RESUMO
A strain named as Pseudomonas aeruginosa 2016NX1, which could produce phenazine and cereusitin, was isolated from the root of Millettia specisoa. Phenazines were extracted, isolated and purified by chloroform, thin-layer chromatography, column chromatography and high-performance liquid chromatography. Then the purified materials were identified by analysis of nuclear magnetic resonance. The major yellow component is 1-hydroxyphenazine and the minor blue component is cereusitin A. The tests of antimicrobial activity of yellow component showed that the growth of several common plant pathogenic fungi and bacteria (such as Cochliobolus miyabeanus, Diaporthe citri, Salmonella sp., Klebsiella oxytoca) could be strongly inhibited. This study suggested that Pseudomonas aeruginosa strain 2016NX1 had a significant potential for biological control of phytopathogenic fungi. SIGNIFICANCE AND IMPACT OF THE STUDY: In this study, one bioactive substance from Pseudomonas aeruginosa 2016NX1 was identified and its antimicrobial activity was verified. This study demonstrated that one bioactive substance from P. aeruginosa can strongly inhibit the growth of plant pathogenic fungi and bacteria. This study suggested that P. aeruginosa strain 2016NX1 has a significant potential for biological control of phytopathogenic fungi.
Assuntos
Anti-Infecciosos/farmacologia , Ascomicetos/efeitos dos fármacos , Klebsiella oxytoca/efeitos dos fármacos , Fenazinas/farmacologia , Pseudomonas aeruginosa/metabolismo , Salmonella/efeitos dos fármacos , Anti-Infecciosos/metabolismo , Antibiose/fisiologia , Ascomicetos/crescimento & desenvolvimento , Bipolaris , Klebsiella oxytoca/crescimento & desenvolvimento , Millettia/microbiologia , Fenazinas/metabolismo , Pseudomonas aeruginosa/isolamento & purificação , Salmonella/crescimento & desenvolvimentoAssuntos
Povo Asiático/genética , Glaucoma de Ângulo Aberto/genética , Caveolina 1/genética , Caveolina 2/genética , Inibidor de Quinase Dependente de Ciclina p15/genética , Feminino , Variação Genética , Proteínas de Homeodomínio/genética , Hong Kong , Humanos , Masculino , Polimorfismo de Nucleotídeo Único , Transativadores/genética , Pesquisa Translacional BiomédicaRESUMO
AIMS/HYPOTHESIS: Although skeletal muscle insulin resistance has been associated with activation of c-Jun N-terminal kinase (JNK), whether increased JNK activity causes insulin resistance in this organ is not clear. In this study we examined the metabolic consequences of isolated JNK phosphorylation in muscle tissue. METHODS: Plasmids containing genes encoding a wild-type JNK1 (WT-JNK) or a JNK1/JNKK2 fusion protein (rendering JNK constitutively active; CA-Jnk) were electroporated into one tibialis anterior (TA) muscle of C57Bl/6 mice, with the contralateral TA injected with an empty vector (CON) to serve as a within-animal control. RESULTS: Overproduction of WT-JNK resulted in a modest (~25%) increase in phosphorylation (Thr(183)/Tyr(185)) of JNK, but no differences were observed in Ser(307) phosphorylation of insulin receptor substrate 1 (IRS-1) or total IRS-1 protein, nor in insulin-stimulated glucose clearance into the TA muscle when comparing WT-JNK with CON. By contrast, overexpression of CA-Jnk, which markedly increased the phosphorylation of CA-JNK, also increased serine phosphorylation of IRS-1, markedly decreased total IRS-1 protein, and decreased insulin-stimulated phosphorylation of the insulin receptor (Tyr(1361)) and phosphorylation of Akt at (Ser(473) and Thr(308)) compared with CON. Moreover, overexpression of CA-Jnk decreased insulin-stimulated glucose clearance into the TA muscle compared with CON and these effects were observed without changes in intramuscular lipid species. CONCLUSIONS/INTERPRETATION: Constitutive activation of JNK in skeletal muscle impairs insulin signalling at the level of IRS-1 and Akt, a process which results in the disruption of normal glucose clearance into the muscle.
Assuntos
Resistência à Insulina/fisiologia , Proteínas Quinases JNK Ativadas por Mitógeno/metabolismo , Músculo Esquelético/metabolismo , Animais , Proteínas Substratos do Receptor de Insulina/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Modelos Animais , Fosforilação , Proteínas Proto-Oncogênicas c-akt/metabolismoRESUMO
Persistence of protective immunity for SARS-CoV-2 is important against reinfection. Knowledge on SARS-CoV-2 immunity in pediatric patients is currently lacking. We opted to assess the SARS-CoV-2 adaptive immunity in recovered children and adolescents, addressing the pediatrics specific immunity towards COVID-19. Two independent assays were performed to investigate humoral and cellular immunological memory in pediatric convalescent COVID-19 patients. Specifically, RBD IgG, CD4+, and CD8+ T cell responses were identified and quantified in recovered children and adolescents. SARS-CoV-2-specific RBD IgG detected in recovered patients had a half-life of 121.6 days and estimated duration of 7.9 months compared with baseline levels in controls. The specific T cell response was shown to be independent of days after diagnosis. Both CD4+ and CD8+ T cells showed robust responses not only to spike (S) peptides (a main target of vaccine platforms) but were also similarly activated when stimulated by membrane (M) and nuclear (N) peptides. Importantly, we found the differences in the adaptive responses were correlated with the age of the recovered patients. The CD4+ T cell response to SARS-CoV-2 S peptide in children aged <12 years correlated with higher SARS-CoV-2 RBD IgG levels, suggesting the importance of a T cell-dependent humoral response in younger children under 12 years. Both cellular and humoral immunity against SARS-CoV-2 infections can be induced in pediatric patients. Our important findings provide fundamental knowledge on the immune memory responses to SARS-CoV-2 in recovered pediatric patients.
Assuntos
Imunidade Adaptativa/imunologia , Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/imunologia , COVID-19/imunologia , Convalescença , SARS-CoV-2/imunologia , Adolescente , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/metabolismo , Linfócitos T CD4-Positivos/virologia , Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/metabolismo , Linfócitos T CD8-Positivos/virologia , COVID-19/virologia , Criança , Pré-Escolar , Feminino , Humanos , Imunidade Humoral/imunologia , Imunoglobulina G/imunologia , Masculino , SARS-CoV-2/metabolismo , SARS-CoV-2/fisiologia , Glicoproteína da Espícula de Coronavírus/imunologia , Glicoproteína da Espícula de Coronavírus/metabolismoRESUMO
Human tear fluid is a complex mixture of aqueous lipids, proteins, enzymes, and other biochemical and cellular elements. By conventional comparative proteomic approaches, we investigated the proteome in human tear fluid and compared the tear protein profile of normal control subjects with that of patients suffering from the ocular inflammatory disease vernal keratoconjunctivitis (VKC). Collected tear samples were directed to two-dimensional polyacrylamide gel electrophoresis protein separation and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry peptide identification. Six differentially expressed proteins-interleukin 4, phospholipase A2, albumin, lactoferrin, hemopexin, and lipocalin-were displayed. Hemopexin had not been reported previously in tear film. Enzyme-linked immunosorbent assay confirmed that hemopexin concentrations were significantly higher in VKC tear samples and increased with disease stages. The results implied clinical interest of hemopexin in the tear proteome and eye diseases.
Assuntos
Eletroforese em Gel Bidimensional/métodos , Hemopexina/análise , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Lágrimas/metabolismo , Conjuntivite Alérgica/metabolismo , Ensaio de Imunoadsorção Enzimática/métodos , Humanos , ProteomaRESUMO
Importance: Microvascular abnormalities in amblyopia are becoming evident with high-resolution imaging, such as optical coherence tomography angiography (OCT-A); however, to our knowledge, the clinical significance and use of these findings are unknown. Objective: To assess changes in quantitative OCT-A metrics in amblyopic eyes and explore their association with visual acuity in children. Design, Setting, and Participants: This population-based nested case-control study included children aged 6 to 8 years who were consecutively recruited between January 2016 and July 2017 from the population-based Hong Kong Children Eye Study (HKCES) at the Chinese University of Hong Kong Eye Centre. All participants underwent OCT-A with a swept-source OCT and detailed ophthalmic investigations. Macular microvasculature of the superficial capillary plexus was quantified by a customized automated image analysis program. A multivariable linear regression was conducted to evaluate the differences in OCT-A metrics between amblyopic and nonamblyopic eyes after adjustment for all known confounders. Data analysis was conducted from September to November 2018. Main Outcomes and Measures: Differences in OCT-A metric (foveal avascular zone [FAZ]) area, FAZ circularity, vessel density, vessel diameter index, and fractal dimension between amblyopic and nonamblyopic eyes. Results: There were 30 participants with amblyopia (mean [SD] age, 7.57 [1.2] years; 16 girls [53.3%]) and 1045 controls (mean [SD] age, 7.65 [1.0] years; 580 girls [55.5%]) in this cohort. Compared with control eyes, amblyopic eyes had decreased FAZ circularity (-0.058; 95% CI, -0.096 to -0.021, P = .002), decreased fractal dimension (-0.014; 95% CI, -0.024 to -0.003; P = .01), and increased vessel diameter index (0.002; 95% CI, 0.002 to 0.003; P < .001). A difference was not identified between FAZ area and vessel density. LogMAR visual acuity was associated with FAZ circularity (sß, -0.133; P < .001) and vessel diameter index (sß, 0.097; P = .001) but not with vessel density nor FAZ area. Conclusions and Relevance: The results of this population-based study in children supports the presence of macular microvascular abnormalities in amblyopic eyes. Such changes as measured by OCT-A metrics are associated with visual acuity, inferring retinal involvement in the development of amblyopia and suggesting a potential role of quantitative OCT-A metrics in the diagnosis and recognition of amblyopia.
Assuntos
Ambliopia/diagnóstico , Angiofluoresceinografia , Macula Lutea/irrigação sanguínea , Doenças Retinianas/diagnóstico , Vasos Retinianos/patologia , Tomografia de Coerência Óptica , Transtornos da Visão/diagnóstico , Ambliopia/fisiopatologia , Benchmarking , Estudos de Casos e Controles , Criança , Feminino , Hong Kong , Humanos , Masculino , Microvasos , Doenças Retinianas/fisiopatologia , Vasos Retinianos/diagnóstico por imagem , Transtornos da Visão/fisiopatologia , Acuidade Visual/fisiologiaRESUMO
Intraocular pressure (IOP) elevation has often been used as an experimental model to study mechanisms underlying retinal ganglion cell (RGC) death associated with ocular ischemic injury and glaucoma. The aim of the present study, using both in vitro and in vivo approaches, was to investigate the role of phosphatidylinositol 3-kinase (PI3K)/akt pathway in RGC viability in normal rats and rats following transient IOP elevation. For in vivo studies, pathway inhibitors were administered intravitreally on days 3, 9, and 15 post-2-h IOP elevation at 110 mm Hg. Toward the end of the 3-week examination period, the fluorescent dye Fluorogold was used to retrogradely label surviving RGCs. In order to examine the role of macrophages that were recruited into the eye following the pathway inhibition, clodronate liposomes were used to deplete phagocytic cells in the eye. PI3K/akt pathway activity and location in the retina were examined using Western blot and immunohistochemistry, respectively. Here we showed that PI3K/akt inhibitors 2-(4-morpholinyl)-8-phenyl-1(4H)-benzopyran-4-one hydrochloride (LY294002) and KY12420 at low concentrations (2 microM or 20 microM) did not influence RGC survival but caused RGC loss at high concentration (200 muM) in retinal explants derived from intact rats. In contrast, both LY294002 and KY12420 at 20 microM led to RGC loss in retinal explants derived from IOP-elevated eyes. A detrimental action of phagocytic cells on RGC survival was also seen in these retinas. In vivo results confirmed the detrimental actions of PI3K/akt inhibition and macrophages on RGC survival in IOP-elevated, but not intact eyes even with high concentration of LY294002. Low level of PI3K/akt activity was detected in the ganglion cell layer (GCL) in intact retina. Acute IOP elevation activated PI3K/akt pathway in the inner nuclear layer and GCL including RGCs. This study thus demonstrates that PI3K/akt pathway mediates RGC survival after IOP elevation but not under normal condition.
Assuntos
Hipertensão Ocular/enzimologia , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Células Ganglionares da Retina/enzimologia , Animais , Sobrevivência Celular/fisiologia , Quimiotaxia de Leucócito/efeitos dos fármacos , Quimiotaxia de Leucócito/fisiologia , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Inibidores Enzimáticos/farmacologia , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Hipertensão Ocular/patologia , Hipertensão Ocular/fisiopatologia , Inibidores de Fosfoinositídeo-3 Quinase , Proteínas Proto-Oncogênicas c-akt/antagonistas & inibidores , Ratos , Ratos Sprague-Dawley , Células Ganglionares da Retina/patologia , Transdução de Sinais/fisiologia , EstilbamidinasRESUMO
We report the first use in Hong Kong of molecular techniques to screen prenatally for retinoblastoma and review 17 cases of retinoblastoma seen at the Hong Kong Eye Hospital from 2001 to 2006. A pregnant couple whose first child had retinoblastoma requested prenatal screening for retinoblastoma during their second pregnancy in 2000. Whole RB1 coding gene sequencing was performed on peripheral blood cells taken from family members and cultured amniocytes collected from the foetus during the 14th week of gestation. No RB1 gene mutations were found in the amniocyte samples and at birth the baby had no evidence of ocular tumours. During 5 years of follow-up the child remained healthy with intact visual function. Prenatal diagnosis of retinoblastoma alleviates parental stress and improves the perinatal care of affected family members.
Assuntos
Testes Genéticos , Diagnóstico Pré-Natal , Neoplasias da Retina/genética , Retinoblastoma/genética , Adulto , Feminino , Hong Kong , Humanos , Masculino , Linhagem , Reação em Cadeia da Polimerase , Gravidez , Neoplasias da Retina/diagnóstico , Retinoblastoma/diagnóstico , Proteína do Retinoblastoma/genéticaRESUMO
To complement cDNA libraries from the human eye at early gestation and to discover candidate genes associated with early ocular development, we used freshly dissected human eyeballs from week 9-14 of gestation to construct the early human fetal eye cDNA library. A total of 15,809 clones were isolated and sequenced from the unamplified and unnormalized library. We screened 11,246 good-quality ESTs, leading to the identification of 5,534 nonredundant clusters. Among them, 4,010 (72%) genes matched in the human protein database (Ensembl). The remaining 28% (1,524) corresponded to potentially novel or previously unidentified ESTs. We used BLASTX to compare our EST data with eight organisms and found common expression of a high portion of genes: Caenorhabditis briggsae (26%), Caenorhabditis elegans (27%), Anopheles gambiae (37%), Drosophila melanogaster (32%), Danio rerio (42%), Fugu rubripes (49%), Rattus norvegicusvalitus (52%), and Mus musculus (59%). Nevertheless, 48% (2,680 of 5,534) of the genes expressed in the early developing eye were not shared with current NEIBank human eye cDNA data. In addition, eight known retinal disease genes existed in our ESTs. Among them, six (COL11A1, BBS5, PDE6B, OAT, VMD2, and PGK1) were conserved among the genomes of other organisms, indicating that our annotated EST set provides not only a valuable resource for gene discovery and functional genomic analysis but also for phylogenetic analysis. Our foremost early gestation human eye cDNA library could provide detailed comparisons across species to identify physiological functions of genes and to elucidate evolutionary mechanisms.
Assuntos
Etiquetas de Sequências Expressas , Proteínas do Olho/genética , Olho/metabolismo , Regulação da Expressão Gênica no Desenvolvimento , Animais , Mapeamento Cromossômico , Análise por Conglomerados , Bases de Dados Genéticas , Olho/embriologia , Proteínas do Olho/metabolismo , Feminino , Feto/metabolismo , Biblioteca Gênica , Idade Gestacional , Proteínas de Choque Térmico HSP40/genética , Proteínas de Choque Térmico HSP40/metabolismo , Humanos , Oxirredutases Intramoleculares/genética , Oxirredutases Intramoleculares/metabolismo , Gravidez , RNA Mensageiro/metabolismo , Doenças Retinianas/genética , Homologia de Sequência do Ácido Nucleico , Especificidade da EspécieRESUMO
OBJECTIVES: Our aim was to utilize publicly available and proprietary sources to discover candidate genes important for ocular development. DESIGN AND METHODS: The collated information on our 5092 non-redundant clusters was grouped and functional annotation was conducted using gene ontology (FatiGO) for categorizing them with respect to molecular function. The web-based viewer technological platform (H-InvDB) was employed for transcription analyses of in-house high quality fetal eye Expressed Sequence Tags (ESTs). Eye-specific ESTs were also analyzed across species by using EMBEST. RESULTS: According to adult eye cDNA libraries, nucleic acid binding and cell structure/cytoskeletal protein genes were the most abundant among the ESTs of fetal eyes. Using cDNA assembly in H-InvDB, 20 (80%) of the 25 most commonly expressed genes in the human eye are also expressed in extraocular tissues. The crystalline gamma S gene is highly expressed in the eye, but not in other tissues. We used EMBEST to compare human fetal eye and octopus eye ESTs and the expression similarity was low (1.6%). This indicated that our fetal eye library contains genes necessary for the developmental process and biological function of the eye, which may not be expressed in the fully developed octopus eyes. The human fetal eye cDNA library also contained highly abundant eye tissue genes, including alphaA-crystallin, eukaryotic translation elongation factor 1 alpha 1 (EEF1A1), bestrophin (VMD2), cystatin C, and transforming growth factor, beta-induced (BIGH3). CONCLUSIONS: Our annotated EST set provides a valuable resource for gene discovery and functional genomic analysis. This display will help to appreciate the strengths and weaknesses of the different technological platforms, so that in future studies the maximum amount of beneficial information can be derived from the appropriate use of each method.
Assuntos
Bases de Dados Genéticas , Olho/metabolismo , Genes Controladores do Desenvolvimento/genética , Transcrição Gênica/genética , Animais , Células Clonais , Etiquetas de Sequências Expressas , Feminino , Feto/metabolismo , Regulação da Expressão Gênica no Desenvolvimento/genética , Biblioteca Gênica , Humanos , Octopodiformes/genética , Gravidez , Software , Estatística como AssuntoRESUMO
Retinitis pigmentosa (RP) is a group of inherited progressive retinal diseases affecting about 1 in 3500 people worldwide. So far, there is no prevention or cure, with permanent visual loss or even blindness the ultimate consequence usually after midlife. The genetics of RP are complex. It can be sporadic, autosomal dominant, autosomal recessive, or X-linked. Thirty-two genes are known to be associated with RP, sometimes the same gene gets involved in different inheritance traits. Some RP cases have a digenic cause. About 60% RP cases still have no known genetic cause. A large number of mutations cause RP, and they can be deletions, insertions, or substitutions that cause missense mutations or truncations. The RHO, RP1, and RPGR genes contribute the greatest number of known mutations causative of RP. But there is no single mutation that alone accounts for more than 10% of unrelated patients. Genetic testing for RP therefore requires screening for a group of genes. High-throughput and automated sequence detection technologies are essential. Due to the complexity in phenotype and genetics, and the fact that RP is untreatable, genetic testing for presymptomatic diagnosis of RP is controversial. Meanwhile, new genes are still to be identified, mostly by family linkage and sib-pair analysis. Research on gene therapy for RP requires information on gene mutations causative of RP.
Assuntos
Mutação/fisiologia , Retinose Pigmentar/genética , Retinose Pigmentar/terapia , Proteínas do Olho/genética , Terapia Genética , Humanos , Proteínas Associadas aos Microtúbulos , Retinose Pigmentar/diagnóstico , Proteínas rho de Ligação ao GTP/genéticaRESUMO
OBJECTIVE: To review recent advances in the molecular genetics of retinitis pigmentosa with emphasis on the development of genetic markers that aids diagnosis and prognosis. DATA SOURCES AND EXTRACTION: Literature search of MEDLINE from 1988 to 2005 using the following key words: 'retinitis pigmentosa', 'rhodopsin', 'RP1', 'RPGR', and 'genetic counseling'. References of two genes--RHO and RP1--causing retinitis pigmentosa in the Chinese population were reviewed. STUDY SELECTION: Literature and data related to genetic markers for retinitis pigmentosa. DATA SYNTHESIS: The genetics of retinitis pigmentosa is complex. It can be sporadic or familial, with heterogeneous transmission modes. Retinitis pigmentosa is associated with nearly 40 chromosomal loci, where 32 candidate genes have been identified. A large number of mutations are known to cause retinitis pigmentosa. But no single mutation alone accounts for more than 10% of unrelated retinitis pigmentosa patients. Genetic tests for retinitis pigmentosa require screening for a consort of mutations in a large number of genes. High throughput screening technology such as denaturing high performance liquid chromatography and automated DNA sequencing should make such tests feasible. CONCLUSIONS: Rapid developments in the understanding of the genetics of retinitis pigmentosa have helped to establish genetic tests of clinical value. The complex mode of inheritance nonetheless makes genetic counselling difficult, even in the presence of positive genetic screening results.
Assuntos
Retinose Pigmentar/diagnóstico , Retinose Pigmentar/genética , Mapeamento Cromossômico , Proteínas do Olho/genética , Marcadores Genéticos , Testes Genéticos , Humanos , Proteínas Associadas aos Microtúbulos , Mutação , Prognóstico , Retinose Pigmentar/prevenção & controle , Proteínas rho de Ligação ao GTP/genéticaRESUMO
When retinal ganglion cells undergo apoptosis after optic nerve (ON) injury, microglial cells proliferate and promptly clear the degenerated debris in the ipsilateral retina. However, microglial changes in the contralateral retina have not been fully elucidated. This study characterized the long-term bilateral retinal microglial responses after unilateral ON transection. We analyzed the time course of proliferation and morphology changes of microglial cells, between 3 days and 12 weeks post ON transection, of undisturbed and reactive microglia in bilateral retinas of adult Fischer rats with unilateral ON transection. Microglia in retinas without ON transection were distributed homogeneously and possessed a highly ramified morphology, as judged by immunohistochemistry for ionized calcium-binding adapter molecule 1 (Iba1). After ON transection, microglia density in the ipsilateral retina increased gradually from 3 days to 2 weeks, and decreased from 3 weeks to 12 weeks, along with dramatic inverted alteration of process branch points of microglia in the ganglion cell layer (GCL). Transformation of ramified microglia into ameboid-like macrophages with few branching processes was observed in the ipsilateral retina from 1 week to 3 weeks. Though an increase in microglial density was weak in the contralateral retina and could only be statistically detected in the central retina, the morphological alteration over time was obvious and similar to that of the ipsilateral retina. In the inner plexiform layer (IPL), cell density and morphological changes of microglia in both the ipsilateral and contralateral retina were not prominent. These findings indicates that, though proliferation of microglial cells is weak in the contralateral retina after unilateral ON transection, conspicuous alterations in microglial morphology occur bilaterally. These suggest that using the contralateral retina as a control in studies of retinal degeneration should be considered with caution.
Assuntos
Lateralidade Funcional/fisiologia , Microglia/fisiologia , Traumatismos do Nervo Óptico/fisiopatologia , Retina/fisiopatologia , Animais , Proteínas de Ligação ao Cálcio/metabolismo , Contagem de Células , Proliferação de Células/fisiologia , Modelos Animais de Doenças , Feminino , Imuno-Histoquímica , Macrófagos/patologia , Macrófagos/fisiologia , Proteínas dos Microfilamentos/metabolismo , Microglia/patologia , Traumatismos do Nervo Óptico/patologia , Ratos Endogâmicos F344 , Retina/patologiaRESUMO
The Cambridge Healthtech Institute's Microarrays and Microchips conference was held in Tokyo, Japan, 4-5 June 2001.
Assuntos
Biotecnologia/tendências , Análise de Sequência com Séries de Oligonucleotídeos , Regulação da Expressão Gênica/genética , Regulação da Expressão Gênica/fisiologia , Marcadores Genéticos , Humanos , Farmacogenética , Proteínas/farmacologiaRESUMO
Heterozygous truncating mutations in the RP1 gene cause approximately 7% of autosomal dominant retinitis pigmentosa (RP) cases. To examine the role of RP1 mutations in RP, we screened 101 unrelated Chinese RP patients (unselected for mode of inheritance) and 190 elderly normal control subjects for sequence changes in the coding exons for the 2156 amino acid RP1 protein. One patient had a mutation, thus RP1 mutations cause about 0.0% to 5.4% (95% confidence interval) of all RP among Chinese. The mutation was R677X, the most common found in Americans. Five other known sequence changes were found. In addition, nine novel sequence alterations were identified: 746G>A (R249H), 1437G>T (M479I), 2116G>C (G706R), 3024G>A (Q1008Q), 3188G>A (Q1063R), 5797C>T (R1933X), 6423A>G (I2141M), and the variants 6542C>T and 6676T>A, both in the 3' untranslated region. One control subject and three members of a non-RP family were heterozygous for R1933X, which is therefore likely to be a non-disease-causing variant. The most C-terminal truncation previously reported was due to Tyr1053 (1-bp del) and occurred in RP patients. Thus the presence of a normal level of at least part of RP1 between amino acids 1052 and 1933 appears necessary to prevent RP. Hum Mutat 17:436, 2001.
Assuntos
Povo Asiático/genética , Códon sem Sentido/genética , Proteínas do Olho/química , Proteínas do Olho/genética , Variação Genética/genética , Retinose Pigmentar/genética , Retinose Pigmentar/fisiopatologia , Regiões 3' não Traduzidas/genética , Adolescente , Adulto , Idoso , Criança , Análise Mutacional de DNA , Éxons/genética , Proteínas do Olho/metabolismo , Feminino , Frequência do Gene , Testes Genéticos , Genótipo , Hong Kong , Humanos , Masculino , Proteínas Associadas aos Microtúbulos , Pessoa de Meia-Idade , Linhagem , Fenótipo , Sítios de Splice de RNA/genética , Deleção de Sequência/genéticaRESUMO
Previous mutational analysis for BRCA gene mutations in sporadic ovarian cancer occurring in Chinese patients in Hong Kong identified six germline BRCA1 mutations and one germline BRCA2 mutation, six of which were novel (Khoo et al., 2000). Knowledge of BRCA gene mutations in the Chinese population is relatively scant. In this study, we focussed on whether any of these mutations could be recurrent in our Chinese population, making use of archival paraffin embedded tissue. A consecutive series of 214 ovarian cancer cases, half of Southern Chinese origin from Hong Kong whilst the other half of Northern Chinese origin from Beijing were used for the study. We identified one further novel mutation, 1081delG, in BRCA1. This was found to occur in two unrelated individuals with shared haplotype as revealed by allelotype analysis, thus demonstrating founder effect. Two other recurrent mutations were also identified, the 2371-2372delTG mutation in BRCA1 and the 3337C>T mutation in BRCA2 recurring in two and three unrelated individuals respectively, giving an overall prevalence 4.7% of recurrent BRCA mutations in ovarian cancer in the Southern Chinese population. Most importantly, all our recurrent mutation carriers were identified from Southern Chinese patients from Hong Kong whilst such mutations were absent in samples from the Northern Chinese. Our findings indicate possible heterogeneity in the BRCA genotype between Northern and Southern Chinese. The identification of a founder mutation and two recurrent mutations moreover, has important implications towards screening strategies for breast and ovarian cancer among Chinese of southern ancestral origin who are now dispersed throughout the world.
Assuntos
Povo Asiático/genética , Carcinoma/genética , Efeito Fundador , Genes BRCA1 , Genes BRCA2 , Mutação em Linhagem Germinativa/genética , Neoplasias Ovarianas/genética , Adulto , Idoso , Carcinoma/patologia , China/etnologia , Feminino , Genética Populacional , Humanos , Pessoa de Meia-Idade , Neoplasias Ovarianas/patologia , Espanha/epidemiologiaRESUMO
OBJECTIVE: To study the Ala53Thr and Ala30Pro mutations of the alpha-synuclein gene in a large number of Chinese patients with Parkinson disease (PD) as well as controls. METHODS: We recruited 183 Chinese patients with sporadic PD, 17 with younger-onset PD (onset age <50 years), and 7 with PD and a positive family history as well as 227 unaffected Chinese control subjects from the outpatient departments of 2 major hospitals in Hong Kong. All subjects were assessed for the the diagnosis of PD by a consultant neurologist or geriatrician. Subjects were interviewed with a standard questionnaire that also questioned for family history. Venous blood samples were obtained from the subjects and genomic DNA was extracted and studied for the presence of Ala53Thr mutation in exon 4 and Ala30Pro mutation in exon 3 of the alpha-synuclein gene using a polymerase chain reaction restriction fragment length polymorphism method. RESULTS: None of the Chinese PD patients or controls had either the Ala53Thr (exon 4) or Ala30Pro (exon 3) mutation of the alpha-synuclein gene. CONCLUSION: We failed to discover Ala53Thr or Ala30Pro mutations in a large number of Chinese patients with PD and control subjects, adding to the emerging consensus that variations in the alpha-synuclein gene are associated with PD in few families worldwide.
Assuntos
Mutação , Proteínas do Tecido Nervoso/genética , Doença de Parkinson/epidemiologia , Doença de Parkinson/genética , Alelos , Substituição de Aminoácidos/genética , China/etnologia , Análise Mutacional de DNA , Feminino , Testes Genéticos , Genética Populacional , Hong Kong/epidemiologia , Humanos , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase , Polimorfismo de Fragmento de Restrição , Sinucleínas , alfa-SinucleínaRESUMO
We studied the apolipoprotein E (apoE) allele frequencies in 65 Chinese patients with late-onset Alzheimer's disease (AD) and 82 age- and sex-matched controls. The apoE epsilon 4 allele frequency was significantly higher in the AD group than in the control group (0.169 versus, p < 0.01). There were five homozygotes for epsilon 4 in the AD group but none among the controls. The odds ratio for AD was 1.6 for epsilon 4 heterozygotes. The age at onset was lower in the presence of the epsilon 4 allele and higher with the epsilon 2 allele, although neither of these differences reached statistical significance. The association between apoE alleles and AD previously reported in Caucasian populations was also present in this reports of lower prevalence of AD compared with the prevalence of multi-infarct dementia.