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1.
Sensors (Basel) ; 22(11)2022 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-35684774

RESUMO

Structural health monitoring has multifold aims. Concerning composite structures, the main objectives are perhaps reducing costs by shifting from scheduled to on-demand maintenance and reducing weight by removing redundant precautions as the insertion of chicken fasteners to for ensuring joint safety in cases of bonding layer fail. Adhesion defects may be classified along different types, for instance distinguishing between glue deficiency or de-bonding. This paper deals with a preliminary numerical characterization of adhesive layer imperfections on a representative aircraft component. The multipart composite spar is made of two plates and two corresponding C-beams, bonded together to form an almost squared boxed section beam. A numerical test campaign was devoted to extract relevant information from different defect layouts and to try to assess some parameters that could describe their peculiarities. A focus was then given to macroscopic evidence of fault effects behavior, as localization, reciprocal interference, impact on structural response, and so on. A proprietary code was finally used to retrieve the presence and size of the imperfections, correlating numerical outcomes with estimations. Activities were performed along OPTICOMS, a European project funded within the Clean Sky 2 Joint Technology Initiative (JTI).


Assuntos
Adesivos , Adesivos/química
2.
Ophthalmic Plast Reconstr Surg ; 33(5): e118-e120, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-27879619

RESUMO

Surgical repair of orbital fractures with implants is a widely used treatment modality. While a variety of established complications are associated with this technique, most are directly understood and treated. Bloody epiphora is a finding with potentially ominous causes. The authors present a unique case of bloody epiphora, accompanied by orbital hemorrhage arising several years after orbital floor fracture repair, due to erosion of the nasolacrimal drainage system by a displaced implant combined with anticoagulation. The collection and evaluation of all protected patient health information was compliant with the regulations and conditions set forth in the Health Insurance Portability and Availability Act of 1996.


Assuntos
Doenças do Aparelho Lacrimal/etiologia , Fraturas Orbitárias/complicações , Implantes Orbitários/efeitos adversos , Hemorragia Pós-Operatória/etiologia , Descompressão Cirúrgica/métodos , Feminino , Seguimentos , Humanos , Doenças do Aparelho Lacrimal/diagnóstico , Doenças do Aparelho Lacrimal/cirurgia , Pessoa de Meia-Idade , Fraturas Orbitárias/diagnóstico , Fraturas Orbitárias/cirurgia , Hemorragia Pós-Operatória/diagnóstico , Hemorragia Pós-Operatória/cirurgia , Fatores de Tempo , Tomografia Computadorizada por Raios X
3.
PLoS One ; 7(10): e46742, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23110055

RESUMO

Fuchs endothelial corneal dystrophy (FECD) is the most common late-onset, vision-threatening corneal dystrophy in the United States, affecting about 4% of the population. Advanced FECD involves a thickening of the cornea from stromal edema and changes in Descemet membrane. To understand the relationship between FECD and central corneal thickness (CCT), we characterized common genetic variation in COL8A2 and TCF4, genes previously implicated in CCT and/or FECD. Other genes previously associated with FECD (PITX2, ZEB1, SLC4A11), and genes only known to affect CCT (COL5A1, FOXO1, AVGR8, ZNF469) were also interrogated. FECD probands, relatives and controls were recruited from 32 clinical sites; a total of 532 cases and 204 controls were genotyped and tested for association of FECD case/control status, a 7-step FECD severity scale and CCT, adjusting for age and sex. Association of FECD grade with TCF4 was highly significant (OR= 6.01 at rs613872; p = 4.8×10(-25)), and remained significant when adjusted for changes in CCT (OR= 4.84; p = 2.2×10(-16)). Association of CCT with TCF4 was also significant (p = 6.1×10(-7)), but was abolished with adjustment for FECD grade (p = 0.92). After adjusting for FECD grade, markers in other genes examined were modestly associated (p ∼ 0.001) with FECD and/or CCT. Thus, common variants in TCF4 appear to influence FECD directly, and CCT secondarily via FECD. Additionally, changes in corneal thickness due to the effect of other loci may modify disease severity, age-at-onset, or other biomechanical characteristics.


Assuntos
Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos/genética , Colágeno Tipo VIII/genética , Córnea/metabolismo , Córnea/patologia , Distrofia Endotelial de Fuchs/genética , Distrofia Endotelial de Fuchs/patologia , Fatores de Transcrição/genética , Idoso , Feminino , Genótipo , Haplótipos , Humanos , Desequilíbrio de Ligação/genética , Masculino , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único/genética , Fator de Transcrição 4
4.
Ophthalmology ; 119(8): 1596-603, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22521086

RESUMO

PURPOSE: This study evaluates the prognostic performance of a 15 gene expression profiling (GEP) assay that assigns primary posterior uveal melanomas to prognostic subgroups: class 1 (low metastatic risk) and class 2 (high metastatic risk). DESIGN: Prospective, multicenter study. PARTICIPANTS: A total of 459 patients with posterior uveal melanoma were enrolled from 12 independent centers. TESTING: Tumors were classified by GEP as class 1 or class 2. The first 260 samples were also analyzed for chromosome 3 status using a single nucleotide polymorphism assay. Net reclassification improvement analysis was performed to compare the prognostic accuracy of GEP with the 7th edition clinical Tumor-Node-Metastasis (TNM) classification and chromosome 3 status. MAIN OUTCOME MEASURES: Patients were managed for their primary tumor and monitored for metastasis. RESULTS: The GEP assay successfully classified 446 of 459 cases (97.2%). The GEP was class 1 in 276 cases (61.9%) and class 2 in 170 cases (38.1%). Median follow-up was 17.4 months (mean, 18.0 months). Metastasis was detected in 3 class 1 cases (1.1%) and 44 class 2 cases (25.9%) (log-rank test, P<10(-14)). Although there was an association between GEP class 2 and monosomy 3 (Fisher exact test, P<0.0001), 54 of 260 tumors (20.8%) were discordant for GEP and chromosome 3 status, among which GEP demonstrated superior prognostic accuracy (log-rank test, P = 0.0001). By using multivariate Cox modeling, GEP class had a stronger independent association with metastasis than any other prognostic factor (P<0.0001). Chromosome 3 status did not contribute additional prognostic information that was independent of GEP (P = 0.2). At 3 years follow-up, the net reclassification improvement of GEP over TNM classification was 0.43 (P = 0.001) and 0.38 (P = 0.004) over chromosome 3 status. CONCLUSIONS: The GEP assay had a high technical success rate and was the most accurate prognostic marker among all of the factors analyzed. The GEP provided a highly significant improvement in prognostic accuracy over clinical TNM classification and chromosome 3 status. Chromosome 3 status did not provide prognostic information that was independent of GEP.


Assuntos
Biomarcadores Tumorais/genética , Perfilação da Expressão Gênica , Melanoma/genética , Neoplasias Uveais/genética , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Cromossomos Humanos Par 3/genética , Feminino , Seguimentos , Regulação Neoplásica da Expressão Gênica/fisiologia , Humanos , Masculino , Melanoma/patologia , Pessoa de Meia-Idade , Análise de Sequência com Séries de Oligonucleotídeos , Polimorfismo de Nucleotídeo Único , Prognóstico , Estudos Prospectivos , Reação em Cadeia da Polimerase em Tempo Real , Neoplasias Uveais/patologia , Adulto Jovem
5.
Cornea ; 31(1): 26-35, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22045388

RESUMO

PURPOSE: To describe the methods for family and case-control recruitment for a multicenter genetic and associated heritability analyses of Fuchs endothelial corneal dystrophy (FECD). METHODS: Twenty-nine enrolling sites with 62 trained investigators and coordinators gathered individual and family information, graded the phenotype, and collected blood and/or saliva for genetic analysis on all individuals with and without FECD. The degree of FECD was assessed in a 0 to 6 semiquantitative scale using standardized clinical methods with pathological verification of FECD on at least 1 member of each family. Central corneal thickness was measured by ultrasonic pachymetry. RESULTS: Three hundred twenty-two families with 330 affected sibling pairs with FECD were enrolled and included a total of 650 sibling pairs of all disease grades. Using the entire 7-step FECD grading scale or a dichotomous definition of severe disease, heritability was assessed in families via sib-sib correlations. Both binary indicators of severe disease and semiquantitative measures of disease severity were significantly heritable, with heritability estimates of 30% for severe disease, 37% to 39% for FECD score, and 47% for central corneal thickness. CONCLUSIONS: Genetic risk factors have a strong role in the severity of the FECD phenotype and corneal thickness. Genotyping this cohort with high-density genetic markers followed by appropriate statistical analyses should lead to novel loci for disease susceptibility.


Assuntos
Mapeamento Cromossômico , Distrofia Endotelial de Fuchs/genética , Idoso , Estudos de Casos e Controles , Estudos de Coortes , Córnea/patologia , Feminino , Distrofia Endotelial de Fuchs/patologia , Predisposição Genética para Doença , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Fenótipo
6.
PLoS Genet ; 5(7): e1000584, 2009 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19649315

RESUMO

Age-related cataract is a major cause of blindness worldwide, and cortical cataract is the second most prevalent type of age-related cataract. Although a significant fraction of age-related cataract is heritable, the genetic basis remains to be elucidated. We report that homozygous deletion of Epha2 in two independent strains of mice developed progressive cortical cataract. Retroillumination revealed development of cortical vacuoles at one month of age; visible cataract appeared around three months, which progressed to mature cataract by six months. EPHA2 protein expression in the lens is spatially and temporally regulated. It is low in anterior epithelial cells, upregulated as the cells enter differentiation at the equator, strongly expressed in the cortical fiber cells, but absent in the nuclei. Deletion of Epha2 caused a significant increase in the expression of HSP25 (murine homologue of human HSP27) before the onset of cataract. The overexpressed HSP25 was in an underphosphorylated form, indicating excessive cellular stress and protein misfolding. The orthologous human EPHA2 gene on chromosome 1p36 was tested in three independent worldwide Caucasian populations for allelic association with cortical cataract. Common variants in EPHA2 were found that showed significant association with cortical cataract, and rs6678616 was the most significant in meta-analyses. In addition, we sequenced exons of EPHA2 in linked families and identified a new missense mutation, Arg721Gln, in the protein kinase domain that significantly alters EPHA2 functions in cellular and biochemical assays. Thus, converging evidence from humans and mice suggests that EPHA2 is important in maintaining lens clarity with age.


Assuntos
Catarata/genética , Catarata/metabolismo , Receptor EphA2/genética , Receptor EphA2/metabolismo , Fatores Etários , Idoso , Animais , Catarata/patologia , Cromossomos Humanos Par 1/genética , Estudos de Coortes , Modelos Animais de Doenças , Feminino , Humanos , Cristalino/química , Cristalino/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Pessoa de Meia-Idade , Dados de Sequência Molecular , Mutação , Polimorfismo de Nucleotídeo Único , Estrutura Terciária de Proteína , Receptor EphA2/química , Alinhamento de Sequência , Córtex Visual/química , Córtex Visual/metabolismo , População Branca/genética
7.
Mol Pharm ; 6(5): 1417-28, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19445482

RESUMO

Magnetic targeting is useful for intravascular or intracavitary drug delivery, including tumor chemotherapy or intraocular antiangiogenic therapy. For all such in vivo applications, the magnetic drug carrier must be biocompatible and nontoxic. In this work, we investigated the toxic properties of magnetic nanoparticles coated with polyethylenoxide (PEO) triblock copolymers. Such coatings prevent the aggregation of magnetic nanoparticles and guarantee consistent magnetic and nonmagnetic flow properties. It was found that the PEO tail block length inversely correlates with toxicity. The nanoparticles with the shortest 0.75 kDa PEO tails were the most toxic, while particles coated with the 15 kDa PEO tail block copolymers were the least toxic. Toxicity responses of the tested prostate cancer cell lines (PC3 and C4-2), human umbilical vein endothelial cells (HUVECs), and human retinal pigment epithelial cells (HRPEs) were similar. Furthermore, all cell types took up the coated magnetic nanoparticles. It is concluded that magnetite nanoparticles coated with triblock copolymers containing PEO tail lengths of above 2 kDa are biocompatible and appropriate for in vivo application.


Assuntos
Óxido Ferroso-Férrico/farmacocinética , Óxido Ferroso-Férrico/toxicidade , Nanopartículas Metálicas/toxicidade , Transporte Biológico Ativo , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Sistemas de Liberação de Medicamentos , Células Endoteliais/efeitos dos fármacos , Óxido Ferroso-Férrico/administração & dosagem , Humanos , Masculino , Teste de Materiais , Nanopartículas Metálicas/administração & dosagem , Nanopartículas Metálicas/química , Nanopartículas Metálicas/ultraestrutura , Microscopia Eletrônica de Transmissão , Nanotecnologia , Tamanho da Partícula , Polietilenoglicóis/química , Neoplasias da Próstata/tratamento farmacológico , Neoplasias da Próstata/patologia , Epitélio Pigmentado da Retina/citologia , Epitélio Pigmentado da Retina/efeitos dos fármacos
9.
Invest Ophthalmol Vis Sci ; 44(9): 3986-92, 2003 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-12939319

RESUMO

PURPOSE: In humans, mutations in protocadherin 15 are known to result in Usher Syndrome type 1F (USH1F). Patients with USH1F are born with profound hearing loss and have visual problems that develop in late childhood. Based on the phenotypic hearing loss and an associated mutation in protocadherin 15 (Pcdh15), the Ames waltzer mice have been presented as potential models for USH1F. To determine whether the Ames waltzer is a model for retinopathy in USH1F, retinal structure and function were assessed in all four available alleles of the mouse. METHODS: Activity of both the rod and cone pathways was evaluated by measuring electroretinograms (ERGs) in response to strobe flashes under dark- and light-adapted conditions, respectively. Retinas were processed with standard histochemical procedures, and retinal morphology was examined. The neural retina was dissected from normal pigmented mice at postnatal day (P)0, P5, P7, P20, P40, and P70, and the presence of Pcdh15 was determined by RT-PCR. RESULTS: The amplitude and implicit time of both the rod- and cone-mediated ERG a- and b-waves were comparable between Ames waltzer mutants and heterozygous littermates as old as 13 months. No evidence of retinal degeneration or disorganization was detected in mutant mice. Measures of retinal layer thicknesses were similar in mutant and wild-type control animals. Retinal expression of Pcdh15 was observed at all ages examined between P0 and P70. CONCLUSIONS: Although Pcdh15 is present in neural retina, its role remains unclear. Mutations in the Pcdh15 did not result in retinal abnormalities in the four alleles of Ames waltzer tested in this study. The explanation for the absence of retinal phenotype in the Ames mouse should be helpful in understanding USH1F and developing treatments for this disorder.


Assuntos
Modelos Animais de Doenças , Perda Auditiva/fisiopatologia , Células Fotorreceptoras de Vertebrados/fisiologia , Degeneração Retiniana/fisiopatologia , Doenças Vestibulares/fisiopatologia , Animais , Proteínas Relacionadas a Caderinas , Caderinas/genética , Caderinas/metabolismo , Adaptação à Escuridão , Eletrorretinografia , Genes Recessivos , Perda Auditiva/congênito , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Mutantes , Mutação , Fenótipo , Estimulação Luminosa , Precursores de Proteínas/genética , Precursores de Proteínas/metabolismo , RNA Mensageiro/metabolismo , Degeneração Retiniana/genética , Degeneração Retiniana/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Síndrome , Doenças Vestibulares/genética
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