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1.
J Neurol Sci ; 324(1-2): 100-5, 2013 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-23140806

RESUMO

UNLABELLED: The psychosocial consequences for parents of children with MS have not been studied. OBJECTIVES: to assess aspects of coping with family crisis and individual states of distress in couples with a child with MS compared to couples of healthy children. METHODS: fifteen couples with a child with MS and 29 couples with healthy children were assessed using self-administered scales on anxiety, depression, coping, marital and family aspects, quality of life and MS knowledge. RESULTS: parents of children with MS were less satisfied with their parenting role and had a lower sense of parenting competence than control parents. While their depression scores were higher than control parents, they scored within the normal range. Mothers of children with MS were more worried than fathers and were more likely to use diverse coping strategies. Less knowledge of MS was correlated with less satisfaction with the couple relationship and with the quality of communication. There was a correlation between limited knowledge about the child's illness and the overall sense of competence as a parent. CONCLUSIONS: lack of information about MS can impact family functioning, anxiety and parents' sense of competency. Parents require support in becoming more knowledgeable about MS in order to feel competent and satisfied in their role and to cope successfully.


Assuntos
Conhecimentos, Atitudes e Prática em Saúde , Esclerose Múltipla/psicologia , Pais/psicologia , Satisfação Pessoal , Adaptação Psicológica , Adolescente , Adulto , Ansiedade/psicologia , Criança , Aconselhamento , Depressão/psicologia , Características da Família , Relações Familiares , Feminino , Humanos , Masculino , Testes Neuropsicológicos , Qualidade de Vida , Fatores Socioeconômicos , Estresse Psicológico/psicologia , Inquéritos e Questionários
2.
J Pept Sci ; 11(7): 401-9, 2005 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-15635670

RESUMO

An ESR investigation of the interaction of spin-labelled penetratin with heparin, heparansulfates and several phospholipid vesicle formulations is reported. Penetratin is a 16-aa peptide corresponding to the third helix of the Antennapedia homeodomain and belonging to the cell-penetrating peptide family. The present study shows that ESR spectroscopy can provide specific and reliable information about the mechanism of interaction of penetratin with polysaccharides and lipids, at a molecular level. The study showed that: (i) heparin and heparansulfates specifically interact with spin-labelled penetratin and promote peptide aggregation and concentration on their molecular surface; (ii) penetratin does not interact with neutral lipids, whereas it enters negatively charged lipid bilayers; (iii) cholesterol plays a negative effect on the insertion of penetratin into the lipid membrane; (iv) the interaction of penetratin with lipid vesicles is strongly dependent on lipid concentration. In a low lipid regime, penetratin associates with the polar heads of phospholipids and aggregates on the membrane surface; once the lipid concentration attains a threshold, the peptide enters the lipid bilayer. This step is characterized by reduced peptide mobility and partial disaggregation.It has been shown that ESR spectroscopy is a valuable investigation tool in studies related to the still unclear mechanism of the internalization process.


Assuntos
Proteínas de Transporte/metabolismo , Heparina/metabolismo , Heparitina Sulfato/metabolismo , Fosfolipídeos/metabolismo , Proteínas de Transporte/química , Peptídeos Penetradores de Células , Colesterol/metabolismo , Espectroscopia de Ressonância de Spin Eletrônica , Heparina/química , Heparitina Sulfato/química , Ligantes , Lipossomos , Fosfolipídeos/química , Ligação Proteica
3.
J Chromatogr A ; 944(1-2): 141-8, 2002 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-11831749

RESUMO

In this paper we report the scale-up of the purification of poly(ethylene glycol) (PEG) derivatives of the growth hormone-releasing factor 1-29, from laboratory scale (100 mg of bulk starting material) to larger scale (3 g of bulk), through the use of a cation-exchange TSK-SP-5PW chromatographic column. A one-step purification process capable of purifying large amounts of mono-PEGylated GRF species from the crude reaction mixture was developed. A simple, straightforward stepwise gradient elution separation was developed at laboratory scale and then scaled up with a larger column packed with a chromatographic resin with the same chemistry which maintained the laboratory-scale separation profile. Active material recovery and material purity remained constant through the scale-up from the 13-microm stationary phase to the 25-microm larger column. Overall, the gram GRF equivalent/batch process scale showed to be quite reproducible, and could be considered as a good platform for scale up to production scale.


Assuntos
Cromatografia por Troca Iônica/métodos , Hormônio Liberador de Hormônio do Crescimento/isolamento & purificação , Fragmentos de Peptídeos/isolamento & purificação , Polietilenoglicóis/química , Resinas de Troca de Cátion , Hormônio Liberador de Hormônio do Crescimento/química , Fragmentos de Peptídeos/química , Reprodutibilidade dos Testes
4.
J Mass Spectrom ; 35(2): 210-7, 2000 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10679983

RESUMO

The extent and distribution of N-glycosylation and the nature of most of the disulfide bond linkages were determined for bovine lactoperoxidase through proteolytic and glycolytic digestions combined with matrix-assisted laser desorption/ionization mass spectrometric analysis. In addition, 98% of the primary sequence of the protein was confirmed. All five of the asparagines present in sequons were found to be glycosylated, predominantly by high mannose and complex structures. Six disulfide bonds were assigned, including Cys 32-Cys 45, Cys 146-Cys 156, Cys 150-Cys 174, Cys 254-Cys 265, Cys 473-Cys 530 and Cys 571-Cys 596.


Assuntos
Carboidratos/análise , Dissulfetos/análise , Lactoperoxidase/análise , Sequência de Aminoácidos , Animais , Bovinos , Glicopeptídeos/química , Glicosilação , Hidrólise , Indicadores e Reagentes , Dados de Sequência Molecular , Conformação Proteica , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Tripsina
5.
J Biol Inorg Chem ; 4(1): 12-20, 1999 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10499098

RESUMO

Binding affinities to lactoperoxidase (LPO) of a homologous series of substituted catechol(amine)s [such as catechol, 4-methylcatechol, 3,4-dihydroxybenzoic acid, 3,4-dihydroxyphenylacetic acid, 3-(3,4-dihydroxyphenyl)propionic acid; dopamine, noradrenaline, adrenaline; L-3,4-dihydroxyphenylalanine] were studied by UV-visible spectroscopy and docking simulations. Dissociation constant (Kd) values were calculated by direct fitting of the experimental data and fall in a range of 3-95 mM. Thermodynamic parameters are comparable with those reported for the interaction of LPO with p-substituted phenols, suggesting a similar general mode of binding. Furthermore, the relative contributions to binding energy, described by the unimolecular constant Ku, show that interaction between protein and ligands originates from a relatively large number of groups. Docking and molecular dynamics simulations, in agreement with experimental evidence, predict that the substrate is localized into the access channel in the vicinity of heme distal pocket. This channel is characterized by a hydrophobic patch (six Phe residues) and by a charged contribution (two Glu and one His residues). All of the substrates, except caffeic acid, may approach the protein active site. Positively charged Arg372 acts as a gate above the heme distal pocket and seems to address substrate orientation in relation to the side-chain terminal group.


Assuntos
Catecolaminas/química , Catecolaminas/metabolismo , Lactoperoxidase/química , Lactoperoxidase/metabolismo , Ácido 3,4-Di-Hidroxifenilacético/química , Ácido 3,4-Di-Hidroxifenilacético/metabolismo , Animais , Ácidos Cafeicos/química , Ácidos Cafeicos/metabolismo , Domínio Catalítico , Bovinos , Simulação por Computador , Di-Hidroxifenilalanina/química , Di-Hidroxifenilalanina/metabolismo , Dopamina/química , Dopamina/metabolismo , Concentração de Íons de Hidrogênio , Hidroxibenzoatos/química , Hidroxibenzoatos/metabolismo , Modelos Moleculares , Norepinefrina/química , Norepinefrina/metabolismo , Conformação Proteica , Espectrofotometria Ultravioleta , Termodinâmica
6.
J Inorg Biochem ; 68(1): 17-26, 1997 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-9379177

RESUMO

The interaction of several inorganic species (SCN-, I-, Br-, Cl-, F-, NO2-, N3-, CN-) with bovine lactoperoxidase was investigated through kinetic and binding studies by using UV-Vis spectroscopy. The above ligands form 1:1 complexes with the protein and can be assigned to three different groups, on the basis of the dissociation constant values (KD) of the adducts: (1) SCN-, I-, Br-, and Cl- (KD increases along the series); (2) F- (which shows a singular behavior); (3) NO2-, N3-, and CN- (that bind at the iron site). KD values for the LPO/SCN- adduct appeared to be modified in the presence of other inorganic species; a strong competition between this substrate and all other anions (with the exception of F-) was evidentiated. Binding investigations on the natural substrates SCN- and I-, at varying pH and temperature, showed that their interaction with lactoperoxidase involves the protonation of a common site in proximity of the iron (possibly distal histidine). Michaelis-Menten constants for SCN-, I-, and Br- followed roughly the same trend as KD; KM for hydrogen peroxide is strongly dependent on the cosubstrate. Computer-assisted docking simulations showed that all ligands can penetrate inside the heme pocket.


Assuntos
Ânions/metabolismo , Lactoperoxidase/química , Lactoperoxidase/metabolismo , Análise Espectral/métodos , Animais , Ânions/química , Sítios de Ligação , Ligação Competitiva , Brometos/química , Brometos/metabolismo , Bovinos , Simulação por Computador , Concentração de Íons de Hidrogênio , Iodetos/química , Iodetos/metabolismo , Cinética , Modelos Moleculares , Conformação Proteica , Temperatura , Tiocianatos/química , Tiocianatos/metabolismo
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