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1.
Disabil Rehabil ; : 1-12, 2024 Apr 09.
Artículo en Inglés | MEDLINE | ID: mdl-38591714

RESUMEN

PURPOSE: To characterise existing knowledge about the design and learning outcomes of education and training programs for supported or shared decision making. MATERIALS AND METHODS: A scoping review was performed to identify academic and grey literature, published between January 2006 and February 2022, that reported on the design and/or learning outcomes of supported or shared decision making education or training programs. Eligible literature was mapped across domains of educational design and Kirkpatrick's hierarchy of learning effectiveness, and then qualitatively synthesised using cross-case analysis. RESULTS: A total of 33 articles were identified (n = 7 for supported decision making and n = 26 for shared decision making) that provided education or training to supporters of persons with mental illness or substance use disorders (n = 14), dementia or neurocognitive disorders (n = 6), cognitive disability (n = 5), mixed populations (n = 1), and those receiving end-of-life care (n = 7). In their design, most programs sought specific changes in practice (behaviour) via experiential learning. Reported educational outcomes also focused on supporter behaviour, with limited evidence for how changes in learner attitudes, skills, or knowledge might be contributing to changes in supporter behaviour. CONCLUSIONS: Future education and training would benefit from a closer engagement with theories of teaching and learning, particularly those oriented towards co-design.


Existing education and training programs for supported and shared decision making have a solid focus on modifying supporter behaviour through information provision, reflective practice, and modelling and coaching desired behaviour.To fully realise supported decision making, education and training programs would benefit from a focus on program co-design and working within a socio-ecological model of supported decision making.Future evaluations of supported decision making education should draw from both quantitative and qualitative approaches, with a focus on identifying the learning processes through which education influences supporter behaviour, organisational practices, and client/patient outcomes.

2.
FEBS J ; 272(8): 1886-99, 2005 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-15819883

RESUMEN

We report herein the first molecular characterization of 5'-deoxy-5'-methylthio-adenosine phosphorylase II from Sulfolobus solfataricus (SsMTAPII). The isolated gene of SsMTAPII was overexpressed in Escherichia coli BL21. Purified recombinant SsMTAPII is a homohexamer of 180 kDa with an extremely low Km (0.7 microm) for 5'-deoxy-5'-methylthioadenosine. The enzyme is highly thermophilic with an optimum temperature of 120 degrees C and extremely thermostable with an apparent Tm of 112 degrees C that increases in the presence of substrates. The enzyme is characterized by high kinetic stability and remarkable SDS resistance and is also resistant to guanidinium chloride-induced unfolding with a transition midpoint of 3.3 m after 22-h incubation. Limited proteolysis experiments indicated that the only one proteolytic cleavage site is localized in the C-terminal region and that the C-terminal peptide is necessary for the integrity of the active site. Moreover, the binding of 5'-deoxy-5'-methylthioadenosine induces a conformational transition that protected the enzyme against protease inactivation. By site-directed mutagenesis we demonstrated that Cys259, Cys261 and Cys262 play an important role in the enzyme stability since the mutants C259S/C261S and C262S show thermophilicity and thermostability features significantly lower than those of the wild-type enzyme. In order to get insight into the physiological role of SsMTAPII a comparative kinetic analysis with the homologous 5'-deoxy-5'-methylthioadenosine phosphorylase from Sulfolobus solfataricus (SsMTAP) was carried out. Finally, the alignment of the protein sequence of SsMTAPII with those of SsMTAP and human 5'-deoxy-5'-methylthioadenosine phosphorylase (hMTAP) shows several key residue changes that may account why SsMTAPII, unlike hMTAP, is able to recognize adenosine as substrate.


Asunto(s)
Purina-Nucleósido Fosforilasa/química , Purina-Nucleósido Fosforilasa/metabolismo , Sulfolobus solfataricus/enzimología , Secuencia de Aminoácidos , Clonación Molecular , Estabilidad de Enzimas/genética , Humanos , Cinética , Datos de Secuencia Molecular , Mutación/genética , Conformación Proteica , Purina-Nucleósido Fosforilasa/genética , Purina-Nucleósido Fosforilasa/aislamiento & purificación , Alineación de Secuencia , Sulfolobus solfataricus/genética , Termodinámica
3.
Proteins ; 58(4): 815-25, 2005 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-15645450

RESUMEN

S-adenosylhomocysteine hydrolase (AdoHcyHD) is an ubiquitous enzyme that catalyzes the breakdown of S-adenosylhomocysteine, a powerful inhibitor of most transmethylation reactions, to adenosine and L-homocysteine. AdoHcyHD from the hyperthermophilic archaeon Pyrococcus furiosus (PfAdoHcyHD) was cloned, expressed in Escherichia coli, and purified. The enzyme is thermoactive with an optimum temperature of 95 degrees C, and thermostable retaining 100% residual activity after 1 h at 90 degrees C and showing an apparent melting temperature of 98 degrees C. The enzyme is a homotetramer of 190 kDa and contains four cysteine residues per subunit. Thiol groups are not involved in the catalytic process whereas disulfide bond(s) could be present since incubation with 0.8 M dithiothreitol reduces enzyme activity. Multiple sequence alignment of hyperthermophilic AdoHcyHD reveals the presence of two cysteine residues in the N-terminus of the enzyme conserved only in members of Pyrococcus species, and shows that hyperthermophilic AdoHcyHD lack eight C-terminal residues, thought to be important for structural and functional properties of the eukaryotic enzyme. The homology-modeled structure of PfAdoHcyHD shows that Trp220, Tyr181, Tyr184, and Leu185 of each subunit and Ile244 from a different subunit form a network of hydrophobic and aromatic interactions in the central channel formed at the subunits interface. These contacts partially replace the interactions of the C-terminal tail of the eukaryotic enzyme required for tetramer stability. Moreover, Cys221 and Lys245 substitute for Thr430 and Lys426, respectively, of the human enzyme in NAD-binding. Interestingly, all these residues are fairly well conserved in hyperthermophilic AdoHcyHDs but not in mesophilic ones, thus suggesting a common adaptation mechanism at high temperatures.


Asunto(s)
Adenosilhomocisteinasa/química , Pyrococcus furiosus/enzimología , Adenosina/química , Secuencia de Aminoácidos , Catálisis , Clonación Molecular , Cisteína/química , Disulfuros/química , Electroforesis en Gel de Poliacrilamida , Homocisteína/química , Calor , Cinética , Lisina/química , Metilación , Modelos Moleculares , Datos de Secuencia Molecular , Plásmidos/metabolismo , Unión Proteica , Conformación Proteica , Estructura Terciaria de Proteína , Pyrococcus/metabolismo , Proteínas Recombinantes/química , Homología de Secuencia de Aminoácido , Sulfolobus solfataricus/enzimología , Temperatura , Treonina/química
4.
Eur J Biochem ; 271(23-24): 4834-44, 2004 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-15606771

RESUMEN

The extremely heat-stable 5'-methylthioadenosine phosphorylase from the hyperthermophilic archaeon Pyrococcus furiosus was cloned, expressed to high levels in Escherichia coli, and purified to homogeneity by heat precipitation and affinity chromatography. The recombinant enzyme was subjected to a kinetic analysis including initial velocity and product inhibition studies. The reaction follows an ordered Bi-Bi mechanism and phosphate binding precedes nucleoside binding in the phosphorolytic direction. 5'-Methylthioadenosine phosphorylase from Pyrococcus furiosus is a hexameric protein with five cysteine residues per subunit. Analysis of the fragments obtained after digestion of the protein alkylated without previous reduction identified two intrasubunit disulfide bridges. The enzyme is very resistant to chemical denaturation and the transition midpoint for guanidinium chloride-induced unfolding was determined to be 3.0 M after 22 h incubation. This value decreases to 2.0 M in the presence of 30 mM dithiothreitol, furnishing evidence that disulfide bonds are needed for protein stability. The guanidinium chloride-induced unfolding is completely reversible as demonstrated by the analysis of the refolding process by activity assays, fluorescence measurements and SDS/PAGE. The finding of multiple disulfide bridges in 5'-methylthioadenosine phosphorylase from Pyrococcus furiosus argues strongly that disulfide bond formation may be a significant molecular strategy for stabilizing intracellular hyperthermophilic proteins.


Asunto(s)
Disulfuros/química , Purina-Nucleósido Fosforilasa/aislamiento & purificación , Pyrococcus furiosus/enzimología , Secuencia de Aminoácidos , Clonación Molecular , Estabilidad de Enzimas , Guanidina , Datos de Secuencia Molecular , Desnaturalización Proteica , Pliegue de Proteína , Purina-Nucleósido Fosforilasa/química , Purina-Nucleósido Fosforilasa/genética , Purina-Nucleósido Fosforilasa/metabolismo , Homología de Secuencia de Aminoácido , Espectrometría de Fluorescencia
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