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2.
PLoS Genet ; 7(7): e1002114, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21750680

RESUMO

Ophthalmo-acromelic syndrome (OAS), also known as Waardenburg Anophthalmia syndrome, is defined by the combination of eye malformations, most commonly bilateral anophthalmia, with post-axial oligosyndactyly. Homozygosity mapping and subsequent targeted mutation analysis of a locus on 14q24.2 identified homozygous mutations in SMOC1 (SPARC-related modular calcium binding 1) in eight unrelated families. Four of these mutations are nonsense, two frame-shift, and two missense. The missense mutations are both in the second Thyroglobulin Type-1 (Tg1) domain of the protein. The orthologous gene in the mouse, Smoc1, shows site- and stage-specific expression during eye, limb, craniofacial, and somite development. We also report a targeted pre-conditional gene-trap mutation of Smoc1 (Smoc1(tm1a)) that reduces mRNA to ∼10% of wild-type levels. This gene-trap results in highly penetrant hindlimb post-axial oligosyndactyly in homozygous mutant animals (Smoc1(tm1a/tm1a)). Eye malformations, most commonly coloboma, and cleft palate occur in a significant proportion of Smoc1(tm1a/tm1a) embryos and pups. Thus partial loss of Smoc-1 results in a convincing phenocopy of the human disease. SMOC-1 is one of the two mammalian paralogs of Drosophila Pentagone, an inhibitor of decapentaplegic. The orthologous gene in Xenopus laevis, Smoc-1, also functions as a Bone Morphogenic Protein (BMP) antagonist in early embryogenesis. Loss of BMP antagonism during mammalian development provides a plausible explanation for both the limb and eye phenotype in humans and mice.


Assuntos
Anoftalmia/genética , Proteína Morfogenética Óssea 1/antagonistas & inibidores , Mutação , Osteonectina , Síndrome de Waardenburg/genética , Animais , Proteína Morfogenética Óssea 1/genética , Coloboma/genética , Análise Mutacional de DNA , Extremidades/crescimento & desenvolvimento , Olho/crescimento & desenvolvimento , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Modelos Animais , Osteonectina/genética , Osteonectina/metabolismo , Linhagem , Sindactilia/genética , Xenopus laevis
3.
Biochim Biophys Acta ; 1812(7): 711-8, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21419220

RESUMO

Mandibuloacral dysplasia type A (MADA) is a rare disease caused by mutations in the LMNA gene encoding A type lamins. Patients affected by mandibuloacral dysplasia type A suffer from partial lipodystrophy, skin abnormalities and accelerated aging. Typical of mandibuloacral dysplasia type A is also bone resorption at defined districts including terminal phalanges, mandible and clavicles. Little is known about the biological mechanism underlying osteolysis in mandibuloacral dysplasia type A. In the reported study, we analyzed an osteoblast primary culture derived from the cervical vertebrae of a mandibuloacral dysplasia type A patient bearing the homozygous R527H LMNA mutation. Mandibuloacral dysplasia type A osteoblasts showed nuclear abnormalities typical of laminopathic cells, but they proliferated in culture and underwent differentiation upon stimulation with dexamethasone and beta-glycerophosphate. Differentiated osteoblasts showed proper production of bone mineral matrix until passage 8 in culture, suggesting a good differentiation activity. In order to evaluate whether mandibuloacral dysplasia type A osteoblast-derived factors affected osteoclast differentiation or activity, we used a conditioned medium from mandibuloacral dysplasia type A or control cultures to treat normal human peripheral blood monocytes and investigated whether they were induced to differentiate into osteoclasts. A higher osteoclast differentiation and matrix digestion rate was obtained in the presence of mandibuloacral dysplasia type A osteoblast medium with respect to normal osteoblast medium. Further, TGFbeta 2 and osteoprotegerin expression were enhanced in mandibuloacral dysplasia type A osteoblasts while the RANKL/osteoprotegerin ratio was diminished. Importantly, inhibition of TGFbeta 2 by a neutralizing antibody abolished the effect of mandibuloacral dysplasia type A conditioned medium on osteoclast differentiation. These data argue in favor of an altered bone turnover in mandibuloacral dysplasia type A, caused by upregulation of bone-derived stimulatory cytokines, which activate non-canonical differentiation stimuli. In this context, TGFbeta 2 appears as a major player in the osteolytic process that affects mandibuloacral dysplasia type A patients.


Assuntos
Acro-Osteólise/patologia , Diferenciação Celular , Osteoblastos/patologia , Osteoclastos/patologia , Acro-Osteólise/sangue , Fosfatase Alcalina/metabolismo , Sequência de Bases , Western Blotting , Células Cultivadas , Primers do DNA , Ensaio de Imunoadsorção Enzimática , Imunofluorescência , Perfilação da Expressão Gênica , Humanos , Microscopia Eletrônica
4.
Clin Dysmorphol ; 16(3): 157-161, 2007 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-17551328

RESUMO

We report an apparently healthy 5-year-old girl with multiple vertebral segmentation defects, partial fusion of some left ribs, abnormal vertebral arches, left renal agenesis, and a 'Cooley-like' hand appearance radiologically. The costovertebral defects were extensive but not contiguous, which establishes this case as being different from the Mendelian forms of spondylocostal dysostosis. The extended skeletal involvement raises the question as to how this case is classified within this heterogeneous group of disorders and we believe this might represent a new and distinct entity.


Assuntos
Anormalidades Múltiplas/patologia , Deformidades Congênitas da Mão/complicações , Deformidades Congênitas da Mão/patologia , Rim/anormalidades , Pré-Escolar , Disostoses/patologia , Feminino , Pé/diagnóstico por imagem , Deformidades Congênitas da Mão/diagnóstico por imagem , Humanos , Radiografia , Coluna Vertebral/diagnóstico por imagem
5.
Brain Dev ; 28(6): 392-4, 2006 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16376045

RESUMO

We report on an 1-day-old boy with classical lissencephaly (grade 1, according to Kato and Dobyns, 2003) associated with an extended phenotype, including dolichocephaly, and hair and nail defects. The diagnosis of lissencephaly was made in utero, allowing the rapid characterization of the phenotype at birth. Because previously reported cases were not associated with the features described in our proband, they might represent a newly identified condition.


Assuntos
Encefalopatias/patologia , Córtex Cerebral/anormalidades , Doenças do Cabelo/patologia , Doenças da Unha/patologia , Crânio/anormalidades , Encefalopatias/congênito , Encefalopatias/diagnóstico por imagem , Córtex Cerebral/diagnóstico por imagem , Doenças do Cabelo/congênito , Humanos , Recém-Nascido , Imageamento por Ressonância Magnética , Masculino , Doenças da Unha/congênito , Fenótipo , Crânio/diagnóstico por imagem , Ultrassonografia Pré-Natal
6.
Hum Vaccin Immunother ; 10(5): 1204-10, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24603089

RESUMO

Although influenza vaccination is recognized to be safe and effective, recent studies have confirmed that immunization coverage among health care workers remain generally low, especially among medical residents (MRs). Aim of the present multicenter study was to investigate attitudes and determinants associated with acceptance of influenza vaccination among Italian MRs. A survey was performed in 2012 on MRs attending post-graduate schools of 18 Italian Universities. Each participant was interviewed via an anonymous, self-administered, web-based questionnaire including questions on attitudes regarding influenza vaccination. A total of 2506 MRs were recruited in the survey and 299 (11.9%) of these stated they had accepted influenza vaccination in 2011-2012 season. Vaccinated MRs were older (P = 0.006), working in clinical settings (P = 0.048), and vaccinated in the 2 previous seasons (P<0.001 in both seasons). Moreover, MRs who had recommended influenza vaccination to their patients were significantly more compliant with influenza vaccination uptake in 2011-2012 season (P<0.001). "To avoid spreading influenza among patients" was recognized as the main reason for accepting vaccination by less than 15% of vaccinated MRs. Italian MRs seem to have a very low compliance with influenza vaccination and they seem to accept influenza vaccination as a habit that is unrelated to professional and ethical responsibility. Otherwise, residents who refuse vaccination in the previous seasons usually maintain their behaviors. Promoting correct attitudes and good practice in order to improve the influenza immunization rates of MRs could represent a decisive goal for increasing immunization coverage among health care workers of the future.


Assuntos
Atitude do Pessoal de Saúde , Coleta de Dados , Vacinas contra Influenza/uso terapêutico , Internato e Residência , Médicos , Vacinação/estatística & dados numéricos , Adulto , Coleta de Dados/métodos , Feminino , Humanos , Influenza Humana/epidemiologia , Influenza Humana/prevenção & controle , Internato e Residência/tendências , Itália/epidemiologia , Masculino , Médicos/tendências , Vacinação/tendências
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