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2.
Clin Ophthalmol ; 15: 41-47, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33447010

RESUMO

BACKGROUND/AIMS: Effective management of diabetic retinopathy requires multidisciplinary input. We aimed to evaluate the impact of point of care (POC) HbA1c testing as a tool to identify patients most in need of specialist diabetologist input and assess the accuracy and determinants of patients' insight into their glycaemic and blood pressure control. METHODS: Forty-nine patients with diabetic retinopathy were recruited from the eye clinic at Great Western Hospital. Patients completed a questionnaire and POC HbA1c and blood pressure values were measured. Statistical analysis was completed with SPSS v23. RESULTS: Mean age was 64.4 years, median interval since the last formal HbA1c reading was 10.2 months and the mean POC HbA1c was 64.1 mmol/mol. HbA1c significantly correlated with the degree of retinopathy. Of the patients, 81.6% had POC readings above the levels recommended by the National Institute for Health and Care Excellence, with only 16.3% having insight into this. Insight to HbA1c levels was predicted by age but not by duration of disease. Fourteen patients (33.3%) identified with high HbA1c readings were referred to secondary diabetic services and 88.8% of patients felt that the test was useful and likely to improve their diabetic control. CONCLUSION: The majority of patients had poor insight into their diabetes control, with sub-optimal treatment and follow-up. Poor insight is high in younger patients, suggesting that POC HbA1c testing is particularly important in educating younger patients who may be Type 1 diabetics with more severe disease. POC HbA1c represents a cost-effective, reproducible and clinically significant tool for the management of diabetes in an outpatient ophthalmology setting, allowing the rapid recognition of high-risk patients and appropriate referral to secondary diabetic services.

3.
Clin Ophthalmol ; 9: 1269-74, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26203216

RESUMO

PURPOSE: To evaluate the effect of repeated intravitreal ranibizumab injections for neovascular age related macular degeneration (nAMD) on the retinal nerve fiber layer (RNFL) thickness using optical coherence tomography. DESIGN: A prospective observational cohort study of patients with nAMD. METHODS: Thirty eyes of 30 patients with nAMD were selected. All patients received three ranibizumab injections and underwent scans using the fast RNFL thickness protocol (Stratus optical coherence tomography) before starting the first injection and 1 month after the third injection. The RNFL thickness measurements prior to the injections and after the third injection were used for the analysis. We also evaluated the effect of the lens status as well as the type of choroidal neovascular membrane on RNFL thickness measurements pre- and post-injection. Pre- and post-injection average and individual quadrant RNFL thickness were measured and statistically analyzed. RESULTS: The mean (± standard deviation) pre-injection RNFL thickness was 90.8±18. The mean (± standard deviation) post-injection RNFL thickness was 91.03±15. The pre- and post-injection values of the mean RNFL thickness were not statistically significant. Likewise, the pre- and post-injection values for RNFL thickness in the different quadrants were not statistically significant. There was no statistical significance for the lens status or the type of choroidal neovascular membrane on the RNFL thickness. CONCLUSION: Repeated ranibizumab injections in nAMD appear to have no harmful effect on the RNFL thickness in the short term, in spite of the proven neurotrophic effect of vascular endothelial growth factor. Nevertheless, the safety profile of ranibizumab injections in nAMD needs to be further evaluated in a large multicenter trial with special emphasis on the long-term effects on the retina and optic nerve.

4.
Bioorg Chem ; 52: 31-43, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24316885

RESUMO

Despite recent progress in antithrombotic therapy, there's still an unmet medical need for safe and orally available anticoagulants. Encouraged by the marked antithrombotic and anticoagulant activities of some coumarin derivatives, twenty-three new N-coumarinyl-4-amidinobenzamides 4a-f and 6-heterocycle substituted coumarin derivatives 5, 6a,b, 10a-e, 12a-e and 14a-d were synthesized and evaluated for their in vivo antithrombotic activity. The most active congeners were the unsubstituted amidine 4a (36.5 s), coumarinyl oxadiazole 5 (42.3 s), bis coumarinyl oxadiazole 6b (37.8 s) and coumarinyl pyrazole 10b (38.5 s) that presented prothrombin time (PT) values comparable to the reference drug warfarin (42.3 s). Furthermore, docking studies were undertaken to gain insight into the possible binding mode of these compounds with the coagulation factor Xa (FXa) binding site.


Assuntos
Anticoagulantes/farmacologia , Cumarínicos/química , Inibidores do Fator Xa , Fibrinolíticos/química , Fibrinolíticos/farmacologia , Animais , Anticoagulantes/síntese química , Anticoagulantes/química , Sítios de Ligação , Fator Xa/química , Fator Xa/metabolismo , Fibrinolíticos/síntese química , Masculino , Camundongos , Simulação de Acoplamento Molecular , Estrutura Molecular , Tempo de Protrombina , Relação Estrutura-Atividade , Varfarina/farmacologia
5.
Invest Ophthalmol Vis Sci ; 51(8): 4266-72, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20237254

RESUMO

PURPOSE: Recently, a novel gene was cloned for autosomal recessive retinitis pigmentosa (arRP), EYS, on 6q12. This study was conducted to determine the spectrum and frequency of EYS mutations in 195 unrelated patients with autosomal recessive and autosomal dominant RP (adRP). METHODS: All cases had a complete ophthalmic examination, and the clinical diagnosis of RP was based on visual acuity, fundus photography, and electroretinography findings. The DNA extracted from all participants was subjected to molecular genetic analysis entailing amplification of the coding regions and exon-intron boundaries of EYS by polymerase chain reaction, followed by direct sequencing. Bioinformatics analysis was undertaken to study the effect of the identified mutations on protein structure and function. RESULTS: Eleven novel missense, nonsense, and splice site mutations were identified within EYS in 10 unrelated arRP patients, with probable allele frequency of 11%. However, no mutations were observed in the adRP panel. In addition, 53 single-nucleotide polymorphisms (SNPs) were found, of which 12 were previously unreported. Bioinformatics analyses revealed that all mutations were highly conserved across other species and/or involved important domains on protein structure. Intrafamilial phenotypic variability was also observed in a family with double heterozygous mutations. CONCLUSIONS: This is the first report of molecular genetic analysis of EYS in a cohort of unrelated British and Chinese patients with RP. The results further the initial hypothesis that EYS is a major causative gene for recessive RP and emphasize the role of different types of mutations in disrupting the function of EYS.


Assuntos
Proteínas do Olho/genética , Genes Recessivos , Mutação , Retinose Pigmentar/genética , Adulto , Análise Mutacional de DNA , Feminino , Frequência do Gene , Humanos , Masculino , Linhagem , Reação em Cadeia da Polimerase , Polimorfismo de Nucleotídeo Único , Retinose Pigmentar/diagnóstico , Acuidade Visual/fisiologia , Adulto Jovem
6.
Br J Ophthalmol ; 94(2): 250-5, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19734134

RESUMO

AIM: To identify the underlying genetic defect in Egyptian patients with macular corneal dystrophy (MCD). METHODS: A clinical and molecular genetic study was performed on 11 patients from six families with MCD. Clinical diagnosis was confirmed by slit-lamp biomicroscopy and histopathological examination of corneal buttons following keratoplasty. The coding region of the carbohydrate sulfotransferase (CHST6) gene was amplified by polymerase chain reaction (PCR) in all affected subjects. This was followed by direct sequencing and restriction digest analyses. Enzyme-linked immunosorbent assay of antigenic keratan sulfate (KS) in patients' serum was also performed. RESULTS: Six homozygous mutations, of which three are novel, were identified within the coding region of CHST6 in six unrelated MCD families. The barely detectable level of antigenic KS in the serum of the affected individuals indicated that they all have MCD type I, including the subtype IA. CONCLUSIONS: This is the first report of a molecular genetic analysis of MCD in the Egyptian population. These data indicate the extensive allelic heterogeneity within CHST6 and further support its essential role in maintaining corneal transparency.


Assuntos
Distrofias Hereditárias da Córnea/genética , Mutação , Sequência de Aminoácidos , Árabes/genética , Biomarcadores/sangue , Distrofias Hereditárias da Córnea/sangue , Análise Mutacional de DNA/métodos , Egito , Feminino , Humanos , Sulfato de Queratano/sangue , Masculino , Dados de Sequência Molecular , Linhagem , Alinhamento de Sequência , Sulfotransferases/genética , Carboidrato Sulfotransferases
8.
Fertil Steril ; 91(3): 694-7, 2009 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-18675959

RESUMO

OBJECTIVE: To determine whether GnRHa administration before and during combination chemotherapy for breast cancer could preserve posttreatment ovarian function in young women or not. DESIGN: Prospective randomized controlled study. SETTING: Department of Obstetrics and Gynecology, Mansura University Hospital, Mansura, Egypt. PATIENT(S): Eighty patients with unilateral adenocarcinoma of the breast and with no metastasis who had undergone modified radical mastectomy or breast-conserving surgery plus full axillary lymph node dissection were included in the study. Patients were assigned randomly to receive combined GnRHa and chemotherapy or chemotherapy alone. One woman in each group dropped out. MAIN OUTCOME MEASURE(S): Return of spontaneous menstruation and ovulation. Hormonal changes (FSH, LH, E(2), P) during and after the course of treatment. RESULT(S): In the study group, 89.6% resumed menses and 69.2% resumed spontaneous ovulation within 3-8 months of termination of the GnRHa/chemotherapy cotreatment; 11.4% experienced hypergonadotrophic amenorrhoea and ovarian failure 8 months after treatment. In the control group (chemotherapy without GnRHa), 33.3% resumed menses and 25.6% resumed normal ovarian activity. The median FSH and LH concentrations, 6 months after completion of the GnRHa/chemotherapy cotreatment group, were significantly less than the control group. During the GnRHa/chemotherapy cotreatment the concentrations of FSH, LH, and P decreased to almost prepubertal levels. However, within 1-3 months after the last GnRHa injection, an increase in LH and FSH concentrations was detected, followed several weeks later in by an increase in P concentrations to within normal levels. CONCLUSION(S): GnRHa administration before and during combination chemotherapy for breast cancer may preserve posttreatment ovarian function in women <40 years. Long-term studies are required.


Assuntos
Adenocarcinoma/tratamento farmacológico , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Neoplasias da Mama/tratamento farmacológico , Fármacos para a Fertilidade Feminina/administração & dosagem , Hormônio Liberador de Gonadotropina/agonistas , Gosserrelina/administração & dosagem , Infertilidade Feminina/prevenção & controle , Ovário/efeitos dos fármacos , Adenocarcinoma/cirurgia , Adulto , Amenorreia/induzido quimicamente , Amenorreia/prevenção & controle , Neoplasias da Mama/cirurgia , Quimioterapia Adjuvante , Esquema de Medicação , Estradiol/sangue , Feminino , Hormônio Foliculoestimulante Humano/sangue , Humanos , Infertilidade Feminina/induzido quimicamente , Infertilidade Feminina/fisiopatologia , Hormônio Luteinizante/sangue , Excisão de Linfonodo , Mastectomia , Menstruação/efeitos dos fármacos , Ovário/fisiopatologia , Ovulação/efeitos dos fármacos , Insuficiência Ovariana Primária/induzido quimicamente , Insuficiência Ovariana Primária/prevenção & controle , Progesterona/sangue , Estudos Prospectivos , Fatores de Tempo , Resultado do Tratamento
9.
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
10.
Curr Eye Res ; 33(8): 693-9, 2008 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18696345

RESUMO

PURPOSE: To evaluate macular thickness measurements in normal subjects from British origin, to assess interocular asymmetry using optical coherence tomography (OCT) and to establish standard values for macular and foveal thickness. METHODS: Two hundred eyes of 100 normal individuals underwent serial scans using fast macular thickness map protocol in the Stratus OCT version 3.51, with foveal fixation. Minimum foveal thickness (MFT), central 1 mm average foveal thickness (AFT), total foveal volume (TFV) and total macular volume (TMV at 6 mm) of both eyes were assessed. The interocular asymmetry was measured and statistically analyzed. RESULTS: The mean +/- SD (N = 200) was 173 +/- 23 microm for MFT and 203 +/- 24 microm for AFT. The mean difference +/- SD between the two eyes was (3.5 +/- 14.5 microm at p = 0.17) for MFT, (6.4 +/- 14.7 microm at p = 0.06) for AFT, (0.007 mm3 +/- 0.007 at p = 0.06) for TFV and (0.19 +/- 0.35 at p = 0.07) for TMV. CONCLUSION: Our study provides a normative database for macular thickness and volume parameters in normal British individuals using Stratus OCT. The MFT, AFT, TMV and TFV measurements were not statistically significant between the two eyes. Hence, the interocular symmetry should be considered on interpretation of macular thickness values especially in cases of uniocular or asymmetrical macular involvement.


Assuntos
Macula Lutea/anatomia & histologia , Tomografia de Coerência Óptica , Adulto , Idoso , Idoso de 80 Anos ou mais , Anatomia Transversal , Pesos e Medidas Corporais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Valores de Referência , Reino Unido
11.
Mol Vis ; 13: 1887-91, 2007 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-17960127

RESUMO

PURPOSE: To evaluate the role of the visual system homeobox gene 1 (VSX1) in the pathogenesis of familial keratoconus. METHODS: Families with two or more individuals with keratoconus were recruited and their members examined. The coding region and intron-exon junctions of the VSX1 gene were sequenced in affected individuals. In cases where there were possible pathogenic changes, segregation within the pedigree was analyzed. Meta analysis of reports on an association of p.D144E change with keratoconus phenotype was performed. RESULTS: Probands from a panel of 85 apparently unrelated keratoconus families were included. Eleven sequence variants were observed, including the previously reported c.432C>G (p.D144E) change and two novel intronic single nucleotide polymorphisms. However, these three changes did not cosegregate with the disease phenotype. CONCLUSIONS: We excluded the c.432C>G sequence alteration as the direct cause of the disease. Lack of possibly pathogenic VSX1 sequence variants in the familial panel suggests that involvement of this gene in the pathogenesis of keratoconus is likely to be confined to a small number of pedigrees, at least in the population studied.


Assuntos
Proteínas do Olho/genética , Variação Genética , Proteínas de Homeodomínio/genética , Ceratocone/genética , Adulto , Ácido Aspártico , Feminino , Ácido Glutâmico , Humanos , Masculino , Pessoa de Meia-Idade , Linhagem , Polimorfismo de Nucleotídeo Único
12.
Hum Mutat ; 28(5): 522-3, 2007 May.
Artigo em Inglês | MEDLINE | ID: mdl-17397048

RESUMO

Autosomal recessive congenital hereditary endothelial dystrophy (CHED2) is a severe and rare corneal disorder that presents at birth or shortly thereafter, characterized by corneal opacification and nystagmus. Recently the gene for CHED2 was identified and seven different mutations in the SLC4A11 gene were reported. Here, we report seven novel mutations and two previously identified mutations in families from India and the United Kingdom with recessive CHED. The novel changes include two nonsense (p.Trp240X; p.Gln800X) three missense (p.Glu143Lys; p.Cys386Arg; p.Arg755Trp) and two splice site mutations (c.2240+1G>A; c.2437-1G>A). Interestingly, the c.2398C>T (p.Gln800X) and c.2437-1G>A identified in two affected siblings represent the first compound heterozygous mutations in the SLC4A11 gene.


Assuntos
Proteínas de Transporte de Ânions/genética , Antiporters/genética , Doenças da Córnea/genética , Genes Recessivos , Mutação , Triagem de Portadores Genéticos , Humanos , Índia , Estados Unidos
13.
J Glaucoma ; 16(1): 104-11, 2007 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17224759

RESUMO

PURPOSE: To undertake mutation screening of cytochrome P4501B1 (CYP1B1, OMIM 601771) and myocilin (MYOC, OMIM 601652) genes in Egyptian and Saudi Arabian patients with primary congenital glaucoma (PCG). PATIENTS AND METHODS: A clinical and molecular genetic study was performed on 11 Egyptian and Saudi Arabian patients with PCG. Clinical diagnosis was confirmed by slit lamp biomicroscopy, gonioscopy, measurement of intraocular pressure, and corneal diameter. The coding regions of CYP1B1 and MYOC genes were amplified by polymerase chain reaction for all affected subjects. Direct sequence analysis was performed to search for sequence alterations. Haplotype analysis and genotype/phenotype correlation were carried out. RESULTS: Three CYP1B1 mutations were identified in 5 PCG patients (45.4%) of which 2 were novel (homozygous E173K and heterozygous N498D) and the third (G61E) had previously been reported. In addition 10 single nucleotide polymorphisms were identified in CYP1B1 and MYOC genes of which 2 were novel. However, no pathologic changes in either of the genes were detected in the remaining 6 patients. CONCLUSIONS: This is the first report of molecular genetic analysis of PCG in the Egyptian population in which 2 novel mutations have been identified. It is possible that these mutations are specific to this population and may lead to alterations in the protein structure encoded by the gene. Patients with no mutations in the screened genes may have mutations in genes yet to be identified.


Assuntos
Sistema Enzimático do Citocromo P-450/genética , Proteínas do Citoesqueleto/genética , Proteínas do Olho/genética , Glaucoma/genética , Glicoproteínas/genética , Mutação , Idade de Início , Sequência de Aminoácidos , Hidrocarboneto de Aril Hidroxilases , Criança , Pré-Escolar , Consanguinidade , Citocromo P-450 CYP1B1 , Análise Mutacional de DNA , Egito/epidemiologia , Feminino , Glaucoma/congênito , Glaucoma/etnologia , Gonioscopia , Haplótipos , Humanos , Lactente , Pressão Intraocular , Masculino , Biologia Molecular , Dados de Sequência Molecular , Linhagem , Reação em Cadeia da Polimerase , Arábia Saudita/epidemiologia
14.
Curr Eye Res ; 31(5): 409-13, 2006 May.
Artigo em Inglês | MEDLINE | ID: mdl-16714232

RESUMO

PURPOSE: To evaluate whether the measurement of retinal nerve fiber layer (RNFL) thickness using optical coherence tomography (OCT) changes after cataract surgery. METHODS: This prospective, randomized, observational, cross-sectional clinical study included 24 eyes of 24 patients who underwent phacoemusification with implant. All patients had no preexisting retinal or optic nerve pathology or other media opacities that might influence the RNFL thickness. The classification and the grading of cataract were based on the Lens Opacities Classification System III (LOCS III). All eyes were scanned immediately before cataract surgery with OCT using Fast RNFL program. All eyes had circular scans around the optic disk with a diameter of 3.4 mm. The OCT was repeated 4 weeks after surgery when the patients returned for postoperative check using the same programme. RESULTS: The mean preoperative RNFL thickness was 84.9 +/- 16.5. The postoperative mean RNFL thickness was 93.0 +/- 17.6. The pre-and postoperative values of the mean RNFL and signal/noise ratio (SNR) are statistically significant (P < 0.05). CONCLUSIONS: Lens opacities may affect the image quality of OCT scans used to measure RNFL thickness as indicated by preoperative low SNR. Cataract extraction results in an apparent increase of the RNFL thickness.


Assuntos
Catarata/complicações , Fibras Nervosas/patologia , Nervo Óptico/patologia , Facoemulsificação , Células Ganglionares da Retina/patologia , Tomografia de Coerência Óptica/métodos , Idoso , Idoso de 80 Anos ou mais , Catarata/classificação , Estudos Transversais , Feminino , Humanos , Implante de Lente Intraocular , Masculino , Pessoa de Meia-Idade , Cuidados Pós-Operatórios , Cuidados Pré-Operatórios , Estudos Prospectivos
15.
Ophthalmic Res ; 38(1): 19-23, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16192744

RESUMO

To identify the disease gene in 6 Spanish families with autosomal recessive retinitis pigmentosa linked to the RP25 locus, mutation screening of 4 candidate genes, KHDRBS2, PTP4A1, KIAA1411 and OGFRL1, was undertaken based on their expression or functional relevance to the retina. Twenty-six single nucleotide polymorphisms were identified, of which 14 were novel. Even though no pathological mutations were detected, these genes however remain as good candidates for other retinal degenerations mapping to the same chromosomal region.


Assuntos
Proteínas de Ciclo Celular/genética , Proteínas do Olho/genética , Genes Recessivos , Proteínas Imediatamente Precoces/genética , Proteínas de Neoplasias/genética , Proteínas Tirosina Fosfatases/genética , Proteínas de Ligação a RNA/genética , Retinose Pigmentar/genética , Análise Mutacional de DNA , Ligação Genética , Humanos , Proteínas de Membrana , Polimorfismo de Nucleotídeo Único
16.
Curr Eye Res ; 30(12): 1081-7, 2005 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-16354621

RESUMO

PURPOSE: To identify the disease gene in five Spanish families with autosomal recessive retinitis pigmentosa (arRP) linked to the RP25 locus. Two candidate genes, EEF1A1 and IMPG1, were selected from the region between D6S280 and D6S1644 markers where the families are linked. The genes were selected as good candidates on the basis of their function, tissue expression pattern, and/or genetic data. METHODS: A molecular genetic study was performed on DNA extracted from one parent and one affected member of each studied family. The coding exons, splice sites, and the 5' UTR of the genes were amplified by polymerase chain reaction (PCR). For mutation detection, direct sequence analysis was performed using the ABI 3100 automated sequencer. Segregation of an IMPG1 single nucleotide polymorphism (SNP) in all the families studied was analyzed by restriction enzyme digest of the amplified gene fragments. RESULTS: In total, 15 SNPs were identified of which 7 were novel. Of the identified SNPs, one was insertion, two were deletions, five were intronic, six were missense, and one was located in the 5' UTR. These changes, however, were also identified in unaffected members of the families and/or 50 control Caucasians. The examined known IMPG1 SNP was not segregating with the disease phenotype but was correlating with the genetic data in all families studied. CONCLUSIONS: Our results indicate that neither EEF1A1 nor IMPG1 could be responsible for RP25 in the studied families due to absence of any pathogenic variants. However, it is important to notice that the methodology used in this study cannot detect larger deletions that lie outside the screened regions or primer site mutations that exist in the heterozygous state. A role of both genes in other inherited forms of RP and/or retinal degenerations needs to be elucidated.


Assuntos
Proteínas da Matriz Extracelular/genética , Proteínas do Olho/genética , Genes Recessivos , Mutação , Proteínas Oncogênicas/genética , Proteoglicanas/genética , Retinose Pigmentar/genética , Mapeamento Cromossômico , Consanguinidade , Análise Mutacional de DNA , Feminino , Marcadores Genéticos , Humanos , Masculino , Biologia Molecular , Linhagem , Fator 1 de Elongação de Peptídeos , Reação em Cadeia da Polimerase , Polimorfismo de Nucleotídeo Único
17.
Ophthalmic Res ; 37(6): 310-7, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-16118514

RESUMO

AIMS: To identify the underlying mutations in our British families and sporadic patients with different types of corneal dystrophies (CDs) and to establish a phenotype-genotype correlation. METHODS: Twenty-nine patients, 9 sporadic and 20 patients from 7 families were subjected to both clinical and genetic examination. Slit lamp examination was performed for all patients who participated in the study to assess their corneal phenotype. Genomic DNA was extracted from 10 ml venous blood, and the BIGH3 gene was amplified exon by exon to perform heteroduplex analysis. Exons that displayed double bands were then analysed by direct bi-directional sequencing and restriction digest analyses. RESULTS: Clinically our patients showed three distinct phenotypes of CD: 16 with Thiel-Behnke corneal dystrophy or corneal dystrophy of Bowman layer type 2 (CDB2), 8 with granular CD (GCD), and 5 with lattice CD type I (LCDI). Three different missense mutations have been detected in the coding region of BIGH3 gene, R555Q, in 16 CDB2 patients, R555W in 8 GCD patients, and R124C in 5 LCDI patients. These mutations were the same as to those previously reported in patients from other ethnic origins. Also,we identified seven nucleotide substitutions that did not change the amino acid sequence of the encoded protein of which four were novel. CONCLUSIONS: In our patients of British origin, each phenotype of CD has been linked to a particular point mutation of the BIGH3 gene. Our study also highlights the importance of codons 124 and 555 as mutation hot spots in the BIGH3 gene in the British population.


Assuntos
Distrofias Hereditárias da Córnea/genética , Substância Própria/patologia , Proteínas da Matriz Extracelular/genética , Mutação , Fator de Crescimento Transformador beta/genética , Distrofias Hereditárias da Córnea/patologia , Análise Mutacional de DNA , Feminino , Genes Dominantes , Genótipo , Humanos , Masculino , Biologia Molecular , Linhagem , Fenótipo , Reação em Cadeia da Polimerase , Reino Unido
18.
Am J Ophthalmol ; 139(1): 192-3, 2005 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-15652851

RESUMO

PURPOSE: To identify the underlying mutations in two unrelated British families with macular corneal dystrophy (MCD) by screening the carbohydrate sulfotransferase (CHST6) gene. DESIGN: Case reports and results of DNA analysis. METHODS: Two subjects from two British families with MCD were studied. The genetic status of CHST6 was determined for all members of these MCD families. In addition, sulfated keratan sulfate (KS) assay from the probands was also undertaken. CHST6 gene was amplified by polymerase chain reaction (PCR). The PCR products were analyzed by sequencing and restriction digestion. Enzyme-linked immunosorbent assay (ELISA) was performed to assess KS presence in serum. RESULTS: Four compound heterozygous mutations were identified, three of which are novel. The ELISA showed that the probands were of MCD type I. CONCLUSIONS: These novel mutations are expected to result in loss of CHST6 function, which would account for the MCD phenotype.


Assuntos
Códon sem Sentido , Distrofias Hereditárias da Córnea/genética , Mutação de Sentido Incorreto , Sulfotransferases/genética , Adulto , Distrofias Hereditárias da Córnea/sangue , Análise Mutacional de DNA , Ensaio de Imunoadsorção Enzimática , Humanos , Sulfato de Queratano/sangue , Fenótipo , Reação em Cadeia da Polimerase , Carboidrato Sulfotransferases
19.
Invest Ophthalmol Vis Sci ; 43(2): 377-82, 2002 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11818380

RESUMO

PURPOSE: Macular corneal dystrophy (MCD) is a rare corneal dystrophy that is characterized by abnormal deposits in the corneal stroma, keratocytes, Descemet's membrane, and endothelium, accompanied by progressive clouding. It has been classified into three immunophenotypes--MCD types I, IA, and II--according to the serum level of sulfated keratan sulfate (KS) and immunoreactivity of the corneal tissue. Recently, mutations in a new carbohydrate sulfotransferase gene (CHST6) encoding corneal glucosamine N-acetyl-6-sulfotransferase (C-GlcNac-6-ST) have been identified as the cause of MCD. Mutation screening of the CHST6 gene has been undertaken to identify the underlying mutations in five unrelated British families with MCD. METHODS: DNA was extracted from venous blood obtained from all participants, and the coding region of CHST6 was amplified by polymerase chain reaction (PCR). The PCR products were analyzed by direct sequencing and restriction enzyme digestion. Enzyme-linked immunosorbent assay (ELISA) was performed to assess the presence of KS in serum from the probands of MCD-affected families participating in the study. RESULTS: Six novel missense mutations--four homozygous and two compound heterozygous--were identified in the CHST6 gene. The ELISA showed that the disease in all patients participating in the study was of MCD type I, including the subtype IA. CONCLUSIONS: These novel mutations are thought to result in loss of corneal sulfotransferase function, which would account for the MCD phenotype.


Assuntos
Córnea/enzimologia , Distrofias Hereditárias da Córnea/genética , Mutação , Sulfotransferases/genética , Sequência de Aminoácidos , Sequência de Bases , Córnea/patologia , Distrofias Hereditárias da Córnea/enzimologia , Distrofias Hereditárias da Córnea/patologia , Análise Mutacional de DNA , Primers do DNA/química , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Sulfato de Queratano/sangue , Masculino , Dados de Sequência Molecular , Linhagem , Reação em Cadeia da Polimerase , Carboidrato Sulfotransferases
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