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BACKGROUND AND OBJECTIVE: Sutureless scleral fixation is an effective technique for placement of a secondary intraocular lens. The authors propose a modification that may simplify intraoperative technical challenges. STUDY DESIGN: Description of surgical technique. RESULTS: Successful placement of stable secondary intraocular lens. CONCLUSION: This modified technique has the potential to reduce intraoperative complications. Studies including more patients with longer follow-up are needed to test the viability.
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Catéteres Venosos Centrales , Cápsula del Cristalino/patología , Implantación de Lentes Intraoculares/métodos , Esclerótica/cirugía , Humanos , Implantación de Lentes Intraoculares/instrumentación , Esclerostomía , Colgajos Quirúrgicos , VitrectomíaRESUMEN
PURPOSE: To describe the application of nonparametric multivariate statistical methods to the analysis of astigmatism treatment outcomes. SETTING: Jules Stein Eye Institute and Department of Ophthalmology, David Geffen School of Medicine at UCLA, Los Angeles, California, USA. METHODS: Nonparametric methods were applied to a published data set and to 12 test data sets created for test purposes. Results of 3 multivariate nonparametric tests were compared with those obtained using the Hotelling T(2), a multivariate parametric test. The nonparametric tests were the rank-based multivariate analysis of variance (MANOVA), sign-based MANOVA, and bootstrapping based on the Hotelling T(2) statistic. RESULTS: Reanalysis of the published data set using the 3 nonparametric tests detected statistically significant treatment effects at all postoperative examinations. The Hotelling T(2) and 3 nonparametric tests detected differences in astigmatism outcomes for multiple test data sets that simulated normal distributions. For test data sets simulating non-normal distributions, the Hotelling T(2) test and bootstrapping based on Hotelling T(2) detected a difference in 1 test data set while rank-based and sign-based MANOVA detected differences in outcomes for multiple data sets. CONCLUSIONS: Rank-based and sign-based MANOVA had comparable or slightly lower power than the Hotelling T(2) test in detecting differences in normally distributed data. For data sets in which the rectangular components of astigmatism vectors do not distribute normally in both dimensions, only the nonparametric statistical methods were valid. The sign-based MANOVA was the most sensitive in detecting differences in non-normally distributed astigmatism outcomes in the data sets.
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Astigmatismo/diagnóstico , Implantación de Lentes Intraoculares , Facoemulsificación , Estadísticas no Paramétricas , Astigmatismo/etiología , Córnea/cirugía , Humanos , Análisis Multivariante , Complicaciones Posoperatorias , Seudofaquia , Esclerótica/cirugía , Colgajos QuirúrgicosRESUMEN
NFkappaB is an inducible transcription factor that controls kinetically complex patterns of gene expression. Several studies reveal multiple pathways linking NFkappaB to the promotion and progression of various cancers. Despite extensive interest and characterization, many NFkappaB controlled genes still remain to be identified. We used chromatin immunoprecipitation combined with microarray technology (ChIP/chip) to investigate the dynamic interaction of NFkappaB with the promoter regions of 100 genes known to be expressed in mitogen-induced T-cells. Six previously unrecognized NFkappaB controlled genes (ATM, EP300, TGFbeta, Selectin, MMP-1 and SFN) were identified. Each gene is induced in mitogen-stimulated T-cells, repressed by pharmacological NFkappaB blockade, reduced in cells deficient in the p50 NFkappaB subunit and dramatically repressed by RNAi specifically designed against cRel. A coregulatory role for Ets transcription factors in the expression of the NFkappaB controlled genes was predicted by comparative promoter analysis and confirmed by ChIP and by functional disruption of Ets. NFkappaB deficiency produces a deficit in ATM function and DNA repair indicating an active role for NFkappaB in maintaining DNA integrity. These results define new potential targets and transcriptional networks governed by NFkappaB and provide novel functional insights for the role of NFkappaB in genomic stability, cell cycle control, cell-matrix and cell-cell interactions during tumor progression.
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Redes Reguladoras de Genes , FN-kappa B/metabolismo , Proteínas Proto-Oncogénicas c-rel/metabolismo , Proteínas 14-3-3/genética , Proteínas 14-3-3/metabolismo , Proteínas de la Ataxia Telangiectasia Mutada , Proteínas de Ciclo Celular/genética , Proteínas de Ciclo Celular/metabolismo , Línea Celular , Inmunoprecipitación de Cromatina , Proteínas de Unión al ADN/genética , Proteínas de Unión al ADN/metabolismo , Proteína p300 Asociada a E1A/genética , Proteína p300 Asociada a E1A/metabolismo , Perfilación de la Expresión Génica , Humanos , Selectina L/genética , Selectina L/metabolismo , Metaloproteinasa 1 de la Matriz/genética , Metaloproteinasa 1 de la Matriz/metabolismo , FN-kappa B/genética , Análisis de Secuencia por Matrices de Oligonucleótidos , Regiones Promotoras Genéticas , Proteínas Serina-Treonina Quinasas/genética , Proteínas Serina-Treonina Quinasas/metabolismo , Proteínas Proto-Oncogénicas c-rel/genética , Interferencia de ARN , Linfocitos T/inmunología , Linfocitos T/metabolismo , Factor de Crecimiento Transformador beta1/genética , Factor de Crecimiento Transformador beta1/metabolismo , Proteínas Supresoras de Tumor/genética , Proteínas Supresoras de Tumor/metabolismoRESUMEN
Global genomic approaches in cancer research have provided new and innovative strategies for the identification of signatures that differentiate various types of human cancers. Computational analysis of the promoter composition of the genes within these signatures may provide a powerful method for deducing the regulatory transcriptional networks that mediate their collective function. In this study we have systematically analyzed the promoter composition of gene classes derived from previously established genetic signatures that recently have been shown to reliably and reproducibly distinguish five molecular subtypes of breast cancer associated with distinct clinical outcomes. Inferences made from the trends of transcription factor binding site enrichment in the promoters of these gene groups led to the identification of regulatory pathways that implicate discrete transcriptional networks associated with specific molecular subtypes of breast cancer. One of these inferred pathways predicted a role for nuclear factor-kappaB in a novel feed-forward, self-amplifying, autoregulatory module regulated by the ERBB family of growth factor receptors. The existence of this pathway was verified in vivo by chromatin immunoprecipitation and shown to be deregulated in breast cancer cells overexpressing ERBB2. This analysis indicates that approaches of this type can provide unique insights into the differential regulatory molecular programs associated with breast cancer and will aid in identifying specific transcriptional networks and pathways as potential targets for tumor subtype-specific therapeutic intervention.
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Biomarcadores de Tumor/genética , Neoplasias de la Mama/genética , Redes Reguladoras de Genes/genética , Regiones Promotoras Genéticas/genética , Línea Celular Tumoral , Inmunoprecipitación de Cromatina , Análisis por Conglomerados , Progresión de la Enfermedad , Femenino , Genes Relacionados con las Neoplasias , Humanos , Análisis de Componente PrincipalRESUMEN
Multiple variants of the vascular adhesion molecule-1 (VCAM1) promoter show increased nucleotide heterozygosity in the African American population. Using a novel transfection-based transcriptional pathway profiling method, we show that select uncommon variants are functionally hyperactive. Eight candidate VCAM1 promoter haplotypes comprising 13 previously identified SNPs were assessed for response to known mitogens. Activity was correlated with bioinformatic analysis of hyper- and hyporesponsive variants to identify the gain or loss of haplotype-specific transcription factor binding site (TFBS). Using this approach, a low frequency regulatory allele (c.-540A>G; dbSNP rs3783605:A>G), found in a hyperactive VCAM1 promoter haplotype, was shown to create a candidate binding site for ETS2 that was confirmed in vivo by chromatin immunoprecipitation. This report provides the first functional evaluation of VCAM1 promoter polymorphisms and establishes a hypothetical foundation for investigation of their role in the pathogenesis of VCAM1-associated diseases that disproportionately afflict African Americans, including thromboembolic diseases, asthma, and multiple myeloma.
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Negro o Afroamericano/genética , Polimorfismo de Nucleótido Simple/genética , Regiones Promotoras Genéticas/genética , Molécula 1 de Adhesión Celular Vascular/genética , Secuencia de Bases , Haplotipos , Humanos , Células Jurkat , Mitógenos/farmacología , Datos de Secuencia Molecular , Transcripción Genética/efectos de los fármacosRESUMEN
BACKGROUND: The purpose of this study is to determine whether or not there exists nonrandom grouping of cis-regulatory elements within gene promoters that can be perceived independent of gene expression data and whether or not there is any correlation between this grouping and the biological function of the gene. RESULTS: Using ProSpector, a web-based promoter search and annotation tool, we have applied an unbiased approach to analyze the transcription factor binding site frequencies of 1400 base pair genomic segments positioned at 1200 base pairs upstream and 200 base pairs downstream of the transcriptional start site of 7298 commonly studied human genes. Partitional clustering of the transcription factor binding site composition within these promoter segments reveals a small number of gene groups that are selectively enriched for gene ontology terms consistent with distinct aspects of cellular function. Significance ranking of the class-determining transcription factor binding sites within these clusters show substantial overlap between the gene ontology terms of the transcriptions factors associated with the binding sites and the gene ontology terms of the regulated genes within each group. CONCLUSION: Thus, gene sorting by promoter composition alone produces partitions in which the "regulated" and the "regulators" cosegregate into similar functional classes. These findings demonstrate that the transcription factor binding site composition is non-randomly distributed between gene promoters in a manner that reflects and partially defines general gene class function.