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2.
Opt Express ; 24(16): 17928-40, 2016 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-27505760

RESUMO

Current material identification techniques rely on estimating reflectivity or emissivity which vary with viewing angle. As off-nadir remote sensing platforms become increasingly prevalent, techniques robust to changing viewing geometries are desired. A technique leveraging polarimetric hyperspectral imaging (P-HSI), to estimate complex index of refraction, N̂(ν̃), an inherent material property, is presented. The imaginary component of N̂(ν̃) is modeled using a small number of "knot" points and interpolation at in-between frequencies ν̃. The real component is derived via the Kramers-Kronig relationship. P-HSI measurements of blackbody radiation scattered off of a smooth quartz window show that N̂(ν̃) can be retrieved to within 0.08 RMS error between 875 cm-1 ≤ ν̃ ≤ 1250 cm-1. P-HSI emission measurements of a heated smooth Pyrex beaker also enable successful N̂(ν̃) estimates, which are also invariant to object temperature.

3.
Anesthesiology ; 135(5): 925, 2021 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-34520531
6.
Psychol Assess ; 35(5): 462-468, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36931819

RESUMO

The McLean Screening Instrument for Borderline Personality Disorder (MSI-BPD) is a popular screening tool for identifying people who may have borderline personality disorder (BPD). However, because women are more frequently diagnosed with the disorder than men, it is possible that the MSI-BPD differs in its ability to identify BPD as a function of gender identity. Using item response theory (IRT), we sought to determine if components of the MSI-BPD would demonstrate differential item functioning (DIF), such that one gender identity would be more likely to endorse certain items. Twenty-two thousand thirty-five college undergraduates (14,305 women) aged 18-55 years (M = 18.77, SD = 1.75) were assessed using the MSI-BPD as part of a subject pool screening between 2008 and 2019. The MSI-BPD contains 10 items that are measured dichotomously, and the authors recommend a cut-off of 7 of 10 items endorsed to maximize sensitivity and specificity to BPD. Results suggested that a two-parameter model was the best fit to the data and that unidimensionality and local independence assumptions were met. The following items demonstrated DIF: self-harm/suicidality, affective lability, abandonment, impulsivity, and anger. At equal levels of the latent construct of BPD, women were more likely to endorse self-harm/suicidality, affective lability, and abandonment. Women were more likely to endorse impulsivity at higher levels of BPD, and men were more likely to endorse anger at lower levels of BPD. Ultimately, the effect sizes of these differences were small, however, and likely do not impact the individual's overall outcome on the measure. (PsycInfo Database Record (c) 2023 APA, all rights reserved).


Assuntos
Transtorno da Personalidade Borderline , Humanos , Masculino , Feminino , Transtorno da Personalidade Borderline/diagnóstico , Transtorno da Personalidade Borderline/psicologia , Identidade de Gênero , Reprodutibilidade dos Testes , Programas de Rastreamento , Sensibilidade e Especificidade
7.
Dev Neurosci ; 34(2-3): 129-39, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22572535

RESUMO

The human brain is dependent upon successfully maintaining ionic, energetic and redox homeostasis within exceptionally narrow margins for proper function. The ability of neurons to adapt to genetic and environmental perturbations and evoke a 'new normal' can be most fully appreciated in the context of neurological disorders in which clinical impairments do not manifest until late in life, although dysfunctional proteins are expressed early in development. We now know that proteins controlling ATP generation, mitochondrial stability, and the redox environment are associated with neurological disorders such as Parkinson's disease and amyotrophic lateral sclerosis. Generally, focus is placed on the role that early or long-term environmental stress has in altering the survival of cells targeted by genetic dysfunctions; however, the central nervous system undergoes several periods of intense stress during normal maturation. One of the most profound periods of stress occurs when 50% of neurons are removed via programmed cell death. Unfortunately, we have virtually no understanding of how these events proceed in individuals who harbor mutations that are lethal later in life. Moreover, there is a profound lack of information on circuit formation, cell fate during development and neurochemical compensation in either humans or the animals used to model neurodegenerative diseases. In this review, we consider the current knowledge of how energetic and oxidative stress signaling differs between neurons in early versus late stages of life, the influence of a new group of proteins that can integrate cell stress signals at the mitochondrial level, and the growing body of evidence that suggests early development should be considered a critical period for the genesis of chronic neurodegenerative diseases.


Assuntos
Encéfalo/crescimento & desenvolvimento , Degeneração Neural/metabolismo , Doenças Neurodegenerativas/metabolismo , Encéfalo/metabolismo , Encéfalo/fisiopatologia , Morte Celular/fisiologia , Humanos , Degeneração Neural/fisiopatologia , Doenças Neurodegenerativas/fisiopatologia , Neurônios/metabolismo , Estresse Oxidativo/fisiologia , Espécies Reativas de Oxigênio/metabolismo
10.
Personal Ment Health ; 16(3): 190-203, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-34731525

RESUMO

Chronic emptiness in borderline personality disorder (BPD) has received little empirical attention. We sought to examine basic properties of a single chronic emptiness item, including prevalence, reliability, validity, the relation of the emptiness item to other BPD criteria, and measures of personality. Undergraduates enrolled in psychology courses over 12 years' time completed the McLean Screening Instrument for Borderline Personality Disorder (MSI-BPD) (N = 22,217). Subsets of participants completed the International Personality Disorder Examination-Screening Questionnaire (IPDE-SQ) (N = 2732), The Revised NEO Personality Inventory (Anxiety, Angry Hostility, Depression, Positive Emotions [reversed], and Impulsivity facets) (N = 10,506), and the Depression Anxiety Stress Scales (DASS) (N = 1110) as validity indicators; 10.0% of respondents endorsed emptiness. Reliability indices suggested moderate levels of reliability between two emptiness items (r(2730) = 0.61, p < 0.001). Among BPD criteria, emptiness and identity disturbance correlated most strongly (r(22,215) = 0.81, p < 0.001). MSI emptiness was more correlated with depression on the NEO (r(10,504) = 0.43, p < 0.001) and DASS (r(1108) = 0.51, p < 0.001) than other facets of negative affect. Emptiness was more correlated with greater borderline pathology than any other MSI-BPD item (Sample 1, rtet = 0.87; Sample 2, rtet = 0.86). This criterion warrants further study and attention, especially related to assessment of BPD.


Assuntos
Transtorno da Personalidade Borderline , Emoções , Transtorno da Personalidade Borderline/diagnóstico , Transtorno da Personalidade Borderline/psicologia , Humanos , Inventário de Personalidade , Reprodutibilidade dos Testes , Estudantes
11.
J Comp Eff Res ; 11(4): 217-227, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35142536

RESUMO

Aortic stenosis has a high mortality rate in patients who do not receive aortic valve replacement. Previously, transcatheter aortic valve replacement (TAVR) was an intervention reserved for individuals deemed high-risk for surgery. Since that time, TAVR has increasingly been offered to lower risk patients, yet it is unclear whether TAVR will meet an acceptable cost-effectiveness threshold in this group. In this cost-effectiveness study, we employed a decision tree model with Monte Carlo probability sensitivity analysis to determine the incremental cost (in US$) per quality-adjusted life year (QALY) and life year (LY) of performing the TAVR procedure using the resource-intensive approach versus the minimally invasive strategy in high-risk surgical patients.


Assuntos
Estenose da Valva Aórtica , Procedimentos Cirúrgicos Minimamente Invasivos , Substituição da Valva Aórtica Transcateter , Estenose da Valva Aórtica/cirurgia , Análise Custo-Benefício , Humanos , Procedimentos Cirúrgicos Minimamente Invasivos/economia , Medição de Risco , Substituição da Valva Aórtica Transcateter/economia
12.
Biochim Biophys Acta ; 1802(11): 1095-104, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-20656023

RESUMO

Prior exposure to sub toxic insults can induce a powerful endogenous neuroprotective program known as ischemic preconditioning. Current models typically rely on a single stress episode to induce neuroprotection whereas the clinical reality is that patients may experience multiple transient ischemic attacks (TIAs) prior to suffering a stroke. We sought to develop a neuron-enriched preconditioning model using multiple oxygen glucose deprivation (OGD) episodes to assess the endogenous protective mechanisms neurons implement at the metabolic and cellular level. We found that neurons exposed to a five minute period of glucose deprivation recovered oxygen utilization and lactate production using novel microphysiometry techniques. Using the non-toxic and energetically favorable five minute exposure, we developed a preconditioning paradigm where neurons are exposed to this brief OGD for three consecutive days. These cells experienced a 45% greater survival following an otherwise lethal event and exhibited a longer lasting window of protection in comparison to our previous in vitro preconditioning model using a single stress. As in other models, preconditioned cells exhibited mild caspase activation, an increase in oxidized proteins and a requirement for reactive oxygen species for neuroprotection. Heat shock protein 70 was upregulated during preconditioning, yet the majority of this protein was released extracellularly. We believe coupling this neuron-enriched multi-day model with microphysiometry will allow us to assess neuronal specific real-time metabolic adaptations necessary for preconditioning.


Assuntos
Adaptação Fisiológica , Glucose/metabolismo , Neurônios/metabolismo , Oxigênio/metabolismo , Animais , Western Blotting , Caspase 3/metabolismo , Hipóxia Celular , Células Cultivadas , Metabolismo Energético/efeitos dos fármacos , Ativação Enzimática/efeitos dos fármacos , Glucose/farmacologia , Proteínas de Choque Térmico HSP70/metabolismo , Imuno-Histoquímica , Neurônios/citologia , Neurônios/efeitos dos fármacos , Oxigênio/farmacologia , Ratos , Ratos Sprague-Dawley , Espécies Reativas de Oxigênio/metabolismo , Estresse Fisiológico , Fatores de Tempo
13.
J Am Med Inform Assoc ; 29(1): 109-119, 2021 12 28.
Artigo em Inglês | MEDLINE | ID: mdl-34791302

RESUMO

OBJECTIVE: Frailty is a prevalent risk factor for adverse outcomes among patients with chronic lung disease. However, identifying frail patients who may benefit from interventions is challenging using standard data sources. We therefore sought to identify phrases in clinical notes in the electronic health record (EHR) that describe actionable frailty syndromes. MATERIALS AND METHODS: We used an active learning strategy to select notes from the EHR and annotated each sentence for 4 actionable aspects of frailty: respiratory impairment, musculoskeletal problems, fall risk, and nutritional deficiencies. We compared the performance of regression, tree-based, and neural network models to predict the labels for each sentence. We evaluated performance with the scaled Brier score (SBS), where 1 is perfect and 0 is uninformative, and the positive predictive value (PPV). RESULTS: We manually annotated 155 952 sentences from 326 patients. Elastic net regression had the best performance across all 4 frailty aspects (SBS 0.52, 95% confidence interval [CI] 0.49-0.54) followed by random forests (SBS 0.49, 95% CI 0.47-0.51), and multi-task neural networks (SBS 0.39, 95% CI 0.37-0.42). For the elastic net model, the PPV for identifying the presence of respiratory impairment was 54.8% (95% CI 53.3%-56.6%) at a sensitivity of 80%. DISCUSSION: Classification models using EHR notes can effectively identify actionable aspects of frailty among patients living with chronic lung disease. Regression performed better than random forest and neural network models. CONCLUSIONS: NLP-based models offer promising support to population health management programs that seek to identify and refer community-dwelling patients with frailty for evidence-based interventions.


Assuntos
Fragilidade , Registros Eletrônicos de Saúde , Fragilidade/diagnóstico , Humanos , Aprendizado de Máquina , Redes Neurais de Computação , Fatores de Risco
14.
J Clin Med Res ; 10(4): 314-320, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29511420

RESUMO

BACKGROUND: Time-driven activity-based costing (TDABC) is a methodology that calculates the costs of healthcare resources consumed as a patient moves along a care process. Limited data exist on the application of TDABC from the perspective of an anesthesia provider. We describe the use of TDABC, a bottom-up costing strategy and financial outcomes for three different medical-surgical procedures. METHODS: In each case, a multi-disciplinary team created process maps describing the care delivery cycle for a patient encounter using the TDABC methodology. Each step in a process map delineated an activity required for delivery of patient care. The resources (personnel, equipment and supplies) associated with each step were identified. A per minute cost for each resource expended was generated, known as the capacity cost rate, and multiplied by its time requirement. The total cost for an episode of care was obtained by adding the cost of each individual resource consumed as the patient moved along a clinical pathway. RESULTS: We built process maps for colonoscopy in the gastroenterology suite, calculated costs of an aortic valve replacement by comparing surgical aortic valve replacement (SAVR) versus transcatheter aortic valve replacement (TAVR) techniques, and determined the cost of carpal tunnel release in an operating room versus an ambulatory procedure room. CONCLUSIONS: TDABC is central to the value-based healthcare platform. Application of TDABC provides a framework to identify process improvements for health care delivery. The first case demonstrates cost-savings and improved wait times by shifting some of the colonoscopies scheduled with an anesthesiologist from the main hospital to the ambulatory facility. In the second case, we show that the deployment of an aortic valve via the transcatheter route front loads the costs compared to traditional, surgical replacement. The last case demonstrates significant cost savings to the healthcare system associated with re-organization of staff required to execute a carpal tunnel release.

15.
Pancreas ; 46(9): 1214-1218, 2017 10.
Artigo em Inglês | MEDLINE | ID: mdl-28902794

RESUMO

OBJECTIVES: This study aimed to determine the prognostic use of the extent of lymph node (LN) involvement in patients with gastroenteropancreatic neuroendocrine tumors (GEP-NETs) by analyzing population-based data. METHODS: Patients in the Surveillance, Epidemiology, and End Results registry were identified with histologically confirmed, surgically resected GEP-NETs. We divided patients into 3 lymph node ratio (LNR) groups based on the ratio of positive LNs to total LNs examined: 0.2 or less, greater than 0.2 to 0.5, and greater than 0.5. Disease-specific survival was compared according to LNR group. RESULTS: We identified 3133 patients with surgically resected GEP-NETs. Primary sites included the stomach (11% of the total), pancreas (30%), colon (32%), appendix (20%), and rectum (7%). Survival was worse in patients with LNRs of 0.2 or less (hazard ratio [HR], 1.5; 95% confidence interval [CI], 1.2-2.0), greater than 0.2 to 0.5 (HR, 2.0; 95% CI, 1.6-2.5), and greater than 0.5 (HR, 3.1; 95% CI, 2.5-3.9) compared with N0 patients. Ten-year disease-specific survival decreased as LNR increased from N0 (81%) to 0.2 or less (69%), greater than 0.2 to 0.5 (55%), and greater than 0.5 (50%). Results were consistent for patients with both low- and high-grade tumors from most primary sites. CONCLUSIONS: Degree of LN involvement is a prognostic factor at the most common GEP-NET sites. Higher LNR is associated with decreased survival.


Assuntos
Neoplasias Intestinais/patologia , Linfonodos/patologia , Tumores Neuroendócrinos/patologia , Neoplasias Pancreáticas/patologia , Neoplasias Gástricas/patologia , Adulto , Idoso , Feminino , Humanos , Estimativa de Kaplan-Meier , Metástase Linfática , Masculino , Pessoa de Meia-Idade , Prognóstico , Estudos Retrospectivos
16.
Eur J Cancer ; 76: 197-204, 2017 05.
Artigo em Inglês | MEDLINE | ID: mdl-28334622

RESUMO

PURPOSE: Current staging criteria for gastroenteropancreatic neuroendocrine neoplasms (GEP-NENs), while useful, have limitations. In this study, we used a population-based registry to evaluate the prognostic utility of the current staging systems and assess whether evidence-based modifications can improve survival predictions. METHODS: We identified patients with confirmed GEP-NENs from the Surveillance, Epidemiology and End Results registry. We assigned tumour-node-metastasis status according to American Joint Committee on Cancer and European Neuroendocrine Tumor Society criteria. We derived a revised staging classification using Kaplan-Meier methods and Cox regression to assess disease-specific survival and compared the accuracy of potential models based on the Akaike Information Criterion (AIC) and Harrell's C-index. The revised classification was validated in an independent set. RESULTS: We identified 10,268 patients with GEP-NENs. We found that multiple stages, as determined by current criteria, misclassified patients' prognosis. In particular, stage IIIB (T1-4N1) had overlapping survival with stage IIIA (T4N0). A revised system which reclassifies N1 disease into different stages based on T status (T1-2N1, T3N1 and T4N1) had an improved AIC (difference = 38) and C-index (0.86) compared to current staging. These revisions improved predictions in patients with both low and high-grade tumours from all primary sites. Results also were confirmed across all primary sites in the validation set. CONCLUSION: Current staging guidelines misclassify the prognosis of N1 patients. Our results suggest that a revised system could lead to better prognostication for GEP-NEN patients. Further validation followed by implementation of these revisions may improve treatment selection and design of clinical trials.


Assuntos
Neoplasias Gastrointestinais/patologia , Tumores Neuroendócrinos/patologia , Neoplasias Pancreáticas/patologia , Adulto , Idoso , Feminino , Neoplasias Gastrointestinais/classificação , Neoplasias Gastrointestinais/mortalidade , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Gradação de Tumores , Estadiamento de Neoplasias , Tumores Neuroendócrinos/classificação , Tumores Neuroendócrinos/mortalidade , Neoplasias Pancreáticas/classificação , Neoplasias Pancreáticas/mortalidade , Prognóstico , Modelos de Riscos Proporcionais , Programa de SEER , Taxa de Sobrevida
18.
J Endourol ; 30(11): 1155-1160, 2016 11.
Artigo em Inglês | MEDLINE | ID: mdl-27758120

RESUMO

INTRODUCTION: Traditional techniques for obtaining percutaneous renal access utilize continuous fluoroscopy. In an attempt to minimize radiation exposure, we describe a novel laser direct alignment radiation reduction technique (DARRT) for percutaneous access and test it in a bench-top model. METHODS: In this randomized-controlled bench-top study, 20 medical personnel obtained renal accesses using both the conventional bullseye technique and the laser DARRT. The primary endpoint was total fluoroscopy time. Secondary endpoints included insertion time, puncture attempts, course corrections, and subjective procedural difficulty. In the laser DARRT, fluoroscopy was used with the C-arm positioned with the laser beam at a 30° angle. The access needle and hub were aligned with the laser beam. Effective caliceal puncture was confirmed with fluoroscopy and direct vision. The Paired samples Wilcoxon signed rank test was used for statistical analysis with significance at p < 0.05. RESULTS: A total of 120 needle placements were recorded. Fluoroscopy time for needle access using the laser DARRT was significantly lower than the bullseye technique in all groups as follows: attendings (7.09 vs 18.51 seconds; p < 0.001), residents (6.55 vs 13.93 seconds; p = 0.001), and medical students (6.69 vs 20.22 seconds; p < 0.001). Students rated the laser DARRT easier to use (2.56 vs 4.89; p < 0.001). No difference was seen in total access time, puncture attempts, or course corrections between techniques. CONCLUSION: The laser DARRT reduced fluoroscopy time by 63%, compared with the conventional bullseye technique. The least experienced users found the laser DARRT significantly easier to learn. This novel technique is promising and merits additional testing in animal and human models.


Assuntos
Fluoroscopia/métodos , Cálices Renais/patologia , Rim/patologia , Lasers , Nefrostomia Percutânea/métodos , Urolitíase/terapia , Adulto , Estudos de Viabilidade , Fluoroscopia/instrumentação , Humanos , Internato e Residência , Rim/cirurgia , Luz , Masculino , Agulhas , Imagens de Fantasmas , Médicos , Estudos Prospectivos , Punções/métodos , Estudantes de Medicina
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