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1.
BMC Public Health ; 22(1): 822, 2022 04 25.
Artículo en Inglés | MEDLINE | ID: mdl-35468743

RESUMEN

BACKGROUND: In Australia in 2017, 89% of 15-year-old females and 86% of 15-year-old males had received at least one dose of the HPV vaccine. However, considerable variation in HPV vaccination initiation (dose one) across schools remains. It is important to understand the school-level characteristics most strongly associated with low initiation and their contribution to the overall between-school variation. METHODS: A population-based ecological analysis was conducted using school-level data for 2016 on all adolescent students eligible for HPV vaccination in three Australian jurisdictions. We conducted logistic regression to determine school-level factors associated with lower HPV vaccination initiation (< 75% dose 1 uptake) and estimated the population attributable risk (PAR) and the proportion of schools with the factor (school-level prevalence). RESULTS: The factors most strongly associated with lower initiation, and their prevalence were; small schools (OR = 9.3, 95%CI = 6.1-14.1; 33% of schools), special education schools (OR = 5.6,95%CI = 3.7-8.5; 8% of schools), higher Indigenous enrolments (OR = 2.7,95% CI:1.9-3.7; 31% of schools), lower attendance rates (OR = 2.6,95%CI = 1.7-3.7; 35% of schools), remote location (OR = 2.6,95%CI = 1.6-4.3; 6% of schools,) and lower socioeconomic area (OR = 1.8,95% CI = 1.3-2.5; 33% of schools). The highest PARs were small schools (PAR = 79%, 95%CI:76-82), higher Indigenous enrolments (PAR = 38%, 95%CI: 31-44) and lower attendance rate (PAR = 37%, 95%CI: 29-46). CONCLUSION: This analysis suggests that initiatives to support schools that are smaller, with a higher proportion of Indigenous adolescents and lower attendance rates may contribute most to reducing the variation of HPV vaccination uptake observed at a school-level in these jurisdictions. Estimating population-level coverage at the school-level is useful to guide policy and prioritise resourcing to support school-based vaccination programs.


Asunto(s)
Infecciones por Papillomavirus , Vacunas contra Papillomavirus , Adolescente , Australia/epidemiología , Femenino , Humanos , Masculino , Infecciones por Papillomavirus/prevención & control , Instituciones Académicas , Vacunación
2.
BMC Bioinformatics ; 20(1): 254, 2019 May 16.
Artículo en Inglés | MEDLINE | ID: mdl-31096927

RESUMEN

BACKGROUND: Next-generation sequencing is revolutionising diagnosis and treatment of rare diseases, however its application to understanding common disease aetiology is limited. Rare disease applications binarily attribute genetic change(s) at a single locus to a specific phenotype. In common diseases, where multiple genetic variants within and across genes contribute to disease, binary modelling cannot capture the burden of pathogenicity harboured by an individual across a given gene/pathway. We present GenePy, a novel gene-level scoring system for integration and analysis of next-generation sequencing data on a per-individual basis that transforms NGS data interpretation from variant-level to gene-level. This simple and flexible scoring system is intuitive and amenable to integration for machine learning, network and topological approaches, facilitating the investigation of complex phenotypes. RESULTS: Whole-exome sequencing data from 508 individuals were used to generate GenePy scores. For each variant a score is calculated incorporating: i) population allele frequency estimates; ii) individual zygosity, determined through standard variant calling pipelines and; iii) any user defined deleteriousness metric to inform on functional impact. GenePy then combines scores generated for all variants observed into a single gene score for each individual. We generated a matrix of ~ 14,000 GenePy scores for all individuals for each of sixteen popular deleteriousness metrics. All per-gene scores are corrected for gene length. The majority of genes generate GenePy scores < 0.01 although individuals harbouring multiple rare highly deleterious mutations can accumulate extremely high GenePy scores. In the absence of a comparator metric, we examine GenePy performance in discriminating genes known to be associated with three common, complex diseases. A Mann-Whitney U test conducted on GenePy scores for this positive control gene in cases versus controls demonstrates markedly more significant results (p = 1.37 × 10- 4) compared to the most commonly applied association tool that combines common and rare variation (p = 0.003). CONCLUSIONS: Per-gene per-individual GenePy scores are intuitive when assessing genetic variation in individual patients or comparing scores between groups. GenePy outperforms the currently accepted best practice tools for combining common and rare variation. GenePy scores are suitable for downstream data integration with transcriptomic and proteomic data that also report at the gene level.


Asunto(s)
Secuenciación de Nucleótidos de Alto Rendimiento/métodos , Programas Informáticos , Virulencia/genética , Alelos , Estudios de Cohortes , Bases de Datos Genéticas , Exoma , Frecuencia de los Genes/genética , Humanos , Fenotipo , Polimorfismo de Nucleótido Simple/genética , Secuenciación del Exoma , Cigoto/metabolismo
3.
Clin Genet ; 89(2): E1-3, 2016 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-26235277

RESUMEN

Next-generation sequencing has accelerated the identification of disease genes in many rare genetic disorders including early-onset epileptic encephalopathies (EOEEs). While many of these disorders are caused by neuronal channelopathies, the role of synaptic and related neuronal proteins are increasingly being described. Here, we report a 6-year-old girl with unexplained EOEE characterized by multifocal seizures and profound global developmental delay. Recessive inheritance was considered due to parental consanguinity and Irish Traveller descent. Exome sequencing was performed. Variant prioritization identified a homozygous nonsense variant in the N-ethylmaleimide-sensitive factor attachment protein, beta (NAPB) gene resulting in a premature stop codon and 46% loss of the protein. NAPB plays a role in soluble N-ethylmaleimide-sensitive fusion attachment protein receptor (SNARE)-complex dissociation and recycling (synaptic vesicle docking). Knockout mouse models of the murine ortholog Napb have been previously reported. These mice develop recurrent post-natal epileptic seizures in the absence of structural brain changes. The identification of a disease-causing variant in NAPB further recognizes the importance of the SNARE complex in the development of epilepsy and suggests that this gene should be considered in patients with unexplained EOEE.


Asunto(s)
Epilepsia/epidemiología , Epilepsia/genética , Proteínas SNARE/metabolismo , Edad de Inicio , Niño , Exoma/genética , Femenino , Humanos
4.
Heredity (Edinb) ; 117(5): 375-382, 2016 11.
Artículo en Inglés | MEDLINE | ID: mdl-27381324

RESUMEN

The analysis of linkage disequilibrium (LD) underpins the development of effective genotyping technologies, trait mapping and understanding of biological mechanisms such as those driving recombination and the impact of selection. We apply the Malécot-Morton model of LD to create additive LD maps that describe the high-resolution LD landscape of commercial chickens. We investigated LD in chickens (Gallus gallus) at the highest resolution to date for broiler, white egg and brown egg layer commercial lines. There is minimal concordance between breeds of fine-scale LD patterns (correlation coefficient <0.21), and even between discrete broiler lines. Regions of LD breakdown, which may align with recombination hot spots, are enriched near CpG islands and transcription start sites (P<2.2 × 10-16), consistent with recent evidence described in finches, but concordance in hot spot locations between commercial breeds is only marginally greater than random. As in other birds, functional elements in the chicken genome are associated with recombination but, unlike evidence from other bird species, the LD landscape is not stable in the populations studied. The development of optimal genotyping panels for genome-led selection programmes will depend on careful analysis of the LD structure of each line of interest. Further study is required to fully elucidate the mechanisms underlying highly divergent LD patterns found in commercial chickens.


Asunto(s)
Pollos/genética , Desequilibrio de Ligamiento , Recombinación Genética , Animales , Cruzamiento , Mapeo Cromosómico , Genética de Población , Técnicas de Genotipaje , Polimorfismo de Nucleótido Simple , Análisis de Secuencia de ADN
5.
Clin Genet ; 88(5): 441-9, 2015 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-25441681

RESUMEN

Individuals from three families ascertained in Bogota, Colombia, showing syndromic phenotypes, including cleft lip and/or palate, were exome-sequenced. In each case, sequencing revealed the underlying causal variation confirming or establishing diagnoses. The findings include very rare and novel variants providing insights into genotype and phenotype relationships. These include the molecular diagnosis of an individual with Nager syndrome and a family exhibiting an atypical incontinentia pigmenti phenotype with a missense mutation in IKBKG. IKBKG mutations are typically associated with preterm male death, but this variant is associated with survival for 8-15 days. The third family exhibits unusual phenotypic features and the proband received a provisional diagnosis of Pierre Robin sequence (PRS). Affected individuals share a novel deleterious mutation in IRF6. Mutations in IRF6 cause Van der Woude and popliteal pterygium syndrome and contribute to nonsyndromic cleft lip phenotypes but have not previously been associated with a PRS phenotype. Exome sequencing followed by in silico screening to identify candidate causal variant(s), and functional assay in some cases offers a powerful route to establishing molecular diagnoses. This approach is invaluable for conditions showing phenotypic and/or genetic heterogeneity including cleft lip and/or palate phenotypes where many underlying causal genes have not been identified.


Asunto(s)
Labio Leporino/genética , Fisura del Paladar/genética , Análisis Mutacional de ADN , Mutación , Fenotipo , Anomalías Múltiples/genética , Adulto , Niño , Labio Leporino/diagnóstico , Labio Leporino/metabolismo , Fisura del Paladar/diagnóstico , Fisura del Paladar/metabolismo , Simulación por Computador , Exoma , Femenino , Humanos , Quinasa I-kappa B/genética , Lactante , Factores Reguladores del Interferón/metabolismo , Masculino , Linaje , Síndrome
6.
Mol Psychiatry ; 19(8): 872-9, 2014 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-24126926

RESUMEN

Schizophrenia (SZ) and autism spectrum disorders (ASDs) are complex neurodevelopmental disorders that may share an underlying pathology suggested by shared genetic risk variants. We sequenced the exonic regions of 215 genes in 147 ASD cases, 273 SZ cases and 287 controls, to identify rare risk mutations. Genes were primarily selected for their function in the synapse and were categorized as: (1) Neurexin and Neuroligin Interacting Proteins, (2) Post-synaptic Glutamate Receptor Complexes, (3) Neural Cell Adhesion Molecules, (4) DISC1 and Interactors and (5) Functional and Positional Candidates. Thirty-one novel loss-of-function (LoF) variants that are predicted to severely disrupt protein-coding sequence were detected among 2 861 rare variants. We found an excess of LoF variants in the combined cases compared with controls (P=0.02). This effect was stronger when analysis was limited to singleton LoF variants (P=0.0007) and the excess was present in both SZ (P=0.002) and ASD (P=0.001). As an individual gene category, Neurexin and Neuroligin Interacting Proteins carried an excess of LoF variants in cases compared with controls (P=0.05). A de novo nonsense variant in GRIN2B was identified in an ASD case adding to the growing evidence that this is an important risk gene for the disorder. These data support synapse formation and maintenance as key molecular mechanisms for SZ and ASD.


Asunto(s)
Trastornos Generalizados del Desarrollo Infantil/genética , Predisposición Genética a la Enfermedad/genética , Mutación/genética , Proteínas del Tejido Nervioso/genética , Esquizofrenia/genética , Estudios de Casos y Controles , Femenino , Humanos , Masculino , Persona de Mediana Edad , Población Blanca/genética
7.
Acta Paediatr ; 104(8): 831-7, 2015 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-25847524

RESUMEN

AIM: There has been at least a twofold increase in the incidence of paediatric inflammatory bowel disease (PIBD) over the last 20 years; we report the presenting features from 2010 to 2013 and compare with previous data. METHODS: All patients diagnosed with PIBD at University Hospitals Southampton from 2010 to 2013 were identified from an in-house database. Data were obtained from paper and electronic notes. Height, weight and BMI SDS are presented as median values (95% CI). RESULTS: One hundred and seventy-two patients were included (median age at diagnosis 13.5, 115 male); Crohn's disease (CD) - 107, UC - 50, inflammatory bowel disease unclassified (IBDU) - 15. The most common presenting features of CD were abdominal pain (86%), diarrhoea (78.5%) and weight loss (56.1%); 42.1% of patients had all three. In UC blood in stool (92%), diarrhoea (92%) and abdominal pain (88%) were the most common; all three in 76% of patients. CD presented with ileocolonic disease in 52.5%. UC presented with pancolitis in 64%. There was growth delay in CD: height -0.37 (-0.60 to -0.14); weight -1.09 (-1.35 to -0.83). Growth was maintained in UC: height 0.53 (0.19 to 0.87); weight 0.14 (-0.20 to 0.48). CONCLUSION: Paediatric inflammatory bowel disease phenotype remains as extensive despite increasing incidence. Although the classical phenotype is common, a reasonable proportion present with atypical features, normal growth and normal blood markers.


Asunto(s)
Enfermedades Inflamatorias del Intestino , Adolescente , Inglaterra , Femenino , Humanos , Enfermedades Inflamatorias del Intestino/diagnóstico , Enfermedades Inflamatorias del Intestino/genética , Enfermedades Inflamatorias del Intestino/terapia , Masculino , Factores de Tiempo
8.
Diabetologia ; 56(4): 758-62, 2013 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-23385738

RESUMEN

AIMS/HYPOTHESIS: 6q24 transient neonatal diabetes mellitus (TNDM) is a rare form of diabetes presenting in the neonatal period that remits during infancy but, in a proportion of cases, recurs in later life. We aim to describe the clinical presentation of 6q24 TNDM in the largest worldwide cohort of patients with defined molecular aetiology, in particular seeking differences in presentation or clinical history between aetiological groups. METHODS: One-hundred and sixty-three patients with positively diagnosed 6q24 TNDM were ascertained from Europe, the Americas, Asia and Australia. Clinical data from referrals were recorded and stratified by the molecular aetiology of patients. RESULTS: 6q24 TNDM patients presented at a modal age of one day, with growth retardation and hyperglycaemia, irrespective of molecular aetiology. There was a positive correlation between age of presentation and gestational age, and a negative correlation between adjusted birthweight SD and age of remission. Congenital anomalies were significantly more frequent in patients with paternal uniparental disomy of chromosome 6 or hypomethylation of multiple imprinted loci defects than in those with 6q24 duplication or isolated hypomethylation defects. Patients with hypomethylation had an excess representation of assisted conception at 15%. CONCLUSIONS/INTERPRETATION: This, the largest case series of 6q24 TNDM published, refines and extends the clinical phenotype of the disorder and confirms its clinical divergence from other monogenic TNDM in addition to identifying previously unreported clinical differences between 6q24 subgroups.


Asunto(s)
Cromosomas Humanos Par 6 , Diabetes Mellitus/genética , Anomalías Múltiples/genética , Edad de Inicio , Estudios de Cohortes , Metilación de ADN , Diabetes Mellitus/diagnóstico , Femenino , Estudios de Asociación Genética , Impresión Genómica , Genotipo , Edad Gestacional , Humanos , Recién Nacido , Enfermedades del Recién Nacido/genética , Masculino , Fenotipo , Inducción de Remisión , Disomía Uniparental/genética
9.
Anim Genet ; 44(4): 408-12, 2013 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-23278111

RESUMEN

Equine osteochondrosis is a developmental joint disease that is a significant source of morbidity affecting multiple breeds of horse. The genetic variants underlying osteochondrosis susceptibility have not been established. Here, we describe the results of a genome-wide association study of osteochondrosis using 90 cases and 111 controls from a population of Dutch Warmblood horses. We report putative associations between osteochondrosis and loci on chromosome 3 (BIEC2-808543; P = 5.03 × 10(-7) ) and chromosome 10 (BIEC2-121323; P = 2.62 × 10(-7) ).


Asunto(s)
Cromosomas de los Mamíferos/genética , Estudio de Asociación del Genoma Completo/veterinaria , Enfermedades de los Caballos/genética , Artropatías/veterinaria , Osteocondrosis/veterinaria , Animales , Cruzamiento , Mapeo Cromosómico/veterinaria , Femenino , Sitios Genéticos/genética , Predisposición Genética a la Enfermedad , Estudio de Asociación del Genoma Completo/métodos , Genotipo , Haplotipos , Enfermedades de los Caballos/diagnóstico por imagen , Caballos , Artropatías/diagnóstico por imagen , Artropatías/genética , Masculino , Osteocondrosis/diagnóstico por imagen , Osteocondrosis/genética , Fenotipo , Polimorfismo de Nucleótido Simple , Radiografía
10.
Sci Rep ; 11(1): 19029, 2021 09 24.
Artículo en Inglés | MEDLINE | ID: mdl-34561486

RESUMEN

The SARS-CoV-2 pandemic has highlighted the weaknesses of relying on single-use mask and respirator personal protective equipment (PPE) and the global supply chain that supports this market. There have been no major innovations in filter technology for PPE in the past two decades. Non-woven textiles used for filtering PPE are single-use products in the healthcare environment; use and protection is focused on preventing infection from airborne or aerosolized pathogens such as Influenza A virus or SARS-CoV-2. Recently, C-H bond activation under mild and controllable conditions was reported for crosslinking commodity aliphatic polymers such as polyethylene and polypropylene. Significantly, these are the same types of polymers used in PPE filtration systems. In this report, we take advantage of this C-H insertion method to covalently attach a photosensitizing zinc-porphyrin to the surface of a melt-blow non-woven textile filter material. With the photosensitizer covalently attached to the surface of the textile, illumination with visible light was expected to produce oxidizing 1O2/ROS at the surface of the material that would result in pathogen inactivation. The filter was tested for its ability to inactivate Influenza A virus, an enveloped RNA virus similar to SARS-CoV-2, over a period of four hours with illumination of high intensity visible light. The photosensitizer-functionalized polypropylene filter inactivated our model virus by 99.99% in comparison to a control.


Asunto(s)
COVID-19/virología , Diazometano/química , Luz , Fármacos Fotosensibilizantes/química , Fármacos Fotosensibilizantes/farmacología , Polipropilenos/química , SARS-CoV-2/efectos de los fármacos , SARS-CoV-2/efectos de la radiación
11.
Vaccine ; 39(41): 6117-6126, 2021 10 01.
Artículo en Inglés | MEDLINE | ID: mdl-34493408

RESUMEN

BACKGROUND: Schools are the primary setting for the delivery of adolescent HPV vaccination in Australia. Although this strategy has achieved generally high vaccination coverage, gaps persist for reasons that are mostly unknown. This study sought to identify school-level correlates of low vaccination course initiation and completion in New South Wales, Tasmania, and Western Australia to inform initiatives to increase uptake. METHODS: Initiation was defined as the number of first doses given in a school in 2016 divided by vaccine-eligible student enrolments. Completion was the number of third doses given in a school in 2015-2016 divided by the number of first doses. Low initiation and completion were defined as coverage ≤ 25thpercentile of all reporting schools. We investigated correlations between covariates using Spearman's rank correlation coefficients. Due to multicollinearity, we used univariable logistic regression to investigate associations between school characteristics and low coverage. RESULTS: Median initiation was 84.7% (IQR: 75.0%-90.4%) across 1,286 schools and median completion was 93.8% (IQR: 86.0%-97.3%) across 1,295 schools. There were strong correlations between a number of school characteristics, particularly higher Indigenous student enrolments and lower attendance, increasing remoteness, higher postcode socioeconomic disadvantage, and smaller school size. Characteristics most strongly associated with low initiation in univariate analyses were small school size, location in Tasmania, and schools catering for special educational needs. Low completion was most strongly associated with schools in Tasmania and Western Australia, remote location, small size, high proportion of Indigenous student enrolments, and low attendance rates. CONCLUSION: This study provides indicative evidence that characteristics of schools and school populations are associated with the likelihood of low initiation and completion of the HPV vaccination course. The findings will guide further research and help target initiatives to improve vaccination uptake in schools with profiles associated with lower coverage.


Asunto(s)
Infecciones por Papillomavirus , Vacunas contra Papillomavirus , Adolescente , Australia , Humanos , Programas de Inmunización , Infecciones por Papillomavirus/prevención & control , Instituciones Académicas , Vacunación
12.
Anim Genet ; 41 Suppl 2: 2-7, 2010 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-21070269

RESUMEN

The recent completion of the horse genome and commercial availability of an equine SNP genotyping array has facilitated the mapping of disease genes. We report putative localization of the gene responsible for dwarfism, a trait in Friesian horses that is thought to have a recessive mode of inheritance, to a 2-MB region of chromosome 14 using just 10 affected animals and 10 controls. We successfully genotyped 34,429 SNPs that were tested for association with dwarfism using chi-square tests. The most significant SNP in our study, BIEC2-239376 (P(2df)=4.54 × 10(-5), P(rec)=7.74 × 10(-6)), is located close to a gene implicated in human dwarfism. Fine-mapping and resequencing analyses did not aid in further localization of the causative variant, and replication of our findings in independent sample sets will be necessary to confirm these results.


Asunto(s)
Enanismo/veterinaria , Estudio de Asociación del Genoma Completo , Enfermedades de los Caballos/genética , Polimorfismo de Nucleótido Simple , Animales , Enanismo/genética , Caballos
13.
NPJ Digit Med ; 3: 30, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32195365

RESUMEN

Autoimmune diseases are chronic, multifactorial conditions. Through machine learning (ML), a branch of the wider field of artificial intelligence, it is possible to extract patterns within patient data, and exploit these patterns to predict patient outcomes for improved clinical management. Here, we surveyed the use of ML methods to address clinical problems in autoimmune disease. A systematic review was conducted using MEDLINE, embase and computers and applied sciences complete databases. Relevant papers included "machine learning" or "artificial intelligence" and the autoimmune diseases search term(s) in their title, abstract or key words. Exclusion criteria: studies not written in English, no real human patient data included, publication prior to 2001, studies that were not peer reviewed, non-autoimmune disease comorbidity research and review papers. 169 (of 702) studies met the criteria for inclusion. Support vector machines and random forests were the most popular ML methods used. ML models using data on multiple sclerosis, rheumatoid arthritis and inflammatory bowel disease were most common. A small proportion of studies (7.7% or 13/169) combined different data types in the modelling process. Cross-validation, combined with a separate testing set for more robust model evaluation occurred in 8.3% of papers (14/169). The field may benefit from adopting a best practice of validation, cross-validation and independent testing of ML models. Many models achieved good predictive results in simple scenarios (e.g. classification of cases and controls). Progression to more complex predictive models may be achievable in future through integration of multiple data types.

14.
Acta Neurochir Suppl ; 105: 73-7, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-19066086

RESUMEN

In this paper, we review current knowledge on blood-brain barrier (BBB) dysfunction following intracerebral hemorrhage (ICH). BBB disruption is a hallmark of ICH-induced brain injury. Such disruption contributes to edema formation, the influx of leukocytes, and the entry of potentially neuroactive agents into the perihematomal brain, all of which may contribute to brain injury. A range of factors have been implicated in inducing BBB disruption, including inflammatory mediators (e.g., cytokines and chemokines), thrombin, hemoglobin breakdown products, oxidative stress, complement, and matrix metalloproteinases. While there is interaction between some of these mediators, it is probable that prevention of ICH-induced BBB disruption will involve blocking multiple pathways or blocking a common end pathway (e.g., by stabilizing tight junction structure). While the effects of ICH on BBB passive permeability have been extensively examined, effects on other 'barrier' properties (metabolic and transport functions) have been less well-studied. However, recent data suggests that ICH can affect transport and that this may help protect the BBB and the brain. Indeed, it is possible in small bleeds that BBB disruption may be beneficial, and it is only in the presence of larger bleeds that disruption has detrimental effects.


Asunto(s)
Barrera Hematoencefálica/fisiopatología , Hemorragia Cerebral/patología , Animales , Barrera Hematoencefálica/efectos de los fármacos , Hemorragia Cerebral/tratamiento farmacológico , Humanos
15.
Hum Mutat ; 28(12): 1216-24, 2007 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-17674408

RESUMEN

In its expanded form, the fragile X triplet repeat at Xq27.3 gives rise to the most common form of inherited mental retardation, fragile X syndrome. This high population frequency persists despite strong selective pressure against mutation-bearing chromosomes. Males carrying the full mutation rarely reproduce and females heterozygous for the premutation allele are at risk of premature ovarian failure. Our diagnostic facility and previous research have provided a large databank of X chromosomes that have been tested for the FRAXA allele. Using this resource, we have conducted a detailed genetic association study of the FRAXA region to determine any cis-acting factors that predispose to expansion of the CGG triplet repeat. We have genotyped SNP variants across a 650-kb tract centered on FRAXA in a sample of 877 expanded and normal X chromosomes. These chromosomes were selected to be representative of the haplotypic diversity encountered in our population. We found expansion status to be strongly associated with a approximately 50-kb region proximal to the fragile site. Subsequent detailed analyses of this region revealed no specific genetic determinants for the whole population. However, stratification of chromosomes by risk subgroups enabled us to identify a common SNP variant which cosegregates with the subset of D group haplotypes at highest risk of expansion (chi(1)(2)=17.84, p=0.00002). We have verified that this SNP acts as a marker of repeat expansion in three independent samples.


Asunto(s)
Proteína de la Discapacidad Intelectual del Síndrome del Cromosoma X Frágil/genética , Síndrome del Cromosoma X Frágil/genética , Haplotipos , Expansión de Repetición de Trinucleótido , Cromosomas Humanos X/genética , Femenino , Predisposición Genética a la Enfermedad , Genotipo , Humanos , Escala de Lod , Masculino , Polimorfismo de Nucleótido Simple/genética
16.
Sci Rep ; 7(1): 2427, 2017 05 25.
Artículo en Inglés | MEDLINE | ID: mdl-28546534

RESUMEN

Paediatric inflammatory bowel disease (PIBD), comprising Crohn's disease (CD), ulcerative colitis (UC) and inflammatory bowel disease unclassified (IBDU) is a complex and multifactorial condition with increasing incidence. An accurate diagnosis of PIBD is necessary for a prompt and effective treatment. This study utilises machine learning (ML) to classify disease using endoscopic and histological data for 287 children diagnosed with PIBD. Data were used to develop, train, test and validate a ML model to classify disease subtype. Unsupervised models revealed overlap of CD/UC with broad clustering but no clear subtype delineation, whereas hierarchical clustering identified four novel subgroups characterised by differing colonic involvement. Three supervised ML models were developed utilising endoscopic data only, histological only and combined endoscopic/histological data yielding classification accuracy of 71.0%, 76.9% and 82.7% respectively. The optimal combined model was tested on a statistically independent cohort of 48 PIBD patients from the same clinic, accurately classifying 83.3% of patients. This study employs mathematical modelling of endoscopic and histological data to aid diagnostic accuracy. While unsupervised modelling categorises patients into four subgroups, supervised approaches confirm the need of both endoscopic and histological evidence for an accurate diagnosis. Overall, this paper provides a blueprint for ML use with clinical data.


Asunto(s)
Enfermedades Inflamatorias del Intestino/diagnóstico , Aprendizaje Automático , Adolescente , Factores de Edad , Niño , Preescolar , Análisis por Conglomerados , Femenino , Humanos , Lactante , Recién Nacido , Masculino , Modelos Teóricos , Curva ROC , Reproducibilidad de los Resultados , Aprendizaje Automático Supervisado , Aprendizaje Automático no Supervisado
17.
Acta Neurochir Suppl ; 96: 276-8, 2006.
Artículo en Inglés | MEDLINE | ID: mdl-16671470

RESUMEN

Although the effects of cerebral ischemia on the blood-brain barrier have been extensively studied, the effects on the blood-cerebrospinal fluid barrier (BCSFB) at the choroid plexuses have received much less attention. This paper reviews evidence on the effects of cerebral ischemia on the choroid plexus, particularly focusing on the degree of blood flow reduction required to damage the lateral ventricle choroid plexuses during transient forebrain ischemia, and whether disruption of the BCSFB might affect nearby tissues. Studies have shown that 2 common models of forebrain ischemia (4-vessel and 2-vessel with hypotension) cause damage to the lateral ventricle choroid plexus via necrosis and apoptosis. We have found that bilateral common carotid artery occlusion with hypotension causes an 87% reduction in lateral ventricle choroid plexus blood flow during ischemia and an approximate tripling of the permeability of the BCSFB to inulin after 6 hours of reperfusion. Interestingly, evidence suggests that this disruption of the BCSFB rather than disruption to the blood-brain barrier is the major cause of enhanced inulin entry into the hippocampus. The hippocampus undergoes selective delayed neuronal loss in that model of forebrain ischemia and the BCSFB disruption may participate in or modulate that delayed injury.


Asunto(s)
Barrera Hematoencefálica/metabolismo , Barrera Hematoencefálica/patología , Isquemia Encefálica/sangre , Isquemia Encefálica/líquido cefalorraquídeo , Prosencéfalo/irrigación sanguínea , Prosencéfalo/patología , Animales
18.
Acta Neurochir Suppl ; 96: 295-8, 2006.
Artículo en Inglés | MEDLINE | ID: mdl-16671474

RESUMEN

This study examines the effect of 2,4-dinitrophenol (DNP), a mitochondrial uncoupling agent, during focal brain ischemia induced by middle cerebral artery (MCA) occlusion. Blood-brain barrier (BBB) disruption was assessed after 2 hours of occlusion with 2 hours of reperfusion or 4 hours of permanent occlusion by measurement of the influx rate constant (K(i)) for 3H-inulin in the MCA territory ipsi- and contralateral to the occlusion. Three experimental groups were examined: vehicle and 1 and 5 mg/kg DNP treated animals (given 30 minutes prior to occlusion). Four hours of permanent MCA occlusion only induced a modest increase in the K(i) for inulin in vehicle-treated animals (0.09 +/- 0.01 vs. 0.07 +/- 0.01 microL/g/min in contralateral tissue). Although 5 mg/kg DNP significantly increased this disruption (p < 0.01), this effect was relatively minor (0.14 +/- 0.02 microL/g/min). In contrast, DNP treatment in transient ischemia markedly increased barrier disruption. The ipsilateral K(i) for 3H-inulin were 0.15 +/- 0.04, 0.37 +/- 0.06, and 0.79 +/- 0.17 microL/g/min in vehicle, 1 mg/kg DNP and 5 mg/kg DNP groups, respectively. DNP did not induce barrier disruption in the contralateral hemisphere. Thus, while there is evidence that DNP can be neuroprotective, it has adverse effects on the BBB during ischemia, particularly with reperfusion. Considering the importance of naturally- or therapeutically-induced reperfusion in limiting brain damage, this may limit the utility of DNP and mitochondrial uncouplers as therapeutic agents.


Asunto(s)
2,4-Dinitrofenol/administración & dosificación , Barrera Hematoencefálica/efectos de los fármacos , Barrera Hematoencefálica/fisiopatología , Isquemia Encefálica/fisiopatología , Encéfalo/efectos de los fármacos , Encéfalo/fisiopatología , Animales , Isquemia Encefálica/tratamiento farmacológico , Relación Dosis-Respuesta a Droga , Masculino , Ratas , Ratas Sprague-Dawley , Desacopladores/administración & dosificación
19.
Leukemia ; 30(6): 1301-10, 2016 06.
Artículo en Inglés | MEDLINE | ID: mdl-26847028

RESUMEN

The biological features of IGHV-M chronic lymphocytic leukemia responsible for disease progression are still poorly understood. We undertook a longitudinal study close to diagnosis, pre-treatment and post relapse in 13 patients presenting with cMBL or Stage A disease and good-risk biomarkers (IGHV-M genes, no del(17p) or del(11q) and low CD38 expression) who nevertheless developed progressive disease, of whom 10 have required therapy. Using cytogenetics, fluorescence in situ hybridisation, genome-wide DNA methylation and copy number analysis together with whole exome, targeted deep- and Sanger sequencing at diagnosis, we identified mutations in established chronic lymphocytic leukemia driver genes in nine patients (69%), non-coding mutations (PAX5 enhancer region) in three patients and genomic complexity in two patients. Branching evolutionary trajectories predominated (n=9/13), revealing intra-tumoural epi- and genetic heterogeneity and sub-clonal competition before therapy. Of the patients subsequently requiring treatment, two had sub-clonal TP53 mutations that would not be detected by standard methodologies, three qualified for the very-low-risk category defined by integrated mutational and cytogenetic analysis and yet had established or putative driver mutations and one patient developed progressive, therapy-refractory disease associated with the emergence of an IGHV-U clone. These data suggest that extended genomic and immunogenetic screening may have clinical utility in patients with apparent good-risk disease.


Asunto(s)
Exoma/genética , Dosificación de Gen , Cadenas Pesadas de Inmunoglobulina/genética , Leucemia Linfocítica Crónica de Células B/genética , Mutación , Adolescente , Adulto , Anciano , Células Clonales , Análisis Citogenético , Progresión de la Enfermedad , Heterogeneidad Genética , Secuenciación de Nucleótidos de Alto Rendimiento , Humanos , Estudios Longitudinales , Persona de Mediana Edad , Riesgo , Adulto Joven
20.
J Med Genet ; 37(6): 415-21, 2000 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-10851251

RESUMEN

We report the results of a five year survey of FRAXA and FRAXE mutations among boys aged 5 to 18 with special educational needs (SEN) related to learning disability. We tested their mothers using the X chromosome not transmitted to the son as a control chromosome, and the X chromosome inherited by the son to provide information on stability of transmission. We tested 3738 boys and 2968 mothers and found 20 FRAXA and one FRAXE full mutations among the boys and none among the mothers. This gives an estimated prevalence of full mutations in males of 1 in 5530 for FRAXA and 1 in 23 423 for FRAXE. We found an excess of intermediate and premutation alleles for both FRAXA and FRAXE. For FRAXA this was significant at the 0.001 level but the excess for FRAXE was significant only at the 0.03 level. We conclude that the excess of intermediate and premutation sized alleles for FRAXA may well be a contributing factor to the boys' mental impairment, while that for FRAXE may be a chance finding. We studied approximately 3000 transmissions from mother to son and found five instabilities of FRAXA in the common or intermediate range and three instabilities of FRAXE in the intermediate range. Thus instabilities in trinucleotide repeat size for FRAXA and FRAXE are rare, especially among alleles in the common size range.


Asunto(s)
Síndrome del Cromosoma X Frágil/genética , Pruebas Genéticas , Mutación/genética , Adolescente , Adulto , Alelos , Niño , Preescolar , Análisis Mutacional de ADN , Educación Especial , Inglaterra/epidemiología , Femenino , Síndrome del Cromosoma X Frágil/diagnóstico , Síndrome del Cromosoma X Frágil/epidemiología , Síndrome del Cromosoma X Frágil/fisiopatología , Frecuencia de los Genes/genética , Encuestas Epidemiológicas , Humanos , Cariotipificación , Síndrome de Klinefelter/diagnóstico , Síndrome de Klinefelter/epidemiología , Síndrome de Klinefelter/genética , Síndrome de Klinefelter/fisiopatología , Discapacidades para el Aprendizaje/epidemiología , Discapacidades para el Aprendizaje/genética , Discapacidades para el Aprendizaje/fisiopatología , Masculino , Madres , Prevalencia , Factores de Tiempo , Expansión de Repetición de Trinucleótido/genética , Cromosoma X/genética
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