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2.
J Orthop Sci ; 25(4): 595-598, 2020 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-31285118

RESUMEN

BACKGROUND: Hip pathology can affect functions including sexual activity. Sex after hip replacement (SAHR) is an important subject for patients but rarely discussed. A conversation prior to surgery can be difficult to initiate, and appropriate advice is then not given. This study has set out to find how physicians approach the subject, and how patients would the like the subject to be addressed. Thus, device a process that ensures appropriate discussions take place prior to Total Hip Replacement (THR) in all patients. METHODS: Questionnaires were given to clinicians and patients. The clinicians' questionnaire asked how they dealt with the issue of SAHR. All patients below the age of 80 were asked how the issue was addressed, and how this could be improved. The aim of this study was twofold. Firstly, to address how SAHR should be approached, both by reviewing the clinicians present views and asking the patients their expectations. Secondly, to develop a process that will ensure patients' concerns are appropriately and consistently addressed prior to total hip replacement (THR). RESULTS: All 17 clinicians responded. None used any printed information to give to patients dealing with SAHR nor did they routinely discuss it with patients. 244/340 patients responded. Over 90% of patients wanted the surgeon to discuss sex after THR with them, and would be happy to be asked directly about the subject. CONCLUSION: Clinicians do not routinely raise the subject of SAHR with patients, who often wanted to know, but rarely asked. There is unease around the subject, and therefore there is a need to establish a process that ensures this discussion takes place prior to THR.


Asunto(s)
Artroplastia de Reemplazo de Cadera , Educación del Paciente como Asunto , Relaciones Médico-Paciente , Conducta Sexual , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Encuestas y Cuestionarios
3.
Eur J Clin Microbiol Infect Dis ; 38(6): 1087-1093, 2019 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-30783889

RESUMEN

Campylobacter diagnosis is hampered because many laboratories continue to use traditional stool culture, which is slow and suffers false-negative results. This large multi-site study used a composite reference method consisting of a new FDA-cleared immunoassay and four molecular techniques to compare to culture. Prospectively collected patient fecal specimens (1552) were first preliminarily categorized as positive or negative by traditional culture. All specimens were also tested by EIA, and any EIA-positive or culture-discrepant results were further characterized by 16S rRNA qPCR, eight species-specific PCR assays, bidirectional sequencing, and an FDA-cleared multiplex PCR panel. The five non-culture methods showed complete agreement on all positive and discrepant specimens which were then assigned as true-positive or true-negative specimens. Among 47 true-positive specimens, culture incorrectly identified 13 (28%) as negative, and 1 true-negative specimen as positive, for a sensitivity of 72.3%. Unexpectedly, among the true-positive specimens, 4 (8%) were the pathogenic species C. upsaliensis. Culture had a 30% false result rate compared to immunoassay and molecular methods. More accurate results lead to better diagnosis and treatment of suspected campylobacteriosis.


Asunto(s)
Técnicas Bacteriológicas/normas , Infecciones por Campylobacter/diagnóstico , Campylobacter/aislamiento & purificación , Técnicas de Diagnóstico Molecular/normas , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Campylobacter upsaliensis/aislamiento & purificación , Niño , Preescolar , Heces/microbiología , Femenino , Humanos , Inmunoensayo/normas , Lactante , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Sensibilidad y Especificidad , Adulto Joven
4.
Phys Rev Lett ; 118(18): 186401, 2017 May 05.
Artículo en Inglés | MEDLINE | ID: mdl-28524678

RESUMEN

Filling-enforced Dirac semimetals, or those required at specific fillings by the combination of crystalline and time-reversal symmetries, have been proposed in numerous materials. However, Dirac points in these materials are not generally robust against breaking or modifying time-reversal symmetry. We present a new class of two-dimensional Dirac semimetal protected by the combination of crystal symmetries and a special, antiferromagnetic time-reversal symmetry. Systems in this class of magnetic layer groups, while having broken time-reversal symmetry, still respect the operation of time-reversal followed by a half-lattice translation. In contrast to 2D time-reversal-symmetric Dirac semimetal phases, this magnetic Dirac phase is capable of hosting just a single isolated Dirac point at the Fermi level, one that can be stabilized solely by symmorphic crystal symmetries. We find that this Dirac point represents a new quantum critical point, existing at the boundary between Chern insulating, antiferromagnetic topological crystalline insulating, and trivial insulating phases, and we discuss its relationship with condensed matter fermion doubling theorems. We present density functional theoretic calculations which demonstrate the presence of these 2D magnetic Dirac points in FeSe monolayers and discuss the implications for engineering quantum phase transitions in these materials.

5.
Phys Rev Lett ; 115(12): 126803, 2015 Sep 18.
Artículo en Inglés | MEDLINE | ID: mdl-26431004

RESUMEN

Graphene is famous for being a host of 2D Dirac fermions. However, spin-orbit coupling introduces a small gap, so that graphene is formally a quantum spin Hall insulator. Here we present symmetry-protected 2D Dirac semimetals, which feature Dirac cones at high-symmetry points that are not gapped by spin-orbit interactions and exhibit behavior distinct from both graphene and 3D Dirac semimetals. Using a two-site tight-binding model, we construct representatives of three possible distinct Dirac semimetal phases and show that single symmetry-protected Dirac points are impossible in two dimensions. An essential role is played by the presence of nonsymmorphic space group symmetries. We argue that these symmetries tune the system to the boundary between a 2D topological and trivial insulator. By breaking the symmetries we are able to access trivial and topological insulators as well as Weyl semimetal phases.

6.
Phys Rev Lett ; 112(3): 036403, 2014 Jan 24.
Artículo en Inglés | MEDLINE | ID: mdl-24484151

RESUMEN

We report on a Dirac-like Fermi surface in three-dimensional bulk materials in a distorted spinel structure on the basis of density functional theory as well as tight-binding theory. The four examples we provide in this Letter are BiZnSiO4, BiCaSiO4, BiAlInO4, and BiMgSiO4. A necessary characteristic of these structures is that they contain a Bi lattice which forms a hierarchy of chainlike substructures, with consequences for both fundamental understanding and materials design.

7.
J Chem Phys ; 141(20): 204704, 2014 Nov 28.
Artículo en Inglés | MEDLINE | ID: mdl-25429954

RESUMEN

We calculate the shift current response, which has been identified as the dominant mechanism for the bulk photovoltaic effect, for the polar compounds LiAsS2, LiAsSe2, and NaAsSe2. We find that the magnitudes of the photovoltaic responses in the visible range for these compounds exceed the maximum response obtained for BiFeO3 by 10-20 times. We correlate the high shift current response with the existence of p states at both the valence and conduction band edges, as well as the dispersion of these bands, while also showing that high polarization is not a requirement. With low experimental band gaps of less than 2 eV and high shift current response, these materials have potential for use as bulk photovoltaics.

8.
Ergonomics ; 57(4): 503-10, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24588355

RESUMEN

Research using participant's self-reports has documented a link between red and danger. In this research, we used two different variants of a Stroop word evaluation task to test for the possibility of an implicit red-danger association using carefully controlled colour stimuli (equated on lightness and chroma). Experiment 1, using words as stimuli, yielded strong evidence of a link between red and danger, and weaker evidence of a green-safety association. Experiment 2, using symbols as stimuli, again yielded strong evidence of a link between red and danger; no green effects were observed. The findings were discussed in terms of the power and promise of red in signal communication.


Asunto(s)
Percepción de Color , Conducta Peligrosa , Simbolismo , Atención , Color , Femenino , Humanos , Masculino , Test de Stroop , Adulto Joven
9.
Br J Community Nurs ; 19(12): 585-91, 2014 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-25475672

RESUMEN

Incontinence-associated dermatitis (IAD) is a defined pathological entity and presents a significant burden for patients and health-care systems. The main objective of this evaluation was to test the efficacy and safety of a skin barrier cream in the management of uncomplicated IAD in elderly patients. Ten incontinent patients with mobility problems that presented with signs of IAD were included in the evaluation. The evaluation took place during a 2-week period. The product's efficacy was objectively evaluated in each patient with high-frequency ultrasound scans taken from the irritated skin compared with an ultrasound scan taken from normal adjacent (control) skin. Data analysis showed a statistical significance in favour of the capacity of the product to help reduce inflammatory signs. Photographic follow-up allowed correlation of ultrasound findings and clinical signs. The product was effective in treating the skin irritation and preventing further skin breakdown. There were no adverse events during the evaluation.


Asunto(s)
Fármacos Dermatológicos , Incontinencia Fecal/complicaciones , Enfermedades de la Piel/terapia , Terapia por Ultrasonido , Incontinencia Urinaria/complicaciones , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Enfermedades de la Piel/etiología
10.
Ther Innov Regul Sci ; 58(3): 520-527, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38366107

RESUMEN

BACKGROUND: Risk-based monitoring (RBM) and risk-based quality management (RBQM) offer a compelling approach to increase efficiency, speed and quality in clinical trials by prioritizing and mitigating risks related to essential safety and efficacy data. Since 2013, the FDA and EMA have encouraged the use of RBM/RBQM, however adoption has been slow with limited understanding of the barriers to adoption. METHODS: The Tufts Center for the Study of Drug Development conducted an online survey among pharmaceutical, biotechnology, and contract research organizations and gathered 206 responses on 32 distinct RBQM practices. RESULTS: On average, companies implemented RBQM in 57% of their clinical trials. Lower levels of adoption were observed among companies conducting fewer than 25 trials annually (48%) compared to those conducting more than 100 trials annually (63%). Primary barriers to adoption include lack of organizational knowledge and awareness, mixed perceptions of the value proposition of RBQM, and poor change management planning and execution. Insights into improving the level of adoption are discussed.


Asunto(s)
Ensayos Clínicos como Asunto , Gestión de Riesgos , Humanos , Encuestas y Cuestionarios , Estados Unidos , Industria Farmacéutica
11.
Ther Innov Regul Sci ; 58(3): 483-494, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38334868

RESUMEN

BACKGROUND: Central monitoring aims at improving the quality of clinical research by pro-actively identifying risks and remediating emerging issues in the conduct of a clinical trial that may have an adverse impact on patient safety and/or the reliability of trial results. This paper, focusing on statistical data monitoring (SDM), is the second of a series that attempts to quantify the impact of central monitoring in clinical trials. MATERIAL AND METHODS: Quality improvement was assessed in studies using SDM from a single large central monitoring platform. The analysis focused on a total of 1111 sites that were identified as at-risk by the SDM tests and for which the study teams conducted a follow-up investigation. These sites were taken from 159 studies conducted by 23 different clinical development organizations (including both sponsor companies and contract research organizations). Two quality improvement metrics were assessed for each selected site, one based on a site data inconsistency score (DIS, overall -log10 P-value of the site compared with all other sites) and the other based on the observed metric value associated with each risk signal. RESULTS: The SDM quality metrics showed improvement in 83% (95% CI, 80-85%) of the sites across therapeutic areas and study phases (primarily phases 2 and 3). In contrast, only 56% (95% CI, 41-70%) of sites showed improvement in 2 historical studies that did not use SDM during study conduct. CONCLUSION: The results of this analysis provide clear quantitative evidence supporting the hypothesis that the use of SDM in central monitoring is leading to improved quality in clinical trial conduct and associated data across participating sites.


Asunto(s)
Ensayos Clínicos como Asunto , Exactitud de los Datos , Mejoramiento de la Calidad , Humanos , Comités de Monitoreo de Datos de Ensayos Clínicos , Reproducibilidad de los Resultados , Seguridad del Paciente
12.
Ther Innov Regul Sci ; 58(3): 423-430, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38321191

RESUMEN

The past years have sharpened the industry's understanding of a Quality by Design (QbD) approach toward clinical trials. Using QbD encourages designing quality into a trial during the planning phase. The identification of Critical to Quality (CtQs) factors and specifically Critical Data and Processes (CD&Ps) is key to such a risk-based monitoring approach. A variable that allows monitoring the evolution of risk regarding the CD&Ps is called a Quality Tolerance Limit (QTL) parameter. These parameters are linked to the scientific question(s) of a trial and may identify the issues that can jeopardize the integrity of trial endpoints. This paper focuses on defining what QTL parameters are and providing general guidance on setting thresholds for these parameters allowing for the derivation of an acceptable range of the risk.


Asunto(s)
Ensayos Clínicos como Asunto , Humanos , Proyectos de Investigación , Control de Calidad
13.
Phys Rev Lett ; 110(5): 057201, 2013 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-23414042

RESUMEN

Here we predict the existence of a linear bulk spin photovoltaic effect, where spin currents are produced in antiferromagnetic materials as a response to linearly polarized light, and we describe the symmetry requirements for such a phenomenon to exist. This effect does not depend on spin-orbit effects or require inversion symmetry breaking, distinguishing it from previously explored methods. We propose that the physical mechanism is the nonlinear optical effect "shift current," and calculate from first principles the spin photocurrent for hematite and bismuth ferrite. We predict a significant response in these materials, with hematite being especially promising due to its availability, low band gap, lack of charge photocurrents, and negligible spin-orbit effect.

14.
Proc Inst Mech Eng H ; 227(2): 175-80, 2013 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-23513988

RESUMEN

Preparation of the proximal femur using incremental broaches to create the ideal cancellous bone envelope is an important technique to perfect in uncemented hip arthroplasty. To guide broaching adequacy and final implant position, the surgeon can use audible pitch changes produced by the femoral broach and definitive implant. The aim of this study was to characterise these pitch changes by analysing the sound spectra created by the first broach, last broach and implant using spectral analysis software. The last broach and implant introduction spectra demonstrated low-frequency (400-1200 Hz) spectral peaks that were not detected when using the first broach. These frequencies corresponded to the natural resonant frequency of a standing sound wave within the femoral bone canal (approximately 894 Hz) that was estimated using acoustic physics theory. The remaining spectral peaks were associated with transverse vibration modes produced by striking the metal broach handle and implant introducer and were a function of the constructs geometry and material properties.


Asunto(s)
Artroplastia de Reemplazo de Cadera/métodos , Fémur/fisiopatología , Fémur/cirugía , Prótesis de Cadera , Osteotomía/métodos , Espectrografía del Sonido/métodos , Cirugía Asistida por Computador/métodos , Artroplastia de Reemplazo de Cadera/instrumentación , Humanos , Reproducibilidad de los Resultados , Sensibilidad y Especificidad
15.
Ther Innov Regul Sci ; 57(2): 295-303, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-36269551

RESUMEN

BACKGROUND: Central monitoring, which typically includes the use of key risk indicators (KRIs), aims at improving the quality of clinical research by pro-actively identifying and remediating emerging issues in the conduct of a clinical trial that may have an adverse impact on patient safety and/or the reliability of trial results. However, there has to-date been a relative lack of direct quantitative evidence published supporting the claim that central monitoring actually leads to improved quality. MATERIAL AND METHODS: Nine commonly used KRIs were analyzed for evidence of quality improvement using data retrieved from a large central monitoring platform. A total of 212 studies comprising 1676 sites with KRI signals were used in the analysis, representing central monitoring activity from 23 different sponsor organizations. Two quality improvement metrics were assessed for each KRI, one based on a statistical score (p-value) and the other based on a KRI's observed value. RESULTS: Both KRI quality metrics showed improvement in a vast majority of sites (82.9% for statistical score, 81.1% for observed KRI value). Additionally, the statistical score and the observed KRI values improved, respectively by 66.1% and 72.4% on average towards the study average for those sites showing improvement. CONCLUSION: The results of this analysis provide clear quantitative evidence supporting the hypothesis that use of KRIs in central monitoring is leading to improved quality in clinical trial conduct and associated data across participating sites.


Asunto(s)
Benchmarking , Humanos , Reproducibilidad de los Resultados
16.
Ther Innov Regul Sci ; 57(4): 839-848, 2023 07.
Artículo en Inglés | MEDLINE | ID: mdl-36972010

RESUMEN

Since the release of ICH E6(R2), multiple efforts have been made to interpret the requirements and suggest ways of implementing quality tolerance limits (QTLs) alongside existing risk-based quality management methodologies. While these efforts have contributed positively to developing a common understanding of QTLs, some uncertainty remains regarding implementable approaches. In this article, we review the approaches taken by some leading biopharmaceutical companies, offering recommendations for how to make QTLs most effective, what makes them ineffective, and several case studies to illustrate these concepts. This includes how best to choose QTL parameters and thresholds for a given study, how to differentiate QTLs from key risk indicators, and how QTLs relate to critical-to-quality factors and the statistical design of the trials.


Asunto(s)
Productos Biológicos , Sitios de Carácter Cuantitativo , Gestión de Riesgos
17.
J Cachexia Sarcopenia Muscle ; 14(4): 1657-1669, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-37243418

RESUMEN

BACKGROUND: Rheumatoid arthritis (RA) is an autoimmune disease that affects the joints, leading to chronic synovial inflammation and local tissue destruction. Extra-articular manifestations may also occur, such as changes in body composition. Skeletal muscle wasting is often observed in patients with RA, but methods for assessing loss of muscle mass are expensive and not widely available. Metabolomic analysis has shown great potential for identifying changes in the metabolite profile of patients with autoimmune diseases. In this setting, urine metabolomic profiling in patients with RA may be a useful tool to identify skeletal muscle wasting. METHODS: Patients aged 40-70 years with RA have been recruited according to the 2010 ACR/EULAR classification criteria. Further, the Disease Activity Score in 28 joints using the C-reactive protein level (DAS28-CRP) determined the disease activity. The muscle mass was measured by Dual X-ray absorptiometry (DXA) to generate the appendicular lean mass index (ALMI) by summing the lean mass measurements for both arms and legs and dividing them by height squared (kg/height2 ). Finally, urine metabolomic analysis by 1 H nuclear magnetic resonance (1 H-NMR) spectroscopy was performed and the metabolomics data set analysed using the BAYESIL and MetaboAnalyst software packages. Principal component analysis (PCA) and partial least squares-discriminant analysis (PLS-DA) were applied to the 1 H-NMR data, followed by Spearman's correlation analysis. The combined receiver operating characteristic curve (ROC) was calculated, as well as the logistic regression analyses to establish a diagnostic model. The significance level at P < 0.05 was set for all analyses. RESULTS: The total set of subjects investigated included 90 patients with RA. Most patients were women (86.7%), with a mean age of 56.5 ± 7.3 years old and a median DAS28-CRP of 3.0 (IQR 1.0-3.0). Fifteen metabolites were identified in the urine samples with high variable importance in projection (VIP scores) by MetaboAnalyst. Of these, dimethylglycine (r = 0.205; P = 0.053), oxoisovalerate (r = -0.203; P = 0.055), and isobutyric acid (r = -0.249; P = 0.018) were significantly correlated with ALMI. Based on the low muscle mass (ALMI ≤6.0 kg/m2 for women and ≤8.1 kg/m2 for men) a diagnostic model have been established with dimethylglycine (area under the curve [AUC] = 0.65), oxoisovalerate (AUC = 0.49), and isobutyric acid (AUC = 0.83) with significant sensitivity and specificity. CONCLUSIONS: Isobutyric acid, oxoisovalerate, and dimethylglycine from urine samples were associated with low skeletal muscle mass in patients with RA. These findings suggest that this group of metabolites may be further tested as biomarkers for identification of skeletal muscle wasting.


Asunto(s)
Artritis Reumatoide , Masculino , Humanos , Femenino , Persona de Mediana Edad , Artritis Reumatoide/diagnóstico , Biomarcadores/metabolismo , Atrofia Muscular/patología , Metabolómica/métodos , Inflamación/patología , Músculo Esquelético/patología
18.
J Med Chem ; 66(6): 4025-4044, 2023 03 23.
Artículo en Inglés | MEDLINE | ID: mdl-36912866

RESUMEN

Bruton's tyrosine kinase (BTK) plays an essential role in B-cell receptor (BCR)-mediated signaling as well as the downstream signaling pathway for Fc receptors (FcRs). Targeting BTK for B-cell malignancies by interfering with BCR signaling has been clinically validated by some covalent inhibitors, but suboptimal kinase selectivity may lead to some adverse effects, which also makes the clinical development of autoimmune disease therapy more challenging. The structure-activity relationship (SAR) starting from zanubrutinib (BGB-3111) leads to a series of highly selective BTK inhibitors, in which BGB-8035 is located in the ATP binding pocket and has similar hinge binding to ATP but exhibits high selectivity over other kinases (EGFR, Tec, etc.). With an excellent pharmacokinetic profile as well as demonstrated efficacy studies in oncology and autoimmune disease models, BGB-8035 has been declared a preclinical candidate. However, BGB-8035 showed an inferior toxicity profile compared to that of BGB-3111.


Asunto(s)
Enfermedades Autoinmunes , Neoplasias , Humanos , Agammaglobulinemia Tirosina Quinasa , Relación Estructura-Actividad , Enfermedades Autoinmunes/tratamiento farmacológico , Neoplasias/tratamiento farmacológico , Adenosina Trifosfato , Inhibidores de Proteínas Quinasas/uso terapéutico , Inhibidores de Proteínas Quinasas/farmacocinética
19.
bioRxiv ; 2023 Nov 22.
Artículo en Inglés | MEDLINE | ID: mdl-38076895

RESUMEN

SARS-CoV-2 continues to pose a global threat, and current vaccines, while effective against severe illness, fall short in preventing transmission. To address this challenge, there's a need for vaccines that induce mucosal immunity and can rapidly control the virus. In this study, we demonstrate that a single immunization with a novel gorilla adenovirus-based vaccine (GRAd) carrying the pre-fusion stabilized Spike protein (S-2P) in non-human primates provided protective immunity for over one year against the BA.5 variant of SARS-CoV-2. A prime-boost regimen using GRAd followed by adjuvanted S-2P (GRAd+S-2P) accelerated viral clearance in both the lower and upper airways. GRAd delivered via aerosol (GRAd(AE)+S-2P) modestly improved protection compared to its matched intramuscular regimen, but showed dramatically superior boosting by mRNA and, importantly, total virus clearance in the upper airway by day 4 post infection. GrAd vaccination regimens elicited robust and durable systemic and mucosal antibody responses to multiple SARS-CoV-2 variants, but only GRAd(AE)+S-2P generated long-lasting T cell responses in the lung. This research underscores the flexibility of the GRAd vaccine platform to provide durable immunity against SARS-CoV-2 in both the lower and upper airways.

20.
Phys Rev Lett ; 109(23): 236601, 2012 Dec 07.
Artículo en Inglés | MEDLINE | ID: mdl-23368233

RESUMEN

We compute the bulk photovoltaic effect (BPVE) in BiFeO(3) using first-principles shift current theory, finding good agreement with experimental results. Furthermore, we reconcile apparently contradictory observations: by examining the contributions of all photovoltaic response tensor components and accounting for the geometry and ferroelectric domain structure of the experimental system, we explain the apparent lack of BPVE response in striped polydomain samples that is at odds with the significant response observed in monodomain samples. We reveal that the domain-wall-driven response in striped polydomain samples is partially mitigated by the BPVE, suggesting that enhanced efficiency could be obtained in materials with cooperative rather than antagonistic interaction between the two mechanisms.

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