the senescence of attached old leaves under the light. Melatonin induced H2 O2 accumulation accompanied by an upregulation of melon respiratory burst oxidase homolog D (CmRBOHD) under ABA-induced stress. Both melatonin and H2 O2 induced the accumulation of cytoplasmic-free Ca2+ ([Ca2+ ]cyt ) in response to ABA, while blocking of Ca2+ influx channels attenuated melatonin- and H2 O2 -induced ABA tolerance. CmRBOHD overexpression induced [Ca2+ ]cyt accumulation and delayed leaf senescence, whereas deletion of Arabidopsis AtRBOHD, a homologous gene of CmRBOHD, compromised the melatonin-induced [Ca2+ ]cyt accumulation and delay of leaf senescence in Arabidopsis under ABA stress. Furthermore, melatonin, H2 O2  and Ca2+ attenuated ABA-induced K+ efflux and subsequent cell death. CmRBOHD overexpression and AtRBOHD deletion alleviated and aggravated the ABA-induced K+ efflux, respectively. Taken together, our study unveils a new mechanism by which melatonin offsets ABA action to delay leaf senescence via RBOHD-dependent H2 O2 production that triggers [Ca2+ ]cyt accumulation and subsequently inhibits K+ efflux and delays cell death/leaf senescence in response to ABA.


Assuntos
Arabidopsis , Melatonina , Ácido Abscísico/farmacologia , Melatonina/farmacologia , Cálcio , Arabidopsis/genética , Senescência Vegetal
7.
Org Biomol Chem ; 21(40): 8054-8074, 2023 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-37801029

RESUMO

Heterocyclic compounds, both naturally derived and synthetically produced, constitute a wide variety of biologically active and industrially important compounds. The synthesis and application of heterocyclic compounds have garnered significant attention and experienced rapid growth in recent decades. Organic azides, due to their unique properties and distinctive reactivity, have become a convenient chemical tool for achieving a wide range of heterocycles such as triazoles and tetrazoles. Importantly, the field of multicomponent reaction (MCR) chemistry provides a convergent approach to access various N-heterocyclic scaffolds, offering novelty, diversity, and complexity. However, the exploration of MCR pathways to N-heterocyclic compounds remains incomplete. Here, we review the use of multicomponent reactions for the preparation of N-heterocycles. A wide range of reactions based on azides for the synthesis of various types of N-heterocyclic systems have been developed.

8.
Int J Mol Sci ; 24(10)2023 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-37240100

RESUMO

SPX-domain proteins (small proteins with only the SPX domain) have been proven to be involved in phosphate-related signal transduction and regulation pathways. Except for OsSPX1 research showing that it plays a role in the process of rice adaptation to cold stress, the potential functions of other SPX genes in cold stress are unknown. Therefore, in this study, we identified six OsSPXs from the whole genome of DXWR. The phylogeny of OsSPXs has a strong correlation with its motif. Transcriptome data analysis showed that OsSPXs were highly sensitive to cold stress, and real-time PCR verified that the levels of OsSPX1, OsSPX2, OsSPX4, and OsSPX6 in cold-tolerant materials (DXWR) during cold treatment were higher than that of cold-sensitive rice (GZX49). The promoter region of DXWR OsSPXs contains a large number of cis-acting elements related to abiotic stress tolerance and plant hormone response. At the same time, these genes have expression patterns that are highly similar to cold-tolerance genes. This study provides useful information about OsSPXs, which is helpful for the gene-function research of DXWR and genetic improvements during breeding.


Assuntos
Oryza , Oryza/fisiologia , Melhoramento Vegetal , Perfilação da Expressão Gênica , Transcriptoma , Estresse Fisiológico/genética , Regulação da Expressão Gênica de Plantas , Temperatura Baixa
9.
Yi Chuan ; 45(1): 52-66, 2023 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-36927638

RESUMO

As an effective supplement to the current forensic DNA typing and one of the research hotpots in forensic science, the in-depth mining and characterization of biological evidence can provide rich and reliable clues for case investigation. In this study, the time-dependent variations of transcriptome were confirmed in in vitro blood samples within 0-168 days and a random forest model was established to realize the classification of blood samples with different TSD (time since deposition). Meanwhile, significant differences were observed in the transcripts of blood samples with different smoking habits and genders within a certain time period. HLA-DRB1, HLA-DQB1 and HLA-DQA2 were identified as markers for smoking habit identification, while the transcripts for RPS4Y1 and EIF1AY from the non-recombining region of the Y chromosome (NRY) were identified as markers for male sex identification. Thus, this study provides a theoretical foundation and experimental strategy for establishing a transcriptome-based method for characterizing blood sample retention time and donor characteristics in the field of forensic investigation.


Assuntos
Transcriptoma , Humanos , Masculino , Feminino , Cadeias HLA-DRB1/genética , Reação em Cadeia da Polimerase , Alelos
10.
Fa Yi Xue Za Zhi ; 39(1): 40-44, 2023 Feb 25.
Artigo em Inglês, Zh | MEDLINE | ID: mdl-37038854

RESUMO

OBJECTIVES: To establish a rapid and nondestructive identification method for human body fluid stains and non-biological stains using three-dimensional fluorescence spectroscopy. METHODS: The collected three-dimensional fluorescence spectrum data of human saliva, 3% blood, coffee and Fanta® stains were processed with dimensionality reduction. After wavelet transform, spectral denoising and feature extraction, the classification formula was established. The Fisher discriminant was used for spectrum matching and recognition to establish the analysis method to distinguish stain types. RESULTS: According to the results of data training and comparison, all the recognition accuracies of Fanta®, coffee, saliva and blood were more than 91.39%. Among them, saliva reached 100% recognition accuracy. CONCLUSIONS: Three-dimensional fluorescence spectroscopy is a potential method for rapid and nondestructive identification of biological and non-biological stains.


Assuntos
Líquidos Corporais , Medicina Legal , Humanos , Medicina Legal/métodos , Corantes/análise , Café , Espectrometria de Fluorescência , Líquidos Corporais/química
11.
Angew Chem Int Ed Engl ; 62(18): e202300678, 2023 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-36748289

RESUMO

Rationally managing the secondary-phase excess lead iodide (PbI2 ) in hybrid perovskite is of significance for pursuing high performance perovskite solar cells (PSCs), while the challenge remains on its conversion to a homogeneous layer that is robust stable against environmental stimuli. We herein demonstrate an effective strategy of surface reconstruction that converts the excess PbI2 into a gradient lead sulfate-silica bi-layer, which substantially stabilizes the perovskite film and reduces interfacial charge transfer barrier in the PSCs device. The perovskite films with such bi-layer could bear harsh conditions such as soaking in water, light illumination at 70 % relative humidity, and the damp-thermal (85 °C and 30 % humidity) environment. The resulted PSCs deliver a champion efficiency up to 24.09 %, as well as remarkable environmental stability, e.g., retaining 78 % of their initial efficiency after 5500 h of shelf storage, and 82 % after 1000 h of operational stability testing.

12.
Angew Chem Int Ed Engl ; 62(33): e202306229, 2023 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-37338503

RESUMO

Perovskite solar cells (PSCs) are considered as a promising photovoltaic technology due to their high efficiency and low cost. However, their long-term stability, mechanical durability, and environmental risks are still unable to meet practical needs. To overcome these issues, we designed a multifunctional elastomer with abundant hydrogen bonds and carbonyl groups. The chemical bonding between polymer and perovskite could increase the growth activation energy of perovskite film and promote the preferential growth of high-quality perovskite film. Owing to the low defect density and gradient energy-level alignment, the corresponding device exhibited a champion efficiency of 23.10 %. Furthermore, due to the formation of the hydrogen-bonded polymer network in the perovskite film, the target devices demonstrated excellent air stability and enhanced flexibility for the flexible PSCs. More importantly, the polymer network could coordinate with Pb2+ ions, immobilizing lead atoms to reduce their release into the environment. This strategy paves the way for the industrialization of high-performance flexible PSCs.

13.
BMC Genomics ; 22(1): 278, 2021 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-33865333

RESUMO

BACKGROUND: Rice, which serves as a staple food for more than half of the world's population, is grown worldwide. The hybridization of wild and cultivated rice has enabled the incorporation of resistance to varying environmental conditions. Endophytic microbiota are known to be transferred with their host plants. Although some studies have reported on the endophytic microbiota of wild and cultivated rice, the inheritance from wild and cultivated rice accessions in next generations, in terms of endophytic microbiota, has not been examined. RESULTS: In the present study, the endophytic microbial community structures of Asian and African wild and cultivated rice species were compared with those of their F1 offspring. High-throughput sequencing data of bacterial 16S rDNA and fungal internal transcribed spacer regions were used to classify the endophytic microbiota of collected samples of rice. Results indicated that when either African or Asian wild rice species were crossed with cultivated rice accessions, the first generation harbored a greater number of root endophytic fungi than the cultivated parent used to make the crosses. Network analysis of the bacterial and fungal operational taxonomic units revealed that Asian and African wild rice species clustered together and exhibited a greater number of significant correlations between fungal taxa than cultivated rice. The core bacterial genus Acidovorax and the core fungal order Pleosporales, and genera Myrothecium and Bullera connected African and Asian wild rice accessions together, and both the wild rice accessions with their F1 offspring. On the other hand, the core bacterial genus Bradyrhizobium and the core fungal genera Dendroclathra linked the African and Asian cultivated rice accessions together. CONCLUSIONS: This study has theoretical significance for understanding the effect of breeding on the inheritance of endophytic microbiota of rice and identifying beneficial endophytic bacteria and fungi among wild and cultivated rice species, and their F1 offspring.


Assuntos
Oryza , Fungos/genética , Hibridização Genética , Oryza/genética , Melhoramento Vegetal , Raízes de Plantas/genética
14.
BMC Cancer ; 21(1): 804, 2021 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-34253177

RESUMO

BACKGROUND: In the absence of practical and reliable predictors for whether the endocervical curettage (ECC) procedure should be performed, decisions regarding patient selection are usually based on the colposcopists' clinical judgment instead of evidence. We aimed to develop and validate a practical prediction model that uses available information to reliably estimate the need to perform ECC in patients suspected of having cervical lesions. METHODS: In this retrospective study, 2088 patients who underwent colposcopy, colposcopically directed biopsy (CDB) and ECC procedures between September 2019 and September 2020 at the Second Hospital of Shanxi Medical University were included. The data were analyzed with univariate and multivariable logistic regression. Least absolute shrinkage and selection operator (LASSO) was used to select predictors for ECC positivity. The ECC prediction model was presented as a nomogram and evaluated in terms of discrimination and calibration. Furthermore, this model was validated internally with cross-validation and bootstrapping. RESULTS: Significant trends were found for ECC positivity with increasing age (P = 0.001), menopause (P = 0.003), Human papillomavirus (HPV) status (P < 0.001), severity of ThinPrep Cytological Test (TCT) (P < 0.001), original squamous epithelium ectopia (P = 0.037) and colposcopy impression (P < 0.001) by multivariable logistic regression analysis. The ECC prediction model was developed based on the following predictors: age, menopause, symptom of contact bleeding, severity of TCT, HPV status, cervix visibility, original squamous epithelium ectopia, acetowhite changes and colposcopic impression. This model had satisfactory calibration and good discrimination, with an area under the receiver operator characteristic curve (AUC) of 0.869 (95% confidence interval 0.849 to 0.889). CONCLUSIONS: A readily applicable clinical prediction model was constructed to reliably estimate the probability of ECC positivity in patients suspicious of having cervical lesions, which may help clinicians make decisions regarding the ECC procedure and possibly prevent adverse effects.


Assuntos
Biópsia/métodos , Colposcopia/métodos , Curetagem/métodos , Neoplasias do Colo do Útero/cirurgia , Adulto , Tomada de Decisões , Feminino , Humanos , Pessoa de Meia-Idade , Prognóstico , Estudos Retrospectivos , Neoplasias do Colo do Útero/patologia
15.
Arch Microbiol ; 203(5): 2157-2170, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33616683

RESUMO

Soil physicochemical properties and fungal communities are pivotal factors for continuous cropping of American ginseng (Panax quinquefolium L.). However, the response of soil physicochemical properties and fungal communities to replant disease of American ginseng has not yet been studied. High-throughput sequencing and soil physicochemical analyses were undertaken to investigate the difference of soil fungal communities and environmental driver factors in new and old ginseng fields; the extent of replant disease in old ginseng fields closely related to changes in soil properties and fungal communities was also determined. Results indicated that fungal communities in an old ginseng field were more sensitive to the soil environment than those in a new ginseng field, and fungal communities were mainly driven by soil organic matter (SOM), soil available phosphorus (AP), and available potassium (AK). Notably, healthy ginseng plants in new and old ginseng fields may influence fungal communities by actively recruiting potential disease suppressive fungal agents such as Amphinema, Cladophialophora, Cadophora, Mortierella, and Wilcoxina. When these key groups and members were depleted, suppressive agents in the soil possibly declined, increasing the abundance of pathogens. Soil used to grow American ginseng in the old ginseng field contained a variety of fungal pathogens, including Alternaria, Armillaria, Aphanoascus, Aspergillus, Setophoma, and Rhexocercosporidium. Additionally, micro-ecological factors affecting disease outbreaks in the old ginseng field included a strengthening in competition relationships, a weakening in cooperation relationships, and a change of trophic strategies among fungal communities.


Assuntos
Fungos/genética , Micobioma/genética , Panax/microbiologia , Doenças das Plantas/microbiologia , Surtos de Doenças , Fungos/classificação , Sequenciamento de Nucleotídeos em Larga Escala , Solo/química , Microbiologia do Solo
16.
Pharmacol Res ; 165: 105464, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33515707

RESUMO

BACKGROUND: An individual's level of lower limb motor function is associated with his or her disability level after stroke, and motor improvement may lead to a better prognosis and quality of life. Data from animal models show that Qizhitongluo (QZTL) capsule facilitates recovery after focal brain injury. We aimed to validate the efficacy and safety of the QZTL capsule for promoting lower limb motor recovery in poststroke patients. METHODS: In this randomized, multicenter, double-blind, placebo- and active-controlled trial from 13 sites in China, participants with ischemic stroke and Fugl-Meyer motor scale (FMMS) scores of <95 were eligible for inclusion. Patients were randomly assigned in a 2:1:1 ratio to the QZTL group, Naoxintong (NXT) group or placebo group for 12 weeks at 15-28 days after the onset of stroke. The primary outcome was the change in the Lower Limb FMMS (FMMS-LL) score from baseline over the 12-week intervention period. RESULTS: 622 participants were randomly assigned to the QZTL group (309), NXT group (159), or placebo group (154). The FMMS-LL score increased by 4.81 points (95 % CI, 4.27-5.35) in the QZTL group, by 3.77 points (95 % CI, 3.03-4.51) in the NXT group and by 3.00 points (95 % CI, 3.03-4.51) in the placebo group at week 12. The QZTL group showed significantly larger improvements compared with the placebo group at each interview from weeks 4-12 (difference, 0.89 [0.30,1.49] at week 4, P = 0.0032; difference, 1.83[1.01,2.66] at 90 days poststroke, P < 0.0001; difference, 1.81[0.88,2.74] at week 12, P = 0.0001). CONCLUSION: The QZTL capsule is an effective treatment for lower limb motor impairment. The finding indicates that the QZTL capsule may be used as a potential new strategy for stroke rehabilitation.


Assuntos
Medicamentos de Ervas Chinesas/uso terapêutico , Extremidade Inferior/fisiologia , Reabilitação do Acidente Vascular Cerebral/métodos , Acidente Vascular Cerebral/diagnóstico , Acidente Vascular Cerebral/terapia , Idoso , Cápsulas , Método Duplo-Cego , Medicamentos de Ervas Chinesas/farmacologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Recuperação de Função Fisiológica/efeitos dos fármacos , Recuperação de Função Fisiológica/fisiologia , Acidente Vascular Cerebral/fisiopatologia , Resultado do Tratamento
17.
Phys Chem Chem Phys ; 23(10): 5975-5983, 2021 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-33666617

RESUMO

ß-Ga2O3 has recently attracted considerable attention for its application in resistive switching memory. However, the resistive behaviors and mechanisms of ß-Ga2O3 memory dominated by the oxygen-vacancy (VO) still remain controversial. In this study, we systemically investigated the formation process of VO conductive filaments in ß-Ga2O3 memory. There were at least three kinds of VOs and conductive filaments with different low resistance states (LRSs) in ß-Ga2O3 memory, suggesting their potential for multilevel storage application. Interestingly, these conductive filaments preferred to be formed along the [010] direction and with a single VO cluster rather than a mixed VO cluster due to the lower single VO cluster formation energy and ellipsoid charge distribution. The lowest migration and activation barriers for different kinds of VOs in +2 charge states (V2+Os) were discrepant and lower than the neutral charge states. Meanwhile, the forward migration energy of VO was different from the reversed migration path, so that the conductive filament formation and rupture were not an inverse process in the experiment. The detailed mechanisms were revealed by the charge density and migration process of these VOs. These results not only revealed the function of the VO conductive filaments in ß-Ga2O3 memory but also predicted the potential of ß-Ga2O3 memory for multilevel storage application.

18.
Neuroimage ; 204: 116212, 2020 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-31546050

RESUMO

Life stress has been shown to impact cognitive functions, including inhibitory control. However, the immediate effects of acute stress on inhibitory control and the underlying neural mechanisms remain unclear. In a behavioral pilot study (N = 30) and a within-subject functional magnetic resonance imaging study (N = 30), we examined how acute stress induced by Trier Social Stress Test influenced inhibitory control in a stop signal task. Behavioral results across two studies showed that stress consistently improved inhibitory control. Shorter stop signal reaction time (SSRT) in stress as compared with control condition was associated with stronger connectivity between the superior/middle frontal gyrus (SFG/MFG) and striatum. Dynamic causal modeling revealed distinct best models under stress and control condition, with an enhanced interaction between the SFG/MFG and the striatum after stress exposure. This research identified the SFG/MFG-striatum network as a key circuit underlying acute stress-elicited enhancement of inhibitory control in a stop signal task.


Assuntos
Conectoma , Corpo Estriado/fisiologia , Função Executiva/fisiologia , Inibição Psicológica , Rede Nervosa/fisiologia , Córtex Pré-Frontal/fisiologia , Desempenho Psicomotor/fisiologia , Tempo de Reação/fisiologia , Estresse Psicológico/fisiopatologia , Adulto , Corpo Estriado/diagnóstico por imagem , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Rede Nervosa/diagnóstico por imagem , Projetos Piloto , Córtex Pré-Frontal/diagnóstico por imagem , Estresse Psicológico/diagnóstico por imagem , Adulto Jovem
19.
Nanotechnology ; 31(48): 485204, 2020 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-32931467

RESUMO

Modulating the n- and p-type interfacial charge transport properties of the metal-semiconductor interface is vital to realizing high performance two-dimensional material nanodevices and is still a significant challenge. Here, a boron nitride (BN)-graphene lateral heterostructure (LH) was used as the interfacial tunneling layer to control the Schottky barrier, Fermi level pinning and charge injection efficiency of the metal-MoS2 interface. The BN-graphene LH with graphene-N junction structure decreased the n-type vertical Schottky barrier and enhanced the interfacial tunneling probability, while the graphene-B junction structure decreased the p-type vertical Schottky barrier. Consequently, the n-type Au/LH-MoS2 interface with Ohmic character and high tunneling probability (∼0.242) and the p-type vertical Schottky barrier of about 0.20 eV for the Pt/LH-MoS2 interface were achieved. Compared to other reported BN or graphene tunneling layers, such a BN-graphene LH tunneling layer not only suppressed the charge scattering from the metal electrode to the MoS2 layer and the Fermi level pinning effect, but also reduced the contact resistance between metal electrode and tunneling layer. The underlying mechanisms were revealed to be due to the charge transfer, orbitals and interfacial dipole. This work improves the current understanding of the metal-MoS2 interface and proposes a new way to overcome the current severe contact issues for future nanoelectronic and optoelectronic applications.

20.
J Am Chem Soc ; 141(5): 2169-2176, 2019 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-30632366

RESUMO

Extension of oxygen-embedded polycyclic aromatic hydrocarbons (PAHs), in particular with a defined topology, is synthetically challenging primarily because of limited regio-specific methods and poor solubility of PAHs. We reported herein an efficient way to construct quinoidal pentacenes and nonacenes with regular zigzag O-inserted edges. These O-embedded backbones composed of benzene, pyranyl, and cyclohexa-1,4-diene moieties provided access to a new class of longitudinally conjugated acenes with superior stability. Their structures, confirmed by single-crystal XRD analysis, indicated that they possessed rich hydrogen/halogen-bonding interactions, which likely contribute to the strengthened aggregation. In contrast to many other O-annulated PAHs generally displaying short-absorption wavelengths due to partially interrupted electron communication, the O-embedded quinoidal acene exhibited highly red-shifted absorptions (up to ∼699 nm) and narrowed energy gaps (down to ∼1.5 eV). As with more O-containing rings and quinoidal subunits in the backbone, the conjugation size was enlarged, and the molar absorption coefficients (ε) of the λmax significantly increased further, in particular, a noticeable lower-energy peak at ∼790 nm for O-doping nonacenes N1-OH/OMe. By the thin-film-based organic field-effect transistor measurements, the relatively ordered O-doping pentacene P1-OMe possessed a hole transporting efficiency (µh) of 0.00406 cm-2 V-1 s-1 in in-air fabricated devices, while O-pentacene P1-PFB with two perfluorobutoxyl substituents witnessed an improved µh up to 0.0152 cm-2 V-1 s-1. In addition, one- or two-electron oxidation of O-pentacene/nonacene generated the corresponding radical cations or dications, in which electronic properties were dependent on the number of O-containing six-membered rings and quinoidal subunits. The study provided insights into the relationships between molecule structures and optoelectronic properties for the unique class of O-embedded PAHs.

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