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1.
Health Expect ; 27(3): e14053, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38698629

RESUMEN

INTRODUCTION: This exploratory literature review seeks to examine the literature around commissioning processes in the co-production of health and care services, focusing on two questions: How do health and care commissioning processes facilitate and/or pose barriers to co-production in service design and delivery? What are the contextual factors that influence these processes? METHOD: A systematic search of three databases (Medline, Public Health and Social Policy and Practice) and a search platform (Web of Science) was conducted for the period 2008-2023. A total of 2675 records were retrieved. After deduplication, 1925 were screened at title and abstract level. Forty-seven reports from 42 United Kingdom and Ireland studies were included in the review. A thematic synthesis of included studies was conducted in relation to the research questions. RESULTS: The review identified one overarching theme across the synthesised literature: the complexity of the commissioning landscape. Three interconnected subthemes illuminate the contextual factors that influence this landscape: commissioners as leaders of co-production; navigating relationships and the collective voice. CONCLUSION: Commissioning processes were commonly a barrier to the co-production of health and care services. Though co-production was an aspiration for many commissioners, the political and economic environment and service pressures meant that it was often not fully realised. More flexible funding models, longer-term pilot projects, an increased emphasis in social value across the health and care system and building capacity for strong leadership in commissioning is needed. PATIENT AND PUBLIC CONTRIBUTION: Patients and the public did not contribute to this review as it was a small piece of work following on from a completed project, with no budget for public involvement.


Asunto(s)
Atención a la Salud , Reino Unido , Irlanda , Humanos , Atención a la Salud/organización & administración , Medicina Estatal/organización & administración , Política de Salud
2.
Front Psychol ; 7: 868, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27375544

RESUMEN

The general and sport psychology research converge to point to a complex relationship between depressive experiences and human performance. The purpose of this study was to explore the depressive experiences of top level athletes and the relationship of such experiences with sport performance. Twelve autobiographies of elite athletes representing eight sports were analyzed. The autobiographical analysis was informed by narrative tradition, using three types of narrative analysis: categorical content, categorical form, and holistic content. The analysis revealed a temporal aspect to the depressive experiences that the athletes reported. Initially, sport represented a form of escape from the depressive symptoms which had been exacerbated by both external stressors (e.g., experiencing bereavement) and internal stressors (e.g., low self-esteem). However, in time, the athletes typically reached a stage when the demands of their sport shifted from being facilitative to being debilitative in nature with an intensification of their depressive symptoms. This was accompanied by deliberations about continuing their engagement in sport and an acceptance that they could no longer escape from their symptoms, with or without sport. The findings extend the extant literature by suggesting a reciprocal relationship between depressive experiences and sport performance, and they support the general psychology literature relating to the negative impact of depression on performance. The applied implications of these findings are discussed emphasizing the importance of early identification of depressive symptoms and the adoption of a proactive approach in the prevention and management of symptoms.

3.
Infect Immun ; 62(11): 5010-9, 1994 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-7927782

RESUMEN

Filamentous hemagglutinin (FHA) is a major adhesin present on the surface of the gram-negative respiratory pathogen Bordetella pertussis. A number of binding mechanisms have been described for the interaction of FHA with eukaryotic cells. We have focused on its function as a sulfated polysaccharide-binding protein and on identifying potential receptors for FHA on the epithelial cell surface. Using a thin-layer overlay technique, we found that FHA binds specifically to sulfated glycolipids but not to gangliosides or other neutral glycolipids. These results suggest that epithelial cell surface sulfated glycolipids function as receptors for FHA. Further studies demonstrated that a Chinese hamster ovary (CHO) cell strain deficient in glycosaminoglycan expression exhibits greatly diminished attachment to FHA. By FHA-Affi-Gel chromatography, a putative receptor for FHA that has characteristics consistent with a heparan sulfate proteoglycan was isolated from epithelial cell extracts. In addition, by using recombinant FHA fusion proteins, a specific glycosaminoglycan-binding domain located near the N terminus of the FHA molecule was identified. Our results indicate that the B. pertussis adhesin FHA may utilize sulfated glycolipids and proteoglycans commonly found on the surface of human cells and tissues to initiate infection.


Asunto(s)
Adhesinas Bacterianas/metabolismo , Bordetella pertussis/patogenicidad , Hemaglutininas/metabolismo , Heparitina Sulfato/metabolismo , Factores de Virulencia de Bordetella , Adhesinas Bacterianas/química , Animales , Secuencia de Bases , Sitios de Unión , Bordetella , Células CHO , Cricetinae , Cartilla de ADN/química , Genes Bacterianos , Glucolípidos/metabolismo , Células HeLa , Humanos , Técnicas In Vitro , Microscopía Electrónica , Datos de Secuencia Molecular , Peso Molecular , Mapeo Restrictivo , Sulfoglicoesfingolípidos/metabolismo
4.
J Mol Biol ; 241(1): 110-24, 1994 Aug 05.
Artículo en Inglés | MEDLINE | ID: mdl-7519681

RESUMEN

The filamentous hemagglutinin (FHA) of Bordetella pertussis is an adhesin that binds the bacteria to cells of the respiratory epithelium in whooping-cough infections. Mature FHA is a 220 kDa secretory protein that is highly immunogenic and has been included in acellular vaccines. We have investigated its structure by combining electron microscopy and circular dichroism spectroscopy (CD) with computational analysis of its amino acid sequence. The FHA molecule is 50 nm in length and has the shape of a horseshoe nail: it has a globular head that appears to consist of two domains; a 35 nm-long shaft that averages 4 nm in width, but tapers slightly from the head end; and a small, flexible, tail. Mass measurements by scanning transmission electron microscopy establish that FHA is a monomer. Its sequence contains two regions of tandem 19-residue pseudo-repeats: the first, of 38 cycles, starts at residue 344; the second, of 13 cycles, starts at residue 1440. The repeat motifs are predicted to consist of short beta-strands separated by beta-turns, and secondary structure measurements by CD support this prediction. We propose a hairpin model for FHA in which the head is composed of the terminal domains; the shaft consists mainly of the repeat regions conformed as amphipathic, hyper-elongated beta-sheets, with their hydrophobic faces apposed; and the tail is composed of the intervening sequence. Further support for the model was obtained by immuno-labeling electron microscopy. The 19-residue repeats of FHA have features in common with the leucine-rich repeats (LRRs) that are present in many eukaryotic proteins, including some adhesion factors. The model is also compared with the two other classes of filamentous proteins that are rich in beta-structure, i.e. viral adhesins and two beta-helical secretory proteins. Our proposed structure implies how the functionally important adhesion sites and epitopes of FHA are distributed: its tripeptide (RGD) integrin-binding site is assigned to the tail; the putative hemagglutination site forms part of the head; and two classes of immunodominant epitopes are assigned to opposite ends of the molecule. Possible mechanisms are discussed for two modes of FHA-mediated adhesion.


Asunto(s)
Adhesinas Bacterianas , Proteínas Bacterianas/química , Bordetella pertussis/química , Hemaglutininas/química , Estructura Secundaria de Proteína , Factores de Virulencia de Bordetella , Secuencia de Aminoácidos , Aminoácidos/análisis , Antígenos Bacterianos/química , Proteínas Bacterianas/ultraestructura , Bordetella pertussis/ultraestructura , Quimotripsina , Secuencia de Consenso , Epítopos/análisis , Hemaglutininas/ultraestructura , Procesamiento de Imagen Asistido por Computador , Microscopía Electrónica , Microscopía Electrónica de Transmisión de Rastreo , Modelos Biológicos , Datos de Secuencia Molecular , Peso Molecular , Conformación Proteica , Secuencias Repetitivas de Ácidos Nucleicos , Homología de Secuencia de Aminoácido
5.
Infect Immun ; 62(3): 769-78, 1994 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-8112848

RESUMEN

Bordetella pertussis, the etiologic agent of whooping cough, produces an outer membrane-associated filamentous hemagglutinin (FHA) which is the major adhesin of this organism. FHA exhibits a lectin-like activity for heparin and dextran sulfate. By using in vitro adherence assays to cultured epithelial cells, the attachment of B. pertussis was reduced in the presence of sulfated polysaccharides such as heparin and dextran sulfate but not in the presence of dextran, indicating the crucial role of polysaccharide sulfation. In addition, inhibition of cellular sulfation by chlorate treatment of the cells resulted in a reduction of B. pertussis adherence, suggesting that epithelial cell surface-exposed sulfated glycoconjugates may serve as receptors for the microorganism. B. pertussis mutant strains deficient in FHA production expressed residual adherence that was no longer inhibited by sulfated polysaccharides. In addition, purified FHA displayed heparin-inhibitable binding to epithelial cells. Mapping experiments of the heparin-binding site of FHA indicated that this site is different from the RGD site and the recently proposed carbohydrate-binding site involved in the interaction of FHA with lactosylceramide. This result demonstrates that FHA contains at least three different binding sites, a feature unusual for bacterial adhesions but similar to features of eukaryotic adhesins and extracellular matrix proteins.


Asunto(s)
Adhesinas Bacterianas , Adhesión Bacteriana , Bordetella pertussis/fisiología , Hemaglutininas/metabolismo , Heparina/farmacología , Lectinas/metabolismo , Factores de Virulencia de Bordetella , Animales , Sitios de Unión , Células CHO , Carbohidratos/farmacología , Cloratos/farmacología , Cricetinae , Sulfato de Dextran/metabolismo , Sulfato de Dextran/farmacología , Células HeLa , Hemaglutinación/efectos de los fármacos , Heparina/metabolismo , Humanos , Oligopéptidos/metabolismo
6.
Mol Microbiol ; 9(3): 469-76, 1993 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-8412696

RESUMEN

We have examined the surface topography and channel connectivity of a naturally crystalline porin that is known to be functional, and whose structure has not been perturbed by detergent extraction. A three-dimensional density map, calculated from two independent tilt series of negatively stained cell envelopes, reveals three separate channels per trimer on one side (the 'smooth' side), and a single common opening at the other ('rough') side. This arrangement is consistent with the molecular structures recently determined at high resolution by X-ray crystallography for three other porins after detergent solubilization, and implies that the Bordetella pertussis porin may have the same kind of folding. Surface relief maps calculated from electron micrographs of cell envelopes contrasted by unidirectional shadowing clearly show that the side with single opening (i.e. the rough side) represents the external surface.


Asunto(s)
Bordetella pertussis/ultraestructura , Membrana Celular/ultraestructura , Porinas/ultraestructura , Cristalografía por Rayos X , Procesamiento de Imagen Asistido por Computador , Microscopía Electrónica , Conformación Proteica , Fracciones Subcelulares/ultraestructura
7.
J Biol Chem ; 266(28): 18827-31, 1991 Oct 05.
Artículo en Inglés | MEDLINE | ID: mdl-1918002

RESUMEN

The adherence of the human respiratory pathogen, Bordetella pertussis, to purified glycosphingolipids was investigated using thin layer chromatography overlay assays. Both virulent and avirulent strains of B. pertussis bound to asialo GM1. The bacterium did not bind to the gangliosides GM1, GD1a, GD1b, and GT1b, nor to lactosylceramide, trihexosylceramide, globoside, or Forssman antigen. However, after treatment of the chromatography plates with sialidase, B. pertussis bound to the gangliosides GM1, GM2, GD1a, GD1b, and GT1b but not to GM3. Comparison of the oligosaccharide structures of these gangliosides suggests that the minimum sugar structure needed for avid bacterial binding is GalNAc beta 4Gal. This structure has been previously implicated as a receptor for other human respiratory pathogens (Krivan, H. C., Roberts, D. D., Ginsburg, V. (1988) Proc. Natl. Acad. Sci. U.S.A 85, 6157-6161). Virulent strains of B. pertussis also bound specifically to sulfatide. This response was dose-dependent and inhibited by the anionic polysaccharide dextran sulfate. The sulfated-sugars dextran sulfate, fucoidan, and heparin inhibited the attachment of virulent strains of B. pertussis to human WiDr cells and to hamster trachea cells indicating that sulfatides on the surface of mammalian cells may function as a receptor for B. pertussis. The occurrence of both sulfatides and asialo GM1 in human lung and trachea suggests that these glycolipids may serve as specific receptors for B. pertussis.


Asunto(s)
Adhesión Bacteriana , Bordetella pertussis/metabolismo , Gangliósido G(M1) , Glicoesfingolípidos/metabolismo , Sulfoglicoesfingolípidos/metabolismo , Animales , Bordetella pertussis/patogenicidad , Secuencia de Carbohidratos , Células Cultivadas , Cromatografía en Capa Delgada , Cricetinae , Glicoesfingolípidos/química , Humanos , Datos de Secuencia Molecular , Células Tumorales Cultivadas , Virulencia
8.
Mol Microbiol ; 5(7): 1649-56, 1991 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-1658537

RESUMEN

Bordetella pertussis produces a porin protein which is a prominent outer membrane component found in both virulent and avirulent strains. N-terminal amino acid analysis of purified B. pertussis porin was performed and this amino acid sequence was used to design an oligonucleotide that was then utilized to screen a lambda gt11 library containing randomly sheared fragments of DNA from B. pertussis strain 347. One clone, lambda BpPor, was identified and subcloned into pUC18. A portion of the DNA insert in this subclone, pBpPor1, was sequenced and shown to contain the N-terminal region of the structural porin gene. This truncated gene sequence was used to design an additional oligonucleotide that was used to identify a clone, pBpPor2, which overlapped with pBpPor1 and contained a termination codon. The structural gene deduced from this sequence would encode a 365-amino-acid polypeptide with a predicted mass of 39,103 daltons. The predicted product also contains a signal sequence of 20 residues that is similar to that found in other porin genes. The predicted B. pertussis porin protein sequence contains regions that are homologous to regions found in porins expressed by Neisseria species and Escherichia coli, including the presence of phenylalanine as the carboxy-terminal amino acid. DNA hybridization studies indicated that both virulent and avirulent strains of B. pertussis contain only one copy of this gene and that Bordetella bronchiseptica and Bordetella parapertussis contain a similar gene.


Asunto(s)
Proteínas de la Membrana Bacteriana Externa/genética , Bordetella pertussis/genética , Secuencia de Aminoácidos , Proteínas de la Membrana Bacteriana Externa/química , Secuencia de Bases , Bordetella/clasificación , Bordetella/genética , Clonación Molecular , Escherichia coli/genética , Biblioteca de Genes , Genes Bacterianos , Datos de Secuencia Molecular , Neisseria gonorrhoeae/genética , Sistemas de Lectura Abierta/genética , Porinas , Alineación de Secuencia , Homología de Secuencia de Ácido Nucleico
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