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1.
Chem Rev ; 121(3): 1232-1285, 2021 02 10.
Artículo en Inglés | MEDLINE | ID: mdl-33315380

RESUMEN

Deep eutectic solvents (DESs) are an emerging class of mixtures characterized by significant depressions in melting points compared to those of the neat constituent components. These materials are promising for applications as inexpensive "designer" solvents exhibiting a host of tunable physicochemical properties. A detailed review of the current literature reveals the lack of predictive understanding of the microscopic mechanisms that govern the structure-property relationships in this class of solvents. Complex hydrogen bonding is postulated as the root cause of their melting point depressions and physicochemical properties; to understand these hydrogen bonded networks, it is imperative to study these systems as dynamic entities using both simulations and experiments. This review emphasizes recent research efforts in order to elucidate the next steps needed to develop a fundamental framework needed for a deeper understanding of DESs. It covers recent developments in DES research, frames outstanding scientific questions, and identifies promising research thrusts aligned with the advancement of the field toward predictive models and fundamental understanding of these solvents.

2.
J Magn Reson Imaging ; 56(2): 380-390, 2022 08.
Artículo en Inglés | MEDLINE | ID: mdl-34997786

RESUMEN

BACKGROUND: Preferential publication of studies with positive findings can lead to overestimation of diagnostic test accuracy (i.e. publication bias). Understanding the contribution of the editorial process to publication bias could inform interventions to optimize the evidence guiding clinical decisions. PURPOSE/HYPOTHESIS: To evaluate whether accuracy estimates, abstract conclusion positivity, and completeness of abstract reporting are associated with acceptance to radiology conferences and journals. STUDY TYPE: Meta-research. POPULATION: Abstracts submitted to radiology conferences (European Society of Gastrointestinal and Abdominal Radiology (ESGAR) and International Society for Magnetic Resonance in Medicine (ISMRM)) from 2008 to 2018 and manuscripts submitted to radiology journals (Radiology, Journal of Magnetic Resonance Imaging [JMRI]) from 2017 to 2018. Primary clinical studies evaluating sensitivity and specificity of a diagnostic imaging test in humans with available editorial decisions were included. ASSESSMENT: Primary variables (Youden's index [YI > 0.8 vs. <0.8], abstract conclusion positivity [positive vs. neutral/negative], number of reported items on the Standards for Reporting of Diagnostic Accuracy Studies [STARD] for Abstract guideline) and confounding variables (prospective vs. retrospective/unreported, sample size, study duration, interobserver agreement assessment, subspecialty, modality) were extracted. STATISTICAL TESTS: Multivariable logistic regression to obtain adjusted odds ratio (OR) as a measure of the association between the primary variables and acceptance by radiology conferences and journals; 95% confidence intervals (CIs) and P-values were obtained; the threshold for statistical significance was P < 0.05. RESULTS: A total of 1000 conference abstracts (500 ESGAR and 500 ISMRM) and 1000 journal manuscripts (505 Radiology and 495 JMRI) were included. Conference abstract acceptance was not significantly associated with YI (adjusted OR = 0.97 for YI > 0.8; CI = 0.70-1.35), conclusion positivity (OR = 1.21 for positive conclusions; CI = 0.75-1.90) or STARD for Abstracts adherence (OR = 0.96 per unit increase in reported items; CI = 0.82-1.18). Manuscripts with positive abstract conclusions were less likely to be accepted by radiology journals (OR = 0.45; CI = 0.24-0.86), while YI (OR = 0.85; CI = 0.56-1.29) and STARD for Abstracts adherence (OR = 1.06; CI = 0.87-1.30) showed no significant association. Positive conclusions were present in 86.7% of submitted conference abstracts and 90.2% of journal manuscripts. DATA CONCLUSION: Diagnostic test accuracy studies with positive findings were not preferentially accepted by the evaluated radiology conferences or journals. EVIDENCE LEVEL: 3 TECHNICAL EFFICACY: Stage 2.


Asunto(s)
Publicaciones Periódicas como Asunto , Radiología , Humanos , Estudios Prospectivos , Sesgo de Publicación , Estudios Retrospectivos
3.
AAPS PharmSciTech ; 23(6): 171, 2022 Jun 23.
Artículo en Inglés | MEDLINE | ID: mdl-35739411

RESUMEN

This study aimed to explore the use of chemical and physical enhancement strategies for the intradermal delivery of cromolyn sodium (CS) for treatment of atopic dermatitis. CS gels were formulated to individually contain 2.5 and 9% salcaprozate sodium (SNAC) as a potential chemical enhancer. The effect of microneedles, alone and in combination with SNAC, was investigated via in vitro permeation studies. Skin impedance and FTIR evaluation of SNAC-treated stratum corneum (SC) was done and compared to the control. The amount of drug delivered in the dermis after 24 h by the 2.5% and 9% SNAC gels was 23.29 ± 1.89 µg/cm2 and 35.87 ± 2.23 µg/cm2, respectively, which were significantly higher than the control (p < 0.05) but were not remarkably different from each other (p > 0.05). Microneedles enhanced permeation in both the control and 2.5% SNAC groups (p < 0.05); however, no synergistic enhancement was observed when microneedle and SNAC treatments were combined (p > 0.05). Over 24 h of treating the SC with 2.5% SNAC, FTIR evaluation showed stretches on the CH2 asymmetric and symmetric stretching vibrations observed at 2920.23 cm-1 and 2850.79 cm-1 respectively in untreated SC, which shifted to higher wavenumbers and indicated some lipid fluidizing effect. However, no significant drop in skin impedance was seen with SNAC as compared to the control (p > 0.05). SNAC was concluded to have skin permeation enhancement effect on CS, while microneedles effectively enhanced CS permeation even in the absence of SNAC.


Asunto(s)
Cromolin Sódico , Absorción Cutánea , Administración Cutánea , Geles/metabolismo , Agujas , Piel/metabolismo
4.
Am J Transplant ; 21(12): 4068-4072, 2021 12.
Artículo en Inglés | MEDLINE | ID: mdl-34327815

RESUMEN

Lipoprotein deposition disorders limited to the kidney and causing proteinuria are rare. We present a case of nephrotic range proteinuria presenting within 4 months after deceased donor renal transplantation in a patient with end-stage kidney disease presumed secondary to hypertension. Two transplant kidney biopsies were performed sixteen weeks after transplantation, and one year after the first biopsy, both showing lipoprotein deposits in the glomeruli, progressive focal segmental glomerulosclerosis, and effacement of visceral foot processes. The patient had a normal lipid profile. Based on previous case reports of Apolipoprotein E variants causing proteinuria in native kidneys, Apolipoprotein E genotyping was performed. Genotyping showed Apolipoprotein E2 homozygosity. This Apolipoprotein E variant has been associated with lipoprotein deposition, proteinuria, and progressive kidney disease in the native kidneys. However, this is the first case of Apolipoprotein E2 homozygosity-related kidney disease in a transplant recipient. The patient was treated with fenofibrate, angiotensin enzyme inhibition, and angiotensin receptor blockade with reduction in proteinuria, and he kept good stable kidney function.


Asunto(s)
Glomeruloesclerosis Focal y Segmentaria , Trasplante de Riñón , Aloinjertos , Apolipoproteína E2 , Biopsia , Humanos , Riñón , Trasplante de Riñón/efectos adversos , Masculino , Recurrencia Local de Neoplasia , Proteinuria/etiología
5.
Radiology ; 294(3): 491-505, 2020 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-31990264

RESUMEN

Proposed as a safer alternative to smoking, the use of electronic cigarettes has not proven to be innocuous. With numerous deaths, there is an increasing degree of public interest in understanding the symptoms, imaging appearances, causes of, and treatment of electronic cigarette or vaping product use-associated lung injury (EVALI). Patients with EVALI typically have a nonspecific clinical presentation characterized by a combination of respiratory, gastrointestinal, and constitutional symptoms. EVALI is a diagnosis of exclusion; the patient must elicit a history of recent vaping within 90 days, other etiologies must be eliminated, and chest imaging findings must be abnormal. Chest CT findings in EVALI most commonly show a pattern of acute lung injury on the spectrum of organizing pneumonia and diffuse alveolar damage. The pathologic pattern found depends on when in the evolution of the disease process the biopsy sample is taken. Other less common forms of lung injury, including acute eosinophilic pneumonia and diffuse alveolar hemorrhage, have also been reported. Radiologists and pathologists help play an important role in the evaluation of patients suspected of having EVALI. Accurate and rapid identification may decrease morbidity and mortality by allowing for aggressive clinical management and glucocorticoid administration, which have been shown to decrease the severity of lung injury in some patients. In this review, the authors summarize the current state of the art for the imaging and pathologic findings of this disorder and outline a few of the major questions that remain to be answered.


Asunto(s)
Lesión Pulmonar , Vapeo/efectos adversos , Sistemas Electrónicos de Liberación de Nicotina , Humanos , Lesión Pulmonar/diagnóstico por imagen , Lesión Pulmonar/etiología , Lesión Pulmonar/patología , Lesión Pulmonar/fisiopatología , Tomografía Computarizada por Rayos X
7.
Appl Opt ; 59(17): 5319-5324, 2020 Jun 10.
Artículo en Inglés | MEDLINE | ID: mdl-32543557

RESUMEN

The point spread function (PSF) of an imaging system has a minimum size, a "diffraction limit," determined by the size of the limiting aperture. Image features smaller than this PSF can be, in a conventional imaging system, resolved only if the intensity noise is low enough to permit deconvolution. Measuring image-plane intensity as a function of spatial mode rather than position has the potential to reduce the quantum noise and thus enable subdiffraction resolution at lower light levels or in shorter measurement times than can be tolerated with conventional imaging. Here we examine experimental measurements of intensity and intensity noise as a function of spatial mode. We characterize the impulse response of a spatial mode coupling measurement at the focal plane of an imaging system to the position of a far-field point source. Our measured intensity noise scales with power in a way that suggests photon shot noise is a significant contributor, and we find that the signal-to-noise ratio of our modal-basis measurement of point source position exceeds that of a conventional image-plane pixel array for subdiffraction objects imaged against dark backgrounds. The mode coupling is measured with a custom mode-separating fiber photonic lantern. Photonic lanterns and equivalent structures constructed from rigid waveguides are simple, passive devices that lend themselves to real-world implementations of this measurement scheme with minimal size, weight, power, and cost.

8.
Phys Chem Chem Phys ; 21(7): 3712-3720, 2019 Feb 13.
Artículo en Inglés | MEDLINE | ID: mdl-30334051

RESUMEN

Differential capacitances of ionic liquids (ILs) butyl-trimethylammonium bis(trifluoromethyl sulfonyl)imide, [N1114][TFSI], methyl-propylpyrrolidinium bis(trifluoromethylsulfonyl)imide, [PYR13][TFSI], and ethyl- methylimidazolium bis(trifluoromethylsulfonyl)imide, [EMIM][TFSI], were measured by electrochemical impedance spectroscopy (EIS) over the entire electrochemical window determined by cyclic voltammetry (CV). Distinct fast charging and discharging process frequencies were obtained from the complex capacitance plane extracted from EIS. The onset frequencies of the charging processes were found to be independent of the bulk viscosity of the liquid. [N1114][TFSI] showed the largest relative increase in capacitance with respect to the point of zero charge with applied potential as a result of the 'crowding' effect. This is attributed to a larger degree of rotational freedom associated with the independent alkyl chains and the accessibility of larger potentials with the more stable cation. The largest overall capacitance among the ILs studied was observed for [PYR13][TFSI] at its anodic maximum which occurs due to 'overscreening'. The interpretation of the measured differential capacitance according to the extended mean field theory of Goodwin-Kornyshev [Z. A. Goodwin, et al., Electrochim. Acta., 2017, 225, 190-197] reveals that the ILs with increased ion associations demonstrate the largest relative increase in capacitance with potential.

9.
Radiology ; 308(2): e239022, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-37642574
11.
Eur Respir J ; 52(6)2018 12.
Artículo en Inglés | MEDLINE | ID: mdl-30409817

RESUMEN

Radiological evaluation of incidentally detected lung nodules on computed tomography (CT) influences management. We assessed international radiological variation in 1) pulmonary nodule characterisation; 2) hypothetical guideline-derived management; and 3) radiologists' management recommendations.107 radiologists from 25 countries evaluated 69 CT-detected nodules, recording: 1) first-choice composition (solid, part-solid or ground-glass, with percentage confidence); 2) morphological features; 3) dimensions; 4) recommended management; and 5) decision-influencing factors. We modelled hypothetical management decisions on the 2005 and updated 2017 Fleischner Society, and both liberal and parsimonious interpretations of the British Thoracic Society 2015 guidelines.Overall agreement for first-choice nodule composition was good (Fleiss' κ=0.65), but poorest for part-solid nodules (weighted κ 0.62, interquartile range 0.50-0.71). Morphological variables, including spiculation (κ=0.35), showed poor-to-moderate agreement (κ=0.23-0.53). Variation in diameter was greatest at key thresholds (5 mm and 6 mm). Agreement for radiologists' recommendations was poor (κ=0.30); 21% disagreed with the majority. Although agreement within the four guideline-modelled management strategies was good (κ=0.63-0.73), 5-10% of radiologists would disagree with majority decisions if they applied guidelines strictly.Agreement was lowest for part-solid nodules, while significant measurement variation exists at important size thresholds. These variations resulted in generally good agreement for guideline-modelled management, but poor agreement for radiologists' actual recommendations.


Asunto(s)
Neoplasias Pulmonares/diagnóstico por imagen , Nódulos Pulmonares Múltiples/diagnóstico por imagen , Nódulo Pulmonar Solitario/diagnóstico por imagen , Tomografía Computarizada por Rayos X , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Persona de Mediana Edad , Variaciones Dependientes del Observador , Guías de Práctica Clínica como Asunto , Radiólogos , Reproducibilidad de los Resultados
13.
Radiology ; 305(1): 2-3, 2022 10.
Artículo en Inglés | MEDLINE | ID: mdl-36040338
14.
Radiology ; 303(1): 3-4, 2022 04.
Artículo en Inglés | MEDLINE | ID: mdl-35076299
15.
Radiographics ; 42(2): E37-E38, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35230921
17.
Clin Transplant ; 30(8): 946-53, 2016 08.
Artículo en Inglés | MEDLINE | ID: mdl-27218882

RESUMEN

Renal cell carcinoma (RCC) has a high incidence in the kidney transplant population and annual surveillance detects these tumors early in their natural history. Minimal guidelines exist regarding RCC surveillance in ESRD patients awaiting transplant. A retrospective review of our kidney transplant database examined the outcomes of annual ultrasonographic surveillance during initial kidney transplant evaluation and upon annual reassessment. Of 2642 patients listed for transplant, 145 patients were found to have masses during initial kidney transplant evaluation or annual imaging consistent with new complex cystic disease or RCC. A total of 71 patients had RCC identified, with 52 found on initial kidney transplant evaluation and 19 identified on annual surveillance. Male gender and African-American race were independently associated with RCC (P<.05). RCC was detected a median of 2.0 years after listing (two annual ultrasonography studies). Patients with complex cysts were more likely to undergo transplantation (48.7%) compared to patients with RCC (21.1%; P<.001). There was no significant difference in survival between RCC patients and those found to have complex cystic disease, suggesting incidental RCC can be diagnosed early in the natural history and at a curable stage through implementation of a biennial surveillance program.


Asunto(s)
Carcinoma de Células Renales/diagnóstico , Fallo Renal Crónico/cirugía , Neoplasias Renales/diagnóstico , Trasplante de Riñón , Riñón/diagnóstico por imagen , Ultrasonografía/métodos , Adulto , Anciano , Anciano de 80 o más Años , Carcinoma de Células Renales/complicaciones , Carcinoma de Células Renales/cirugía , Femenino , Estudios de Seguimiento , Humanos , Incidencia , Riñón/cirugía , Fallo Renal Crónico/diagnóstico , Fallo Renal Crónico/etiología , Neoplasias Renales/complicaciones , Neoplasias Renales/cirugía , Masculino , Persona de Mediana Edad , Nefrectomía/métodos , Estudios Retrospectivos , Adulto Joven
18.
Radiographics ; 41(5): E140-E141, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34469210
19.
Radiographics ; 41(2): E63, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33646911
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