Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 37
Filtrar
1.
Appl Environ Microbiol ; 84(9)2018 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-29500266

RESUMO

The antibiotic monensin is fed to dairy cows to increase milk production efficiency. A fraction of this monensin is excreted into the cow manure. Previous studies have found that cow manure containing monensin can negatively impact the performance of anaerobic digesters, especially upon first introduction. Few studies have examined whether the anaerobic digester microbiome can adapt to monensin during the operating time. Here, we conducted a long-term time series study of four lab-scale anaerobic digesters fed with cow manure. We examined changes in both the microbiome composition and function of the anaerobic digesters when subjected to the dairy antibiotic monensin. In our digesters, monensin was not rapidly degraded under anaerobic conditions. The two anaerobic digesters that were subjected to manure from monensin feed-dosed cows exhibited relatively small changes in microbiome composition and function due to relatively low monensin concentrations. At higher concentrations of monensin, which we dosed directly to control manure (from dairy cows without monensin), we observed major changes in the microbiome composition and function of two anaerobic digesters. A rapid introduction of monensin to one of these anaerobic digesters led to the impairment of methane production. Conversely, more gradual additions of the same concentrations of monensin to the other anaerobic digester led to the adaptation of the anaerobic digester microbiomes to the relatively high monensin concentrations. A member of the candidate OP11 (Microgenomates) phylum arose in this anaerobic digester and appeared to be redundant with certain Bacteroidetes phylum members, which previously were dominating.IMPORTANCE Monensin is a common antibiotic given to dairy cows in the United States and is partly excreted with dairy manure. An improved understanding of how monensin affects the anaerobic digester microbiome composition and function is important to prevent process failure for farm-based anaerobic digesters. This time series study demonstrates how anaerobic digester microbiomes are inert to low monensin concentrations and can adapt to relatively high monensin concentrations by redundancy in an already existing population. Therefore, our work provides further insight into the importance of microbiome redundancy in maintaining the stability of anaerobic digesters.


Assuntos
Antibacterianos/farmacologia , Esterco/microbiologia , Microbiota/efeitos dos fármacos , Monensin/farmacologia , Anaerobiose , Animais , Bactérias/metabolismo , Reatores Biológicos , Bovinos/microbiologia , Bovinos/fisiologia , Indústria de Laticínios , Digestão , Feminino , Metano/metabolismo
3.
Am J Hum Genet ; 95(6): 698-707, 2014 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-25434003

RESUMO

Mutations in components of the major spliceosome have been described in disorders with craniofacial anomalies, e.g., Nager syndrome and mandibulofacial dysostosis type Guion-Almeida. The U5 spliceosomal complex of eight highly conserved proteins is critical for pre-mRNA splicing. We identified biallelic mutations in TXNL4A, a member of this complex, in individuals with Burn-McKeown syndrome (BMKS). This rare condition is characterized by bilateral choanal atresia, hearing loss, cleft lip and/or palate, and other craniofacial dysmorphisms. Mutations were found in 9 of 11 affected families. In 8 families, affected individuals carried a rare loss-of-function mutation (nonsense, frameshift, or microdeletion) on one allele and a low-frequency 34 bp deletion (allele frequency 0.76%) in the core promoter region on the other allele. In a single highly consanguineous family, formerly diagnosed as oculo-oto-facial dysplasia, the four affected individuals were homozygous for a 34 bp promoter deletion, which differed from the promoter deletion in the other families. Reporter gene and in vivo assays showed that the promoter deletions led to reduced expression of TXNL4A. Depletion of TXNL4A (Dib1) in yeast demonstrated reduced assembly of the tri-snRNP complex. Our results indicate that BMKS is an autosomal-recessive condition, which is frequently caused by compound heterozygosity of low-frequency promoter deletions in combination with very rare loss-of-function mutations.


Assuntos
Atresia das Cóanas/genética , Surdez/congênito , Deleção de Genes , Cardiopatias Congênitas/genética , Regiões Promotoras Genéticas/genética , Ribonucleoproteína Nuclear Pequena U5/genética , Spliceossomos/genética , Alelos , Pré-Escolar , Atresia das Cóanas/diagnóstico , Surdez/diagnóstico , Surdez/genética , Exossomos/genética , Fácies , Feminino , Perfilação da Expressão Gênica , Frequência do Gene , Genes Reporter , Cardiopatias Congênitas/diagnóstico , Heterozigoto , Homozigoto , Humanos , Masculino , Mutação , Análise de Sequência com Séries de Oligonucleotídeos , Linhagem , Fenótipo , Ribonucleoproteína Nuclear Pequena U5/metabolismo , Análise de Sequência de DNA , Spliceossomos/metabolismo
4.
Am J Med Genet A ; 173(4): 1051-1055, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28328138

RESUMO

PTRH2 is an evolutionarily highly conserved mitochondrial protein that belongs to a family of peptidyl-tRNA hydrolases. Recently, patients from two consanguineous families with mutations in the PTRH2 gene were reported. Global developmental delay associated with microcephaly, growth retardation, progressive ataxia, distal muscle weakness with ankle contractures, demyelinating sensorimotor neuropathy, and sensorineural hearing loss were present in all patients, while facial dysmorphism with widely spaced eyes, exotropia, thin upper lip, proximally placed thumbs, and deformities of the fingers and toes were present in some individuals. Here, we report a new family with three siblings affected by sensorineural hearing loss and peripheral neuropathy. Autozygosity mapping followed by exome sequencing identified a previously reported homozygous missense mutation in PTRH2 (c.254A>C; p.(Gln85Pro)). Sanger sequencing confirmed that the variant segregated with the phenotype. In contrast to the previously reported patient, the affected siblings had normal intelligence, milder microcephaly, delayed puberty, myopia, and moderate insensitivity to pain. Our findings expand the clinical phenotype and further demonstrate the clinical heterogeneity related to PTRH2 variants.


Assuntos
Hidrolases de Éster Carboxílico/genética , Perda Auditiva Neurossensorial/genética , Homozigoto , Proteínas Mitocondriais/genética , Mutação de Sentido Incorreto , Doenças do Sistema Nervoso Periférico/genética , Adolescente , Sequência de Bases , Consanguinidade , Progressão da Doença , Feminino , Expressão Gênica , Heterogeneidade Genética , Perda Auditiva Neurossensorial/diagnóstico , Perda Auditiva Neurossensorial/fisiopatologia , Humanos , Masculino , Miopia/fisiopatologia , Insensibilidade Congênita à Dor/fisiopatologia , Linhagem , Doenças do Sistema Nervoso Periférico/diagnóstico , Doenças do Sistema Nervoso Periférico/fisiopatologia , Fenótipo , Puberdade Tardia/fisiopatologia , Irmãos
5.
Am J Hum Genet ; 92(2): 259-64, 2013 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-23313374

RESUMO

Urofacial syndrome (UFS) (or Ochoa syndrome) is an autosomal-recessive disease characterized by congenital urinary bladder dysfunction, associated with a significant risk of kidney failure, and an abnormal facial expression upon smiling, laughing, and crying. We report that a subset of UFS-affected individuals have biallelic mutations in LRIG2, encoding leucine-rich repeats and immunoglobulin-like domains 2, a protein implicated in neural cell signaling and tumorigenesis. Importantly, we have demonstrated that rare variants in LRIG2 might be relevant to nonsyndromic bladder disease. We have previously shown that UFS is also caused by mutations in HPSE2, encoding heparanase-2. LRIG2 and heparanase-2 were immunodetected in nerve fascicles growing between muscle bundles within the human fetal bladder, directly implicating both molecules in neural development in the lower urinary tract.


Assuntos
Glicoproteínas de Membrana/genética , Mutação/genética , Doenças Urológicas/genética , Sequência de Bases , Criança , Pré-Escolar , Análise Mutacional de DNA , Fácies , Família , Feminino , Humanos , Imuno-Histoquímica , Lactente , Masculino , Dados de Sequência Molecular , Linhagem , Bexiga Urinária/patologia , Bexiga Urinaria Neurogênica/genética , Doenças Urológicas/fisiopatologia
6.
J Am Soc Nephrol ; 26(4): 797-804, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25145936

RESUMO

Urofacial syndrome (UFS) is an autosomal recessive congenital disease featuring grimacing and incomplete bladder emptying. Mutations of HPSE2, encoding heparanase 2, a heparanase 1 inhibitor, occur in UFS, but knowledge about the HPSE2 mutation spectrum is limited. Here, seven UFS kindreds with HPSE2 mutations are presented, including one with deleted asparagine 254, suggesting a role for this amino acid, which is conserved in vertebrate orthologs. HPSE2 mutations were absent in 23 non-neurogenic neurogenic bladder probands and, of 439 families with nonsyndromic vesicoureteric reflux, only one carried a putative pathogenic HPSE2 variant. Homozygous Hpse2 mutant mouse bladders contained urine more often than did wild-type organs, phenocopying human UFS. Pelvic ganglia neural cell bodies contained heparanase 1, heparanase 2, and leucine-rich repeats and immunoglobulin-like domains-2 (LRIG2), which is mutated in certain UFS families. In conclusion, heparanase 2 is an autonomic neural protein implicated in bladder emptying, but HPSE2 variants are uncommon in urinary diseases resembling UFS.


Assuntos
Glucuronidase/genética , Sistema Urinário/fisiopatologia , Doenças Urológicas/genética , Animais , Fácies , Feminino , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Mutação , Doenças Urológicas/fisiopatologia
7.
Ann Rheum Dis ; 74(6): 1249-56, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24442880

RESUMO

OBJECTIVES: Leri's pleonosteosis (LP) is an autosomal dominant rheumatic condition characterised by flexion contractures of the interphalangeal joints, limited motion of multiple joints, and short broad metacarpals, metatarsals and phalanges. Scleroderma-like skin thickening can be seen in some individuals with LP. We undertook a study to characterise the phenotype of LP and identify its genetic basis. METHODS AND RESULTS: Whole-genome single-nucleotide polymorphism genotyping in two families with LP defined microduplications of chromosome 8q22.1 as the cause of this condition. Expression analysis of dermal fibroblasts from affected individuals showed overexpression of two genes, GDF6 and SDC2, within the duplicated region, leading to dysregulation of genes that encode proteins of the extracellular matrix and downstream players in the transforming growth factor (TGF)-ß pathway. Western blot analysis revealed markedly decreased inhibitory SMAD6 levels in patients with LP. Furthermore, in a cohort of 330 systemic sclerosis cases, we show that the minor allele of a missense SDC2 variant, p.Ser71Thr, could confer protection against disease (p<1×10(-5)). CONCLUSIONS: Our work identifies the genetic cause of LP in these two families, demonstrates the phenotypic range of the condition, implicates dysregulation of extracellular matrix homoeostasis genes in its pathogenesis, and highlights the link between TGF-ß/SMAD signalling, growth/differentiation factor 6 and syndecan-2. We propose that LP is an additional member of the growing 'TGF-ß-pathies' group of musculoskeletal disorders, which includes Myhre syndrome, acromicric dysplasia, geleophysic dysplasias, Weill-Marchesani syndromes and stiff skin syndrome. Identification of a systemic sclerosis-protective SDC2 variant lays the foundation for exploration of the role of syndecan-2 in systemic sclerosis in the future.


Assuntos
Cromossomos Humanos Par 8/genética , Duplicação Gênica , Fator 6 de Diferenciação de Crescimento/genética , Deformidades Congênitas da Mão/genética , Artropatias/congênito , Ossificação Heterotópica/genética , Escleroderma Sistêmico/genética , Sindecana-2/genética , Adulto , Idoso , Pré-Escolar , Matriz Extracelular/metabolismo , Fácies , Feminino , Fibroblastos/metabolismo , Perfilação da Expressão Gênica , Fator 6 de Diferenciação de Crescimento/metabolismo , Deformidades Congênitas da Mão/metabolismo , Deformidades Congênitas da Mão/fisiopatologia , Humanos , Lactente , Artropatias/genética , Artropatias/metabolismo , Artropatias/fisiopatologia , Masculino , Pessoa de Meia-Idade , Ossificação Heterotópica/metabolismo , Ossificação Heterotópica/fisiopatologia , Fenótipo , Transdução de Sinais , Sindecana-2/metabolismo , Fator de Crescimento Transformador beta/metabolismo , Adulto Jovem
8.
Am J Hum Genet ; 89(1): 148-53, 2011 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-21737058

RESUMO

3-M syndrome, a primordial growth disorder, is associated with mutations in CUL7 and OBSL1. Exome sequencing now identifies mutations in CCDC8 as a cause of 3-M syndrome. CCDC8 is a widely expressed gene that is transcriptionally associated to CUL7 and OBSL1, and coimmunoprecipitation indicates a physical interaction between CCDC8 and OBSL1 but not CUL7. We propose that CUL7, OBSL1, and CCDC8 are members of a pathway controlling mammalian growth.


Assuntos
Proteínas Culina/genética , Proteínas do Citoesqueleto/genética , Nanismo/genética , Deficiência Intelectual/genética , Hipotonia Muscular/genética , Linhagem Celular , Pré-Escolar , Proteínas Culina/metabolismo , Proteínas do Citoesqueleto/metabolismo , Feminino , Expressão Gênica , Homozigoto , Humanos , Lactente , Masculino , Mutação , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Coluna Vertebral/anormalidades , Fatores de Transcrição
9.
Am J Hum Genet ; 88(5): 616-20, 2011 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-21549343

RESUMO

Amelogenesis imperfecta (AI) describes a clinically and genetically heterogeneous group of disorders of biomineralization resulting from failure of normal enamel formation. AI is found as an isolated entity or as part of a syndrome, and an autosomal-recessive syndrome associating AI and gingival hyperplasia was recently reported. Using whole-exome sequencing, we identified a homozygous nonsense mutation in exon 2 of FAM20A that was not present in the Single Nucleotide Polymorphism database (dbSNP), the 1000 Genomes database, or the Centre d'Etude du Polymorphisme Humain (CEPH) Diversity Panel. Expression analyses indicated that Fam20a is expressed in ameloblasts and gingivae, providing biological plausibility for mutations in FAM20A underlying the pathogenesis of this syndrome.


Assuntos
Amelogênese Imperfeita/genética , Amelogênese Imperfeita/patologia , Proteínas do Esmalte Dentário/genética , Hiperplasia Gengival/patologia , Mutação , Ameloblastos/metabolismo , Cromossomos Humanos Par 17 , Éxons , Regulação da Expressão Gênica , Heterogeneidade Genética , Homozigoto , Humanos , Linhagem , Polimorfismo de Nucleotídeo Único , Síndrome
10.
Am J Hum Genet ; 89(5): 675-81, 2011 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-22077973

RESUMO

Say-Barber-Biesecker-Young-Simpson syndrome (SBBYSS or Ohdo syndrome) is a multiple anomaly syndrome characterized by severe intellectual disability, blepharophimosis, and a mask-like facial appearance. A number of individuals with SBBYSS also have thyroid abnormalities and cleft palate. The condition usually occurs sporadically and is therefore presumed to be due in most cases to new dominant mutations. In individuals with SBBYSS, a whole-exome sequencing approach was used to demonstrate de novo protein-truncating mutations in the highly conserved histone acetyltransferase gene KAT6B (MYST4/MORF)) in three out of four individuals sequenced. Sanger sequencing was used to confirm truncating mutations of KAT6B, clustering in the final exon of the gene in all four individuals and in a further nine persons with typical SBBYSS. Where parental samples were available, the mutations were shown to have occurred de novo. During mammalian development KAT6B is upregulated specifically in the developing central nervous system, facial structures, and limb buds. The phenotypic features seen in the Qkf mouse, a hypomorphic Kat6b mutant, include small eyes, ventrally placed ears and long first digits that mirror the human phenotype. This is a further example of how perturbation of a protein involved in chromatin modification might give rise to a multisystem developmental disorder.


Assuntos
Códon sem Sentido/genética , Hipotireoidismo Congênito/genética , Exoma/genética , Histona Acetiltransferases , Deficiência Intelectual/genética , Anormalidades Múltiplas/genética , Adulto , Animais , Blefarofimose/genética , Criança , Cromatina/metabolismo , Cromossomos Humanos Par 10/genética , Fácies , Feminino , Regulação da Expressão Gênica no Desenvolvimento , Cardiopatias Congênitas , Histona Acetiltransferases/deficiência , Histona Acetiltransferases/genética , Humanos , Mutação INDEL/genética , Instabilidade Articular , Masculino , Erros Inatos do Metabolismo/genética , Camundongos , Camundongos Transgênicos , Análise em Microsséries , Polimorfismo de Nucleotídeo Único/genética
11.
Am J Hum Genet ; 88(6): 767-777, 2011 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-21664999

RESUMO

Extreme corneal fragility and thinning, which have a high risk of catastrophic spontaneous rupture, are the cardinal features of brittle cornea syndrome (BCS), an autosomal-recessive generalized connective tissue disorder. Enucleation is frequently the only management option for this condition, resulting in blindness and psychosocial distress. Even when the cornea remains grossly intact, visual function could also be impaired by a high degree of myopia and keratoconus. Deafness is another common feature and results in combined sensory deprivation. Using autozygosity mapping, we identified mutations in PRDM5 in families with BCS. We demonstrate that regulation of expression of extracellular matrix components, particularly fibrillar collagens, by PRDM5 is a key molecular mechanism that underlies corneal fragility in BCS and controls normal corneal development and maintenance. ZNF469, encoding a zinc finger protein of hitherto undefined function, has been identified as a quantitative trait locus for central corneal thickness, and mutations in this gene have been demonstrated in Tunisian Jewish and Palestinian kindreds with BCS. We show that ZNF469 and PRDM5, two genes that when mutated cause BCS, participate in the same regulatory pathway.


Assuntos
Proteínas de Ligação a DNA/genética , Matriz Extracelular/genética , Fatores de Transcrição/genética , Criança , Análise Mutacional de DNA , Síndrome de Ehlers-Danlos/genética , Síndrome de Ehlers-Danlos/patologia , Matriz Extracelular/fisiologia , Anormalidades do Olho , Feminino , Humanos , Instabilidade Articular/congênito , Masculino , Mutação , Linhagem , Anormalidades da Pele
12.
Blood ; 120(14): 2826-35, 2012 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-22875911

RESUMO

The clinical value of serial minimal residual disease (MRD) monitoring in core binding factor (CBF) acute myeloid leukemia (AML) by quantitative RT-PCR was prospectively assessed in 278 patients [163 with t(8;21) and 115 with inv(16)] entered in the United Kingdom MRC AML 15 trial. CBF transcripts were normalized to 10(5) ABL copies. At remission, after course 1 induction chemotherapy, a > 3 log reduction in RUNX1-RUNX1T1 transcripts in BM in t(8;21) patients and a > 10 CBFB-MYH11 copy number in peripheral blood (PB) in inv(16) patients were the most useful prognostic variables for relapse risk on multivariate analysis. MRD levels after consolidation (course 3) were also informative. During follow-up, cut-off MRD thresholds in BM and PB associated with a 100% relapse rate were identified: for t(8;21) patients BM > 500 copies, PB > 100 copies; for inv(16) patients, BM > 50 copies and PB > 10 copies. Rising MRD levels on serial monitoring accurately predicted hematologic relapse. During follow-up, PB sampling was equally informative as BM for MRD detection. We conclude that MRD monitoring by quantitative RT-PCR at specific time points in CBF AML allows identification of patients at high risk of relapse and could now be incorporated in clinical trials to evaluate the role of risk directed/preemptive therapy.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Biomarcadores Tumorais/genética , Leucemia Mieloide Aguda/tratamento farmacológico , Recidiva Local de Neoplasia/diagnóstico , Neoplasia Residual/diagnóstico , Proteínas de Fusão Oncogênica/genética , Reação em Cadeia da Polimerase em Tempo Real , Adolescente , Adulto , Idoso , Cromossomos Humanos Par 21/genética , Cromossomos Humanos Par 8/genética , Subunidade alfa 2 de Fator de Ligação ao Core/genética , Feminino , Humanos , Leucemia Mieloide Aguda/mortalidade , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/genética , Recidiva Local de Neoplasia/mortalidade , Estadiamento de Neoplasias , Neoplasia Residual/genética , Neoplasia Residual/mortalidade , Prognóstico , Estudos Prospectivos , RNA Mensageiro/genética , Proteína 1 Parceira de Translocação de RUNX1 , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Medição de Risco , Taxa de Sobrevida , Translocação Genética/genética , Adulto Jovem
13.
Arthritis Rheum ; 65(8): 2161-71, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23666743

RESUMO

OBJECTIVE: Systemic lupus erythematosus (SLE) is a prototype autoimmune disease that is assumed to occur via a complex interplay of environmental and genetic factors. Rare causes of monogenic SLE have been described, providing unique insights into fundamental mechanisms of immune tolerance. The aim of this study was to identify the cause of an autosomal-recessive form of SLE. METHODS: We studied 3 siblings with juvenile-onset SLE from 1 consanguineous kindred and used next-generation sequencing to identify mutations in the disease-associated gene. We performed extensive biochemical, immunologic, and functional assays to assess the impact of the identified mutations on B cell biology. RESULTS: We identified a homozygous missense mutation in PRKCD, encoding protein kinase δ (PKCδ), in all 3 affected siblings. Mutation of PRKCD resulted in reduced expression and activity of the encoded protein PKCδ (involved in the deletion of autoreactive B cells), leading to resistance to B cell receptor- and calcium-dependent apoptosis and increased B cell proliferation. Thus, as for mice deficient in PKCδ, which exhibit an SLE phenotype and B cell expansion, we observed an increased number of immature B cells in the affected family members and a developmental shift toward naive B cells with an immature phenotype. CONCLUSION: Our findings indicate that PKCδ is crucial in regulating B cell tolerance and preventing self-reactivity in humans, and that PKCδ deficiency represents a novel genetic defect of apoptosis leading to SLE.


Assuntos
Apoptose , Linfócitos B/patologia , Lúpus Eritematoso Sistêmico/enzimologia , Lúpus Eritematoso Sistêmico/genética , Mutação de Sentido Incorreto , Proteína Quinase C-delta/deficiência , Proteína Quinase C-delta/genética , Adolescente , Adulto , Linfócitos B/imunologia , Linfócitos B/metabolismo , Proliferação de Células , Criança , Feminino , Variação Genética , Homozigoto , Humanos , Hiperplasia , Tolerância Imunológica , Lúpus Eritematoso Sistêmico/patologia , Masculino , Polimorfismo de Nucleotídeo Único , Proteína Quinase C-delta/imunologia , Adulto Jovem
14.
Lung ; 192(1): 21-5, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24232979

RESUMO

Chronic cough is increasingly being recognized as a process that has multiple initiating and perpetuating triggers. Obstructive sleep apnea has recently emerged as a possible disease that can lead to chronic cough. This review details the available clinical evidence that links these two disparate diseases and explores mechanistic bases of their relationship.


Assuntos
Tosse/epidemiologia , Apneia Obstrutiva do Sono/epidemiologia , Doença Crônica , Pressão Positiva Contínua nas Vias Aéreas , Tosse/diagnóstico , Tosse/fisiopatologia , Tosse/prevenção & controle , Humanos , Prevalência , Reflexo , Fatores de Risco , Apneia Obstrutiva do Sono/diagnóstico , Apneia Obstrutiva do Sono/fisiopatologia , Apneia Obstrutiva do Sono/terapia , Resultado do Tratamento
15.
Am J Hum Genet ; 87(3): 354-64, 2010 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-20727516

RESUMO

Band-like calcification with simplified gyration and polymicrogyria (BLC-PMG) is a rare autosomal-recessive neurological disorder showing highly characteristic clinical and neuroradiological features. Affected individuals demonstrate early-onset seizures, severe microcephaly, and developmental arrest with bilateral, symmetrical polymicrogyria (PMG) and a band of gray matter calcification on brain imaging; as such, the disorder can be considered as a "pseudo-TORCH" syndrome. By using autozygosity mapping and copy number analysis we identified intragenic deletions and mutations in OCLN in nine patients from six families with BLC-PMG. The OCLN gene encodes occludin, an integral component of tight junctions. Neuropathological analysis of an affected individual showed similarity to the mouse model of occludin deficiency with calcification predominantly associated with blood vessels. Both intracranial calcification and PMG are heterogeneous in etiology. Neuropathological and clinical studies of PMG have suggested that in utero ischemic or vascular insults may contribute to this common cortical abnormality. Tight junctions are functional in cerebral blood vessels early in fetal development and continue to play a vital role in maintenance of the blood-brain barrier during postnatal life. We provide evidence that the tight junction protein occludin (encoded by the OCLN gene) is involved in the pathogenesis of malformations of cortical development.


Assuntos
Calcinose/complicações , Calcinose/genética , Malformações do Desenvolvimento Cortical/complicações , Malformações do Desenvolvimento Cortical/genética , Proteínas de Membrana/genética , Mutação/genética , Junções Íntimas/genética , Animais , Sequência de Bases , Calcinose/líquido cefalorraquidiano , Calcinose/patologia , Córtex Cerebral/patologia , Cromossomos Humanos Par 5/genética , Consanguinidade , Análise Mutacional de DNA , Regulação da Expressão Gênica , Homozigoto , Humanos , Hibridização In Situ , Lactente , Recém-Nascido , Imageamento por Ressonância Magnética , Malformações do Desenvolvimento Cortical/líquido cefalorraquidiano , Malformações do Desenvolvimento Cortical/patologia , Proteínas de Membrana/metabolismo , Camundongos , Dados de Sequência Molecular , Ocludina , Software
16.
Am J Hum Genet ; 86(6): 963-9, 2010 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-20560210

RESUMO

Urinary voiding dysfunction in childhood, manifesting as incontinence, dysuria, and urinary frequency, is a common condition. Urofacial syndrome (UFS) is a rare autosomal recessive disease characterized by facial grimacing when attempting to smile and failure of the urinary bladder to void completely despite a lack of anatomical bladder outflow obstruction or overt neurological damage. UFS individuals often have reflux of infected urine from the bladder to the upper renal tract, with a risk of kidney damage and renal failure. Whole-genome SNP mapping in one affected individual defined an autozygous region of 16 Mb on chromosome 10q23-q24, within which a 10 kb deletion encompassing exons 8 and 9 of HPSE2 was identified. Homozygous exonic deletions, nonsense mutations, and frameshift mutations in five further unrelated families confirmed HPSE2 as the causative gene for UFS. Mutations were not identified in four additional UFS patients, indicating genetic heterogeneity. We show that HPSE2 is expressed in the fetal and adult central nervous system, where it might be implicated in controlling facial expression and urinary voiding, and also in bladder smooth muscle, consistent with a role in renal tract morphology and function. Our findings have broader implications for understanding the genetic basis of lower renal tract malformations and voiding dysfunction.


Assuntos
Fácies , Glucuronidase/genética , Doenças Urológicas/genética , Encéfalo/metabolismo , Criança , Pré-Escolar , Mapeamento Cromossômico , Cromossomos Humanos Par 10 , Feminino , Genes Recessivos , Glucuronidase/química , Glucuronidase/metabolismo , Humanos , Masculino , Modelos Moleculares , Músculos/metabolismo , Mutação , Linhagem , Síndrome , Bexiga Urinária/metabolismo
17.
Am Fam Physician ; 96(5): 328, 2017 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-28925650
18.
PLoS One ; 16(10): e0259059, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34710168

RESUMO

As safe and effective vaccines become widely available, attaining herd immunity and limiting the spread of COVID-19 will depend on individuals choosing to vaccinate-and doing so quickly enough to outpace mutations. Using online surveys conducted across six Latin American countries in January 2021, we experimentally assess messages designed to counteract informational deficiencies and collective action problems that may drive hesitancy. We first find that basic vaccine information persuades around 8% of hesitant individuals to become willing to vaccinate, reduces intended wait to vaccinate by 0.4 months, and increases willingness to encourage others to vaccinate. Rather than facilitating free riding, learning, or social conformity, additional information about others' behavior increases vaccine acceptance when respondents expect herd immunity will be achieved. Finally, priming the social approval benefits of vaccinating also increases vaccine acceptance. These results suggest that providing information and shaping social expectations and incentives could both significantly increase vaccine uptake.


Assuntos
COVID-19/psicologia , Recusa de Vacinação/psicologia , Vacinação/psicologia , COVID-19/prevenção & controle , Vacinas contra COVID-19/uso terapêutico , Conhecimentos, Atitudes e Prática em Saúde , Humanos , América Latina , Aceitação pelo Paciente de Cuidados de Saúde/psicologia , Aceitação pelo Paciente de Cuidados de Saúde/estatística & dados numéricos , Comunicação Persuasiva , SARS-CoV-2/patogenicidade , Inquéritos e Questionários , Vacinação/estatística & dados numéricos , Recusa de Vacinação/tendências , Vacinas/farmacologia
19.
NPJ Vaccines ; 6(1): 118, 2021 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-34593822

RESUMO

Herd immunity by mass vaccination offers the potential to substantially limit the continuing spread of COVID-19, but high levels of vaccine hesitancy threaten this goal. In a cross-country analysis of vaccine hesitant respondents across Latin America in January 2021, we experimentally tested how five features of mass vaccination campaigns-the vaccine's producer, efficacy, endorser, distributor, and current population uptake rate-shifted willingness to take a COVID-19 vaccine. We find that citizens preferred Western-produced vaccines, but were highly influenced by factual information about vaccine efficacy. Vaccine hesitant individuals were more responsive to vaccine messengers with medical expertise than political, religious, or media elite endorsements. Citizen trust in foreign governments, domestic leaders, and state institutions moderated the effects of the campaign features on vaccine acceptance. These findings can help inform the design of unfolding mass inoculation campaigns.

20.
Biotechnol Biofuels ; 12: 283, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31827611

RESUMO

BACKGROUND: The availability of a sensitive and robust activity assay is a prerequisite for efficient enzyme production, purification, and characterization. Here we report on a spectrophotometric assay for lytic polysaccharide monooxygenase (LPMO), which is an advancement of the previously published 2,6-dimethoxyphenol (2,6-DMP)-based LPMO assay. The new assay is based on hydrocoerulignone as substrate and hydrogen peroxide as cosubstrate and aims toward a higher sensitivity at acidic pH and a more reliable detection of LPMO in complex matrices like culture media. RESULTS: An LPMO activity assay following the colorimetric oxidation of hydrocoerulignone to coerulignone was developed. This peroxidase activity of LPMO in the presence of hydrogen peroxide can be detected in various buffers between pH 4-8. By reducing the substrate and cosubstrate concentration, the assay has been optimized for minimal autoxidation and enzyme deactivation while maintaining sensitivity. Finally, the optimized and validated LPMO assay was used to follow the recombinant expression of an LPMO in Pichia pastoris and to screen for interfering substances in fermentation media suppressing the assayed reaction. CONCLUSIONS: The biphenol hydrocoerulignone is a better substrate for LPMO than the monophenol 2,6-DMP, because of a ~ 30 times lower apparent K M value and a 160 mV lower oxidation potential. This greatly increases the measured LPMO activity when using hydrocoerulignone instead of 2,6-DMP under otherwise similar assay conditions. The improved activity allows the adaptation of the LPMO assay toward a higher sensitivity, different buffers and pH values, more stable assay conditions or to overcome low concentrations of inhibiting substances. The developed assay protocol and optimization guidelines increase the adaptability and applicability of the hydrocoerulignone assay for the production, purification, and characterization of LPMOs.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA