Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 61
Filtrar
1.
Pract Neurol ; 16(6): 458-461, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27503951

RESUMO

A previously well 16-year-old boy developed a rapid-onset hypokinetic syndrome, coupled with a radiological appearance of extensive and highly symmetrical basal ganglia and white matter change. The diagnostic process was challenging and we systematically considered potential causes. After excluding common causes of this clinico-radiological picture, we considered common disorders with this unusual radiological picture and vice versa, before finally concluding that this was a rare presentation of a rare disease. We considered the broad categories of: metabolic; toxic; infective; inflammatory, postinfective and immune-mediated; neoplastic; paraneoplastic and heredodegenerative. Long-term follow-up gave insight into the nature of the insult, confirming the monophasic course. During recovery, and following presumed secondary aberrant reinnervation, his disorder evolved from predominantly hypokinetic to hyperkinetic. Here, we explore the process of finding a 'best-fit' diagnosis: in this case, acute necrotising encephalopathy.


Assuntos
Gânglios da Base/patologia , Encefalopatias/diagnóstico , Adolescente , Humanos , Masculino , Radiografia , Doenças Raras , Síndrome
2.
J Neurol Neurosurg Psychiatry ; 85(4): 456-61, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24133290

RESUMO

BACKGROUND: Autoantibodies to glial, myelin and neuronal antigens have been reported in a range of central demyelination syndromes and autoimmune encephalopathies in children, but there has not been a systematic evaluation across the range of central nervous system (CNS) autoantibodies in childhood-acquired demyelinating syndromes (ADS). METHODS: Children under the age of 16 years with first-episode ADS were identified from a national prospective surveillance study; serum from 65 patients had been sent for a variety of diagnostic tests. Antibodies to astrocyte, myelin and neuronal antigens were tested or retested in all samples. RESULTS: Fifteen patients (23%) were positive for at least one antibody (Ab): AQ4-Ab was detected in three; two presenting with neuromyelitis optica (NMO) and one with isolated optic neuritis (ON). Myelin oligodendrocyte glycoprotein (MOG)-Ab was detected in seven; two with acute disseminated encephalomyelitis (ADEM), two with ON, one with transverse myelitis (TM) and two with clinically isolated syndrome (CIS). N-Methyl-D-Aspartate receptor (NMDAR)-Ab was found in two; one presenting with ADEM and one with ON. Voltage-gated potassium channel (VGKC)-complex antibodies were positive in three; one presenting with ADEM, one with ON and one with CIS. GlyR-Ab was detected in one patient with TM. All patients were negative for the VGKC-complex-associated proteins LGI1, CASPR2 and contactin-2. CONCLUSIONS: A range of CNS-directed autoantibodies were found in association with childhood ADS. Although these antibodies are clinically relevant when associated with the specific neurological syndromes that have been described, further studies are required to evaluate their roles and clinical relevance in demyelinating diseases.


Assuntos
Autoanticorpos/imunologia , Doenças Desmielinizantes/imunologia , Proteínas do Tecido Nervoso/imunologia , Adolescente , Autoanticorpos/sangue , Biomarcadores/sangue , Criança , Estudos de Coortes , Doenças Desmielinizantes/sangue , Doenças Desmielinizantes/diagnóstico , Feminino , Humanos , Masculino , Neuroimagem , Reino Unido
3.
Brain ; 136(Pt 2): 508-21, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23413262

RESUMO

The ß-tropomyosin gene encodes a component of the sarcomeric thin filament. Rod-shaped dimers of tropomyosin regulate actin-myosin interactions and ß-tropomyosin mutations have been associated with nemaline myopathy, cap myopathy, Escobar syndrome and distal arthrogryposis types 1A and 2B. In this study, we expand the allelic spectrum of ß-tropomyosin-related myopathies through the identification of a novel ß-tropomyosin mutation in two clinical contexts not previously associated with ß-tropomyosin. The first clinical phenotype is core-rod myopathy, with a ß-tropomyosin mutation uncovered by whole exome sequencing in a family with autosomal dominant distal myopathy and muscle biopsy features of both minicores and nemaline rods. The second phenotype, observed in four unrelated families, is autosomal dominant trismus-pseudocamptodactyly syndrome (distal arthrogryposis type 7; previously associated exclusively with myosin heavy chain 8 mutations). In all four families, the mutation identified was a novel 3-bp in-frame deletion (c.20_22del) that results in deletion of a conserved lysine at the seventh amino acid position (p.K7del). This is the first mutation identified in the extreme N-terminus of ß-tropomyosin. To understand the potential pathogenic mechanism(s) underlying this mutation, we performed both computational analysis and in vivo modelling. Our theoretical model predicts that the mutation disrupts the N-terminus of the α-helices of dimeric ß-tropomyosin, a change predicted to alter protein-protein binding between ß-tropomyosin and other molecules and to disturb head-to-tail polymerization of ß-tropomyosin dimers. To create an in vivo model, we expressed wild-type or p.K7del ß-tropomyosin in the developing zebrafish. p.K7del ß-tropomyosin fails to localize properly within the thin filament compartment and its expression alters sarcomere length, suggesting that the mutation interferes with head-to-tail ß-tropomyosin polymerization and with overall sarcomeric structure. We describe a novel ß-tropomyosin mutation, two clinical-histopathological phenotypes not previously associated with ß-tropomyosin and pathogenic data from the first animal model of ß-tropomyosin-related myopathies.


Assuntos
Lisina/genética , Doenças Musculares/diagnóstico , Doenças Musculares/genética , Deleção de Sequência , Tropomiosina/genética , Adolescente , Adulto , Sequência de Aminoácidos , Animais , Criança , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Dados de Sequência Molecular , Doenças Musculares/patologia , Tropomiosina/química , Adulto Jovem , Peixe-Zebra
4.
Brain ; 136(Pt 1): 294-303, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23365103

RESUMO

Myoclonus dystonia syndrome is a childhood onset hyperkinetic movement disorder characterized by predominant alcohol responsive upper body myoclonus and dystonia. A proportion of cases are due to mutations in the maternally imprinted SGCE gene. Previous studies have suggested that patients with SGCE mutations may have an increased rate of psychiatric disorders. We established a cohort of patients with myoclonus dystonia syndrome and SGCE mutations to determine the extent to which psychiatric disorders form part of the disease phenotype. In all, 89 patients with clinically suspected myoclonus dystonia syndrome were recruited from the UK and Ireland. SGCE was analysed using direct sequencing and for copy number variants. In those patients where no mutation was found TOR1A (GAG deletion), GCH1, THAP1 and NKX2-1 were also sequenced. SGCE mutation positive cases were systematically assessed using standardized psychiatric interviews and questionnaires and compared with a disability-matched control group of patients with alcohol responsive tremor. Nineteen (21%) probands had a SGCE mutation, five of which were novel. Recruitment of family members increased the affected SGCE mutation positive group to 27 of whom 21 (77%) had psychiatric symptoms. Obsessive-compulsive disorder was eight times more likely (P < 0.001) in mutation positive cases, compulsivity being the predominant feature (P < 0.001). Generalized anxiety disorder (P = 0.003) and alcohol dependence (P = 0.02) were five times more likely in mutation positive cases than tremor controls. SGCE mutations are associated with a specific psychiatric phenotype consisting of compulsivity, anxiety and alcoholism in addition to the characteristic motor phenotype. SGCE mutations are likely to have a pleiotropic effect in causing both motor and specific psychiatric symptoms.


Assuntos
Alcoolismo/genética , Transtornos de Ansiedade/genética , Distúrbios Distônicos/genética , Mioclonia/genética , Transtorno Obsessivo-Compulsivo/genética , Sarcoglicanas/genética , Adolescente , Adulto , Idoso , Alcoolismo/diagnóstico , Transtornos de Ansiedade/diagnóstico , Criança , Pré-Escolar , Feminino , Predisposição Genética para Doença , Humanos , Masculino , Pessoa de Meia-Idade , Mutação , Transtorno Obsessivo-Compulsivo/diagnóstico , Fenótipo , Qualidade de Vida
5.
Mult Scler ; 19(1): 76-86, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22516794

RESUMO

OBJECTIVE: Changing trends in multiple sclerosis (MS) epidemiology may first be apparent in the childhood population affected with first onset acquired demyelinating syndromes (ADSs). We aimed to determine the incidence, clinical, investigative and magnetic resonance imaging (MRI) features of childhood central nervous system ADSs in the British Isles for the first time. METHODS: We conducted a population active surveillance study. All paediatricians, and ophthalmologists (n = 4095) were sent monthly reporting cards (September 2009-September 2010). International Paediatric MS Study Group 2007 definitions and McDonald 2010 MS imaging criteria were used for acute disseminated encephalomyelitis (ADEM), clinically isolated syndrome (CIS) and neuromyelitis optica (NMO). Clinicians completed a standard questionnaire and provided an MRI copy for review. RESULTS: Card return rates were 90%, with information available for 200/222 positive notifications (90%). After exclusion of cases, 125 remained (age range 1.3-15.9), with CIS in 66.4%, ADEM in 32.0% and NMO in 1.6%. The female-to-male ratio in children older than 10 years (n = 63) was 1.52:1 (p = 0.045). The incidence of first onset ADS in children aged 1-15 years old was 9.83 per million children per year (95% confidence interval [CI] 8.18-11.71). A trend towards higher incidence rates of ADS in children of South Asian and Black ethnicity was observed compared with White children. Importantly, a number of MRI characteristics distinguished ADEM from CIS cases. Of CIS cases with contrast imaging, 26% fulfilled McDonald 2010 MS diagnostic criteria. CONCLUSIONS: We report the highest surveillance incidence rates of childhood ADS. Paediatric MS diagnosis at first ADS presentation has implications for clinical practice and clinical trial design.


Assuntos
Doenças Autoimunes Desmielinizantes do Sistema Nervoso Central/epidemiologia , Doenças Autoimunes Desmielinizantes do Sistema Nervoso Central/patologia , Adolescente , Criança , Pré-Escolar , Feminino , Humanos , Incidência , Lactente , Masculino
6.
Environ Sci Technol ; 47(12): 6440-8, 2013 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-23697787

RESUMO

A field test with a one-time emulsified vegetable oil (EVO) injection was conducted to assess the capacity of EVO to sustain uranium bioreduction in a high-permeability gravel layer with groundwater concentrations of (mM) U, 0.0055; Ca, 2.98; NO3(-), 0.11; HCO3(-), 5.07; and SO4(2-), 1.23. Comparison of bromide and EVO migration and distribution indicated that a majority of the injected EVO was retained in the subsurface from the injection wells to 50 m downgradient. Nitrate, uranium, and sulfate were sequentially removed from the groundwater within 1-2 weeks, accompanied by an increase in acetate, Mn, Fe, and methane concentrations. Due to the slow release and degradation of EVO with time, reducing conditions were sustained for approximately one year, and daily U discharge to a creek, located approximately 50 m from the injection wells, decreased by 80% within 100 days. Total U discharge was reduced by 50% over the one-year period. Reduction of U(VI) to U(IV) was confirmed by synchrotron analysis of recovered aquifer solids. Oxidants (e.g., dissolved oxygen, nitrate) flowing in from upgradient appeared to reoxidize and remobilize uranium after the EVO was exhausted as evidenced by a transient increase of U concentration above ambient values. Occasional (e.g., annual) EVO injection into a permeable Ca and bicarbonate-containing aquifer can sustain uranium bioreduction/immobilization and decrease U migration/discharge.


Assuntos
Biodegradação Ambiental , Óleos de Plantas/química , Urânio/química , Verduras/química , Elétrons , Ferro/química , Manganês/química , Metano/química
7.
Dev Med Child Neurol ; 55(4): 327-34, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23363396

RESUMO

AIM: To define better the phenotype and genotype of familial and sporadic cases of paroxysmal kinesigenic dyskinesia (PKD) caused by mutations in the PRRT2 gene presenting in the paediatric age group. METHOD: We report the detailed clinical and molecular genetic features of 11 patients (six females, five males) with childhood-onset PRRT2-mutation-positive PKD. RESULTS: Mean age at disease onset was 8 years 7.5 months (range 5-11y), and clinical presentation was characterized by daily short paroxysmal episodes of dystonia/dyskinesia. Most patients also had non-kinesigenic attacks in addition to the classical movement-induced paroxysmal episodes. One family demonstrated great phenotypic variability with PKD, infantile convulsions, and/or hemiplegic migraine affecting different family members with the same mutation. All patients in whom antiepileptics (carbamazepine/phenytoin) were tried showed a dramatic improvement with complete abolition of dyskinetic episodes. INTERPRETATION: Our case series provides a detailed clinical description of patients with PRRT2-PKD, and reports a spectrum of disease-causing mutations, thereby expanding both the clinical phenotype and mutation spectrum of disease.


Assuntos
Discinesias/genética , Epilepsia Neonatal Benigna/genética , Proteínas de Membrana/genética , Transtornos dos Movimentos/genética , Mutação , Proteínas do Tecido Nervoso/genética , Convulsões/genética , Adolescente , Adulto , Idade de Início , Criança , Pré-Escolar , Códon sem Sentido , Estudos de Coortes , Feminino , Mutação da Fase de Leitura , Humanos , Masculino , Pessoa de Meia-Idade , Enxaqueca com Aura/genética , Mutação de Sentido Incorreto , Fenótipo , Reino Unido , Adulto Jovem
8.
Appl Environ Microbiol ; 78(17): 6078-86, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22729539

RESUMO

Anthropogenic sources of lead contamination in soils include mining and smelting activities, effluents and wastes, agricultural pesticides, domestic garbage dumps, and shooting ranges. While Pb is typically considered relatively insoluble in the soil environment, some fungi may potentially contribute to mobilization of heavy metal cations by means of secretion of low-molecular-weight organic acids (LMWOAs). We sought to better understand the potential for metal mobilization within an indigenous fungal community at an abandoned shooting range in Oak Ridge, TN, where soil Pb contamination levels ranged from 24 to >2,700 mg Pb kg dry soil(-1). We utilized culture-based assays to determine organic acid secretion and Pb-carbonate dissolution of a diverse collection of soil fungal isolates derived from the site and verified isolate distribution patterns within the community by 28S rRNA gene analysis of whole soils. The fungal isolates examined included both ascomycetes and basidiomycetes that excreted high levels (up to 27 mM) of a mixture of LMWOAs, including oxalic and citric acids, and several isolates demonstrated a marked ability to dissolve Pb-carbonate at high concentrations up to 10.5 g liter(-1) (18.5 mM) in laboratory assays. Fungi within the indigenous community of these highly Pb-contaminated soils are capable of LMWOA secretion at levels greater than those of well-studied model organisms, such as Aspergillus niger. Additionally, these organisms were found in high relative abundance (>1%) in some of the most heavily contaminated soils. Our data highlight the need to understand more about autochthonous fungal communities at Pb-contaminated sites and how they may impact Pb biogeochemistry, solubility, and bioavailability, thus consequently potentially impacting human and ecosystem health.


Assuntos
Biodiversidade , Ácidos Carboxílicos/metabolismo , Fungos/classificação , Fungos/metabolismo , Chumbo/metabolismo , Microbiologia do Solo , Poluentes do Solo/metabolismo , Análise por Conglomerados , DNA Fúngico/química , DNA Fúngico/genética , DNA Ribossômico/química , DNA Ribossômico/genética , Fungos/genética , Fungos/isolamento & purificação , Genes de RNAr , Humanos , Dados de Sequência Molecular , Filogenia , RNA Fúngico/genética , RNA Ribossômico 28S/genética , Análise de Sequência de DNA , Tennessee
9.
Dev Med Child Neurol ; 54(6): 569-74, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22574627

RESUMO

AIM: To describe the clinical and radiological features of four new families with a childhood presentation of COL4A1 mutation. METHOD: We retrospectively reviewed the clinical presentation. Investigations included radiological findings and COL4A1 mutation analysis of the four cases. Affected family members were identified. COL4A1 mutation analysis was performed in all index cases and, where possible, in affected family members. RESULTS: The three male and one female index cases presented with recurrent childhood-onset stroke, infantile hemiplegia/spastic quadriplegia, and infantile spasms. Additional features such as congenital cataracts and anterior segment dysgenesis were present. Microcephaly and developmental delay/learning difficulties were present in three cases. Three cases had one or more family member affected in multiple generations, with a total of 11 such individuals identified. The clinical features showed a wide intrafamilial variation. Magnetic resonance imaging (MRI) showed bilateral white matter change in all cases, except in one mutation-positive family member. Unilateral or bilateral porencephaly was present in cases with infantile hemiplegia, and a diagnosis of clinical stroke was supported by the presence of intracerebral haemorrhage. The age at diagnosis was between 1 year and 6 years for the children with presentation in infancy and 12 months after stroke in a 14-year-old male. Three new pathogenic mutations were identified in the COL4A1 gene. INTERPRETATION: COL4A1 mutations can present in children with infantile hemiplegia/quadriplegia, stroke or epilepsy, and a motor disorder. The presence of eye features and white matter change on MRI in childhood can help point towards the diagnosis. Once the diagnosis is made, a careful search can identify affected family members.


Assuntos
Encefalopatias/genética , Colágeno Tipo IV/genética , Hemiplegia/genética , Mutação/genética , Adolescente , Encéfalo/patologia , Encefalopatias/patologia , Criança , Pré-Escolar , Anormalidades do Olho/genética , Saúde da Família , Feminino , Hemiplegia/patologia , Humanos , Lactente , Imageamento por Ressonância Magnética , Masculino , Porencefalia , Estudos Retrospectivos
10.
Appl Environ Microbiol ; 77(11): 3860-9, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21498771

RESUMO

A pilot-scale system was established to examine the feasibility of in situ U(VI) immobilization at a highly contaminated aquifer (U.S. DOE Integrated Field Research Challenge site, Oak Ridge, TN). Ethanol was injected intermittently as an electron donor to stimulate microbial U(VI) reduction, and U(VI) concentrations fell to below the Environmental Protection Agency drinking water standard (0.03 mg liter(-1)). Microbial communities from three monitoring wells were examined during active U(VI) reduction and maintenance phases with GeoChip, a high-density, comprehensive functional gene array. The overall microbial community structure exhibited a considerable shift over the remediation phases examined. GeoChip-based analysis revealed that Fe(III)-reducing bacterial (FeRB), nitrate-reducing bacterial (NRB), and sulfate-reducing bacterial (SRB) functional populations reached their highest levels during the active U(VI) reduction phase (days 137 to 370), in which denitrification and Fe(III) and sulfate reduction occurred sequentially. A gradual decrease in these functional populations occurred when reduction reactions stabilized, suggesting that these functional populations could play an important role in both active U(VI) reduction and maintenance of the stability of reduced U(IV). These results suggest that addition of electron donors stimulated the microbial community to create biogeochemical conditions favorable to U(VI) reduction and prevent the reduced U(IV) from reoxidation and that functional FeRB, SRB, and NRB populations within this system played key roles in this process.


Assuntos
Bactérias/classificação , Bactérias/crescimento & desenvolvimento , Biodegradação Ambiental , Biodiversidade , Microbiologia do Solo , Poluentes Radioativos do Solo/metabolismo , Urânio/metabolismo , Bactérias/metabolismo , Etanol/metabolismo , Compostos Férricos/metabolismo , Análise em Microsséries , Nitratos/metabolismo , Sulfatos/metabolismo , Estados Unidos
11.
BMC Pediatr ; 11: 68, 2011 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-21798048

RESUMO

BACKGROUND: There is evidence that at least 5% of Multiple sclerosis (MS) cases manifest in childhood. Children with MS present with a demyelinating episode involving single or multiple symptoms prior to developing a second event (usually within two years) to then meet criteria for diagnosis. There is evidence from adult cohorts that the incidence and sex ratios of MS are changing and that children of immigrants have a higher risk for developing MS. A paediatric population should reflect the vanguard of such changes and may reflect trends yet to be observed in adult cohorts. Studying a paediatric population from the first demyelinating event will allow us to test these hypotheses, and may offer further valuable insights into the genetic and environmental interactions in the pathogenesis of MS. METHODS/DESIGN: The Paediatric UK Demyelinating Disease Longitudinal Study (PUDDLS) is a prospective longitudinal observational study which aims to determine the natural history, predictors and outcomes of childhood CNS inflammatory demyelinating diseases. PUDDLS will involve centres in the UK, and will establish a cohort of children affected with a first CNS inflammatory demyelinating event for long-term follow up by recruiting for approximately 5 years. PUDDLS will also establish a biological sample archive (CSF, serum, and DNA), allowing future hypothesis driven research. For example, the future discovery of a biomarker will allow validation within this dataset for the evaluation of novel biomarkers. Patients will also be requested to consent to be contacted in the future. A secondary aim is to collaborate internationally with the International Paediatric Multiple Sclerosis Study Group when future collaborative studies are proposed, whilst sharing a minimal anonymised dataset. PUDDLS is the second of two jointly funded studies. The first (UCID-SS) is an epidemiological surveillance study that already received ethical approvals, and started on the 1st September 2009. There is no direct patient involvement, and UCID-SS aims to determine the UK and Ireland incidence of CNS inflammatory demyelinating disorders in children under 16 years. DISCUSSION: A paediatric population should reflect the vanguard of MS epidemiological changes and may reflect trends yet to be observed in adult MS cohorts. The restricted window between clinical expression of disease and exposure to environmental factors in children offers a unique research opportunity. Studying a paediatric population from the first demyelinating event will allow us to investigate the changing epidemiology of MS, and may offer further valuable insights into the genetic and environmental interactions in the pathogenesis of MS.


Assuntos
Doenças Desmielinizantes/diagnóstico , Doenças Desmielinizantes/fisiopatologia , Esclerose Múltipla/fisiopatologia , Biomarcadores/análise , Criança , Efeitos Psicossociais da Doença , Doenças Desmielinizantes/complicações , Doenças Desmielinizantes/tratamento farmacológico , Diagnóstico Diferencial , Progressão da Doença , Diagnóstico Precoce , Humanos , Estudos Longitudinais , Esclerose Múltipla/diagnóstico , Esclerose Múltipla/tratamento farmacológico , Esclerose Múltipla/etiologia , Estudos Prospectivos , Qualidade de Vida , Reino Unido/epidemiologia
12.
Appl Environ Microbiol ; 76(10): 3244-54, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-20305024

RESUMO

In terrestrial subsurface environments where nitrate is a critical groundwater contaminant, few cultivated representatives are available to verify the metabolism of organisms that catalyze denitrification. In this study, five species of denitrifying bacteria from three phyla were isolated from subsurface sediments exposed to metal radionuclide and nitrate contamination as part of the U.S. Department of Energy's Oak Ridge Integrated Field Research Challenge (OR-IFRC). Isolates belonged to the genera Afipia and Hyphomicrobium (Alphaproteobacteria), Rhodanobacter (Gammaproteobacteria), Intrasporangium (Actinobacteria), and Bacillus (Firmicutes). Isolates from the phylum Proteobacteria were complete denitrifiers, whereas the Gram-positive isolates reduced nitrate to nitrous oxide. rRNA gene analyses coupled with physiological and genomic analyses suggest that bacteria from the genus Rhodanobacter are a diverse population of denitrifiers that are circumneutral to moderately acidophilic, with a high relative abundance in areas of the acidic source zone at the OR-IFRC site. Based on genome analysis, Rhodanobacter species contain two nitrite reductase genes and have not been detected in functional-gene surveys of denitrifying bacteria at the OR-IFRC site. Nitrite and nitrous oxide reductase gene sequences were recovered from the isolates and from the terrestrial subsurface by designing primer sets mined from genomic and metagenomic data and from draft genomes of two of the isolates. We demonstrate that a combination of cultivation and genomic and metagenomic data is essential to the in situ characterization of denitrifiers and that current PCR-based approaches are not suitable for deep coverage of denitrifiers. Our results indicate that the diversity of denitrifiers is significantly underestimated in the terrestrial subsurface.


Assuntos
Bactérias/genética , Bactérias/isolamento & purificação , Exposição Ambiental , Sedimentos Geológicos/microbiologia , Sequência de Aminoácidos , Bactérias/classificação , Bactérias/efeitos dos fármacos , Bactérias/metabolismo , Sequência de Bases , Genes de RNAr/genética , Variação Genética , Genoma Bacteriano/genética , Genótipo , Metagenômica , Dados de Sequência Molecular , Nitratos/metabolismo , Nitratos/toxicidade , Nitrito Redutases/genética , Nitrito Redutases/metabolismo , Nitrogênio/metabolismo , Oxirredutases/genética , Fenótipo , Filogenia , Radioisótopos/toxicidade , Alinhamento de Sequência , Poluentes do Solo/toxicidade
13.
Appl Environ Microbiol ; 76(20): 6778-86, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20729318

RESUMO

Massively parallel sequencing has provided a more affordable and high-throughput method to study microbial communities, although it has mostly been used in an exploratory fashion. We combined pyrosequencing with a strict indicator species statistical analysis to test if bacteria specifically responded to ethanol injection that successfully promoted dissimilatory uranium(VI) reduction in the subsurface of a uranium contamination plume at the Oak Ridge Field Research Center in Tennessee. Remediation was achieved with a hydraulic flow control consisting of an inner loop, where ethanol was injected, and an outer loop for flow-field protection. This strategy reduced uranium concentrations in groundwater to levels below 0.126 µM and created geochemical gradients in electron donors from the inner-loop injection well toward the outer loop and downgradient flow path. Our analysis with 15 sediment samples from the entire test area found significant indicator species that showed a high degree of adaptation to the three different hydrochemical-created conditions. Castellaniella and Rhodanobacter characterized areas with low pH, heavy metals, and low bioactivity, while sulfate-, Fe(III)-, and U(VI)-reducing bacteria (Desulfovibrio, Anaeromyxobacter, and Desulfosporosinus) were indicators of areas where U(VI) reduction occurred. The abundance of these bacteria, as well as the Fe(III) and U(VI) reducer Geobacter, correlated with the hydraulic connectivity to the substrate injection site, suggesting that the selected populations were a direct response to electron donor addition by the groundwater flow path. A false-discovery-rate approach was implemented to discard false-positive results by chance, given the large amount of data compared.


Assuntos
Bactérias/classificação , Bactérias/genética , Biodiversidade , Microbiologia Ambiental , Metagenoma , Sulfatos/metabolismo , Urânio/metabolismo , Bactérias/metabolismo , Análise por Conglomerados , DNA Bacteriano/química , DNA Bacteriano/genética , DNA Ribossômico/química , DNA Ribossômico/genética , Sequenciamento de Nucleotídeos em Larga Escala , Dados de Sequência Molecular , Oxirredução , Filogenia , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Poluentes Radioativos do Solo/metabolismo , Tennessee
14.
Dev Med Child Neurol ; 52(5): 489-93, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-20187890

RESUMO

We report two sisters with extensive bilateral periventricular haemorrhagic infarction (PVHI) causing cerebral palsy (CP). The older sister presented at 20 months with cortical visual blindness, spastic diplegia, and purpura fulminans. The younger sister presented aged 3 days old with apnoeas and multifocal seizures. She subsequently had global developmental delay, cortical visual blindness, spastic quadriplegia, epilepsy, and purpura fulminans at age 2 years. Neuroimaging of both siblings showed bilateral PVHI consistent with bilateral cerebral intramedullary venous thrombosis occurring at under 28 weeks' gestation for the older sister and around time of birth for the younger sister. At latest follow-up, the older sister (13y) has spastic diplegia at Gross Motor Function Classification System (GMFCS) level II, and the younger sister (10y) has spastic quadriplegia at GMFCS level IV. Both sisters showed partial quantitative reduction in plasma protein C antigen and severe qualitative reduction in plasma protein C anticoagulant activity. They were heterozygous for two independent mutations in the protein C gene (PROC). There was no other risk factor for CP. To our knowledge, this is the first family reported with compound heterozygous PROC mutations as the likely genetic cause of familial CP. This report adds to the list of known monogenic causes of CP.


Assuntos
Paralisia Cerebral/genética , Ventrículos Cerebrais/patologia , Heterozigoto , Mutação , Proteína C/genética , Irmãos , Cegueira Cortical/etiologia , Cegueira Cortical/fisiopatologia , Hemorragia Cerebral/complicações , Hemorragia Cerebral/genética , Hemorragia Cerebral/patologia , Infarto Cerebral/complicações , Infarto Cerebral/genética , Infarto Cerebral/patologia , Paralisia Cerebral/etiologia , Paralisia Cerebral/patologia , Paralisia Cerebral/fisiopatologia , Feminino , Humanos , Lactente , Recém-Nascido , Imageamento por Ressonância Magnética , Proteína C/imunologia , Fatores de Risco , Índice de Gravidade de Doença
15.
Environ Microbiol ; 11(10): 2611-26, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19624708

RESUMO

A pilot-scale system was established for in situ biostimulation of U(VI) reduction by ethanol addition at the US Department of Energy's (DOE's) Field Research Center (Oak Ridge, TN). After achieving U(VI) reduction, stability of the bioreduced U(IV) was evaluated under conditions of (i) resting (no ethanol injection), (ii) reoxidation by introducing dissolved oxygen (DO), and (iii) reinjection of ethanol. GeoChip, a functional gene array with probes for N, S and C cycling, metal resistance and contaminant degradation genes, was used for monitoring groundwater microbial communities. High diversity of all major functional groups was observed during all experimental phases. The microbial community was extremely responsive to ethanol, showing a substantial change in community structure with increased gene number and diversity after ethanol injections resumed. While gene numbers showed considerable variations, the relative abundance (i.e. percentage of each gene category) of most gene groups changed little. During the reoxidation period, U(VI) increased, suggesting reoxidation of reduced U(IV). However, when introduction of DO was stopped, U(VI) reduction resumed and returned to pre-reoxidation levels. These findings suggest that the community in this system can be stimulated and that the ability to reduce U(VI) can be maintained by the addition of electron donors. This biostimulation approach may potentially offer an effective means for the bioremediation of U(VI)-contaminated sites.


Assuntos
Bactérias/crescimento & desenvolvimento , Bactérias/metabolismo , Biodiversidade , Urânio/metabolismo , Microbiologia da Água , Bactérias/genética , Biodegradação Ambiental , DNA Bacteriano/análise , DNA Bacteriano/genética , Etanol/metabolismo , Genes Bacterianos , Análise de Sequência com Séries de Oligonucleotídeos , Oxirredução , Oxigênio/metabolismo , Filogenia , Poluentes Radioativos da Água/metabolismo
16.
Genet Med ; 11(3): 210-9, 2009 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19287243

RESUMO

PURPOSE: A clinical trial was conducted to evaluate the safety and efficacy of alglucosidase alfa in infants and children with advanced Pompe disease. METHODS: Open-label, multicenter study of IV alglucosidase alfa treatment in 21 infants 3-43 months old (median 13 months) with minimal acid alpha-glucosidase activity and abnormal left ventricular mass index by echocardiography. Patients received IV alglucosidase alfa every 2 weeks for up to 168 weeks (median 120 weeks). Survival results were compared with an untreated reference cohort. RESULTS: At study end, 71% (15/21) of patients were alive and 44% (7/16) of invasive-ventilator free patients remained so. Compared with the untreated reference cohort, alglucosidase alfa reduced the risk of death by 79% (P < 0.001) and the risk of invasive ventilation by 58% (P = 0.02). Left ventricular mass index improved or remained normal in all patients evaluated beyond 12 weeks; 62% (13/21) achieved new motor milestones. Five patients were walking independently at the end of the study and 86% (18/21) gained functional independence skills. Overall, 52% (11/21) of patients experienced infusion-associated reactions; 95% (19/20) developed IgG antibodies to recombinant human lysosomal acid alpha-glucosidase; no patients withdrew from the study because of safety concerns. CONCLUSIONS: In this population of infants with advanced disease, biweekly infusions with alglucosidase alfa prolonged survival and invasive ventilation-free survival. Treatment also improved indices of cardiomyopathy, motor skills, and functional independence.


Assuntos
Doença de Depósito de Glicogênio Tipo II/tratamento farmacológico , alfa-Glucosidases/uso terapêutico , Estatura , Peso Corporal , Pré-Escolar , Tosse/induzido quimicamente , Ecocardiografia , Ensaio de Imunoadsorção Enzimática , Feminino , Glicogênio/metabolismo , Doença de Depósito de Glicogênio Tipo II/metabolismo , Doença de Depósito de Glicogênio Tipo II/fisiopatologia , Humanos , Imunoglobulina G/sangue , Lactente , Estimativa de Kaplan-Meier , Masculino , Músculo Esquelético/efeitos dos fármacos , Músculo Esquelético/metabolismo , Dermatopatias/induzido quimicamente , Fatores de Tempo , Resultado do Tratamento , alfa-Glucosidases/efeitos adversos , alfa-Glucosidases/imunologia
17.
Mult Scler ; 15(12): 1525-7, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19965514

RESUMO

In clinical practice it is not uncommon for patients with adrenomyeloneuropathy or female carriers of adrenoleucodystrophy to have a presenting history and examination compatible with multiple sclerosis. This suggests that there may be an under-diagnosis of adrenoleucodystrophy and its variants in the multiple sclerosis population. We measured levels of very long chain fatty acids, which are typically elevated in the plasma of patients with adrenoleucodystrophy, in a large cohort of patients diagnosed clinically with multiple sclerosis. We tested serum samples from patients with either a first degree relative with multiple sclerosis or those with a primary progressive phenotype. No elevations in very long chain fatty acids were found in the cohort. This study suggests that the number of cases of adrenomyeloneuropathy or adrenoleucodystrophy amongst patients diagnosed clinically with multiple sclerosis is likely to be extremely low. This has important diagnostic implications.


Assuntos
Adrenoleucodistrofia/sangue , Ácidos Graxos/sangue , Esclerose Múltipla Crônica Progressiva/sangue , Esclerose Múltipla/sangue , Adrenoleucodistrofia/genética , Adulto , Biomarcadores/sangue , Feminino , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Esclerose Múltipla/genética , Esclerose Múltipla Crônica Progressiva/genética , Linhagem , Fenótipo
18.
Epilepsia ; 50(6): 1608-11, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19243422

RESUMO

We investigate the clinical outcome from stimulation of the mamillothalamic tract in two patients with intractable epilepsy secondary to hypothalamic hamartomas. One patient has a left-sided and the other a right-sided tumor. Both patients presented with a history of gelastic and complex partial seizures resistant to multiple antiepileptic drugs. Both patients underwent insertion of a single deep brain-stimulating electrode ipsilateral to the site of the tumor, lying adjacent to the mamillothalamic tract. Postoperatively they both had a significant reduction in seizure frequency, with one patient being seizure free for the last 10 months. An improvement in mood was reported by the patient's primary carers and demonstrated on quality of life questionnaires.


Assuntos
Estimulação Encefálica Profunda/métodos , Hamartoma/terapia , Doenças Hipotalâmicas/terapia , Corpos Mamilares/fisiologia , Convulsões/terapia , Tálamo/fisiologia , Adolescente , Eletroencefalografia , Feminino , Hamartoma/complicações , Hamartoma/patologia , Humanos , Doenças Hipotalâmicas/complicações , Doenças Hipotalâmicas/patologia , Imageamento por Ressonância Magnética/métodos , Masculino , Vias Neurais/fisiologia , Testes Neuropsicológicos , Convulsões/etiologia , Convulsões/patologia , Fatores de Tempo
19.
Neuromuscul Disord ; 18(1): 52-8, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17825555

RESUMO

Pontocerebellar hypoplasia type 2, an autosomal recessive neurodegeneration with prenatal onset, is characterised by progressive microcephaly and chorea/dystonia and has not previously been associated with muscular involvement. The gene associated with PCH-2 is unknown. An episode of rhabdomyolysis is reported in two non-related children with PCH-2, fatal in one, precipitated by intercurrent disease. Muscle biopsies in two other PCH-2 patients, and in one rhabdomyolysis patient whose biopsy antedated this complication showed areas of myofibrillar disruption or necrosis. Postmortem muscle sampled in another case without neuromuscular symptoms revealed focal necrosis, regenerating small fibres and upregulation of HLA-ABC. Random serum creatine kinase values in six other PCH-2 patients without clinical signs of neuromuscular involvement were increased in four. Collected data provide preliminary evidence of a subclinical myopathy associated with PCH-2.


Assuntos
Cerebelo/anormalidades , Músculo Esquelético/patologia , Atrofias Olivopontocerebelares/complicações , Ponte/anormalidades , Rabdomiólise/patologia , Adulto , Pré-Escolar , Transtornos Cromossômicos/genética , Transtornos Cromossômicos/patologia , Transtornos Cromossômicos/fisiopatologia , Creatina Quinase/sangue , Feminino , Genes Recessivos/genética , Antígenos HLA/análise , Antígenos HLA/metabolismo , Humanos , Lactente , Recém-Nascido , Masculino , Microscopia Eletrônica de Transmissão , Fibras Musculares Esqueléticas/metabolismo , Fibras Musculares Esqueléticas/patologia , Músculo Esquelético/metabolismo , Músculo Esquelético/fisiopatologia , Necrose/genética , Necrose/patologia , Necrose/fisiopatologia , Atrofias Olivopontocerebelares/patologia , Atrofias Olivopontocerebelares/fisiopatologia , Rabdomiólise/genética , Rabdomiólise/fisiopatologia
20.
Appl Environ Microbiol ; 74(12): 3718-29, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18456853

RESUMO

Microbial enumeration, 16S rRNA gene clone libraries, and chemical analysis were used to evaluate the in situ biological reduction and immobilization of uranium(VI) in a long-term experiment (more than 2 years) conducted at a highly uranium-contaminated site (up to 60 mg/liter and 800 mg/kg solids) of the U.S. Department of Energy in Oak Ridge, TN. Bioreduction was achieved by conditioning groundwater above ground and then stimulating growth of denitrifying, Fe(III)-reducing, and sulfate-reducing bacteria in situ through weekly injection of ethanol into the subsurface. After nearly 2 years of intermittent injection of ethanol, aqueous U levels fell below the U.S. Environmental Protection Agency maximum contaminant level for drinking water and groundwater (<30 microg/liter or 0.126 microM). Sediment microbial communities from the treatment zone were compared with those from a control well without biostimulation. Most-probable-number estimations indicated that microorganisms implicated in bioremediation accumulated in the sediments of the treatment zone but were either absent or in very low numbers in an untreated control area. Organisms belonging to genera known to include U(VI) reducers were detected, including Desulfovibrio, Geobacter, Anaeromyxobacter, Desulfosporosinus, and Acidovorax spp. The predominant sulfate-reducing bacterial species were Desulfovibrio spp., while the iron reducers were represented by Ferribacterium spp. and Geothrix spp. Diversity-based clustering revealed differences between treated and untreated zones and also within samples of the treated area. Spatial differences in community structure within the treatment zone were likely related to the hydraulic pathway and to electron donor metabolism during biostimulation.


Assuntos
Bactérias/classificação , Bactérias/genética , Biodegradação Ambiental , Biodiversidade , Sedimentos Geológicos/microbiologia , Urânio/metabolismo , Bactérias/isolamento & purificação , Análise por Conglomerados , Contagem de Colônia Microbiana , DNA Bacteriano/química , DNA Bacteriano/genética , DNA Ribossômico/química , DNA Ribossômico/genética , Etanol/metabolismo , Genes de RNAr , Dados de Sequência Molecular , Filogenia , RNA Bacteriano/genética , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Homologia de Sequência do Ácido Nucleico , Estados Unidos
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA