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1.
Stroke ; 55(1): 31-39, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-38134265

RESUMO

BACKGROUND: Quantitative susceptibility mapping (QSM) and dynamic contrast-enhanced quantitative perfusion (DCEQP) magnetic resonance imaging sequences assessing iron deposition and vascular permeability were previously correlated with new hemorrhage in cerebral cavernous malformations. We assessed their prospective changes in a multisite trial-readiness project. METHODS: Patients with cavernous malformation and symptomatic hemorrhage (SH) in the prior year, without prior or planned lesion resection or irradiation were enrolled. Mean QSM and DCEQP of the SH lesion were acquired at baseline and at 1- and 2-year follow-ups. Sensitivity and specificity of biomarker changes were analyzed in relation to predefined criteria for recurrent SH or asymptomatic change. Sample size calculations for hypothesized therapeutic effects were conducted. RESULTS: We logged 143 QSM and 130 DCEQP paired annual assessments. Annual QSM change was greater in cases with SH than in cases without SH (P=0.019). Annual QSM increase by ≥6% occurred in 7 of 7 cases (100%) with recurrent SH and in 7 of 10 cases (70%) with asymptomatic change during the same epoch and 3.82× more frequently than clinical events. DCEQP change had lower sensitivity for SH and asymptomatic change than QSM change and greater variance. A trial with the smallest sample size would detect a 30% difference in QSM annual change during 2 years of follow-up in 34 or 42 subjects (1 and 2 tailed, respectively); power, 0.8, α=0.05. CONCLUSIONS: Assessment of QSM change is feasible and sensitive to recurrent bleeding in cavernous malformations. Evaluation of an intervention on QSM percent change may be used as a time-averaged difference between 2 arms using a repeated measures analysis. DCEQP change is associated with lesser sensitivity and higher variability than QSM. These results are the basis of an application for certification by the US Food and Drug Administration of QSM as a biomarker of drug effect on bleeding in cavernous malformations. REGISTRATION: URL: https://www.clinicaltrials.gov; Unique identifier: NCT03652181.


Assuntos
Hemangioma Cavernoso do Sistema Nervoso Central , Hemorragia , Humanos , Estudos Prospectivos , Hemorragia/etiologia , Hemorragia/complicações , Hemangioma Cavernoso do Sistema Nervoso Central/complicações , Hemangioma Cavernoso do Sistema Nervoso Central/diagnóstico por imagem , Hemangioma Cavernoso do Sistema Nervoso Central/patologia , Biomarcadores , Imageamento por Ressonância Magnética/métodos , Hemorragia Cerebral/diagnóstico por imagem , Hemorragia Cerebral/complicações
2.
Artigo em Inglês | MEDLINE | ID: mdl-38733333

RESUMO

BACKGROUND: The classification of mental, behavioural and neurodevelopmental disorders in the World Health Organization's International Classification of Diseases 11th revision (ICD-11) includes a comprehensive set of behavioural indicators (BIs) within the neurodevelopmental disorders grouping. BIs can be used to assess the severity of disorders of intellectual development in situations in which standardised measures of intellectual functioning and adaptive behaviours are not available or feasible. This international study examines the implementation characteristics of the BIs and compares them to standardised measures for assessing the severity of intellectual impairment and adaptive behaviours in disorders of intellectual development and autism spectrum disorder (ASD). The clinical utility of the ICD-11 and the fidelity of its application in international clinical settings were also assessed. METHODS: A total of 116 children and adolescents (5-18 years old) with a suspected or established diagnosis of disorders of intellectual development were included across four sites [Italy (n = 18), Sri Lanka (n = 19) and two sites in India (n = 79)]. A principal component analysis was conducted to evaluate the application of the ICD-11 guidance for combining severity levels. RESULTS: Assessment using the BIs showed a higher proportion of individuals classified with mild severity, whereas the standardised measures indicated a higher proportion of severe ratings. Additionally, individuals with co-occurring ASD tended to have more severe impairments compared with those without ASD, as indicated by both BIs and standardised measures. Overall, the BIs were considered clinically useful, although more time and consideration were required when applying the guidelines for individuals with a co-occurring disorder of intellectual development and ASD. The principal component analysis revealed one principal component representing overall disorders of intellectual development severity levels. CONCLUSIONS: The ICD-11 BIs can be implemented as intended in international clinical settings for a broad range of presentations of individuals with neurodevelopmental disorders. Use of the BIs results in similar severity diagnoses to those made using standardised measures. The BIs are expected to improve the reliability of severity assessments in settings where appropriate standardised measures for intellectual and adaptive behaviours are not available or feasible.

3.
Nicotine Tob Res ; 24(12): 1959-1967, 2022 11 12.
Artigo em Inglês | MEDLINE | ID: mdl-35704338

RESUMO

INTRODUCTION: Regulators are considering reducing the nicotine content in cigarettes to a minimally addictive level. This could particularly benefit smokers from populations vulnerable to heavy smoking and difficulties quitting. We assessed predictors of adherence among adults from vulnerable populations assigned to use very low nicotine content cigarettes (VLNCs) in randomized clinical trials, to identify characteristics of those who require additional assistance if a nicotine reduction policy were implemented. AIMS AND METHODS: Data came from three populations of vulnerable adult smokers assigned to use VLNC cigarettes (0.4 mg/g nicotine) during 12-week randomized controlled trials (n = 286): Socioeconomically disadvantaged women of reproductive age, opioid-maintained adults, and adults with affective disorders. Logistic and linear regressions modeled predictors of adherence based on changes in cotinine at week-6 and week-12 assessments relative to baseline, and as a 90% reduction in cotinine relative to baseline (full adherence: yes/no). Predictors included satisfaction with study cigarettes, craving, nicotine dependence severity, withdrawal, population membership, baseline affective-disorder symptoms, and sociodemographic characteristics. RESULTS: Dependence severity was negatively associated with both adherence measures at week 6 (p < .01), whereas increased satisfaction with study cigarettes and age were positively associated with both measures at weeks 6 and 12 (p < .01). Opioid-maintained adults exhibited reduced adherence and were less likely to reach full adherence at week 12 compared to disadvantaged women (p = .02). CONCLUSIONS: Factors associated with VLNC adherence in vulnerable populations are similar to those in the general population of smokers. Furthermore, studies are indicated investigating nicotine supplements (e.g., e-cigarettes, NRT) to support highly dependent adults faced with using VLNCs. IMPLICATIONS: This study identified factors predicting difficulty maintaining adherence to a regimen of very low nicotine content cigarettes (VLNC) among adults from vulnerable populations. Findings suggested that factors predicting difficulty maintaining adherence (greater nicotine dependence and low satisfaction with study-provided VLNC) were common across vulnerable smokers and the general population of adults who smoke. Furthermore, research should investigate alternatives to support highly dependent adults, such as pairing VLNC with supplemental, noncombusted nicotine. Some vulnerable populations (e.g., opioid-maintained adults) may be especially in need of supplemental, noncombusted nicotine.


Assuntos
Sistemas Eletrônicos de Liberação de Nicotina , Abandono do Hábito de Fumar , Produtos do Tabaco , Tabagismo , Adulto , Humanos , Feminino , Nicotina , Cotinina , Abandono do Hábito de Fumar/psicologia , Populações Vulneráveis , Analgésicos Opioides , Fumar
4.
J Intellect Disabil Res ; 66(4): 376-391, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35170825

RESUMO

BACKGROUND: The World Health Organization (WHO) has approved the 11th Revision of the International Classification of Diseases (ICD-11). A version of the ICD-11 for Mental, Behavioural and Neurodevelopmental Disorders for use in clinical settings, called the Clinical Descriptions and Diagnostic Requirements (CDDR), has also been developed. The CDDR includes behavioural indicators (BIs) for assessing the severity of disorders of intellectual development (DID) as part of the section on neurodevelopmental disorders. Reliable and valid diagnostic assessment measures are needed to improve identification and treatment of individuals with DID. Although appropriately normed, standardised intellectual and adaptive behaviour assessments are considered the optimal assessment approach in this area, they are unavailable in many parts of the world. This field study tested the BIs internationally to assess the inter-rater reliability, concurrent validity, and clinical utility of the BIs for the assessment of DID. METHODS: This international study recruited a total of 206 children and adolescents (5-18 years old) with a suspected or established diagnosis of DID from four sites across three countries [Sri-Lanka (n = 57), Italy (n = 60) and two sites in India (n = 89)]. Two clinicians assessed each participant using the BIs with one conducting the clinical interview and the other observing. Diagnostic formulations using the BIs and clinical utility ratings were collected and entered independently after each assessment. At a follow-up appointment, standardised measures (Leiter-3, Vineland Adaptive Behaviour Scales-II) were used to assess intellectual and adaptive abilities. RESULTS: The BIs had excellent inter-rater reliability (intra-class correlations ranging from 0.91 to 0.97) and good to excellent concurrent validity (intra-class correlations ranging from 0.66 to 0.82) across sites. Compared to standardised measures, the BIs had more diagnostic overlap between intellectual and adaptive functioning. The BIs were rated as quick and easy to use and applicable across severities; clear and understandable with adequate to too much level of detail and specificity to describe DID; and useful for treatment selection, prognosis assessments, communication with other health care professionals, and education efforts. CONCLUSION: The inclusion of newly developed BIs within the CDDR for ICD-11 Neurodevelopmental Disorders must be supported by information on their reliability, validity, and clinical utility prior to their widespread adoption for international use. BIs were found to have excellent inter-rater reliability, good to excellent concurrent validity, and good clinical utility. This supports use of the BIs within the ICD-11 CDDR to assist with the accurate identification of individuals with DID, particularly in settings where specialised services are unavailable.


Assuntos
Classificação Internacional de Doenças , Transtornos do Neurodesenvolvimento , Adaptação Psicológica , Adolescente , Criança , Pré-Escolar , Humanos , Itália , Reprodutibilidade dos Testes
5.
Int J Mol Sci ; 23(18)2022 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-36142437

RESUMO

Current imaging approaches used to monitor tumor progression can lack the ability to distinguish true progression from pseudoprogression. Simultaneous metabolic 2-deoxy-2-[18F]fluoro-D-glucose ([18F]FDG) positron emission tomography (PET) and magnetic resonance imaging (MRI) offers new opportunities to overcome this challenge by refining tumor identification and monitoring therapeutic responses to cancer immunotherapy. In the current work, spatial and quantitative analysis of tumor burden were performed using simultaneous [18F]FDG-PET/MRI to monitor therapeutic responses to a novel silicified cancer cell immunotherapy in a mouse model of disseminated serous epithelial ovarian cancer. Tumor progression was validated by bioluminescence imaging of luciferase expressing tumor cells, flow cytometric analysis of immune cells in the tumor microenvironment, and histopathology. While PET demonstrated the presence of metabolically active cancer cells through [18F]FDG uptake, MRI confirmed cancer-related accumulation of ascites and tissue anatomy. This approach provides complementary information on disease status without a confounding signal from treatment-induced inflammation. This work provides a possible roadmap to facilitate accurate monitoring of therapeutic responses to cancer immunotherapies.


Assuntos
Fluordesoxiglucose F18 , Neoplasias Ovarianas , Animais , Feminino , Glucose , Humanos , Imunoterapia , Imageamento por Ressonância Magnética/métodos , Camundongos , Neoplasias Ovarianas/diagnóstico por imagem , Neoplasias Ovarianas/terapia , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Tomografia por Emissão de Pósitrons/métodos , Compostos Radiofarmacêuticos , Microambiente Tumoral
6.
Ann Surg ; 273(4): 701-708, 2021 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-33201114

RESUMO

OBJECTIVE: The aim of this study was to propose an evidence-based blueprint for training, assessment, and certification of operative performance for surgical trainees. SUMMARY BACKGROUND DATA: Operative skill is a critical aspect of surgical performance. High-quality assessment of operative skill therefore has profound implications for training, accreditation, certification, and the public trust of the profession. Current methods of operative skill assessment for surgeons rely heavily on global assessment strategies across a very broad domain of procedures. There is no mechanism to assure technical competence for individual procedures. The science and scalability of operative skill assessment has progressed significantly in recent decades, and can inform a much more meaningful strategy for competency-based assessment of operative skill than has been previously achieved. METHODS: The present article reviews the current status and science of operative skill assessment and proposes a template for competency-based assessment which could be used to update training, accreditation, and certification processes. The proposal is made in reference to general surgery but is more generally applicable to other procedural specialties. RESULTS: Streamlined, routine assessment of every procedure performed by surgical trainees is feasible and would enable a more competency-based educational paradigm. In light of the constraints imposed by both clinical volume and assessment bias, trainees should be expected to become proficient and be measured against a mastery learning standard only for the most important and highest-frequency procedures. For less frequently observed procedures, performance can be compared to a norm-referenced standard and, to provide an overall trajectory of performance, analyzed in aggregate. Key factors in implementing this approach are the number of evaluations, the number of raters, the timeliness of evaluation, and evaluation items. CONCLUSIONS: A competency-based operative skill assessment can be incorporated into surgical training, assessment, and certification. The time has come to develop a systematic approach to this issue as a means of demonstrating professional standards worthy of the public trust.


Assuntos
Certificação , Competência Clínica , Educação Baseada em Competências/métodos , Avaliação Educacional/métodos , Cirurgia Geral/educação , Internato e Residência/métodos , Procedimentos Cirúrgicos Operatórios/educação , Humanos
7.
Opt Express ; 29(22): 36461-36468, 2021 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-34809057

RESUMO

Phase modulators based upon the thermo-optic effect are used widely in silicon photonics for low speed applications such as switching and tuning. The dissipation of the heat produced to drive the device to the surrounding silicon is a concern as it can dictate how compact and tightly packed components can be without concerns over thermal crosstalk. In this paper we study through modelling and experiment, on various silicon on insulator photonic platforms, how close waveguides can be placed together without significant thermal crosstalk from adjacent devices.

8.
Phys Rev Lett ; 124(1): 013606, 2020 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-31976699

RESUMO

The authors report on nonconservative coupling in a passive silicon microring between its clockwise and counterclockwise resonance modes. The coupling coefficient is adjustable using a thermo-optic phase shifter. The resulting resonance of the supermodes due to nonconservative coupling is predicted in theory and demonstrated in experiments. This Letter paves the way for fundamental studies of on-chip lasers and quantum photonics, and their potential applications.

9.
Ann Surg ; 269(2): 377-382, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-29064891

RESUMO

OBJECTIVE: To establish the number of operative performance observations needed for reproducible assessments of operative competency. BACKGROUND: Surgical training is transitioning from a time-based to a competency-based approach, but the number of assessments needed to reliably establish operative competency remains unknown. METHODS: Using a smart phone based operative evaluation application (SIMPL), residents from 13 general surgery training programs were evaluated performing common surgical procedures. Two competency metrics were investigated separately: autonomy and overall performance. Analyses were performed for laparoscopic cholecystectomy performances alone and for all operative procedures combined. Variance component analyses determined operative performance score variance attributable to resident operative competency and measurement error. Generalizability and decision studies determined number of assessments needed to achieve desired reliability (0.80 or greater) and determine standard errors of measurement. RESULTS: For laparoscopic cholecystectomy, 23 ratings are needed to achieve reproducible autonomy ratings and 17 ratings are needed to achieve reproducible overall operative performance ratings. For the undifferentiated mix of procedures, 60 ratings are needed to achieve reproducible autonomy ratings and 40 are needed for reproducible overall operative performance ratings. CONCLUSION: The number of observations needed to achieve reproducible assessments of operative competency far exceeds current certification requirements, yet remains an important and achievable goal. Attention should also be paid to the mix of cases and raters in order to assure fair judgments about operative competency and fair comparisons of trainees.


Assuntos
Competência Clínica/estatística & dados numéricos , Cirurgia Geral/educação , Cirurgia Geral/normas , Análise e Desempenho de Tarefas , Humanos
10.
Opt Express ; 27(4): 4976-4989, 2019 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-30876105

RESUMO

We theoretically investigate a new class of silicon waveguides for achieving Stimulated Brillouin Scattering (SBS) in the mid-infrared (MIR). The waveguide consists of a rectangular core supporting a low-loss optical mode, suspended in air by a series of transverse ribs. The ribs are patterned to form a finite quasi-one-dimensional phononic crystal, with the complete stopband suppressing the transverse leakage of acoustic waves, confining them to the core of the waveguide. We derive a theoretical formalism that can be used to compute the opto-acoustic interaction in such periodic structures, and find forward intramodal-SBS gains up to 1750 m-1W-1, which compares favorably with the proposed MIR SBS designs based on buried germanium waveguides. This large gain is achieved thanks to the nearly complete suppression of acoustic radiative losses.

11.
Opt Express ; 27(5): 7365-7372, 2019 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-30876301

RESUMO

In this paper, we report the generation of an ultra-sharp asymmetric resonance spectrum through Fano-like interference. This generation is accomplished by weakly coupling a high-quality factor (Q factor) Fabry-Pérot (FP) cavity and a low-Q factor FP cavity through evanescent waves. The high-Q FP cavity is formed by Sagnac loop mirrors, whilst the low-Q one is built by partially transmitting Sagnac loop reflectors. The working principle has been analytically established and numerically modelled by using temporal coupled-mode-theory (CMT), and verified using a prototype device fabricated on the 340 nm silicon-on-insulator (SOI) platform, patterned by deep ultraviolet (DUV) lithography. Pronounced asymmetric resonances with slopes up to 0.77 dB/pm have been successfully measured, which, to the best of our knowledge, is higher than the results reported in state-of-the-art devices in on-chip integrated Si photonic studies. The established theoretical analysis method can provide excellent design guidelines for devices with Fano-like resonances. The design principle can be applied to ultra-sensitive sensing, ultra-high extinction ratio switching, and more applications.

12.
Opt Lett ; 44(4): 915-918, 2019 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-30768019

RESUMO

Experimental demonstrations of silicon-on-insulator waveguide-based free-carrier effect modulators operating at 3.8 µm are presented. PIN diodes are used to inject carriers into the waveguides, and are configured to (a) use free-carrier electroabsorption to create a variable optical attenuator with 34 dB modulation depth and (b) use free-carrier electrorefraction with the PIN diodes acting as phase shifters in a Mach-Zehnder interferometer, achieving a VπLπ of 0.052 V·mm and a DC modulation depth of 22 dB. Modulation is demonstrated at data rates up to 125 Mbit/s.

13.
J Eur Acad Dermatol Venereol ; 33(5): 886-892, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30663130

RESUMO

BACKGROUND: Despite increasing awareness of the disease, rates of undiagnosed psoriatic arthritis (PsA) are high in patients with psoriasis (PsO). The validated Psoriasis Epidemiology Screening Tool (PEST) is a five-item questionnaire developed to help identify PsA at an early stage. OBJECTIVES: To assess the risk of possible undiagnosed PsA among patients with PsO and characterize patients based on PEST scores. METHODS: This study included all patients enrolled in the Corrona PsO Registry with data on all five PEST questions. Demographics, clinical characteristics and patient-reported outcomes were compared in Corrona PsO Registry patients with PEST scores ≥3 and <3 using t-tests for continuous variables and chi-squared tests for categorical variables; scores ≥3 may indicate PsA. RESULTS: Of 1516 patients with PsO, 904 did not have dermatologist-reported PsA; 112 of these 904 patients (12.4%) scored ≥3 and were significantly older, female, less likely to be working, and had higher BMI than patients with scores <3. They also had significantly longer PsO duration, were more likely to have nail PsO and had worse health status, pain, fatigue, Dermatology Life Quality Index and activity impairment. CONCLUSIONS: Improved PsA screening is needed in patients with PsO because the validated PEST identified over one-tenth of registry patients who were not noted to have PsA as having scores ≥3, who could have had undiagnosed PsA. Appropriate, earlier care is important because these patients were more likely to have nail PsO, worse health-related quality of life and worse activity impairment.


Assuntos
Artrite Psoriásica/fisiopatologia , Psoríase/epidemiologia , Sistema de Registros , Adulto , Idoso , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Psoríase/diagnóstico , Psoríase/fisiopatologia , Reprodutibilidade dos Testes , Estados Unidos/epidemiologia
14.
J Intellect Disabil Res ; 63(5): 386-407, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30628126

RESUMO

BACKGROUND: We present the work conducted to arrive at deriving behavioural indicators that could be used to guide clinical judgement in determining the presence and severity of deficits in intellectual functioning and adaptive behaviour for the purpose of making a diagnosis of disorders of intellectual development. METHODS: An interdisciplinary expert panel provided guidance in developing behavioural indicators for intellectual functioning. A national dataset of adaptive behaviour on a sample of individuals with a diagnosis of intellectual disability was used to develop the behavioural indicators for the adaptive behaviour. The adaptive behaviour data were analysed using a cluster analysis procedure to define the different severity groupings by chronological age groups. RESULTS: We present a series of tables containing behavioural indicators across the lifespan for intellectual functioning and adaptive behaviour, including conceptual, social and practical skills. These tables of behavioural indicators have been proposed for use in the clinical version of the 11th revision of the International Classification of Diseases and Related Health Problems (ICD-11) to be published by the World Health Organization. CONCLUSIONS: The proposed behavioural indicators for disorders of ID described in the present article and to be included in the ICD-11 Clinical Descriptions and Diagnostic Guidelines are put forth to assist professionals in making an informed clinical decision regarding an individual's level of intellectual functioning and adaptive behaviour for the purpose of making a determination about the presence and severity of disorders of ID.


Assuntos
Adaptação Psicológica/fisiologia , Deficiência Intelectual/diagnóstico , Deficiência Intelectual/fisiopatologia , Classificação Internacional de Doenças/normas , Guias de Prática Clínica como Assunto , Adolescente , Adulto , Idoso , Criança , Pré-Escolar , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
15.
Eur J Neurosci ; 45(7): 922-931, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-28196306

RESUMO

Although certain drugs of abuse are known to disrupt brain glucose metabolism (BGluM), the effects of opiates on BGluM are not well characterized. Moreover, preclinical positron emission tomography (PET) studies anesthetize animals during the scan, which limits clinical applications. We investigated the effects of (i) isoflurane anesthesia and (ii) intravenous morphine self-administration (MSA) on BGluM in rats. Jugular vein cannulated adult male Sprague-Dawley rats self-administered either saline (SSA) or morphine (0.5 mg/kg/infusion, 4 h/day for 12 days). All animals were scanned twice with [18 F]-fluoro-deoxy-glucose (FDG)-PET/CT at a baseline and at 2-day withdrawal from self-administration. After the IV injection of FDG, one batch of animals (n = 14) was anesthetized with isoflurane and the other batch (n = 16) was kept awake during the FDG uptake (45 min). After FDG uptake, all animals were anesthetized in order to perform a PET/CT scan (30 min). Isoflurane anesthesia, as compared to the awake condition, reduced BGluM in the olfactory, cortex, thalamus, and basal ganglia, while increasing BGluM in the midbrain, hypothalamus, hippocampus, and cerebellum. Morphine self-administered animals exhibited withdrawal signs (piloerection and increased defecation), drug seeking, and locomotor stimulation to morphine (0.5 mg/kg) during the 2 day withdrawal. The BGluM in the striatum was increased in the MSA group as compared to the SSA group; this effect was observed only in the isoflurane anesthesia, not the awake condition. These findings suggest that the choice of the FDG uptake condition may be important in preclinical PET studies and increased BGluM in the striatum may be associated with opiate seeking in withdrawal.


Assuntos
Analgésicos Opioides/efeitos adversos , Anestésicos Inalatórios/efeitos adversos , Corpo Estriado/efeitos dos fármacos , Fluordesoxiglucose F18/farmacocinética , Isoflurano/efeitos adversos , Morfina/efeitos adversos , Compostos Radiofarmacêuticos/farmacocinética , Analgésicos Opioides/administração & dosagem , Analgésicos Opioides/farmacologia , Anestesia Intravenosa/efeitos adversos , Anestésicos Inalatórios/administração & dosagem , Anestésicos Inalatórios/farmacologia , Animais , Corpo Estriado/diagnóstico por imagem , Corpo Estriado/metabolismo , Isoflurano/farmacologia , Masculino , Morfina/administração & dosagem , Morfina/farmacologia , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Ratos , Ratos Sprague-Dawley , Síndrome de Abstinência a Substâncias/etiologia
16.
Ann Surg ; 266(4): 582-594, 2017 10.
Artigo em Inglês | MEDLINE | ID: mdl-28742711

RESUMO

OBJECTIVE: This study evaluates the current state of the General Surgery (GS) residency training model by investigating resident operative performance and autonomy. BACKGROUND: The American Board of Surgery has designated 132 procedures as being "Core" to the practice of GS. GS residents are expected to be able to safely and independently perform those procedures by the time they graduate. There is growing concern that not all residents achieve that standard. Lack of operative autonomy may play a role. METHODS: Attendings in 14 General Surgery programs were trained to use a) the 5-level System for Improving and Measuring Procedural Learning (SIMPL) Performance scale to assess resident readiness for independent practice and b) the 4-level Zwisch scale to assess the level of guidance (ie, autonomy) they provided to residents during specific procedures. Ratings were collected immediately after cases that involved a categorical GS resident. Data were analyzed using descriptive statistics and supplemented with Bayesian ordinal model-based estimation. RESULTS: A total of 444 attending surgeons rated 536 categorical residents after 10,130 procedures. Performance: from the first to the last year of training, the proportion of Performance ratings for Core procedures (n = 6931) at "Practice Ready" or above increased from 12.3% to 77.1%. The predicted probability that a typical trainee would be rated as Competent after performing an average Core procedure on an average complexity patient during the last week of residency training is 90.5% (95% CI: 85.7%-94%). This falls to 84.6% for more complex patients and to less than 80% for more difficult Core procedures. Autonomy: for all procedures, the proportion of Zwisch ratings indicating meaningful autonomy ("Passive Help" or "Supervision Only") increased from 15.1% to 65.7% from the first to the last year of training. For the Core procedures performed by residents in their final 6 months of training (cholecystectomy, inguinal/femoral hernia repair, appendectomy, ventral hernia repair, and partial colectomy), the proportion of Zwisch ratings (n = 357) indicating near-independence ("Supervision Only") was 33.3%. CONCLUSIONS: US General Surgery residents are not universally ready to independently perform Core procedures by the time they complete residency training. Progressive resident autonomy is also limited. It is unknown if the amount of autonomy residents do achieve is sufficient to ensure readiness for the entire spectrum of independent practice.


Assuntos
Competência Clínica , Cirurgia Geral/educação , Internato e Residência/normas , Autonomia Profissional , Educação Baseada em Competências , Avaliação Educacional/normas , Feedback Formativo , Cirurgia Geral/normas , Humanos , Estudos Prospectivos , Estados Unidos
17.
Opt Express ; 25(24): 29798-29811, 2017 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-29221016

RESUMO

We present the characterization of a silicon Mach-Zehnder modulator with electrical packaging and show that it exhibits a large third-order intermodulation spurious-free dynamic range (> 100 dB Hz2/3). This characteristic renders the modulator particularly suitable for the generation of high spectral efficiency discrete multi-tone signals and we experimentally demonstrate a single-channel, direct detection transmission system operating at 49.6 Gb/s, exhibiting a baseband spectral efficiency of 5 b/s/Hz. Successful transmission is demonstrated over various lengths of single mode fibre up to 40 km, without the need of any amplification or dispersion compensation.

18.
Ann Surg ; 264(6): 934-948, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26967627

RESUMO

OBJECTIVE: To provide recommended practice guidelines for assessing single operative performances and for combining results of operative performance assessments into estimates of overall operative performance ability. SUMMARY BACKGROUND DATA: Operative performance is one defining characteristic of surgeons. Assessment of operative performance is needed to provide feedback with learning benefits to surgical residents in training and to assist in making progress decisions for residents. Operative performance assessment has been a focus of investigation over the past 20 years. This review is designed to integrate findings of this research into a set of recommended operative performance practices. METHODS: Literature from surgery and from other pertinent research areas (psychology, education, business) was reviewed looking for evidence to inform practice guideline development. Guidelines were created along with a conceptual and scientific foundation for each guideline. RESULTS: Ten guidelines are provided for assessing individual operative performances and 10 are provided for combing data from individual operative performances into overall judgments of operative performance ability. CONCLUSIONS: The practice guidelines organize available information to be immediately useful to program directors, to support surgical training, and to provide a conceptual framework upon which to build as the base of pertinent knowledge expands through future research and development efforts.


Assuntos
Competência Clínica/normas , Educação de Pós-Graduação em Medicina , Avaliação Educacional/normas , Cirurgia Geral/educação , Internato e Residência , Guias de Prática Clínica como Assunto , Procedimentos Cirúrgicos Operatórios/normas , Humanos
19.
Med Teach ; 38(9): 904-10, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26805785

RESUMO

BACKGROUND: The idea of competency-based education sounds great on paper. Who wouldn't argue for a standardized set of performance-based assessments to assure competency in graduating students and residents? Even so, conceptual concerns have already been raised about this new system and there is yet no evidence to refute their veracity. AIMS: We argue that practical concerns deserve equal consideration, and present evidence strongly suggesting these concerns should be taken seriously. METHOD: Specifically, we share two historical examples that illustrate what happened in two disparate contexts (K-12 education and the Department of Defense [DOD]) when competency (or outcomes-based) assessment frameworks were implemented. We then examine how observation and assessment of clinical performance stands currently in medical schools and residencies, since these methodologies will be challenged to a greater degree by expansive lists of competencies and milestones. RESULTS/CONCLUSIONS: We conclude with suggestions as to a way forward, because clearly the assessment of competency and the ability to guarantee that graduates are ready for medical careers is of utmost importance. Hopefully the headlong rush to competencies, milestones, and core entrustable professional activities can be tempered before even more time, effort, frustration and resources are invested in an endeavor which history suggests will collapse under its own weight.


Assuntos
Competência Clínica , Avaliação Educacional , Estudantes de Medicina , Avaliação Educacional/métodos , Estados Unidos
20.
Med Educ ; 49(9): 920-7, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26296408

RESUMO

CONTEXT: This study is based on the premise that the game of 'Twenty Questions' (TQ) tests the knowledge people acquire through their lives and how well they organise and store it so that they can effectively retrieve, combine and use it to address new life challenges. Therefore, performance on TQ may predict how effectively medical school applicants will organise and store knowledge they acquire during medical training to support their work as doctors. OBJECTIVES: This study was designed to determine whether TQ game performance on medical school entrance predicts performance on a clinical performance examination near graduation. METHODS: This prospective, longitudinal, observational study involved each medical student in one class playing a game of TQ on a non-medical topic during the first week of medical school. Near graduation, these students completed a 14-case clinical performance examination. Performance on the TQ task was compared with performance on the clinical performance examination. RESULTS: The 24 students who exhibited a logical approach to the TQ task performed better on all senior clinical performance examination measures than did the 26 students who exhibited a random approach. Approach to the task was a better predictor of senior examination diagnosis justification performance than was the Medical College Admission Test (MCAT) Biological Science Test score and accounts for a substantial amount of score variation not attributable to a co-relationship with MCAT Biological Science Test performance. CONCLUSIONS: Approach to the TQ task appears to be one reasonable indicator of how students process and store knowledge acquired in their everyday lives and may be a useful predictor of how they will process the knowledge acquired during medical training. The TQ task can be fitted into one slot of a mini medical interview.


Assuntos
Teste de Admissão Acadêmica , Resolução de Problemas , Critérios de Admissão Escolar , Faculdades de Medicina , Adulto , Avaliação Educacional/métodos , Humanos , Estudos Longitudinais , Masculino , Estudantes de Medicina/psicologia
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