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1.
Int J Mol Sci ; 24(17)2023 Sep 04.
Artículo en Inglés | MEDLINE | ID: mdl-37686457

RESUMEN

The human eye plays a critical role in vision perception, but various retinal degenerative diseases such as retinitis pigmentosa (RP), glaucoma, and age-related macular degeneration (AMD) can lead to vision loss or blindness. Although progress has been made in understanding retinal development and in clinical research, current treatments remain inadequate for curing or reversing these degenerative conditions. Animal models have limited relevance to humans, and obtaining human eye tissue samples is challenging due to ethical and legal considerations. Consequently, researchers have turned to stem cell-based approaches, specifically induced pluripotent stem cells (iPSCs), to generate distinct retinal cell populations and develop cell replacement therapies. iPSCs offer a novel platform for studying the key stages of human retinogenesis and disease-specific mechanisms. Stem cell technology has facilitated the production of diverse retinal cell types, including retinal ganglion cells (RGCs) and photoreceptors, and the development of retinal organoids has emerged as a valuable in vitro tool for investigating retinal neuron differentiation and modeling retinal diseases. This review focuses on the protocols, culture conditions, and techniques employed in differentiating retinal neurons from iPSCs. Furthermore, it emphasizes the significance of molecular and functional validation of the differentiated cells.


Asunto(s)
Células Madre Pluripotentes Inducidas , Degeneración Retiniana , Neuronas Retinianas , Animales , Humanos , Retina , Diferenciación Celular , Degeneración Retiniana/terapia , Ceguera
2.
Int J Mol Sci ; 24(21)2023 Oct 30.
Artículo en Inglés | MEDLINE | ID: mdl-37958721

RESUMEN

Coronavirus disease 2019 (COVID-19) has been linked to various neurological complications. This meta-analysis assessed the relationship between glial fibrillary acidic protein (GFAP) and neurofilament light chain (NfL) levels in the blood and neurological injury in COVID-19 patients. A comprehensive search of various databases was conducted until 18 August 2023, to find studies reporting GFAP and NfL blood levels in COVID-19 patients with neurological complications. GFAP and NfL levels were estimated between COVID-19 patients and healthy controls, and meta-analyses were performed using RevMan 5.4 software for analysis. In the 21 collected studies, it was found that COVID-19 patients had significantly higher levels of pooled GFAP (SMD = 0.52; 95% CI: 0.31, 0.73; p ≤ 0.001) and NfL (SMD = 0.60; 95% CI: 0.37, 0.82; p ≤ 0.001) when compared to the healthy controls. The pooled GFAP (SMD = 0.86; 95% CI: 0.26, 1.45; p ≤ 0.01) and NfL (SMD = 0.87; 95% CI: 0.48, 1.26; p ≤ 0.001) were significantly higher in non-survivors. These findings indicate a significant association between COVID-19 severity and elevated levels of GFAP and NfL, suggesting that GFAP and NfL could serve as potential diagnostic and prognostic markers for the early detection and monitoring of COVID-19-related neurological injuries.


Asunto(s)
COVID-19 , Humanos , Pronóstico , COVID-19/complicaciones , Biomarcadores , Proteína Ácida Fibrilar de la Glía , Proteínas de Neurofilamentos , Filamentos Intermedios/metabolismo
3.
Emerg Infect Dis ; 27(1): 196-204, 2021 01.
Artículo en Inglés | MEDLINE | ID: mdl-33350913

RESUMEN

Initial cases of coronavirus disease in Hong Kong were imported from mainland China. A dramatic increase in case numbers was seen in February 2020. Most case-patients had no recent travel history, suggesting the presence of transmission chains in the local community. We collected demographic, clinical, and epidemiologic data from 50 patients, who accounted for 53.8% of total reported case-patients as of February 28, 2020. We performed whole-genome sequencing to determine phylogenetic relationship and transmission dynamics of severe acute respiratory syndrome coronavirus 2 infections. By using phylogenetic analysis, we attributed the community outbreak to 2 lineages; 1 harbored a common mutation, Orf3a-G251V, and accounted for 88.0% of the cases in our study. The estimated time to the most recent common ancestor of local coronavirus disease outbreak was December 24, 2019, with an evolutionary rate of 3.04 × 10-3 substitutions/site/year. The reproduction number was 1.84, indicating ongoing community spread.


Asunto(s)
COVID-19/epidemiología , COVID-19/virología , Brotes de Enfermedades , Adulto , Anciano , Anciano de 80 o más Años , COVID-19/transmisión , Análisis por Conglomerados , Punto Alto de Contagio de Enfermedades , Evolución Molecular , Femenino , Hong Kong/epidemiología , Humanos , Masculino , Persona de Mediana Edad , Mutación , Filogenia , Filogeografía , SARS-CoV-2/genética , SARS-CoV-2/aislamiento & purificación , Proteínas Viroporinas/genética , Secuenciación Completa del Genoma , Adulto Joven
4.
Biochim Biophys Acta Gen Subj ; 1861(2): 335-353, 2017 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-27888147

RESUMEN

BACKGROUND: Genome-wide association studies (GWAS) is a major method for studying the genetics of complex diseases. Finding all sequence variants to explain fully the aetiology of a disease is difficult because of their small effect sizes. To better explain disease mechanisms, pathway analysis is used to consolidate the effects of multiple variants, and hence increase the power of the study. While pathway analysis has previously been performed within GWAS only, it can now be extended to examining rare variants, other "-omics" and interaction data. SCOPE OF REVIEW: 1. Factors to consider in the choice of software for GWAS pathway analysis. 2. Examples of how pathway analysis is used to analyse rare variants, other "-omics" and interaction data. MAJOR CONCLUSIONS: To choose appropriate software tools, factors for consideration include covariate compatibility, null hypothesis, one- or two-step analysis required, curation method of gene sets, size of pathways, and size of flanking regions to define gene boundaries. For rare variants, analysis performance depends on consistency between assumed and actual effect distribution of variants. Integration of other "-omics" data and interaction can better explain gene functions. GENERAL SIGNIFICANCE: Pathway analysis methods will be more readily used for integration of multiple sources of data, and enable more accurate prediction of phenotypes.


Asunto(s)
Polimorfismo de Nucleótido Simple/genética , Transducción de Señal/genética , Estudio de Asociación del Genoma Completo/métodos , Humanos , Programas Informáticos
5.
Ultraschall Med ; 38(2): 190-197, 2017 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-25830344

RESUMEN

Purpose To comprehensively evaluate and compare the degree of carotid atherosclerosis in patients treated with radiotherapy (RT) for nasopharyngeal carcinoma (NPC) and in patients with type 2 diabetes mellitus (DM), and using healthy subjects as controls. Materials and Methods The present study recruited 69 post-RT NPC patients without conventional cardiovascular risk factors, 70 type 2 diabetic patients without previous RT, and 76 healthy controls without conventional cardiovascular risk factors and previous RT. For each participant, 5 carotid atherosclerotic parameters, namely carotid intima-media thickness (CIMT), carotid arterial stiffness (CAS), presence of carotid plaque, carotid plaque score, and presence of ≥ 50 % carotid stenosis, were assessed using ultrasonography. The differences in these carotid atherosclerotic parameters between study groups were compared using ANCOVA or logistic regression after the adjustment for age and gender. Multiple comparisons were corrected using the Benjamini-Hochberg false discovery rate. Results Post-RT NPC patients and type 2 diabetics had a significantly higher CIMT, CAS and carotid plaque burden compared to the healthy subjects (corrected P-value, Pcor < 0.05). In addition, carotid atherosclerosis in post-RT NPC patients tended to be more severe with significantly higher CAS and carotid plaque burden than that in type 2 diabetics (Pcor < 0.05). Conclusion Neck RT for NPC is an independent risk factor of carotid atherosclerosis, and radiation induces more severe carotid atherosclerosis in post-RT NPC patients. Thus, assessment of carotid atherosclerosis using ultrasonography may be necessary for these patients and should be indicated in the routine follow-up of NPC.


Asunto(s)
Enfermedades de las Arterias Carótidas/diagnóstico por imagen , Diabetes Mellitus Tipo 2/diagnóstico por imagen , Neoplasias Nasofaríngeas/radioterapia , Traumatismos por Radiación/diagnóstico por imagen , Adulto , Anciano , Anciano de 80 o más Años , Arteria Carótida Común/diagnóstico por imagen , Arteria Carótida Común/efectos de la radiación , Grosor Intima-Media Carotídeo , Estenosis Carotídea/diagnóstico por imagen , Femenino , Humanos , Interpretación de Imagen Asistida por Computador , Masculino , Persona de Mediana Edad , Valores de Referencia , Factores de Riesgo , Rigidez Vascular/fisiología , Adulto Joven
6.
Hum Genet ; 134(2): 131-46, 2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-25367360

RESUMEN

To identify genetic variants associated with refractive astigmatism in the general population, meta-analyses of genome-wide association studies were performed for: White Europeans aged at least 25 years (20 cohorts, N = 31,968); Asian subjects aged at least 25 years (7 cohorts, N = 9,295); White Europeans aged <25 years (4 cohorts, N = 5,640); and all independent individuals from the above three samples combined with a sample of Chinese subjects aged <25 years (N = 45,931). Participants were classified as cases with refractive astigmatism if the average cylinder power in their two eyes was at least 1.00 diopter and as controls otherwise. Genome-wide association analysis was carried out for each cohort separately using logistic regression. Meta-analysis was conducted using a fixed effects model. In the older European group the most strongly associated marker was downstream of the neurexin-1 (NRXN1) gene (rs1401327, P = 3.92E-8). No other region reached genome-wide significance, and association signals were lower for the younger European group and Asian group. In the meta-analysis of all cohorts, no marker reached genome-wide significance: The most strongly associated regions were, NRXN1 (rs1401327, P = 2.93E-07), TOX (rs7823467, P = 3.47E-07) and LINC00340 (rs12212674, P = 1.49E-06). For 34 markers identified in prior GWAS for spherical equivalent refractive error, the beta coefficients for genotype versus spherical equivalent, and genotype versus refractive astigmatism, were highly correlated (r = -0.59, P = 2.10E-04). This work revealed no consistent or strong genetic signals for refractive astigmatism; however, the TOX gene region previously identified in GWAS for spherical equivalent refractive error was the second most strongly associated region. Analysis of additional markers provided evidence supporting widespread genetic co-susceptibility for spherical and astigmatic refractive errors.


Asunto(s)
Astigmatismo/genética , Moléculas de Adhesión Celular Neuronal/genética , Estudio de Asociación del Genoma Completo , Proteínas del Grupo de Alta Movilidad/genética , Proteínas del Tejido Nervioso/genética , Adulto , Factores de Edad , Pueblo Asiatico , Astigmatismo/patología , Proteínas de Unión al Calcio , Estudios de Cohortes , Femenino , Marcadores Genéticos , Humanos , Masculino , Persona de Mediana Edad , Moléculas de Adhesión de Célula Nerviosa , Población Blanca
7.
Nat Genet ; 38(1): 38-46, 2006 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-16369534

RESUMEN

Severe acute respiratory syndrome (SARS) is caused by infection of a previously undescribed coronavirus (CoV). L-SIGN, encoded by CLEC4M (also known as CD209L), is a SARS-CoV binding receptor that has polymorphism in its extracellular neck region encoded by the tandem repeat domain in exon 4. Our genetic risk association study shows that individuals homozygous for CLEC4M tandem repeats are less susceptible to SARS infection. L-SIGN is expressed in both non-SARS and SARS-CoV-infected lung. Compared with cells heterozygous for L-SIGN, cells homozygous for L-SIGN show higher binding capacity for SARS-CoV, higher proteasome-dependent viral degradation and a lower capacity for trans infection. Thus, homozygosity for L-SIGN plays a protective role during SARS infection.


Asunto(s)
Moléculas de Adhesión Celular/genética , Lectinas Tipo C/genética , Receptores de Superficie Celular/genética , Síndrome Respiratorio Agudo Grave/genética , Coronavirus Relacionado al Síndrome Respiratorio Agudo Severo/patogenicidad , Animales , Células CHO/virología , Moléculas de Adhesión Celular/metabolismo , Chlorocebus aethiops , Estudios de Cohortes , Cricetinae , Cricetulus , Predisposición Genética a la Enfermedad , Homocigoto , Hong Kong/epidemiología , Humanos , Intestino Delgado/fisiología , Lectinas Tipo C/metabolismo , Pulmón/fisiología , Pulmón/virología , Datos de Secuencia Molecular , Complejo de la Endopetidasa Proteasomal/metabolismo , Receptores de Superficie Celular/metabolismo , Coronavirus Relacionado al Síndrome Respiratorio Agudo Severo/metabolismo , Síndrome Respiratorio Agudo Grave/epidemiología , Secuencias Repetidas en Tándem , Células Vero/virología
8.
J Physiol ; 592(12): 2535-48, 2014 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-24639483

RESUMEN

Elevations of cardiomyocyte apoptosis and fibrotic deposition are major characteristics of the ageing heart. Resveratrol, a polyphenol in grapes and red wine, is known to improve insulin resistance and increase mitochondrial biogenesis through the SIRT1-PGC-1α signalling axis. Recent studies attempted to relate SIRT1 activation by resveratrol to the regulation of apoptosis in various disease models of cardiac muscle. In the present study, we tested the hypothesis that long-term (8-month) treatment of resveratrol would activate SIRT1 and improve the cardiac function of senescent mice through suppression of Foxo1-associated pro-apoptotic signalling. Our echocardiographic measurements indicated that the cardiac systolic function measured as fractional shortening and ejection fraction was significantly reduced in aged mice when compared with the young mice. These reductions, however, were not observed in resveratrol-treated hearts. Ageing significantly reduced the deacetylase activity, but not the protein abundance of SIRT1 in the heart. This reduction was accompanied by increased acetylation of the Foxo1 transcription factor and transactivation of its target, pro-apoptotic Bim. Subsequent analyses indicated that pro-apoptotic signalling measured as p53, Bax and apoptotic DNA fragmentation was up-regulated in the heart of aged mice. In contrast, resveratrol restored SIRT1 activity and suppressed elevations of Foxo1 acetylation, Bim and pro-apoptotic signalling in the aged heart. In parallel, resveratrol also attenuated the ageing-induced elevations of fibrotic collagen deposition and markers of oxidative damage including 4HNE and nitrotyrosine. In conclusion, these novel data demonstrate that resveratrol mitigates pro-apoptotic signalling in senescent heart through a deacetylation mechanism of SIRT1 that represses the Foxo1-Bim-associated pro-apoptotic signalling axis.


Asunto(s)
Envejecimiento/fisiología , Factores de Transcripción Forkhead/metabolismo , Corazón/efectos de los fármacos , Sirtuina 1/metabolismo , Estilbenos/farmacología , Acetilación/efectos de los fármacos , Animales , Apoptosis/efectos de los fármacos , Colágeno/metabolismo , Complejo IV de Transporte de Electrones/metabolismo , Proteína Forkhead Box O1 , Corazón/fisiología , Frecuencia Cardíaca/efectos de los fármacos , Ratones , Resveratrol , Transducción de Señal/efectos de los fármacos , Función Ventricular Izquierda/efectos de los fármacos
9.
Am J Physiol Endocrinol Metab ; 306(3): E311-23, 2014 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-24326424

RESUMEN

Doxorubicin is an effective chemotherapeutic agent used to treat malignancies, but it causes cardiomyopathy. Preliminary evidence suggests that desacyl ghrelin might have protective effects on doxorubicin cardiotoxicity. This study examined the cellular effects of desacyl ghrelin on myocardial fibrosis and apoptosis in a doxorubicin cardiomyopathy experimental model. Adult C57BL/6 mice received an intraperitoneal injection of doxorubicin to induce cardiomyopathy, followed by 4-day treatment of saline (control) or desacyl ghrelin with or without [d-Lys3]-GHRP-6 (a growth hormone secretagogue receptor or GHSR1a antagonist). Ventricular structural and functional parameters were evaluated by transthoracic echocardiography. Molecular and cellular measurements were performed in ventricular muscle to examine myocardial fibrosis and apoptosis. Cardiac dysfunction was induced by doxorubicin, as indicated by significant decreases in ventricular fractional shortening and ejection fraction. This doxorubicin-induced cardiac dysfunction was prevented by the treatment of desacyl ghrelin no matter with or without the presence of [d-Lys3]-GHRP-6. Doxorubicin induced fibrosis (accumulated collagen deposition and increased CTGF), activated apoptosis (increased TUNEL index, apoptotic DNA fragmentation, and caspase-3 activity and decreased Bcl-2/Bax ratio), and suppressed phosphorylation status of prosurvival signals (ERK1/2 and Akt) in ventricular muscles. All these molecular and cellular alterations induced by doxorubicin were not found in the animals treated with desacyl ghrelin. Notably, the changes in the major markers of apoptosis, fibrosis, and Akt phosphorylation were found to be similar in the animals following the treatment of desacyl ghrelin with and without GHSR antagonist [d-Lys3]-GHRP-6. These findings demonstrate clearly that desacyl ghrelin protects the cardiomyocytes against the doxorubicin-induced cardiomyopathy by preventing the activation of cardiac fibrosis and apoptosis, and the effects are probably mediated through GHSR-independent mechanism.


Asunto(s)
Apoptosis/efectos de los fármacos , Cardiomiopatías/prevención & control , Cardiotónicos/farmacología , Doxorrubicina/efectos adversos , Ghrelina/uso terapéutico , Miocardio/patología , Animales , Cardiomiopatías/inducido químicamente , Citoprotección/efectos de los fármacos , Evaluación Preclínica de Medicamentos , Fibrosis , Corazón/efectos de los fármacos , Masculino , Ratones , Ratones Endogámicos C57BL , Receptores de Ghrelina/fisiología , Transducción de Señal/efectos de los fármacos
10.
BMC Genet ; 15: 147, 2014 Dec 20.
Artículo en Inglés | MEDLINE | ID: mdl-25526816

RESUMEN

BACKGROUND: Myeloproliferative neoplasms (MPNs) are a group of haematological malignancies that can be characterised by a somatic mutation (JAK2V617F). This mutation causes the bone marrow to produce excessive blood cells and is found in polycythaemia vera (~95%), essential thrombocythaemia and primary myelofibrosis (both ~50%). It is considered as a major genetic factor contributing to the development of these MPNs. No genetic association study of MPN in the Hong Kong population has so far been reported. Here, we investigated the relationship between germline JAK2 polymorphisms and MPNs in Hong Kong Chinese to find causal variants that contribute to MPN development. We analysed 19 tag single nucleotide polymorphisms (SNPs) within the JAK2 locus in 172 MPN patients and 470 healthy controls. Three of these 19 SNPs defined the reported JAK2 46/1 haplotype: rs10974944, rs12343867 and rs12340895. Allele and haplotype frequencies were compared between patients and controls by logistic regression adjusted for sex and age. Permutation test was used to correct for multiple comparisons. With significant findings from the 19 SNPs, we then examined 76 additional SNPs across the 148.7-kb region of JAK2 via imputation with the SNP data from the 1000 Genomes Project. RESULTS: In single-marker analysis, 15 SNPs showed association with JAK2V617F-positive MPNs (n = 128), and 8 of these were novel MPN-associated SNPs not previously reported. Exhaustive variable-sized sliding-window haplotype analysis identified 184 haplotypes showing significant differences (P < 0.05) in frequencies between patients and controls even after multiple-testing correction. However, single-marker alleles exhibited the strongest association with V617F-positive MPNs. In local Hong Kong Chinese, rs12342421 showed the strongest association signal: asymptotic P = 3.76 × 10-15, empirical P = 2.00 × 10-5 for 50,000 permutations, OR = 3.55 for the minor allele C, and 95% CI, 2.59-4.87. Conditional logistic regression also signified an independent effect of rs12342421 in significant haplotype windows, and this independent effect remained unchanged even with the imputation of additional 76 SNPs. No significant association was found between V617F-negative MPNs and JAK2 SNPs. CONCLUSION: With a large sample size, we reported the association between JAK2V617F-positive MPNs and 15 tag JAK2 SNPs and the association of rs12342421 being independent of the JAK2 46/1 haplotype in Hong Kong Chinese population.


Asunto(s)
Pueblo Asiatico/genética , Janus Quinasa 2/genética , Trastornos Mieloproliferativos/genética , Polimorfismo de Nucleótido Simple , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Estudios de Casos y Controles , Análisis Mutacional de ADN , Femenino , Estudios de Asociación Genética , Genotipo , Haplotipos , Hong Kong , Humanos , Desequilibrio de Ligamiento , Masculino , Persona de Mediana Edad , Adulto Joven
11.
Trop Med Int Health ; 18(9): 1097-1102, 2013 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-23718710

RESUMEN

OBJECTIVES: To assess the extent of dengue virus exposure in the population. METHODS: In this seroepidemiological study, 685 blood samples were collected (from April 2007 to July 2009) from two subject groups: (i) 344 samples from anonymous blood donors of the Hong Kong Red Cross and (ii) 341 samples from healthy volunteers recruited from a university, a community centre and a hospital. Demographic information and travel history were collected for the second subject group. All blood samples were subjected to the PanBio Dengue IgG Indirect ELISA. RESULTS: Anti-dengue virus IgG was detected in 1.6% of the blood samples. Individuals who visited countries in Southeast Asia in the past year were significantly associated with seropositivity (P = 0.03, OR 5.38, CI 1.13-25.54). CONCLUSIONS: The overall dengue seroprevalence was 1.6%, and visit to Southeast Asia was the only independent predictor for seropositivity. Although the current situation is not alarming, frequent travel, presence of mosquito vector and emergence of local cases suggest that the risk of dengue virus infection within the local community cannot be overlooked, and continuous vigilance is warranted.


Asunto(s)
Aedes/virología , Donantes de Sangre , Dengue/epidemiología , Insectos Vectores , Viaje , Adolescente , Adulto , Anciano , Animales , Anticuerpos Antivirales/sangre , Asia Sudoriental , Dengue/inmunología , Dengue/virología , Virus del Dengue/inmunología , Virus del Dengue/aislamiento & purificación , Ensayo de Inmunoadsorción Enzimática , Femenino , Hong Kong/epidemiología , Humanos , Inmunoglobulina G/sangre , Masculino , Persona de Mediana Edad , Estudios Seroepidemiológicos , Adulto Joven
12.
Ophthalmic Physiol Opt ; 33(3): 346-53, 2013 May.
Artículo en Inglés | MEDLINE | ID: mdl-23406521

RESUMEN

PURPOSE: Myopia is a complex eye disorder. The X-linked form of complete congenital stationary night blindness (CSNB1A) is usually associated with moderate to high myopia, and is caused by mutations in the NYX gene. We explored if NYX mutations could be associated with high myopia, but not CSNB1A. METHODS: The coding regions of the NYX gene were sequenced for 204 Chinese males with high myopia (-8.00 dioptres or worse for both eyes). The frequencies of any sequence variations identified were determined in 200 Chinese males without myopia. Electro-oculography, electroretinography and standard cone function tests were performed on a male high myope carrying a mutation. RESULTS: A missense mutation (c.529_530GC>AT or p.Ala177Met) was identified in one male subject with high myopia, but not in 200 male emmetropes. Neither was this variant found in any of the 529 male and 567 female subjects of various ethnic backgrounds whose genome sequences are documented in the 1000 Genomes Project database. The mutation was predicted to affect the protein function. From ocular electrophysiological tests, the proband was found to have normal rod function, but mildly abnormal cone function and inner retina function. He did not seem to suffer from CSNB1A. CONCLUSIONS: One novel missense NYX mutation was identified in an adult male presented with high myopia, but without the major electrophysiological features normally associated with CSNB1A. NYX gene mutations may be considered as one of the rare genetic risk factors for high myopia without key features of CSNB1A.


Asunto(s)
Predisposición Genética a la Enfermedad/genética , Mutación Missense/genética , Miopía/genética , Proteoglicanos/genética , Pueblo Asiatico/genética , China , Emetropía/genética , Exones , Humanos , Masculino , Persona de Mediana Edad , Ceguera Nocturna/genética , Análisis de Secuencia de ADN
13.
Cells ; 12(13)2023 06 30.
Artículo en Inglés | MEDLINE | ID: mdl-37443789

RESUMEN

Artificial intelligence (AI) is a rapidly evolving field of computer science that involves the development of computational programs that can mimic human intelligence. In particular, machine learning and deep learning models have enabled the identification and grouping of patterns within data, leading to the development of AI systems that have been applied in various areas of hematology, including digital pathology, alpha thalassemia patient screening, cytogenetics, immunophenotyping, and sequencing. These AI-assisted methods have shown promise in improving diagnostic accuracy and efficiency, identifying novel biomarkers, and predicting treatment outcomes. However, limitations such as limited databases, lack of validation and standardization, systematic errors, and bias prevent AI from completely replacing manual diagnosis in hematology. In addition, the processing of large amounts of patient data and personal information by AI poses potential data privacy issues, necessitating the development of regulations to evaluate AI systems and address ethical concerns in clinical AI systems. Nonetheless, with continued research and development, AI has the potential to revolutionize the field of hematology and improve patient outcomes. To fully realize this potential, however, the challenges facing AI in hematology must be addressed and overcome.


Asunto(s)
Inteligencia Artificial , Enfermedades Hematológicas , Humanos , Enfermedades Hematológicas/diagnóstico , Enfermedades Hematológicas/genética , Citogenética , Perfil Genético , Pruebas Genéticas
14.
Small ; 8(2): 214-9, 2012 Jan 23.
Artículo en Inglés | MEDLINE | ID: mdl-22095584

RESUMEN

A facile silica coating significantly enhances the thermal stability and polymerase chain reaction (PCR) compatibility of oligonucleotide-gold nanoparticle conjugates, thus enabling colorimetric detection of PCR results in a closed-tube format. This method is specific, sensitive, and generally applicable. Its simplicity, visual readout, and carryover contamination-free features hold promise for point-of-care or on-site DNA testing.


Asunto(s)
Colorimetría/métodos , ADN/análisis , ADN/genética , Nanopartículas del Metal , Oligodesoxirribonucleótidos/química , Oligodesoxirribonucleótidos/genética , Reacción en Cadena de la Polimerasa/métodos , Secuencia de Bases , Cartilla de ADN/química , Cartilla de ADN/genética , Oro , Dióxido de Silicio
15.
BMC Med Genet ; 13: 64, 2012 Aug 02.
Artículo en Inglés | MEDLINE | ID: mdl-22857148

RESUMEN

BACKGROUND: The UMODL1 gene was found to be associated with high myopia in Japanese. This study aimed to investigate this gene for association with high myopia in Chinese. METHODS: Two groups of unrelated Han Chinese from Hong Kong were recruited using the same criteria: Sample Set 1 comprising 356 controls (spherical equivalent, SE, within ±1 diopter or D) and 356 cases (SE ≤ -8D), and Sample Set 2 comprising 394 controls and 526 cases. Fifty-nine tag single nucleotide polymorphisms (SNPs) were selected and genotyped for Sample Set 1. Four SNPs were followed up with Sample Set 2. Both single-marker and haplotype analyses were performed with cases defined by different SE thresholds. Secondary phenotypes were also analyzed for association with genotypes. RESULTS: Data filtering left 57 SNPs for analysis. Single-marker analysis did not reveal any significant differences between cases and controls in the initial study. However, haplotype GCT for markers rs220168-rs220170-rs11911271 showed marginal significance (empirical P = 0.076; SE ≤ -12D for cases), but could not be replicated in the follow-up study. In contrast, non-synonymous SNP rs3819142 was associated with high myopia (SE ≤ -10D) in the follow-up study, but could not be confirmed using Sample Set 1. The SNP rs2839471, positive in the original Japanese study, gave negative results in all our analyses. Exploratory analysis of secondary phenotypes indicated that allele C of rs220120 was associated with anterior chamber depth (adjusted P = 0.0460). CONCLUSIONS: Common UMODL1 polymorphisms were unlikely to be important in the genetic susceptibility to high myopia in Han Chinese.


Asunto(s)
Pueblo Asiatico/genética , Proteínas de Unión al Calcio/genética , Proteínas de la Membrana/genética , Miopía/genética , Polimorfismo Genético , Adolescente , Adulto , Pueblo Asiatico/estadística & datos numéricos , Estudios de Casos y Controles , Femenino , Frecuencia de los Genes , Estudios de Asociación Genética/estadística & datos numéricos , Predisposición Genética a la Enfermedad , Haplotipos , Hong Kong/epidemiología , Humanos , Desequilibrio de Ligamiento , Masculino , Miopía/epidemiología , Polimorfismo de Nucleótido Simple , Prevalencia , Índice de Severidad de la Enfermedad , Adulto Joven
16.
BMC Genet ; 13: 1, 2012 Jan 17.
Artículo en Inglés | MEDLINE | ID: mdl-22252406

RESUMEN

BACKGROUND: Despite being a well-established strategy for cost reduction in disease gene mapping, pooled DNA association study is much less popular than the individual DNA approach. This situation is especially true for pooled DNA genomewide association study (GWAS), for which very few computer resources have been developed for its data analysis. This motivates the development of UPDG (Utilities package for data analysis of Pooled DNA GWAS). RESULTS: UPDG represents a generalized framework for data analysis of pooled DNA GWAS with the integration of Unix/Linux shell operations, Perl programs and R scripts. With the input of raw intensity data from GWAS, UPDG performs the following tasks in a stepwise manner: raw data manipulation, correction for allelic preferential amplification, normalization, nested analysis of variance for genetic association testing, and summarization of analysis results. Detailed instructions, procedures and commands are provided in the comprehensive user manual describing the whole process from preliminary preparation of software installation to final outcome acquisition. An example dataset (input files and sample output files) is also included in the package so that users can easily familiarize themselves with the data file formats, working procedures and expected output. Therefore, UPDG is especially useful for users with some computer knowledge, but without a sophisticated programming background. CONCLUSIONS: UPDG provides a free, simple and platform-independent one-stop service to scientists working on pooled DNA GWAS data analysis, but with less advanced programming knowledge. It is our vision and mission to reduce the hindrance for performing data analysis of pooled DNA GWAS through our contribution of UPDG. More importantly, we hope to promote the popularity of pooled DNA GWAS, which is a very useful research strategy.


Asunto(s)
Estudio de Asociación del Genoma Completo , Programas Informáticos , Estadística como Asunto/métodos , Humanos , Interfaz Usuario-Computador
17.
ACS Appl Mater Interfaces ; 14(31): 35299-35308, 2022 Aug 10.
Artículo en Inglés | MEDLINE | ID: mdl-35895859

RESUMEN

Loop-mediated isothermal amplification (LAMP) has received considerable attention for decentralized (point-of-care and on-site) nucleic acid testing in view of its simple temperature control (60-65 °C) and short assay time (15-60 min). There remains a challenge in its wide adoption and acceptance due to the limitations of the existing amplification result reporter probes, e.g., photobleaching of organic fluorophore and reduced sensitivity of the pH-sensitive colorimetric dye. Herein, we demonstrate CdSeS/ZnS quantum dots (semiconductor fluorescent nanocrystals with superior photostability than organic fluorophore) with surface modification of cysteamine (amine-QDs) as a new reporter probe for LAMP that enabled single-copy sensitivity (limit of detection of 83 zM; 20 µL reaction volume). For a negative LAMP sample (absence of target sequence), positively charged amine-QDs remained dispersed due to interparticle electrostatic repulsion. While for a positive LAMP sample (presence of target sequence), amine-QDs became precipitated. The characterization data showed that amine-QDs were embedded in magnesium pyrophosphate crystals (generated during positive LAMP), thus leading to their coprecipitation. This amine-QD-based one-step LAMP assay advances the field of QD-based nucleic acid amplification assays in two aspects: (1) compatibility─one-step amplification and detection (versus separation of amplification and detection steps); and (2) universality─the same amine-QDs for different target sequences (versus different oligonucleotide-modified QDs for different target sequences).


Asunto(s)
Ácidos Nucleicos , Puntos Cuánticos , Aminas , Técnicas de Diagnóstico Molecular , Técnicas de Amplificación de Ácido Nucleico , Sensibilidad y Especificidad
18.
Mol Omics ; 18(5): 449-459, 2022 06 13.
Artículo en Inglés | MEDLINE | ID: mdl-35420081

RESUMEN

Gene expression of the chick retina was examined during the early development of lens-induced myopia (LIM) using whole transcriptome sequencing. Monocular treatment of the right eyes with -10 diopter (D) lenses was performed on newly born chicks for one day (LIM-24) or two days (LIM-48), while the contralateral eyes without lenses served as controls. Myopia development was confirmed by demonstrating significant elongation of the optical axis in lens-treated eyes compared to untreated control eyes. RNA was extracted and RNA-seq was performed using the Illumina HiSeqTM 2000 platform. Data analysis was carried out on a Partek® Flow platform. Using screening criteria of ≥1.30-fold change and a false discovery rate <1%, 11 (five down-regulated and six up-regulated) and 35 differentially expressed genes (six down-regulated and twenty-nine up-regulated) were identified at 24 hours and 48 hours, respectively. Using another cohort for validation, Quantitative PCR confirmed significant changes in the expression of VIP and UTS2B mRNA (P <0.05) after only 24 hours of LIM treatment and numerical changes in the expression for PCGF5 and FOXG1, which were consistent with transcriptome sequencing but did not reach statistical significance. These data suggest that concerted changes of retinal gene expression may be instrumental in the initiation of axial elongation and myopia development.


Asunto(s)
Péptidos y Proteínas de Señalización Intracelular , Miopía , Hormonas Peptídicas , Péptido Intestinal Vasoactivo , Animales , Pollos/genética , Pollos/metabolismo , Regulación hacia Abajo , Factores de Transcripción Forkhead/genética , Factores de Transcripción Forkhead/metabolismo , Péptidos y Proteínas de Señalización Intracelular/genética , Miopía/genética , Miopía/metabolismo , Proteínas del Tejido Nervioso/genética , Hormonas Peptídicas/genética , ARN Mensajero/genética , Retina/metabolismo , Péptido Intestinal Vasoactivo/genética
19.
Am J Hum Genet ; 82(3): 744-7, 2008 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-18304494

RESUMEN

Lumbar-disc degeneration (LDD) is a polygenic disease. Susceptibility genes reported so far are mainly extracellular matrix proteins. D14 allele of asporin (ASPN) is associated with osteoarthritis (OA). Candidate-gene association studies showed that the D14 allele is also significantly associated with LDD in Chinese and Japanese individuals. Meta-analysis showed that individuals harboring a D14 allele had higher risk with a summary odds ratio of 1.70 (p = 0.000013). ASPN expression in vertebral discs increased with age and degeneration. Our results indicate ASPN is a LDD gene in Asians, and common risk factors may be considered for OA and LDD.


Asunto(s)
Pueblo Asiatico/genética , Proteínas de la Matriz Extracelular/genética , Predisposición Genética a la Enfermedad , Disco Intervertebral , Vértebras Lumbares , Osteocondritis/genética , Adolescente , Adulto , Alelos , Ácido Aspártico/química , Ácido Aspártico/genética , Proteínas de la Matriz Extracelular/química , Femenino , Frecuencia de los Genes , Humanos , Masculino , Persona de Mediana Edad , Osteoartritis/genética , Polimorfismo Genético , Secuencias Repetitivas de Aminoácido/genética
20.
Mol Vis ; 17: 810-21, 2011 Mar 26.
Artículo en Inglés | MEDLINE | ID: mdl-21527992

RESUMEN

PURPOSE: We examined the relationship between high myopia and common polymorphisms in four candidate genes: collagen, type XI, alpha 1 (COL11A1); collagen, type XVIII, alpha 1 (COL18A1); fibrillin 1 (FBN1); and procollagen-lysine 1,2-oxoglutarate 5-dioxygenase 1 (PLOD1). These genes were selected because rare pathogenic mutations in these genes cause disease syndromes that have myopia, usually high myopia, as one of the common presenting features. METHODS: This study recruited 600 unrelated Han Chinese subjects including 300 cases with high myopia (spherical equivalent or SE≤-8.00 diopters) and 300 controls (SE within ±1.00 diopter). A total of 66 tag single nucleotide polymorphisms (SNPs) were selected for study from these four candidate genes. The study adopted a DNA pooling strategy with an initial screen of DNA pools to identify putatively positive SNPs and then confirmed the "positive" SNPs by genotyping individual samples forming the original DNA pools. DNA pools were each constructed by mixing equal amounts of DNA from 50 individuals with the same phenotype status. Six case pools were prepared from 300 cases and six control pools from 300 controls. Allele frequencies of DNA pools were estimated by analyzing the primer-extended products with denaturing high performance liquid chromatography and compared between case pools and control pools with nested ANOVA. RESULTS: In the first stage, 60 SNPs from the 4 candidate genes were successfully screened using the DNA pooling approach. Of these, 6 SNPs showed a statistical significant difference in estimated allele frequencies between case pools and controls at p<0.10. In the second stage, these "positive" SNPs were followed up by individual genotyping, but failed to be confirmed via standard single-marker and haplotype analyses. CONCLUSIONS: Common polymorphisms in these four candidate genes (COL11A1, COL18A1, FBN1 and PLOD1) were unlikely to play important roles in the genetic susceptibility to high myopia.


Asunto(s)
Colágeno Tipo XI/genética , Colágeno Tipo XVIII/genética , Proteínas de Microfilamentos/genética , Miopía/genética , Procolágeno-Lisina 2-Oxoglutarato 5-Dioxigenasa/genética , Análisis de Secuencia de ADN/métodos , Adolescente , Adulto , Análisis de Varianza , Pueblo Asiatico/genética , Estudios de Casos y Controles , Colágeno Tipo XI/metabolismo , Colágeno Tipo XVIII/metabolismo , ADN/análisis , Dermatoglifia del ADN , Femenino , Fibrilina-1 , Fibrilinas , Frecuencia de los Genes , Genotipo , Haplotipos , Humanos , Masculino , Proteínas de Microfilamentos/metabolismo , Persona de Mediana Edad , Miopía/patología , Fenotipo , Polimorfismo de Nucleótido Simple , Procolágeno-Lisina 2-Oxoglutarato 5-Dioxigenasa/metabolismo
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