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1.
Am J Ophthalmol Case Rep ; 26: 101514, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35464689

RESUMO

Purpose: To report novel life-threatening coronary and systemic arterial disease associated with Retinal Arterial Macroaneurysms with Supravalvular Pulmonic Stenosis (RAMSVPS) syndrome, previously known as Familial Retinal Arterial Macroaneurysms (FRAM). Observations: A 29-years old woman with longstanding poor vision in her right eye presented with acute myocardial infarction and subclavian bruit. Her polyangiogram showed peculiar ostial coronary aneurysms, left anterior descending coronary artery stenosis, occlusion of the left subclavian artery, stenosis of both renal arteries, irregularities in the mesenteric artery and tapering of the aorta. Takayasu arteritis was initially presumed, however fundus examination revealed beading and macroaneurysms along major retinal arteries, intraretinal exudation and hemorrhages, retinal arterial sheathing and stenosis, Coats'-like features and submacular gliosis in the right eye, vitreous hemorrhage in the left eye, and persistent hyaloid artery remnant in both eyes. These features evoked RAMSVPS syndrome. Genetic testing identified the same homozygous IGFBP7 c.830-1G > A mutation reported with RAMSVPS syndrome, rectifying the systemic diagnosis. Conclusion and importance: RAMSVPS syndrome can be associated with more life-threatening coronary and widespread major arterial disease than previously recognized. It is crucial for ophthalmologists to recognize RAMSVPS syndrome and refer patients for a thorough cardiovascular evaluation. Likewise, a careful retinal examination and the possibility of an IGFBP7 mutation should be considered in the setting of systemic arterial or cardiac disease.

2.
Hum Mol Genet ; 30(1): 72-77, 2021 03 25.
Artigo em Inglês | MEDLINE | ID: mdl-33450762

RESUMO

Ocular pterygium-digital keloid dysplasia (OPDKD) presents in childhood with ingrowth of vascularized connective tissue on the cornea leading to severely reduced vision. Later the patients develop keloids on digits but are otherwise healthy. The overgrowth in OPDKD affects body parts that typically have lower temperature than 37°C. We present evidence that OPDKD is associated with a temperature sensitive, activating substitution, p.(Asn666Tyr), in PDGFRB. Phosphorylation levels of PDGFRB and downstream targets were higher in OPDKD fibroblasts at 37°C but were further greatly increased at the average corneal temperature of 32°C. This suggests that the substitution cause significant constitutive autoactivation mainly at lower temperature. In contrast, a different substitution in the same codon, p.(Asn666Ser), is associated with Penttinen type of premature aging syndrome. This devastating condition is characterized by widespread tissue degeneration, including pronounced chronic ulcers and osteolytic resorption in distal limbs. In Penttinen syndrome fibroblasts, equal and high levels of phosphorylated PDGFRB was present at both 32°C and 37°C. This indicates that this substitution causes severe constitutive autoactivation of PDGFRB regardless of temperature. In line with this, most downstream targets were not affected by lower temperature. However, STAT1, important for tissue wasting, did show further increased phosphorylation at 32°C. Temperature-dependent autoactivation offers an explanation to the strikingly different clinical outcomes of substitutions in the Asn666 codon of PDGFRB.


Assuntos
Acro-Osteólise/genética , Túnica Conjuntiva/anormalidades , Deformidades Congênitas dos Membros/genética , Progéria/genética , Pterígio/genética , Receptor beta de Fator de Crescimento Derivado de Plaquetas/genética , Anormalidades da Pele/genética , Acro-Osteólise/diagnóstico por imagem , Acro-Osteólise/patologia , Adolescente , Adulto , Substituição de Aminoácidos/genética , Criança , Pré-Escolar , Túnica Conjuntiva/diagnóstico por imagem , Túnica Conjuntiva/patologia , Feminino , Humanos , Lactente , Deformidades Congênitas dos Membros/diagnóstico por imagem , Deformidades Congênitas dos Membros/patologia , Masculino , Mutação de Sentido Incorreto/genética , Fenótipo , Fosforilação/genética , Progéria/diagnóstico por imagem , Progéria/patologia , Pterígio/diagnóstico por imagem , Pterígio/patologia , Anormalidades da Pele/patologia , Temperatura , Adulto Jovem
3.
Can J Ophthalmol ; 54(2): 247-257, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30975350

RESUMO

OBJECTIVE: Orbital Rhabdomyosarcoma is a highly malignant tumor predominantly affecting children. Our study adds more understanding of this tumor to ophthalmologists from the clinicopathological, radiological and genetic aspects. DESIGN: A retrospective clinicopathological and radiological study of ocular rhabdomyosarcoma with genetic profiling. PARTICIPANTS: All the cases with confirmed tissue diagnosis of orbital rhabdomyosarcoma presenting at a tertiary eye hospital in Riyadh, Saudi Arabia during the period 1985-2015. METHODS: Charts and histological slides of 26 patients were reviewed. DNA was extracted from paraffin-embedded biopsies and genotyping was performed to detect chromosomal abnormalities and Copy-number variations regions. RESULTS: 18 males and 8 females were included with a mean age at presentation of 6.9 years (SD of 4.4). Proptosis and globe displacement were the commonest clinical presentations. Embryonal histopathological type was the commonest (73.1%) with superior orbital involvement (p = 0.024). Using magnetic resonance imaging, the embryonal type showed higher Apparent diffusion coefficient (ADC) value compared to the alveolar type (p = 0.98). Genetic profiling showed Copy-number gain in regions spanning PAX3, DDIT3, Gli, Wnt6 genes. DICER1 gene implication was found in 9 sporadic cases. CONCLUSION: Rhabdomyosarcoma is rare and occurs with a mean age of 7 years, predominantly among males. The commonest embryonal type is significantly correlated with superior orbital involvement. Radiologically, it shows an ADC of 0.67-0.09 × 10-3mm2/s. (p = 0.98). The gain in PAX3, DDIT3, Gli1, Wnt6 genes is a new finding while the DICER1 gene implication in the absence of familial hereditary carcinoma is another interesting finding.


Assuntos
Biomarcadores Tumorais/genética , DNA de Neoplasias/genética , Testes Genéticos/métodos , Imageamento por Ressonância Magnética/métodos , Rabdomiossarcoma/genética , Tomografia Computadorizada por Raios X/métodos , Adolescente , Criança , Pré-Escolar , Feminino , Perfil Genético , Humanos , Lactente , Masculino , Estudos Retrospectivos , Rabdomiossarcoma/diagnóstico , Sequenciamento Completo do Genoma/métodos , Adulto Jovem
4.
Oncogene ; 38(12): 2056-2075, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30401983

RESUMO

Retinoblastoma is the most common intraocular cancer in children. While the primary tumor can often be treated by local or systemic chemotherapy, metastatic dissemination is generally resistant to therapy and remains a leading cause of pediatric cancer death in much of the world. In order to identify new therapeutic targets in aggressive tumors, we sequenced RNA transcripts in five snap frozen retinoblastomas which invaded the optic nerve and five which did not. A three-fold increase was noted in mRNA levels of ACVR1C/ALK7, a type I receptor of the TGF-ß family, in invasive retinoblastomas, while downregulation of DACT2 and LEFTY2, negative modulators of the ACVR1C signaling, was observed in most invasive tumors. A two- to three-fold increase in ACVR1C mRNA was also found in invasive WERI Rb1 and Y79 cells as compared to non-invasive cells in vitro. Transcripts of ACVR1C receptor and its ligands (Nodal, Activin A/B, and GDF3) were expressed in six retinoblastoma lines, and evidence of downstream SMAD2 signaling was present in all these lines. Pharmacological inhibition of ACVR1C signaling using SB505124, or genetic downregulation of the receptor using shRNA potently suppressed invasion, growth, survival, and reduced the protein levels of the mesenchymal markers ZEB1 and Snail. The inhibitory effects on invasion, growth, and proliferation were recapitulated by knocking down SMAD2, but not SMAD3. Finally, in an orthotopic zebrafish model of retinoblastoma, a 55% decrease in tumor spread was noted (p = 0.0026) when larvae were treated with 3 µM of SB505124, as compared to DMSO. Similarly, knockdown of ACVR1C in injected tumor cells using shRNA also resulted in a 54% reduction in tumor dissemination in the zebrafish eye as compared to scrambled shRNA control (p = 0.0005). Our data support a role for the ACVR1C/SMAD2 pathway in promoting invasion and growth of retinoblastoma.


Assuntos
Receptores de Ativinas Tipo I/metabolismo , Retinoblastoma/patologia , Transdução de Sinais , Proteína Smad2/metabolismo , Receptores de Ativinas Tipo I/genética , Linhagem Celular Tumoral , Proliferação de Células , Regulação para Baixo , Regulação Neoplásica da Expressão Gênica , Humanos , Invasividade Neoplásica , Metástase Neoplásica , Fenótipo , Proteína Smad2/genética
5.
Br J Ophthalmol ; 101(7): 933-939, 2017 07.
Artigo em Inglês | MEDLINE | ID: mdl-27899370

RESUMO

BACKGROUND/AIM: Our aim is to the report the clinical and histopathological features of benign reactive lymphoid hyperplasia (BRLH) of the conjunctiva in children and the outcomes of treatment. METHODS: A retrospective chart review was performed for children aged 0-18 years, diagnosed with conjunctival BRLH from January 2000 to December 2013 at two large ophthalmology hospitals in the Middle East. Data were collected on patient demographics, features of the lesions, the site of the lesion, location, adnexal involvement, lymph nodes involvement, local spread, histopathology and molecular genetic studies of the cases (if available), outcomes of treatment and recurrence. RESULTS: There were 24 patients with lymphoid lesions classified as conjunctival BRLH during the 12-year period evaluated in this study. The mean age at diagnosis was 11.6 years. Twenty-three patients were males (96%). Systemic medical history included three patients with bronchial asthma, one patient with Down's syndrome, one patient with generalised skeletal malformation and one patient with gastritis. The initial uncorrected visual acuity was 20/30 or better in 93.5% of the eyes. At presentation, the tumour was unilateral in 12 cases (50%). The conjunctival mass was located on the bulbar conjunctiva in all cases. The mass was present nasally in 96% of lesions. No cases (that were tested) had an infectious aetiology. PCR demonstrated monoclonality suggestive of lymphoma in two cases; however, this did not alter the final diagnosis as BRLH per histopathological criteria and clinical course, CONCLUSIONS: All investigated cases of paediatric conjunctival BRLH had a benign clinical course with no local or systemic dissemination and a male predominance. Recurrence was rare, and in our cohort, it was not associated with malignant transformation.


Assuntos
Túnica Conjuntiva/patologia , Doenças da Túnica Conjuntiva/diagnóstico , Pseudolinfoma/diagnóstico , Adolescente , Criança , Pré-Escolar , Doenças da Túnica Conjuntiva/epidemiologia , Feminino , Seguimentos , Humanos , Incidência , Lactente , Recém-Nascido , Masculino , Pseudolinfoma/epidemiologia , Estudos Retrospectivos , Arábia Saudita/epidemiologia , Fatores de Tempo
6.
Middle East Afr J Ophthalmol ; 23(1): 139-41, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26957854

RESUMO

UNLABELLED: To report novel mutations in two Saudi children with clinical features of Leber congenital amaurosis (LCA) and Alström syndrome. CASE REPORTS: Case 1 was a child with phenotypic features of LCA including oculodigital sign, bilateral enophthalmos, nystagmus, pale disc, and retinal changes. Direct sequencing of the coding sequence of GUCY2D revealed a missense mutation affecting highly conserved position (c. 743C > T; p.S248 L). Case 2 describes a girl with marked nystagmus, photophobia, and retinal changes in both eyes with short and stubby fingers tapering at the distal phalanges. The electroretinograms were nonrecordable in each eye. She had a hearing aid in the left ear, mid-facial hypoplasia, bilateral enophthalmos, and insulin dependent diabetes. Mutation screening of candidates genes revealed a pathogenic mutation in ALMS1 gene (c. 8441C > A, p.S2814). Two novel mutations causing phenotypic LCA and Alström syndrome in Saudi patients from consanguineous families expand the genotypic spectrum of congenital retinal dystrophies.


Assuntos
Síndrome de Alstrom/genética , Guanilato Ciclase/genética , Amaurose Congênita de Leber/genética , Mutação de Sentido Incorreto , Proteínas/genética , Receptores de Superfície Celular/genética , Retina/fisiologia , Distrofias Retinianas/genética , Síndrome de Alstrom/diagnóstico , Síndrome de Alstrom/fisiopatologia , Proteínas de Ciclo Celular , Criança , Consanguinidade , Análise Mutacional de DNA , Eletrorretinografia , Feminino , Humanos , Lactente , Amaurose Congênita de Leber/diagnóstico , Amaurose Congênita de Leber/fisiopatologia , Linhagem , Distrofias Retinianas/diagnóstico , Distrofias Retinianas/fisiopatologia , Arábia Saudita
8.
Nat Genet ; 47(4): 387-92, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25706626

RESUMO

Exfoliation syndrome (XFS) is the most common recognizable cause of open-angle glaucoma worldwide. To better understand the etiology of XFS, we conducted a genome-wide association study (GWAS) of 1,484 cases and 1,188 controls from Japan and followed up the most significant findings in a further 6,901 cases and 20,727 controls from 17 countries across 6 continents. We discovered a genome-wide significant association between a new locus (CACNA1A rs4926244) and increased susceptibility to XFS (odds ratio (OR) = 1.16, P = 3.36 × 10(-11)). Although we also confirmed overwhelming association at the LOXL1 locus, the key SNP marker (LOXL1 rs4886776) demonstrated allelic reversal depending on the ancestry group (Japanese: OR(A allele) = 9.87, P = 2.13 × 10(-217); non-Japanese: OR(A allele) = 0.49, P = 2.35 × 10(-31)). Our findings represent the first genetic locus outside of LOXL1 surpassing genome-wide significance for XFS and provide insight into the biology and pathogenesis of the disease.


Assuntos
Canais de Cálcio/genética , Síndrome de Exfoliação/genética , Polimorfismo de Nucleotídeo Único , Animais , Povo Asiático/genética , Povo Asiático/estatística & dados numéricos , Estudos de Casos e Controles , Mapeamento Cromossômico , Síndrome de Exfoliação/epidemiologia , Predisposição Genética para Doença , Estudo de Associação Genômica Ampla , Glaucoma de Ângulo Aberto/epidemiologia , Glaucoma de Ângulo Aberto/genética , Células HEK293 , Células HeLa , Humanos , Japão/epidemiologia , Células MCF-7 , Camundongos , Camundongos Endogâmicos C57BL , Células Tumorais Cultivadas
9.
Mol Vis ; 15: 2464-9, 2009 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-19956407

RESUMO

PURPOSE: To catalog mutations that underlie retinitis pigmentosa (RP) in Saudi Arabia using a representative sample. METHODS: Fifty-two patients with RP were recruited and their homozygosity mapping, with or without linkage analysis, was used to suggest the causative genes followed by bidirectional sequencing. RESULTS: Mutations were identified in 94% of our study cohort, including seven that were novel. CONCLUSIONS: Homozygosity mapping is an extremely robust approach in the study of retinitis pigmentosa in the setting of high rates of consanguinity. BBS3 mutations can rarely present as nonsyndromic RP.


Assuntos
Povo Asiático/genética , Retinose Pigmentar/genética , Sequência de Aminoácidos , Sequência de Bases , Mapeamento Cromossômico , Sequência Conservada , Análise Mutacional de DNA , Feminino , Ligação Genética , Homozigoto , Humanos , Masculino , Dados de Sequência Molecular , Mutação de Sentido Incorreto/genética , Linhagem , Arábia Saudita
10.
Nat Genet ; 40(11): 1285-7, 2008 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-18836446

RESUMO

Using a positional cloning approach supported by comparative genomics, we have identified a previously unreported gene, EYS, at the RP25 locus on chromosome 6q12 commonly mutated in autosomal recessive retinitis pigmentosa. Spanning over 2 Mb, this is the largest eye-specific gene identified so far. EYS is independently disrupted in four other mammalian lineages, including that of rodents, but is well conserved from Drosophila to man and is likely to have a role in the modeling of retinal architecture.


Assuntos
Proteínas de Drosophila/química , Drosophila melanogaster/química , Proteínas do Olho/genética , Genes Recessivos , Mutação/genética , Retinose Pigmentar/genética , Homologia de Sequência de Aminoácidos , Animais , Linhagem Celular , Cromossomos Humanos Par 6/genética , Proteínas do Olho/química , Proteínas do Olho/metabolismo , Perfilação da Expressão Gênica , Regulação da Expressão Gênica , Humanos , Estrutura Terciária de Proteína , Transporte Proteico
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