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1.
Proc Natl Acad Sci U S A ; 121(29): e2405231121, 2024 Jul 16.
Artículo en Inglés | MEDLINE | ID: mdl-38990952

RESUMEN

We report that ~1.8% of all mesothelioma patients and 4.9% of those younger than 55, carry rare germline variants of the BRCA1 associated RING domain 1 (BARD1) gene that were predicted to be damaging by computational analyses. We conducted functional assays, essential for accurate interpretation of missense variants, in primary fibroblasts that we established in tissue culture from a patient carrying the heterozygous BARD1V523A mutation. We found that these cells had genomic instability, reduced DNA repair, and impaired apoptosis. Investigating the underlying signaling pathways, we found that BARD1 forms a trimeric protein complex with p53 and SERCA2 that regulates calcium signaling and apoptosis. We validated these findings in BARD1-silenced primary human mesothelial cells exposed to asbestos. Our study elucidated mechanisms of BARD1 activity and revealed that heterozygous germline BARD1 mutations favor the development of mesothelioma and increase the susceptibility to asbestos carcinogenesis. These mesotheliomas are significantly less aggressive compared to mesotheliomas in asbestos workers.


Asunto(s)
Señalización del Calcio , Reparación del ADN , Predisposición Genética a la Enfermedad , Mutación de Línea Germinal , Mesotelioma , Proteínas Supresoras de Tumor , Ubiquitina-Proteína Ligasas , Humanos , Reparación del ADN/genética , Proteínas Supresoras de Tumor/genética , Proteínas Supresoras de Tumor/metabolismo , Ubiquitina-Proteína Ligasas/genética , Ubiquitina-Proteína Ligasas/metabolismo , Mesotelioma/genética , Señalización del Calcio/genética , Femenino , Masculino , Persona de Mediana Edad , Proteína p53 Supresora de Tumor/genética , Proteína p53 Supresora de Tumor/metabolismo , Apoptosis/genética , Fibroblastos/metabolismo , Amianto/toxicidad , Inestabilidad Genómica
2.
Proc Natl Acad Sci U S A ; 120(39): e2307999120, 2023 09 26.
Artículo en Inglés | MEDLINE | ID: mdl-37729199

RESUMEN

Asbestos is the main cause of malignant mesothelioma. Previous studies have linked asbestos-induced mesothelioma to the release of HMGB1 from the nucleus to the cytoplasm, and from the cytoplasm to the extracellular space. In the cytoplasm, HMGB1 induces autophagy impairing asbestos-induced cell death. Extracellularly, HMGB1 stimulates the secretion of TNFα. Jointly, these two cytokines kick-start a chronic inflammatory process that over time promotes mesothelioma development. Whether the main source of extracellular HMGB1 were the mesothelial cells, the inflammatory cells, or both was unsolved. This information is critical to identify the targets and design preventive/therapeutic strategies to interfere with asbestos-induced mesothelioma. To address this issue, we developed the conditional mesothelial HMGB1-knockout (Hmgb1ΔpMeso) and the conditional myelomonocytic-lineage HMGB1-knockout (Hmgb1ΔMylc) mouse models. We establish here that HMGB1 is mainly produced and released by the mesothelial cells during the early phases of inflammation following asbestos exposure. The release of HMGB1 from mesothelial cells leads to atypical mesothelial hyperplasia, and in some animals, this evolves over the years into mesothelioma. We found that Hmgb1ΔpMeso, whose mesothelial cells cannot produce HMGB1, show a greatly reduced inflammatory response to asbestos, and their mesothelial cells express and secrete significantly reduced levels of TNFα. Moreover, the tissue microenvironment in areas of asbestos deposits displays an increased fraction of M1-polarized macrophages compared to M2 macrophages. Supporting the biological significance of these findings, Hmgb1ΔpMeso mice showed a delayed and reduced incidence of mesothelioma and an increased mesothelioma-specific survival. Altogether, our study provides a biological explanation for HMGB1 as a driver of asbestos-induced mesothelioma.


Asunto(s)
Amianto , Proteína HMGB1 , Mesotelioma Maligno , Mesotelioma , Animales , Ratones , Factor de Necrosis Tumoral alfa/genética , Proteína HMGB1/genética , Mesotelioma/inducido químicamente , Mesotelioma/genética , Amianto/toxicidad , Inflamación , Microambiente Tumoral
3.
Proc Natl Acad Sci U S A ; 120(4): e2217840120, 2023 01 24.
Artículo en Inglés | MEDLINE | ID: mdl-36656861

RESUMEN

BAP1 is a powerful tumor suppressor gene characterized by haplo insufficiency. Individuals carrying germline BAP1 mutations often develop mesothelioma, an aggressive malignancy of the serosal layers covering the lungs, pericardium, and abdominal cavity. Intriguingly, mesotheliomas developing in carriers of germline BAP1 mutations are less aggressive, and these patients have significantly improved survival. We investigated the apparent paradox of a tumor suppressor gene that, when mutated, causes less aggressive mesotheliomas. We discovered that mesothelioma biopsies with biallelic BAP1 mutations showed loss of nuclear HIF-1α staining. We demonstrated that during hypoxia, BAP1 binds, deubiquitylates, and stabilizes HIF-1α, the master regulator of the hypoxia response and tumor cell invasion. Moreover, primary cells from individuals carrying germline BAP1 mutations and primary cells in which BAP1 was silenced using siRNA had reduced HIF-1α protein levels in hypoxia. Computational modeling and co-immunoprecipitation experiments revealed that mutations of BAP1 residues I675, F678, I679, and L691 -encompassing the C-terminal domain-nuclear localization signal- to A, abolished the interaction with HIF-1α. We found that BAP1 binds to the N-terminal region of HIF-1α, where HIF-1α binds DNA and dimerizes with HIF-1ß forming the heterodimeric transactivating complex HIF. Our data identify BAP1 as a key positive regulator of HIF-1α in hypoxia. We propose that the significant reduction of HIF-1α activity in mesothelioma cells carrying biallelic BAP1 mutations, accompanied by the significant reduction of HIF-1α activity in hypoxic tissues containing germline BAP1 mutations, contributes to the reduced aggressiveness and improved survival of mesotheliomas developing in carriers of germline BAP1 mutations.


Asunto(s)
Subunidad alfa del Factor 1 Inducible por Hipoxia , Mesotelioma Maligno , Mesotelioma , Ubiquitina Tiolesterasa , Humanos , Heterocigoto , Subunidad alfa del Factor 1 Inducible por Hipoxia/genética , Mesotelioma/genética , Mesotelioma/metabolismo , Mesotelioma Maligno/genética , Mesotelioma Maligno/complicaciones , Mutación , Proteínas Supresoras de Tumor/metabolismo , Ubiquitina Tiolesterasa/metabolismo
4.
Clin Gastroenterol Hepatol ; 22(6): 1286-1294.e4, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38216022

RESUMEN

BACKGROUND & AIMS: Traditional risk factors for serious infections with advanced therapies in patients with Crohn's disease (CD) have been assessed at baseline before starting therapy. We evaluated the impact of treatment response on the risk of serious infections in adalimumab-treated patients with CD through secondary analysis of the PYRAMID registry (NCT00524537). METHODS: We included patients with CD who initiated adalimumab and classified them as treatment responders (achieved steroid-free clinical remission based on patient-reported outcomes) vs nonresponders (not in steroid-free clinical remission) at 6 months after treatment initiation (landmark). We compared the risk of serious infections between responders vs nonresponders between 6 and 36 months after treatment initiation through stabilized inverse probability of treatment weighting Cox proportional hazards model. RESULTS: Of 1515 adalimumab-treated patients, 763 (50.4%) were classified as responders at 6 months (37 ± 13 y; 56% female; disease duration, 9.5 ± 8.5 y). Compared with nonresponders, responders were less likely to have moderate to severe symptoms (55.6% vs 33%), or require steroids (45.5% vs 17.3%) or opiates (6.6% vs 1.3%) at baseline, without any differences in disease location, perianal disease, and prior CD complications. During follow-up evaluation, using stabilized inverse probability of treatment weighting, responders were 34% less likely to experience serious infections compared with nonresponders (hazard ratio, 0.66; 95% CI, 0.46-0.96). Risk of gastrointestinal and extraintestinal infections was lower in responders vs nonresponders. CONCLUSIONS: Patients with CD who respond to adalimumab have a lower risk of developing serious infections compared with nonresponders. These findings underscore that initiation of advanced therapy for CD may lower the risk of serious infections through effective disease control and avoidance of corticosteroids.


Asunto(s)
Adalimumab , Enfermedad de Crohn , Sistema de Registros , Humanos , Enfermedad de Crohn/tratamiento farmacológico , Enfermedad de Crohn/complicaciones , Masculino , Femenino , Adulto , Adalimumab/uso terapéutico , Persona de Mediana Edad , Resultado del Tratamiento , Infecciones/epidemiología , Medición de Riesgo , Adulto Joven , Factores de Riesgo , Antiinflamatorios/uso terapéutico
5.
Proc Natl Acad Sci U S A ; 118(48)2021 11 30.
Artículo en Inglés | MEDLINE | ID: mdl-34815344

RESUMEN

Carriers of heterozygous germline BAP1 mutations (BAP1+/-) are affected by the "BAP1 cancer syndrome." Although they can develop almost any cancer type, they are unusually susceptible to asbestos carcinogenesis and mesothelioma. Here we investigate why among all carcinogens, BAP1 mutations cooperate with asbestos. Asbestos carcinogenesis and mesothelioma have been linked to a chronic inflammatory process promoted by the extracellular release of the high-mobility group box 1 protein (HMGB1). We report that BAP1+/- cells secrete increased amounts of HMGB1, and that BAP1+/- carriers have detectable serum levels of acetylated HMGB1 that further increase when they develop mesothelioma. We linked these findings to our discovery that BAP1 forms a trimeric protein complex with HMGB1 and with histone deacetylase 1 (HDAC1) that modulates HMGB1 acetylation and its release. Reduced BAP1 levels caused increased ubiquitylation and degradation of HDAC1, leading to increased acetylation of HMGB1 and its active secretion that in turn promoted mesothelial cell transformation.


Asunto(s)
Amianto , Proteína HMGB1/química , Histona Desacetilasa 1/química , Proteínas Supresoras de Tumor/química , Ubiquitina Tiolesterasa/química , Animales , Biomarcadores de Tumor/metabolismo , Carcinogénesis , Núcleo Celular/metabolismo , Femenino , Interacción Gen-Ambiente , Mutación de Línea Germinal , Proteína HMGB1/genética , Heterocigoto , Histona Desacetilasa 1/genética , Incidencia , Inflamación , Masculino , Mesotelioma/metabolismo , Ratones , Mutación , Pronóstico , Unión Proteica , Proteínas Supresoras de Tumor/metabolismo , Ubiquitina/química , Ubiquitina Tiolesterasa/metabolismo
6.
Alzheimers Dement ; 2024 Jun 21.
Artículo en Inglés | MEDLINE | ID: mdl-39030734

RESUMEN

INTRODUCTION: Bumetanide, a loop diuretic, was identified as a candidate drug for repurposing for Alzheimer's disease (AD) based on its effects on transcriptomic apolipoprotein E signatures. Cross-sectional analyses of electronic health records suggest that bumetanide is associated with decreased prevalence of AD; however, temporality between bumetanide exposure and AD development has not been established. METHODS: We evaluated Medicare claims data using Cox proportional hazards regression to evaluate the association between time-dependent use of bumetanide and time to first AD diagnosis while controlling for patient characteristics. Multiple sensitivity analyses were conducted to test the robustness of the findings. RESULTS: We sampled 833,561 Medicare beneficiaries, 60.8% female, with mean (standard deviation) age of 70.4 (12). Bumetanide use was not significantly associated with AD risk (hazard ratio 1.05; 95% confidence interval, 0.99-1.10). DISCUSSION: Using a nationwide dataset and a retrospective cohort study design, we were not able to identify a time-dependent effect of bumetanide lowering AD risk. HIGHLIGHTS: Bumetanide was identified as a candidate for repurposing for Alzheimer's disease (AD). We evaluated the association between bumetanide use and risk of AD. We used Medicare data and accounted for duration of bumetanide use. Bumetanide use was not significantly associated with risk of AD.

7.
Stat Med ; 2023 Jan 03.
Artículo en Inglés | MEDLINE | ID: mdl-36597179

RESUMEN

We consider the conditional treatment effect for competing risks data in observational studies. We derive the efficient score for the treatment effect using modern semiparametric theory, as well as two doubly robust scores with respect to (1) the assumed propensity score for treatment and the censoring model, and (2) the outcome models for the competing risks. An important property regarding the estimators is rate double robustness, in addition to the classical model double robustness. Rate double robustness enables the use of machine learning and nonparametric methods in order to estimate the nuisance parameters, while preserving the root- n $$ n $$ asymptotic normality of the estimated treatment effect for inferential purposes. We study the performance of the estimators using simulation. The estimators are applied to the data from a cohort of Japanese men in Hawaii followed since 1960s in order to study the effect of mid-life drinking behavior on late life cognitive outcomes. The approaches developed in this article are implemented in the R package "HazardDiff".

8.
Stat Med ; 42(3): 228-245, 2023 02 10.
Artículo en Inglés | MEDLINE | ID: mdl-36415044

RESUMEN

Explained variation is well understood under linear regression models and has been extended to models for survival data. In this article, we consider the mixture cure models. We propose two approaches to define explained variation under the mixture cure models, one based on the Kullback-Leibler information gain and the other based on residual sum of squares. We show that the proposed measures have desired properties as measures of explained variation, similar to those under other regression models. A simulation study is conducted to demonstrate the properties of the proposed measures. They are also applied to real data analyses to illustrate the use of explained variation.


Asunto(s)
Modelos Estadísticos , Humanos , Modelos de Riesgos Proporcionales , Simulación por Computador , Modelos Lineales , Análisis de Supervivencia
9.
Proc Natl Acad Sci U S A ; 117(41): 25543-25552, 2020 10 13.
Artículo en Inglés | MEDLINE | ID: mdl-32999071

RESUMEN

Asbestos causes malignant transformation of primary human mesothelial cells (HM), leading to mesothelioma. The mechanisms of asbestos carcinogenesis remain enigmatic, as exposure to asbestos induces HM death. However, some asbestos-exposed HM escape cell death, accumulate DNA damage, and may become transformed. We previously demonstrated that, upon asbestos exposure, HM and reactive macrophages releases the high mobility group box 1 (HMGB1) protein that becomes detectable in the tissues near asbestos deposits where HMGB1 triggers chronic inflammation. HMGB1 is also detectable in the sera of asbestos-exposed individuals and mice. Searching for additional biomarkers, we found higher levels of the autophagy marker ATG5 in sera from asbestos-exposed individuals compared to unexposed controls. As we investigated the mechanisms underlying this finding, we discovered that the release of HMGB1 upon asbestos exposure promoted autophagy, allowing a higher fraction of HM to survive asbestos exposure. HMGB1 silencing inhibited autophagy and increased asbestos-induced HM death, thereby decreasing asbestos-induced HM transformation. We demonstrate that autophagy was induced by the cytoplasmic and extracellular fractions of HMGB1 via the engagement of the RAGE receptor and Beclin 1 pathway, while nuclear HMGB1 did not participate in this process. We validated our findings in a novel unique mesothelial conditional HMGB1-knockout (HMGB1-cKO) mouse model. Compared to HMGB1 wild-type mice, mesothelial cells from HMGB1-cKO mice showed significantly reduced autophagy and increased cell death. Autophagy inhibitors chloroquine and desmethylclomipramine increased cell death and reduced asbestos-driven foci formation. In summary, HMGB1 released upon asbestos exposure induces autophagy, promoting HM survival and malignant transformation.


Asunto(s)
Amianto/efectos adversos , Autofagia/efectos de los fármacos , Transformación Celular Neoplásica/inducido químicamente , Proteína HMGB1/metabolismo , Mesotelioma/metabolismo , Adulto , Anciano , Animales , Células Cultivadas , Células Epiteliales/citología , Células Epiteliales/metabolismo , Humanos , Masculino , Ratones , Ratones Noqueados , Persona de Mediana Edad , Exposición Profesional
10.
Proc Natl Acad Sci U S A ; 117(52): 33466-33473, 2020 12 29.
Artículo en Inglés | MEDLINE | ID: mdl-33318203

RESUMEN

Rare biallelic BLM gene mutations cause Bloom syndrome. Whether BLM heterozygous germline mutations (BLM+/-) cause human cancer remains unclear. We sequenced the germline DNA of 155 mesothelioma patients (33 familial and 122 sporadic). We found 2 deleterious germline BLM+/- mutations within 2 of 33 families with multiple cases of mesothelioma, one from Turkey (c.569_570del; p.R191Kfs*4) and one from the United States (c.968A>G; p.K323R). Some of the relatives who inherited these mutations developed mesothelioma, while none with nonmutated BLM were affected. Furthermore, among 122 patients with sporadic mesothelioma treated at the US National Cancer Institute, 5 carried pathogenic germline BLM+/- mutations. Therefore, 7 of 155 apparently unrelated mesothelioma patients carried BLM+/- mutations, significantly higher (P = 6.7E-10) than the expected frequency in a general, unrelated population from the gnomAD database, and 2 of 7 carried the same missense pathogenic mutation c.968A>G (P = 0.0017 given a 0.00039 allele frequency). Experiments in primary mesothelial cells from Blm+/- mice and in primary human mesothelial cells in which we silenced BLM revealed that reduced BLM levels promote genomic instability while protecting from cell death and promoted TNF-α release. Blm+/- mice injected intraperitoneally with asbestos had higher levels of proinflammatory M1 macrophages and of TNF-α, IL-1ß, IL-3, IL-10, and IL-12 in the peritoneal lavage, findings linked to asbestos carcinogenesis. Blm+/- mice exposed to asbestos had a significantly shorter survival and higher incidence of mesothelioma compared to controls. We propose that germline BLM+/- mutations increase the susceptibility to asbestos carcinogenesis, enhancing the risk of developing mesothelioma.


Asunto(s)
Asbestosis/genética , Predisposición Genética a la Enfermedad , Mutación de Línea Germinal/genética , Mesotelioma/genética , RecQ Helicasas/genética , Adulto , Anciano , Animales , Asbesto Crocidolita , Familia , Femenino , Inestabilidad Genómica , Heterocigoto , Humanos , Incidencia , Inflamación/patología , Masculino , Ratones , Persona de Mediana Edad
11.
Clin Gastroenterol Hepatol ; 20(1): 126-135, 2022 01.
Artículo en Inglés | MEDLINE | ID: mdl-33039584

RESUMEN

BACKGROUND & AIMS: We aimed to compare safety and effectiveness of vedolizumab to tumor necrosis factor (TNF)-antagonist therapy in ulcerative colitis in routine practice. METHODS: A multicenter, retrospective, observational cohort study (May 2014 to December 2017) of ulcerative colitis patients treated with vedolizumab or TNF-antagonist therapy. Propensity score weighted comparisons for development of serious adverse events and achievement of clinical remission, steroid-free clinical remission, and steroid-free deep remission. A priori determined subgroup comparisons in TNF-antagonist-naïve and -exposed patients, and for vedolizumab against infliximab and subcutaneous TNF-antagonists separately. RESULTS: A total of 722 (454 vedolizumab, 268 TNF antagonist) patients were included. Vedolizumab-treated patients were more likely to achieve clinical remission (hazard ratio [HR], 1.651; 95% confidence interval [CI], 1.229-2.217), steroid-free clinical remission (HR, 1.828; 95% CI, 1.135-2.944), and steroid-free deep remission (HR, 2.819; 95% CI, 1.496-5.310) than those treated with TNF antagonists. Results were consistent across subgroup analyses in TNF-antagonist-naïve and -exposed patients, and for vedolizumab vs infliximab and vs subcutaneous TNF-antagonist agents separately. Overall, there were no statistically significant differences in the risk of serious adverse events (HR, 0.899; 95% CI, 0.502-1.612) or serious infections (HR, 1.235; 95% CI, 0.608-2.511) between vedolizumab-treated and TNF-antagonist-treated patients. However, in TNF-antagonist-naïve patients, vedolizumab was less likely to be associated with serious adverse events than TNF antagonists (HR, 0.192; 95% CI, 0.049-0.754). CONCLUSIONS: Treatment of ulcerative colitis with vedolizumab is associated with higher rates of remission than treatment with TNF-antagonist therapy in routine practice, and lower rates of serious adverse events in TNF-antagonist-naïve patients.


Asunto(s)
Colitis Ulcerosa , Inhibidores del Factor de Necrosis Tumoral , Anticuerpos Monoclonales Humanizados , Colitis Ulcerosa/tratamiento farmacológico , Colitis Ulcerosa/patología , Fármacos Gastrointestinales/efectos adversos , Humanos , Estudios Retrospectivos , Resultado del Tratamiento , Inhibidores del Factor de Necrosis Tumoral/efectos adversos , Inhibidores del Factor de Necrosis Tumoral/uso terapéutico , Factor de Necrosis Tumoral alfa
12.
Pediatr Crit Care Med ; 23(4): 277-285, 2022 04 01.
Artículo en Inglés | MEDLINE | ID: mdl-35180199

RESUMEN

OBJECTIVES: To determine the frequency and characteristics of complications of peripherally administered hypertonic saline (HTS) through assessment of infiltration and extravasation. DESIGN: Retrospective cross-sectional study. SETTING: Freestanding tertiary care pediatric hospital. PATIENTS: Children who received HTS through a peripheral IV catheter (PIVC). INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: We conducted a single-center retrospective review from January 2012 to 2019. A total of 526 patients with 1,020 unique administrations of HTS through a PIVC met inclusion criteria. The primary endpoint was PIVC failure due to infiltration or extravasation. The indication for the administration of HTS infusion was collected. Catheter data was captured, including the setting of catheter placement, anatomical location on the patient, gauge size, length of time from catheter insertion to HTS infusion, in situ duration of catheter lifespan, and removal rationale. The administration data for HTS was reviewed and included volume of administration, bolus versus continuous infusion, infusion rate, infusion duration, and vesicant medications administered through the PIVC. There were 843 bolus infusions of HTS and 172 continuous infusions. Of the bolus administrations, there were eight infiltrations (0.9%). The continuous infusion group had 13 infiltrations (7.6%). There were no extravasations in either group, and no patients required medical therapy or intervention by the wound care or plastic surgery teams. There was no significant morbidity attributed to HTS administration in either group. CONCLUSIONS: HTS administered through a PIVC infrequently infiltrates in critically ill pediatric patients. The infiltration rate was low when HTS is administered as a bolus but higher when given as a continuous infusion. However, no patient suffered an extravasation injury or long-term morbidity from any infiltration.


Asunto(s)
Enfermedad Crítica , Unidades de Cuidado Intensivo Pediátrico , Niño , Enfermedad Crítica/terapia , Estudios Transversales , Humanos , Estudios Retrospectivos , Solución Salina Hipertónica
13.
Sensors (Basel) ; 22(22)2022 Nov 17.
Artículo en Inglés | MEDLINE | ID: mdl-36433491

RESUMEN

In this research, we proposed and experimentally verified a compact all-fiber sensor that can measure refractive index (RI) and temperature simultaneously. Two segments of hollow-core fiber (HCF) are connected to the two ends of the four-core fiber (FCF) as a beam splitter and a coupler, and then spliced with two sections of single-mode fibers (lead-in and lead-out SMF), respectively. The two hollow-core fibers can excite the higher-order modes of the four-core fiber and recouple the core modes and higher-order modes into the outgoing single-mode fiber, thereby forming inter-mode interference. The different response sensitivities of two interference dips to RI and temperature manifest that the proposed structure can achieve simultaneous measurement. From the experimental results, it can be seen that the maximum sensitivity of the sensor to RI and temperature is 275.30 nm/RIU and 94.4 pm/°C, respectively. When the wavelength resolution is 0.02 nm, the RI and temperature resolutions of the sensor are 7.74 × 10-5 RIU and 0.335 °C. The proposed dual-parameter optical sensor has the advantages of high sensitivities, good repeatability, simple fabrication, and structure. In addition, it has potential application value in multi-parameter simultaneous measurement.

14.
Opt Express ; 29(13): 21020-21030, 2021 Jun 21.
Artículo en Inglés | MEDLINE | ID: mdl-34266177

RESUMEN

The chiroptical response of the chiral metasurface can be characterized by circular dichroism, which is defined as the absorption difference between left-handed circularly polarized incidence and right-handed circularly incidence. It can be applied in biology, chemistry, optoelectronics, etc. Here, we propose a dynamically tunable chiral metasurface structure, which is composed of two metal split-ring resonators and a graphene layer embedded in dielectric. The structure reflects right-handed circularly polarized waves and absorbs left-handed circularly polarized waves under normal incidence. The overall unit structural parameters of the chiral metasurface were discussed and analyzed, and the circular dichroism was 0.85 at 1.181 THz. Additionally, the digital imaging function can be realized based on the chiral metasurface structure, and the resolution of terahertz digital imaging can be dynamically tuned by changing the Fermi level of graphene. The proposed structure has potential applications in realizing tunable dynamic imaging and other communication fields.

15.
Opt Express ; 29(16): 25894-25902, 2021 Aug 02.
Artículo en Inglés | MEDLINE | ID: mdl-34614908

RESUMEN

Plasmonic metallic nanostructures with anisotropic design have unusual polarization-selective characteristic which can be utilized to build nanopolarizers at the nanoscale. Herein, we propose a dual-color image display platform by reconfiguring two types of silver nanoblocks in a single-celled metasurface. Governed by Malus's law, the two types of silver nanoblocks both acting as nanopolarizers with different orientations can continuously modulate the intensity of incident linearly polarized red and green light pixel-by-pixel, respectively. As a result, an ultra-compact, high-resolution, and continuous-greyscale dual-color image can be recorded right at the surface of the meta-device. We demonstrate the dual-color Malus metasurface by successfully encoding and decoding a red-green continuously-grayscale image into a metasurface sample. The experimentally captured meta-image with high-fidelity and resolution as high as 63500 dots per inch (dpi) has verified our proposal. With the advantages such as continuous grayscale modulation, ultrathin, high stability and high density, the proposed dual-color encoded metasurfaces can be readily used in ultra-compact image displays, high-end anti-counterfeiting, high-density optical information storage and information encryption, etc.

16.
Stat Med ; 40(1): 85-100, 2021 01 15.
Artículo en Inglés | MEDLINE | ID: mdl-33000531

RESUMEN

We study explained variation under the additive hazards regression model for right-censored data. We consider different approaches for developing such a measure, and focus on one that estimates the proportion of variation in the failure time explained by the covariates. We study the properties of the measure both analytically, and through extensive simulations. We apply the measure to a well-known survival dataset as well as the linked surveillance, epidemiology, and end results-Medicare database for prediction of mortality in early stage prostate cancer patients using high-dimensional claims codes.


Asunto(s)
Medicare , Neoplasias de la Próstata , Anciano , Humanos , Masculino , Modelos de Riesgos Proporcionales , Neoplasias de la Próstata/epidemiología , Análisis de Supervivencia , Estados Unidos/epidemiología
17.
Am J Perinatol ; 38(2): 131-139, 2021 01.
Artículo en Inglés | MEDLINE | ID: mdl-31430819

RESUMEN

OBJECTIVE: The study compares the short-term outcomes of late preterm infants (LPI) at an academic center in San Diego, California after a change in protocol that eliminated a previously mandatory 12-hour neonatal intensive care unit (NICU) observation period after birth. STUDY DESIGN: This is a retrospective observational study examining all LPI born with gestational age 35 to 366/7 weeks between October 1, 2016 and October 31, 2017. A total of 189 infants were included in the review. Short-term outcomes were analyzed before and after the protocol change. RESULTS: Transfers to the NICU from family-centered care (FCC) were considerably higher (23.2%) following the protocol change, compared to before (8.2%). More infants were transferred to the NICU for failed car seat tests postprotocol compared to preprotocol. Length of stay before the protocol change was 5.13 days compared to 4.80 days after. CONCLUSION: LPI are vulnerable to morbidities after delivery and through discharge. We found an increase in failed car seat tests in LPI cared for in FCC after elimination of a mandatory NICU observation after birth. The transitions of care from delivery to discharge are key checkpoints in minimizing complications.


Asunto(s)
Recien Nacido Prematuro , Unidades de Cuidado Intensivo Neonatal , Atención Dirigida al Paciente , Nacimiento Prematuro/epidemiología , Adulto , Sistemas de Retención Infantil , Femenino , Edad Gestacional , Humanos , Recién Nacido , Enfermedades del Prematuro/epidemiología , Tiempo de Internación , Masculino , Embarazo , Estudios Retrospectivos , Triaje/normas
18.
Clin Gastroenterol Hepatol ; 18(2): 424-431.e7, 2020 02.
Artículo en Inglés | MEDLINE | ID: mdl-31108227

RESUMEN

BACKGROUND & AIMS: With several options available for patients with moderate-severe ulcerative colitis (UC), rapidity of symptom resolution could be an important differentiator. We compared the efficacy and speed of onset of action of infliximab vs golimumab induction therapy using patient-level data from phase 3 trials (ACT-1, ACT-2, and PURSUIT-SC). METHODS: We compared differences in proportions of patients who achieved the composite outcome of a rectal bleeding score=0 and stool frequency score ≤1 (patient-reported outcome 2 remission) at weeks 2 and 6 of treatment with standard-dose infliximab vs golimumab using logistic generalized estimating equation. Overall efficacy for inducing clinical remission (Mayo clinic score <3) was compared using logistic regression. Analyses were adjusted for sex, disease extent, baseline clinical and endoscopic severity, C-reactive protein, albumin, body weight and concomitant medications (immunomosuppressives, corticosteroids, and 5-aminsalicylates). RESULTS: Trial populations were similar and no differences were observed among the placebo groups in the studies. A significantly higher proportion patients treated with infliximab than golimumab achieved patient-reported outcome 2 remission at week 2 (35% vs 30%; adjusted odds ratio [OR], 1.71; 95% CI, 1.15-2.55) and at week 6 (50.0% vs 38.9%; adjusted OR, 2.0; 95% CI, 1.40-2.94). Infliximab-treated patients were also significantly more likely to achieve clinical remission than golimumab-treated patients (adjusted OR, 3.01; 95% CI, 1.95-4.70), with consistent findings in patients with moderate or severe UC. CONCLUSIONS: Based on a patient-level analysis of data from phase 3 trials, infliximab resolves symptoms more rapidly and has greater efficacy for inducing remission than golimumab in patients with moderate-to-severe UC.


Asunto(s)
Colitis Ulcerosa , Anticuerpos Monoclonales/uso terapéutico , Colitis Ulcerosa/tratamiento farmacológico , Humanos , Infliximab , Inducción de Remisión , Resultado del Tratamiento , Factor de Necrosis Tumoral alfa
19.
Rheumatology (Oxford) ; 59(6): 1262-1271, 2020 06 01.
Artículo en Inglés | MEDLINE | ID: mdl-31566229

RESUMEN

OBJECTIVE: To evaluate the associations between oral corticosteroid (OCS) dose early and late in pregnancy and preterm birth (PTB) among women with RA. METHODS: Pregnant women in the MotherToBaby Pregnancy Studies (2003-2014) with RA (n = 528) were included in the primary analysis. Information was collected by phone interview and from medical records. We estimated risk ratios (RR) for OCS dose trajectories and other disease-related medications before gestational day 140 and hazard ratios (HR) for time-varying exposures after gestational day 139. RESULTS: PTB risk was 15.5% overall. Compared with no OCS, PTB risk was increased in high (adjusted (a)RR: 4.77 (95% CI: 2.76, 8.26)) and medium (aRR: 1.81 (95% CI: 1.10, 2.97)) cumulative OCS dose trajectories during the first 139 gestational days. The low cumulative trajectory group was associated with an increased risk of PTB that was not statistically significant (aRR: 1.38 (95% CI: 0.79, 2.38)), and DMARDs were not associated with PTB (biologic DMARDs aHR: 1.08 (95% CI: 0.70, 1.66); non-biologic DMARDs aHR: 0.87 (95% CI: 0.55, 1.38)). OCS exposure to ⩾10 mg of prednisone equivalent daily dose after gestational day 139 vs none was associated with increased PTB rate (aHR: 2.45 (95% CI: 1.32, 4.56)), whereas <10 mg was associated with a modestly increased rate of PTB that was not statistically significant (aHR: 1.18 (95% CI: 0.60, 2.30)). CONCLUSION: Higher OCS doses vs no OCS use, both earlier and later in pregnancy, were associated with an increase in PTB among women with RA.


Asunto(s)
Corticoesteroides/efectos adversos , Asma/tratamiento farmacológico , Enfermedades Autoinmunes/tratamiento farmacológico , Nacimiento Prematuro/inducido químicamente , Administración Oral , Adulto , Femenino , Humanos , Recién Nacido , Embarazo , Factores de Riesgo
20.
Opt Express ; 28(1): 216-225, 2020 Jan 06.
Artículo en Inglés | MEDLINE | ID: mdl-32118952

RESUMEN

Recent studies have shown that quadratic-power-exponent-phase (QPEP) vortex and modified QPEP vortex have some novel properties and potential applications in optical manipulation, orbital angular momentum (OAM) communication, OAM multicasting and so on. In these applications, there may be potential need of processing these kinds of beams by using uniaxial crystals. In this paper, the analytical propagation equations of Gaussian QPEP vortex and modified QPEP vortex propagating in uniaxial crystals are derived and the evolution of the angular momentum via spin-orbital coupling during the propagation is investigated. This may be meaningful for guiding and promoting the applications of the QPEP vortex and modified QPEP vortex.

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