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1.
Phys Rev Lett ; 126(9): 091301, 2021 Mar 05.
Artículo en Inglés | MEDLINE | ID: mdl-33750173

RESUMEN

We report on a search for nuclear recoil signals from solar ^{8}B neutrinos elastically scattering off xenon nuclei in XENON1T data, lowering the energy threshold from 2.6 to 1.6 keV. We develop a variety of novel techniques to limit the resulting increase in backgrounds near the threshold. No significant ^{8}B neutrinolike excess is found in an exposure of 0.6 t×y. For the first time, we use the nondetection of solar neutrinos to constrain the light yield from 1-2 keV nuclear recoils in liquid xenon, as well as nonstandard neutrino-quark interactions. Finally, we improve upon world-leading constraints on dark matter-nucleus interactions for dark matter masses between 3 and 11 GeV c^{-2} by as much as an order of magnitude.

2.
S Afr J Surg ; 58(2): 105, 2020 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-32644315

RESUMEN

BACKGROUND: Successful percutaneous nephrolithotomy (PCNL) relies on a technically challenging, precise needle puncture of the renal collecting system. We aimed to compare, in an ex vivo model, the use of a real time image guidance system (the SabreSource™) and a mechanical stabilising device with conventional manual techniques for the accuracy of needle placement. METHODS: The SabreSource™ system (Minrad International Inc.; New York, USA) is a real time image guidance system. The system platform is mounted on a C-arm fluoroscope. It employs targeting cross hairs on the fluoroscopic image that can be easily positioned to target the desired renal calyx. The system directs a visible laser beam onto the patient which is precisely aligned with the cross hairs on the fluoroscopic image. This provides the correct "bull's-eye" angle of approach to the calyx, even after the x-ray source is turned off. The locator then stabilises the needle in the "bull's-eye" position so that only screening for depth is required. Objective assessment using a simulated PCNL puncture was performed by 7 urologic trainees on a kidney phantom with and without using the SabreSource™. Fluoroscopy screening time (FST) and amount of radiation (mGy) used to achieve successful puncture were compared. RESULTS: Simulated PCNL puncture was quicker and resulted in reduced radiation exposure when the apparatus was used. The mean FST for traditional "bull's-eye" vs SabreSource™ puncture was 17 vs 5 seconds (p = 0.01), and the mean radiation exposure to puncture was 0.7 vs 0.2 mGy (p = 0.03), respectively. CONCLUSION: The SabreSource™ is a novel assistant to achieving successful PCNL puncture. In combination with "the locator" the preliminary in vitro testing suggests that the device reduces fluoroscopy exposure and is quicker. The device warrants further evaluation in the clinical setting.


Asunto(s)
Cálculos Renales/cirugía , Túbulos Renales Colectores/cirugía , Nefrolitotomía Percutánea/instrumentación , Fantasmas de Imagen , Sistemas de Computación , Fluoroscopía , Humanos , Cálices Renales/cirugía , Punciones/instrumentación , Cirugía Asistida por Computador/instrumentación
3.
J Intellect Disabil Res ; 63(12): 1391-1400, 2019 12.
Artículo en Inglés | MEDLINE | ID: mdl-31397022

RESUMEN

BACKGROUND: The development of a nurse-led approach to managing epilepsy in adults with an intellectual disability (ID) offers the potential of improved outcomes and lower costs of care. We undertook a cluster randomised trial to assess the impact on costs and outcomes of the provision of ID nurses working to a designated epilepsy nurse competency framework. Here, we report the impact of the intervention on costs. METHOD: Across the United Kingdom, eight sites randomly allocated to the intervention recruited 184 participants and nine sites allocated to treatment as usual recruited 128 participants. Cost and outcome data were collected mainly by telephone interview at baseline and after 6 months. Total costs at 6 months were compared from the perspective of health and social services and society, with adjustments for pre-specified participant and cluster characteristics at baseline including costs. Missing data were imputed using multiple imputation. Uncertainty was quantified by bootstrapping. RESULTS: The intervention was associated with lower per participant costs from a health and social services perspective of -£357 (2014/2015 GBP) (95% confidence interval -£986, £294) and from a societal perspective of -£631 (95% confidence interval -£1473, £181). Results were not sensitive to the exclusion of accommodation costs. CONCLUSIONS: Our findings suggest that the competency framework is unlikely to increase the cost of caring for people with epilepsy and ID and may reduce costs.


Asunto(s)
Competencia Clínica , Servicios de Salud Comunitaria , Epilepsia/terapia , Costos de la Atención en Salud , Discapacidad Intelectual/terapia , Enfermeras y Enfermeros , Grupo de Atención al Paciente , Evaluación de Procesos, Atención de Salud , Adulto , Comorbilidad , Epilepsia/epidemiología , Humanos , Discapacidad Intelectual/epidemiología
4.
Phys Rev Lett ; 122(14): 141301, 2019 Apr 12.
Artículo en Inglés | MEDLINE | ID: mdl-31050482

RESUMEN

We report the first experimental results on spin-dependent elastic weakly interacting massive particle (WIMP) nucleon scattering from the XENON1T dark matter search experiment. The analysis uses the full ton year exposure of XENON1T to constrain the spin-dependent proton-only and neutron-only cases. No significant signal excess is observed, and a profile likelihood ratio analysis is used to set exclusion limits on the WIMP-nucleon interactions. This includes the most stringent constraint to date on the WIMP-neutron cross section, with a minimum of 6.3×10^{-42} cm^{2} at 30 GeV/c^{2} and 90% confidence level. The results are compared with those from collider searches and used to exclude new parameter space in an isoscalar theory with an axial-vector mediator.

5.
Phys Rev Lett ; 122(7): 071301, 2019 Feb 22.
Artículo en Inglés | MEDLINE | ID: mdl-30848617

RESUMEN

We present first results on the scalar coupling of weakly interacting massive particles (WIMPs) to pions from 1 t yr of exposure with the XENON1T experiment. This interaction is generated when the WIMP couples to a virtual pion exchanged between the nucleons in a nucleus. In contrast to most nonrelativistic operators, these pion-exchange currents can be coherently enhanced by the total number of nucleons and therefore may dominate in scenarios where spin-independent WIMP-nucleon interactions are suppressed. Moreover, for natural values of the couplings, they dominate over the spin-dependent channel due to their coherence in the nucleus. Using the signal model of this new WIMP-pion channel, no significant excess is found, leading to an upper limit cross section of 6.4×10^{-46} cm^{2} (90% confidence level) at 30 GeV/c^{2} WIMP mass.

6.
BMJ Support Palliat Care ; 9(2): 189-196, 2019 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-26817793

RESUMEN

BACKGROUND: Advance care planning (ACP) encompasses both verbal and written communications expressing preferences for future health and personal care and helps prepare people for healthcare decision-making in times of medical crisis. Healthcare systems are increasingly promoting ACP as a way to inform medical decision-making, but it is not clear how public engagement in ACP activities is changing over time. METHODS: Raw data from 3 independently conducted public polls on ACP engagement, in the same Canadian province, were analysed to assess whether participation in ACP activities changed over 6 years. RESULTS: Statistically significant increases were observed between 2007 and 2013 in: recognising the definition of ACP (54.8% to 80.3%, OR 3.37 (95% CI 2.68 to 4.24)), discussions about healthcare preferences with family (48.4% to 59.8%, OR 1.41 (95% CI 1.17 to 1.69)) and with healthcare providers (9.1% to 17.4%, OR 1.98 (95% CI 1.51 to 2.59)), written ACP plans (21% to 34.6%, OR 1.77 (95% CI 1.45 to 2.17)) and legal documentation (23.4% to 42.7%, OR 2.13 (95% CI 1.75 to 2.59)). These remained significant after adjusting for age, education and self-rated health status. CONCLUSIONS: ACP engagement increased over time, although the overall frequency remains low in certain elements such as discussing ACP with healthcare providers. We discuss factors that may be responsible for the increase and provide suggestions for healthcare systems or other public bodies seeking to stimulate engagement in ACP.


Asunto(s)
Planificación Anticipada de Atención/estadística & datos numéricos , Planificación Anticipada de Atención/tendencias , Participación de la Comunidad/estadística & datos numéricos , Participación de la Comunidad/tendencias , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Alberta , Femenino , Predicción , Humanos , Masculino , Persona de Mediana Edad , Adulto Joven
7.
Phys Rev Lett ; 121(11): 111302, 2018 Sep 14.
Artículo en Inglés | MEDLINE | ID: mdl-30265108

RESUMEN

We report on a search for weakly interacting massive particles (WIMPs) using 278.8 days of data collected with the XENON1T experiment at LNGS. XENON1T utilizes a liquid xenon time projection chamber with a fiducial mass of (1.30±0.01) ton, resulting in a 1.0 ton yr exposure. The energy region of interest, [1.4,10.6] keV_{ee} ([4.9,40.9] keV_{nr}), exhibits an ultralow electron recoil background rate of [82_{-3}^{+5}(syst)±3(stat)] events/(ton yr keV_{ee}). No significant excess over background is found, and a profile likelihood analysis parametrized in spatial and energy dimensions excludes new parameter space for the WIMP-nucleon spin-independent elastic scatter cross section for WIMP masses above 6 GeV/c^{2}, with a minimum of 4.1×10^{-47} cm^{2} at 30 GeV/c^{2} and a 90% confidence level.

8.
J Neonatal Perinatal Med ; 8(3): 199-205, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26485552

RESUMEN

OBJECTIVE: To evaluate the nutritional impact of a feed-holding guideline during transfusion for infants <32 weeks gestation. STUDY DESIGN: A pre-/post-interventional study was conducted after introduction of a guideline to hold feeds during transfusion. Demographic variables in addition to nutritional outcomes were collected on all infants admitted within 48 hours of birth with gestational age <32 weeks. Data was collected during a 6 month period pre-intervention and the 6 month period post-intervention. RESULTS: There were 145 eligible infants. Mean birth weight and gestational age were similar in both periods. In total, 98 infants received transfusions, and 82 of those had an active feeding order prior to at least one transfusion. Total transfusions per infant and transfusions ordered while an infant had active feeding orders were similar in both periods. Time to full feedings was decreased post-intervention (p <  0.001). Weight at 34 weeks, incidence of second IV placement, additional IV fluid use, and hypoglycemia were similar between groups.Of 593 total transfusions, 207 were ordered while an infant had an active order for enteral nutrition. Pre-intervention, 64% of transfusions had feeds held during transfusion. Post-intervention, 87% of transfusions had feeds held during transfusion. Feeds were held more often (p <  0.001) and for a shorter duration (p = 0.005) in the post-intervention group. CONCLUSION: Implementing a guideline standardizing feeding practices during transfusions in premature infants increases standardization of care and results in decreased variability in practice. Adverse nutritional consequences were not found after the introduction of the routine practice of holding feedings during transfusion in preterm infants.


Asunto(s)
Nutrición Enteral/métodos , Transfusión de Eritrocitos , Recién Nacido de muy Bajo Peso , Cuidado Intensivo Neonatal/métodos , Privación de Tratamiento/estadística & datos numéricos , Estudios de Seguimiento , Humanos , Recién Nacido , Recien Nacido Prematuro
9.
Curr Oncol ; 22(4): e237-45, 2015 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-26300673

RESUMEN

BACKGROUND: Advance care planning (acp) is an important process in health care today. How to prospectively identify potential local barriers and facilitators to uptake of acp across a complex, multi-sector, publicly funded health care system and how to develop specific mitigating strategies have not been well characterized. METHODS: We surveyed a convenience sample of clinical and administrative health care opinion leaders across the province of Alberta to characterize system-specific barriers and facilitators to uptake of acp. The survey was based on published literature about the barriers to and facilitators of acp and on the Michie Theoretical Domains Framework. RESULTS: Of 88 surveys, 51 (58%) were returned. The survey identified system-specific barriers that could challenge uptake of acp. The factors were categorized into four main domains. Three examples of individual system-specific barriers were "insufficient public engagement and misunderstanding," "conflict among different provincial health service initiatives," and "lack of infrastructure." Local system-specific barriers and facilitators were subsequently explored through a semi-structured informal discussion group involving key informants. The group identified approaches to mitigate specific barriers. CONCLUSIONS: Uptake of acp is a priority for many health care systems, but bringing about change in multi-sector health care systems is complex. Identifying system-specific barriers and facilitators to the uptake of innovation are important elements of successful knowledge translation. We developed and successfully used a simple and inexpensive process to identify local system-specific barriers and enablers to uptake of acp, and to identify specific mitigating strategies.

10.
Eur J Clin Microbiol Infect Dis ; 34(9): 1823-6, 2015 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-26071000

RESUMEN

Methicillin-resistant Staphylococcus aureus (MRSA) is an important human pathogen, and colonisation with this organism can result in localised or systemic infections which may be fatal. One hundred in-patients admitted to a London teaching hospital and 100 out-patients attending prosthetic dentistry clinics were recruited into this study. Of the 100 out-patients, 27 % harboured S. aureus on their dentures, compared to 33 % of in-patients. Only one out-patient had MRSA colonising their dentures whereas 12 % of the in-patients harboured MRSA. The median total bacterial count of the denture plaque samples was 6.2 × 10(7) cfu/sample and 6.9 × 10(7) cfu/sample for the out-patient and in-patient populations, respectively. In most instances, where present, S. aureus comprised less than 1 % of the total viable denture microbiota. Phage typing demonstrated that EMRSA-15 and non-typeable strains were harboured on dentures. The results of this study have revealed that dentures are a potential reservoir of MRSA and so account should be taken of these findings when planning decontamination procedures for elimination of this pathogen.


Asunto(s)
Dentaduras/microbiología , Staphylococcus aureus Resistente a Meticilina/aislamiento & purificación , Infecciones Estafilocócicas/epidemiología , Carga Bacteriana , Tipificación de Bacteriófagos , Humanos , Pacientes Internos , Pacientes Ambulatorios , Infecciones Estafilocócicas/microbiología
11.
AJNR Am J Neuroradiol ; 36(1): 188-93, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-25169927

RESUMEN

BACKGROUND AND PURPOSE: Neurologic morbidity remains high in neonates with perinatal hypoxic-ischemic injury despite therapeutic hypothermia. DTI provides qualitative and quantitative information about the microstructure of the brain, and a near-infrared spectroscopy index can assess cerebrovascular autoregulation. We hypothesized that lower ADC values would correlate with worse autoregulatory function. MATERIALS AND METHODS: Thirty-one neonates with hypoxic-ischemic injury were enrolled. ADC scalars were measured in 27 neonates (age range, 4-15 days) in the anterior and posterior centrum semiovale, basal ganglia, thalamus, posterior limb of the internal capsule, pons, and middle cerebellar peduncle on MRI obtained after completion of therapeutic hypothermia. The blood pressure range of each neonate with the most robust autoregulation was identified by using a near-infrared spectroscopy index. Autoregulatory function was measured by blood pressure deviation below the range with optimal autoregulation. RESULTS: In neonates who had MRI on day of life ≥10, lower ADC scalars in the posterior centrum semiovale (r = -0.87, P = .003, n = 9) and the posterior limb of the internal capsule (r = -0.68, P = .04, n = 9) correlated with blood pressure deviation below the range with optimal autoregulation during hypothermia. Lower ADC scalars in the basal ganglia correlated with worse autoregulation during rewarming (r = -0.71, P = .05, n = 8). CONCLUSIONS: Blood pressure deviation from the optimal autoregulatory range may be an early biomarker of injury in the posterior centrum semiovale, posterior limb of the internal capsule, and basal ganglia. Optimizing blood pressure to support autoregulation may decrease the risk of brain injury in cooled neonates with hypoxic-ischemic injury.


Asunto(s)
Lesiones Encefálicas/fisiopatología , Homeostasis/fisiología , Hipoxia-Isquemia Encefálica/fisiopatología , Presión Sanguínea , Encéfalo/fisiopatología , Lesiones Encefálicas/etiología , Lesiones Encefálicas/prevención & control , Circulación Cerebrovascular/fisiología , Femenino , Humanos , Hipotermia Inducida , Hipoxia-Isquemia Encefálica/complicaciones , Hipoxia-Isquemia Encefálica/terapia , Recién Nacido , Imagen por Resonancia Magnética , Masculino , Espectroscopía Infrarroja Corta
12.
J Curr Glaucoma Pract ; 8(2): 63-6, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-26997811

RESUMEN

PURPOSE: Observations made during glaucoma filtering surgery (trabeculectomy) suggest variability in the thickness of the bulbar conjunctiva and Tenon's layers between individuals. We propose that this could infuence the final bleb morphology and function. We designed a pilot study to assess this using optical coherence tomography (OCT) to measure bulbar conjunctival and Tenon's layer thickness. MATERIALS AND METHODS: A total of 67 eyes of 48 individuals were scanned using an optovue Mode RT100 version 2.0 OCT machine. Cross-line CAM-L scans were taken and the com bined bulbar conjunctival and Tenon's layer thickness was measured 3 mm above the superior limbus. Conjunctival and Tenon's layers appeared as a hyper-refective section as opposed to the hypo refective underlying sclera. Measurements were taken using the inbuilt review software. RESULTS: The age ranged from 23 to 91 years. There were 20 mal e s and 28 females. The mean conjunctival and Tenon's layer thick ness was 393 ± 67 microns (mean ± SD) ranging from 194 to 573 microns. CONCLUSION: Optical coherence tomography conjunctival and Tenon's layer thickness measurements appear to vary significantly between individuals. We postulate that this could infuence the final bleb morphology and may predict the risk of bleb encapsulation and failure or thin avascular blebs. Further assessment could establish cut-offs on which patients should receive intraoperative antimetabolites and/or Tenon's layer excision. How to cite this article: Howlett J, Vahdani K, Rossiter J. Bulbar Conjunctival and Tenon's Layer Thickness Measurement using Optical Coherence Tomography. J Curr Glaucoma Pract 2014;8(2):63-66.

13.
N Engl J Med ; 365(1): 32-43, 2011 Jul 07.
Artículo en Inglés | MEDLINE | ID: mdl-21732835

RESUMEN

BACKGROUND: Nesiritide is approved in the United States for early relief of dyspnea in patients with acute heart failure. Previous meta-analyses have raised questions regarding renal toxicity and the mortality associated with this agent. METHODS: We randomly assigned 7141 patients who were hospitalized with acute heart failure to receive either nesiritide or placebo for 24 to 168 hours in addition to standard care. Coprimary end points were the change in dyspnea at 6 and 24 hours, as measured on a 7-point Likert scale, and the composite end point of rehospitalization for heart failure or death within 30 days. RESULTS: Patients randomly assigned to nesiritide, as compared with those assigned to placebo, more frequently reported markedly or moderately improved dyspnea at 6 hours (44.5% vs. 42.1%, P=0.03) and 24 hours (68.2% vs. 66.1%, P=0.007), but the prespecified level for significance (P≤0.005 for both assessments or P≤0.0025 for either) was not met. The rate of rehospitalization for heart failure or death from any cause within 30 days was 9.4% in the nesiritide group versus 10.1% in the placebo group (absolute difference, -0.7 percentage points; 95% confidence interval [CI], -2.1 to 0.7; P=0.31). There were no significant differences in rates of death from any cause at 30 days (3.6% with nesiritide vs. 4.0% with placebo; absolute difference, -0.4 percentage points; 95% CI, -1.3 to 0.5) or rates of worsening renal function, defined by more than a 25% decrease in the estimated glomerular filtration rate (31.4% vs. 29.5%; odds ratio, 1.09; 95% CI, 0.98 to 1.21; P=0.11). CONCLUSIONS: Nesiritide was not associated with an increase or a decrease in the rate of death and rehospitalization and had a small, nonsignificant effect on dyspnea when used in combination with other therapies. It was not associated with a worsening of renal function, but it was associated with an increase in rates of hypotension. On the basis of these results, nesiritide cannot be recommended for routine use in the broad population of patients with acute heart failure. (Funded by Scios; ClinicalTrials.gov number, NCT00475852.).


Asunto(s)
Disnea/tratamiento farmacológico , Insuficiencia Cardíaca/tratamiento farmacológico , Natriuréticos/uso terapéutico , Péptido Natriurético Encefálico/uso terapéutico , Readmisión del Paciente/estadística & datos numéricos , Enfermedad Aguda , Anciano , Método Doble Ciego , Disnea/etiología , Femenino , Insuficiencia Cardíaca/complicaciones , Insuficiencia Cardíaca/mortalidad , Humanos , Hipotensión/inducido químicamente , Análisis de Intención de Tratar , Enfermedades Renales/etiología , Masculino , Persona de Mediana Edad , Natriuréticos/efectos adversos , Péptido Natriurético Encefálico/efectos adversos , Recurrencia
14.
Artículo en Inglés | MEDLINE | ID: mdl-20672203

RESUMEN

The feasibility of using a retailer fidelity card scheme to estimate food additive intake was investigated using the Swiss retailer MIGROS's Cumulus Card and the example of the food colour Sunset Yellow (E 110). Information held within the card scheme was used to identify a sample of households purchasing foods containing Sunset Yellow over a 15 day period. A sample of 1204 households was selected for interview, of which 830 households were retained in the study following interview. Interviews were conducted to establish household structure, patterns of consumption by different individuals within the household, and the proportion of foods containing Sunset Yellow habitually purchased at the retailer and/or consumed outside the home. Information provided by the retailer on levels of Sunset Yellow in the foods was combined with the information obtained at interview to calculate the per-capita intake of Sunset Yellow by members of participating households. More than 99% of consumers (n = 1902) of foods containing Sunset Yellow were estimated to consume less than 1 mg Sunset Yellow kg(-1) body weight day(-1). The method proved to be a simple and resource-efficient approach to estimate food additive intake on the basis of actual consumer behaviour and thus reports results more closely related to the actual consumption of foods by individuals.


Asunto(s)
Compuestos Azo/administración & dosificación , Encuestas sobre Dietas/métodos , Aditivos Alimentarios/administración & dosificación , Mercadotecnía/métodos , Compuestos Azo/economía , Dieta/economía , Composición Familiar , Estudios de Factibilidad , Femenino , Aditivos Alimentarios/economía , Colorantes de Alimentos/administración & dosificación , Colorantes de Alimentos/economía , Humanos , Masculino , Suiza
15.
Can J Cardiol ; 26(1): 37-41, 2010 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-20101356

RESUMEN

BACKGROUND: In October 2006, federal funding was announced for the development of a national strategy to fight cardiovascular disease (CVD) in Canada. The comprehensive, independent, stakeholder-driven Canadian Heart Health Strategy and Action Plan (CHHS-AP) was delivered to the Minister of Health on February 24, 2009. OBJECTIVES: The mandate of CHHS-AP Theme Working Group (TWG) 6 was to identify the optimal chronic disease management model that incorporated timely access to rehabilitation services and end-of-life planning and care. The purpose of the present paper was to provide an overview of worldwide approaches to CVD and cardiac rehabilitation (CR) strategies and recommendations for CR care in Canada, within the context of the well-known Chronic Care Model (CCM). A separate paper will address end-of-life issues in CVD. METHODS: TWG 6 was composed of content representatives, primary care representatives and patients. Input in the area of Aboriginal and indigenous cardiovascular health was obtained through individual expert consultation. Information germane to the present paper was gathered from international literature and best practice guidelines. The CCM principles were discussed and agreed on by all. Prioritization of recommendations and overall messaging was discussed and decided on within the entire TWG. The full TWG report was presented to the CHHS-AP Steering Committee and was used to inform the recommendations of the CHHS-AP. RESULTS: Specific actionable recommendations for CR are made in accordance with the key principles of the CCM. CONCLUSIONS: The present CR blueprint, as part of the CHHS-AP, will be a first step toward reducing the health care burden of CVD in Canada.


Asunto(s)
Rehabilitación Cardiaca , Atención a la Salud/organización & administración , Modelos Organizacionales , Canadá , Manejo de la Enfermedad , Humanos , Garantía de la Calidad de Atención de Salud
16.
Food Chem Toxicol ; 46(1): 9-33, 2008 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-17950974

RESUMEN

The role of post-market monitoring (PMM) in the safety assessment of novel foods is critically discussed in order to derive guidelines as to in which situations the application of PMM might be warranted. Available data sources on food consumption and health status, and the methodologies for generating such data are reviewed. The paper suggests improvements to make them more applicable for PMM purposes. It is concluded that any PMM programme must be a hypothesis-driven scientific exercise. PMM can have a role as a complement to, but not as a replacement for, a comprehensive pre-market safety assessment. Its use may be appropriate to confirm that product use is as predicted in the pre-market assessment; to provide reassurance that effects observed in the pre-market assessment occur with no greater frequency or intensity in the post-market phase than anticipated; and to investigate the significance of any adverse effects reported by consumers after market-launch. However PMM is insufficiently powerful to test the hypothesis that any effects seen in the pre-market assessment are absent in the post-market phase. Current methodologies place limitations on what PMM can achieve. PMM should only be used when triggered by or when the focus is on specific evidence-based questions.


Asunto(s)
Alimentos/normas , Aspartame/efectos adversos , Ácidos Grasos/efectos adversos , Abastecimiento de Alimentos/normas , Abastecimiento de Alimentos/estadística & datos numéricos , Humanos , Fitosteroles/efectos adversos , Plantas Modificadas Genéticamente/efectos adversos , Sacarosa/efectos adversos , Sacarosa/análogos & derivados , Edulcorantes/efectos adversos
17.
Can J Cardiol ; 22(9): 749-54, 2006 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-16835668

RESUMEN

Heart failure affects over 500,000 Canadians, and 50,000 new patients are diagnosed each year. The mortality remains staggering, with a five-year age-adjusted rate of 45%. Disease management programs for heart failure patients have been associated with improved outcomes, the use of evidence-based therapies, improved quality of care, and reduced costs, mortality and hospitalizations. Currently, national benchmarks and targets for access to care for cardiovascular procedures or office consultations do not exist. The present paper summarizes the currently available data, particularly focusing on the risk of adverse events as a function of waiting time, as well as on the identification of gaps in existing data on heart failure. Using best evidence and expert consensus, the present article also focuses on timely access to care for acute and chronic heart failure, including timely access to heart failure disease management programs and physician care (heart failure specialists, cardiologists, internists and general practitioners).


Asunto(s)
Accesibilidad a los Servicios de Salud , Insuficiencia Cardíaca/terapia , Selección de Paciente , Estudios de Seguimiento , Humanos , Ensayos Clínicos Controlados Aleatorios como Asunto , Factores de Riesgo , Factores de Tiempo
18.
Biomaterials ; 25(5): 823-33, 2004 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-14609671

RESUMEN

Diamond ATR FTIR has been used to quantify light catalysed polymerisation and polyacid neutralisation rates in various glass ionomer cements (GIC), resin-modified GICs (RMGIC) and compomers. At 150s after the start of light exposure, levels of methacrylate polymerisation on the lower surfaces of 1mm thick specimens were 97% and 98% for the RMGIC, Vitremer and Fuji II LC and 47% and 37% for the compomers, Compoglass and Dyract. After light exposure, polymerisation rates for the compomers decreased linearly with inverse time. By 50,000s Compoglass and Dyract were 62% and 51% polymerised. Initial rate of polyacid neutralisation in the GIC Shofu HIFI was 0.32 times that of Fuji IX GIC. Those in Vitremer, Fuji II LC, Compoglass and Dyract were 0.16, 0.09, 0.004 and 0.004 times that of Fuji IX. Excluding short initial periods, log of neutralisation rates decreased linearly with log-time. Average gradients were -1.35 for the GIC, -0.80 for the RMGIC and -0.59 for the compomers. By 50,000s, polyacid salt concentrations for the RMGIC and compomers were 0.41 and 0.016 times that of the GIC. Reaction mechanisms have been discussed and used to help interpret material mechanical properties, fluoride release rates and adhesion to tooth structure.


Asunto(s)
Compómeros/química , Restauración Dental Permanente/instrumentación , Cementos de Ionómero Vítreo/química , Ensayo de Materiales/métodos , Polímeros/química , Cementos de Resina/química , Espectroscopía Infrarroja por Transformada de Fourier/métodos , Compómeros/análisis , Compómeros/efectos de la radiación , Restauración Dental Permanente/métodos , Estética Dental , Cementos de Ionómero Vítreo/análisis , Cementos de Ionómero Vítreo/efectos de la radiación , Concentración de Iones de Hidrógeno , Cinética , Luz , Conformación Molecular , Cementos de Resina/análisis , Cementos de Resina/efectos de la radiación
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