Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 58
Filtrar
Mais filtros

Base de dados
País/Região como assunto
Tipo de documento
Intervalo de ano de publicação
1.
J Craniofac Surg ; 2024 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-38252540

RESUMO

When plastic surgeons reconstruct the defects for recurrent cancer, a longer vascular pedicle is often necessary because usable vessels are sacrificed in previous surgeries or radiotherapy. In this case, we would like to present another method for free anterolateral thigh flap pedicle elongation. A 59-year-old man was referred to our clinic for reconstruction after unilateral total maxillectomy and orbital exenteration due to recurrent squamous cell carcinoma. We need to cover the full-thickness defect in the left orbital area (8×7 cm sized), intraoral area (5×7 cm sized), and orbital floor. Due to prior surgeries and radiotherapy, we needed a vascular pedicle up to 15 cm for a distant recipient vessel. When harvesting the flap, we transected just proximal to the bifurcation site, harvested a muscular branch to vastus intermedius together, and used it for pedicle elongation by vessel turning over. A 17×6 cm sized musculocutaneous flap was harvested, and the total length of the pedicle was 15 cm. As the anastomosis was done at the distal portion of the vastus intermedius branch, there was no size mismatch with the superior thyroid artery. Both skin defects and the orbital floor were covered without any tension. The reconstruction was successful without any flap compromise 1 year after surgery. This case suggests another option for microsurgeons to lengthen the flap pedicle and reduce size mismatch using anatomical variability of the lateral circumflex femoral artery.

2.
Comput Inform Nurs ; 42(3): 226-239, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38300124

RESUMO

This study aimed to explore digital literacy among community-dwelling older adults in urban South Korea. A semistructured interview guide was developed using the Digital Competence ( 2.0 framework, which emphasizes the competencies for full digital participation in five categories: information and data literacy, communication and collaboration, content creation, safety, and problem-solving. The data were analyzed using combined inductive and deductive content analysis. Inductive analysis identified three main categories: perceived ability to use digital technology, responses to digital technology, and contextual factors. In the results of deductive analysis, participants reported varying abilities in using digital technologies for information and data literacy, communication or collaboration, and problem-solving. However, their abilities were limited in handling the safety or security of digital technology and lacked in creating digital content. Responses to digital technology contain subcategories of perception (positive or negative) and behavior (trying or avoidance). Regarding contextual factors, aging-related physical and cognitive changes were identified as barriers to digital literacy. The influence of families or peers was viewed as both a facilitator and a barrier. Our participants recognized the importance of using digital devices to keep up with the trend of digitalization, but their digital literacy was mostly limited to relatively simple levels.


Assuntos
Comunicação , Alfabetização , Humanos , Idoso , Pesquisa Qualitativa , Envelhecimento , República da Coreia
3.
Angew Chem Int Ed Engl ; 63(1): e202316264, 2024 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-37983973

RESUMO

The local confinement effect, which can generate a high concentration of hydroxide ions and reaction intermediates near the catalyst surface, is an important strategy for converting CO2 into multi-carbon products in electrocatalytic CO2 reduction. Therefore, understanding how the shape and dimension of the confinement geometry affect the product selectivity is crucial. In this study, we report for the first time the effect of the shape (degree of confinement) and dimension of the confined space on the product selectivity without changing the intrinsic property of Cu. We demonstrate that geometry influences the outcomes of products, such as CH4 , C2 H4 , and EtOH, in different ways: the selectivity of CH4 and EtOH is affected by shape, while the selectivity of C2 H4 is influenced by dimension of geometry predominantly. These phenomena are demonstrated, both experimentally and through simulation, to be induced by the local confinement effect within the confined structure. Our geometry model could serve as basis for designing the confined structures tailored for the production of specific products.

4.
J Med Internet Res ; 25: e51616, 2023 12 14.
Artigo em Inglês | MEDLINE | ID: mdl-38095999

RESUMO

BACKGROUND: The need for digital literacy in aging populations is increasing in the digitalizing society. Digital literacy involves the identification, evaluation, and communication of information through various digital devices or relevant programs. OBJECTIVE: The aims of this study were to develop an Everyday Digital Literacy Questionnaire (EDLQ), a digital literacy assessment scale, and subsequently evaluate its psychometric properties using a population of community-dwelling older adults in South Korea. METHODS: The EDLQ was developed using an instrument development design. A nationwide survey was conducted, and the study included 1016 community-dwelling older adults (age ≥60 years). To evaluate the psychometric properties, the participants were randomly divided into 2 groups (n=508 each), and the internal consistency (Cronbach α and McDonald ω), structural validity (exploratory factor analysis and confirmatory factor analysis), hypothesis-testing construct validity using the eHealth Literacy Scale (eHEALS), and measurement invariance were analyzed. RESULTS: Among the initial 30 items of the EDLQ, 22 items with a 3-factor solution had a total explained variance of 77%. The domains included "information and communication" (9 items), "content creation and management" (4 items), and "safety and security" (9 items). Confirmatory factor analysis was conducted with this 3-factor solution (χ2206=345.1; normed χ2206=1.7; comparative fit index=0.997; Tucker-Lewis index=0.997; root-mean-square error of approximation=0.036; standardized root-mean-square residual=0.050; composite reliability=0.903-0.959; average variance extracted=0.699-0.724; R2=0.616-0.773). Hypothesis-testing construct validity with the eHEALS revealed a strong correlation (r=0.75). Cronbach α and McDonald ω coefficients were .98 and 0.98, respectively. The fit indices for measurement invariance, including the configural, metric, and scalar invariance models, demonstrated a satisfactory fit to the data. Our findings suggest that the psychometric properties of the 22-item EDLQ are valid and reliable for assessing digital literacy among older Korean adults. CONCLUSIONS: In this study, we developed a digital literacy measure with strong psychometric properties that made it suitable for assessing the digital literacy of community-dwelling older adults in Korea. To broaden its applicability, however, further assessment of its feasibility for use with different languages and cultures is necessary. Moreover, more empirical research on digital literacy and related factors in older adults can facilitate the development of personalized digital health care services and educational interventions in the digital society.


Assuntos
Letramento em Saúde , Telemedicina , Humanos , Idoso , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Projetos de Pesquisa , Idioma , Inquéritos e Questionários , Psicometria
5.
Nano Lett ; 22(3): 1174-1182, 2022 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-35073103

RESUMO

The optimal architecture of three-dimensional (3D) interface between a polymer electrolyte membrane (PEM) and catalyst layer (CL) is one of the most important issues to improve PEM fuel cells' (PEMFCs) performance. Here, we report the fabrication of hierarchical wrinkled PEM/CL interface over a large area. We fabricated the hierarchical wrinkles on a multiscale from nanometers to micrometers by bottom-up-based facile, scalable, and simple method. Notably, it allows one to go beyond the limit of the catalyst utilization by extremely enlarged interfacial area. The resulting hierarchical wrinkled PEM/CL displays a dramatically increased electrochemically active surface area (ECSA) and power performance by the enhancement factors of 89% and 67% compared with those of flat interface, which is one of the best enhancements compared to previous PEMFCs. We believe the scalability of hierarchical wrinkled interface can be exploited to design advanced 3D interfaces for high-performance PEMFCs even with ultralow Pt-loading.

6.
Small ; 18(17): e2106648, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35297560

RESUMO

Although the dendritic cell (DC)-based modulation of immune responses has emerged as a promising therapeutic strategy for tumors, infections, and autoimmune diseases, basic research and therapeutic applications of DCs are hampered by expensive growth factors and sophisticated culture procedures. Furthermore, the platform to drive the differentiation of a certain DC subset without any additional biochemical manipulations has not yet been developed. Here, five types of polymer films with different hydrophobicity via an initiated chemical vapor deposition (iCVD) process to modulate the interactions related to cell-substrate adhesion are introduced. Especially, poly(cyclohexyl methacrylate) (pCHMA) substantially enhances the expansion and differentiation of conventional type 1 DCs (cDC1s), the prime DC subset for antigen cross-presentation, and CD8+ T cell activation, by 4.8-fold compared to the conventional protocol. The cDC1s generated from the pCHMA-coated plates retain the bona fide DC functions including the expression of co-stimulatory molecules, cytokine secretion, antigen uptake and processing, T cell activation, and induction of antitumor immune responses. To the authors' knowledge, this is the first report highlighting that the modulation of surface hydrophobicity of the culture plate can be an incisive approach to construct an advanced DC culture platform with high efficiency, which potentially facilitates basic research and the development of immunotherapy employing DCs.


Assuntos
Células Dendríticas , Polímeros , Apresentação de Antígeno , Técnicas de Cultura de Células/métodos , Células Dendríticas/metabolismo , Ativação Linfocitária , Polímeros/metabolismo
7.
J Med Internet Res ; 24(9): e37753, 2022 09 06.
Artigo em Inglês | MEDLINE | ID: mdl-36066964

RESUMO

BACKGROUND: Depression is a severe psychological concern that negatively affects health in older adults. Serious games applied in various fields are considered appropriate interventions, especially in mental health care. However, there is a lack of evidence regarding the effects of serious games on depression in older adults. OBJECTIVE: This study aimed to investigate the characteristics and effectiveness of serious games for depression in older adults. METHODS: A systematic review and meta-analysis of randomized controlled trials were conducted. In total, 5 electronic databases (PubMed, CINAHL, Embase, PsycINFO, and Cochrane Library) were searched to identify relevant studies published until July 6, 2021. A total of 2 reviewers independently conducted study selection, data extraction, and quality appraisals. The risk of bias in the included studies was assessed using the JBI Critical Appraisal Checklist. For the meta-analysis, the effect size was calculated as the standardized mean difference (SMD) by using a random effects model. RESULTS: A total of 17 studies with 1280 older adults were included in the systematic review, and 15 studies were included in the meta-analysis. Serious game interventions were classified into 3 types: physical activity (PA), cognitive function, and both PA and cognitive function. The meta-analysis demonstrated that serious games reduced depression in older adults (SMD -0.54, 95% CI -0.79 to -0.29; P<.001). Serious games had a more significant effect size in community or home settings (SMD -0.61, 95% CI -0.95 to -0.26; P<.001) than in hospital settings (SMD -0.46, 95% CI -0.85 to -0.08; P=.02); however, the difference between groups was not significant. Among the types of games, games for PA (SMD -0.60, 95% CI -0.95 to -0.25; P<.001) and games for both (SMD -0.73, 95% CI -1.29 to -0.17; P=.01) had a significant effect on reducing depression in older adults. However, no significant correlations were observed between the duration or number of serious games and depression. CONCLUSIONS: Serious games were beneficial in reducing depression in older adults. Regardless of the study setting, serious games appeared to reduce depression. Particularly, serious games including PA had a significant impact on reducing depression. Furthermore, high-quality randomized controlled trials are needed to establish substantial evidence for the effectiveness of serious games on depression in older adults. TRIAL REGISTRATION: PROSPERO CRD42021242573; https://tinyurl.com/26xf7ym5.


Assuntos
Depressão , Exercício Físico , Idoso , Cognição , Depressão/terapia , Humanos , Ensaios Clínicos Controlados Aleatórios como Assunto
8.
BMC Med Inform Decis Mak ; 22(1): 206, 2022 08 02.
Artigo em Inglês | MEDLINE | ID: mdl-35918702

RESUMO

BACKGROUND: Peripheral artery disease (PAD) is a cardiovascular disease that can be improved by risk factor modification. Mobile health (mHealth) intervention is an effective method of healthcare delivery to promote behavior changes. An mHealth platform can encourage consistent involvement of participants and healthcare providers for health promotion. This study aimed to develop an mHealth platform consisting of a smartphone application (app) synchronized with a wearable activity tracker and a web-based portal to support exercise intervention in patients with PAD. METHODS: This study was conducted based on an iterative development process, including analysis, design, and implementation. In the analysis phase, a literature review and needs assessment through semi-structured interviews (n = 15) and a questionnaire-based survey (n = 138) were performed. The initial prototype design and contents were developed based on the users' requirements. In the implementation phase, multidisciplinary experts (n = 4) evaluated the heuristics, following which the mHealth platform was revised. User evaluation of the usability was performed by nurses (n = 4) and patients with PAD (n = 3). RESULTS: Through the development process, the functional requirements of the platform were represented through visual display, reminder, education, self-monitoring, goal setting, goal attainment, feedback, and recording. In-app videos of exercise and PAD management were produced to provide information and in-app automatic text messages were developed for user motivation. The final version of the platform was rated 67.86 out of 100, which indicated "good" usability. CONCLUSIONS: The mHealth platform was designed and developed for patients with PAD and their healthcare providers. This platform can be used to educate and promote individualized exercise among patients with PAD.


Assuntos
Aplicativos Móveis , Doença Arterial Periférica , Telemedicina , Exercício Físico , Humanos , Doença Arterial Periférica/terapia , Telemedicina/métodos , Design Centrado no Usuário
9.
Microsurgery ; 41(8): 734-742, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34636068

RESUMO

BACKGROUND: With severe vascular calcifications, vascular clamp application and utilizing the vessel for free flap recipient vessel becomes impossible. These obstacles can be overcome with the Fogarty catheter and vein graft. PATIENTS AND METHODS: When unclampable artery was encountered intraoperatively, a vein graft was used to make a clampable recipient site for six diabetic foot patients (ages from 42 to 80). The end of the Fogarty catheter was inserted into the proximal end of the vein graft and the transected calcified vessel in sequence, and the balloon of the catheter was used as an intraluminal tourniquet. The remaining end of the vein graft was connected to the distal vessel with a vascular clamp. RESULTS: Five short vein graft revascularization for segmental arterial occlusion, one long vein graft for recipient artery elongation was done (lengths from 2 to 13.8 cm). Three delayed, and two immediate anterolateral thigh flaps (sizes from 15 to 150 cm2 ) were performed, and one patient received vein graft revascularization surgery only. Postoperative vascular sonography of all six patients showed well-maintained patency. Minor flap marginal disruption occurred at two patients but healed with conservative care. Postoperative follow-up was done for 1-18 months (average 7.17). Limb salvage was achieved for five patients and all five free flaps survived. However, for one patient, arterial restenosis at popliteal artery a month later lead to major amputation. CONCLUSION: Using a Fogarty catheter and a vein graft may obtain perfect hemostasis during micro-anastomosis and achieve successful microvascular reconstruction in patients with severely calcified vessels.


Assuntos
Retalhos de Tecido Biológico , Salvamento de Membro , Catéteres , Humanos , Extremidade Inferior/cirurgia , Artéria Poplítea/cirurgia , Estudos Retrospectivos , Resultado do Tratamento , Grau de Desobstrução Vascular
10.
Biotechnol Bioprocess Eng ; 26(2): 165-178, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33821132

RESUMO

For last two decades, the demand for precisely engineered three-dimensional structures has increased continuously for the developments of biomaterials. With the recent advances in micro- and nano-fabrication techniques, various devices with complex surface geometries have been devised and produced in the pharmaceutical and medical fields for various biomedical applications including drug delivery and biosensors. These advanced biomaterials have been designed to mimic the natural environments of tissues more closely and to enhance the performance for their corresponding biomedical applications. One of the important aspects in the rational design of biomaterials is how to configure the surface of the biomedical devices for better control of the chemical and physical properties of the bioactive surfaces without compromising their bulk characteristics. In this viewpoint, it of critical importance to secure a versatile method to modify the surface of various biomedical devices. Recently, a vapor phase method, termed initiated chemical vapor deposition (iCVD) has emerged as damage-free method highly beneficial for the conformal deposition of various functional polymer films onto many kinds of micro- and nano-structured surfaces without restrictions on the substrate material or geometry, which is not trivial to achieve by conventional solution-based surface functionalization methods. With proper structural design, the functional polymer thin film via iCVD can impart required functionality to the biomaterial surfaces while maintaining the fine structure thereon. We believe the iCVD technique can be not only a valuable approach towards fundamental cell-material studies, but also of great importance as a platform technology to extend to other prospective biomaterial designs and material interface modifications for biomedical applications.

11.
Plant Cell ; 27(6): 1771-87, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26059204

RESUMO

Drought and other abiotic stresses negatively affect plant growth and development and thus reduce productivity. The plant-specific NAM/ATAF1/2/CUC2 (NAC) transcription factors have important roles in abiotic stress-responsive signaling. Here, we show that Arabidopsis thaliana NAC016 is involved in drought stress responses; nac016 mutants have high drought tolerance, and NAC016-overexpressing (NAC016-OX) plants have low drought tolerance. Using genome-wide gene expression microarray analysis and MEME motif searches, we identified the NAC016-specific binding motif (NAC16BM), GATTGGAT[AT]CA, in the promoters of genes downregulated in nac016-1 mutants. The NAC16BM sequence does not contain the core NAC binding motif CACG (or its reverse complement CGTG). NAC016 directly binds to the NAC16BM in the promoter of ABSCISIC ACID-RESPONSIVE ELEMENT BINDING PROTEIN1 (AREB1), which encodes a central transcription factor in the stress-responsive abscisic acid signaling pathway and represses AREB1 transcription. We found that knockout mutants of the NAC016 target gene NAC-LIKE, ACTIVATED BY AP3/PI (NAP) also exhibited strong drought tolerance; moreover, NAP binds to the AREB1 promoter and suppresses AREB1 transcription. Taking these results together, we propose that a trifurcate feed-forward pathway involving NAC016, NAP, and AREB1 functions in the drought stress response, in addition to affecting leaf senescence in Arabidopsis.


Assuntos
Proteínas de Arabidopsis/fisiologia , Arabidopsis/fisiologia , Fatores de Transcrição de Zíper de Leucina Básica/fisiologia , Regulação da Expressão Gênica de Plantas/fisiologia , Fatores de Transcrição/fisiologia , Envelhecimento/fisiologia , Proteínas de Arabidopsis/biossíntese , Fatores de Transcrição de Zíper de Leucina Básica/biossíntese , Desidratação/fisiopatologia , Regulação para Baixo , Técnicas de Inativação de Genes , Folhas de Planta/fisiologia , Transdução de Sinais/fisiologia
12.
Molecules ; 21(7)2016 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-27376259

RESUMO

Two new feruloyl amides, N-cis-hibiscusamide (5) and (7'S)-N-cis-feruloylnormetanephrine (9), and eight known feruloyl amides were isolated from Portulaca oleracea L. and the geometric conversion of the ten isolated feruloyl amides by UV light was verified. The structures of the feruloyl amides were determined based on spectroscopic data and comparison with literature data. The NMR data revealed that the structures of the isolated compounds showed cis/trans-isomerization under normal laboratory light conditions. Therefore, cis and trans-isomers of feruloyl amides were evaluated for their convertibility and stability by UV light of a wavelength of 254 nm. After 96 h of UV light exposure, 23.2%-35.0% of the cis and trans-isomers were converted to trans-isomers. Long-term stability tests did not show any significant changes. Among all compounds and conversion mixtures collected, compound 6 exhibited the strongest inhibition of IL-6-induced STAT3 activation in Hep3B cells, with an IC50 value of 0.2 µM. This study is the first verification of the conversion rates and an equilibrium ratio of feruloyl amides. These results indicate that this natural material might provide useful information for the treatment of various diseases involving IL-6 and STAT3.


Assuntos
Amidas/química , Amidas/farmacologia , Interleucina-6/metabolismo , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Portulaca/química , Fator de Transcrição STAT3/metabolismo , Linhagem Celular Tumoral , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Humanos , Interleucina-6/farmacologia , Janus Quinase 2/metabolismo , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Fosforilação/efeitos dos fármacos
13.
Plant Cell Physiol ; 56(12): 2325-39, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26443376

RESUMO

NAM/ATAF1/ATAF2/CUC2 (NAC) is a plant-specific transcription factor (TF) family, and NACs participate in many diverse processes during the plant life cycle. Several Arabidopsis thaliana NACs have important roles in positively or negatively regulating leaf senescence, but in other plant species, including rice, the senescence-associated NACs (senNACs) remain largely unknown. Here we show that the rice senNAC TF ONAC106 negatively regulates leaf senescence. Leaves of onac106-1D (insertion of the 35S enhancer in the promoter region of the ONAC106 gene) mutants retained their green color under natural senescence and dark-induced senescence conditions. Genome-wide transcriptome analysis revealed that key senescence-associated genes (SGR, NYC1, OsNAC5, OsNAP, OsEIN3 and OsS3H) were differentially expressed in onac106-1D during dark-induced senescence. In addition to delayed senescence, onac106-1D also showed a salt stress-tolerant phenotype; key genes that down-regulate salt response signaling (OsNAC5, OsDREB2A, OsLEA3 and OsbZIP23) were rapidly up-regulated in onac106-1D under salt stress. Interestingly, onac106-1D also exhibited a wide tiller angle phenotype throughout development, and the tiller angle-related gene LPA1 was down-regulated in onac106-1D. Using yeast one-hybrid assays, we found that ONAC106 binds to the promoter regions of SGR, NYC1, OsNAC5 and LPA1. Taking these results together, we propose that ONAC106 functions in leaf senescence, salt stress tolerance and plant architecture by modulating the expression of its target genes that function in each signaling pathway.


Assuntos
Oryza/fisiologia , Folhas de Planta/crescimento & desenvolvimento , Proteínas de Plantas/metabolismo , Brotos de Planta/anatomia & histologia , Tolerância ao Sal , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Genes de Plantas , Oryza/efeitos dos fármacos , Oryza/genética , Fenótipo , Folhas de Planta/efeitos dos fármacos , Folhas de Planta/genética , Proteínas de Plantas/genética , Brotos de Planta/efeitos dos fármacos , Regiões Promotoras Genéticas/genética , Tolerância ao Sal/efeitos dos fármacos , Tolerância ao Sal/genética , Cloreto de Sódio/farmacologia , Estresse Fisiológico/efeitos dos fármacos , Estresse Fisiológico/genética , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
14.
Plant J ; 74(1): 122-33, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23289852

RESUMO

NADPH:protochlorophyllide oxidoreductase (POR) catalyzes photoreduction of protochlorophyllide (Pchlide) to chlorophyllide in chlorophyll (Chl) synthesis, and is required for prolamellar body (PLB) formation in etioplasts. Rice faded green leaf (fgl) mutants develop yellow/white leaf variegation and necrotic lesions during leaf elongation in field-grown plants. Map-based cloning revealed that FGL encodes OsPORB, one of two rice POR isoforms. In fgl, etiolated seedlings contained smaller PLBs in etioplasts, and lower levels of total and photoactive Pchlide. Under constant or high light (HL) conditions, newly emerging green leaves rapidly turned yellow and formed lesions. Increased levels of non-photoactive Pchlide, which acts as a photosensitizer, may cause reactive oxygen accumulation and lesion formation. OsPORA expression is repressed by light and OsPORB expression is regulated in a circadian rhythm in short-day conditions. OsPORA was expressed at high levels in developing leaves and decreased dramatically in fully mature leaves, whereas OsPORB expression was relatively constant throughout leaf development, similar to expression patterns of AtPORA and AtPORB in Arabidopsis. However, OsPORB expression is rapidly upregulated by HL treatment, similar to the fluence rate-dependent regulation of AtPORC. This suggests that OsPORB function is equivalent to both AtPORB and AtPORC functions. Our results demonstrate that OsPORB is essential for maintaining light-dependent Chl synthesis throughout leaf development, especially under HL conditions, whereas OsPORA mainly functions in the early stages of leaf development. Developmentally and physiologically distinct roles of monocot OsPORs are discussed by comparing with those of dicot AtPORs.


Assuntos
Clorofila/biossíntese , Luz , Oryza/enzimologia , Oxirredutases atuantes sobre Doadores de Grupo CH-CH/metabolismo , Proteínas de Plantas/metabolismo , Clonagem Molecular , Mutação da Fase de Leitura , Regulação da Expressão Gênica de Plantas , Oryza/genética , Oryza/efeitos da radiação , Oxirredutases atuantes sobre Doadores de Grupo CH-CH/genética , Folhas de Planta/enzimologia , Folhas de Planta/efeitos da radiação , Proteínas de Plantas/genética , Deleção de Sequência
15.
J Exp Bot ; 65(14): 3915-25, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24510943

RESUMO

Plant autophagy, one of the essential proteolysis systems, balances proteome and nutrient levels in cells of the whole plant. Autophagy has been studied by analysing Arabidopsis thaliana autophagy-defective atg mutants, but the relationship between autophagy and chlorophyll (Chl) breakdown during stress-induced leaf yellowing remains unclear. During natural senescence or under abiotic-stress conditions, extensive cell death and early yellowing occurs in the leaves of atg mutants. A new finding is revealed that atg5 and atg7 mutants exhibit a functional stay-green phenotype under mild abiotic-stress conditions, but leaf yellowing proceeds normally in wild-type leaves under these conditions. Under mild salt stress, atg5 leaves retained high levels of Chls and all photosystem proteins and maintained a normal chloroplast structure. Furthermore, a double mutant of atg5 and non-functional stay-green nonyellowing1-1 (atg5 nye1-1) showed a much stronger stay-green phenotype than either single mutant. Taking these results together, it is proposed that autophagy functions in the non-selective catabolism of Chls and photosynthetic proteins during stress-induced leaf yellowing, in addition to the selective degradation of Chl-apoprotein complexes in the chloroplasts through the senescence-induced STAY-GREEN1/NYE1 and Chl catabolic enzymes.


Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/citologia , Autofagia , Clorofila/metabolismo , Mutação/genética , Fotossíntese , Pigmentação , Folhas de Planta/fisiologia , Arabidopsis/efeitos dos fármacos , Arabidopsis/genética , Arabidopsis/fisiologia , Proteínas de Arabidopsis/genética , Autofagia/efeitos dos fármacos , Autofagia/genética , Proteína 5 Relacionada à Autofagia , Cloroplastos/efeitos dos fármacos , Cloroplastos/metabolismo , Cloroplastos/ultraestrutura , Escuridão , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Genes de Plantas , Complexos de Proteínas Captadores de Luz/metabolismo , Fenótipo , Monoéster Fosfórico Hidrolases/metabolismo , Fotossíntese/efeitos dos fármacos , Pigmentação/efeitos dos fármacos , Folhas de Planta/efeitos dos fármacos , Cloreto de Sódio/farmacologia , Estresse Fisiológico/efeitos dos fármacos , Estresse Fisiológico/genética
16.
Heliyon ; 10(3): e25600, 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-38333821

RESUMO

Ecklonia cava is a nutrient-rich algae species that contains abundant physiological phytochemicals, including peptides, carotenoids, fucoidans, and phlorotannins. However, elucidation of the antiviral effects of this algae and identification of new functional ingredients warrant further investigation. This study was aimed at investigating the potential anti-hepatitis A virus activities of extracts of E. cava prepared in different solvents. E. cava extracts were prepared using hot water and 70 % ethanol. The antioxidant activities of the extracts were confirmed by analyzing the total phenolic content, as well as 2,2-diphenyl-1-picrylhydrazyl and 2,2'-azino-bis-3-ethylbenzothiazoline-6-sulfonic acid radical scavenging activities. The inhibitory effects of the extracts against hepatitis A virus were analyzed using real-time polymerase chain reaction. The E. cava extract yield was 22.5-27.2 % depending on the extraction solvent. The 2,2-diphenyl-1-picrylhydrazyl radical scavenging activity was 70.44 % and 91.05 % for hot water and ethanol extracts at a concentration of 1000 ppm. The 2,2'-azino-bis-3-ethylbenzothiazoline-6-sulfonic acid radical scavenging activity of the ethanol extract was the highest (93.57 %) at 1000 µg/mL. Fourier-transform infrared was used to identify the functional groups (phlorotannin and alginate) in the extraction solvents. Ultra-high performance liquid chromatography with quadrupole time-of-flight tandem mass spectrometry analysis revealed a potential bioactive compound previously unidentified in E. cava. Finally, we identified the antiviral activity of E. cava extracts against hepatitis A virus replication. These findings demonstrate that E. cava could be used as an anti-hepatitis A virus functional food and biological material.

17.
ACS Nano ; 2024 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-38315048

RESUMO

Developing a superomniphobic surface that exceeds the static and dynamic repellency observed in nature's springtails for various liquids presents a significant challenge in the realm of surface and interface science. However, progress in this field has been particularly limited when dealing with low-surface-tension liquids. This is because dynamic repellency values are typically at least 2 orders of magnitude lower than those observed with water droplets. Our study introduces an innovative hierarchical topography demonstrating exceptional dynamic repellency to low-surface-tension liquids. Inspired by the structural advantages found in springtails, we achieve a static contact angle of >160° and the complete rebound of droplet impact with a Weber number (We) of ∼104 using ethanol. These results surpass all existing benchmarks that have been reported thus far, including those of natural surfaces. The key insight from our research is the vital role of the microscale air pocket size, governed by wrinkle wavelength, in both static and dynamic repellency. Additionally, nanoscale air pockets within serif-T nanostructures prove to be essential for achieving omniphobicity. Our investigations into the wetting dynamics of ethanol droplets further reveal aspects such as the reduction in contact time and the occurrence of a fragmentation phenomenon beyond We ∼ 350, which has not been previously observed.

18.
Adv Healthc Mater ; : e2400170, 2024 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-38989721

RESUMO

Chronic wounds adversely affect the quality of life. Although electrical stimulation has been utilized to treat chronic wounds, there are still limitations to practicing it due to the complicated power system. Herein, an electrostimulating membrane incorporated with electrospun nanofiber (M-sheet) to treat diabetic wounds is developed. Through the screen printing method, the various alternate patterns of both Zn and AgCl on a polyurethane substrate, generating redox-mediated electrical fields are introduced. The antibacterial ability of the patterned membrane against both E. coli and S. aureus is confirmed. Furthermore, the poly(vinyl alcohol) (PVA)/gelatin electrospun fiber is incorporated into the patterned membrane to enhance biocompatibility and maintain the wet condition in the wound environment. The M-sheet can improve cell proliferation and migration in vitro and has an immune regulatory effect by inducing the polarization of macrophage to the M2 phenotype. Finally, when applied to a diabetic skin wound model, the M-sheet displays an accelerated wound healing rate and enhances re-epithelialization, collagen synthesis, and angiogenesis. It suggests that the M-sheet is a simple and portable system for the spontaneous generation of electrical stimulation and has great potential to be used in the practical wound and other tissue engineering applications.

19.
Cancers (Basel) ; 16(9)2024 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-38730618

RESUMO

Dysregulated DNA methylation in cancer is critical in the transcription machinery associated with cancer progression. Triple-negative breast cancer (TNBC) is the most aggressive breast cancer subtype, but no treatment targeting TNBC biomarkers has yet been developed. To identify specific DNA methylation patterns in TNBC, methyl-binding domain protein 2 (MBD) sequencing data were compared in TNBC and the three other major breast cancer subtypes. Integrated analysis of DNA methylation and gene expression identified a gene set showing a correlation between DNA methylation and gene expression. ATPase Na+/K+-transporting subunit alpha 1 (ATP1A1) was found to be specifically hypomethylated in the coding sequence (CDS) region and to show increased expression in TNBC. The Cancer Genome Atlas (TCGA) database also showed that hypomethylation and high expression of ATP1A1 were strongly associated with poor survival in patients with TNBC. Furthermore, ATP1A1 knockdown significantly reduced the viability and tumor-sphere formation of TNBC cells. These results suggest that the hypomethylation and overexpression of ATP1A1 could be a prognostic marker in TNBC and that the manipulation of ATP1A1 expression could be a therapeutic target in this disease.

20.
Plant Cell Physiol ; 54(10): 1660-72, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23926065

RESUMO

The highly ordered process of senescence forms the final stage of leaf development; a large set of senescence-associated genes (SAGs) execute this orderly dismantling of the photosynthetic apparatus and remobilization of cellular components. A number of transcription factors (TFs) modulate SAG expression to promote or delay senescence. Here we show that NAC016, the previously uncharacterized senescence-associated NAM/ATAF1/2/CUC2 (senNAC) TF in Arabidopsis thaliana, promotes senescence. Leaves of nac016 mutants remained green under senescence-inducing conditions, and leaves of NAC016-overexpressing (NAC016-OX) plants senesced early. Under dark-induced senescence (DIS) conditions, nac016 mutants had low ion leakage, and retained the proper balance of photosystem proteins and normal grana thylakoid shape much longer than wild-type plants, suggesting that nac016 acts as a functional stay-green type senescence mutant. Under DIS conditions, SAGs (NYC1, PPH, SGR1/NYE1 and WRKY22), including senNACs (JUB1, NAP, ORE1, ORS1 and VNI2), were down-regulated in nac016 mutants and up-regulated in NAC016-OX plants. In addition to its role in senescence, NAC016 also affects abiotic stress. Under salt and oxidative stress conditions, NAC016 expression rapidly increased in developing leaves, possibly to promote senescence. Indeed, under the stress conditions, nac016 mutants stayed green and NAC016-OX plants senesced rapidly. To identify direct targets of the NAC016 TF in the regulation of leaf senescence, we conducted yeast one-hybrid assays, which strongly suggested that NAC016 binds to the promoters of NAP and ORS1. Based on these results, we propose that NAC016 regulatory mechanisms promoting leaf senescence exhibit cross-talk with the salt and oxidative stress-responsive signaling pathways.


Assuntos
Proteínas de Arabidopsis/genética , Arabidopsis/genética , Mutação , Folhas de Planta/genética , Sequência de Aminoácidos , Arabidopsis/metabolismo , Arabidopsis/fisiologia , Proteínas de Arabidopsis/classificação , Proteínas de Arabidopsis/metabolismo , Escuridão , Regulação da Expressão Gênica no Desenvolvimento , Regulação da Expressão Gênica de Plantas , Peróxido de Hidrogênio/farmacologia , Immunoblotting , Microscopia Eletrônica de Transmissão , Dados de Sequência Molecular , Oxidantes/farmacologia , Filogenia , Reguladores de Crescimento de Plantas/farmacologia , Folhas de Planta/metabolismo , Folhas de Planta/fisiologia , Plantas Geneticamente Modificadas , Ligação Proteica , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Homologia de Sequência de Aminoácidos , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/genética , Transdução de Sinais/efeitos da radiação , Cloreto de Sódio/farmacologia , Tilacoides/efeitos dos fármacos , Tilacoides/efeitos da radiação , Tilacoides/ultraestrutura , Fatores de Transcrição/classificação , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Técnicas do Sistema de Duplo-Híbrido
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA