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1.
J Rural Med ; 19(2): 83-91, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38655231

RESUMO

Objective: To clarify the association between dementia knowledge and attitudes, lifestyle backgrounds, and practical training experiences of nursing students, and examine the basic nursing education for dementia. Participants and Methods: A total of 412 first-to-fourth-year students at Nursing College A participated in the study. A cross-sectional survey was conducted regarding knowledge (15 questions) and attitudes (15 questions) related to dementia. Results: Consent was obtained from 158 individuals (The response rate was 38.3%). Significant items regarding dementia attitudes and cohabitation experiences were identified. Additionally, significant items regarding attitude toward dementia and care providing experiences were identified. Conclusion: Associations among attitude toward dementia, cohabitation experiences, and care providing experiences were determined. Knowledge and attitudes regarding dementia improved with practical training experience.

2.
J Phys Chem B ; 128(3): 744-754, 2024 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-38204413

RESUMO

The creation of unidirectional ion transporters across membranes represents one of the greatest challenges in chemistry. Proton-pumping rhodopsins are composed of seven transmembrane helices with a retinal chromophore bound to a lysine side chain via a Schiff base linkage and provide valuable insights for designing such transporters. What makes these transporters particularly intriguing is the discovery of both outward and inward proton-pumping rhodopsins. Surprisingly, despite sharing identical overall structures and membrane topologies, these proteins facilitate proton transport in opposite directions, implying an underlying rational mechanism that can transport protons in different directions within similar protein structures. In this study, we unraveled this mechanism by examining the chromophore structures of deprotonated intermediates in schizorhodopsins, a recently discovered subfamily of inward proton-pumping rhodopsins, using time-resolved resonance Raman spectroscopy. The photocycle of schizorhodopsins revealed the cis-trans thermal isomerization that precedes reprotonation at the Schiff base of the retinal chromophore. Notably, this order has not been observed in other proton-pumping rhodopsins, but here, it was observed in all seven schizorhodopsins studied across the archaeal domain, strongly suggesting that cis-trans thermal isomerization preceding reprotonation is a universal feature of the schizorhodopsin family. Based on these findings, we propose a structural basis for the remarkable order of events crucial for facilitating inward proton transport. The mechanism underlying inward proton transport by schizorhodopsins is straightforward and rational. The insights obtained from this study hold great promise for the design of transmembrane unidirectional ion transporters.


Assuntos
Bacteriorodopsinas , Bombas de Próton , Bombas de Próton/química , Prótons , Bacteriorodopsinas/química , Bases de Schiff/química , Transporte de Íons , Luz
3.
Angew Chem Int Ed Engl ; 61(33): e202203149, 2022 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-35749139

RESUMO

Recent discoveries of light-driven inward proton-pumping rhodopsins have opened new avenues to exploring the mechanism of unidirectional transport because these proteins transport protons in the opposite direction to conventional proton-pumping rhodopsins, despite their similar protein structure and membrane topology. Schizorhodopsin (SzR) is a newly discovered rhodopsin family of light-driven inward proton pumps. Here, we report time-resolved resonance Raman spectra showing that cis-trans thermal reisomerization precedes reprotonation at the Schiff base of the retinal chromophore in the photocycle of SzR AM_5_00977. This sequence has not been observed for the photocycles of conventional proton-pumping rhodopsins, in which reisomerization follows reprotonation, and thus provides insights into the mechanism of proton uptake to the chromophore during inward proton pumping. The present findings are expected to contribute to controlling the direction of proton transport in engineered proteins.


Assuntos
Bombas de Próton , Prótons , Transporte de Íons , Bombas de Próton/química , Rodopsina/química , Bases de Schiff
4.
Biochem Biophys Res Commun ; 477(4): 814-819, 2016 09 02.
Artigo em Inglês | MEDLINE | ID: mdl-27369076

RESUMO

The mouse submandibular gland (SMG) is important organ for embryonic development, and branching morphogenesis is regulated by many molecules containing transcription factors. Real-time reverse transcriptase polymerase chain reaction revealed that the expression of Brachyury increased in the SMG and peaked between E12.5-E13.5, concomitant with the early stage of branching morphogenesis. The expression of Brachyury in SMG rudiments between E12.5-E13.5 was confirmed by western blotting. In addition, fibronectin and Btbd7 (regulated by fibronectin), which are both essential for cleft formation, were expressed strongly during the same period. The Sox2 and Wnt3a, which regulate cell growth, were also expressed strongly during E12.5-E13.5. On the other hand, cleft formation and branching morphogenesis was suppressed by knockdown of Brachyury gene, suggesting that Brachyury plays a central role in regulating cell growth and cleft formation in early-stage embryonic mouse salivary gland development.


Assuntos
Proteínas Fetais/metabolismo , Regulação da Expressão Gênica no Desenvolvimento/fisiologia , Morfogênese/fisiologia , Fatores de Transcrição SOXB1/metabolismo , Glândulas Salivares/embriologia , Glândulas Salivares/metabolismo , Proteínas com Domínio T/metabolismo , Proteínas Adaptadoras de Transdução de Sinal , Animais , Fibronectinas/metabolismo , Camundongos , Camundongos Endogâmicos ICR , Proteínas Nucleares/metabolismo , Glândulas Salivares/citologia , Distribuição Tecidual
5.
J Biol Chem ; 287(21): 17493-17502, 2012 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-22451653

RESUMO

Osteoclasts are multinucleated giant cells that reside in osseous tissues and resorb bone. Signaling mediated by receptor activator of nuclear factor (NF)-κB (RANK) and its ligand leads to the nuclear factor of activated T cells 2/c1 (NFAT2 or NFATc1) expression, a critical step in the formation of functional osteoclasts. In addition, adaptor proteins harboring immunoreceptor tyrosine-based activation motifs, such as DNAX-activating protein of 12 kDa (DAP12), play essential roles. In this study, we identified the gene encoding the lectin Siglec-15 as NFAT2-inducible, and we found that the protein product links RANK ligand-RANK-NFAT2 and DAP12 signaling in mouse osteoclasts. Both the recognition of sialylated glycans by the Siglec-15 V-set domain and the association with DAP12 through its Lys-272 are essential for its function. When Siglec-15 expression was knocked down, fewer multinucleated cells developed, and those that did were morphologically contracted with disordered actin-ring structures. These changes were accompanied by significantly reduced bone resorption. Siglec-15 formed complexes with Syk through DAP12 in response to vitronectin. Furthermore, chimeric molecules consisting of the extracellular and transmembrane regions of Siglec-15 with a K272A mutation and the cytoplasmic region of DAP12 significantly restored bone resorption in cells with knocked down Siglec-15 expression. Together, these results suggested that the Siglec-15-DAP12-Syk-signaling cascade plays a critical role in functional osteoclast formation.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/biossíntese , Glicoproteínas de Membrana/biossíntese , Osteoclastos/metabolismo , Receptores Imunológicos/biossíntese , Transdução de Sinais/fisiologia , Proteínas Adaptadoras de Transdução de Sinal/genética , Animais , Reabsorção Óssea/genética , Reabsorção Óssea/metabolismo , Células CHO , Cricetinae , Cricetulus , Regulação da Expressão Gênica/fisiologia , Glicoproteínas de Membrana/genética , Camundongos , Mutação de Sentido Incorreto , Fatores de Transcrição NFATC/genética , Fatores de Transcrição NFATC/metabolismo , Células NIH 3T3 , Osteoclastos/citologia , Estrutura Terciária de Proteína , Ligante RANK/genética , Ligante RANK/metabolismo , Receptor Ativador de Fator Nuclear kappa-B/genética , Receptor Ativador de Fator Nuclear kappa-B/metabolismo , Receptores Imunológicos/genética , Lectina 1 Semelhante a Ig de Ligação ao Ácido Siálico
6.
Blood Cells Mol Dis ; 40(3): 410-3, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18201916

RESUMO

The complement system is an ancient cascade system that has a major role in innate and adaptive immunity. Component C3 is central to the three complement pathways. Hereditary compliment 3 (C3) deficiency characterized by severe recurrent infections and immune complex disorders is extremely rare disease. Since 1972, inherited C3 deficiency has been described in many families representing a variety of national origins; however, only 8 families of these cases have been identified their genetic defects. Interestingly, all except one (incomplete analysis) were shown to harbor homozygous C3 gene mutations. Previously we proposed a hypothesis, based on the unique process of C3 synthesis; C3 deficiency is not inherited as a simple autosomal recessive trait. Here, we report the first confirmed case with C3 deficiency caused by compound heterozygous mutations. They were a novel one base insertion (3176insT) in exon 24 which is predicted to result in a frameshift and a premature downstream stop codon (K1105X) in exon 26, and a nonsense mutation of C3303G (Y1081X) in exon 26 which was previously reported as homozygous mutations. This confirmed case suggests that our proposed hypothesis has prospects of a new aspect of pathogenesis for C3 deficiency.


Assuntos
Complemento C3/deficiência , Complemento C3/genética , Mutação , Pré-Escolar , Complemento C3/metabolismo , Éxons/genética , Heterozigoto , Homozigoto , Humanos , Masculino
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