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1.
J Drugs Dermatol ; 23(5): 306-310, 2024 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-38709694

RESUMEN

BACKGROUND: There are no guidelines on when to more strongly recommend sentinel lymph node biopsy (SLNB) for T1b melanomas. OBJECTIVE: To examine whether anatomic locations of T1b melanomas and patient age influence metastases. METHODS: We conducted a retrospective study using data from two hospitals in Los Angeles County from January 2010 through January 2020. RESULTS: Out of 620 patients with primary melanomas, 566 melanomas were staged based on the American Joint Committee on Cancer 8th edition melanoma staging. Forty-one were T1b, of which 13 were located on the face/ear/scalp and 28 were located elsewhere. T1b melanomas located on the face/ear/scalp had an increased risk of lymph node or distant metastasis compared with other anatomic sites (31% vs 3.6%, P=0.028). For all melanomas, the risk of lymph node or distant metastasis decreased with age of 64 years or greater (P<0.001 and P=0.034). For T1b melanomas, the risk of distant metastasis increased with increasing age (P=0.047). LIMITATIONS: Data were from a single county.  Conclusion: T1b melanomas of the face/ear/scalp demonstrated a higher risk of lymph node or distant metastasis and may help guide the recommendation of SLNB, imaging, and surveillance. Younger patients may be more strongly considered for SLNB and older patients with T1b melanomas may warrant imaging.  J Drugs Dermatol. 2024;23(5):306-310. doi:10.36849/JDD.7667.


Asunto(s)
Metástasis Linfática , Melanoma , Estadificación de Neoplasias , Biopsia del Ganglio Linfático Centinela , Neoplasias Cutáneas , Humanos , Melanoma/patología , Melanoma/diagnóstico , Melanoma/epidemiología , Estudios Retrospectivos , Femenino , Neoplasias Cutáneas/patología , Neoplasias Cutáneas/diagnóstico , Neoplasias Cutáneas/epidemiología , Masculino , Persona de Mediana Edad , Anciano , Factores de Edad , Metástasis Linfática/diagnóstico , Adulto , Anciano de 80 o más Años , Los Angeles/epidemiología , Adulto Joven
2.
Adv Mater ; : e2401349, 2024 Apr 24.
Artículo en Inglés | MEDLINE | ID: mdl-38657644

RESUMEN

Phonon polaritons, the hybrid quasiparticles resulting from the coupling of photons and lattice vibrations, have gained significant attention in the field of layered van der Waals heterostructures. Particular interest has been paid to hetero-bicrystals composed of molybdenum oxide (MoO3) and hexagonal boron nitride (hBN), which feature polariton dispersion tailorable via avoided polariton mode crossings. In this work, we systematically study the polariton eigenmodes in MoO3-hBN hetero-bicrystals self-assembled on ultrasmooth gold using synchrotron infrared nanospectroscopy. We experimentally demonstrate that the spectral gap in bicrystal dispersion and corresponding regimes of negative refraction can be tuned by material layer thickness, and we quantitatively match these results with a simple analytic model. We also investigate polaritonic cavity modes and polariton propagation along "forbidden" directions in our microscale bicrystals, which arise from the finite in-plane dimension of the synthesized MoO3 micro-ribbons. Our findings shed light on the unique dispersion properties of polaritons in van der Waals heterostructures and pave the way for applications leveraging deeply sub-wavelength mid-infrared light matter interactions. This article is protected by copyright. All rights reserved.

4.
Sci Adv ; 10(12): eadk6369, 2024 Mar 22.
Artículo en Inglés | MEDLINE | ID: mdl-38507493

RESUMEN

Excitons-bound electron-hole pairs-play a central role in light-matter interaction phenomena and are crucial for wide-ranging applications from light harvesting and generation to quantum information processing. A long-standing challenge in solid-state optics has been to achieve precise and scalable control over excitonic motion. We present a technique using nanostructured gate electrodes to create tailored potential landscapes for excitons in 2D semiconductors, enabling in situ wave function shaping at the nanoscale. Our approach forms electrostatic traps for excitons in various geometries, such as quantum dots, rings, and arrays thereof. We show independent spectral tuning of spatially separated quantum dots, achieving degeneracy despite material disorder. Owing to the strong light-matter coupling of excitons in 2D semiconductors, we observe unambiguous signatures of confined exciton wave functions in optical reflection and photoluminescence measurements. This work unlocks possibilities for engineering exciton dynamics and interactions at the nanometer scale, with implications for optoelectronic devices, topological photonics, and quantum nonlinear optics.

5.
Artículo en Inglés | MEDLINE | ID: mdl-38534072

RESUMEN

PURPOSE: This cross-sectional prospective study measured utility values of upper eyelid dermatochalasis to quantify its impact on quality of life and assess cost-effectiveness of upper blepharoplasty. METHODS: Utility of dermatochalasis was assessed using the standard reference gamble and time trade-off methods, with dual anchor points of perfect eye function and perfect health. The utility value obtained was used to create a Markov model and run a cost-effectiveness analysis of blepharoplasty as a treatment for dermatochalasis while utilizing the societal perspective. RESULTS: One hundred three patients with dermatochalasis recruited from an urban outpatient ophthalmology clinic completed the utility survey. The authors determined utility values for dermatochalasis ranging from 0.74 to 0.92 depending on the measurement method (standard reference gamble/time trade-off) and anchor points. The cost-effectiveness analysis yielded an incremental cost-effectiveness ratio of $3,146 per quality-adjusted life year, well under the conventional willingness-to-pay threshold of $50,000 per quality-adjusted life year. Probabilistic sensitivity analysis with Monte Carlo simulation demonstrated that blepharoplasty would be cost-effective in 88.1% of cases at this willingness-to-pay threshold. CONCLUSIONS: Dermatochalasis has an impact on quality of life that is significantly associated with level of perceived functional impairment. Rising health care costs have underscored the importance of providing value-based treatment to patients, and the results of this study suggest that blepharoplasty is a cost-effective treatment option for symptomatic bilateral upper eyelid dermatochalasis.

6.
Graefes Arch Clin Exp Ophthalmol ; 262(5): 1531-1538, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-37999774

RESUMEN

PURPOSE: To determine how high myopia impacts pharmacological pupillary dilation, and to evaluate the relationship between the extent of pharmacologic pupillary dilation and axial length. METHODS: Patients were grouped into high myopes, defined as one or both eyes having a refractive error greater than - 6 diopters, and controls (between - 2 and + 2 diopters). Dilation was achieved with 1 drop each of tropicamide 1% and phenylephrine 2.5%. Pupil size was measured at full and dim light prior to dilation, then 15 and 30 min after dilation. Biometry was measured for each patient. Statistical analyses were performed using the Mann-Whitney-Wilcoxon tests, two-sample Welch's t-tests, and linear mixed effect models and generalized estimating equations models accounting for inter-eye correlation. RESULTS: Forty patients (20 high myopes and 20 controls, 80 eyes total) participated in the study. High myopes had larger pupils at baseline and achieved significantly greater pupillary size (7.08 mm, 95% CI: 6.97 to 7.19 mm) than controls (6.23 mm, 95% CI: 5.94 to 6.52 mm) after 30 min of dilation (P < .0005). Fully dilated pupil size at 30 min was significantly correlated with both refractive error (r = - 0.57, P < .0005) and axial length (r = 0.47, P < .0005). Generalized estimating equations and linear mixed effect models identified other predictive variables of pupil size after dilation including age and white-to-white diameter. CONCLUSIONS: Highly myopic patients dilate to a larger pupillary size compared to other patients. Predicting dilation based on extent of myopia could facilitate intraocular surgery planning and reduce clinic wait times for myopic patients.

7.
J Refract Surg ; 39(11): 777-782, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37937762

RESUMEN

PURPOSE: To analyze the cost-effectiveness of the Light Adjustable Lens (LAL; RxSight) in comparison to a monofocal intraocular lens (IOL) for individuals undergoing cataract surgery in both eyes. METHODS: A cost-effectiveness analysis was performed using a Markov model that simulated the patient outcomes and costs associated with undergoing cataract surgery with the LAL or monofocal IOL. Cost-effectiveness was determined using the incremental cost-effectiveness ratio (ICER), a measure that quantifies the incremental cost in dollars per quality-adjusted life year (QALY) gained. Treatments with the ICER below the willingness-to-pay threshold (WTP) of $50,000/QALY were considered cost-effective. The model was also evaluated for the impact of uncertainties in parameters using one-way sensitivity and probabilistic sensitivity analyses. RESULTS: The cost-effectiveness analysis showed that the LAL is cost-effective compared to monofocal IOLs in patients undergoing cataract surgery, with ICERs of $9,792/QALY (health care perspective) and $10,072/QALY (societal perspective) both significantly below the WTP. The model was most sensitive to patient age, market cost of the LAL, and proportion of patients with residual astigmatism following cataract surgery. The probabilistic sensitivity analysis showed that cataract surgeries in patients starting at age 65 years were cost-effective in 94% of the simulations at a WTP of $50,000/QALY. CONCLUSIONS: From both health care and societal perspectives, the study shows cataract surgeries performed with the LAL are cost-effective when compared to those performed with a monofocal IOL. More studies are needed to compare the LAL to other premium lenses that also provide patients with excellent visual outcomes at a higher cost. [J Refract Surg. 2023;39(11):777-782.].


Asunto(s)
Catarata , Lentes Intraoculares , Humanos , Anciano , Implantación de Lentes Intraoculares , Análisis de Costo-Efectividad , Agudeza Visual , Análisis Costo-Beneficio
8.
Nat Mater ; 22(12): 1485-1491, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37857888

RESUMEN

Van der Waals (vdW) materials have opened up many avenues for discovery through layer assembly, as epitomized by interlayer dipolar excitons that exhibit electrically tunable luminescence, lasing and exciton condensation. Extending interlayer excitons to more vdW layers, however, raises fundamental questions concerning coherence within excitons and coupling between moiré superlattices at multiple interfaces. Here, by assembling angle-aligned WSe2/WS2/WSe2 heterotrilayers, we demonstrate the emergence of quadrupolar excitons. We confirm the exciton's quadrupolar nature by the decrease in its energy of 12 meV from coherent hole tunnelling between the two outer layers, its tunable static dipole moment under an external electric field and the reduced exciton-exciton interactions. At high exciton density, we also see signatures of a phase of oppositely aligned dipolar excitons, consistent with a staggered dipolar phase predicted to be driven by attractive dipolar interactions. Our demonstration paves the way for discovering emergent exciton orderings for three vdW layers and beyond.

9.
Nano Lett ; 23(21): 10051-10057, 2023 Nov 08.
Artículo en Inglés | MEDLINE | ID: mdl-37903015

RESUMEN

Strain provides a powerful method to study 2D monolayers and to tune their properties. The same approach also has great potential for van-der-Waals (vdW) heterostructures. However, we need to understand how strain can be applied to vertically stacked vdW structures, for which strain transfer from one layer to the next remains little explored. In our experiment, we fabricated vertical heterostructures consisting of transition metal dichalcogenides (TMDCs) monolayers that were deposited on a flexible substrate. These TMDC heterostructures allowed us to read out separately the strain in each monolayer by photoluminescence measurements. We find that, in TMDC heterostructures with large twist angles (>5°), strain transfer is limited. However, for aligned heterostructures with small twist angles (≤5°), near unity strain transfer efficiency is observed. We correlate this finding with the moiré domains formed in the aligned heterostructures by reconstruction.

11.
Can J Ophthalmol ; 2023 Mar 28.
Artículo en Inglés | MEDLINE | ID: mdl-37001560

RESUMEN

OBJECTIVE: To determine the cost-effectiveness of endoscopic dacryocystorhinostomy (DCR). METHODS: We constructed a Markov model in which patients with nasolacrimal duct obstruction received endoscopic DCR or no surgery. Incremental cost-effectiveness ratios, 1-way sensitivity analyses, and probabilistic sensitivity analyses were used to evaluate for model sensitivity to multiple model inputs. RESULTS: Endoscopic DCR was found to be cost-effective with an incremental cost-effectiveness ratio of US$2162 per quality-adjusted life-year. The model was most sensitive to the health utility deduction from epiphora. Probabilistic sensitivity analysis found endoscopic DCR to be cost-effective over no surgery 93.7% of the time. CONCLUSIONS: Endoscopic DCR is a cost-effective treatment for patients with epiphora. The model is very sensitive to the negative effect epiphora has on quality of life. With the advancement of health care technology and surgical techniques, the success rates of endoscopic DCR continue to improve and to be an even more efficacious and economical treatment for nasolacrimal duct obstruction.

13.
Arch Dermatol Res ; 315(5): 1449-1452, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-36456760

RESUMEN

Cosmetic and laser procedures are increasingly popular among patients and are skills in which dermatologists are regarded as well trained. Most dermatology residents intend to incorporate cosmetic procedures into their practice and prefer to learn such procedures during residency through direct patient care. However, there are notable challenges in optimizing how residents are trained in cosmetic and laser dermatology. To address these barriers and elevate the practice of cosmetic dermatology in academic medicine, the Association of Academic Cosmetic Dermatology (AACD) was founded in 2021 as the lead professional society for dermatologists who direct the education of resident trainees in cosmetic and laser dermatology. The AACD, a group of board-certified dermatologists who teach cosmetic and laser dermatology to residents, aims to improve cosmetic dermatology education through collaboration, research, and advocacy.


Asunto(s)
Dermatología , Internado y Residencia , Humanos , Dermatología/educación , Curriculum , Encuestas y Cuestionarios
14.
Arch Dermatol Res ; 315(6): 1755-1762, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-36463367

RESUMEN

Cosmetic dermatology is a key subspecialty of academic dermatology. As such, academic centers are expected to demonstrate excellence in the teaching of cosmetic dermatology skills to trainees, the clinical delivery of cosmetic dermatology services to patients, and the performance of clinical research that advances knowledge and uncovers new therapies in cosmetic dermatology. The Association of Academic Cosmetic Dermatology (AACD), a newly formed medical professional society, includes as its principal aims the support of all of these areas. AACD is comprised of group of board-certified dermatologists who teach cosmetic and laser dermatology at US dermatology residency programs. An expert panel constituted by the AACD recently convened a workshop to review gaps pertaining to academic cosmetic dermatology. This panel considered needs and potential corrective initiatives in three domains: resident education, patient experience, and clinical research. The work of the panel was used to develop a roadmap, which was adopted by consensus, and which will serve to guide the AACD moving forward.


Asunto(s)
Dermatología , Internado y Residencia , Humanos , Dermatología/educación , Atención al Paciente , Sociedades Médicas
15.
Nano Lett ; 22(20): 8389-8393, 2022 10 26.
Artículo en Inglés | MEDLINE | ID: mdl-36112673

RESUMEN

Sharp resonances can strongly modify the electromagnetic response of matter. A classic example is the Reststrahlen effect - high reflectivity in the mid-infrared in many polar crystals near their optical phonon resonances. Although this effect in bulk materials has been studied extensively, a systematic treatment for finite thickness remains challenging. Here we describe, experimentally and theoretically, the Reststrahlen response in hexagonal boron nitride across more than 5 orders of magnitude in thickness, down to a monolayer. We find that the high reflectivity plateau of the Reststrahlen band evolves into a single peak as the material enters the optically thin limit, within which two distinct regimes emerge: a strong-response regime dominated by coherent radiative decay and a weak-response regime dominated by damping. We show that this evolution can be explained by a simple two-dimensional sheet model that can be applied to a wide range of thin media.


Asunto(s)
Fonones , Vibración
18.
J Immunother Cancer ; 10(5)2022 05.
Artículo en Inglés | MEDLINE | ID: mdl-35545318

RESUMEN

BACKGROUND: Basal cell carcinoma (BCC) is the most common malignancy worldwide, yet the management of patients with advanced or metastatic disease is challenging, with limited treatment options. Recently, programmed death receptor 1 (PD-1) inhibition has demonstrated activity in BCC after prior Hedgehog inhibitor treatment. METHODS: We conducted a multicenter, retrospective analysis of BCC patients treated with PD-1 inhibitor therapy. We examined the efficacy and safety of PD-1 therapy, as well as clinical and pathological variables in association with outcomes. Progression-free survival (PFS), overall survival (OS) and duration of response (DOR) were calculated using Kaplan-Meier methodology. Toxicity was graded per Common Terminology Criteria for Adverse Events V.5.0. RESULTS: A total of 29 patients with BCC who were treated with PD-1 inhibition were included for analysis, including 20 (69.0%) with locally advanced and 9 (31.0%) with metastatic disease. The objective response rate was 31.0%, with five partial responses (17.2%), and four complete responses (13.8%). Nine patients had stable disease (31.0%), with a disease control rate of 62.1%. The median DOR was not reached. Median PFS was 12.2 months (95% CI 0.0 to 27.4). Median OS was 32.4 months (95% CI 18.1 to 46.7). Two patients (6.9%) developed grade 3 or higher toxicity, while four patients (13.8%) discontinued PD-1 inhibition because of toxicity. Higher platelets (p=0.022) and any grade toxicity (p=0.024) were significantly associated with disease control rate. CONCLUSIONS: The clinical efficacy of PD-1 inhibition among patients with advanced or metastatic BCC in this real-world cohort were comparable to published trial data. Further investigation of PD-1 inhibition is needed to define its optimal role for patients with this disease.


Asunto(s)
Carcinoma Basocelular , Neoplasias Cutáneas , Carcinoma Basocelular/tratamiento farmacológico , Carcinoma Basocelular/patología , Proteínas Hedgehog , Humanos , Receptor de Muerte Celular Programada 1/uso terapéutico , Estudios Retrospectivos , Neoplasias Cutáneas/tratamiento farmacológico , Neoplasias Cutáneas/patología
19.
Nature ; 603(7900): 247-252, 2022 03.
Artículo en Inglés | MEDLINE | ID: mdl-35264760

RESUMEN

Interlayer excitons (ILXs) - electron-hole pairs bound across two atomically thin layered semiconductors - have emerged as attractive platforms to study exciton condensation1-4, single-photon emission and other quantum information applications5-7. Yet, despite extensive optical spectroscopic investigations8-12, critical information about their size, valley configuration and the influence of the moiré potential remains unknown. Here, in a WSe2/MoS2 heterostructure, we captured images of the time-resolved and momentum-resolved distribution of both of the particles that bind to form the ILX: the electron and the hole. We thereby obtain a direct measurement of both the ILX diameter of around 5.2 nm, comparable with the moiré-unit-cell length of 6.1 nm, and the localization of its centre of mass. Surprisingly, this large ILX is found pinned to a region of only 1.8 nm diameter within the moiré cell, smaller than the size of the exciton itself. This high degree of localization of the ILX is backed by Bethe-Salpeter equation calculations and demonstrates that the ILX can be localized within small moiré unit cells. Unlike large moiré cells, these are uniform over large regions, allowing the formation of extended arrays of localized excitations for quantum technology.

20.
J Diabetes Sci Technol ; 16(2): 415-427, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-33124449

RESUMEN

BACKGROUND: Artificial intelligence-based technology systems offer an alternative solution for diabetic retinopathy (DR) screening compared with standard, in-office dilated eye examinations. We performed a cost-effectiveness analysis of Automated Retinal Image Analysis System (ARIAS)-based DR screening in a primary care medicine clinic that serves a low-income patient population. METHODS: A model-based, cost-effectiveness analysis of two DR screening systems was created utilizing data from a recent study comparing adherence rates to follow-up eye care among adults ages 18 or older with a clinical diagnosis of diabetes. In the study, the patients were prescreened with an ARIAS-based, nonmydriatic (undilated), point-of-care tool in the primary care setting and were compared with patients with diabetes who were referred for dilated retinal screening without prescreening, as is the current standard of care. Using a Markov model with microsimulation resulting in a total of 600 000 simulated patient experiences, we calculated the incremental cost-utility ratio (ICUR) of the two screening approaches, with regard to five-year cost-effectiveness of DR screening and treatment of vision-threatening DR. RESULTS: At five years, ARIAS-based screening showed similar utility as the standard of care screening systems. However, ARIAS reduced costs by 23.3%, with an ICUR of $258 721.81 comparing the current practice to ARIAS. CONCLUSIONS: Primary care-based ARIAS DR screening is cost-effective when compared with standard of care screening methods.


Asunto(s)
Diabetes Mellitus , Retinopatía Diabética , Adolescente , Adulto , Inteligencia Artificial , Análisis Costo-Beneficio , Retinopatía Diabética/diagnóstico , Humanos , Tamizaje Masivo/métodos , Atención Primaria de Salud
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