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1.
J Intellect Disabil Res ; 68(6): 564-572, 2024 06.
Artículo en Inglés | MEDLINE | ID: mdl-38413188

RESUMEN

BACKGROUND: Active Support is a person-centred practice that enables people with intellectual disabilities (IDs) to engage in meaningful activities and social interactions. The Active Support Measure (ASM) is an observational tool designed to measure the quality of support that people with IDs living in supported accommodation services receive from staff. The aim of the study was to explore the underlying constructs of the ASM. METHODS: Multilevel exploratory factor analysis was conducted on ASM data (n = 884 people with IDs across 236 accommodation services) collected during a longitudinal study of Active Support in Australian accommodation services. RESULTS: Multilevel exploratory factor analysis indicated that 12 of the ASM's 15 items loaded on two factors, named Supporting Engagement in Activities and Interacting with the Person. CONCLUSIONS: The 12-item ASM measures two dimensions of the quality of staff support. Both technical and interpersonal skills comprise good Active Support.


Asunto(s)
Discapacidad Intelectual , Humanos , Adulto , Masculino , Femenino , Análisis Factorial , Persona de Mediana Edad , Estudios Longitudinales , Australia , Adulto Joven , Adolescente , Atención Dirigida al Paciente/normas , Apoyo Social , Interacción Social
2.
J Autism Dev Disord ; 53(5): 1834-1849, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-35239083

RESUMEN

Parents of children with autism spectrum disorder and other disabilities report high levels of distress, but systematically evaluated interventions are few. This study aimed to evaluate the feasibility of a novel, manualized Acceptance and Commitment Therapy group intervention (Navigator ACT) in a sample of 94 parents of children with disabilities. Feasibility was measured by treatment completion, credibility, and satisfaction, and preliminary outcomes by using self-rating scales administered at the baseline, post-intervention, and follow-up. The results imply the intervention is feasible in the context of Swedish outpatient habilitation services. A preliminary analysis of the outcome measures suggests that parents experienced significant improvements in well-being. The results indicate that the treatment is feasible and should be evaluated in a randomized controlled trial.


Asunto(s)
Terapia de Aceptación y Compromiso , Trastorno del Espectro Autista , Niños con Discapacidad , Niño , Humanos , Trastorno del Espectro Autista/terapia , Estudios de Factibilidad , Padres
3.
J Intellect Disabil Res ; 61(2): 155-167, 2017 02.
Artículo en Inglés | MEDLINE | ID: mdl-27283246

RESUMEN

BACKGROUND: The present study aimed to explore the applicability of the attribution model to social workers' attributions towards clients with dual diagnosis of intellectual disability and psychiatric illness. Specifically, the study examined the relations between social workers' attribution of responsibility, causality, stereotypes of dangerousness, their emotional reactions and behavioural reactions towards clients with dual diagnosis. METHOD: Social workers (N = 279) completed questionnaires measuring attributions of responsibility, causation and dangerousness, and reported on their emotional and behavioural reactions to clients diagnosed with DD. RESULTS: Most social workers reported high levels of helping behaviours. The strongest predictor of discriminatory behaviours was the stereotype of dangerousness. Social workers who reported feeling less anger and more pity towards clients with DD tended to report higher levels of helping behaviour. But contrary to attribution theory, fear and anger did not predict discriminatory behaviours. CONCLUSION: The results are discussed in relation to the core values of social work and to professional identity.


Asunto(s)
Actitud del Personal de Salud , Conducta de Ayuda , Discapacidad Intelectual/psicología , Trastornos Mentales/psicología , Trabajadores Sociales/psicología , Estereotipo , Adulto , Comorbilidad , Femenino , Humanos , Discapacidad Intelectual/epidemiología , Masculino , Trastornos Mentales/epidemiología , Persona de Mediana Edad
4.
Allergy ; 68(5): 585-92, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23464525

RESUMEN

BACKGROUND: Allergy to dog (Canis familiaris) is a worldwide common cause of asthma and allergic rhinitis. However, dander extract in routine diagnostics is not an optimal predictor of IgE-mediated dog allergy. Our objective was to evaluate saliva as an allergen source for improved diagnostics of allergy to dog. METHODS: IgE-binding proteins in dog saliva and dander extract were analysed by immunoblot and mass spectrometry (LC-MS/MS) using pooled or individual sera from dog-allergic patients (n = 13). Sera from 59 patients IgE positive to dander and 55 patients IgE negative to dander but with symptoms to dog were analysed for IgE against saliva and dander by ELISA. Basophil stimulation with dog saliva and dander extract was measured by flow cytometry among three dog-allergic patients. Additionally, IgE-binding protein profiles of saliva from different breeds were investigated by immunoblot. RESULTS: Greater number and diversity of IgE-binding proteins was found in saliva compared to dander extract and varied among dog breeds. In saliva, Can f 1, 2, 3 and 6 were identified but also four new saliva allergen candidates. The majority of the 59 dog dander-positive sera (n = 44) were IgE positive to dog saliva. Among patients IgE negative to dander, but with symptoms to dog, 20% were IgE positive to saliva. The biological activity of saliva was confirmed by basophil degranulation. CONCLUSIONS: Dog saliva is an allergen source for improved diagnostics of dog allergy. The IgE-binding protein profile of saliva from different dogs varies.


Asunto(s)
Alérgenos/inmunología , Saliva/inmunología , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Alérgenos/química , Alérgenos/metabolismo , Animales , Basófilos/inmunología , Niño , Preescolar , Perros , Ensayo de Inmunoadsorción Enzimática , Femenino , Humanos , Hipersensibilidad/sangre , Hipersensibilidad/diagnóstico , Hipersensibilidad/inmunología , Inmunoglobulina E/sangre , Inmunoglobulina E/inmunología , Inmunoglobulina E/metabolismo , Lactante , Masculino , Persona de Mediana Edad , Unión Proteica , Saliva/química , Proteínas y Péptidos Salivales/inmunología , Proteínas y Péptidos Salivales/metabolismo , Espectrometría de Masas en Tándem , Adulto Joven
6.
Undersea Hyperb Med ; 37(1): 35-48, 2010.
Artículo en Inglés | MEDLINE | ID: mdl-20369651

RESUMEN

This report describes how 27 patients with severe traumatic brain injury were safely treated, monitored and managed in a monoplace chamber that was compressed with air to 1.5 atmospheres absolute (152 kPa). A total of 75 hyperbaric oxygen treatments were delivered using the monoplace system described, with all patients receiving 100% oxygen via mechanical ventilation. Specific pieces of equipment, components and features were selected, and modifications were interfaced to safely and effectively treat these critically ill patients in a monoplace chamber. Patient monitoring included cardiovascular and ventilatory parameters as well as intracranial pressure, brain tissue oxygen levels, brain temperature and cerebral microdialysis. The chamber and all the supporting equipment for ventilating, monitoring and managing the patient functioned well.


Asunto(s)
Cámaras de Exposición Atmosférica , Lesiones Encefálicas/terapia , Oxigenoterapia Hiperbárica/instrumentación , Protocolos Clínicos , Diseño de Equipo , Humanos , Oxigenoterapia Hiperbárica/efectos adversos , Oxigenoterapia Hiperbárica/métodos
7.
Cell Mol Life Sci ; 65(24): 3961-70, 2008 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-19011745

RESUMEN

Zinc plays an important role in the structure and function of many enzymes, including alcohol dehydrogenases (ADHs) of the MDR type (mediumchain dehydrogenases/reductases). Active site zinc participates in catalytic events, and structural site zinc maintains structural stability. MDR-types of ADHs have both of these zinc sites but with some variation in ligands and spacing. The catalytic zinc sites involve three residues with different spacings from two separate protein segments, while the structural zinc sites involve four residues and cover a local segment of the protein chain (Cys97-Cys111 in horse liver class I ADH). This review summarizes properties of both ADH zinc sites, and relates them to zinc sites of proteins in general. In addition, it highlights a separate study of zinc binding peptide variants of the horse liver ADH structural zinc site. The results show that zinc coordination of the free peptide differs markedly from that of the enzyme (one His / three Cys versus four Cys), suggesting that the protein zinc site is in an energetically strained conformation relative to that of the peptide. This finding is a characteristic of an entatic state, implying a functional nature for this zinc site.


Asunto(s)
Alcohol Deshidrogenasa/química , Alcohol Deshidrogenasa/metabolismo , Familia de Multigenes , Zinc/metabolismo , Secuencia de Aminoácidos , Animales , Catálisis , Dominio Catalítico , Humanos , Datos de Secuencia Molecular , Péptidos/química , Péptidos/metabolismo
8.
Cell Mol Life Sci ; 65(24): 4019-27, 2008 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-18850316

RESUMEN

Zinc binding to the peptide replica and analogs to residues 93-115 of horse liver alcohol dehydrogenase (ADH) was examined by competition of the peptides and the chromophoric chelator 4-(2- pyridylazo)resorcinol for zinc and X-ray absorption fine structure analysis of the zinc ligands. In the enzyme, zinc is coordinated by four Cys residues. In the peptide replica, zinc is bound to three Cys and one His residue. A four-Cys zinc coordination is observed only when His is removed, leading to increased zinc stability. ADH crystal structures reveal that the epsilon-amino group of the conserved residue Lys323 is within H-bond distance of the backbone amide oxygens of residues 103, 105 and 108, likely stabilizing the zinc coordination in the enzyme. The peptide data thus indicate structural strain and increased energy in the zinc-binding site in the protein, characteristic of an entatic state, implying a functional nature for this zinc site.


Asunto(s)
Alcohol Deshidrogenasa/química , Alcohol Deshidrogenasa/metabolismo , Péptidos/metabolismo , Zinc/metabolismo , Secuencias de Aminoácidos , Secuencia de Aminoácidos , Animales , Catálisis , Dominio Catalítico , Cromatografía en Gel , Análisis de Fourier , Caballos , Cinética , Ligandos , Modelos Moleculares , Datos de Secuencia Molecular , Péptidos/química , Volumetría
9.
Cell Mol Life Sci ; 64(14): 1870-80, 2007 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-17593323

RESUMEN

Proteolytic cleavage of insulin-like growth factor (IGF) binding protein (IGFBP)-3 during pregnancy is likely to have both IGF-dependent and -independent effects on maternal, placental and fetal growth and metabolism. A 30-kDa proteolytic IGFBP-3 fragment was isolated from third trimester pregnancy human serum and identified by N- and C-terminal amino acid sequence analysis and mass spectrometry to correspond to residues 1-212 of the parent protein. This fragment is the dominating IGFBP-3 immunoreactive species in pregnancy serum. The 30-kDa fragment was also detected in serum of non-pregnant women where it coexists with intact IGFBP-3. Using biosensor technology, (1-212)IGFBP-3 was found to have 11-fold lower affinity for IGF-I compared to intact IGFBP-3, while a 4-fold decrease in affinity was found for IGF-II. Tests with des(1-3)IGF-I suggest fast binding of IGF-I to the N-terminal region of IGFBP-3 and similar affinity to a slow binding site in the C-terminal region.


Asunto(s)
Proteínas de Unión a Factor de Crecimiento Similar a la Insulina/sangre , Factor II del Crecimiento Similar a la Insulina/metabolismo , Fragmentos de Péptidos/sangre , Embarazo/sangre , Secuencia de Aminoácidos , Sitios de Unión , Femenino , Humanos , Proteína 3 de Unión a Factor de Crecimiento Similar a la Insulina , Proteínas de Unión a Factor de Crecimiento Similar a la Insulina/química , Proteínas de Unión a Factor de Crecimiento Similar a la Insulina/metabolismo , Factor I del Crecimiento Similar a la Insulina/metabolismo , Cinética , Datos de Secuencia Molecular , Fragmentos de Péptidos/química , Fragmentos de Péptidos/metabolismo , Análisis de Secuencia de Proteína
10.
Anal Chim Acta ; 583(2): 310-8, 2007 Feb 05.
Artículo en Inglés | MEDLINE | ID: mdl-17386561

RESUMEN

Different analytical approaches for origin differentiation between vendace and whitefish caviars from brackish- and freshwaters were tested using inductively coupled plasma double focusing sector field mass spectrometry (ICP-SFMS) and multi-collector inductively coupled plasma mass spectrometry (MC-ICP-MS). These approaches involve identifying differences in elemental concentrations or sample-specific isotopic composition (Sr and Os) variations. Concentrations of 72 elements were determined by ICP-SFMS following microwave-assisted digestion in vendace and whitefish caviar samples from Sweden (from both brackish and freshwater), Finland and USA, as well as in unprocessed vendace roe and salt used in caviar production. This data set allows identification of elements whose contents in caviar can be affected by salt addition as well as by contamination during production and packaging. Long-term method reproducibility was assessed for all analytes based on replicate caviar preparations/analyses and variations in element concentrations in caviar from different harvests were evaluated. The greatest utility for differentiation was demonstrated for elements with varying concentrations between brackish and freshwaters (e.g. As, Br, Sr). Elemental ratios, specifically Sr/Ca, Sr/Mg and Sr/Ba, are especially useful for authentication of vendace caviar processed from brackish water roe, due to the significant differences between caviar from different sources, limited between-harvest variations and relatively high concentrations in samples, allowing precise determination by modern analytical instrumentation. Variations in the 87Sr/86Sr ratio for vendace caviar from different harvests (on the order of 0.05-0.1%) is at least 10-fold less than differences between caviar processed from brackish and freshwater roe. Hence, Sr isotope ratio measurements (either by ICP-SFMS or by MC-ICP-MS) have great potential for origin differentiation. On the contrary, it was impossible to differentiate between Swedish caviar processed from brackish water roe and Finnish freshwater caviar based solely on 187Os/188Os ratios.


Asunto(s)
Huevos/análisis , Análisis de los Alimentos/métodos , Salmonidae , Animales , Productos Pesqueros/análisis , Agua Dulce/análisis , Espectrometría de Masas/métodos , Suecia
11.
Cell Mol Life Sci ; 62(15): 1772-8, 2005 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-16003487

RESUMEN

Proinsulin C-peptide influences a number of physiological parameters in addition to its well-established role in the parent proinsulin molecule. It is of interest as a candidate for future co-replacement therapy with insulin for patients with diabetes mellitus type 1, but specific receptors have not been identified and additional correlation with functional effects is desirable. Based on comparisons of 22 mammalian proinsulin variants, we have constructed analogues for activity studies, choosing phosphorylation of mitogen-activated protein kinases (MAPKs) in Swiss 3T3 fibroblasts for functional measurements. In this manner, we find that effective phosphorylation of MAPKs is promoted by the presence of conserved glutamic acid residues at positions 3, 11 and 27 of C-peptide and by the presence of helix-promoting residues in the N-terminal segment. Previous findings have ascribed functional roles to the C-terminal pentapeptide segment, and all results combined therefore now show the importance of different segments, suggesting that C-peptide interactions are complex or multiple.


Asunto(s)
Péptido C/química , Secuencia de Aminoácidos , Animales , Péptido C/metabolismo , Secuencia Conservada , Quinasas MAP Reguladas por Señal Extracelular/metabolismo , Ácido Glutámico/química , Ratones , Datos de Secuencia Molecular , Fosforilación , Estructura Secundaria de Proteína , Alineación de Secuencia , Células 3T3 Swiss
12.
Cell Mol Life Sci ; 61(23): 2979-82, 2004 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-15583859

RESUMEN

Degradation of proinsulin C-peptide in mouse kidney and human placenta extracts was studied using reverse-phase high-performance liquid chromatography and nano-electrospray mass spectrometry. In total, 15 proteolytic cleavage sites were identified in human and mouse C-peptides. Early sites included the peptide bonds N-terminal of Val/Leu10, Leu12, Leu21, Leu24 and Leu26 in different combinations for the two tissues and two peptides. Notably, these cleavages were N-terminal of a hydrophobic residue, and all but one N-terminal of Leu. A late degradation product of the human peptide detected in the kidney extract was the C-terminal hexapeptide, containing just one residue more than the biologically active C-terminal pentapeptide of C-peptide. We conclude that the degradation of C-peptide in kidney and placenta follows similar patterns, dominated by endopeptidase cleavages N-terminal of Leu.


Asunto(s)
Péptido C/metabolismo , Riñón/metabolismo , Placenta/metabolismo , Proinsulina/química , Secuencia de Aminoácidos , Animales , Sitios de Unión , Péptido C/química , Cromatografía Líquida de Alta Presión , Endopeptidasas/química , Humanos , Leucina/química , Espectrometría de Masas , Ratones , Datos de Secuencia Molecular , Péptidos/química , Estructura Terciaria de Proteína , Espectrometría de Masa por Ionización de Electrospray , Factores de Tiempo
13.
Neuroscience ; 122(4): 1013-23, 2003.
Artículo en Inglés | MEDLINE | ID: mdl-14643768

RESUMEN

Dynorphin A (1-17), an endogenous opioid neuropeptide, can have pathophysiological consequences at high concentrations through actions involving glutamate receptors. Despite evidence of excitotoxicity, the basic mechanisms underlying dynorphin-induced cell death have not been explored. To address this question, we examined the role of caspase-dependent apoptotic events in mediating dynorphin A (1-17) toxicity in embryonic mouse striatal neuron cultures. In addition, the role of opioid and/or glutamate receptors were assessed pharmacologically using dizocilpine maleate (MK(+)801), a non-equilibrium N-methyl-D-aspartate (NMDA) antagonist; 6-cyano-7-nitroquinoxaline-2,3-dione, a competitive alpha-amino-3-hydroxy-5-methylisoxazole-4-propionate (AMPA)/kainate antagonist; or (-)-naloxone, a general opioid antagonist. The results show that dynorphin A (1-17) (>or=10 nM) caused concentration-dependent increases in caspase-3 activity that were accompanied by mitochondrial release of cytochrome c and the subsequent death of cultured mouse striatal neurons. Moreover, dynorphin A-induced neurotoxicity and caspase-3 activation were significantly attenuated by the cell permeable caspase inhibitor, caspase-3 inhibitor-II (z-DEVD-FMK), further suggesting an apoptotic cascade involving caspase-3. AMPA/kainate receptor blockade significantly attenuated dynorphin A-induced cytochrome c release and/or caspase-3 activity, while NMDA or opioid receptor blockade typically failed to prevent the apoptotic response. Last, dynorphin-induced caspase-3 activation was mimicked by the ampakine CX546 [1-(1,4-benzodioxan-6-ylcarbonyl)piperidine], which suggests that the activation of AMPA receptor subunits may be sufficient to mediate toxicity in striatal neurons. These findings provide novel evidence that dynorphin-induced striatal neurotoxicity is mediated by a caspase-dependent apoptotic mechanism that largely involves AMPA/kainate receptors.


Asunto(s)
Apoptosis/efectos de los fármacos , Caspasas/metabolismo , Cuerpo Estriado/citología , Citocromos c/metabolismo , Dinorfinas/farmacología , Antagonistas de Aminoácidos Excitadores/farmacología , Neuronas/citología , Neuronas/efectos de los fármacos , Animales , Apoptosis/fisiología , Caspasa 3 , Células Cultivadas , Cuerpo Estriado/efectos de los fármacos , Cuerpo Estriado/metabolismo , Relación Dosis-Respuesta a Droga , Activación Enzimática/efectos de los fármacos , Activación Enzimática/fisiología , Femenino , Ratones , Ratones Endogámicos ICR , Neuronas/enzimología , Neuronas/metabolismo , Embarazo , Receptores AMPA/antagonistas & inhibidores , Receptores AMPA/metabolismo , Receptores de Ácido Kaínico/antagonistas & inhibidores , Receptores de Ácido Kaínico/metabolismo
14.
Cell Mol Life Sci ; 60(5): 1019-25, 2003 May.
Artículo en Inglés | MEDLINE | ID: mdl-12827290

RESUMEN

Processing of human proinsulin C-peptide and its C-terminal pentapeptide in blood serum was studied using reverse-phase HPLC and electrospray mass spectrometry. The results reveal degradation of both peptides, with a longer half-life for intact C-peptide than for the C-terminal pentapeptide. Products from C-peptide degradation were not distinguishable from the peptide background, suggesting endopeptidase degradation of C-peptide. In contrast, a set of products from the C-terminal pentapeptide were identifiable and corresponded to successive losses from the N terminus, showing that the pentapeptide is degraded by aminopeptidase in serum. Consistent with this finding, a slower degradation was found for the N-acetyl-protected pentapeptide. Removal of serum proteins by acetone precipitation produced N-terminally carbamate-modified C-peptide via a Schiff base intermediate (a ketimine with acetone), to which CO(2) was added and acetone removed, generating a cyclic side chain via anhydride formation. The modification was not seen with the pyroglutamate form of C-peptide, with the N-terminally acetylated C-peptide, or with a control peptide having N-terminal Phe, but was found with human C-peptide, its N-terminal tetrapeptide, and a rat C-peptide fragment (all with N-terminal Glu). Hence, the modification appears to require N-terminal Glu, but this is not the only prerequisite since the C-terminal pentapeptide and another control peptide (also starting with Glu) were not modified. A peptide aldimine Schiff base leading to CO(2) incorporation was detected with formaldehyde in NaHCO(3). The observation that C-peptide forms Schiff bases with ketones/aldehydes, enhancing covalent attachment of CO(2), may have biological implications.


Asunto(s)
Péptido C/metabolismo , Dióxido de Carbono/metabolismo , Fragmentos de Péptidos/metabolismo , Péptido C/sangre , Péptido C/química , Humanos , Bases de Schiff
15.
Growth Horm IGF Res ; 11(5): 303-13, 2001 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-11735249

RESUMEN

Peroxisome proliferator-activated receptor alpha (PPARalpha) plays a central role in glucose and lipid homeostasis. Mice lacking PPARalpha(-/-) have a sexually dimorphic phenotype. We have characterized the IGF system in wild type and PPARalpha-/- mice. In normal mice fasting IGF-I and the IGFBP-3 ternary complex were 2-fold higher in males than in females. PPARalpha influenced the IGF/IGFBP response to feeding, particularly in males. Compared to wild type, male PPARalpha-/- mice had 40% lower total fasting IGF-I concentrations, decreased ALS and less IGFBP-3 ternary complex formation, but within 4 h of refeeding there was an increase in IGF-I and IGFBP-3 ternary complex to values similar to controls. Circulating IGFBP protease activity was induced in male PPARalpha-/- mice during refeeding. IGFBP-1 and insulin concentrations were higher in males than females, and were increased by PPARalpha knockout, suggesting significant hepatic insulin resistance. We speculate that gender differences in the IGF system contribute to the PPARalpha-/- phenotype.


Asunto(s)
Ingestión de Alimentos/fisiología , Ayuno/fisiología , Proteína 3 de Unión a Factor de Crecimiento Similar a la Insulina/genética , Factor I del Crecimiento Similar a la Insulina/genética , Receptores Citoplasmáticos y Nucleares/fisiología , Factores de Transcripción/fisiología , Animales , Femenino , Insulina/sangre , Proteína 1 de Unión a Factor de Crecimiento Similar a la Insulina/sangre , Proteína 1 de Unión a Factor de Crecimiento Similar a la Insulina/genética , Proteína 1 de Unión a Factor de Crecimiento Similar a la Insulina/aislamiento & purificación , Proteína 3 de Unión a Factor de Crecimiento Similar a la Insulina/sangre , Proteína 3 de Unión a Factor de Crecimiento Similar a la Insulina/aislamiento & purificación , Masculino , Ratones , Ratones Noqueados , Estado Nutricional , Receptores Citoplasmáticos y Nucleares/deficiencia , Receptores Citoplasmáticos y Nucleares/genética , Caracteres Sexuales , Factores de Transcripción/deficiencia , Factores de Transcripción/genética
16.
Cell Mol Life Sci ; 58(9): 1323-6, 2001 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-11577987

RESUMEN

A recent finding of a novel class of retinol-active alcohol dehydrogenase (ADH) in frog prompted analysis of this activity in other vertebrate forms. Surprisingly, yet another and still more unrelated ADH was identified in chicken tissues. It was found to be a member of the aldo-keto reductase (AKR) enzyme family, not previously known as an ADH in vertebrates. Its terminal blocking group and the N-terminal segment, not assigned by protein and cDNA structure analysis, were determined by electrospray tandem mass spectrometry after protein isolation by two-dimensional gel electrophoresis. The N terminus is Acetyl-Ala- and the N-terminal segment contains two consecutive Asn residues. The results establish the new ADH enzyme of the AKR family and show the usefulness of combined gel separation and mass spectrometry in enzyme-characterization.


Asunto(s)
Alcohol Deshidrogenasa/química , Oxidorreductasas de Alcohol/química , Proteoma , Acetilación , Alcohol Deshidrogenasa/genética , Oxidorreductasas de Alcohol/genética , Aldehído Reductasa , Aldo-Ceto Reductasas , Secuencia de Aminoácidos , Animales , Pollos , Fragmentos de Péptidos/química , Ranidae , Espectrometría de Masa por Ionización de Electrospray , Vertebrados
17.
Cell Mol Life Sci ; 58(2): 307-11, 2001 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-11289312

RESUMEN

Protein patterns in cells collected from benign prostatic tissues and prostate carcinomas were analyzed using two-dimensional polyacrylamide gel electrophoresis and mass spectrometry. Polypeptide expression was evaluated by computer-assisted image analysis (PDQUEST). Proteins expressed by prostate tumors were identified via in-gel digestion and subsequent matrix-assisted laser desorption/ionization mass spectrometry. In addition to cytoskeletal and mitochondrial proteins, a 40-kDa protein was identified as prostatic acid phosphatase (PAP). PAP expression decreased approximately twofold between benign and malignant tissue. Increased expression of heat shock protein 70 and decreased expression of tropomyosin 1 were also observed in the malignant tissue. The analysis of prostate material by two-dimensional gel electrophoresis and mass spectrometry shows that particular proteins are of interest as markers of disease.


Asunto(s)
Proteínas de Drosophila , Electroforesis en Gel Bidimensional/métodos , Proteínas de Neoplasias/análisis , Neoplasias de la Próstata/química , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción/métodos , Fosfatasa Ácida/análisis , Adenocarcinoma/química , Anciano , Anciano de 80 o más Años , Proteínas HSP70 de Choque Térmico/análisis , Humanos , Masculino , Persona de Mediana Edad , Hiperplasia Prostática/metabolismo , Tropomiosina/análisis
18.
J Am Soc Mass Spectrom ; 12(3): 337-42, 2001 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-11281609

RESUMEN

Tryptic digestion of the 150-residue human acidic salivary proline-rich protein 1 (PRP-1) generated eight peptides, two of which corresponded to the N-terminal 30-residue segment. In each of the other six tryptic peptides, a consensus repeat with the structure PQGPPQQGG was present. A facile Gln-Gly cleavage between the second and the third residues of the repeat was observed during collision-induced dissociation experiments. We postulate possible mechanisms to account for this reactivity, involving attack on the peptidyl carbonyl group by the Gln sidechain. Significantly, the Gln-Gly cleavage has been shown to be biologically important in the bacterial degradation of PRPs in saliva, generating bacteria-binding Pro-Gln C-termini. We suggest a link between the gas-phase chemistry and the biochemical degradation of these molecules.


Asunto(s)
Dipéptidos/química , Péptidos/química , Proteínas y Péptidos Salivales/química , Secuencia de Aminoácidos , Glutamina/química , Glicina/química , Humanos , Hidrólisis , Espectrometría de Masas , Datos de Secuencia Molecular , Fragmentos de Péptidos/química , Fragmentos de Péptidos/aislamiento & purificación , Péptidos/aislamiento & purificación , Dominios Proteicos Ricos en Prolina , Tripsina
19.
Rapid Commun Mass Spectrom ; 15(9): 713-20, 2001.
Artículo en Inglés | MEDLINE | ID: mdl-11319794

RESUMEN

An understanding of the gas-phase dissociation of protonated peptides within the mass spectrometer is essential for automated high-throughput protein identification. In this communication we describe a facile cleavage of the Gln-Gly peptide bond under low-collisional energy conditions. A variety of synthetic peptides have been analysed where key amino acids have been substituted within the sequence PQGPPQQGGR, which is a consensus repeat present in the tryptic peptides of acidic proline-rich protein 1 (PRP-1). The collision-induced dissociation spectra obtained from the PRP-1 tryptic peptides and the synthetic peptides indicate that facile Gln-Gly cleavage occurs when an X-Gln-Gly-Y sequence is present in a peptide, where X is any amino acid and Y any amino acid other than Gly.


Asunto(s)
Dipéptidos/química , Péptidos/química , Secuencia de Aminoácidos , Sustitución de Aminoácidos , Hidrólisis , Datos de Secuencia Molecular , Tripsina
20.
FEBS Lett ; 492(1-2): 119-22, 2001 Mar 09.
Artículo en Inglés | MEDLINE | ID: mdl-11248248

RESUMEN

We have isolated a posttranslationally modified form of peptide YY (PYY) from porcine intestine and shown by MALDI-TOF and electrospray tandem mass spectrometry that it is phosphorylated at Ser(13). Phospho-PYY exhibits high affinity for binding to neuropeptide Y (NPY) receptors Y1, Y2 and Y5. The IC(50) values with the Y1, Y2, and Y5 receptor subtypes were for NPY 2.4, 3.1, and 3.3 nM, for PYY 2.3, 0.94, and 3.2 nM, and for phospho-PYY 4.6, 2.2, and 5.5 nM, respectively. Phospho-PYY potently inhibits forskolin-stimulated cAMP accumulation in SK-N-MC cells with an IC(50) value of 0.5 nM compared to 0.15 nM for non-phosphorylated PYY. The finding of phosphorylation of PYY is unusual among hormonal peptides, and emphasizes the importance of direct protein analysis of gene products.


Asunto(s)
Mucosa Intestinal/metabolismo , Péptido YY/metabolismo , Serina/metabolismo , Secuencia de Aminoácidos , Animales , AMP Cíclico/metabolismo , Humanos , Péptido YY/química , Fosforilación , Análisis de Secuencia de Proteína , Homología de Secuencia de Aminoácido , Porcinos , Células Tumorales Cultivadas
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