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1.
Front Health Serv ; 3: 1154989, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37720846

RESUMEN

Background: The aim of the study is to improve the policy of health authorities regarding registered nurses (RNs) staffing by understanding how the health outcomes of hemodialysis (HD) patients vary depending on the level of HD nursing experience of at least 2 years. Methods: The study included 21,839 patients who started maintenance HD for 3 months in early 2013 in the same medical institutions. Demographic variables such as sex, age, and causes of HD; institutional variables such as type of institution and number of RNs; and health outcomes such as HD adequacy, systolic and diastolic blood pressure (SBP, DBP), hemoglobin (Hb), and serum albumin were collected through web-based questionnaires. To determine the relationship between variables, t-test, chi-square test, and ANOVA were employed. Binary logistic regression was used to examine the odds ratio. Results: Institutions with 100% of experienced RNs with at least 2 years of experience in HD units were found to have higher NKF K-DOQI criteria satisfaction rate than Institutions with <50% of experienced RNs with at least 2 years of experience in HD units for all health outcomes, except DBP (42.9% vs. 38.8%, p < .001) and Hb (27.8% vs. 24.4%, p < .001). Four of the six health-related variables-HD adequacy (Kt/v, urea reduction rate, URR), SBP, and serum albumin-were higher in institutions with 100% of experienced RNs than those with less than 50%. Conclusions: In order to improve HD patients' health outcomes, HD institutions should prioritize recruiting RNs who are proficient in HD care. A higher proportion of skilled RNs results in a higher ability to prepare for emergencies and early detection of patient complications. RNs with extensive experience in HD nursing, therefore, promote quality management of HD patients.

2.
JMIR Serious Games ; 10(4): e38988, 2022 Nov 24.
Artículo en Inglés | MEDLINE | ID: mdl-36422882

RESUMEN

BACKGROUND: There are limitations to conducting face-to-face classes following the recent COVID-19 pandemic. Web-based education is no longer a temporary form of teaching and learning during unusual events, such as pandemics, but has proven to be necessary to uphold in parallel with offline education in the future. Therefore, it is necessary to scientifically organize the priorities of a learner needs analysis by systematically and rationally investigating and analyzing the needs of learners for the development of virtual reality (VR) programs for core nursing skills (CNS). OBJECTIVE: This study aimed to identify the priorities of learners' needs for the development of VR programs for CNS using the Locus for Focus Model and Borich need assessment model. METHODS: The participants included nursing students in South Korea who were in their second year or higher and had taken courses in fundamental nursing or CNS-related classes. The survey took place from May 20 to June 25, 2021. A total of 337 completed questionnaires were collected. Of these, 222 were used to conduct the final analysis. The self-report questionnaire consisted of 3 parts: perception of VR programs, demand for developing VR programs, and general characteristics. The general characteristics of the participants were analyzed using descriptive statistics. To determine the priority of the demand for developing VR programs for CNS, the Locus for Focus Model and the Borich priority formula were used. RESULTS: In all, 7 skills were identified as being of the top priority for development, including intramuscular injection, intradermal injection, tube feeding, enema, postoperative care, supplying oxygen via nasal cannula, and endotracheal suction. CONCLUSIONS: The analysis showed that nursing students generally needed and prioritized the development of VR programs for the nursing skills involving invasive procedures. The results of this study are intended to help in various practical education classes using VR programs in nursing departments, which are currently facing difficulties in teaching CNS on the web owing to COVID-19.

3.
Iperception ; 12(6): 20416695211055767, 2021 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-34888028

RESUMEN

Individual differences in colour perception, as evidenced by the popular debate of "The Dress" picture, have garnered additional interest with the popularisation of additional, similar photographs. We investigated which colorimetric characteristics were responsible for individual differences in colour perception. All objects of the controversial photographs are composed of two representative colours, which are low in saturation and are either complementary to each other or reminiscent of complementary colours. Due to these colorimetric characteristics, we suggest that one of the two complementary pixel clusters should be estimated as the illuminant hue depending on assumed brightness. Thus, people perceive the object's colours as being biased toward complementarily different colour directions and perceive different pixel clusters as chromatic and achromatic. Even though the distance between colours that people perceive differently is small in colour space, people perceive the object's colour as differently categorized colours in these ambiguous photographs, thereby causing debate. We suggest that people perceive the object's colours using different "modes of colour appearance" between surface-colour and self-luminous modes.

4.
Nat Commun ; 12(1): 6805, 2021 11 23.
Artículo en Inglés | MEDLINE | ID: mdl-34815401

RESUMEN

GPR158, a class C orphan GPCR, functions in cognition, stress-induced mood control, and synaptic development. Among class C GPCRs, GPR158 is unique as it lacks a Venus flytrap-fold ligand-binding domain and terminates Gαi/o protein signaling through the RGS7-Gß5 heterodimer. Here, we report the cryo-EM structures of GPR158 alone and in complex with one or two RGS7-Gß5 heterodimers. GPR158 dimerizes through Per-Arnt-Sim-fold extracellular and transmembrane (TM) domains connected by an epidermal growth factor-like linker. The TM domain (TMD) reflects both inactive and active states of other class C GPCRs: a compact intracellular TMD, conformations of the two intracellular loops (ICLs) and the TMD interface formed by TM4/5. The ICL2, ICL3, TM3, and first helix of the cytoplasmic coiled-coil provide a platform for the DHEX domain of one RGS7 and the second helix recruits another RGS7. The unique features of the RGS7-binding site underlie the selectivity of GPR158 for RGS7.


Asunto(s)
Subunidades beta de la Proteína de Unión al GTP/ultraestructura , Proteínas RGS/ultraestructura , Receptores Acoplados a Proteínas G/ultraestructura , Microscopía por Crioelectrón , Subunidades beta de la Proteína de Unión al GTP/genética , Subunidades beta de la Proteína de Unión al GTP/aislamiento & purificación , Subunidades beta de la Proteína de Unión al GTP/metabolismo , Células HEK293 , Humanos , Proteínas RGS/genética , Proteínas RGS/aislamiento & purificación , Proteínas RGS/metabolismo , Receptores Acoplados a Proteínas G/genética , Receptores Acoplados a Proteínas G/aislamiento & purificación , Receptores Acoplados a Proteínas G/metabolismo , Proteínas Recombinantes/genética , Proteínas Recombinantes/aislamiento & purificación , Proteínas Recombinantes/metabolismo , Proteínas Recombinantes/ultraestructura
5.
J Mol Biol ; 432(22): 5966-5984, 2020 11 06.
Artículo en Inglés | MEDLINE | ID: mdl-33058878

RESUMEN

The neurotransmitter γ-aminobutyric acid (GABA) activates the metabotropic GABAB receptor to generate slow, prolonged inhibitory signals that regulate the neural circuitry. The GABAB receptor is an obligate heterodimeric G protein-coupled receptor (GPCR) comprised of GBR1 and GBR2 subunits, each with extracellular, seven-helix transmembrane (7TM), and coiled-coil domains. To understand how GABA-driven conformational changes in the extracellular domain are transmitted to the 7TM domain during signal transduction, we determined cryo-electron microscopy (EM) structures of GABAB in two different states: an antagonist-bound inactive state, and an active state in which both the GABA agonist and a positive allosteric modulator (PAM) are bound. In the inactive state, the TM3 and TM5 helices in the two 7TM domains engage in cholesterol-mediated as well as direct interactions, resulting in an open conformation. GABA binding forces the extracellular domains of GBR1 and GBR2 into a compact form, relocating the linkers that connect the extracellular and 7TM domains closer to each other. The movement of the linker along with the associated extracellular loop 2 of the 7TM domain reorients the two 7TM domains and creates a new interface with the TM5, TM6 and TM7 helices in a closed conformation. PAM binding to the interface between the TM6 and TM6 helices stabilizes the active 7TM domain conformation. The relayed structural rearrangement results in significant conformational changes in the TM helices, as well as intracellular loop 3 in GBR2, which may promote the binding and activation of the Gi/o proteins.


Asunto(s)
Dimerización , Receptores de GABA-B/química , Receptores de GABA-B/metabolismo , Sitios de Unión , Membrana Celular/metabolismo , Microscopía por Crioelectrón , Humanos , Modelos Moleculares , Unión Proteica , Conformación Proteica , Dominios Proteicos , Multimerización de Proteína , Subunidades de Proteína/química , Subunidades de Proteína/metabolismo , Receptores de GABA-B/genética , Transducción de Señal , Relación Estructura-Actividad , Ácido gamma-Aminobutírico/metabolismo
6.
Nucleic Acids Res ; 48(6): 3328-3342, 2020 04 06.
Artículo en Inglés | MEDLINE | ID: mdl-32002546

RESUMEN

Monoubiquitination of the Fanconi anemia complementation group D2 (FANCD2) protein by the FA core ubiquitin ligase complex is the central event in the FA pathway. FANCA and FANCG play major roles in the nuclear localization of the FA core complex. Mutations of these two genes are the most frequently observed genetic alterations in FA patients, and most point mutations in FANCA are clustered in the C-terminal domain (CTD). To understand the basis of the FA-associated FANCA mutations, we determined the cryo-electron microscopy (EM) structures of Xenopus laevis FANCA alone at 3.35 Å and 3.46 Å resolution and two distinct FANCA-FANCG complexes at 4.59 and 4.84 Å resolution, respectively. The FANCA CTD adopts an arc-shaped solenoid structure that forms a pseudo-symmetric dimer through its outer surface. FA- and cancer-associated point mutations are widely distributed over the CTD. The two different complex structures capture independent interactions of FANCG with either FANCA C-terminal HEAT repeats, or the N-terminal region. We show that mutations that disturb either of these two interactions prevent the nuclear localization of FANCA, thereby leading to an FA pathway defect. The structure provides insights into the function of FANCA CTD, and provides a framework for understanding FA- and cancer-associated mutations.


Asunto(s)
Proteína del Grupo de Complementación A de la Anemia de Fanconi/ultraestructura , Proteína del Grupo de Complementación D2 de la Anemia de Fanconi/ultraestructura , Proteína del Grupo de Complementación G de la Anemia de Fanconi/ultraestructura , Anemia de Fanconi/genética , Animales , Núcleo Celular/genética , Núcleo Celular/ultraestructura , Microscopía por Crioelectrón , Cristalografía por Rayos X , Proteínas de Unión al ADN/genética , Proteínas de Unión al ADN/ultraestructura , Anemia de Fanconi/patología , Proteína del Grupo de Complementación A de la Anemia de Fanconi/genética , Proteína del Grupo de Complementación D2 de la Anemia de Fanconi/genética , Proteína del Grupo de Complementación G de la Anemia de Fanconi/química , Humanos , Complejos Multiproteicos/química , Complejos Multiproteicos/genética , Mutación , Unión Proteica/genética , Conformación Proteica , Xenopus laevis/genética
7.
J Immunol Methods ; 463: 84-88, 2018 12.
Artículo en Inglés | MEDLINE | ID: mdl-30237054

RESUMEN

Rubella virus is a critical infectious pathogen to healthcare workers but is preventable by vaccination. In this study, we used three immunoassays - LIAISON Rubella IgG, ARCHITECT Rubella IgG, and AtheNA Multi-Lyte MMRV IgG - to detect rubella virus IgG and tested 182 serum specimens. The percentage of positives with the three Rubella tests were as follows: LIAISON, 71.9%; ARCHITECT, 83.5%; and AtheNA, 99.5%. The three assays showed an overall agreement rate of 71.9%. The rates of seropositive detection with LIAISON, ARCHITECT, and AtheNA among healthcare workers with and without self-reporting history of past infection or vaccination were 70.7% and 90.9%, 83.6% and 81.8%, and 99.4% and 100%, respectively. The three immunoassays showed a low agreement rate for rubella virus IgG. Therefore, choosing accurate and appropriate IgG assay methods is very important for effective infection control and prevention.


Asunto(s)
Anticuerpos Antivirales/sangre , Personal de Salud , Inmunoglobulina G/sangre , Virus de la Rubéola , Rubéola (Sarampión Alemán)/sangre , Adulto , Femenino , Humanos , Inmunoensayo/métodos , Masculino , Reproducibilidad de los Resultados
8.
Nat Struct Mol Biol ; 24(3): 248-257, 2017 03.
Artículo en Inglés | MEDLINE | ID: mdl-28134932

RESUMEN

The Rad50 hook interface is crucial for assembly and various functions of the Mre11 complex. Previous analyses suggested that Rad50 molecules interact within (intracomplex) or between (intercomplex) dimeric complexes. In this study, we determined the structure of the human Rad50 hook and coiled-coil domains. The data suggest that the predominant structure is the intracomplex, in which the two parallel coiled coils proximal to the hook form a rod shape, and that a novel interface within the coiled-coil domains of Rad50 stabilizes the interaction of Rad50 protomers in the dimeric assembly. In yeast, removal of the coiled-coil interface compromised Tel1 activation without affecting DNA repair, while simultaneous disruption of that interface and the hook phenocopied a null mutation. The results demonstrate that the hook and coiled-coil interfaces coordinately promote intracomplex assembly and define the intracomplex as the functional form of the Mre11 complex.


Asunto(s)
Enzimas Reparadoras del ADN/química , Enzimas Reparadoras del ADN/metabolismo , Proteínas de Unión al ADN/química , Proteínas de Unión al ADN/metabolismo , Células Eucariotas/metabolismo , Multimerización de Proteína , Ácido Anhídrido Hidrolasas , Secuencia de Aminoácidos , Puntos de Control del Ciclo Celular , Cristalografía por Rayos X , Roturas del ADN de Doble Cadena , Reparación del ADN , Transferencia Resonante de Energía de Fluorescencia , Humanos , Meiosis , Modelos Biológicos , Proteínas Mutantes/química , Proteínas Mutantes/metabolismo , Dominios Proteicos , Estructura Secundaria de Proteína , Saccharomyces cerevisiae/metabolismo , Transducción de Señal , Soluciones , Zinc/metabolismo
9.
BMC Plant Biol ; 15: 110, 2015 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-25929516

RESUMEN

BACKGROUND: Sugar plays a central role as a source of carbon metabolism and energy production and a signaling molecule in diverse growth and developmental processes and environmental adaptation in plants. It is known that sugar metabolism and allocation between different physiological functions is intimately associated with flowering transition in many plant species. The INDETERMINATE DOMAIN (IDD)-containing transcription factor IDD8 regulates flowering time by modulating sugar metabolism and transport under sugar-limiting conditions in Arabidopsis. Meanwhile, it has been reported that SUCROSE NONFERMENTING-1-RELATED PROTEIN KINASE 1 (SnRK1), which acts as a sensor of cellular energy metabolism, is activated by sugar deprivation. Notably, SnRK1-overexpressing plants and IDD8-deficient mutants exhibit similar phenotypes, including delayed flowering, suggesting that SnRK1 is involved in the IDD8-mediated metabolic control of flowering. RESULTS: We examined whether the sugar deprivation-sensing SnRK1 is functionally associated with IDD8 in flowering time control through biochemical and molecular genetic approaches. Overproduction of AKIN10, the catalytic subunit of SnRK1, delayed flowering in Arabidopsis, as was observed in IDD8-deficient idd8-3 mutant. We found that AKIN10 interacts with IDD8 in the nucleus. Consequently, AKIN10 phosphorylates IDD8 primarily at two serine (Ser) residues, Ser-178 and Ser-182, which reside in the fourth zinc finger (ZF) domain that mediates DNA binding and protein-protein interactions. AKIN10-mediated phosphorylation did not affect the subcellular localization and DNA-binding property of IDD8. Instead, the transcriptional activation activity of the phosphorylated IDD8 was significantly reduced. Together, these observations indicate that AKIN10 antagonizes the IDD8 function in flowering time control, a notion that is consistent with the delayed flowering phenotypes of AKIN10-overexpressing plants and idd8-3 mutant. CONCLUSION: Our data show that SnRK1 and its substrate IDD8 constitute a sugar metabolic pathway that mediates the timing of flowering under sugar deprivation conditions. In this signaling scheme, the SnRK1 signals are directly integrated into the IDD8-mediated gene regulatory network that governs flowering transition in response to fluctuations in sugar metabolism, further supporting the metabolic control of flowering.


Asunto(s)
Proteínas de Arabidopsis/metabolismo , Arabidopsis/metabolismo , Flores , Proteínas Serina-Treonina Quinasas/metabolismo , Factores de Transcripción/metabolismo , Arabidopsis/fisiología , Proteínas de Arabidopsis/genética , Núcleo Celular/metabolismo , Fosforilación , Unión Proteica , Proteínas Serina-Treonina Quinasas/genética , Fracciones Subcelulares/metabolismo , Activación Transcripcional
10.
J Ethnopharmacol ; 160: 41-51, 2015 Feb 03.
Artículo en Inglés | MEDLINE | ID: mdl-25476485

RESUMEN

ETHNOPHARMACOLOGICAL RELEVANCE: Stemona tuberosa (ST) is a traditional herbal medicine used for the treatment of various respiratory diseases in eastern Asia. AIM OF THE STUDY: We investigated the anti-inflammatory effects of a ST water extract in lipopolysaccharide (LPS)-stimulated RAW 264.7 macrophages and in cigarette smoke (CS)-induced lung inflammation mouse models. MATERIALS AND METHODS: RAW 264.7 macrophages were treated with the ST extract and stimulated by LPS. The expressions of pro-inflammatory mediators were evaluated by using nitric oxide (NO) assay, enzyme-linked immunosorbent assay and Western blot analysis. After the C57BL/6 mice were exposed to CS, they were administrated with the ST extract. The accumulated inflammatory cells in the bronchoalveolar lavage fluid (BALF) were counted. Also, real-time polymerase chain reaction and hematoxylin and eosin staining were performed in lung tissues. RESULTS: The ST extract treatment reduced the production of NO via blocking the expressions of cyclooxygenase-2 and inducible nitric oxide synthase protein in RAW 264.7 macrophages. In addition, ST extract treatment decreased the secretions of inflammatory cytokines and regulated NF-κB activation by inhibiting the phosphorylation of IκB and the mitogen-activated protein kinase pathway. Also, ST extract administration to mice reduced the infiltrations of macrophages into BALF and the histological inflammatory changes in lung tissues. Furthermore, administration of the ST extract regulated the levels of tumor necrosis factor-α, interleukin (IL)-6, IL-1ß, monocyte chemoattractant protein-1 and matrix metalloproteinases-12 in the lungs. CONCLUSION: These findings suggested that ST extract attenuated pulmonary inflammatory responses by inhibiting the expression of diverse inflammatory mediators in vivo and in vitro.


Asunto(s)
Antiinflamatorios/farmacología , Inflamación/prevención & control , Activación de Macrófagos/efectos de los fármacos , Macrófagos/efectos de los fármacos , Fitoterapia , Extractos Vegetales/farmacología , Stemonaceae/química , Animales , Antiinflamatorios/uso terapéutico , Líquido del Lavado Bronquioalveolar/citología , Supervivencia Celular/efectos de los fármacos , Células Cultivadas , Inflamación/tratamiento farmacológico , Mediadores de Inflamación/metabolismo , Lipopolisacáridos , Pulmón/efectos de los fármacos , Pulmón/metabolismo , Pulmón/patología , Enfermedades Pulmonares/inducido químicamente , Enfermedades Pulmonares/tratamiento farmacológico , Enfermedades Pulmonares/prevención & control , Macrófagos/citología , Macrófagos/inmunología , Ratones , Extractos Vegetales/química , Extractos Vegetales/uso terapéutico , Lesión por Inhalación de Humo/tratamiento farmacológico , Lesión por Inhalación de Humo/prevención & control
11.
Plant J ; 72(1): 162-72, 2012 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-22672153

RESUMEN

Transcription factors are central constituents of gene regulatory networks that control diverse aspects of plant development and environmental adaptability. Therefore they have been explored for decades as primary targets for agricultural biotechnology. A gene of interest can readily be introduced into many crop plants, whereas targeted gene inactivation is practically difficult in many cases. Here, we developed an artificial small interfering peptide (a-siPEP) approach, which is based on overexpression of specific protein domains, and evaluated its application for the targeted inactivation of transcription factors in the dicot model, Arabidopsis, and monocot model, Brachypodium. We designed potential a-siPEPs of two representative MADS box transcription factors, SUPPRESSOR OF OVEREXPRESSOR OF CONSTANS 1 (SOC1) and AGAMOUS (AG), and a MYB transcription factor, LATE ELONGATED HYPOCOTYL (LHY). Transgenic plants overproducing the a-siPEPs displayed phenotypes comparable to those of gene-deficient mutants. The a-siPEPs attenuate nuclear import and DNA-binding of target transcription factors. Our data demonstrate that the a-siPEP tool is an efficient genetic means of inactivating specific transcription factors in plants.


Asunto(s)
Arabidopsis/genética , Brachypodium/genética , Péptidos/genética , Factores de Transcripción/genética , Proteína AGAMOUS de Arabidopsis/metabolismo , Transporte Activo de Núcleo Celular , Arabidopsis/crecimiento & desarrollo , Arabidopsis/metabolismo , Arabidopsis/ultraestructura , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Biotecnología , Brachypodium/crecimiento & desarrollo , Brachypodium/metabolismo , Brachypodium/ultraestructura , Proteínas de Unión al ADN/genética , Proteínas de Unión al ADN/metabolismo , Flores/genética , Flores/crecimiento & desarrollo , Flores/metabolismo , Expresión Génica , Proteínas de Dominio MADS/genética , Proteínas de Dominio MADS/metabolismo , Modelos Moleculares , Péptidos/metabolismo , Fenotipo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Plantas Modificadas Genéticamente , Multimerización de Proteína , Protoplastos , Factores de Transcripción/metabolismo , Técnicas del Sistema de Dos Híbridos
12.
Chem Commun (Camb) ; 48(25): 3079-81, 2012 Mar 25.
Artículo en Inglés | MEDLINE | ID: mdl-22344411

RESUMEN

trans-1,2-Diaminocyclohexane functionalized mesoporous silica was applied as an ideal catalyst for asymmetric Michael addition of various nitroalkane derivatives. Short channels and plugs in the pore structure offered chiral enhancement in Michael addition.


Asunto(s)
Ciclohexilaminas/química , Dióxido de Silicio/química , Catálisis , Estereoisomerismo
13.
J Food Prot ; 75(1): 118-22, 2012 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-22221363

RESUMEN

The aim of this study was to examine the acaricidal activity of Periploca sepium oil and its active component against Tyrophagus putrescentiae. Based on its 50% lethal dose (LD(50) ) value, P. sepium oil (8.45 µg/cm(2)) was highly active against T. putrescentiae. The active constituent of P. sepium was isolated by chromatographic techniques and identified as 2-hydroxy-4-methoxybenzaldehyde. In the comparison with synthetic acaricides, the acaricidal activity of 2-hydroxy-4-methoxybenzaldehyde (0.94 µg/cm(2)) against T. putrescentiae was 12.2- and 31.2-fold greater than those of benzyl benzoate (11.45 µg/cm(2)) and N,N-diethyl-m-toluamide (29.33 µg/cm(2)), respectively. To establish structure-activity relationships, the acaricidal activities of 2-hydroxy-4-methoxybenzaldehyde and its derivatives against T. putrescentiae were determined by using an impregnated fabric disk bioassay. On the basis of LD(50) values, 4-methoxybenzaldehyde (0.48 µg/cm(2)) was the most effective against T. putrescentiae, followed by 3-methoxybenzaldehyde (0.82 µg/cm(2)), 2-hydroxy-5-methoxybenzaldehyde (0.92 µg/cm(2)), 2-methoxybenzaldehyde (0.95 µg/cm(2)), 2-hydroxybenzaldehyde (0.97 µg/cm(2)), and 2-hydroxy-3-methoxybenzaldehyde (2.35 µg/cm(2)). These results indicate that the introduction of a hydroxyl and/or methoxy group into the benzaldehyde skeleton increased the acaricidal activity. Therefore, 2-hydroxy-4-methoxybenzaldehyde and its derivatives could potentially be used as potent mite control agents.


Asunto(s)
Acaricidas/farmacología , Conservación de Alimentos/métodos , Ácaros/efectos de los fármacos , Periploca/química , Aceites de Plantas/farmacología , Animales , Microbiología de Alimentos , Dosificación Letal Mediana , Ácaros/crecimiento & desarrollo , Control Biológico de Vectores/métodos
14.
Nat Commun ; 2: 303, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-21556057

RESUMEN

Alternative splicing of primary gene transcripts provides eukaryotic cells, with a critical scheme for enriching transcriptome and proteome diversity. Here we report that alternative splicing of the Arabidopsis INDERMINATE DOMAIN 14 (IDD14) transcription factor gene generates a competitive inhibitor in regulating starch metabolism. An alternatively spliced IDD14 form (IDD14ß), which is produced predominantly under cold conditions, lacks functional DNA-binding domain but is able to form heterodimers with the functional IDD14 form (IDD14α). IDD14α-IDD14ß heterodimers have reduced binding activity to the promoter of Qua-Quine Starch (QQS) gene that regulates starch accumulation. Transgenic Arabidopsis plants overproducing IDD14α (35S:IDD14α) exhibited retarded growth with pale green leaves as appeared on QQS-overexpressing plants. Notably, IDD14ß overproduction rescued the 35S:IDD14α phenotypes. We propose that alternative splicing of the IDD14 gene generates a self-controlled regulatory loop that may modulate starch accumulation in response to cold.


Asunto(s)
Empalme Alternativo/genética , Proteínas de Arabidopsis/metabolismo , Arabidopsis/metabolismo , Multimerización de Proteína , Factores de Transcripción/metabolismo , Arabidopsis/genética , Arabidopsis/crecimiento & desarrollo , Proteínas de Arabidopsis/genética , Frío , Proteínas de Unión al ADN/genética , Proteínas de Unión al ADN/metabolismo , Perfilación de la Expresión Génica , Regulación de la Expresión Génica de las Plantas , Variación Genética , Hojas de la Planta/genética , Hojas de la Planta/crecimiento & desarrollo , Hojas de la Planta/metabolismo , Plantas Modificadas Genéticamente/genética , Plantas Modificadas Genéticamente/metabolismo , Proteoma/genética , Proteoma/metabolismo , Almidón/metabolismo , Factores de Transcripción/genética
15.
Chem Commun (Camb) ; 47(16): 4673-5, 2011 Apr 28.
Artículo en Inglés | MEDLINE | ID: mdl-21423992

RESUMEN

Plugged mesoporous SBA-15 having a 2-D hexagonal pore structure could be directly synthesized under acidic conditions using P123 as a supramolecular template, sodium metasilicate and alcoholamines. The use of alcoholamines seemed to play roles as capturing agents for silica sources that could form internal porous plugs.


Asunto(s)
Aminas/química , Dióxido de Silicio/síntesis química , Tamaño de la Partícula , Porosidad , Dióxido de Silicio/química , Propiedades de Superficie
16.
J Hazard Mater ; 185(2-3): 1311-7, 2011 Jan 30.
Artículo en Inglés | MEDLINE | ID: mdl-21055872

RESUMEN

Various adsorbents are available for the removal of heavy and toxic metals, silica-based materials have been the most popular. Recently, there has been considerable interest for the modification of organic moieties and mesostructured materials to enable their use as efficient adsorbent for metal removal. In this study, here we are reporting successful incorporation of tetrakis(4-carboxyphenyl)porphyrin (TCPP) in mesoporous silica by the post-synthetic method. TCPP-SBA-15 has been found to be an effective material for the removal of Cu(II) from aqueous solution due to the chelating nature of the porphyrin-bridging group. A comparative study on adsorption of copper(II) ion over NH(2)-SBA-15 silica and TCPP-SBA-15 was performed. The results show that TCPP-SBA-15 material has higher adsorption capacity than NH(2)-SBA-15 silica and it reaches the adsorption maxima around 13 mmol g(-1).


Asunto(s)
Cobre/aislamiento & purificación , Porfirinas/química , Dióxido de Silicio/química , Contaminantes Químicos del Agua/aislamiento & purificación , Adsorción , Microscopía Electrónica de Rastreo , Espectrofotometría Ultravioleta , Espectroscopía Infrarroja por Transformada de Fourier , Difracción de Rayos X
17.
J Nanosci Nanotechnol ; 10(1): 227-32, 2010 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-20352838

RESUMEN

Side chain alkylation of toluene with methanol was studied over mesoporous zeolite supported MgO catalysts. MgO were supported onto the carbon templated mesoporous silicalite-1 by direct synthesis route under microwave conditions. This direct synthesis route yields the majority of MgO highly dispersed into the mesopores of the silicalite-1 crystals. The vapor phase alkylation of toluene with methanol was performed over these catalysts under vapor phase conditions at atmospheric pressure. Mesoporous silicalite-1 supported MgO catalysts gave improved yields towards side chain alkylated products compared to the bulk MgO. The higher activity exhibited by 5% MgO supported on mesoporous silicalite compared to the one with 1% MgO can be attributed to the large number of weak basic sites observed from the CO2 TPD.


Asunto(s)
Óxido de Magnesio/química , Metanol/química , Tolueno/química , Zeolitas/química , Alquilación , Derivados del Benceno/síntesis química , Nanopartículas , Nitrógeno , Tamaño de la Partícula , Porosidad , Espectrometría Raman , Estireno/síntesis química , Difracción de Rayos X
18.
J Food Prot ; 72(8): 1686-91, 2009 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-19722401

RESUMEN

The acaricidal activities of major constituents from the oil of Juniperus chinensis (var. globosa) leaves were compared with those of DEET (N,N-diethyl-m-toluamide) by using impregnated fabric disk bioassay against Dermatophagoides spp. and Tyrophagus putrescentiae. Toxicity varied with doses as well as chemical composition. The 50% lethal doses (LD50) of J. chinensis oil against Dermatophagoides farinae, Dermatophagoides pteronyssinus, and T. putrescentiae were 21.60, 19.89, and 38.10 microg/cm2, respectively. The active constituent was purified using silica gel chromatography and high-performance liquid chromatography. The acaricidal component was identified as bomyl acetate through gas chromatography-mass spectrometry, 1H nuclear magnetic resonance (NMR), 13C-NMR, 1H-13C shift correlation spectrum-NMR, and distortionless enhancement by polarization transfer-NMR. The LD50 of bornyl acetate (2.94 microg/cm2) against D. farinae was significantly lower than those of DEET (37.13 microg/cm2) and alpha-eudesmol (29.72 microg/cm2). Similar results were observed when bomyl acetate and alpha-eudesmol were tested against D. pteronyssinus and T. putrescentiae. The lower LD50 of bornyl acetate indicates that it may be responsible for the major acaricidal activity against house dust and stored food mites, even though it constitutes only 19.5% of J. chinensis oil. Overall, these findings indicated that bornyl acetate and c-eudesmol have potential for use as control agents against house dust and stored food mites.


Asunto(s)
Acaridae/efectos de los fármacos , Conservación de Alimentos/métodos , Juniperus/química , Aceites Volátiles/farmacología , Pyroglyphidae/efectos de los fármacos , Acaridae/crecimiento & desarrollo , Animales , Bioensayo , DEET/farmacología , Relación Dosis-Respuesta a Droga , Insecticidas , Control Biológico de Vectores , Hojas de la Planta/química , Pyroglyphidae/crecimiento & desarrollo , Especificidad de la Especie
19.
Pest Manag Sci ; 65(3): 327-31, 2009 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-19051215

RESUMEN

BACKGROUND: Various attempts to control the populations of house-dust and stored-food mites have been implemented using synthetic chemicals. Although effective, the repeated use of these chemicals has led to resistance owing to the mite's high reproductive potential and short life cycle. Therefore, this study aimed to develop natural acaricides using oils derived from Leptospermum scoparium JR & G Forst., which may affect the overall biological activity of a mite without adverse effects. Results were compared with those from using benzyl benzoate and N,N-diethyl-3-methylbenzamide (DEET). RESULTS: The LD(50) values of L. scoparium oil were 0.54, 0.67 and 1.12 microg cm(-2) against Dermatophagoides farinae (Hughes), D. pteronyssinus (Troussart) and Tyrophagus putrescentiae (Schrank) respectively. The active constituent isolated from L. scoparium was identified as leptospermone (6-isovaleryl-2,2,4,4-tetramethyl-1,3,5-cyclohexanetrione) by spectroscopic analysis. Based on the LD(50) values of leptospermone and its derivatives, the most toxic compound against D. farinae was leptospermone (0.07 microg cm(-2)), followed by 2,2,4,4,6,6-hexamethyl-1,3,5-cyclohexanetrione (1.21 microg cm(-2)), benzyl benzoate (10.03 microg cm(-2)) and DEET (37.12 microg cm(-2)). Furthermore, similar results were observed when the leptospermone and its derivatives were tested against D. pteronyssinus and T. putrescentiae. CONCLUSIONS: These results indicate that L. scoparium oil-derived materials, particularly leptospermone and 2,2,4,4,6,6-hexamethyl-1,3,5-cyclohexanetrione, have potential for development as new agents for the control of three species of mite.


Asunto(s)
Insecticidas/farmacología , Leptospermum/química , Ácaros/efectos de los fármacos , Aceites Volátiles/farmacología , Aceites de Plantas/farmacología , Animales , Insecticidas/química , Aceites Volátiles/química , Floroglucinol/análogos & derivados , Aceites de Plantas/química
20.
Nutr Res Pract ; 1(4): 349-55, 2007.
Artículo en Inglés | MEDLINE | ID: mdl-20368961

RESUMEN

Stress has been known to change dietary behaviors and food intakes in individuals. The purpose of this study was to investigate the effect of stress level on the frequency and the amount of snack consumption. The high stress group (HS) showed significantly higher frequency of consumption for bread, chips, cookies, ramyeon, and frozen snacks (p<0.05) compared to low stress group (LS) with higher frequency of snack consumption (p<0.01), and increased intakes of energy, carbohydrates, and sodium from snacks (p<0.01) than LS. As the stress level became higher, the proportions of students with irregular meals, overeating, and night snacking increased (p<0.01). Also, 33.0% of the subjects answered that they consumed an increased amount of snacks when they were feeling stressed. Our results indicated that stress has negative influence on snack consumption in middle school girls.

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