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1.
J Am Acad Dermatol ; 2024 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-38936667

RESUMO

The American Academy of Dermatology (AAD) launched DataDerm™ in 2016 as the clinical data registry platform of AAD. DataDerm has evolved to be the largest database in the world containing information about dermatology patients, capturing information about their course of disease, associated therapeutic interventions, and health outcomes. As of December 31, 2022, DataDerm contained data from 14.2 million unique patients and 53.5 million unique patient visits, with 415 practices representing 1,663 clinicians actively participating in DataDerm in 2022. This article is the fourth in a series of Annual Reports about the status of DataDerm. This year's 2023 annual report presents the progress DataDerm has made in conjunction with OM1, the data analytics partner of DataDerm, with a special highlight on the longitudinal care of common dermatologic conditions in the registry and a detailed focus on skin cancer. Furthermore, we review the current status of DataDerm as a robust representation of real world specialty data, reflecting the day-to-day dermatologic care of patients over time.

2.
J Am Acad Dermatol ; 90(1): 106-110, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-37024051

RESUMO

The American Academy of Dermatology (AAD) launched DataDerm in 2016 as the clinical data registry platform of AAD. DataDerm has evolved to be the largest database containing information about dermatology patients in the world. As of December 31, 2021, DataDerm contained data from 13.2 million unique patients and 47.0 million unique patient visits, with 403 practices representing 1670 clinicians actively participating in DataDerm in 2021. Of the 1670 clinicians participating in DataDerm in 2021, the majority were dermatologists (978) followed by physician assistants (375) and nurse practitioners (163) who are employed by AAD members and meet the AAD definition of the AAD DermCare team. Furthermore, in 2021, 834 clinicians submitted data via DataDerm to the Merit-based Incentive Payment System of the Centers for Medicare & Medicaid Services. This article is the third annual report about the status of DataDerm. This year's 2022 annual report presents the progress DataDerm has made over the past year in conjunction with OM1, the data analytics partner of DataDerm, as well as the current status and future plans of DataDerm.


Assuntos
Dermatologia , Profissionais de Enfermagem , Assistentes Médicos , Idoso , Humanos , Estados Unidos , Medicare , Bases de Dados Factuais
3.
J Am Acad Dermatol ; 90(5): 1002-1005, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38135157

RESUMO

BACKGROUND: Medicare's legacy quality reporting programs were consolidated into the Merit-Based Incentive Payment System (MIPS) in 2015. PURPOSE: The DataDerm registry of the American Academy of Dermatology was examined to understand the potential for and subsequent rate of improvement across 23 performance measures. METHODS: We examined the level of performance across 23 performance measures with at least 20 clinicians reporting on at least 50 patients' experience. We calculated the following values: the aggregate performance rate for each measure and the overall aggregate performance rate. RESULTS: The aggregate performance rate for each measure ranged from 20.4% for AAD 1 (Psoriasis: Assessment of Disease Activity), to 99.9% for measure ACMS 1 (Avoidance of Opioid Prescriptions for Reconstruction After Skin Resection). Three of 23 measures had an aggregate performance over 95%. The overall aggregate performance rate across all 23 measures was 81.2%, indicating an aggregate potential for improvement of 18.8% across the 23 measures. Nine performance measures reported across the first five years of DataDerm's existence were tracked through time to understand trends in performance through time. The performance across the nine performance measures meeting the inclusion criteria consistently improved in the initial years (2016 through 2018) of DataDerm participation and showed some variation in 2019 and 2020. CONCLUSIONS: These data provide evidence that the very act of participation in a multi-institutional registry and tracking compliance with performance measures can lead to improvements in compliance with the performance measures and therefore improvements in quality of care.


Assuntos
Medicare , Reembolso de Incentivo , Idoso , Humanos , Estados Unidos , Instalações de Saúde , Motivação
4.
Ear Hear ; 45(4): 915-928, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38389129

RESUMO

OBJECTIVES: Understanding speech in noise (SIN) is the dominant complaint of individuals with hearing loss. For decades, the default test of speech perception in routine audiologic assessment has been monosyllabic word recognition in quiet (WRQ), which does not directly address patient concerns, leading some to advocate that measures of SIN should be integrated into routine practice. However, very little is known with regard to how SIN abilities are affected by different types of hearing loss. Here, we examine performance on clinical measures of WRQ and SIN in a large patient base consisting of a variety of hearing loss types, including conductive (CHL), mixed (MHL), and sensorineural (SNHL) losses. DESIGN: In a retrospective study, we examined data from 5593 patients (51% female) who underwent audiometric assessment at the Stanford Ear Institute. All individuals completed pure-tone audiometry, and speech perception testing of monaural WRQ, and monaural QuickSIN. Patient ages ranged from 18 to 104 years (average = 57). The average age in years for the different classifications of hearing loss was 51.1 (NH), 48.5 (CHL), 64.2 (MHL), and 68.5 (SNHL), respectively. Generalized linear mixed-effect models and quartile regression were used to determine the relationship between hearing loss type and severity for the different speech-recognition outcome measures. RESULTS: Patients with CHL had similar performance to patients with normal hearing on both WRQ and QuickSIN, regardless of the hearing loss severity. In patients with MHL or SNHL, WRQ scores remained largely excellent with increasing hearing loss until the loss was moderately severe or worse. In contrast, QuickSIN signal to noise ratio (SNR) losses showed an orderly systematic decrease as the degree of hearing loss became more severe. This effect scaled with the data, with threshold-QuickSIN relationships absent for CHL, and becoming increasingly stronger for MHL and strongest in patients with SNHL. However, the variability in these data suggests that only 57% of the variance in WRQ scores, and 50% of the variance in QuickSIN SNR losses, could be accounted for by the audiometric thresholds. Patients who would not be differentiated by WRQ scores are shown to be potentially differentiable by SIN scores. CONCLUSIONS: In this data set, conductive hearing loss had little effect on WRQ scores or QuickSIN SNR losses. However, for patients with MHL or SNHL, speech perception abilities decreased as the severity of the hearing loss increased. In these data, QuickSIN SNR losses showed deficits in performance with degrees of hearing loss that yielded largely excellent WRQ scores. However, the considerable variability in the data suggests that even after classifying patients according to their type of hearing loss, hearing thresholds only account for a portion of the variance in speech perception abilities, particularly in noise. These results are consistent with the idea that variables such as cochlear health and aging add explanatory power over audibility alone.


Assuntos
Audiometria de Tons Puros , Perda Auditiva Neurossensorial , Ruído , Percepção da Fala , Humanos , Feminino , Pessoa de Meia-Idade , Masculino , Idoso , Adulto , Estudos Retrospectivos , Idoso de 80 Anos ou mais , Adulto Jovem , Adolescente , Perda Auditiva Neurossensorial/fisiopatologia , Índice de Gravidade de Doença , Perda Auditiva Condutiva/fisiopatologia , Perda Auditiva Condutiva-Neurossensorial Mista/fisiopatologia , Perda Auditiva Condutiva-Neurossensorial Mista/reabilitação , Perda Auditiva/fisiopatologia
5.
Ear Hear ; 45(4): 816-826, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38414136

RESUMO

OBJECTIVES: Self-assessment of perceived communication difficulty has been used in clinical and research practices for decades. Such questionnaires routinely assess the perceived ability of an individual to understand speech, particularly in background noise. Despite the emphasis on perceived performance in noise, speech recognition in routine audiologic practice is measured by word recognition in quiet (WRQ). Moreover, surprisingly little data exist that compare speech understanding in noise (SIN) abilities to perceived communication difficulty. Here, we address these issues by examining audiometric thresholds, WRQ scores, QuickSIN signal to noise ratio (SNR) loss, and perceived auditory disability as measured by the five questions on the Speech Spatial Questionnaire-12 (SSQ12) devoted to speech understanding (SSQ12-Speech5). DESIGN: We examined data from 1633 patients who underwent audiometric assessment at the Stanford Ear Institute. All individuals completed the SSQ12 questionnaire, pure-tone audiometry, and speech assessment consisting of ear-specific WRQ, and ear-specific QuickSIN. Only individuals with hearing threshold asymmetries ≤10 dB HL in their high-frequency pure-tone average (HFPTA) were included. Our primary objectives were to (1) examine the relationship between audiometric variables and the SSQ12-Speech5 scores, (2) determine the amount of variance in the SSQ12-Speech5 scores which could be predicted from audiometric variables, and (3) predict which patients were likely to report greater perceived auditory disability according to the SSQ12-Speech5. RESULTS: Performance on the SSQ12-Speech5 indicated greater perceived auditory disability with more severe degrees of hearing loss and greater QuickSIN SNR loss. Degree of hearing loss and QuickSIN SNR loss were found to account for modest but significant variance in SSQ12-Speech5 scores after accounting for age. In contrast, WRQ scores did not significantly contribute to the predictive power of the model. Degree of hearing loss and QuickSIN SNR loss were also found to have moderate diagnostic accuracy for determining which patients were likely to report SSQ12-Speech5 scores indicating greater perceived auditory disability. CONCLUSIONS: Taken together, these data indicate that audiometric factors including degree of hearing loss (i.e., HFPTA) and QuickSIN SNR loss are predictive of SSQ12-Speech5 scores, though notable variance remains unaccounted for after considering these factors. HFPTA and QuickSIN SNR loss-but not WRQ scores-accounted for a significant amount of variance in SSQ12-Speech5 scores and were largely effective at predicting which patients are likely to report greater perceived auditory disability on the SSQ12-Speech5. This provides further evidence for the notion that speech-in-noise measures have greater clinical utility than WRQ in most instances as they relate more closely to measures of perceived auditory disability.


Assuntos
Audiometria de Tons Puros , Ruído , Razão Sinal-Ruído , Percepção da Fala , Humanos , Masculino , Feminino , Pessoa de Meia-Idade , Adulto , Idoso , Limiar Auditivo , Adulto Jovem , Inquéritos e Questionários , Adolescente , Idoso de 80 Anos ou mais , Perda Auditiva/diagnóstico , Perda Auditiva/fisiopatologia
6.
Ear Hear ; 44(6): 1548-1561, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37703127

RESUMO

OBJECTIVES: For decades, monosyllabic word-recognition in quiet (WRQ) has been the default test of speech recognition in routine audiologic assessment. The continued use of WRQ scores is noteworthy in part because difficulties understanding speech in noise (SIN) is perhaps the most common complaint of individuals with hearing loss. The easiest way to integrate SIN measures into routine clinical practice would be for SIN to replace WRQ assessment as the primary test of speech perception. To facilitate this goal, we predicted classifications of WRQ scores from the QuickSIN signal to noise ratio (SNR) loss and hearing thresholds. DESIGN: We examined data from 5808 patients who underwent audiometric assessment at the Stanford Ear Institute. All individuals completed pure-tone audiometry, and speech assessment consisting of monaural WRQ, and monaural QuickSIN. We then performed multiple-logistic regression to determine whether classification of WRQ scores could be predicted from pure-tone thresholds and QuickSIN SNR losses. RESULTS: Many patients displayed significant challenges on the QuickSIN despite having excellent WRQ scores. Performance on both measures decreased with hearing loss. However, decrements in performance were observed with less hearing loss for the QuickSIN than for WRQ. Most important, we demonstrate that classification of good or excellent word-recognition scores in quiet can be predicted with high accuracy by the high-frequency pure-tone average and the QuickSIN SNR loss. CONCLUSIONS: Taken together, these data suggest that SIN measures provide more information than WRQ. More important, the predictive power of our model suggests that SIN can replace WRQ in most instances, by providing guidelines as to when performance in quiet is likely to be excellent and does not need to be measured. Making this subtle, but profound shift to clinical practice would enable routine audiometric testing to be more sensitive to patient concerns, and may benefit both clinicians and researchers.


Assuntos
Surdez , Percepção da Fala , Humanos , Fala , Ruído , Audição , Audiometria de Tons Puros
7.
Ear Hear ; 44(6): 1540-1547, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37707393

RESUMO

OBJECTIVES: Measures of speech-in-noise, such as the QuickSIN, are increasingly common tests of speech perception in audiologic practice. However, the effect of vestibular schwannoma (VS) on speech-in-noise abilities is unclear. Here, we compare the predictive ability of interaural QuickSIN asymmetry for detecting VS against other measures of audiologic asymmetry. METHODS: A retrospective review of patients in our institution who received QuickSIN testing in addition to a regular audiologic battery between September 2015 and February 2019 was conducted. Records for patients with radiographically confirmed, unilateral, pretreatment VSs were identified. The remaining records excluding conductive pathologies were used as controls. The predictive abilities of various measures of audiologic asymmetry to detect VS were statistically compared. RESULTS: Our search yielded 73 unique VS patients and 2423 controls. Receiver operating characteristic curve analysis showed that QuickSIN asymmetry was more sensitive and specific than pure-tone average asymmetry and word-recognition-in-quiet asymmetry for detecting VS. Multiple logistic regression analysis revealed that QuickSIN asymmetry was more predictive of VS (odds ratio [OR] = 1.23, 95% confidence interval [CI] [1.10, 1.38], p < 0.001) than pure-tone average asymmetry (OR = 1.04, 95% CI [1.00, 1.07], p = 0.025) and word-recognition-in-quiet asymmetry (OR = 1.03, 95% CI [0.99, 1.06], p = 0.064). CONCLUSION: Between-ear asymmetries in the QuickSIN appear to be more efficient than traditional measures of audiologic asymmetry for identifying patients with VS. These results suggest that speech-in noise testing could be integrated into clinical practice without hindering the ability to identify retrocochlear pathology.


Assuntos
Neuroma Acústico , Percepção da Fala , Humanos , Fala , Neuroma Acústico/diagnóstico , Ruído , Valores de Referência , Estudos Retrospectivos
8.
Anal Chem ; 94(36): 12297-12304, 2022 09 13.
Artigo em Inglês | MEDLINE | ID: mdl-36018813

RESUMO

Dynamic observation of cell and tissue responses to elevated pressure could help our understanding of important physiological and pathological processes related to pressure-induced injury. Here, we report on a microfluidic platform capable of maintaining a wide range of stable operating pressures (30 to 200 mmHg) while using a low flowrate (2-14 µL/h) to limit shear stress. This is achieved by forcing flow through a porous resistance matrix composed of agarose gel downstream of a microfluidic chamber. The flow characteristics were investigated and the permeabilities of the agarose with four different concentrations were extracted, agreeing well with results found in the literature. To demonstrate the capability of the device, we measured the change in intracellular Ca2+ levels of retinal ganglion cells in whole mouse retina in response to pressure. The onset of enhanced pressure results in, on average, an immediate 119.16% increase in the intracellular Ca2+ levels of retinal ganglion cells. The demonstrated microfluidic platform could be widely used to probe cell and tissue responses to elevated pressure.


Assuntos
Microfluídica , Retina , Animais , Camundongos , Células Ganglionares da Retina/patologia , Células Ganglionares da Retina/fisiologia , Sefarose , Estresse Mecânico
9.
J Am Acad Dermatol ; 86(2): 394-398, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34126095

RESUMO

The utility of any database or registry depends on the completeness and accuracy of the data it contains. This report documents the validity of data elements within DataDerm, the clinical registry database of the American Academy of Dermatology. An external audit of DataDerm, performed by a third-party vendor, involved the manual review of 1098 individual patient charts from calendar year 2018 from 8 different dermatology practices that used 4 different electronic health records. At each site, 142 discrete data fields were assessed, comparing the data within DataDerm to the source data within the electronic health record. Audited data included 3 domains of data elements (diagnoses, medications, and procedures) and a performance measure ("Biopsy Reporting Time-Clinician to Patient"), which is 1 of several measures used by DataDerm as a Qualified Clinical Data Registry. Overall completeness of data was 95.3%, with a range among practices of 90.6% to 98.5%. Overall accuracy of data was 89.8%, with a range of accuracy among practices of 81.2% to 94.1%. These levels of completeness and accuracy exceed the rates in the literature for registries that are based on data that is extracted from electronic health records; and therefore, this audit validates the excellent quality of data in DataDerm.


Assuntos
Dermatologia , Academias e Institutos , Coleta de Dados , Bases de Dados Factuais , Humanos , Sistema de Registros , Estados Unidos
10.
J Am Acad Dermatol ; 86(5): 1058-1062, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-34838686

RESUMO

The American Academy of Dermatology launched DataDerm in 2016 as the clinical data registry platform of the American Academy of Dermatology. DataDerm has evolved to be the largest database containing information about dermatology patients in the world. As of December 31, 2020, DataDerm contained data from 11.3 million unique patients and 40.0 million unique patient visits, with 782 practices representing 2290 clinicians actively participating in DataDerm. This article is the second in a series of annual reports about the status of DataDerm. While last year's 2020 first annual report presented the history of DataDerm as well as the rationale for its creation, maintenance, and expansion, this year's 2021 annual report presents the progress DataDerm has made over the past year along with its current status and future plans.


Assuntos
Dermatologia , Academias e Institutos , Bases de Dados Factuais , Previsões , Humanos , Sistema de Registros , Estados Unidos
11.
Nano Lett ; 21(17): 7317-7324, 2021 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-34415746

RESUMO

Enhancing the thermal conductivity of polymer composites could improve their performance in applications requiring fast heat dissipation. While significant progress has been made, a long-standing issue is the contact thermal resistance between the nanofillers, which could play a critical role in the composite thermal properties. Through systematic studies of contact thermal resistance between individual boron nitride nanotubes (BNNTs) of different diameters, with and without a poly(vinylpyrrolidone) (PVP) interlayer, we show that the contact thermal resistance between bare BNNTs is largely determined by reflection of ballistic phonons. Interestingly, it is found that a PVP interlayer can either enhance or reduce the contact thermal resistance, as a result of converting the ballistic phonon dominated transport into diffusion through the PVP layer. These results disclose a previously unrecognized physical picture of thermal transport at the contact between BNNTs, which provides insights into the design of high thermal conductivity BNNT-polymer composites.

12.
Nano Lett ; 21(10): 4388-4393, 2021 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-33955762

RESUMO

Various nanofillers have been adopted to enhance the thermal conductivity of polymer nanocomposites. While it is widely believed that the contact thermal resistance between adjacent nanofillers can play an important role in limiting thermal conductivity enhancement of composite materials, lack of direct experimental data poses a significant challenge to perceiving the effects of these contacts. This study reports on direct measurements of thermal transport through contacts between silver nanowires (AgNWs) with a poly(vinylpyrrolidone) (PVP) interlayer. The results indicate that a PVP layer as thin as 4 nm can increase the total thermal resistance of the contact by up to an order of magnitude, when compared to bare AgNWs, even with a larger contact area. On the other hand, the thermal boundary resistance for PVP/silver interfaces could be significantly lower than that between polymer-carbon nanotubes (CNTs). Analyses based on these understandings further show why AgNWs could be more effective nanofillers than CNTs.

13.
J Am Acad Dermatol ; 84(4): 1037-1041, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33316331

RESUMO

The American Academy of Dermatology launched DataDerm in 2016 as the clinical data registry platform of the American Academy of Dermatology. DataDerm is approved by the Centers for Medicare & Medicaid Services as a Qualified Clinical Data Registry for the Merit-Based Incentive Payment System. The ultimate purpose of DataDerm is to provide dermatologists with a registry and database that will serve as a vehicle to advance the specialty in the domains of science, discovery, education, quality assessment, quality improvement, advocacy, and practice management. DataDerm is currently the largest clinical registry and database of patients receiving dermatologic care in the world. As of December 31, 2019, DataDerm contained data from 10,618,879 unique patients and 32,309,389 unique patient visits. Depending on the reporting period, 800 to 900 practices (representing 2400-2600 clinicians) actively participate in DataDerm by submitting data. This article provides the first of a planned series of annual updates of the status of DataDerm. The purpose of this article is to present the rationale for the creation, maintenance, history, and current status of DataDerm, as well as the future plans for DataDerm.


Assuntos
Academias e Institutos , Relatórios Anuais como Assunto , Bases de Dados Factuais , Dermatologia , Sistema de Registros , Previsões , Humanos , Internacionalidade , Estados Unidos
14.
Nano Lett ; 20(10): 7389-7396, 2020 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-32833462

RESUMO

Silver nanowires have been widely adopted as nanofillers in composite materials used for various applications. Electrical and thermal properties of these composites are critical for proper device operation, and highly depend on transport through the nanowires and their contacts, yet studies on silver nanowires have been limited to one or two samples and no solid data have been reported for individual contacts. Through systematic measurements of silver nanowires of different sizes, we show that the Lorenz number increases with decreasing wire diameter and has a higher value at wire contacts. Examination of the corresponding electrical and thermal conductivities indicates that these changes are due to contributions of phonons that become more important as a result of elastic stiffening. The derived contact thermal conductance per unit area between silver nanowires is ∼10 times that between carbon nanotubes. This helps to explain the more significant thermal conductivity enhancement of silver nanowires-based composites.

15.
J Proteome Res ; 19(7): 2585-2597, 2020 07 02.
Artigo em Inglês | MEDLINE | ID: mdl-32227958

RESUMO

Synovial fluid (SF) is of great interest for the investigation of orthopedic pathologies, as it is in close proximity to various tissues that are primarily altered during these disease processes and can be collected using minimally invasive protocols. Multi-"omic" approaches are commonplace, although little consideration is often given for multiple analysis techniques at sample collection. Nuclear magnetic resonance (NMR) metabolomics and liquid chromatography tandem mass spectrometry (LC-MS/MS) proteomics are two complementary techniques particularly suited to the study of SF. However, currently there are no agreed upon standard protocols that are published for SF collection and processing for use with NMR metabolomic analysis. Furthermore, the large protein concentration dynamic range present within SF can mask the detection of lower abundance proteins in proteomics. While combinational ligand libraries (ProteoMiner columns) have been developed to reduce this dynamic range, their reproducibility when used in conjunction with SF, or on-bead protein digestion protocols, has yet to be investigated. Here we employ optimized protocols for the collection, processing, and storage of SF for NMR metabolite analysis and LC-MS/MS proteome analysis, including a Lys-C endopeptidase digestion step prior to tryptic digestion, which increased the number of protein identifications and improved reproducibility for on-bead ProteoMiner digestion.


Assuntos
Proteômica , Espectrometria de Massas em Tandem , Cromatografia Líquida , Espectroscopia de Ressonância Magnética , Metabolômica , Reprodutibilidade dos Testes , Líquido Sinovial
16.
J Am Acad Dermatol ; 82(6): 1487-1489, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31972259

RESUMO

The American Academy of Dermatology is modernizing its clinical practice guidelines to be more timely and easily interpretable, while decreasing the influence of conflicts of interest in guideline generation. The main changes include the transition from SORT to GRADE methodology and the requirement that nonconflicted members of the guideline work groups remain nonconflicted throughout the entire guidelines process.


Assuntos
Dermatologia , Guias de Prática Clínica como Assunto/normas , Estados Unidos
17.
Biomed Microdevices ; 21(1): 26, 2019 03 02.
Artigo em Inglês | MEDLINE | ID: mdl-30826983

RESUMO

Polydimethylsiloxane (PDMS) has been the pivotal materials for microfluidic technologies with tremendous amount of lab-on-a-chip devices made of PDMS microchannels. While molding-based soft-lithography approach has been extremely successful in preparing various PDMS constructs, some complex features have to been achieved through more complicated microfabrication techniques that involve dry etching of PDMS. Several recipes have been reported for reactive ion etching (RIE) of PDMS; however, the etch rates present large variations, even for the same etching recipe, which poses challenges in adopting this process for device fabrication. Through systematic characterization of the Young's modulus of PDMS films and RIE etch rate, we show that the etch rate is closely related to the polymer cross-link density in the PDMS with a higher etch rate for a lower PDMS Young's modulus. Our results could provide guidance to the fabrication of microfluidic devices involving dry etching of PDMS.


Assuntos
Dimetilpolisiloxanos/química , Módulo de Elasticidade , Dispositivos Lab-On-A-Chip
18.
Arterioscler Thromb Vasc Biol ; 38(2): 457-463, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29217508

RESUMO

OBJECTIVE: Abdominal aortic aneurysms are inflammatory in nature and are associated with some risk factors that also lead to atherosclerotic occlusive disease, most notably smoking. The purpose of our study was to identify differential cytokine expression in patients with abdominal aortic aneurysm and those with atherosclerotic occlusive disease. Based on this analysis, we further explored and compared the mechanism of action of IL (interleukin)-1ß versus TNF-α (tumor necrosis factor-α) in abdominal aortic aneurysm formation. APPROACH AND RESULTS: IL-1ß was differentially expressed in human plasma with lower levels detected in patients with abdominal aortic aneurysm compared with matched atherosclerotic controls. We further explored its mechanism of action using a murine model and cell culture. Genetic deletion of IL-1ß and IL-1R did not inhibit aneurysm formation or decrease MMP (matrix metalloproteinase) expression. The effects of IL-1ß deletion on M1 macrophage polarization were compared with another proinflammatory cytokine, TNF-α. Bone marrow-derived macrophages from IL-1ß-/- and TNF-α-/- mice were polarized to an M1 phenotype. TNF-α deletion, but not IL-1ß deletion, inhibited M1 macrophage polarization. Infusion of M1 polarized TNF-α-/- macrophages inhibited aortic diameter growth; no inhibitory effect was seen in mice infused with M1 polarized IL-1ß-/- macrophages. CONCLUSIONS: Although IL-1ß is a proinflammatory cytokine, its effects on aneurysm formation and macrophage polarization differ from TNF-α. The differential effects of IL-1ß and TNF-α inhibition are related to M1/M2 macrophage polarization and this may account for the differences in clinical efficacy of IL-1ß and TNF-α antibody therapies in management of inflammatory diseases.


Assuntos
Aorta Abdominal/metabolismo , Aneurisma da Aorta Abdominal/metabolismo , Interleucina-1beta/metabolismo , Ativação de Macrófagos , Macrófagos/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Idoso , Animais , Aorta Abdominal/patologia , Aneurisma da Aorta Abdominal/patologia , Estudos de Casos e Controles , Dilatação Patológica , Modelos Animais de Doenças , Feminino , Humanos , Interleucina-1beta/sangue , Interleucina-1beta/deficiência , Interleucina-1beta/genética , Macrófagos/patologia , Macrófagos/transplante , Masculino , Camundongos da Linhagem 129 , Camundongos Endogâmicos C57BL , Camundongos Knockout , Pessoa de Meia-Idade , Fenótipo , Receptores de Interleucina-1/genética , Receptores de Interleucina-1/metabolismo , Transdução de Sinais , Fator de Necrose Tumoral alfa/deficiência , Fator de Necrose Tumoral alfa/genética
19.
Soft Matter ; 14(47): 9534-9541, 2018 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-30376032

RESUMO

Understanding and enhancing thermal transport in polymers is of great importance, and is necessary to enable next-generation flexible electronics, heat exchangers, and energy storage devices. Over the past several decades, significant enhancement of the thermal conductivity of polymeric materials has been achieved, but several key questions related to the effects of molecular structure on thermal transport still remain. By studying a series of electrospun vinyl polymer nanofibers, we investigate the relationship between thermal conductivity and both molecular chain length and side group composition. For polyethylene nanofibers with different molecular weights, the measured thermal conductivity increases monotonically with molecular chain length, as energy transport along molecular chains is more efficient than between chains. The observed trend is also consistent with structural characterization by Raman spectroscopy, which shows enhanced crystallinity as molecular weight increases. Further, by comparing the measured thermal conductivity of vinyl polymer nanofibers with different side groups, we found that phonons travel along polymer chains more effectively when the side groups are either lighter or more symmetric. These experimental results help reveal the underlying correlation between the molecular structure and thermal conductivity of polymer nanofibers, providing valuable insights into the design of polymeric materials with enhanced thermal conductivity.

20.
J Acoust Soc Am ; 142(4): 2043, 2017 10.
Artigo em Inglês | MEDLINE | ID: mdl-29092596

RESUMO

Detection of a tonal signal in amplitude-modulated noise can improve with increases in noise bandwidth if the pattern of amplitude fluctuations is uniform across frequency, a phenomenon termed comodulation masking release (CMR). Most explanations for CMR rely on an assumption that listeners monitor frequency channels both at and remote from the signal frequency in conditions that yield the effect. To test this assumption, detectability was assessed for signals presented at expected and unexpected frequencies in wideband amplitude-modulated noise. Detection performance was high even for signals of unexpected frequency, suggesting that listeners were monitoring multiple frequency channels, as has been assumed.

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