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1.
Behav Res Methods ; 56(3): 1244-1259, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-37296324

RESUMEN

Measures of face-identification proficiency are essential to ensure accurate and consistent performance by professional forensic face examiners and others who perform face-identification tasks in applied scenarios. Current proficiency tests rely on static sets of stimulus items and so cannot be administered validly to the same individual multiple times. To create a proficiency test, a large number of items of "known" difficulty must be assembled. Multiple tests of equal difficulty can be constructed then using subsets of items. We introduce the Triad Identity Matching (TIM) test and evaluate it using item response theory (IRT). Participants view face-image "triads" (N = 225) (two images of one identity, one image of a different identity) and select the different identity. In Experiment 3, university students (N = 197) showed wide-ranging accuracy on the TIM test, and IRT modeling demonstrated that the TIM items span various difficulty levels. In Experiment 3, we used IRT-based item metrics to partition the test into subsets of specific difficulties. Simulations showed that subsets of the TIM items yielded reliable estimates of subject ability. In Experiments 3a and b, we found that the student-derived IRT model reliably evaluated the ability of non-student participants and that ability generalized across different test sessions. In Experiment 3c, we show that TIM test performance correlates with other common face-recognition tests. In summary, the TIM test provides a starting point for developing a framework that is flexible and calibrated to measure proficiency across various ability levels (e.g., professionals or populations with face-processing deficits).


Asunto(s)
Reconocimiento Facial , Humanos , Reconocimiento Facial/fisiología , Estudiantes
2.
Opt Express ; 31(17): 28101-28111, 2023 Aug 14.
Artículo en Inglés | MEDLINE | ID: mdl-37710872

RESUMEN

We report on the successful amplification of 10 ns pulses to 10 J energy at 10 Hz in a DiPOLE laser amplifier using crystalline Yb:YAG/Cr:YAG composite slabs manufactured using adhesive-free bonding (AFB) technology. We demonstrate that bonded slabs are suitable for operation in high energy cryogenic laser amplifiers. We also report on frequency doubling of the beam amplified in the bonded slabs. When the pulse energy of the output infrared beam is set to 5 J, a pulse energy of 3.9 J is achieved in the green (corresponding to 78% conversion efficiency). Results demonstrate that AFB technology is suitable for producing large-sized gain material slabs and can overcome current limitations in the manufacture of large-aperture gain material pieces. We believe this work will facilitate energy scaling of high energy lasers where aperture scaling of optical elements is not achievable via conventional manufacturing techniques.

3.
Eur J Public Health ; 33(1): 49-55, 2023 02 03.
Artículo en Inglés | MEDLINE | ID: mdl-36453890

RESUMEN

BACKGROUND: Within the current context of continued austerity and post-pandemic recovery, it remains important that Local Government services address the increasing needs of residents as cost-effectively as possible. Alliancing, whereby services work collaboratively focusing on the 'whole-system', has gained popularity as a tool with the potential to support collaborative whole systems approaches. This synthesis aims to identify how alliancing can be successfully operationalised in the commissioning of public health, wider National Health Service (NHS) and social care-related services. METHODS: A realist literature synthesis was undertaken in order to identify underlying generative mechanisms associated with alliancing, the contextual conditions surrounding the implementation and operationalisation of the alliancing approach mechanisms, and the outcomes produced as a result. An iterative approach was taken, using a recent systematic review of the effectiveness of Alliancing, online database searches, and grey literature searches. RESULTS: Three mechanistic components were identified within the data as being core to the successful implementation of alliances in public health and social care-related services within Local Government: (i) Achieving a system-level approach; (ii) placing local populations at the heart of the system; and (iii) creating a cultural shift. Programme theories were postulated within these components. CONCLUSIONS: The alliancing approach offers an opportunity to achieve system-level change with the potential to benefit local populations. The realist synthesis approach taken within this study has provided insights into the necessary contextual and mechanistic factors of the Alliancing approach, above and beyond effectiveness outcomes typically collected through more conventional evaluation methodologies.


Asunto(s)
Salud Pública , Medicina Estatal , Humanos , Gobierno Local , Proyectos de Investigación , Grupos de Población
4.
BMC Infect Dis ; 22(1): 920, 2022 Dec 09.
Artículo en Inglés | MEDLINE | ID: mdl-36494644

RESUMEN

BACKGROUND: Current tuberculosis (TB) regimen development pathways are slow and in urgent need of innovation. We investigated novel phase IIc and seamless phase II/III trials utilizing multi-arm multi-stage and Bayesian response adaptive randomization trial designs to select promising combination regimens in a platform adaptive trial. METHODS: Clinical trial simulation tools were built using predictive and validated parametric survival models of time to culture conversion (intermediate endpoint) and time to TB-related unfavorable outcome (final endpoint). This integrative clinical trial simulation tool was used to explore and optimize design parameters for aforementioned trial designs. RESULTS: Both multi-arm multi-stage and Bayesian response adaptive randomization designs were able to reliably graduate desirable regimens in ≥ 95% of trial simulations and reliably stop suboptimal regimens in ≥ 90% of trial simulations. Overall, adaptive phase IIc designs reduced patient enrollment by 17% and 25% with multi-arm multi-stage and Bayesian response adaptive randomization designs respectively compared to the conventional sequential approach, while seamless designs reduced study duration by 2.6 and 3.5 years respectively (typically ≥ 8.5 years for standard sequential approach). CONCLUSIONS: In this study, we demonstrate that adaptive trial designs are suitable for TB regimen development, and we provide plausible design parameters for a platform adaptive trial. Ultimately trial design and specification of design parameters will depend on clinical trial objectives. To support decision-making for clinical trial designs in contemporary TB regimen development, we provide a flexible clinical trial simulation tool that can be used to explore and optimize design features and parameters.


Asunto(s)
Proyectos de Investigación , Tuberculosis , Humanos , Teorema de Bayes , Distribución Aleatoria , Tuberculosis/tratamiento farmacológico , Simulación por Computador
5.
Anaesthesia ; 77(3): 293-300, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-34861743

RESUMEN

Different introducers are available to assist with tracheal intubation. Subtle differences in the design of introducers can have a marked effect on safety and performance. The Difficult Airway Society's Airway Device Evaluation Project Team proposal states that devices should only be purchased for which there is at least a case-control study on patients assessing airway devices. However, resources are not currently available to carry out a case-control study on all introducers available on the market. This study comprised a laboratory and manikin-based investigation to identify introducers that could be suitable for clinical investigation. We included six different introducers in laboratory-based assessments (design characteristics) and manikin-based assessments involving the participation of 30 anaesthetists. Each anaesthetist attempted placement in the manikin's trachea with each of the six introducers in a random order. Outcomes included first-time insertion success rate; insertion success rate; number of attempts; time to placement; and distance placed. Each anaesthetist also completed a questionnaire. First-time insertion success rate depended significantly on the introducer used (p = 0.0016) and varied from 47% (Armstrong and P3) to 77% (Intersurgical and Frova). Median time to placement (including oesophageal placement) varied from 10 s (Eschmann and Frova) to 20 s (P3) (p = 0.0025). Median time to successful placement in the trachea varied from 9 s (Frova) to 22 s (Armstrong) (p = 0.037). We found that the Armstrong and P3 devices were not as acceptable as other introducers and, without significant improvements to their design and characteristics, the use of these devices in studies on patients is questionable. The study protocol is suitable for differentiating between different introducers and could be used as a basis for assessing other types of devices.


Asunto(s)
Manejo de la Vía Aérea/normas , Anestesistas/normas , Diseño de Equipo/normas , Intubación Intratraqueal/normas , Maniquíes , Encuestas y Cuestionarios , Manejo de la Vía Aérea/instrumentación , Competencia Clínica/normas , Diseño de Equipo/instrumentación , Humanos , Intubación Intratraqueal/instrumentación , Tráquea/anatomía & histología
6.
Opt Express ; 29(4): 5607-5623, 2021 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-33726095

RESUMEN

In this paper, we present a model to predict thermal stress-induced birefringence in high energy, high repetition rate diode-pumped Yb:YAG lasers. The model calculates thermal depolarisation as a function of gain medium geometry, pump power, cooling parameters, and input polarisation state. We show that model predictions are in good agreement with experimental observations carried out on a DiPOLE 100 J, 10 Hz laser amplifier. We show that single-pass depolarisation strongly depends on input polarisation state and pumping parameters. In the absence of any depolarisation compensation scheme, depolarisation varies over a range between 5% and 40%. The strong dependence of thermal stress-induced depolarisation on input polarisation indicates that, in the case of multipass amplifiers, the use of waveplates after every pass can reduce depolarisation losses significantly. We expect that this study will assist in the design and optimisation of Yb:YAG lasers.

7.
Proc Natl Acad Sci U S A ; 115(24): 6171-6176, 2018 06 12.
Artículo en Inglés | MEDLINE | ID: mdl-29844174

RESUMEN

Achieving the upper limits of face identification accuracy in forensic applications can minimize errors that have profound social and personal consequences. Although forensic examiners identify faces in these applications, systematic tests of their accuracy are rare. How can we achieve the most accurate face identification: using people and/or machines working alone or in collaboration? In a comprehensive comparison of face identification by humans and computers, we found that forensic facial examiners, facial reviewers, and superrecognizers were more accurate than fingerprint examiners and students on a challenging face identification test. Individual performance on the test varied widely. On the same test, four deep convolutional neural networks (DCNNs), developed between 2015 and 2017, identified faces within the range of human accuracy. Accuracy of the algorithms increased steadily over time, with the most recent DCNN scoring above the median of the forensic facial examiners. Using crowd-sourcing methods, we fused the judgments of multiple forensic facial examiners by averaging their rating-based identity judgments. Accuracy was substantially better for fused judgments than for individuals working alone. Fusion also served to stabilize performance, boosting the scores of lower-performing individuals and decreasing variability. Single forensic facial examiners fused with the best algorithm were more accurate than the combination of two examiners. Therefore, collaboration among humans and between humans and machines offers tangible benefits to face identification accuracy in important applications. These results offer an evidence-based roadmap for achieving the most accurate face identification possible.


Asunto(s)
Algoritmos , Identificación Biométrica/métodos , Cara/anatomía & histología , Ciencias Forenses/métodos , Humanos , Aprendizaje Automático , Reproducibilidad de los Resultados
8.
BMC Med ; 18(1): 314, 2020 11 04.
Artículo en Inglés | MEDLINE | ID: mdl-33143704

RESUMEN

BACKGROUND: The STREAM trial demonstrated that a 9-11-month "short" regimen had non-inferior efficacy and comparable safety to a 20+ month "long" regimen for the treatment of rifampicin-resistant tuberculosis. Imbalance in the components of the composite primary outcome merited further investigation. METHODS: Firstly, the STREAM primary outcomes were mapped to alternatives in current use, including WHO programmatic outcome definitions and other recently proposed modifications for programmatic or research purposes. Secondly, the outcomes were re-classified according to the likelihood that it was a Failure or Relapse (FoR) event on a 5-point Likert scale: Definite, Probable, Possible, Unlikely, and Highly Unlikely. Sensitivity analyses were employed to explore the impact of informative censoring. The protocol-defined modified intention-to-treat (MITT) analysis population was used for all analyses. RESULTS: Cure on the short regimen ranged from 75.1 to 84.2% across five alternative outcomes. However, between-regimens results did not exceed 1.3% in favor of the long regimen (95% CI upper bound 10.1%), similar to the primary efficacy results from the trial. Considering only Definite or Probable FoR events, there was weak evidence of a higher risk of FoR in the short regimen, HR 2.19 (95%CI 0.90, 5.35), p = 0.076; considering only Definite FoR events, the evidence was stronger, HR 3.53 (95%CI 1.05, 11.87), p = 0.030. Cumulative number of grade 3-4 AEs was the strongest predictor of censoring. Considering a larger effect of informative censoring attenuated treatment differences, although 95% CI were very wide. CONCLUSION: Five alternative outcome definitions gave similar overall results. The risk of failure or relapse (FoR) may be higher in the short regimen than in the long regimen, highlighting the importance of how loss to follow-up and other censoring is accounted for in analyses. The outcome of time to FoR should be considered as a primary outcome for future drug-sensitive and drug-resistant TB treatment trials, provided sensitivity analyses exploring the impact of departures from independent censoring are also included.


Asunto(s)
Antituberculosos/uso terapéutico , Rifampin/uso terapéutico , Tuberculosis Resistente a Múltiples Medicamentos/tratamiento farmacológico , Antituberculosos/farmacología , Humanos , Rifampin/farmacología , Resultado del Tratamiento
9.
Opt Express ; 28(3): 3636-3646, 2020 Feb 03.
Artículo en Inglés | MEDLINE | ID: mdl-32122028

RESUMEN

We compare for the first time the influence of different Yb:YAG gain media on the performance of a large-area, high average-power laser system with an output energy of up to 6 J. Monocrystalline slabs grown by a new technique without central growth defect are compared with ceramics. Small signal gain, maximum output energy and thermal lensing are compared for ceramic slabs with co-sintered amplified spontaneous emission (ASE) absorber cladding, monocrystalline slab with and without optically bonded ASE absorber cladding, and surface structured monocrystalline slabs. We show that these large monocrystals with optically bonded absorber cladding have similar performance to cladded ceramics, so far the only material for high-energy Yb:YAG lasers.

10.
Br J Surg ; 107(8): 1004-1012, 2020 07.
Artículo en Inglés | MEDLINE | ID: mdl-32250452

RESUMEN

BACKGROUND: This paper describes the development and validation of an electronic personal assessment questionnaire for vascular conditions (ePAQ-VAS) that captures the symptomatology, quality of life and clinically relevant data of patients presenting to vascular services. METHODS: A two-stage survey was conducted in patients attending a tertiary vascular department. Patients completed the ePAQ-VAS remotely online, or on site using an electronic tablet. In the first stage of the survey, the responses were used to perform confirmatory factor analysis to assess the construct validity and remove redundant items. The internal reliability of disease-specific scales was investigated. In the second stage of the survey, the acceptability, known-group validity, test-retest reliability, and responsiveness of ePAQ-VAS was assessed. RESULTS: In total, 721 patients completed ePAQ-VAS. Their mean(s.d.) age was 63·5(15·7) years and 468 (64·9 per cent) were men. Some 553 patients (76·7 per cent) completed the questionnaire in clinic and the remainder completed the questionnaire online. The results of the confirmatory factor analysis confirmed the conceptual model for ePAQ-VAS structure and eliminated six items. Internal reliability was acceptable for all the scales (Cronbach's α greater than 0·7). The test-retest reliability measured by the intraclass correlation coefficient ranged from 0·65 to 0·99. The results showed that the instrument was responsive over time with the standardized response mean ranging from 0·69 to 1·60. CONCLUSION: ePAQ-VAS is a holistic data-collection process that is relevant to vascular service users and has potential to contribute to patient-focused care and the collection of aggregate data for service evaluation. A demonstration version of the final version of ePAQ can be viewed at http://demo-questionnaire.epaq.co.uk/home/project?id=VASC_1.7&page=1.


ANTECEDENTES: Este artículo describe el desarrollo y la validación de un cuestionario electrónico de evaluación personal para enfermedades vasculares (ePAQ-VAS) que incluye la sintomatología, la calidad de vida y los datos clínicamente relevantes para los pacientes que son atendidos en los servicios de patología vascular. MÉTODOS: Se llevó a cabo una encuesta en dos fases entre los pacientes atendidos en un servicio de patología vascular de tercer nivel. Los pacientes completaron el cuestionario ePAQ-VAS a distancia en línea o bien en el centro hospitalario mediante una tableta electrónica. En la primera fase de la encuesta, las respuestas se utilizaron para realizar un análisis factorial de confirmación para evaluar la validez del diseño y eliminar los elementos redundantes. Se investigó la fiabilidad interna de las escalas específicas de la enfermedad. En la segunda fase de la encuesta, se evaluó la aceptabilidad, la validez de grupo conocida, la fiabilidad test-retest y la capacidad de respuesta del ePAQ-VAS. RESULTADOS: En total, 721 pacientes completaron el ePAQ-VAS, la edad media fue de 63,5 años (DE 15,7); el 64,9% eran varones (468); el 76% de los pacientes (553) completaron el cuestionario en la clínica y los pacientes restantes lo hicieron electrónicamente a distancia. Los resultados del análisis factorial de confirmación confirmaron el modelo conceptual para la estructura ePAQ-VAS y eliminaron seis ítems. La fiabilidad interna fue aceptable para todas las escalas (alfa de Cronbach > 0,7). La fiabilidad test-retest medida por el coeficiente de correlación intraclase osciló entre 0,65-0,99. Los resultados mostraron que el instrumento responde con el tiempo con una media de respuesta estandarizada que varía de 0,69 a 1,60. CONCLUSIÓN: El ePAQ-VAS es un proceso holístico de recopilación de datos que es relevante para los usuarios de servicios de patología vascular y tiene el potencial de contribuir a la atención centrada en el paciente y a la recopilación de datos agregados para la evaluación del servicio.


Asunto(s)
Encuestas y Cuestionarios , Enfermedades Vasculares/diagnóstico , Adulto , Anciano , Análisis Factorial , Femenino , Humanos , Masculino , Persona de Mediana Edad , Calidad de Vida , Reproducibilidad de los Resultados
11.
J Appl Microbiol ; 128(4): 1025-1037, 2020 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-31793161

RESUMEN

AIMS: This study aimed to identify the most effective antimicrobial agent from a selection of essential oils (EO) and investigate its bactericidal properties against Pseudomonas aeruginosa. METHODS AND RESULTS: The disc diffusion assay and minimal inhibitory/bactericidal concentration tests were used to identify antimicrobial potential. Several oils exhibited antimicrobial effects at concentrations as low as 0·03% (v/v). Significantly, cinnamon (Cinnamomum zeylanicum) bark EO exhibited a broad-spectrum activity against Gram-negative and Gram-positive bacteria and showed bacteriostatic and bactericidal effects against P. aeruginosa PAO1 at 0·125% (v/v) and all other tested organisms, including known multidrug resistant species. Time-kill assays and metabolic activity tests showed cinnamon oil to exhibit rapid killing, with bactericidal activity observed in ≤6 min at ≥0·5% (v/v). Furthermore, scanning electron microscopy and a membrane permeability assay indicated damage to membrane integrity, loss of turgor and cell collapse. CONCLUSION: Cinnamon bark EO is a broad-spectrum antimicrobial agent capable of rapid killing at low concentrations. SIGNIFICANCE AND IMPACT OF THE STUDY: This study provides a sound basis for further investigation of the potential of cinnamon bark EO as an alternative to conventional antimicrobial products due to its fast-acting bactericidal properties at low concentrations.


Asunto(s)
Antibacterianos/farmacología , Cinnamomum zeylanicum/química , Aceites Volátiles/farmacología , Aceites de Plantas/farmacología , Pseudomonas aeruginosa/efectos de los fármacos , Bacterias/clasificación , Bacterias/efectos de los fármacos , Membrana Celular/efectos de los fármacos , Pruebas de Sensibilidad Microbiana
12.
Acta Oncol ; 58(12): 1752-1756, 2019 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-31512931

RESUMEN

Background: Radiation therapy (RT) plays an important role in management of pediatric central nervous system (CNS) malignancies. Centers are increasingly utilizing pencil beam scanning proton therapy (PBS-PT). However, the risk of brainstem necrosis has not yet been reported. In this study, we evaluate the rate of brainstem necrosis in pediatric patients with CNS malignancies treated with PBS-PT.Material and methods: Pediatric patients with non-hematologic CNS malignancies treated with PBS-PT who received dose to the brainstem were included. All procedures were approved by the institutional review board. Brainstem necrosis was defined as symptomatic toxicity. The actuarial rate was analyzed by the Kaplan Meier method.Results: One hundred and sixty-six consecutive patients were reviewed. Median age was 10 years (range 0.5-21 years). Four patients (2.4%) had prior radiation. Median maximum brainstem dose in the treated course was 55.4 Gy[RBE] (range 0.15-61.4 Gy[RBE]). In patients with prior RT, cumulative median maximum brainstem dose was 98.0 Gy [RBE] (range 17.0-111.0 Gy [RBE]). Median follow up was 19.6 months (range, 2.0-63.0). One patient who had previously been treated with twice-daily radiation therapy and intrathecal (IT) methotrexate experienced brainstem necrosis. The actuarial incidence of brainstem necrosis was 0.7% at 24 months (95% CI 0.1-5.1%).Conclusion: The rate of symptomatic brainstem necrosis was extremely low after treatment with PBS-PT in this study. Further work to clarify clinical and dosimetric parameters associated with risk of brainstem necrosis after PBS-PT is needed.


Asunto(s)
Tronco Encefálico/efectos de la radiación , Neoplasias del Sistema Nervioso Central/radioterapia , Terapia de Protones/efectos adversos , Adolescente , Astrocitoma/radioterapia , Tronco Encefálico/patología , Niño , Preescolar , Ependimoma/radioterapia , Femenino , Humanos , Lactante , Estimación de Kaplan-Meier , Masculino , Meduloblastoma/radioterapia , Necrosis/epidemiología , Necrosis/etiología , Terapia de Protones/métodos , Dosis de Radiación , Traumatismos por Radiación/complicaciones , Reirradiación/efectos adversos , Adulto Joven
13.
Anaesthesia ; 74(5): 619-629, 2019 May.
Artículo en Inglés | MEDLINE | ID: mdl-30793289

RESUMEN

To avoid potentially fatal wrong-route neuraxial drug errors, international standard ISO 80369-6 specifying a non-Luer neuraxial connector design was published in 2016. We describe usability studies used in development of the design. Thirty-eight doctors and 17 nurses performed simulated procedures on manikins, using devices fitted with Luer connectors or draft ISO 80369-6 'non-Luer' connectors. The procedures included spinal anaesthesia; intrathecal chemotherapy; lumbar puncture, cerebrospinal fluid collection and pressure measurement; epidural catheter placement with bolus injection and critical care use. Participants attempted cross connection between neuraxial connectors and a range of other medical device connectors, including those from the ISO 80369 small-bore connector series. Video recording analysis was used for all assessments. Participants subjectively assessed performance of the draft non-Luer connector, including suitability for routine clinical use. Participants performed 198 procedures. The connector achieved easy, leak-free connections. The willingness of participants to use the non-Luer connectors were: spinal anaesthesia 100%; intrathecal chemotherapy 88%; lumbar puncture, cerebrospinal fluid collection and pressure measurement 93%; epidural catheter placement with bolus injection 78%; critical care use 100%. Concerns raised were generally device related, rather than connector related. Most cross-connection attempts failed, even using above clinical forces and, when successful, were judged of low clinical risk potential; the exception was a malaligned connection between the non-Luer slip and female Luer connectors. This led to revision of the dimensional tolerances of the non-Luer connector to reduce this risk, before publication of the final specification in 2016. We conclude that the ISO 80369-6 neuraxial non-Luer connector is suitable for clinical use.


Asunto(s)
Anestesia Raquidea/instrumentación , Errores de Medicación/prevención & control , Antineoplásicos/administración & dosificación , Competencia Clínica , Diseño de Equipo , Seguridad de Equipos , Humanos , Inyecciones Epidurales/instrumentación , Inyecciones Espinales/instrumentación , Maniquíes , Seguridad del Paciente , Punción Espinal/instrumentación
14.
BMC Med ; 16(1): 73, 2018 05 21.
Artículo en Inglés | MEDLINE | ID: mdl-29779492

RESUMEN

BACKGROUND: Chest radiographs are used for diagnosis and severity assessment in tuberculosis (TB). The extent of disease as determined by smear grade and cavitation as a binary measure can predict 2-month smear results, but little has been done to determine whether radiological severity reflects the bacterial burden at diagnosis. METHODS: Pre-treatment chest x-rays from 1837 participants with smear-positive pulmonary TB enrolled into the REMoxTB trial (Gillespie et al., N Engl J Med 371:1577-87, 2014) were retrospectively reviewed. Two clinicians blinded to clinical details using the Ralph scoring system performed separate readings. An independent reader reviewed discrepant results for quality assessment and cavity presence. Cavitation presence was plotted against time to positivity (TTP) of sputum liquid cultures (MGIT 960). The Wilcoxon rank sum test was performed to calculate the difference in average TTP for these groups. The average lung field affected was compared to log 10 TTP by linear regression. Baseline markers of disease severity and patient characteristics were added in univariable regression analysis against radiological severity and a multivariable regression model was created to explore their relationship. RESULTS: For 1354 participants, the median TTP was 117 h (4.88 days), being 26 h longer (95% CI 16-30, p < 0.001) in patients without cavitation compared to those with cavitation. The median percentage of lung-field affected was 18.1% (IQR 11.3-28.8%). For every 10-fold increase in TTP, the area of lung field affected decreased by 11.4%. Multivariable models showed that serum albumin decreased significantly as the percentage of lung field area increased in both those with and without cavitation. In addition, BMI and logged TTP had a small but significant effect in those with cavitation and the number of severe TB symptoms in the non-cavitation group also had a small effect, whilst other factors found to be significant on univariable analysis lost this effect in the model. CONCLUSIONS: The radiological severity of disease on chest x-ray prior to treatment in smear positive pulmonary TB patients is weakly associated with the bacterial burden. When compared against other variables at diagnosis, this effect is lost in those without cavitation. Radiological severity does reflect the overall disease severity in smear positive pulmonary TB, but we suggest that clinicians should be cautious in over-interpreting the significance of radiological disease extent at diagnosis.


Asunto(s)
Pared Torácica/diagnóstico por imagen , Tuberculosis Pulmonar/diagnóstico por imagen , Rayos X/efectos adversos , Adulto , Femenino , Humanos , Masculino , Tuberculosis Pulmonar/diagnóstico , Adulto Joven
15.
Am J Physiol Lung Cell Mol Physiol ; 312(1): L100-L109, 2017 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-27836902

RESUMEN

The prevalence of a sedentary (SED) life style combined with calorically rich diets has spurred the rise in childhood obesity, which, in turn, translates to adverse health effects in adulthood. Obesity and lack of active (ACT) lifestyle may increase susceptibility to air pollutants. We housed 22-day-old female Long-Evans rats in a cage without (SED) or with a running wheel (ACT). After 10 wk the rats ran 310 ± 16.3 km. Responses of SED and ACT rats to whole-body O3 (0, 0.25, 0.5, or 1.0 ppm; 5 h/day for 2 days) was assessed. Glucose tolerance testing (GTT) was performed following the first day of O3 ACT rats had less body fat and an improved glucose GTT. Ventilatory function (plethysmography) of SED and ACT groups was similarly impaired by O3 Bronchoalveolar lavage fluid (BALF) was collected after the second O3 exposure. SED and ACT rats were hyperglycemic following 1.0 ppm O3 GTT was impaired by O3 in both groups; however, ACT rats exhibited improved recovery to 0.25 and 1.0 ppm O3 BALF cell neutrophils and total cells were similarly increased in ACT and SED groups exposed to 1.0 ppm O3 O3-induced increase in eosinophils was exacerbated in SED rats. Chronic exercise from postweaning to adulthood improved some of the metabolic and pulmonary responses to O3 (GTT and eosinophils) but several other parameters were unaffected. The reduction in O3-induced rise in BALF eosinophils in ACT rats suggests a possible link between a SED lifestyle and incidence of asthma-related symptoms from O3.


Asunto(s)
Envejecimiento/fisiología , Ozono/farmacología , Condicionamiento Físico Animal , Destete , Animales , Biomarcadores/sangre , Composición Corporal/efectos de los fármacos , Líquido del Lavado Bronquioalveolar/citología , Recuento de Células , Susceptibilidad a Enfermedades , Femenino , Pletismografía , Ratas Long-Evans , Factores de Tiempo
16.
Artículo en Inglés | MEDLINE | ID: mdl-28827417

RESUMEN

In a multiple-dose-ranging trial, we previously evaluated higher doses of rifampin in patients for 2 weeks. The objectives of the current study were to administer higher doses of rifampin for a longer period to compare the pharmacokinetics, safety/tolerability, and bacteriological activity of such regimens. In a double-blind, randomized, placebo-controlled, phase II clinical trial, 150 Tanzanian patients with tuberculosis (TB) were randomized to receive either 600 mg (approximately 10 mg/kg of body weight), 900 mg, or 1,200 mg rifampin combined with standard doses of isoniazid, pyrazinamide, and ethambutol administered daily for 2 months. Intensive pharmacokinetic sampling occurred in 63 patients after 6 weeks of treatment, and safety/tolerability was assessed. The bacteriological response was assessed by culture conversion in liquid and solid media. Geometric mean total exposures (area under the concentration-versus-time curve up to 24 h after the dose) were 24.6, 50.8, and 76.1 mg · h/liter in the 600-mg, 900-mg, and 1,200-mg groups, respectively, reflecting a nonlinear increase in exposure with the dose (P < 0.001). Grade 3 adverse events occurred in only 2 patients in the 600-mg arm, 4 patients in the 900-mg arm, and 5 patients in the 1,200-mg arm. No significant differences in the bacteriological response were observed. Higher daily doses of rifampin (900 and 1,200 mg) resulted in a more than proportional increase in rifampin exposure in plasma and were safe and well tolerated when combined with other first-line anti-TB drugs for 2 months, but they did not result in improved bacteriological responses in patients with pulmonary TB. These findings have warranted evaluation of even higher doses of rifampin in follow-up trials. (This study has been registered at ClinicalTrials.gov under identifier NCT00760149.).


Asunto(s)
Antibióticos Antituberculosos/administración & dosificación , Antibióticos Antituberculosos/farmacocinética , Rifampin/administración & dosificación , Rifampin/farmacocinética , Tuberculosis Pulmonar/tratamiento farmacológico , Adulto , Antibióticos Antituberculosos/efectos adversos , Relación Dosis-Respuesta a Droga , Método Doble Ciego , Quimioterapia Combinada , Etambutol/uso terapéutico , Femenino , Humanos , Isoniazida/uso terapéutico , Masculino , Mycobacterium tuberculosis/efectos de los fármacos , Pirazinamida/uso terapéutico , Rifampin/efectos adversos , Resultado del Tratamiento , Tuberculosis Pulmonar/mortalidad
17.
Br J Surg ; 104(11): 1424-1432, 2017 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-28771700

RESUMEN

BACKGROUND: Varicose veins can affect quality of life. Patient-reported outcome measures (PROMs) provide a direct report from the patient about the impact of the disease without interpretation from clinicians or anyone else. The aim of this study was to examine the quality of the psychometric evidence for PROMs used in patients with varicose veins. METHODS: A systematic review was undertaken to identify studies that reported the psychometric properties of generic and disease-specific PROMs in patients with varicose veins. Literature searches were conducted in databases including MEDLINE, up to July 2016. The psychometric criteria used to assess these studies were adapted from published recommendations in accordance with US Food and Drug Administration guidance. RESULTS: Nine studies were included which reported on aspects of the development and/or validation of one generic (36-Item Short Form Health Survey, SF-36®) and three disease-specific (Aberdeen Varicose Vein Questionnaire, AVVQ; Varicose Veins Symptoms Questionnaire, VVSymQ®; Specific Quality-of-life and Outcome Response - Venous, SQOR-V) PROMs. The evidence from included studies provided data to support the construct validity, test-retest reliability and responsiveness of the AVVQ. However, its content validity, including weighting of the AVVQ questions, was biased and based on the opinion of clinicians, and the instrument had poor acceptability. VVSymQ® displayed good responsiveness and acceptability rates. SF-36® was considered to have satisfactory responsiveness and internal consistency. CONCLUSION: There is a scarcity of psychometric evidence for PROMs used in patients with varicose veins. These data suggest that AVVQ and SF-36® are the most rigorously evaluated PROMs in patients with varicose veins.


Asunto(s)
Medición de Resultados Informados por el Paciente , Várices/cirugía , Humanos , Psicometría , Encuestas y Cuestionarios
18.
Br J Surg ; 104(10): 1273-1283, 2017 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-28632941

RESUMEN

BACKGROUND: Hospitals that conduct more procedures on the carotid arteries may achieve better outcomes. In the context of ongoing reconfiguration of UK vascular services, this systematic review was conducted to evaluate the relationship between the volume of carotid procedures and outcomes, including mortality and stroke. METHODS: Searches of electronic databases identified studies that reported the effect of hospital or clinician volume on outcomes. Reference and citation searches were also performed. Inclusion was restricted to European populations on the basis that the model of healthcare delivery is similar across Europe, but differs from that in the USA and elsewhere. Analyses of hospital and clinician volume, and carotid endarterectomy (CEA) and carotid artery stenting (CAS) were conducted separately. RESULTS: Eleven eligible studies were identified (233 411 participants), five from the UK, two from Sweden, one each from Germany, Finland and Italy, and a combined German, Austrian and Swiss population. All studies were observational. Two large studies (179 736 patients) suggested an inverse relationship between hospital volume and mortality (number needed to treat (NNT) as low as 165), and combined mortality and stroke (NNT as low as 93), following CEA. The evidence was less clear for CAS; multiple analyses in three studies did not identify convincing evidence of an association. Limited data are available on the relationship between clinician volume and outcome in CAS; in CEA, an inverse relationship was identified by two of three small studies. CONCLUSION: The evidence from the largest and highest-quality studies included in this review support the centralization of CEA.


Asunto(s)
Enfermedades de las Arterias Carótidas/cirugía , Endarterectomía Carotidea/estadística & datos numéricos , Hospitales de Alto Volumen/estadística & datos numéricos , Stents/estadística & datos numéricos , Endarterectomía Carotidea/efectos adversos , Endarterectomía Carotidea/mortalidad , Europa (Continente) , Mortalidad Hospitalaria , Humanos , Tiempo de Internación , Evaluación de Resultado en la Atención de Salud , Complicaciones Posoperatorias , Factores de Riesgo , Stents/efectos adversos , Accidente Cerebrovascular/etiología , Accidente Cerebrovascular/mortalidad
19.
Eur J Vasc Endovasc Surg ; 53(1): 77-88, 2017 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-27856168

RESUMEN

OBJECTIVE: To evaluate the relationship between the volume of abdominal aortic aneurysm (AAA) procedures undertaken and the primary outcome of mortality in Europe. Previous systematic reviews of this relationship are outdated and are overwhelmingly based on US data. DATA SOURCES: Comprehensive searching within MEDLINE and other bibliographic databases supplemented by citation searching and hand-searching of journals was undertaken to identify studies that reported the effect of hospital or clinician volume on any reported outcomes in adult, European populations, undergoing AAA repair and published in the last 10 years. METHODS: Two reviewers conducted study selection with independent, duplicate data extraction and quality assessment. A planned meta-analysis was not conducted because of the high risk of bias, the likelihood of individual study subjects being included in more than one study and diversity in the clinical populations studied and methods used. RESULTS: Sixteen studies (n = 237,074 participants) from the UK (n = 11 studies), Germany (n = 3 studies), Norway (n = 1 study), and one from the UK and Sweden were included. Data in the included studies came from administrative databases and clinical registries incorporating a variety of clinical and procedural groups; the study quality was limited by the use of observational study designs. Overall, the evidence favoured the existence of an inverse volume outcome relationship between hospital volume and mortality. Insufficient evidence was available to reach conclusions on the relationship between clinician volume and outcome and between hospital or clinician volume and secondary outcomes including complications and length of hospital stay. CONCLUSIONS: The evidence from this review suggests a relationship between the hospital volume of AAA procedures conducted and short-term mortality; however, as volume typically represents a complex amalgamation of factors further research will be useful to identify the core characteristics of volume that influence improved outcomes.


Asunto(s)
Aneurisma de la Aorta Abdominal/mortalidad , Aneurisma de la Aorta Abdominal/cirugía , Hospitales/estadística & datos numéricos , Complicaciones Posoperatorias/mortalidad , Procedimientos Quirúrgicos Vasculares/estadística & datos numéricos , Rotura de la Aorta/mortalidad , Rotura de la Aorta/cirugía , Urgencias Médicas , Europa (Continente) , Humanos , Tiempo de Internación , Procedimientos Quirúrgicos Vasculares/efectos adversos
20.
BMC Infect Dis ; 17(1): 571, 2017 08 15.
Artículo en Inglés | MEDLINE | ID: mdl-28810911

RESUMEN

BACKGROUND: The implementation of rapid drug susceptibility testing (DST) is a current global priority for TB control. However, data are scarce on patient-relevant outcomes for presumptive diagnosis of drug-resistant tuberculosis (pDR-TB) evaluated under field conditions in high burden countries. METHODS: Observational study of pDR-TB patients referred by primary and secondary health units. TB reference centers addressing DR-TB in five cities in Brazil. Patients age 18 years and older were eligible if pDR-TB, culture positive results for Mycobacterium tuberculosis and, if no prior DST results from another laboratory were used by a physician to start anti-TB treatment. The outcome measures were median time from triage to initiating appropriate anti-TB treatment, empirical treatment and, the treatment outcomes. RESULTS: Between February,16th, 2011 and February, 15th, 2012, among 175 pDR TB cases, 110 (63.0%) confirmed TB cases with DST results were enrolled. Among study participants, 72 (65.5%) were male and 62 (56.4%) aged 26 to 45 years. At triage, empirical treatment was given to 106 (96.0%) subjects. Among those, 85 were treated with first line drugs and 21 with second line. Median time for DST results was 69.5 [interquartile - IQR: 35.7-111.0] days and, for initiating appropriate anti-TB treatment, the median time was 1.0 (IQR: 0-41.2) days. Among 95 patients that were followed-up during the first 6 month period, 24 (25.3%; IC: 17.5%-34.9%) changed or initiated the treatment after DST results: 16/29 MDRTB, 5/21 DR-TB and 3/45 DS-TB cases. Comparing the treatment outcome to DS-TB cases, MDRTB had higher proportions changing or initiating treatment after DST results (p = 0.01) and favorable outcomes (p = 0.07). CONCLUSIONS: This study shows a high rate of empirical treatment and long delay for DST results. Strategies to speed up the detection and early treatment of drug resistant TB should be prioritized.


Asunto(s)
Antituberculosos/uso terapéutico , Mycobacterium tuberculosis/efectos de los fármacos , Tuberculosis/tratamiento farmacológico , Adulto , Anciano , Brasil , Farmacorresistencia Bacteriana , Femenino , Humanos , Masculino , Persona de Mediana Edad , Mycobacterium tuberculosis/patogenicidad , Resultado del Tratamiento , Tuberculosis/microbiología , Tuberculosis Resistente a Múltiples Medicamentos/tratamiento farmacológico , Tuberculosis Resistente a Múltiples Medicamentos/microbiología
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