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1.
Dermatol Ther (Heidelb) ; 12(9): 2077-2085, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35933552

RESUMO

INTRODUCTION: Multiple clinical trials showed that 12 weeks of abrocitinib monotherapy was safe and effective for the treatment of moderate-to-severe atopic dermatitis (AD). The reversibility of pharmacologic activity after abrocitinib discontinuation was not described. METHODS: This post hoc analysis used data from a phase 2b study to evaluate maintenance of disease control during a 4-week drug-free follow-up period in patients with moderate-to-severe AD treated with once-daily abrocitinib (200 mg/100 mg) or placebo for 12 weeks. Proportions of patients who achieved and maintained 50% or 75% improvement in Eczema Area and Severity Index (EASI-50/EASI-75), an Investigator's Global Assessment (IGA) score of 0/1, or at least a 4-point improvement in the pruritus numeric rating scale (pruritus NRS4) were determined. Biomarkers of Janus kinase inhibition and AD disease were measured in blood samples. RESULTS: Among week 12 responders to abrocitinib 200 mg, 77.4%, 42.3%, 21.1%, and 42.9% maintained their EASI-50, EASI-75, IGA, and pruritus NRS4 response at week 16; corresponding proportions of week 12 responders maintaining response to abrocitinib 100 mg were 51.9%, 35.0%, 33.3%, and 43.5%, respectively. Four weeks after abrocitinib discontinuation, all AD biomarkers reverted toward baseline levels, with high-sensitivity C-reactive protein and eosinophil percentage demonstrating the most complete recovery in patients treated with abrocitinib versus placebo. CONCLUSION: Abrocitinib discontinuation resulted in rapid reversal of disease control consistent with reversal of suppression of pharmacodynamic and AD-specific biomarkers during the drug-free follow-up period. Maintenance of response was inversely related to the threshold of improvement. Patients with moderate-to-severe AD using continuous abrocitinib therapy would likely have the best long-term outcomes. TRIAL REGISTRATION: ClinicalTrials.gov identifier NCT02780167.

2.
Ann Biomed Eng ; 47(1): 22-38, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30306381

RESUMO

Magnetic resonance within the field of wireless power transfer has seen an increase in popularity over the past decades. This rise can be attributed to the technological advances of electronics and the increased efficiency of popular battery technologies. The same principles of electromagnetic theory can be applied to the medical field. Several medical devices intended for use inside the body use batteries and electrical circuits that could be powered wirelessly. Other medical devices limit the mobility or make patients uncomfortable while in use. The fundamental theory of electromagnetics can improve the field by solving some of these problems. This survey paper summarizes the recent uses and discoveries of wireless power in the medical field. A comprehensive search for papers was conducted using engineering search engines and included papers from related conferences. During the initial search, 247 papers were found then non-relevant papers were eliminated to leave only suitable material. Seventeen relevant journal papers and/or conference papers were found, then separated into defined categories: Implants, Pumps, Ultrasound Imaging, and Gastrointestinal (GI) Endoscopy. The approach and methods for each paper were analyzed and compared yielding a comprehensive review of these state of the art technologies.


Assuntos
Desenho de Equipamento/tendências , Equipamentos e Provisões , Tecnologia sem Fio/tendências , Humanos
3.
Adv Mater ; 29(21)2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28244158

RESUMO

The world is recently witnessing an explosive development of novel electronic and optoelectronic devices that demand more-reliable power sources that combine higher energy density and longer-term durability. Supercapacitors have become one of the most promising energy-storage systems, as they present multifold advantages of high power density, fast charging-discharging, and long cyclic stability. However, the intrinsically low energy density inherent to traditional supercapacitors severely limits their widespread applications, triggering researchers to explore new types of supercapacitors with improved performance. Asymmetric supercapacitors (ASCs) assembled using two dissimilar electrode materials offer a distinct advantage of wide operational voltage window, and thereby significantly enhance the energy density. Recent progress made in the field of ASCs is critically reviewed, with the main focus on an extensive survey of the materials developed for ASC electrodes, as well as covering the progress made in the fabrication of ASC devices over the last few decades. Current challenges and a future outlook of the field of ASCs are also discussed.

4.
Nat Commun ; 7: 13319, 2016 11 11.
Artigo em Inglês | MEDLINE | ID: mdl-27834367

RESUMO

A promising energy source for many current and future applications is a ribbon-like device that could simultaneously harvest and store energy. Due to the high flexibility and weavable property, a fabric/matrix made using these ribbons could be highly beneficial for powering wearable electronics. Unlike the approach of using two separate devices, here we report a ribbon that integrates a solar cell and a supercapacitor. The electrons generated by the solar cell are directly transferred and stored on the reverse side of its electrode which in turn also functions as an electrode for the supercapacitor. When the flexible solar ribbon is illuminated with simulated solar light, the supercapacitor holds an energy density of 1.15 mWh cm-3 and a power density of 243 mW cm-3. Moreover, these ribbons are successfully woven into a fabric form. Our all-solid-state ribbon unveils a highly flexible and portable self-sufficient energy system with potential applications in wearables, drones and electric vehicles.

5.
ACS Nano ; 10(12): 10726-10735, 2016 12 27.
Artigo em Inglês | MEDLINE | ID: mdl-27732778

RESUMO

Two-dimensional (2D) transition-metal dichalcogenides (TMDs) have emerged as promising capacitive materials for supercapacitor devices owing to their intrinsically layered structure and large surface areas. Hierarchically integrating 2D TMDs with other functional nanomaterials has recently been pursued to improve electrochemical performances; however, it often suffers from limited cyclic stabilities and capacitance losses due to the poor structural integrity at the interfaces of randomly assembled materials. Here, we report high-performance core/shell nanowire supercapacitors based on an array of one-dimensional (1D) nanowires seamlessly integrated with conformal 2D TMD layers. The 1D and 2D supercapacitor components possess "one-body" geometry with atomically sharp and structurally robust core/shell interfaces, as they were spontaneously converted from identical metal current collectors via sequential oxidation/sulfurization. These hybrid supercapacitors outperform previously developed any stand-alone 2D TMD-based supercapacitors; particularly, exhibiting an exceptional charge-discharge retention over 30,000 cycles owing to their structural robustness, suggesting great potential for unconventional energy storage technologies.

6.
Small ; 11(39): 5289-95, 2015 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-26287120

RESUMO

Cable-shaped supercapacitors (SCs) have recently aroused significant attention due to their attractive properties such as small size, lightweight, and bendability. Current cable-shaped SCs have symmetric device configuration. However, if an asymmetric design is used in cable-shaped supercapacitors, they would become more attractive due to broader cell operation voltages, which results in higher energy densities. Here, a novel coil-type asymmetric supercapacitor electrical cable (CASEC) is reported with enhanced cell operation voltage and extraordinary mechanical-electrochemical stability. The CASECs show excellent charge-discharge profiles, extraordinary rate capability (95.4%), high energy density (0.85 mWh cm(-3)), remarkable flexibility and bendability, and superior bending cycle stability (≈93.0% after 4000 cycles at different bending states). In addition, the CASECs not only exhibit the capability to store energy but also to transmit electricity simultaneously and independently. The integrated electrical conduction and storage capability of CASECS offer many potential applications in solar energy storage and electronic gadgets.

7.
Int J Radiat Oncol Biol Phys ; 78(5): 1292-300, 2010 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-20932654

RESUMO

PURPOSE: To identify single nucleotide polymorphisms (SNPs) associated with erectile dysfunction (ED) among African-American prostate cancer patients treated with external beam radiation therapy. METHODS AND MATERIALS: A cohort of African-American prostate cancer patients treated with external beam radiation therapy was observed for the development of ED by use of the five-item Sexual Health Inventory for Men (SHIM) questionnaire. Final analysis included 27 cases (post-treatment SHIM score ≤7) and 52 control subjects (post-treatment SHIM score ≥16). A genome-wide association study was performed using approximately 909,000 SNPs genotyped on Affymetrix 6.0 arrays (Affymetrix, Santa Clara, CA). RESULTS: We identified SNP rs2268363, located in the follicle-stimulating hormone receptor (FSHR) gene, as significantly associated with ED after correcting for multiple comparisons (unadjusted p = 5.46 × 10(-8), Bonferroni p = 0.028). We identified four additional SNPs that tended toward a significant association with an unadjusted p value < 10(-6). Inference of population substructure showed that cases had a higher proportion of African ancestry than control subjects (77% vs. 60%, p = 0.005). A multivariate logistic regression model that incorporated estimated ancestry and four of the top-ranked SNPs was a more accurate classifier of ED than a model that included only clinical variables. CONCLUSIONS: To our knowledge, this is the first genome-wide association study to identify SNPs associated with adverse effects resulting from radiotherapy. It is important to note that the SNP that proved to be significantly associated with ED is located within a gene whose encoded product plays a role in male gonad development and function. Another key finding of this project is that the four SNPs most strongly associated with ED were specific to persons of African ancestry and would therefore not have been identified had a cohort of European ancestry been screened. This study demonstrates the feasibility of a genome-wide approach to investigate genetic predisposition to radiation injury.


Assuntos
Negro ou Afro-Americano/genética , Disfunção Erétil/genética , Estudo de Associação Genômica Ampla , Polimorfismo de Nucleotídeo Único/genética , Neoplasias da Próstata/radioterapia , Receptores do FSH/genética , Idoso , População Negra/genética , Estudos de Casos e Controles , Estudos de Coortes , Predisposição Genética para Doença/genética , Humanos , Masculino , Pessoa de Meia-Idade , Lesões por Radiação/genética , Análise de Regressão , Inquéritos e Questionários
9.
Photochem Photobiol ; 84(2): 444-9, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18248503

RESUMO

We compared the frequency and spectra of p53 mutations in skin tumors from UVB-irradiated and benzo(a)pyrene-UVA-treated SKH-1 mice. Analysis of p53 mutations using a combination of polymerase chain reaction, denaturing high-performance liquid chromatography, and sequencing shows that the frequency and spectrum of p53 mutations in BaP-UVA-induced tumors are quite different from those in UVB-induced tumors. SKH-1 mice were treated with BaP-UVA or UVB for 30 weeks after which skin tumors were collected for analysis of p53 mutations. Among the 11 BaP-UVA-induced tumors with diameters of 5-10 mm, two displayed mutations in exon 8 yielding a mutation frequency of 18.2%. In contrast, the mutation frequency among BaP-UVA-induced tumors was 10.5%. In UVB-induced tumors, the mutation frequency in exon 8 was highly correlated with tumor size. A total of 77.8% of tumors with diameters larger than 10 mm contained p53 mutations. The overall mutation frequency among UVB-induced tumors was 17.9% in exon 8 and only 3.8% in exon 5. Hotspots for p53 mutation in UVB-induced tumors were found at codons 128 and 149 (exon 5), and at codons 268, 270, 271 and 273-276 (exon 8). In addition to widely recognized C-->T missense mutations, there were also tandem CC-->AG changes coupled with either an insertion of T, a C-->G substitution or G-->C/T mutations. All of the mutations were found at tri- or tetra-pyrimidine sites. Thirty-nine per cent of all p53 mutations occurred at codons 274 and 275; 53% occurred at codons 268-271. Two multiple mutation clusters were located at codons 268-271 and 274-276. Both BaP-UVA and UVB caused C-->T transitions at codon 275 in exon 8. A C-->T mutation at codon 294 was induced only by BaP-UVA treatment. In contrast to UVB treatment, BaP-UVA treatment did not induce any mutations in exon 5. We show that individually subcarcinogenic levels of BaP and UVA synergistically induce a novel p53-mutation fingerprint. This fingerprint could serve as a prognostic indicator for the development of BaP-UVA-induced skin tumors.


Assuntos
Benzo(a)pireno/toxicidade , Carcinógenos/toxicidade , Genes p53 , Mutação , Neoplasias Induzidas por Radiação/genética , Neoplasias Cutâneas/genética , Raios Ultravioleta , Animais , Éxons , Feminino , Camundongos , Camundongos Pelados , Neoplasias Cutâneas/induzido quimicamente , Neoplasias Cutâneas/etiologia
10.
Carcinogenesis ; 27(8): 1627-35, 2006 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16522663

RESUMO

Genistein, the most abundant isoflavone of the soy derived phytoestrogen compounds, is a potent antioxidant and inhibitor of tyrosine kinase. We previously reported the antiphotocarcinogenic effects of genistein in SKH-1 murine skin, including its capacity for scavenging reactive oxygen species, inhibiting photodynamic DNA damage and downregulating UVB(ultra violet B)-induced signal transduction cascades in carcinogenesis. In this study we elucidate genistein's photoprotective efficacy within the context of full thickness human reconstituted skin relative to acute challenges with ultraviolet-B irradiation. Skin samples were pre-treated with three concentrations of genistein (10, 20 and 50 microM) 1 h prior to UVB radiation at 20 and 60 mJ/cm2. Proliferating cell nuclear antigen (PCNA) and pyrimidine dimer (PD) expression profiles were localized using immunohistochemical analysis on paraffin embedded samples 6 and 12 h post UVB exposure. Genistein dose dependently preserved cutaneous proliferation and repair mechanics at 20 and 60 mJ/cm2, as evidenced by the preservation of proliferating cell populations with increasing genistein concentrations and noticeable paucity in PCNA immunoreactivity in the absence of genistein. Genistein inhibited UV-induced DNA damage, evaluated with PD immunohistochemical expression profiles, demonstrated an inverse relationship with increasing topical genistein concentrations. Irradiation at 20 and 60 mJ/cm2 substantially induced PD formation in the absence of genistein, and a dose dependent inhibition of UVB-induced PD formation was observed relative to increasing genistein concentrations. Collectively all genistein pre-treated samples demonstrated appreciable histologic architectural preservation when compared with untreated specimens. These findings represent a critical link between our animal and cell culture studies with those of human skin and represent the first characterization of the dynamic alterations of UV-induced DNA damage and proliferating cell populations relative to pretreatment with genistein in human reconstituted skin. The implications of our findings serve as compelling validation to our conclusions that genistein may serve as a potent chemopreventive agent against photocarcinogenesis.


Assuntos
Anticarcinógenos/uso terapêutico , Dermatologia , Genisteína/uso terapêutico , Antígeno Nuclear de Célula em Proliferação/metabolismo , Dímeros de Pirimidina , Neoplasias Cutâneas/prevenção & controle , Pele , Raios Ultravioleta/efeitos adversos , Células Cultivadas , Epiderme/efeitos dos fármacos , Epiderme/metabolismo , Epiderme/efeitos da radiação , Humanos , Pele/efeitos dos fármacos , Pele/metabolismo , Pele/efeitos da radiação , Neoplasias Cutâneas/metabolismo , Pele Artificial
11.
Int J Cancer ; 116(2): 193-9, 2005 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-15800929

RESUMO

Combined subcarcinogenic doses of benzo[a]pyrene (BaP) and UVA induced H-ras, but not p53, gene mutations 8 weeks before tumor emergence in SKH-1 mice. Neither UVA (40 kJ/m2) nor BaP (8 nmol) induced any tumors after mice were topically treated 3 times/week for 25 weeks. However, combined BaP-UVA treatment synergistically increased tumor incidence and multiplicity. All tumors induced by BaP-UVA were malignant. The epidermis was collected from mice treated for 2, 6 and 10 weeks. DNA from UVB- (0.3 kJ/m2) or BaP-UVA-(8 nmol and 40 kJ/m2-induced tumors was isolated and screened for H-ras and p53 mutations. Four types of point mutation, GGC-->GAC, GCC, GTC and CGC, occurred in UVB-induced tumors at H-ras codon 13; and one type of point mutation, GGA-->GAA, at codon 12. Treatment with either BaP alone or BaP-UVA for 10 weeks caused GGA-->GAA mutation at codon 12 or GGC-->GAC mutation at codon 13 in nontumor skin, respectively, as well as in tumors induced by BaP-UVA. All of the 10-week samples treated with either BaP or BaP-UVA showed detectable mutations at codons 12 and 13, but the genetic load was significantly higher in BaP-UVA-treated mice than in those exposed only to BaP. UVA alone induced mutations at codon 12 in only one-third of samples. G-->A mutations induced by BaP or BaP-UVA at position 38 of codon 13 have not been reported previously. C-->T transitions were detected in p53 hot spots of exon 8 in 2 of 19 BaP-UVA-induced tumors but were not found in nontumor skin.


Assuntos
Benzo(a)pireno/toxicidade , Genes ras , Neoplasias Cutâneas/etiologia , Raios Ultravioleta/efeitos adversos , Animais , Códon , Análise Mutacional de DNA , Feminino , Genes p53 , Camundongos , Mutação Puntual , Neoplasias Cutâneas/patologia , Neoplasias Cutâneas/veterinária
12.
Photochem Photobiol ; 80(3): 587-95, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15623348

RESUMO

Proliferating cell nuclear antigen (PCNA) is an active nuclear protein involved in DNA replication, recombination and repair. PCNA is found throughout the basal layer in normal skin and in all layers of the epidermis in malignancy. This study evaluates PCNA's expression after acute and chronic UV-B irradiation. Skh-1 hairless mice exposed to 1.5 and 4.5 kJ/m2 of UV-B were sacrificed at 6, 12, 24, 48, 72 and 168 h. Immunohistochemical analysis revealed PCNA expression throughout the basal layer of untreated skin, with diminished expression at 6 h, indicative of immediate UV damage, and evidenced by the observable upregulation in pyrimidine dimer formation early on. Subsequently, PCNA immunoreactivity progressively increased, demonstrating an aberrant upward epidermal migratory pattern in association with chronic exposure. The 4.5 kJ/m2 group exhibited prolonged recovery in staining and also demonstrated this altered migratory pattern with chronic exposure. Progressive reactivation of PCNA expression occurs with repair. PCNA migration to upper layers of the epidermis indicates proliferation and possibly a subsequent increased malignant potential. We conclude that PCNA can serve as a marker of DNA repair and indirectly as an indicator of UV-B-induced damage, expression being time dependent and dose related. Specific immunoreactivity patterns and the observable atypia in keratinocytes are relevant in elucidating malignant potentiation.


Assuntos
Regulação da Expressão Gênica/efeitos da radiação , Antígeno Nuclear de Célula em Proliferação/metabolismo , Pele/metabolismo , Pele/efeitos da radiação , Raios Ultravioleta , Animais , Feminino , Imuno-Histoquímica , Camundongos
13.
J Nutr ; 133(11 Suppl 1): 3811S-3819S, 2003 11.
Artigo em Inglês | MEDLINE | ID: mdl-14608119

RESUMO

Genistein is a soybean isoflavone with diverse biological activities. It is a potent antioxidant, a specific inhibitor of protein tyrosine kinase, and a phytoestrogen. In recent years, increasing evidence has accumulated that this natural ingredient shows preventative and therapeutic effects for breast and prostate cancers, postmenopausal syndrome, osteoporosis, and cardiovascular diseases in animals and humans. In the past decade we have conducted a series of studies and demonstrated that genistein has significant antiphotocarcinogenic and antiphotoaging effects. Genistein substantially inhibits skin carcinogenesis and cutaneous aging induced by ultraviolet (UV) light in mice, and photodamage in humans. The mechanisms of action involve protection of oxidative and photodynamically damaged DNA, downregulation of UVB-activated signal transduction cascades, and antioxidant activities. In this article, we review the biological activities of genistein, as well as published and unpublished research from our laboratory. In addition, we discuss the potential application of genistein to clinical dermatology.


Assuntos
Anticarcinógenos/uso terapêutico , Genisteína/uso terapêutico , Neoplasias Cutâneas/prevenção & controle , Pele/efeitos dos fármacos , Animais , Humanos , Camundongos , Neoplasias Induzidas por Radiação/prevenção & controle , Fitoterapia , Envelhecimento da Pele/efeitos dos fármacos , Glycine max , Raios Ultravioleta
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