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1.
Nurs Open ; 9(6): 2532-2551, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-34191399

RESUMO

AIM: To explore the experiences and perspectives of the combined use of continuous subcutaneous insulin infusion (CSII) and continuous glucose monitoring (CGM) on parents of children with TIDM on their daily life. DESIGN: A systematic review and meta-synthesis of qualitative studies. METHODS: A systematic literature search of English studies published in seven databases between 2006-2021: CINAHL, MEDLINE, EMBASE, PubMed, PsycINFO, Cochrane Library and Scopus. All included studies underwent the process of thematic interpretive integration by the author team. RESULTS: Nine studies met the inclusion criteria. Six derived themes were generated which contained interacting with devices, interacting with glycaemic information, improving quality of life for parents of children with T1DM, burden of living with CSII therapy and CGM, impact on the parent-child relationship, requirement and expectation to advanced diabetes technology. Advanced diabetes technologies affect physical, emotional and relationship between the daily life of parents and their children with T1DM.


Assuntos
Diabetes Mellitus Tipo 1 , Humanos , Diabetes Mellitus Tipo 1/tratamento farmacológico , Automonitorização da Glicemia , Glicemia , Qualidade de Vida , Insulina , Pais
2.
Nucleus (La Habana) ; (64): 37-41, July.-Dec. 2018. graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1002726

RESUMO

Summary The E36 experiment has been carried out at J-PARC to search for Lepton Universality violation in the kaon two body decays K l2 . A precise value of the decay width ratio R K = Γ ( K e 2 ) = Γ ( K μ 2 ) will be extracted and compared with the standard model (SM) value. Any sizable difference would suggest new physics beyond the SM. Simultaneously, E36 is sensitive to light U(1) gauge bosons which could be associated with dark matter or explain established muon-related anomalies (g-2). The experiment as well as the status of the analysis will be presented.


Resumen El experimento E36 se ha llevado a cabo en J-PARC para buscar anomalías a la universalidad leptónica en las desintegraciones en dos leptones del kaón K l2 . Se extraerá un valor preciso de la fracción de anchos de desintegración R K = Γ ( K e 2 ) = Γ ( K μ 2 ) y se comparará con el valor del modelo estándar (SM). Cualquier diferencia considerable sugeriría una nueva física más allá del SM. Simultáneamente, E36 es sensible a los bosones de gauge ligeros U(1) que podrían estar asociados con la materia oscura o explicar anomalías relacionadas con el muón (g-2). El experimento y el estado del análisis serán presentados.

3.
Phys Chem Chem Phys ; 15(34): 14290-4, 2013 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-23881181

RESUMO

Microbial electrosynthesis cells (MECs) are devices wherein microorganisms can electrochemically interact with electrodes, directly donating or accepting electrons from electrode surfaces. Here, we developed a novel cathode by using nickel nanowires anchored to graphite for the improvement of microbial-catalyzed reduction in MEC cathode chamber. This porous nickel-nanowire-network-coated graphite electrode increased the interfacial area and interfacial interactions between the cathode surface and the microbial biofilm. A 2.3 fold increase in bio-reduction rate over the untreated graphite was observed. Around 282 mM day(-1) m(-2) of acetate resulting from the bio-reduction of carbon dioxide by Sporomusa was produced with 82 ± 14% of the electrons consumed being recovered in acetate.


Assuntos
Fontes de Energia Bioelétrica , Veillonellaceae/fisiologia , Biocatálise , Fontes de Energia Bioelétrica/microbiologia , Biofilmes , Dióxido de Carbono/química , Técnicas Eletroquímicas , Eletrodos , Grafite , Nanofios/química , Nanofios/ultraestrutura , Níquel/química , Oxirredução
4.
Nat Struct Mol Biol ; 19(12): 1316-23, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23104056

RESUMO

Ribosome synthesis involves dynamic association of ribosome-biogenesis factors with evolving preribosomal particles. Rio2 is an atypical protein kinase required for pre-40S subunit maturation. We report the crystal structure of eukaryotic Rio2-ATP-Mg(2+) complex. The active site contains ADP-Mg(2+) and a phosphoaspartate intermediate typically found in Na(+), K(+) and Ca(2+) ATPases but not protein kinases. Consistent with this finding, ctRio2 exhibits a robust ATPase activity in vitro. In vivo, Rio2 docks on the ribosome, with its active site occluded and its flexible loop positioned to interact with the pre-40S subunit. Moreover, Rio2 catalytic activity is required for its dissociation from the ribosome, a necessary step in pre-40S maturation. We propose that phosphoryl transfer from ATP to Asp257 in Rio2's active site and subsequent hydrolysis of the aspartylphosphate could be a trigger to power late cytoplasmic 40S subunit biogenesis.


Assuntos
Adenosina Trifosfatases/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Ribossomos , Humanos , Modelos Moleculares
5.
Langmuir ; 27(20): 12443-50, 2011 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-21882880

RESUMO

In situ neutron reflectivity was used to study thermally induced structural changes of the lamellae-forming polystyrene-block-poly(2-vinylpyridine) (PS-b-P2VP) block copolymer thin films floating on the surface of an ionic liquid (IL). The IL, 1-butyl-3-methylimidazolium trifluoromethanesulfonate, is a nonsolvent for PS and a temperature-tunable solvent for P2VP, and, as such, micellization can be induced at the air-IL interface by changing the temperature. Transmission electron microscopy and scanning force microscopy were used to investigate the resultant morphologies of the micellar films. It was found that highly ordered nanostructures consisting of spherical micelles with a PS core surrounded by a P2VP corona were produced. In addition, bilayer films of PS homopolymer on top of a PS-b-P2VP layer also underwent micellization with increasing temperature but the micellization was strongly dependent on the thickness of the PS and PS-b-P2VP layers.


Assuntos
Líquidos Iônicos/química , Micelas , Poliestirenos/química , Polivinil/química , Microscopia Eletrônica de Varredura , Modelos Moleculares , Propriedades de Superfície , Temperatura
6.
Langmuir ; 26(22): 17126-32, 2010 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-20973541

RESUMO

Highly ordered and stable micelles formed from both symmetric and asymmetric block copolymers of polystyrene-block-poly(2-vinylpyridine) (PS-b-P2VP) at the Si-ionic liquid (IL) interface have been investigated by scanning force microscopy (SFM) and transmission electron microscopy (TEM). The 1-butyl-3-methylimidazolium trifluoromethanesulfonate IL, a selective and temperature-tunable solvent for the P2VP block, was used and gave rise to block copolymer micelles having different morphologies that strongly depended on the annealing temperature. The effects of film thickness, molecular weight of block copolymers, and experimental conditions, such as preannealing, rinsing, and substrate properties, on the morphologies of block copolymer micelles were also studied. In addition, spherical micelles consisting of PS core and P2VP shell could also be obtained by core-corona inversion by annealing the as-coated micellar film in the IL at high temperatures. The possible mechanism for micelle formation is discussed.

7.
J Phys Chem B ; 111(51): 14378-86, 2007 Dec 27.
Artigo em Inglês | MEDLINE | ID: mdl-18052272

RESUMO

Films constructed layer-by-layer on electrodes with architecture {protein/hyaluronic acid (HA)}n containing myoglobin (Mb) or horseradish peroxidase (HRP) were protected against protein damage by H2O2 by using outer catalase layers. Peroxidase activity for substrate oxidation requires activation by H2O2, but {protein/HA}n films without outer catalase layers are damaged slowly and irreversibly by H2O2. The rate and extent of damage were decreased dramatically by adding outer catalase layers to decompose H2O2. Comparative studies suggest that protection results from catalase decomposing a fraction of the H2O2 as it enters the film, rather than by an in-film diffusion barrier. The outer catalase layers controlled the rate of H2O2 entry into inner regions of the film, and they biased the system to favor electrocatalytic peroxide reduction over enzyme damage. Catalase-protected {protein/HA}n films had an increased linear concentration range for H2O2 detection. This approach offers an effective way to protect biosensors from damage by H2O2.


Assuntos
Técnicas Biossensoriais/métodos , Catalase/química , Eletrólitos/química , Enzimas Imobilizadas/química , Peroxidase do Rábano Silvestre/química , Catalase/metabolismo , Catálise , Eletroquímica , Enzimas Imobilizadas/metabolismo , Peroxidase do Rábano Silvestre/metabolismo , Ácido Hialurônico/química , Ácido Hialurônico/metabolismo , Peróxido de Hidrogênio/química , Mioglobina/química , Mioglobina/metabolismo , Oxirredução , Sensibilidade e Especificidade , Propriedades de Superfície
8.
J Phys Chem B ; 111(8): 1984-93, 2007 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-17274644

RESUMO

The ionic strength in supporting electrolyte solution had a significant influence on the electrochemical and electrocatalytic behaviors of myoglobin (Mb) in {HA/Mb}n films, which were assembled layer-by-layer on pyrolytic graphite (PG) electrodes with oppositely charged hyaluronic acid (HA) and Mb. The results of cyclic voltammetry (CV), quartz crystal microbalance (QCM), scanning electron microscopy (SEM), rotating disk voltammetry (RDV), and electrochemical impedance spectroscopy (EIS) showed that after incubation with testing solution at high concentration of salt (CKCl), the {HA/Mb}n films swelled and the film permeability was enhanced, suggesting that the external salt ions and accompanied water molecules in the exposure solution are incorporated into the films. Systematic investigation of the type and size effect of counterions in supporting electrolyte solution on the electrochemical responses for the {HA/Mb}n films and the positive shift of the formal potential (E degrees ') with CKCl suggest that it is cationic rather than anionic counterions that control the electrode process of {HA/Mb}n films at PG electrodes with electron hopping mechanism. The salt-induced swelling of {HA/Mb}n films facilitated the transportation of counterions, and then accelerated the electron transfer of Mb in the films with the underlying electrodes, making the film electrodes show better CV responses. The comparative study showed that only Mb layer-by-layer films assembled with "soft" and flexible polyions could demonstrate the salt-induced effect and that the {HA/Mb}n films showed better swelling capability than {PSS/Mb}n films (PSS = poly(styrenesulfonate)) due to the unique character of HA.


Assuntos
Ácido Hialurônico/química , Mioglobina/química , Eletroquímica , Eletrodos , Grafite/química , Nanoestruturas/química , Permeabilidade , Sais/química , Cloreto de Sódio/química
9.
J Phys Chem B ; 110(47): 23710-8, 2006 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-17125331

RESUMO

When {CS/HA}n layer-by-layer films assembled by oppositely charged chitosan (CS) and hyaluronic acid (HA) were immersed in myoglobin (Mb) solution at pH 5.0, Mb was gradually loaded into the {CS/HA}n films, designated as {CS/HA}n-Mb. The cyclic voltammetric (CV) peak pair of Mb FeIII/FeII redox couple for {CS/HA}n-Mb films on pyrolytic graphite (PG) electrodes was used to investigate the loading behavior of {CS/HA}n films toward Mb. The various influencing factors, such as the number of bilayers (n), the pH of Mb loading solution, and the ionic strength of solution, were investigated by different electrochemical methods and other techniques. The results showed that the main driving force for the bulk loading of Mb was most probably the electrostatic interaction between oppositely charged Mb in solution and HA in the films, while other interactions such as hydrogen bonding and hydrophobic interaction may also play an important role. Other polyelectrolyte multilayer (PEM) films with different components were compared with {CS/HA}n films in permeability and Mb loading, and electroactive probes with different size and surface charge were compared in their incorporation into PEM films. The results suggest that due to the unique structure of CS and HA, {CS/HA}n films with relatively low charge density are packed more loosely and more easily swelled by water, and have better permeability, which may lead to the higher loading amount and shorter loading time for Mb. The protein-loaded PEM films provide a new route to immobilize redox proteins on electrodes and realize the direct electrochemistry of the proteins.


Assuntos
Quitosana/química , Ácido Hialurônico/química , Mioglobina/química , Nanoestruturas/química , Adsorção , Eletroquímica , Eletrodos , Eletrólitos , Grafite/química , Ligação de Hidrogênio , Concentração de Íons de Hidrogênio , Interações Hidrofóbicas e Hidrofílicas , Conformação Proteica , Soluções/química , Espectrofotometria Ultravioleta , Eletricidade Estática
10.
J Phys Chem B ; 110(5): 2171-9, 2006 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-16471801

RESUMO

Alternate adsorption of oppositely charged myoglobin (Mb) and gold nanoparticles with different sizes were used to assemble {Au/Mb}n layer-by-layer films on solid surfaces by electrostatic interaction between them. The direct electrochemistry of Mb was realized in {Au/Mb}n films at pyrolytic graphite (PG) electrodes, showing a pair of well-defined, nearly reversible cyclic voltammetry (CV) peaks for the Mb heme FeIII/FeII redox couple. Quartz crystal microbalance (QCM), electrochemical impedance spectroscopy (EIS), and CV were used to monitor or confirm the growth of the films. Compared with other Mb layer-by-layer films with nonconductive nanoparticles or polyions, {Au/Mb}n films showed much improved properties, such as smaller electron-transfer resistance (Rct) measured by EIS with Fe(CN)3-/4- redox probe, higher maximum surface concentration of electroactive Mb (Gamma*max), and better electrocatalytic activity toward reduction of O2 and H2O2, mainly because of the good conductivity of Au nanoparticles. Because of the high biocompatibility of Au nanoparticles, adsorbed Mb in the films retained its near native structure and biocatalytic activity. The size effect of Au nanoparticles on the electrochemical and electrocatalytic activity of Mb in {Au/Mb}n films was investigated, demonstrating that the {Au/Mb}n films assembled with smaller-sized Au nanoparticles have smaller Rct, higher Gamma*max, and better biocatalytic reactivity than those with larger size.


Assuntos
Ouro/química , Heme/química , Mioglobina/química , Nanoestruturas/química , Adsorção , Carbono/química , Catálise , Cristalização , Impedância Elétrica , Eletroquímica , Eletrodos , Ferricianetos/química , Peróxido de Hidrogênio/química , Oxirredução , Oxigênio/química , Tamanho da Partícula , Quartzo
11.
Biophys Chem ; 104(3): 623-32, 2003 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-12914908

RESUMO

The direct voltammetry and electrocatalytic properties of catalase (Cat) in polyacrylamide (PAM) hydrogel films cast on pyrolytic graphite (PG) electrodes were investigated. Cat-PAM film electrodes showed a pair of well-defined and nearly reversible cyclic voltammetry peaks for Cat Fe(III)/Fe(II) redox couples at approximately -0.46 V vs. SCE in pH 7.0 buffers. The electron transfer between catalase and PG electrodes was greatly facilitated in the microenvironment of PAM films. The apparent heterogeneous electron transfer rate constant (k(s)) and formal potential (E degrees ') were estimated by fitting square wave voltammograms with non-linear regression analysis. The formal potential of Cat Fe(III)/Fe(II) couples in PAM films had a linear relationship with pH between pH 4.0 and 9.0 with a slope of -56 mV pH(-1), suggesting that one proton is coupled with single-electron transfer for each heme group of catalase in the electrode reaction. UV-Vis absorption spectroscopy demonstrated that catalase retained a near native conformation in PAM films at medium pH. The embedded catalase in PAM films showed the electrocatalytic activity toward dioxygen and hydrogen peroxide. Possible mechanism of catalytic reduction of H(2)O(2) at Cat-PAM film electrodes was proposed.


Assuntos
Resinas Acrílicas/química , Técnicas Biossensoriais , Catalase/química , Quitina/análogos & derivados , Resinas Acrílicas/metabolismo , Animais , Carbono/química , Catalase/metabolismo , Catálise , Bovinos , Quitina/química , Quitosana , Dimiristoilfosfatidilcolina/química , Eletroquímica , Transporte de Elétrons , Hemoglobinas/química , Peroxidase do Rábano Silvestre/química , Peróxido de Hidrogênio/metabolismo , Concentração de Íons de Hidrogênio , Fígado/enzimologia , Microscopia Eletrônica de Varredura , Mioglobina/química , Oxirredução , Oxigênio/metabolismo , Compostos de Amônio Quaternário/química , Análise Espectral
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