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Characterization of the microbial activity impacts on transport and storage of hydrogen is a crucial aspect of successful Underground Hydrogen Storage (UHS). Microbes can use hydrogen for their metabolism, which can then lead to formation of biofilms. Biofilms can potentially alter the wettability of the system and, consequently, impact the flow dynamics and trapping mechanisms in the reservoir. In this study, we investigate the impact of microbial activity on wettability of the hydrogen/brine/rock system, using the captive-bubble cell experimental approach. Apparent contact angles are measured for bubbles of pure hydrogen in contact with a solid surface inside a cell filled with living brine which contains sulphate reducing microbes. To investigate the impact of surface roughness, two different solid samples are used: a "rough" Bentheimer Sandstone sample and a "smooth" pure Quartz sample. It is found that, in systems where buoyancy and interfacial forces are the main acting forces, the impact of biofilm formation on the apparent contact angle highly depends on the surface roughness. For the "rough" Bentheimer sandstone, the apparent contact angle was unchanged by biofilm formation, while for the smooth pure Quartz sample the apparent contact angle decreased significantly, making the system more water-wet. This decrease in apparent contact angle is in contrast with an earlier study present in the literature where a significant increase in contact angle due to microbial activity was reported. The wettability of the biofilm is mainly determined by the consistency of the Extracellular Polymeric Substances (EPS) which depends on the growth conditions in the system. Therefore, to determine the impact of microbial activity on the wettability during UHS will require accurate replication of the reservoir conditions including surface roughness, chemical composition of the brine, the microbial community, as well as temperature, pressure and pH-value conditions.
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Hidrogênio , Quartzo , Molhabilidade , SaisRESUMO
Geological porous reservoirs provide the volume capacity needed for large scale underground hydrogen storage (UHS). To effectively exploit these reservoirs for UHS, it is crucial to characterize the hydrogen transport properties inside porous rocks. In this work, for the first time in the community, we have performed [Formula: see text]/water multiphase flow experiments at core scale under medical X-ray CT scanner. This has allowed us to directly image the complex transport properties of [Formula: see text] when it is injected or retracted from the porous rock. The important effective functions of capillary pressure and relative permeability are also measured, for both drainage and imbibition. The capillary pressure measurements are combined with MICP data to derive a receding contact angle for the [Formula: see text]/water/sandstone rock system. The rock core sample is a heterogeneous Berea sandstone (17 cm long and 3.8 cm diameter). Our investigation reveals the interplay between gravitational, capillary, and viscous forces. More specifically, it illustrates complex displacement patterns in the rock, including gravity segregation, enhancement of spreading of [Formula: see text] due to capillary barriers, and the formation of fingers/channel during imbibition which lead to significant trapping of hydrogen. These findings shed new light on our fundamental understanding of the transport characteristics of [Formula: see text]/water relevant for UHS.
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OBJECTIVE: It may be difficult for clinicians to estimate the prognosis of pediatric acute transverse myelitis (ATM). The aim of this study was to define prognostic factors for relapsing disease and poor outcome in pediatric ATM. METHODS: This prospective cohort study included 49 children, 18 boys and 31 girls (median age 13.1 years, IQR 6.5-16.2) with a first episode of ATM. Factors associated with relapsing disease and poor outcome (Expanded Disability Status Scale (EDSS) ≥ 4) were assessed during a median follow-up of 37 months (IQR 18-75). RESULTS: In total, 14 patients (29%) experienced ≥ 1 relapse(s) and nine patients (18%) had a poor outcome. Factors at onset associated with relapsing disease included higher age (16.1 vs. 11.6 years, p = 0.002), longer time to maximum severity of symptoms (5.5 vs. 3 days, p = 0.01), lower maximum EDSS score (4.0 vs. 6.5, p = 0.003), short lesion on spinal MRI (64 vs. 21%, p = 0.006), abnormalities on brain MRI (93 vs. 44%, p = 0.002) and presence of oligoclonal bands in cerebrospinal fluid (67 vs. 14%, p = 0.004). The only factor associated with poor outcome was presence of a spinal cord lesion on MRI without cervical involvement (56 vs. 14%, p = 0.02). CONCLUSION: Pediatric ATM patients presenting with clinical, radiological and laboratory features associated with multiple sclerosis (MS) are at risk for relapsing disease. In absence of these known MS risk factors at onset of disease these patients are at low risk for relapses. Only a minority of pediatric ATM patients in this cohort have a poor outcome.
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Esclerose Múltipla/diagnóstico , Mielite Transversa/diagnóstico , Doença Aguda , Adolescente , Criança , Pré-Escolar , Feminino , Seguimentos , Humanos , Masculino , Esclerose Múltipla/metabolismo , Esclerose Múltipla/patologia , Esclerose Múltipla/fisiopatologia , Mielite Transversa/metabolismo , Mielite Transversa/patologia , Mielite Transversa/fisiopatologia , Neuromielite Óptica/diagnóstico , Neuromielite Óptica/metabolismo , Neuromielite Óptica/patologia , Neuromielite Óptica/fisiopatologia , Avaliação de Resultados em Cuidados de Saúde , Prognóstico , RecidivaRESUMO
BACKGROUND: Treatment of palmar and axillary primary focal hyperhidrosis (PFH) in children up to 16 years using thoracoscopic sympathicotomy is supported by scarce evidence. Therefore, this study aimed to summarize the results of our standardized bilateral, one-stage, single-port sympathicotomy (BOSS) in children up to 16 years of age. METHODS: Consecutive children (n = 14) up to 16 years of age undergoing BOSS between October 2011 and June 2015 in our institution were included in this retrospective study. RESULTS: Recurrence of primary hyperhidrosis was noted in seven patients (50.0%), of whom five patients (35.7%) underwent reoperation. Reoperations were associated with placement of additional thoracoscopic ports (n = 1; 12.5%), intraoperative placement of pleural drains (n = 2; 25%), and prolonged air leak (n = 1; 12.5%). Despite the high recurrence and reoperation rates, overall patient satisfaction was high with a median satisfaction score of 7.5 (interquartile range of 1.75; range: 4-9). CONCLUSION: Although the overall patient satisfaction score in our cohort was good, BOSS for the treatment of intolerable palmar and axillary PFH in children up to 16 years of age is associated with a high recurrence and reoperation rate.
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Hiperidrose , Adolescente , Axila , Criança , Feminino , Mãos , Humanos , Hiperidrose/cirurgia , Masculino , Recidiva , Estudos Retrospectivos , Simpatectomia , Resultado do TratamentoRESUMO
This data article provides detailed explanation and data on CO2/water coreflooding experiments performed on nine sandstone rock cores. Refer to the research article "Predicting CO2 Residual Trapping Ability Based on Experimental Petrophysical Properties for Different Sandstone Types" [1] for data interpretation. The reader can expect to find experimental conditions including temperature, pressure, fluid pair types, as well as flow rates. Furthermore, the raw CT images and the processed three-dimensional (3D) voxel-level porosity, permeability, and CO2 saturation maps for each of the nine sandstone samples are also supplied.
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Neurofibromatosis type 1 (NF1) is an autosomal dominant disorder, associated with a variable clinical phenotype including café-au-lait spots, intertriginous freckling, Lisch nodules, neurofibromas, optic pathway gliomas and distinctive bony lesions. NF1 is caused by a mutation in the NF1 gene, which codes for neurofibromin, a large protein involved in the MAPK- and the mTOR-pathway through RAS-RAF signalling. NF1 is a known tumour predisposition syndrome, associated with different tumours of the nervous system including low grade gliomas (LGGs) in the paediatric population. The focus of this review is on grade I pilocytic astrocytomas (PAs), the most commonly observed histologic subtype of low grade gliomas in NF1. Clinically, these PAs have a better prognosis and show different localisation patterns than their sporadic counterparts, which are most commonly associated with a KIAA1549:BRAF fusion. In this review, possible mechanisms of tumourigenesis in LGGs with and without NF1 will be discussed, including the contribution of different signalling pathways and tumour microenvironment. Furthermore we will discuss how increased understanding of tumourigenesis may lead to new potential targets for treatment.
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Glioma/etiologia , Neurofibromatose 1/complicações , Animais , Glioma/diagnóstico , Humanos , Mutação , Gradação de Tumores , Fenótipo , Transdução de Sinais , Microambiente TumoralRESUMO
Mutations in SCN8A are associated with epilepsy and intellectual disability. SCN8A encodes for sodium channel Nav1.6, which is located in the brain. Gain-of-function missense mutations in SCN8A are thought to lead to increased firing of excitatory neurons containing Nav1.6, and therefore to lead to increased seizure susceptibility. We hypothesized that sodium channel blockers could have a beneficial effect in patients with SCN8A-related epilepsy by blocking the overactive Nav1.6 and thereby counteracting the effect of the mutation. Herein, we describe 4 patients with a missense SCN8A mutation and epilepsy who all show a remarkably good response on high doses of phenytoin and loss of seizure control when phenytoin medication was reduced, while side effects were relatively mild. In 2 patients, repeated withdrawal of phenytoin led to the reoccurrence of seizures. Based on the findings in these patients and the underlying molecular mechanism we consider treatment with (high-dose) phenytoin as a possible treatment option in patients with difficult-to-control seizures due to an SCN8A mutation.
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Anticonvulsivantes/uso terapêutico , Epilepsia/genética , Canal de Sódio Disparado por Voltagem NAV1.6/genética , Fenitoína/uso terapêutico , Criança , Pré-Escolar , Epilepsia/tratamento farmacológico , Feminino , Humanos , Masculino , Mutação de Sentido Incorreto/genética , Canal de Sódio Disparado por Voltagem NAV1.6/efeitos dos fármacos , Resultado do TratamentoRESUMO
BACKGROUND: Recently, the International Paediatric Multiple Sclerosis Study Group (IPMSSG) definitions for the diagnosis of immune-mediated acquired demyelinating syndromes (ADS) of the central nervous system, including paediatric multiple sclerosis (MS), have been revised. OBJECTIVE: To evaluate the 2012 revised IPMSSG consensus definitions in a cohort of children with ADS prospectively followed from January 2007. METHODS: Children with ADS who had an MRI scan obtained within 90â days after first disease onset were included. The sensitivity and specificity of the 2007 and 2012 IPMSSG consensus definitions were assessed. The time to MS diagnosis applying the 2007 and 2012 definitions was compared using survival analysis and log-rank test. RESULTS: 82 children with ADS were included. 35 children were diagnosed with paediatric MS, of whom 30 experienced a second clinical event. The final diagnosis corresponded applying either the 2007 or 2012 IPMSSG definitions. The revised 2012 definitions had sufficient sensitivity (80%) and high specificity (100%). MS diagnosis was made 3.4â months earlier (χ(2)=8.24, p=0.004) applying the new definitions. In 14 children, MS diagnosis was made at first MRI. CONCLUSIONS: MS diagnosis can be made reliable and early using the 2012 IPMSSG consensus definitions. This is beneficial for adequate counselling of children and their families and for early treatment possibilities.
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Doenças Autoimunes Desmielinizantes do Sistema Nervoso Central/diagnóstico , Esclerose Múltipla/diagnóstico , Adolescente , Encéfalo/patologia , Criança , Pré-Escolar , Consenso , Doenças Autoimunes Desmielinizantes do Sistema Nervoso Central/patologia , Feminino , Humanos , Estimativa de Kaplan-Meier , Imageamento por Ressonância Magnética , Masculino , Esclerose Múltipla/patologia , Neuroimagem , Estudos Prospectivos , Sensibilidade e EspecificidadeRESUMO
OBJECTIVE: To describe the phenotypes and penetrance of paroxysmal kinesigenic dyskinesia (PKD), a movement disorder characterized by attacks of involuntary movements occurring after sudden movements, infantile convulsion and choreoathetosis (ICCA) syndrome, and benign familial infantile convulsions (BFIC), caused by PRRT2 mutations. METHODS: We performed clinical and genetic studies in 3 large families with ICCA, 2 smaller families with PKD, and 4 individuals with sporadic PKD. Migraine was also present in several individuals. RESULTS: We detected 3 different PRRT2 heterozygous mutations: the recurrent p.Arg217Profs*8 mutation, previously reported, was identified in 2 families with ICCA, 2 families with PKD, and one individual with sporadic PKD; one novel missense mutation (p.Ser275Phe) was detected in the remaining family with ICCA; and one novel truncating mutation (p.Arg217*) was found in one individual with sporadic PKD. In the 2 remaining individuals with sporadic PKD, PRRT2 mutations were not detected. Importantly, PRRT2 mutations did not cosegregate with febrile convulsions or with migraine. The estimated penetrance of PRRT2 mutations was 61%, if only the PKD phenotype was considered; however, if infantile convulsions were also taken into account, the penetrance was nearly complete. Considering our findings and those reported in literature, 23 PRRT2 mutations explain â¼56% of the families analyzed. CONCLUSIONS: PRRT2 mutations are the major cause of PKD or ICCA, but they do not seem to be involved in the etiology of febrile convulsions and migraine. The identification of PRRT2 as a major gene for the PKD-ICCA-BFIC spectrum allows better disease classification, molecular confirmation of the clinical diagnosis, and genetic testing and counseling.
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Discinesias/genética , Distonia/genética , Epilepsia Neonatal Benigna/genética , Proteínas de Membrana/genética , Proteínas do Tecido Nervoso/genética , Penetrância , Fenótipo , Convulsões Febris/genética , Convulsões/genética , Adolescente , Adulto , Criança , Pré-Escolar , Discinesias/complicações , Distonia/complicações , Epilepsia Neonatal Benigna/complicações , Feminino , Humanos , Masculino , Transtornos de Enxaqueca/complicações , Transtornos de Enxaqueca/genética , Mutação , Linhagem , Convulsões/complicações , Convulsões Febris/complicaçõesRESUMO
About 3-5% of all patients with multiple sclerosis experience the onset of their disease under the age of 16. A significant proportion of paediatric multiple sclerosis patients develop significant cognitive disturbances and persistent physical disability. The high relapse rate and the morbidity in the paediatric multiple sclerosis population has triggered the use of disease-modifying therapies that have been shown to reduce relapse rate, disease progression and cognitive decline in adult patients with multiple sclerosis. Hard evidence for the right treatment and its appropriate timing is scarce in paediatric multiple sclerosis. Nevertheless, expertise in this field has grown thanks to recent open-label trials and experience generated in specialized centres. In spring 2009, a first meeting was held in Rotterdam with clinicians from 11 European countries (one from Canada) that are all active in the management of paediatric multiple sclerosis. One of the aims was to generate a common view on the management of paediatric multiple sclerosis patients. The result of this meeting is presented here to help standardize treatment and to support clinicians with less experience in this field.
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Esclerose Múltipla/terapia , Adolescente , Idade de Início , Criança , Ensaios Clínicos como Assunto , Relação Dose-Resposta a Droga , Europa (Continente)/epidemiologia , Humanos , Imunossupressores/uso terapêutico , Interferon beta-1a , Interferon beta/administração & dosagem , Interferon beta/efeitos adversos , Interferon beta/uso terapêutico , Esclerose Múltipla/epidemiologia , Esclerose Múltipla/psicologia , Equipe de Assistência ao Paciente , Cooperação do Paciente , Ensaios Clínicos Controlados Aleatórios como Assunto , Recidiva , Falha de TratamentoRESUMO
OBJECTIVE: To assess if hearing loss is a feature of Joubert syndrome (JBS), one of the ciliopathies and therefore possibly associated with hearing loss. DESIGN: Retrospective case series. SETTING: University Children's Hospital. PATIENTS: Dutch patients with JBS. MAIN OUTCOME MEASURES: Audiological data. RESULTS: Data from 22 Dutch Joubert syndrome (JBS) cases (17 males, 5 females) aged 3-40 years were available. Audiological tests were successfully performed in 14 cases. Three cases (aged 17-26 years) showed very mild sensorineural hearing loss (SNHL) at different frequencies. Conductive hearing loss due to middle ear infections occurred frequently in young JBS children (6 out of 22 cases). In three cases (aged 3-13 years) the parents reported the child was hypersensitive to sound. CONCLUSION: We found no evidence for significant hearing loss in Joubert syndrome patients. However, given the compromised speech development in JBS, conductive hearing loss due to middle ear infections should be treated vigorously. SNHL at a later age cannot be excluded on the basis of our data, given the sample size. Three of the older cases showed discretely increased hearing thresholds. Analogous to the ciliopathy Bardet-Biedl syndrome, where hearing thresholds were reported to be subclinically increased in a group of adolescents patients, we recommend follow-up of JBS patients in view of the possibility of progressive, late-onset SNHL.
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Transtornos da Motilidade Ciliar/complicações , Deficiências do Desenvolvimento/complicações , Perda Auditiva Condutiva/complicações , Perda Auditiva Neurossensorial/complicações , Adolescente , Adulto , Audiometria de Tons Puros , Cerebelo/anormalidades , Criança , Pré-Escolar , Transtornos da Motilidade Ciliar/genética , Deficiências do Desenvolvimento/genética , Potenciais Evocados Auditivos do Tronco Encefálico , Feminino , Perda Auditiva Condutiva/diagnóstico , Perda Auditiva Neurossensorial/diagnóstico , Humanos , Masculino , Otite Média/complicações , Síndrome , Adulto JovemRESUMO
BACKGROUND: Fatigue is an important symptom in adult multiple sclerosis (MS) and it is likely to occur in children with MS. It is currently unknown whether children who experienced a monophasic inflammatory demyelinating event of the central nervous system in the past also suffer from fatigue. METHODS: We studied the presence and severity of fatigue in 32 children (18 boys, 14 girls) between 11-17 years old (mean: 14 years, 10 months) with a monophasic inflammatory demyelinating disease (n=22) or definite MS (n=10). This was measured with the Checklist Individual Strength. A score of >or=40 on the severity of fatigue subscale indicated the presence of severe fatigue. We also examined the relation between fatigue and depression (assessed by the Child Depression Inventory). Additionally we measured the health-related quality of life (HRQoL), using the TNO-AZL Child Quality of Life child form. We compared the scores of the MS and monophasic patients with the scores of healthy Dutch children. RESULTS: The highest scores on the fatigue scales subjective fatigue and physical activity were found in the children with MS. Only 1 of the monophasic patients suffered from severe fatigue in contrast to 4 of the MS patients. In the MS group fatigue and depression were correlated. MS patients experienced a lower HRQoL on the scales locomotor functioning, cognitive functioning and interaction with peers. CONCLUSION: The occurrence of fatigue is very rare after a monophasic inflammatory demyelinating event in the past. As expected, fatigue occurs more frequent in paediatric MS patients.
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Depressão/etiologia , Depressão/psicologia , Fadiga/etiologia , Fadiga/psicologia , Esclerose Múltipla/complicações , Adolescente , Análise de Variância , Criança , Avaliação da Deficiência , Feminino , Nível de Saúde , Humanos , Masculino , Qualidade de Vida/psicologia , Índice de Gravidade de Doença , Estatística como Assunto , Inquéritos e QuestionáriosRESUMO
We sought to identify clinical and radiologic features predicting early relapse after a diagnosis of multiple sclerosis in children. In this nationwide retrospective multicenter study in The Netherlands, we included 28 children with multiple sclerosis with onset before age 16 years. Magnetic resonance images and clinical features at the onset of disease were evaluated. The mean follow-up time was 55 months. Twenty children (71%) had a relapse during follow-up. We found that the presence of at least three of four Barkhof magnetic resonance imaging criteria at the onset of multiple sclerosis signs is predictive of early relapse after a diagnosis of multiple sclerosis in children (P<0.05).
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Encéfalo/patologia , Imageamento por Ressonância Magnética/métodos , Esclerose Múltipla Recidivante-Remitente/diagnóstico , Esclerose Múltipla Recidivante-Remitente/patologia , Adolescente , Idade de Início , Criança , Pré-Escolar , Feminino , Seguimentos , Humanos , Masculino , Países Baixos , Recidiva , Estudos Retrospectivos , Índice de Gravidade de Doença , Análise de Sobrevida , Fatores de TempoRESUMO
We report on a male patient with intra-uterine growth retardation, microcephaly, coloboma, laryngomalacia and developmental delay. Array CGH analysis revealed a 649 kb duplication on chromosome 1p34.1. Only five patients with overlapping duplications have been reported thus far. Ten known genes are located in the duplicated region, including the POMGNT1 gene encoding for O-mannose beta-1,2-N-acetylglucosaminyltransferase. This gene, mutated in muscle-eye-brain disease, might be causative for the observed phenotype in our patient.
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Transtornos Cromossômicos/genética , Cromossomos Humanos Par 1 , N-Acetilglucosaminiltransferases/genética , Coloboma/genética , Humanos , Lactente , Laringomalácia/genética , Microcefalia/genética , FenótipoRESUMO
An asymptomatic boy, aged 1.5 years, was referred with presumed liver disease because of persistently increased transaminase. Ultimately Pompe disease was confirmed, without specific abnormalities in muscle biopsy. This case demonstrates that increased transaminases do not always suggest liver disease. It is hard to determine prognosis and to decide whether enzyme replacement therapy should be started in asymptomatic patients with Pompe disease.
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Alanina Transaminase/sangue , Aspartato Aminotransferases/sangue , Glucana 1,4-alfa-Glucosidase/deficiência , Doença de Depósito de Glicogênio Tipo II/diagnóstico , Creatina Quinase/sangue , Doença de Depósito de Glicogênio Tipo II/enzimologia , Humanos , Lactente , MasculinoRESUMO
In 1998, Pierpont et al. reported on two unrelated boys with plantar lipomatosis, unusual facial phenotype, and developmental delay as a possible new MR/MCA syndrome. Here we report on a 2-year-old boy with similar manifestations: axial hypotonia in the first few months, prolonged feeding problems, moderate developmental delay, no speech development, deep palmar and plantar grooves, fat pads at the anteromedial aspect of the heels, and a distinct facial phenotype (high forehead, high anterior hairline, mild midfacial hypoplasia, remarkably narrow and upward slanted palpebral fissures, broad nasal ridge and tip, broad philtrum, bowed upper lip, "pouting" lower lip, full cheeks, and flat occiput). Brain MRI and MR spectroscopy studies showed relatively small frontal lobes, some widening of the lateral and third ventricles, and increased choline levels in the frontal white matter. Cytogenetic studies in lymphocytes and skin fibroblasts and whole genome micro-array CGH failed to show abnormalities. The present patient has a phenotype almost identical to that of the earlier reported children (Pierpont et al. [1998]: Am J Med Genet 75:18-21), which thereby validates this as a separate MR/MCA syndrome, appropriately designated Pierpont syndrome. The cause of the entity remains uncertain, the most likely etiologies being X-linked recessive or autosomal dominant genes.
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Anormalidades Múltiplas/patologia , Deficiências do Desenvolvimento/patologia , Fácies , Lipomatose/patologia , Anormalidades Múltiplas/genética , Encéfalo/anormalidades , Pré-Escolar , Face/anormalidades , Pé/patologia , Mãos/patologia , Humanos , Cariotipagem , Imageamento por Ressonância Magnética , Masculino , SíndromeAssuntos
Encefalopatias/diagnóstico , Imagem de Difusão por Ressonância Magnética , Imageamento por Ressonância Magnética , Espectroscopia de Ressonância Magnética , Ataxia/complicações , Encefalopatias/complicações , Humanos , Hidrogênio , Lactente , Masculino , Espasticidade Muscular/complicações , Convulsões/complicaçõesRESUMO
We previously identified on chromosome 6 an interval of 51 kb as the most likely interval in the HLA region for a disease-susceptibility locus for multiple sclerosis (MS). The interval was located between markers G511525 and D6S1666 and identified by the haplotype sharing statistic (HSS). The study comprised 124 patients with ancestry within the northeastern part of The Netherlands. Haplotype clustering indicated that two different ancestral haplotypes likely include a polymorphism involved in susceptibility to MS. To investigate the dominance characteristics of the MS susceptibility locus in the HLA class II region, we reanalyzed our data, performing genotype association analyses for both marker loci separately and for the two-locus haplotype. The two-locus genotype association analysis showed that in individuals who carry only one of the risk haplotypes the risk for MS is moderately increased (odds ratio (OR) 2.82; 95% confidence interval (CI) 1.50-5.31). However, in individuals carrying two risk haplotypes the risk for MS is highly increased compared with individuals who carry no risk haplotypes (OR 37.00; 95% CI 8.31-164.74). This susceptibility locus for MS seems to follow an intermediate mode of inheritance. Fitting additive, multiplicative and third power risk models to the data, the effect appears to be significantly stronger than additive.