Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 36
Filtrar
2.
Microbiome ; 11(1): 226, 2023 10 16.
Artículo en Inglés | MEDLINE | ID: mdl-37845716

RESUMEN

BACKGROUND: Mammalian mucosal barriers secrete antimicrobial peptides (AMPs) as critical, host-derived regulators of the microbiota. However, mechanisms that support microbiota homeostasis in response to inflammatory stimuli, such as supraphysiologic oxygen, remain unclear. RESULTS: We show that supraphysiologic oxygen exposure to neonatal mice, or direct exposure of intestinal organoids to supraphysiologic oxygen, suppresses the intestinal expression of AMPs and alters intestinal microbiota composition. Oral supplementation of the prototypical AMP lysozyme to hyperoxia-exposed neonatal mice reduced hyperoxia-induced alterations in their microbiota and was associated with decreased lung injury. CONCLUSIONS: Our results identify a gut-lung axis driven by intestinal AMP expression and mediated by the intestinal microbiota that is linked to lung injury in newborns. Together, these data support that intestinal AMPs modulate lung injury and repair. Video Abstract.


Asunto(s)
Microbioma Gastrointestinal , Hiperoxia , Lesión Pulmonar , Animales , Ratones , Microbioma Gastrointestinal/fisiología , Lesión Pulmonar/complicaciones , Péptidos Antimicrobianos , Hiperoxia/complicaciones , Pulmón , Oxígeno , Mamíferos
3.
Neurotherapeutics ; 20(6): 1723-1745, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37723406

RESUMEN

We sought to prospectively characterize the nutritional status of adults ≥ 19 years (n = 22, 27% males) and children (n = 38, 61% male) with genetically-confirmed primary mitochondrial disease (PMD) to guide development of precision nutritional support strategies to be tested in future clinical trials. We excluded subjects who were exclusively tube-fed. Daily caloric requirements were estimated using World Health Organization (WHO) equations to predict resting energy expenditure (REE) multiplied by an activity factor (AF) based on individual activity levels. We developed a Mitochondrial Disease Activity Factors (MOTIVATOR) score to encompass the impact of muscle fatigue typical of PMD on physical activity levels. PMD cohort daily diet intake was estimated to be 1,143 ± 104.1 kcal in adults (mean ± SEM, 76.2% of WHO-MOTIVATOR predicted requirement), and 1,114 ± 62.3 kcal in children (86.4% predicted). A total of 11/22 (50%) adults and 18/38 (47.4%) children with PMD consumed ≤ 75% predicted daily Kcal needs. Malnutrition was identified in 16/60 (26.7%) PMD subjects. Increased protein and fat intake correlated with improved muscle strength in those with insufficient daily Kcal intake (≤ 75% predicted); higher protein and fat intake correlated with decreased muscle fatigue; and higher protein, fat, and carbohydrate intake correlated with improved quality of life (QoL). These data demonstrate the frequent occurrence of malnutrition in PMD and emphasize the critical need to devise nutritional interventions to optimize clinical outcomes.


Asunto(s)
Desnutrición , Enfermedades Mitocondriales , Adulto , Niño , Humanos , Masculino , Femenino , Estado Nutricional , Calidad de Vida , Ingestión de Energía , Fatiga Muscular , Metabolismo Energético
4.
medRxiv ; 2023 Nov 10.
Artículo en Inglés | MEDLINE | ID: mdl-37398134

RESUMEN

RATIONALE: Bronchopulmonary dysplasia (BPD) is the most common morbidity affecting very preterm infants. Gut fungal and bacterial microbial communities contribute to multiple lung diseases and may influence BPD pathogenesis. METHODS: We performed a prospective, observational cohort study comparing the multikingdom fecal microbiota of 144 preterm infants with or without moderate to severe BPD by sequencing the bacterial 16S and fungal ITS2 ribosomal RNA gene. To address the potential causative relationship between gut dysbiosis and BPD, we used fecal microbiota transplant in an antibiotic-pseudohumanized mouse model. Comparisons were made using RNA sequencing, confocal microscopy, lung morphometry, and oscillometry. RESULTS: We analyzed 102 fecal microbiome samples collected during the second week of life. Infants who later developed BPD showed an obvious fungal dysbiosis as compared to infants without BPD (NoBPD, p = 0.0398, permutational multivariate ANOVA). Instead of fungal communities dominated by Candida and Saccharomyces, the microbiota of infants who developed BPD were characterized by a greater diversity of rarer fungi in less interconnected community architectures. On successful colonization, the gut microbiota from infants with BPD augmented lung injury in the offspring of recipient animals. We identified alterations in the murine intestinal microbiome and transcriptome associated with augmented lung injury. CONCLUSIONS: The gut fungal microbiome of infants who will develop BPD is dysbiotic and may contribute to disease pathogenesis.

5.
Front Nutr ; 10: 1168582, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37384109

RESUMEN

Introduction: Dysbiosis of the gut microbiome may augment lung disease via the gut-lung axis. Proteobacteria may contribute to tissue proteolysis followed by neutrophil recruitment, lung tissue injury, and perpetuation of chronic inflammation. To study the effects of probiotics across the gut-lung axis, we sought to determine if a Lactobacillus probiotic and herbal blend was safe and well-tolerated in healthy volunteers and asthmatic patients. Methods: We conducted a 1-month randomized, open-label clinical trial in Cork, Ireland with healthy and asthmatic patients who took the blend twice a day. The primary endpoint was safety with exploratory endpoints including quality of life, lung function, gut microbiome ecology, and inflammatory biomarkers. Results: All subjects tolerated the blend without adverse events. Asthmatic subjects who took the blend showed significant improvements in lung function as measured by forced expiratory volume and serum short chain fatty acid levels from baseline to Week 4. The gut microbiome of asthmatic subjects differed significantly from controls, with the most prominent difference in the relative abundance of the proteobacteria Escherichia coli. Administration of the probiotic maintained overall microbial community architecture with the only significant difference being an increase in absolute abundance of the probiotic strains measured by strain-specific PCR. Conclusion: This study supports the safety and efficacy potential of a Lactobacillus probiotic plus herbal blend to act on the gut-lung axis. However, due to the lack of a control group, a longer blinded, placebo-controlled study will be warranted to confirm the efficacy improvements observed in this trial. Clinical trial registration: https://clinicaltrials.gov/, identifier NCT05173168.

6.
Int J Mol Sci ; 24(10)2023 May 13.
Artículo en Inglés | MEDLINE | ID: mdl-37240055

RESUMEN

In cystic fibrosis (CF), pulmonary infection with Pseudomonas aeruginosa is a cause of increased morbidity and mortality, especially in patients for whom infection becomes chronic and there is reliance on long-term suppressive therapies. Current antimicrobials, though varied mechanistically and by mode of delivery, are inadequate not only due to their failure to eradicate infection but also because they do not halt the progression of lung function decline over time. One of the reasons for this failure is thought to be the biofilm mode of growth of P. aeruginosa, wherein self-secreted exopolysaccharides (EPSs) provide physical protection against antibiotics and an array of niches with resulting metabolic and phenotypic heterogeneity. The three biofilm-associated EPSs secreted by P. aeruginosa (alginate, Psl, and Pel) are each under investigation and are being exploited in ways that potentiate antibiotics. In this review, we describe the development and structure of P. aeruginosa biofilms before examining each EPS as a potential therapeutic target for combating pulmonary infection with P. aeruginosa in CF, with a particular focus on the current evidence for these emerging therapies and barriers to bringing these therapies into clinic.


Asunto(s)
Fibrosis Quística , Infecciones por Pseudomonas , Humanos , Antibacterianos/farmacología , Antibacterianos/uso terapéutico , Antibacterianos/metabolismo , Pseudomonas aeruginosa/metabolismo , Fibrosis Quística/tratamiento farmacológico , Alginatos/metabolismo , Biopelículas , Adyuvantes Inmunológicos/uso terapéutico , Adyuvantes Farmacéuticos/uso terapéutico , Pulmón , Infecciones por Pseudomonas/tratamiento farmacológico
7.
Expert Rev Respir Med ; 17(4): 295-304, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-37043239

RESUMEN

INTRODUCTION: Pulmonary exacerbations are common events in children with cystic fibrosis (CF) and are usually treated with oral antibiotics on an outpatient basis. Even these mild clinical events are clinically meaningful and contribute to the progression of lung disease. AREAS COVERED: This review discusses the challenges in diagnosing pulmonary exacerbations in children in the absence of a standardized definition. It describes an approach to the management of these events and emphasizes knowledge gaps and areas of future research directions. Information to write this narrative review was collected from 1) a PubMed search [keywords: exacerbation, children, cystic fibrosis] that was not limited by date 2) a hand search of references of retrieved literature 3) personal expertise of the literature and the management of cystic fibrosis. EXPERT OPINION: Pulmonary exacerbations require prompt diagnosis and management to preserve lung function. More work is needed to understand the impact of CFTR modulators on the frequency and severity of these events and how they influence approaches to management. In a new era of CF care, there is a need to incorporate sensitive outcome measures into clinical care to inform treatment decisions and track treatment response.


Asunto(s)
Fibrosis Quística , Niño , Humanos , Fibrosis Quística/diagnóstico , Fibrosis Quística/tratamiento farmacológico , Pacientes Ambulatorios , Antibacterianos/uso terapéutico , Pulmón
8.
Antibiotics (Basel) ; 12(3)2023 Mar 16.
Artículo en Inglés | MEDLINE | ID: mdl-36978460

RESUMEN

Bacteriophages (phages) are antimicrobials with resurgent interest that are being investigated for the treatment of antibiotic refractory infection, including for Pseudomonas aeruginosa (Pa) lung infection in cystic fibrosis (CF). In vitro work supports the use of this therapy in planktonic and biofilm culture models; however, consistent data are lacking for efficacy across different clinical Pa strains, culture models, and in combination with antibiotics in clinical use. We first examined the efficacy of a 4-phage cocktail as an adjunct to our CF centre's first-line systemic combination antibiotic therapy (ceftazidime + tobramycin) for 16 different clinical Pa strains and then determined subinhibitory interactions for a subset of these strains with each antibiotic in planktonic and biofilm culture. When a 4-phage cocktail (4 × 108 PFU/mL) was added to a ceftazidime-tobramycin combination (ceftazidime 16 mg/mL + tobramycin 8 mg/mL), we observed a 1.7-fold and 1.3-fold reduction in biofilm biomass and cell viability, respectively. The four most antibiotic resistant strains in biofilm were very susceptible to phage treatment. When subinhibitory concentrations of antibiotics and phages were investigated, we observed additivity/synergy as well as antagonism/inhibition of effect that varied across the clinical strains and culture model. In general, more additivity was seen with the phage-ceftazidime combination than with phage-tobramycin, particularly in biofilm culture, where no instances of additivity were seen when phages were combined with tobramycin. The fact that different bacterial strains were susceptible to phage treatment when compared to standard antibiotics is promising and these results may be relevant to ongoing clinical trials exploring the use of phages, in particular in the selection of subjects for clinical trials.

9.
bioRxiv ; 2023 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-36993189

RESUMEN

Mammalian mucosal barriers secrete antimicrobial peptides (AMPs) as critical host-derived regulators of the microbiota. However, mechanisms that support homeostasis of the microbiota in response to inflammatory stimuli such as supraphysiologic oxygen remain unclear. Here, we show that neonatal mice breathing supraphysiologic oxygen or direct exposure of intestinal organoids to supraphysiologic oxygen suppress the intestinal expression of AMPs and alters the composition of the intestinal microbiota. Oral supplementation of the prototypical AMP lysozyme to hyperoxia exposed neonatal mice reduced hyperoxia-induced alterations in their microbiota and was associated with decreased lung injury. Our results identify a gut-lung axis driven by intestinal AMP expression and mediated by the intestinal microbiota that is linked to lung injury. Together, these data support that intestinal AMPs modulate lung injury and repair. In Brief: Using a combination of murine models and organoids, Abdelgawad and Nicola et al. find that suppression of antimicrobial peptide release by the neonatal intestine in response to supra-physiological oxygen influences the progression of lung injury likely via modulation of the ileal microbiota. Highlights: Supraphysiologic oxygen exposure alters intestinal antimicrobial peptides (AMPs).Intestinal AMP expression has an inverse relationship with the severity of lung injury.AMP-driven alterations in the intestinal microbiota form a gut-lung axis that modulates lung injury.AMPs may mediate a gut-lung axis that modulates lung injury.

10.
Pathogens ; 12(2)2023 Jan 17.
Artículo en Inglés | MEDLINE | ID: mdl-36839426

RESUMEN

Respiratory syncytial virus (RSV) is a leading cause of severe lower respiratory tract disease, especially in young children. Despite its global impact on healthcare, related to its high prevalence and its association with significant morbidity, the current therapy is still mostly supportive. Moreover, while more than 50 years have passed since the first trial of an RSV vaccine (which unfortunately caused enhanced RSV disease), no vaccine has been approved for RSV prevention. In the last two decades, our understanding of the pathogenesis and immunopathology of RSV have continued to evolve, leading to significant advancements in RSV prevention strategies. These include both the development of new potential vaccines and the successful implementation of passive immunization, which, together, will provide coverage from infancy to old age. In this review, we provide an update of the current treatment options for acute disease (RSV-specific and -non-specific) and different therapeutic approaches focusing on RSV prevention.

11.
Microorganisms ; 9(3)2021 Mar 22.
Artículo en Inglés | MEDLINE | ID: mdl-33810202

RESUMEN

Antibiotic treatment for Pseudomonas aeruginosa (Pa) in cystic fibrosis is limited in efficacy and may lead to multi-drug resistance (MDR). Alternatives such as bacteriophages are being explored but well designed, and controlled trials are crucial. The rational selection of patients with bacteriophage susceptible infections is required for both safety and efficacy monitoring. We questioned whether bacteriophage susceptibility profiles were constant or variable over time, variability having been reported with antibiotics. Serial Pa isolates (n = 102) from 24 chronically infected cystic fibrosis (CF) patients over one year were investigated with plaque and antibiotic disc diffusion assays. Variable number tandem repeat (VNTR) analysis identified those patients with >1 isolate. A median (range) of 4 (3-6) isolates/patient were studied. Twenty-one (87.5%) individuals had a single VNTR type; three (12.5%) had two VNTR types at different times. Seventy-five percent of isolates were sensitive to bacteriophage at ≥ 1 concentration; 50% of isolates were antibiotic multidrug resistant. Serial isolates, even when representing a single VNTR type, varied in sensitivity to both bacteriophages and antibiotics. The rates of sensitivity to bacteriophage supports the development of this therapy; however, the variability in response has implications for the selection of patients in future trials which must be on the basis of current, not past, isolate testing.

12.
Int J Mol Sci ; 22(4)2021 Feb 22.
Artículo en Inglés | MEDLINE | ID: mdl-33671516

RESUMEN

The treatment of lung infection in the context of cystic fibrosis (CF) is limited by a biofilm mode of growth of pathogenic organisms. When compared to planktonically grown bacteria, bacterial biofilms can survive extremely high levels of antimicrobials. Within the lung, bacterial biofilms are aggregates of microorganisms suspended in a matrix of self-secreted proteins within the sputum. These structures offer both physical protection from antibiotics as well as a heterogeneous population of metabolically and phenotypically distinct bacteria. The bacteria themselves and the components of the extracellular matrix, in addition to the signaling pathways that direct their behaviour, are all potential targets for therapeutic intervention discussed in this review. This review touches on the successes and failures of current anti-biofilm strategies, before looking at emerging therapies and the mechanisms by which it is hoped they will overcome current limitations.


Asunto(s)
Antibacterianos/farmacología , Biopelículas/efectos de los fármacos , Fibrosis Quística/microbiología , Enfermedades Pulmonares/microbiología , Alginatos/farmacología , Antibacterianos/administración & dosificación , Bacteriófagos , Comunicación Celular/efectos de los fármacos , GMP Cíclico/análogos & derivados , GMP Cíclico/metabolismo , Fibrosis Quística/complicaciones , Humanos , Hierro/metabolismo , Enfermedades Pulmonares/tratamiento farmacológico , Percepción de Quorum/efectos de los fármacos
13.
Paediatr Respir Rev ; 31: 9-11, 2019 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-30975518

RESUMEN

Novel drug development offers people with cystic fibrosis exciting opportunities but is not without challenges. Currently, there is an understandable emphasis on protecting patients' physical health when developing treatments. However, there appears to be little consideration of how novel drug development impacts on psychosocial wellbeing, or the downstream consequences of this. Using an illustrative case and reviewing the literature we explore themes regarding the psychosocial impact of trial participation and novel drug development and identify areas requiring further research. Through this, we hope to prepare healthcare professionals to better understand the needs of their patients in this rapidly evolving landscape.


Asunto(s)
Ensayos Clínicos como Asunto , Fibrosis Quística/tratamiento farmacológico , Desarrollo de Medicamentos , Participación del Paciente/psicología , Humanos
14.
Cytometry B Clin Cytom ; 96(5): 375-378, 2019 09.
Artículo en Inglés | MEDLINE | ID: mdl-29669178

RESUMEN

Primary effusion lymphoma (PEL) is a rare B cell lymphoproliferative disorder that arises predominantly in body cavities causing malignant effusions. The incidence of PEL is very low, accounting for approximately 4% of all HIV-associated non-Hodgkin lymphomas. PEL has also been described in elderly patients and after solid-organ transplantation. It is associated in all cases with human herpes virus 8 (HHV8). We describe a case of PEL in a 88-year-old HIV-negative woman who presented with progressive dyspnea and moderate right-sided pleural effusion without significant lymphadenopathies or other effusions. The cytological study of the pleural fluid revealed a dense proliferation of large plasmablastic cells. A six-color multiparametric flow cytometry immunophenotyping study was carried out, and revealed 45% of large in size and high cellular complexity cells positive for CD45 (dim), CD38, CD138, CD30 and HLA-DR; and negative for CD19, CD20, cytoplasmatic CD79a, surface and cytoplasmic light chains Kappa and Lambda, CD3, CD4, CD5, CD7, CD8, CD28, CD56, CD81, and CD117. In situ hybridization for EBV-encoded smalI RNA was negative and immunohistochemistry for Kaposi sarcoma herpesvirus (HHV8) confirmed the diagnosis of PEL. Our results confirm that flow cytometry bring useful data in the diagnosis of large-cell lymphomas involving body cavities. © 2018 International Clinical Cytometry Society.


Asunto(s)
Citometría de Flujo , Inmunofenotipificación , Linfoma de Efusión Primaria/diagnóstico , Humanos
15.
Expert Opin Pharmacother ; 19(12): 1327-1336, 2018 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-30101632

RESUMEN

INTRODUCTION: Cystic fibrosis is characterized by bacterial lung infection, a majority of adults being chronically infected with Pseudomonas aeruginosa. Treatment is a major challenge, with frequent courses of antibiotics contributing to antimicrobial resistance. New approaches are clearly required. Over the last few years, a major shift in our approach to treating CF has occurred with the availability of the first drugs targeting the CFTR protein and leading to improvements in lung function, weight gain and frequency of exacerbations. AREAS COVERED: There are emerging, but limited, data exploring the effect these drugs have on airway infections, some studies suggesting a beneficial impact. CFTR modulators probably possess very little direct antimicrobial activity, but both synergy with conventional antibiotics and alternative mechanisms of bacterial killing have been proposed. This article reviews the current published evidence. EXPERT OPINION: The picture is far from clear concerning the impact of CFTR modulators on lung infections. However, currently, such drugs restore CFTR function incompletely, are most commonly introduced when lung damage is already present, are not suitable for all CF patients and not reimbursed in some areas. Therefore, whatever their eventual anti-infective potential, we need to continue our search for effective anti-pseudomonal therapies for the foreseeable future.


Asunto(s)
Regulador de Conductancia de Transmembrana de Fibrosis Quística/uso terapéutico , Fibrosis Quística/tratamiento farmacológico , Infecciones por Pseudomonas/tratamiento farmacológico , Estudios Transversales , Fibrosis Quística/patología , Regulador de Conductancia de Transmembrana de Fibrosis Quística/farmacología , Humanos
16.
Br J Sociol ; 69(3): 647-669, 2018 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-28802052

RESUMEN

Why are some policies protested more than others? New data on protest against eight categories of taxation in twenty rich democracies from 1980 to 2010 reveal that economically and socially concentrated taxes are protested most, whereas taxes that confer entitlement to benefits are protested least. Other features of policy design often thought to affect the salience or visibility of costs are unimportant for explaining the frequency of protest. These findings overturn a folk theory that political sociology has inherited from classical political economy; clarify the conditions under which policy threats provoke protest; and shed light on how welfare states persist.


Asunto(s)
Actitud , Disentimientos y Disputas , Política , Política Pública/economía , Impuestos , Comercio/economía , Bases de Datos Factuales , Democracia , Europa (Continente) , Humanos , Bienestar Social/economía
17.
FEMS Microbiol Lett ; 364(14)2017 08 01.
Artículo en Inglés | MEDLINE | ID: mdl-28854668

RESUMEN

Pseudomonas aeruginosa opportunistically infects the airways of patients with cystic fibrosis and causes significant morbidity and mortality. Initial infection can often be eradicated though requires prompt detection and adequate treatment. Intermittent and then chronic infection occurs in the majority of patients. Better detection of P. aeruginosa infection using biomarkers may enable more successful eradication before chronic infection is established. In chronic infection P. aeruginosa adapts to avoid immune clearance and resist antibiotics via efflux pumps, ß-lactamase expression, reduced porins and switching to a biofilm lifestyle. The optimal treatment strategies for P. aeruginosa infection are still being established, and new antibiotic formulations such as liposomal amikacin, fosfomycin in combination with tobramycin and inhaled levofloxacin are being explored. Novel agents such as the alginate oligosaccharide OligoG, cysteamine, bacteriophage, nitric oxide, garlic oil and gallium may be useful as anti-pseudomonal strategies, and immunotherapy to prevent infection may have a role in the future. New treatments that target the primary defect in cystic fibrosis, recently licensed for use, have been associated with a fall in P. aeruginosa infection prevalence. Understanding the mechanisms for this could add further strategies for treating P. aeruginosa in future.


Asunto(s)
Antibacterianos/uso terapéutico , Fibrosis Quística/complicaciones , Inmunoterapia , Infecciones por Pseudomonas/complicaciones , Pseudomonas aeruginosa/efectos de los fármacos , Administración por Inhalación , Compuestos Alílicos/uso terapéutico , Antibacterianos/administración & dosificación , Biopelículas/efectos de los fármacos , Fibrosis Quística/tratamiento farmacológico , Fibrosis Quística/microbiología , Farmacorresistencia Bacteriana Múltiple , Humanos , Inmunoterapia/métodos , Infecciones por Pseudomonas/diagnóstico , Infecciones por Pseudomonas/microbiología , Pseudomonas aeruginosa/enzimología , Sulfuros/uso terapéutico , beta-Lactamasas/biosíntesis , beta-Lactamasas/genética
18.
Sensors (Basel) ; 14(11): 19926-44, 2014 Oct 24.
Artículo en Inglés | MEDLINE | ID: mdl-25347580

RESUMEN

This paper discusses the overall design and implementation of a video sensor for the detection of risky behaviors of car drivers near previously identified and georeferenced black spots. The main goal is to provide the driver with a visual audio alert that informs of the proximity of an area of high incidence of highway accidents only if their driving behavior could result in a risky situation. It proposes a video sensor for detecting and supervising driver behavior, its main objective being manual distractions, so hand driver supervision is performed. A GPS signal is also considered, the GPS information is compared with a database of global positioning Black Spots to determine the relative proximity of a risky area. The outputs of the video sensor and GPS sensor are combined to evaluate a possible risky behavior. The results are promising in terms of risk analysis in order to be validated for use in the context of the automotive industry as future work.


Asunto(s)
Accidentes de Tránsito/prevención & control , Conducción de Automóvil , Sistemas de Información Geográfica/instrumentación , Interpretación de Imagen Asistida por Computador/instrumentación , Imagenología Tridimensional/instrumentación , Fotograbar/instrumentación , Grabación en Video/instrumentación , Diseño de Equipo , Análisis de Falla de Equipo , Interpretación de Imagen Asistida por Computador/métodos , Reconocimiento de Normas Patrones Automatizadas/métodos , Procesamiento de Señales Asistido por Computador/instrumentación , Transductores
19.
Soc Sci Res ; 42(2): 347-60, 2013 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-23347481

RESUMEN

Previous research has argued that income inequality reduces people's trust in other people, and that declining social trust in the United States in recent decades has been due to rising levels of income inequality. Using multilevel models fitted to data from the General Social Survey, this paper substantially qualifies these arguments. We show that while people are less trusting in US states with higher income inequality, this association holds only cross-sectionally, not longitudinally; since the 1970s, states experiencing larger increases in inequality have not suffered systematically larger declines in trust. For counties, there is no statistically significant relationship either cross-sectionally or longitudinally. There is therefore only limited empirical support for the argument that inequality influences generalized social trust; and the declining trust of recent decades certainly cannot be attributed to rising inequality.

20.
J Robot Surg ; 2(3): 151-8, 2008 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-27628252

RESUMEN

The aims of this study were to test the face, content, and construct validities of a virtual-reality haptic arthroscopy simulator and to validate four assessment hypothesis. The participants in our study were 94 arthroscopists attending an international conference on arthroscopy. The interviewed surgeons had been performing arthroscopies for a mean of 8.71 years (σ = 6.94 years). We explained the operation, functionality, instructions for use, and the exercises provided by the simulator. They performed a trial exercise and then an exercise in which performance was recorded. After having using it, the arthroscopists answered a questionnaire. The simulator was classified as one of the best training methods (over phantoms), and obtained a mark of 7.10 out of 10 as an evaluation tool. The simulator was considered more useful for inexperienced surgeons than for surgeons with experience (mean difference 1.88 out of 10, P value < 0.001). The participants valued the simulator at 8.24 as a tool for learning skills, its fidelity at 7.41, the quality of the platform at 7.54, and the content of the exercises at 7.09. It obtained a global score of 7.82. Of the subjects, 30.8% said they would practise with the simulator more than 6 h per week. Of the surgeons, 89.4% affirmed that they would recommend the simulator to their colleagues. The data gathered support the first three hypotheses, as well as face and content validities. Results show statistically significant differences between experts and novices, thus supporting the construct validity, but studies with a larger sample must be carried out to verify this. We propose concrete solutions and an equation to calculate economy of movement. Analogously, we analyze competence measurements and propose an equation to provide a single measurement that contains them all and that, according to the surgeons' criteria, is as reliable as the judgment of experts observing the performance of an apprentice.

SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA
...