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1.
J Phys Ther Sci ; 35(10): 696-702, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37791001

RESUMO

[Purpose] The deterioration in the psychological states of healthcare workers may impact the quality and quantity of medical care provided to patients, leading to unfavorable treatment outcomes. Thus, we aimed to investigate the relationship between reasons for employment and the mental health status of rehabilitation technology professionals in Japan. A cross-sectional survey was conducted using a questionnaire to gather relevant data. [Participants and Methods] Data from 112 rehabilitation technology professionals, including physical and occupational therapists as well as speech-language pathologists, were analyzed. Questionnaires were utilized to collect data on participant characteristics, reasons for employment, virtual competence, self-esteem, burnout levels, self-compassion responses, subjective health assessments, and feelings of isolation. [Results] Multiple regression analysis indicated that the regression coefficients of the Lubben Social Network Scale-6, the World Health Organization-five well-being index, the virtual ability scale, the self-esteem scale, and the reasons for employment scale scores were -0.168, -0.191, -0.273, -0.197, and -0.329, respectively. Additionally, structural equation modeling was used to verify the goodness-of-fit indices. The burnout scale scores exhibited a satisfactory fit with the Lubben Social Network Scale-6, the World Health Organization-five well-being index, the virtual ability scale, the self-esteem scale, and the reasons for employment, as indicated by all goodness-of-fit indices. [Conclusion] This study revealed a significant association between the reason for employment and burnout tendency, which was found to be the strongest. Therefore, it is important to know the reason for employment to ascertain burnout tendencies. Conversely, as associations were also found for several adjustment variables, it is necessary to consider not only the reasons for employment but also other factors when assessing burnout tendencies.

2.
Cogn Psychol ; 146: 101606, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37748253

RESUMO

Mathematical expressions consist of recursive combinations of numbers, variables, and operators. According to theoretical linguists, the syntactic mechanisms of natural language also provide a basis for mathematics. To date, however, no theoretically rigorous investigation has been conducted to support such arguments. Therefore, this study uses a methodology based on theoretical linguistics to analyze the syntactic properties of mathematical expressions. Through a review of recent behavioral and neuroimaging studies on mathematical syntax, we report several inconsistencies with theoretical linguistics, such as the use of ternary structures. To address these, we propose that a syntactic category called Applicative plays a central role in analyzing mathematical expressions with seemingly ternary structures by combining binary structures. Besides basic arithmetic expressions, we also examine algebraic equations and complex expressions such as integral and differential calculi. This study is the first attempt at building a comprehensive framework for analyzing the syntactic structures of mathematical expressions.


Assuntos
Idioma , Linguística , Humanos , Matemática
3.
Nat Plants ; 9(8): 1236-1251, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37563460

RESUMO

Common buckwheat, Fagopyrum esculentum, is an orphan crop domesticated in southwest China that exhibits heterostylous self-incompatibility. Here we present chromosome-scale assemblies of a self-compatible F. esculentum accession and a self-compatible wild relative, Fagopyrum homotropicum, together with the resequencing of 104 wild and cultivated F. esculentum accessions. Using these genomic data, we report the roles of transposable elements and whole-genome duplications in the evolution of Fagopyrum. In addition, we show that (1) the breakdown of heterostyly occurs through the disruption of a hemizygous gene jointly regulating the style length and female compatibility and (2) southeast Tibet was involved in common buckwheat domestication. Moreover, we obtained mutants conferring the waxy phenotype for the first time in buckwheat. These findings demonstrate the utility of our F. esculentum assembly as a reference genome and promise to accelerate buckwheat research and breeding.


Assuntos
Fagopyrum , Fagopyrum/genética , Domesticação , Melhoramento Vegetal , Mapeamento Cromossômico , Sequência de Bases
4.
Front Pharmacol ; 13: 890048, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36034871

RESUMO

Hochuekkito (HET) is a Kampo medicine used to treat postoperative and post-illness general malaise and decreased motivation. HET is known to regulate immunity and modulate inflammation. However, the precise mechanism and effects of HET on inflammation-induced central nervous system disorders remain unclear. This study aimed to assess the effect of HET on inflammation-induced anxiety-like behavior and the mechanism underlying anxiety-like behavior induced by lipopolysaccharide (LPS). Institute of Cancer Research mice were treated with LPS (300 µg/kg, intraperitoneally), a bacterial endotoxin, to induce systemic inflammation. The mice were administered HET (1.0 g/kg, orally) once a day for 2 weeks before LPS treatment. The light-dark box test and the hole-board test were performed 24 h after the LPS injection to evaluate the effects of HET on anxiety-like behaviors. Serum samples were obtained at 2, 5, and 24 h after LPS injection, and interleukin-6 (IL-6) levels in serum were measured. Human and mouse macrophage cells (THP-1 and RAW264.7 cells, respectively) were used to investigate the effect of HET on LPS-induced IL-6 secretion. The repeated administration of HET prevented anxiety-like behavior and decreased serum IL-6 levels in LPS-treated mice. HET significantly suppressed LPS-induced IL-6 secretion in RAW264.7 and THP-1 cells. Similarly, glycyrrhizin, one of the chemical constituents of HET, suppressed LPS-induced anxiety-like behaviors. Our study revealed that HET ameliorated LPS-induced anxiety-like behavior and inhibited IL-6 release in vivo and in vitro. Therefore, we postulate that HET may be useful against inflammation-induced anxiety-like behavior.

5.
Eur J Pharmacol ; 904: 174195, 2021 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-34004209

RESUMO

Benzodiazepine receptor agonists are widely prescribed therapeutic agents that alter gamma-aminobutyric acid (GABA)A receptor activity and have anxiolytic effects. Post-operative use of benzodiazepines is a risk factor of delirium. Inflammatory conditions alter the anxiolytic effects of benzodiazepine. We investigated the effect of diazepam, a typical benzodiazepine anxiolytic, on changes in the emotional behavior of mice in a hole-board test after lipopolysaccharide (LPS) treatment. Diazepam dose-dependently increased the number of head-dips at doses that did not alter locomotor activity; however, diazepam dose-dependently significantly decreased the number of head-dips at doses that did not alter locomotor activity in LPS-treated mice. Flumazenil, a benzodiazepine receptor antagonist, normalized the decrease in head-dipping behavior caused by diazepam treatment in normal and LPS-treated mice. The decrease of the head-dipping effect caused by diazepam was attenuated by minocycline in LPS-treated mice. We further found that the decrease in head-dipping behavior caused by diazepam was blocked by bumetanide, a Na+-K+-2Cl- cotransporter isoform 1 (NKCC1) antagonist, in LPS-treated mice. These findings suggest that diazepam induces the anxiety-like behavior under inflammation conditions, and may cause the GABAA receptor dysfunction associated with the chloride plasticity mediated by NKCC1, which contributes to benzodiazepine-induced delirium after surgery.


Assuntos
Ansiolíticos/farmacologia , Ansiedade/prevenção & controle , Bumetanida/farmacologia , Diazepam/farmacologia , Agonistas de Receptores de GABA-A/farmacologia , Inibidores de Simportadores de Cloreto de Sódio e Potássio/farmacologia , Animais , Ansiolíticos/toxicidade , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Comportamento Animal/efeitos dos fármacos , Bicuculina/farmacologia , Bicuculina/uso terapêutico , Bumetanida/uso terapêutico , Diazepam/toxicidade , Emoções/efeitos dos fármacos , Flumazenil/farmacologia , Flumazenil/uso terapêutico , Agonistas de Receptores de GABA-A/efeitos adversos , Antagonistas de Receptores de GABA-A/farmacologia , Antagonistas de Receptores de GABA-A/uso terapêutico , Inflamação/induzido quimicamente , Inflamação/complicações , Lipopolissacarídeos/toxicidade , Masculino , Camundongos Endogâmicos ICR , Minociclina/farmacologia , Minociclina/uso terapêutico , Atividade Motora/efeitos dos fármacos , Inibidores de Simportadores de Cloreto de Sódio e Potássio/uso terapêutico
6.
PLoS One ; 14(7): e0219354, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31306452

RESUMO

Fruits are nowadays considered important suppliers of anti-oxidant molecules. Apples are particularly rich in phenolic compounds, non-nutritional phytochemicals that play active roles in controlling severe chronic diseases. In this work, 19 phenolic compounds were investigated in both skin and pulp tissues of seven apple accessions across the Malus genus collected at two stages: during fruit development and at harvest. The primary difference in phenolic concentration between wild and domesticated accessions, especially in the pulp, could be explained by the larger growth rate of the domesticated varieties. The proposed dilution effect was also confirmed through the observation of the increased content of procyanidin B2+B4 and phloridzin in russet-skinned apples, known to have higher concentrations of these compounds. The metabolite screening was also accompanied by the expression analysis of 16 polyphenolic genes showing, for nine elements, a higher expression at harvest than during fruit development. Finally, a polyphenolic comparison with red-fleshed apples was also carried out, underlying a larger amount of procyanidins and quercetin-3rhamnoside in the white-fleshed accessions. The results presented and discussed in this work suggest that specific white-fleshed apples, especially with russeted-skin, may play an important role in ameliorating the nutraceutical potential of apple fruit.


Assuntos
Frutas/química , Malus/química , Fenóis/química , Antioxidantes/química , Biflavonoides/química , Catequina/química , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Florizina/química , Compostos Fitoquímicos/química , Análise de Componente Principal , Proantocianidinas/química , Quercetina/química
7.
Plant Mol Biol ; 100(4-5): 367-378, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30937702

RESUMO

KEY MESSAGE: S-RNase was demonstrated to be predominantly recognized by an S locus F-box-like protein and an S haplotype-specific F-box-like protein in compatible pollen tubes of sweet cherry. Self-incompatibility (SI) is a reproductive barrier that rejects self-pollen and inhibits self-fertilization to promote outcrossing. In Solanaceae and Rosaceae, S-RNase-based gametophytic SI (GSI) comprises S-RNase and F-box protein(s) as the pistil and pollen S determinants, respectively. Compatible pollen tubes are assumed to detoxify the internalized cytotoxic S-RNases to maintain growth. S-RNase detoxification is conducted by the Skp1-cullin1-F-box protein complex (SCF) formed by pollen S determinants, S locus F-box proteins (SLFs), in Solanaceae. In Prunus, the general inhibitor (GI), but not pollen S determinant S haplotype-specific F-box protein (SFB), is hypothesized to detoxify S-RNases. Recently, SLF-like proteins 1-3 (SLFL1-3) were suggested as GI candidates, although it is still possible that other proteins function predominantly in GI. To identify the other GI candidates, we isolated four other pollen-expressed SLFL and SFB-like (SFBL) proteins PavSLFL6, PavSLFL7A, PavSFBL1, and PavSFBL2 in sweet cherry. Binding assays with four PavS-RNases indicated that PavSFBL2 bound to PavS1, 6-RNase while the others bound to nothing. PavSFBL2 was confirmed to form an SCF complex in vitro. A co-immunoprecipitation assay using the recombinant PavS6-RNase as bait against pollen extracts and a mass spectrometry analysis identified the SCF complex components of PavSLFLs and PavSFBL2, M-locus-encoded glutathione S-transferase (MGST), DnaJ-like protein, and other minor proteins. These results suggest that SLFLs and SFBLs could act as predominant GIs in Prunus-specific S-RNase-based GSI.


Assuntos
Proteínas F-Box/fisiologia , Proteínas de Plantas/fisiologia , Prunus/metabolismo , Autoincompatibilidade em Angiospermas , Clonagem Molecular , Proteínas F-Box/genética , Proteínas F-Box/metabolismo , Espectrometria de Massas , Filogenia , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Tubo Polínico/metabolismo , Tubo Polínico/fisiologia , Prunus/enzimologia , Reprodução , Ribonucleases/química , Ribonucleases/metabolismo
8.
Appl Opt ; 58(5): A1-A6, 2019 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-30873985

RESUMO

Volumetric displays are attracting attention in fields such as media art and digital signage. In previous research, we developed a method to display multiple images in the same space using a volumetric display. However, because of the nature of the algorithm, the images could not be displayed when they contained a pure black image (in which all the pixel values are "0"). In the current study, we present a revised algorithm that can display such images. Therefore, a wider range of images can be displayed in the same space. Image quality evaluation using structural similarity shows that the proposed algorithm yields images that are superior or equivalent to those of the previous algorithm.

9.
Cornea ; 37(9): 1081-1086, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29952799

RESUMO

PURPOSE: The aim of this study was to investigate the existence of presumed immune cells observed by contact specular microscopy in patients who underwent penetrating keratoplasty (PK) and Descemet stripping automated endothelial keratoplasty (DSAEK). METHODS: This cross-sectional study was conducted on consecutive patients who underwent follow-up visits between January and March 2015 for previously performed PK or DSAEK. Presumed immune cell-suspected "cell-like white dots" were evaluated by scanning slit contact specular microscopy. The association between the grading of presumed immune cells with clinical parameters, such as corneal endothelial cell density, time after surgery, and the titer of steroid administration, was also investigated. RESULTS: A total of 54 eyes of 54 patients who underwent PK (32 eyes/32 patients) and DSAEK (22 eyes/22 patients) were evaluated, and suspected immune cells were observed in all patients. In the PK and DSAEK groups, the number of patients in the presumed immune cell grades 1, 2, 3, and 4 were 19, 10, 2, and 1 and 10, 8, 2, and 2, respectively (P = 0.663). No statistically significant association was found between the immune cell grades and the clinical parameters. CONCLUSIONS: Immune cells were observed on the corneal endothelial grafts in all 54 patients who underwent PK or DSAEK. Although the number of immune cells varied between patients and showed no correlation with clinical parameters, it would be beneficial to conduct a future prospective study to analyze the effect of immune cells on postoperative corneal endothelial cell loss.


Assuntos
Ceratoplastia Endotelial com Remoção da Lâmina Limitante Posterior , Endotélio Corneano/diagnóstico por imagem , Endotélio Corneano/imunologia , Sistema Imunitário/fisiologia , Ceratoplastia Penetrante , Doadores de Tecidos , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos Transversais , Feminino , Seguimentos , Humanos , Masculino , Microscopia/métodos , Pessoa de Meia-Idade , Estudos Prospectivos , Adulto Jovem
10.
PLoS One ; 13(1): e0191306, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29338061

RESUMO

Corneal transparency is maintained by the corneal endothelium through its pump and barrier function. Severe corneal endothelial damage results in dysregulation of water flow and eventually causes corneal haziness and deterioration of visual function. In 2013, we initiated clinical research of cell-based therapy for treating corneal decompensation. In that study, we removed an 8-mm diameter section of damaged corneal endothelium without removing Descemet's membrane (the basement membrane of the corneal endothelium) and then injected cultured human corneal endothelial cells (CECs) into the anterior chamber. However, Descemet's membrane exhibits clinically abnormal structural features [i.e., multiple collagenous excrescences (guttae) and thickening] in patients with Fuchs endothelial corneal dystrophy (FECD) and the advanced cornea guttae adversely affects the quality of vision, even in patients without corneal edema. The turnover time of cornea guttae is also not certain. Therefore, we used a rabbit model to evaluate the feasibility of Descemet's membrane removal in the optical zone only, by performing a small 4-mm diameter descemetorhexis prior to CEC injection. We showed that the corneal endothelium is regenerated both on the corneal stroma (the area of Descemet's membrane removal) and on the intact peripheral Descemet's membrane, based on the expression of function-related markers and the restoration of corneal transparency. Recovery of the corneal transparency and central corneal thickness was delayed in areas of Descemet's membrane removal, but the cell density of the regenerated corneal endothelium and the thickness of the central corneal did not differ between the areas with and without residual Descemet's membrane at 14 days after CEC injection. Here, we demonstrate that removal of a pathological Descemet's membrane by a small descemetorhexis is a feasible procedure for use in combination with cell-based therapy. The current strategy might be beneficial for improving visual quality after CEC injection as a treatment for FECD.


Assuntos
Terapia Baseada em Transplante de Células e Tecidos , Transplante de Córnea , Distrofia Endotelial de Fuchs/terapia , Idoso , Animais , Terapia Combinada , Lâmina Limitante Posterior/cirurgia , Modelos Animais de Doenças , Endotélio Corneano/patologia , Estudos de Viabilidade , Feminino , Distrofia Endotelial de Fuchs/patologia , Distrofia Endotelial de Fuchs/cirurgia , Humanos , Masculino , Coelhos
11.
Graefes Arch Clin Exp Ophthalmol ; 256(4): 751-757, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29302788

RESUMO

PURPOSE: This study investigates the possible role of the filtration bleb in the continuous decrease in corneal endothelial cell (CEC) density observed following trabeculectomy. METHODS: This study involved 51 eyes of 37 glaucoma patients who underwent trabeculectomy. The CEC density was determined by contact specular microscopy in three areas: (1) the cornea center, (2) near the trabeculectomy filtration bleb, and (3) the opposite side of the bleb. The eyes were grouped according to post-surgical follow-up years: 0-1 (Group 1), 1-2 (Group 2), 2-3 (Group 3), 3-4, (Group 4), and 4+ years (Group 5). RESULTS: The mean CEC densities at the opposite side of the bleb, in the cornea center, and near the bleb were 2210 ± 487, 1930 ± 528, and 1519 ± 507 cells/mm2, respectively, in all eyes. The CEC density was significantly lower near the bleb than at the other two sites. The coefficient of variation was significantly higher near the bleb than at the other two sites. The CEC densities at the cornea center and at the opposite side of the bleb showed no significant differences. However, the CEC densities near the bleb showed time-dependent decreases to 1790, 1601, 1407, 1339, and 1224 cells/mm2 for Groups 1, 2, 3, 4, and 5, respectively. CONCLUSIONS: CEC density following trabeculectomy decreased near the bleb, but not at the cornea center, suggesting that the involvement of the filtration bleb in CEC density loss should be further examined to elucidate the pathology of CEC loss following trabeculectomy.


Assuntos
Endotélio Corneano/patologia , Glaucoma/cirurgia , Pressão Intraocular , Microscopia/métodos , Trabeculectomia , Idoso , Idoso de 80 Anos ou mais , Contagem de Células , Feminino , Seguimentos , Glaucoma/patologia , Glaucoma/fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade , Período Pós-Operatório , Estudos Retrospectivos
12.
Bioorg Med Chem ; 25(21): 5962-5967, 2017 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-28986115

RESUMO

A convenient strategy to purify oligonucleotides (ONs) synthesized by solid phase synthesis on an automatic DNA/RNA synthesizer was described. By attaching a photocleavable azide linker as the last phosphoramidite unit in the ON synthesis, only the desired full-length sequence was 'caught' on a controlled pore glass (CPG) resin possessing an aza-dimethoxycyclooctyne (DIBAC) derivative. Washing the resulting CPG resin to remove all unbounded species, the subsequent photoirradiation allowed the pure ONs to be 'released' without leaving any chemical modifications on native ON structure or chemical reagents from the solid phase ON synthesis.


Assuntos
Alcinos/química , Azidas/química , Oligonucleotídeos/isolamento & purificação , Raios Ultravioleta , Cromatografia Líquida de Alta Pressão , Reação de Cicloadição , Estrutura Molecular , Oligonucleotídeos/síntese química , Oligonucleotídeos/química , Processos Fotoquímicos
13.
PLoS One ; 11(6): e0158427, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27355373

RESUMO

The corneal endothelium maintains corneal transparency by its pump and barrier functions; consequently, its decompensation due to any pathological reason causes severe vision loss due to corneal haziness. Corneal transplantation is the only therapeutic choice for treating corneal endothelial dysfunction, but associated problems, such as a shortages of donor corneas, the difficulty of the surgical procedure, and graft failure, still need to be resolved. Regenerative medicine is attractive to researchers as a means of providing innovative therapies for corneal endothelial dysfunction, as it now does for other diseases. We previously demonstrated the successful regeneration of corneal endothelium in animal models by injecting cultured corneal endothelial cells (CECs) in combination with a Rho kinase (ROCK) inhibitor. The purpose of the present study was to optimize the vehicle for clinical use in cell-based therapy. Our screening of cell culture media revealed that RELAR medium promoted CEC adhesion. We then modified RELAR medium by removing hormones, growth factors, and potentially toxic materials to generate a cell therapy vehicle (CTV) composed of amino acid, salts, glucose, and vitamins. Injection of CECs in CTV enabled efficient engraftment and regeneration of the corneal endothelium in the rabbit corneal endothelial dysfunction model, with restoration of a transparent cornea. The CECs retained >85% viability after a 24 hour preservation as a cell suspension in CTV at 4°C and maintained their potency to regenerate the corneal endothelium in vivo. The vehicle developed here is clinically applicable for cell-based therapy aimed at treating the corneal endothelium. Our strategy involves the generation of vehicle from a culture medium appropriate for a given cell type by removing materials that are not favorable for clinical use.


Assuntos
Terapia Baseada em Transplante de Células e Tecidos/métodos , Células Endoteliais/citologia , Endotélio Corneano/fisiopatologia , Quinases Associadas a rho/antagonistas & inibidores , Animais , Adesão Celular , Técnicas de Cultura de Células , Sobrevivência Celular , Transplante de Córnea/métodos , Meios de Cultura , Endotélio Corneano/citologia , Estudos de Viabilidade , Humanos , Coelhos , Regeneração , Medicina Regenerativa
14.
Plant Mol Biol ; 91(4-5): 459-69, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27071402

RESUMO

Many species in the Rosaceae, the Solanaceae, and the Plantaginaceae exhibit S-RNase-based gametophytic self-incompatibility (GSI). This system comprises S-ribonucleases (S-RNases) as the pistil S determinant and a single or multiple F-box proteins as the pollen S determinants. In Prunus, pollen specificity is determined by a single S haplotype-specific F-box protein (SFB). The results of several studies suggested that SFB exerts cognate S-RNase cytotoxicity, and a hypothetical general inhibitor (GI) is assumed to detoxify S-RNases in non-specific manner unless it is affected by SFB. Although the identity of the GI is unknown, phylogenetic and evolutionary analyses have indicated that S locus F-box like 1-3 (or S locus F-box with low allelic sequence polymorphism 1-3; SLFL1-3), which are encoded by a region of the Prunus genome linked to the S locus, are good GI candidates. Here, we examined the biochemical characteristics of SLFL1-3 to determine whether they have appropriate GI characteristics. Pull-down assays and quantitative expression analyses indicated that Prunus avium SLFL1-3 mainly formed a canonical SCF complex with PavSSK1 and PavCul1A. Binding assays with PavS(1,3,4,6)-RNases showed that PavSLFL1, PavSLFL2, and PavSLFL3 bound to PavS(3)-RNase, all PavS-RNases tested, and none of the PavS-RNases tested, respectively. Together, these results suggested that SLFL2 has the appropriate characteristics to be the GI in sweet cherry pollen, while SLFL1 may redundantly work with SLFL2 to detoxify all S-RNases. We discuss the possible roles of SLFL1-3 as the GI in the Prunus-specific S-RNase-based GSI mechanism.


Assuntos
Proteínas F-Box/metabolismo , Proteínas de Plantas/metabolismo , Prunus/enzimologia , Prunus/fisiologia , Ribonucleases/metabolismo , Autoincompatibilidade em Angiospermas , Proteínas F-Box/genética , Haplótipos/genética , Complexos Multiproteicos/metabolismo , Proteínas de Plantas/genética , Pólen/genética , Especificidade da Espécie
15.
Phys Rev Lett ; 110(15): 157402, 2013 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-25167311

RESUMO

Hydrophilicity or hydrophobicity is a macroscopic property of the surface, and its atomic scale understanding has not been established. We have studied adsorption of water molecules on the "hydrophobic" carbon nanotube surface at room temperature in water vapor. Based on optical measurements of individual single-walled carbon nanotubes suspended between micropillars in water vapor together with molecular dynamics simulations, we found that water molecules form a stable adsorption layer of 1-2 ML thickness on the nanotube surface and they show rapid adsorption and desorption transition at a critical pressure. This adsorption layer is created by lateral hydrogen bonding of water molecules confined in the weak van der Waals potential of the surface. In spite of hydrophobic hydration, carbon nanotubes exhibit hydrophobicity macroscopically.

16.
Plant Physiol ; 159(3): 1252-62, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22548785

RESUMO

Many species in Rosaceae, Solanaceae, and Plantaginaceae exhibit S-RNase-based self-incompatibility (SI). In this system, the pistil and pollen specificities are determined by S-RNase and the S locus F-box protein, respectively. The pollen S determinant F-box protein in Prunus (Rosaceae) is referred to by two different terms, SFB (for S-haplotype-specific F-box protein) and SLF (for S locus F box), whereas it is called SLF in Solanaceae and Plantaginaceae. Prunus SFB is thought to be a molecule indispensable for its cognate S-RNase to exert cytotoxicity and to arrest pollen tube growth in incompatible reactions. Although recent studies have demonstrated the molecular function of SCF(SLF) in the SI reaction of Solanaceae and Plantaginaceae, how SFB participates in the Prunus SI mechanism remains to be elucidated. Here we report the identification of sweet cherry (Prunus avium) SFB (PavSFB)-interacting Skp1-like1 (PavSSK1) using a yeast (Saccharomyces cerevisiae) two-hybrid screening against the pollen cDNA library. Phylogenetic analysis showed that PavSSK1 belongs to the same clade as Antirrhinum hispanicum SLF-interacting Skp1-like1 and Petunia hybrida SLF-interacting Skp1-like1 (PhSSK1). In yeast, PavSSK1 interacted not only with PavSFBs from different S haplotypes and Cullin1-likes (PavCul1s), but also with S-locus F-box-likes. A pull-down assay confirmed the interactions between PavSSK1 and PavSFB and between PavSSK1 and PavCul1s. These results collectively indicate that PavSSK1 could be a functional component of the SCF complex and that PavSFB may function as a component of the SCF complex. We discuss the molecular function of PavSFB in self-/nonself-recognition in the gametophytic SI of Prunus.


Assuntos
Proteínas F-Box/metabolismo , Loci Gênicos/genética , Proteínas de Plantas/metabolismo , Pólen/genética , Prunus/genética , Proteínas Quinases Associadas a Fase S/metabolismo , Autoincompatibilidade em Angiospermas/fisiologia , Sequência de Aminoácidos , Proteínas F-Box/química , Proteínas F-Box/genética , Regulação da Expressão Gênica de Plantas , Genes de Plantas/genética , Haplótipos/genética , Dados de Sequência Molecular , Petunia/metabolismo , Filogenia , Proteínas de Plantas/química , Proteínas de Plantas/genética , Ligação Proteica , Estrutura Secundária de Proteína , Estrutura Terciária de Proteína , Prunus/metabolismo , Ribonucleases/metabolismo , Saccharomyces cerevisiae/metabolismo , Alinhamento de Sequência , Técnicas do Sistema de Duplo-Híbrido
17.
J Agric Food Chem ; 60(13): 3418-23, 2012 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-22409307

RESUMO

As a preliminary study, we have found that honey from manuka (Leptospermum scoparium) in New Zealand inhibits myeloperoxidase (MPO) activity. In this study, using a chromatographic technique, we isolated two active compounds for MPO-inhibition from manuka honey. One is methyl syringate (MSYR), and the other was identified as a novel glycoside of MSYR, methyl syringate 4-O-ß-D-gentiobiose, which has been named "leptosin" after the genus Leptospermum . The amount of the glycoside ranged from 0.2 to 1.2 µmol/g honey. Leptosin was only found in honeys from the Oceania region, and abundantly in manuka honey including jelly bush honey from Leptospermum polygalifolium in Australia. Therefore, leptosin may be a good chemical marker for manuka honey. Interestingly, the concentration of leptosin in manuka honey was positively correlated with the unique manuka factor (UMF) value, which is expressed as phenol equivalents of its bactericidal activity.


Assuntos
Glicosídeos/análise , Mel/análise , Leptospermum/química , Antibacterianos/análise , Antibacterianos/farmacologia , Biomarcadores/análise , Inibidores Enzimáticos/análise , Inibidores Enzimáticos/farmacologia , Glicosídeos/farmacologia , Humanos , Peroxidase/análise , Peroxidase/antagonistas & inibidores , Infecções Estafilocócicas/microbiologia , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus aureus/isolamento & purificação
18.
PLoS One ; 7(2): e31264, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22312442

RESUMO

The different forms of flowers in a species have attracted the attention of many evolutionary biologists, including Charles Darwin. In Fagopyrum esculentum (common buckwheat), the occurrence of dimorphic flowers, namely short-styled and long-styled flowers, is associated with a type of self-incompatibility (SI) called heteromorphic SI. The floral morphology and intra-morph incompatibility are both determined by a single genetic locus named the S-locus. Plants with short-styled flowers are heterozygous (S/s) and plants with long-styled flowers are homozygous recessive (s/s) at the S-locus. Despite recent progress in our understanding of the molecular basis of flower development and plant SI systems, the molecular mechanisms underlying heteromorphic SI remain unresolved. By examining differentially expressed genes from the styles of the two floral morphs, we identified a gene that is expressed only in short-styled plants. The novel gene identified was completely linked to the S-locus in a linkage analysis of 1,373 plants and had homology to EARLY FLOWERING 3. We named this gene S-LOCUS EARLY FLOWERING 3 (S-ELF3). In an ion-beam-induced mutant that harbored a deletion in the genomic region spanning S-ELF3, a phenotype shift from short-styled flowers to long-styled flowers was observed. Furthermore, S-ELF3 was present in the genome of short-styled plants and absent from that of long-styled plants both in world-wide landraces of buckwheat and in two distantly related Fagopyrum species that exhibit heteromorphic SI. Moreover, independent disruptions of S-ELF3 were detected in a recently emerged self-compatible Fagopyrum species and a self-compatible line of buckwheat. The nonessential role of S-ELF3 in the survival of individuals and the prolonged evolutionary presence only in the genomes of short-styled plants exhibiting heteromorphic SI suggests that S-ELF3 is a suitable candidate gene for the control of the short-styled phenotype of buckwheat plants.


Assuntos
Fagopyrum/genética , Fagopyrum/fisiologia , Flores/anatomia & histologia , Genoma de Planta/genética , Proteínas de Plantas/genética , Autoincompatibilidade em Angiospermas/genética , Sequência de Aminoácidos , Fagopyrum/anatomia & histologia , Fagopyrum/metabolismo , Flores/genética , Flores/metabolismo , Flores/fisiologia , Perfilação da Expressão Gênica , Mutagênese , Proteínas de Plantas/química , Proteínas de Plantas/metabolismo , RNA de Plantas/genética , Especificidade da Espécie
19.
Genes Genet Syst ; 83(5): 393-401, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19168990

RESUMO

We have constructed a BAC library for common buckwheat Fagopyrum esculentum Moench. The library includes 142,005 clones with an average insert size of approximately 76 kb, equivalent to approximately a 7 to approximately 8-fold coverage of the genome. Polymerase chain reaction based screening of the library with AGAMOUS and FLORICAULA/LEAFY primers, has identified 7 and 9 BACs, respectively, which are consistent with the genome coverage. This library represents the first large insert genomic library for F. esculentum and it can be served as a genetic resource facilitating agricultural, pharmacological, physiological, and evolutionary studies of the species. To demonstrate the utilization of the library for characterizing agriculturally valuable traits, we developed a sequence tagged site marker tightly linked to the dwarf E locus as well as to the self-incompatibility complex locus and screened the library to initiate positional cloning of the causative genes.


Assuntos
Cromossomos Artificiais Bacterianos/genética , Clonagem Molecular/métodos , Fagopyrum/genética , Biblioteca Gênica , Genoma de Planta/genética , DNA de Plantas/análise , Ordem dos Genes , Ligação Genética
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