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1.
Protoplasma ; 261(2): 351-366, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37906315

RESUMO

Grape (Vitis L.), a highly valued fruit crop, poses significant challenges in genetic transformation and functional characterization of genes. Therefore, there is an urgent need for the development of a rapid and effective method for grape transformation and gene function identification. Here, we introduce a streamlined Agrobacterium-mediated transient transformation system for grape calli. Optimal conditions were established with a leaf-derived callus induction medium; chiefly B5 medium supplemented with 0.05 mg/L NAA, 0.5 mg/L 2,4-D, and 2.0 mg/L KT; and a callus proliferation medium (B5 medium supplemented with 0.5 mg/L NAA and 2.0 mg/L 6-BA), respectively. Notably, GUS enzyme activity peaked (352.96 ± 33.95 mol 4-MU/mg/min) by sonication with Agrobacterium tumefaciens EHA105 and 100 µM AS for 4 min, followed by vacuum infection for 5 min, and co-culture at 25 °C in the dark for 1 day using callus as explants at an optical density (OD600) of 0.8. VaCIPK18 gene was transiently transformed into calli, and transcripts of the gene (endogenous and exogenous) were detected at higher levels than in non-transformed calli (endogenous). Moreover, after 10 days of treatment at 4 °C or -4 °C, the callus net weight of transformed callus was significantly higher than that of the untransformed callus, indicating that the VaCIPK18-overexpressing grape callus could improve cold tolerance. Overall, we establish a simple but effective transient transformation approach for grape callus, which could serve as a useful tool for the rapid assessment of gene function in this important crop.


Assuntos
Vitis , Vitis/genética , Plantas Geneticamente Modificadas/genética , Transformação Genética , Agrobacterium tumefaciens/genética
2.
J Clin Nurs ; 33(2): 531-542, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37881110

RESUMO

AIMS AND OBJECTIVES: To develop and validate a behavioural driving model for adherence to home-based cardiac rehabilitation exercise in patients with chronic heart failure, and to explain the potential driving mechanism of social support on exercise adherence. BACKGROUND: Despite the benefits of home-based cardiac rehabilitation exercise, adherence among patients with chronic heart failure remains suboptimal. Several factors contributing to adherence have been confirmed; however, the specific pathway mechanisms by which these factors impact exercise adherence have not been thoroughly explored. DESIGN: An exploratory sequential mixed-methods study was conducted in this study. METHODS: A total of 226 patients with chronic heart failure were recruited using convenience sampling. Quantitative data were collected using a series of self-report questionnaires. Hierarchical regression analysis was performed to verify multiple pathways. Subsequently, 12 patients with chronic heart failure were drawn from the quantitative stage. The interview data were thematically analysed. This study followed the Good Reporting of a Mixed Methods Study (GRAMMS) guidelines (Appendix S1). RESULTS: Perceived social support had a direct positive predictive effect on exercise adherence. Importantly, exercise self-efficacy and exercise fear played a chain-mediating role between perceived social support and exercise adherence. As a result of the qualitative phase, scale, tightness and homogeneity of social support networks emerged as potential drivers of the effectiveness of social support on exercise adherence. CONCLUSIONS: This study reveals a potential pathway mechanism for social support to improve adherence to home-based cardiac rehabilitation exercises. Social support network plays a crucial role in the effect of social support on exercise adherence. RELEVANCE TO CLINICAL PRACTICE: To enhance exercise adherence in home-based cardiac rehabilitation for patients with chronic heart failure, establishing a social support network is recommended. This strategy has the potential to promote exercise self-efficacy and alleviate exercise fear. PATIENT OR PUBLIC CONTRIBUTION: None.


Assuntos
Reabilitação Cardíaca , Insuficiência Cardíaca , Humanos , Terapia por Exercício/métodos , Exercício Físico , Doença Crônica
3.
BMC Plant Biol ; 23(1): 611, 2023 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-38041099

RESUMO

BACKGROUND: GATA transcription factors are type IV zinc-finger proteins that play key roles in plant growth and responses to environmental stimuli. Although these proteins have been studied in model plants, the related studies of GATA gene family under abiotic stresses are rarely reported in grapevine (Vitis vinifera L.). RESULTS: In the current study, a total of 23 VviGATA genes were identified in grapevine and classified into four groups (I, II, III, and IV), based on phylogenetic analysis. The proteins in the same group exhibited similar exon-intron structures and conserved motifs and were found to be unevenly distributed among the thirteen grapevine chromosomes. Accordingly, it is likely that segmental and tandem duplication events contributed to the expansion of the VviGATA gene family. Analysis of cis-acting regulatory elements in their promoters suggested that VviGATA genes respond to light and are influenced by multiple hormones and stresses. Organ/tissue expression profiles showed tissue specificity for most of the VviGATA genes, and five were preferentially upregulated in different fruit developmental stages, while others were strongly induced by drought, salt and cold stress treatments. Heterologously expressed VamGATA5a, VamGATA8b, VamGATA24a, VamGATA24c and VamGATA24d from cold-resistant V. amurensis 'Shuangyou' showed nuclear localization and transcriptional activity was shown for VamGATA5a, VamGATA8b and VamGATA24d. CONCLUSIONS: The results of this study provide useful information for GATA gene function analysis and aid in the understanding of stress responses in grapevine for future molecular breeding initiatives.


Assuntos
Fatores de Transcrição GATA , Vitis , Fatores de Transcrição GATA/genética , Fatores de Transcrição GATA/metabolismo , Vitis/metabolismo , Filogenia , Regiões Promotoras Genéticas/genética , Estresse Fisiológico/genética , Regulação da Expressão Gênica de Plantas , Proteínas de Plantas/metabolismo , Família Multigênica
4.
Lett Appl Microbiol ; 76(9)2023 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-37656884

RESUMO

Fusarium head blight (FHB) is a wheat disease caused by the plant pathogen Fusarium graminearum, which leads to crop yield losses and agricultural economic losses, as well as poses a threat to the environment and human health. Effective biocontrol of F. graminearum is urgent. An antagonistic strain HZ-5 with 59.2% antagonistic activity against F. graminearum in vitro had been isolated from sea mud of Haizhou Bay using a dual-culture assay, which was highly homologous with Bacillus halosaccharovorans according to the 16S rRNA sequence. The antagonistic activity of HZ-5 had been further studied. HZ-5 had a broad range of antagonistic activity against another six plant pathogenic fungi and was effective in controlling FHB of wheat in pot experiment. The substances with antagonistic activity were temperature insensitive, and had been purified by HPLC (High Performance Liquid Chromatography) to prove to be secreted lipopeptides. The antagonistic substances induced the biosynthesis of chitin and glycerol, while ergosterol , cholesterol, and phosphatidylcholine reduced their inhibitory effects on F. graminearum. These data would be helpful to provide a better biocontrol strain against FHB, and to provide important basis to elucidate the antagonistic mechanism of biocontrol.


Assuntos
Bacillus , Fusarium , Humanos , RNA Ribossômico 16S/genética , Glicerol
5.
NPJ Biofilms Microbiomes ; 9(1): 46, 2023 07 05.
Artigo em Inglês | MEDLINE | ID: mdl-37407614

RESUMO

The soil microbiota is critical to plant performance. Improving the ability of plant-associated soil probiotics is thus essential for establishing dependable and sustainable crop yields. Although fertilizer applications may provide an effective way of steering soil microbes, it is still unknown how the positive effects of soil-borne probiotics can be maximized and how their effects are mediated. This work aims to seek the ecological mechanisms involved in cabbage growth using bio-organic fertilizers. We conducted a long-term field experiment in which we amended soil with non-sterilized organic or sterilized organic fertilizer either containing Trichoderma guizhouense NJAU4742 or lacking this inoculum and tracked cabbage plant growth and the soil fungal community. Trichoderma-amended bio-organic fertilizers significantly increased cabbage plant biomass and this effect was attributed to changes in the resident fungal community composition, including an increase in the relative abundance and number of indigenous soil growth-promoting fungal taxa. We specifically highlight the fundamental role of the biodiversity and population density of these plant-beneficial fungal taxa in improving plant growth. Together, our results suggest that the beneficial effects of bio-organic fertilizer seem to be a combination of the biological inoculum within the organic amendment as well as the indirect promotion through effects on the diversity and composition of the soil resident plant-beneficial fungal microbiome.


Assuntos
Solo , Trichoderma , Fertilizantes/análise , Microbiologia do Solo , Biodiversidade
6.
Front Psychol ; 13: 971700, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36248443

RESUMO

White LEDs, which have been widely used in the urban street lighting, are increasingly applied to replace traditional HPS lamps with a lower CCT (correlated color temperature). Generally, studies on the CCT of street lighting focus on providing safe functional lighting for vehicle drivers. However, it is still unknown how the street light color can affect pedestrians' perception and preferences with respect to lighting levels and ambient temperature. In this study, a wide range of CCTs (1,600-5,400 K) was measured for urban street lighting in Beijing, China, for example. And the transition from traditional HPS lamps to LEDs lacks a reference street lighting standard for CCT. The study aims to conduct a cross-sensory test to evaluate urban street lighting with multiple combinations of CCT values and illuminance levels according to pedestrians' visual perception and psychological preferences. A total of 18 night street lighting scenes with six CCT values and three illuminance levels were first selected in Beijing city, and then HDR videos of these scenes were taken from the view of pedestrians to conduct psychological experiments in an indoor environment with three ambient temperatures. A total of 77 university students (24 males) were invited to assess videos of the 18 lighting scenes in terms of seven factors, such as lighting brightness, color temperature sensation, light color preference, sense of safety, recognition, comfort, and overall preference. Several key findings were achieved as follows. (1) The CCT of urban street lighting can have significant effects on the visual psychological perceptions of participants. (2) There was a significant interaction between CCT, illuminance, and ambient temperature on the visual psychological performances of participants. (3) The higher ambient temperature will deliver the higher level of overall preference for the street lighting with medium and high CCT, and the perception of warmer light color. (4) There was a strong correlation found between participants' light color preference, comfort, and overall preferences.

7.
J Orthop Surg Res ; 17(1): 443, 2022 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-36207755

RESUMO

BACKGROUND: Medical devices are used in almost all orthopedic surgical subspecialties, and the frequency of adverse events is increasing, which should not be ignored. To provide suggestions on how to avoid implant recalls from the perspective of manufacturers, medical institutions and supervisions, as well as how to respond promptly to adverse events. METHODS: The research extracted recalls of osteosynthesis implants and joint replacement implants from January 1, 2011, to June 30, 2021, in the CNMPA, FDA, HC and ATGA websites and collected the information on device name, recall time, recall class, recall manufacturer, device classification and affected areas. Moreover, the McKinsey 7S model and fishbone diagram were used to analyze recall reasons. RESULTS: A total of 315 cases of osteosynthesis implants and 286 cases of joint replacement implants were reported in China, the USA, Canada and Australia. The recalls number from 2016 to 2021 was more than that from 2011 to 2015 for osteosynthesis implant (p = 0.012) and joint replacement implant (p = 0.002), and both mainly focused on class II (76.19% and 78.32%). There were statistical differences in the four countries for both implants (p = 0.000), especially osteosynthesis implant between China and the USA (p = 0.000), China and Canada (p = 0.001), the USA and Australia (p = 0.002), and joint replacement implant between China and Australia (p = 0.000). CONCLUSIONS: To avoid the recalls of such implants, manufacturers should strictly select implant materials and components, develop detailed labels and instructions, severely control the packaging process and establish the integrity of medical device data. Medical institutions should standardize procurement procedures, use qualified equipment and train medical workers. It also requires supervisions to conduct premarket safety assessments. In addition, regulators should strengthen supervision and establish reporting systems to deal with the occurrence of adverse events promptly.


Assuntos
Artroplastia de Substituição , Recall de Dispositivo Médico , Austrália , Humanos , Próteses e Implantes , Reoperação
8.
Hortic Res ; 2022 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-35039817

RESUMO

Grapevine leafroll-associated virus 3 (GLRaV-3) is one of the causal agents of grapevine leafroll disease (GLD), which severely impacts grapevine production in most viticultural regions of the world. The development of virus-resistant plants is a desirable strategy for the efficient control of viral diseases. However, natural resistant resources have not been reported in the genus Vitis, and anti-GLRaV-3 research has been quite limited in grapevine. In this study, by expressing FnCas9 and LshCas13a, we established a highly effective transgenic construct screening system via an optimized Agrobacterium-mediated transient delivery system in grapevine plantlets. Our study indicated that CRISPR/FnCas9 and LshCas13a caused GLRaV-3 inhibition. Moreover, three vectors-pCR01-CP, pCR11-Hsp70h and pCR11-CP-exhibited the most robust inhibition efficiency compared to those targeting other sites and could be further engineered to generate GLRaV-3-resistant grapevine. In addition, the viral interference efficiency of FnCas9 was dependent on its RNA binding activity. The efficiency of virus inhibition was positively correlated with the level of Cas gene expression. Importantly, we demonstrated that LshCas13a had better interference efficiency against viruses than FnCas9. In summary, this study confirmed that these two RNA-targeting CRISPR mechanisms can confer immunity against viruses in grapevine, providing new avenues to control GLRaV-3 or other RNA viruses in fruit crops.

9.
BMJ Open ; 11(6): e043711, 2021 06 14.
Artigo em Inglês | MEDLINE | ID: mdl-34127488

RESUMO

OBJECTIVE: This study aimed to develop and validate a new Learning Behaviour Questionnaire (LBQ) for the undergraduate nursing students. STUDY DESIGN: This study was performed in two phases. Phase 1 of the study focused on questionnaire development to create a pool of items, while phase 2 focused on validity and reliability testing. METHODS: Semistructured interviews were used to explore nursing undergraduates' perception of learning behaviour. A two-round modified Delphi method was used to test content validity and quantify the degree of consistency in questionnaire items. An item analysis, an exploratory factor analysis (EFA), a confirmatory factor analysis (CFA) and an internal consistency reliability check were conducted. Criterion-related validity was demonstrated through correlations with Self-Regulated Learning Scale for Undergraduates (SRLS-U). A sample of 114 nursing students was evaluated in test-retest reliability to confirm stability. RESULTS: The final LBQ consisted of four factors for the 19-item questionnaire with a 5-point rating from '1' (Fully disagree) to '5' (fully agree). The content validity was 0.890. EFA revealed the presence of four factors, including 'strategy', 'attitude', 'motivation' and 'degree of satisfaction'. The CFA indicated good fit indexes for the proposed model (χ2/df=1.866, root mean square residual=0.037, comparative fit index =0.950, goodness-of-fit index =0.929, Tucker-Lewis index=0.941, adjusted goodness-of-fit index=0.907 and root mean square error of approximation=0.049). The LBQ correlated significantly with SRLS-U subscales (r=0.742-0.837, p<0.01). The Cronbach's alpha coefficient of the whole questionnaire was 0.936, while the Cronbach's alphas of the four factors were 0.828, 0.826, 0.804 and 0.805, respectively. The test-retest reliabilities of the four factors were 0.886, 0.904, 0.852 and 0.875, respectively. CONCLUSION: The validity and reliability of the LBQ were satisfying. The LBQ is a short, well-developed questionnaire that can serve as a generic assessment tool for measuring learning behaviour for Chinese undergraduate nursing students.Cite Now.


Assuntos
Bacharelado em Enfermagem , Estudantes de Enfermagem , China , Análise Fatorial , Humanos , Psicometria , Reprodutibilidade dos Testes , Inquéritos e Questionários
10.
Plant Methods ; 14: 87, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30323856

RESUMO

Production of virus-free plants is necessary to control viral diseases, import novel cultivars from other countries, exchange breeding materials between countries or regions and preserve plant germplasm. In vitro techniques represent the most successful approaches for virus eradication. In vitro thermotherapy-based methods, including combining thermotherapy with shoot tip culture, chemotherapy, micrografting or shoot tip cryotherapy, have been successfully established for efficient eradication of various viruses from almost all of the most economically important crops. The present study reviewed recent advances in in vitro thermotherapy-based methods for virus eradication since the twenty-first century. Mechanisms as to why thermotherapy-based methods could efficiently eradicate viruses were discussed. Finally, future prospects were proposed to direct further studies.

11.
Cryobiology ; 84: 52-58, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-30092171

RESUMO

Plant cryopreservation has provide secure back-ups of germplasm collections of vegetatively propagated crops. Often, recovery levels vary among laboratories when the same cryogenic procedures are used for the same genotypes. The present study investigated the effects of Apple stem grooving virus (ASGV) on shoot proliferation of in vitro stock cultures and recovery of cryopreserved shoot tips of 'Gala' apple. Results showed that virus infection reduced shoot proliferation of in vitro stock cultures and cell ability to regenerate normal shoots in cryopreserved shoot tips. Virus infection increased total soluble protein, total soluble sugar and free proline levels and altered endogenous levels of indoleacetic acid (IAA) and zeatin riboside (ZR), but induced severe cell membrane damage and caused alternation in mitochondria shape of the in vitro stock shoots. The altered levels of IAA and ZR were most likely to be responsible for the reduced shoot proliferation of in vitro stock culture. Cell damage and alternations in mitochondria shape in ASGV-infected shoot tips were most likely responsible for the reduced cell ability to regenerate normal shoots following cryopreservation. To the best of our knowledge, this is the first study on effects of virus infection on recovery of cryopreserved shoot tips. Results reported here emphasize that healthy in vitro stock cultures should be used for cryopreservation.


Assuntos
Criopreservação/métodos , Malus/virologia , Doenças das Plantas/virologia , Brotos de Planta/crescimento & desenvolvimento , Brotos de Planta/virologia , Flexiviridae , Malus/crescimento & desenvolvimento
12.
Plant Dis ; 101(9): 1606-1615, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30677332

RESUMO

Reddish-purple coloration on the leaf blades and downward rolling of leaf margins are typical symptoms of grapevine leafroll disease (GLD) in red-fruited grapevine cultivars. These typical symptoms are attributed to the expression of genes encoding enzymes for anthocyanins synthesis, and the accumulation of flavonoids in diseased leaves. Drought has been proven to accelerate development of GLD symptoms in virus-infected leaves of grapevine. However, it is not known how drought affects GLD expression nor how anthocyanin biosynthesis in virus-infected leaves is altered. The present study used HPLC to determine the types and levels of anthocyanins, and applied reverse transcription quantitative polymerase chain reaction (RT-qPCR) to analyze the expression of genes encoding enzymes for anthocyanin synthesis. Plantlets of Grapevine leafroll-associated virus 3 (GLRaV-3)-infected Vitis vinifera 'Cabernet Sauvignon' were grown in vitro under PEG-induced drought stress. HPLC found no anthocyanin-related peaks in the healthy plantlets with or without PEG-induced stress, while 11 peaks were detected in the infected plantlets with or without PEG-induced drought stress, but the peaks were significantly higher in infected drought-stressed plantlets. Increased accumulation of total anthocyanin compounds was related to the development of GLD symptoms in the infected plantlets under PEG stress. The highest level of up-regulated gene expression was found in GLRaV-3-infected leaves with PEG-induced drought stress. Analyses of variance and correlation of anthocyanin accumulation with related gene expression levels found that GLRaV-3-infection was the key factor in increased anthocyanin accumulation. This accumulation involved the up-regulation of two key genes, MYBA1 and UFGT, and their expression levels were further enhanced by drought stress.


Assuntos
Antocianinas , Closteroviridae , Folhas de Planta , Regulação para Cima , Vitis , Antocianinas/genética , Closteroviridae/fisiologia , Secas , Folhas de Planta/virologia , Estresse Fisiológico/genética , Vitis/virologia
13.
Front Physiol ; 7: 203, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27313542

RESUMO

Stresses caused by viral diseases and drought have long threatened sustainable production of grapevine. These two stresses frequently occur simultaneously in many of grapevine growing regions of the world. We studied responses of in vitro-grown plantlets (Vitis vinifera) to Grapevine leafroll associated virus-3 (GLRaV-3) and PEG-induced drought stress. Results showed that stress induced by either virus infection or drought had negative effects on vegetative growth, caused significant decreases and increases in total soluble protein and free proline, respectively, induced obvious cell membrane damage and cell death, and markedly increased accumulations of [Formula: see text] and H2O2. Co-stress by virus and drought had much severer effects than single stress on the said parameters. Virus infection alone did not cause significant alternations in activities of POD, ROS, and SOD, and contents of MDA, which, however, markedly increased in the plantlets when grown under single drought stress and co-stress by the virus and drought. Levels of ABA increased, while those of IAA decreased in the plantlets stressed by virus infection or drought. Simultaneous stresses by the virus and drought had co-effects on the levels of ABA and IAA. Up-regulation of expressions of ABA biosynthesis genes and down-regulation of expressions of IAA biosynthesis genes were responsible for the alternations of ABA and IAA levels induced by either the virus infection or drought stress and co-stress by them. Experimental strategies established in the present study using in vitro system facilitate investigations on 'pure' biotic and abiotic stress on plants. The results obtained here provide new insights into adverse effects of stress induced by virus and drought, in single and particularly their combination, on plants, and allow us to re-orientate agricultural managements toward sustainable development of the agriculture.

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