RESUMO
The homeobox gene Prox1 is crucial for mammalian lymphatic vascular development. In the absence of Prox1, lymphatic endothelial cells (LECs) are not specified. The maintenance of LEC identity also requires the constant expression of Prox1. However, the mechanisms controlling the expression of this gene in LECs remain poorly understood. The SRY-related gene Sox18 is required to induce Prox1 expression in venous LEC progenitors. Although Sox18 is also expressed in embryonic arteries, these vessels do not express Prox1, nor do they give rise to LECs. This finding suggests that some venous endothelial cell-specific factor is required for the activation of Prox1. Here we demonstrate that the nuclear hormone receptor Coup-TFII is necessary for the activation of Prox1 in embryonic veins by directly binding a conserved DNA domain in the regulatory region of Prox1. In addition, we show that the direct interaction between nuclear hormone receptors and Prox1 is also necessary for the maintenance of Prox1 expression during early stages of LEC specification and differentiation.
Assuntos
Fator II de Transcrição COUP/metabolismo , Células Endoteliais/metabolismo , Regulação da Expressão Gênica no Desenvolvimento , Proteínas de Homeodomínio/metabolismo , Proteínas Supressoras de Tumor/metabolismo , Animais , Fator II de Transcrição COUP/genética , Diferenciação Celular , Linhagem Celular , Células Cultivadas , Células Endoteliais/citologia , Deleção de Genes , Proteínas de Homeodomínio/genética , Humanos , Camundongos , Proteínas Supressoras de Tumor/genética , Veias/embriologiaRESUMO
BACKGROUND: Cystathionine beta-synthase (CBS) deficiency is the most common cause of homocystinuria. However, no data are available concerning the molecular basis of this disease in Brazilian populations. METHODS: We studied 14 Brazilian patients from 11 unrelated families using a combined screening approach, involving restriction analysis, single-strand conformational polymorphism (SSCP) scanning, and sequencing. RESULTS: All patients presented homocysteine levels higher than 200 mumol/l before the beginning of treatment. The most common CBS gene mutations, p.G307S (c.919G > A) and p.I278T (c.833T > C), were evaluated and the allele c.919A was not found. One allele with the c.844 ins68 (4.5%) in the CBS gene was found. Three families (6 patients) presented the allele c.833 C (13.6%), without the insertion in the heterozygous state. SSCP scanning and sequencing showed 3 alleles p.T191M (13.64%) in 2 families. One allele with a novel mutation was found in exon 4 (c.168T > A) of the CBS gene (4.5%). We also analyzed c.677C > T and c.1298A > C polymorphisms in the methylenetetrahydrofolate reductase (MTHFR) gene and the 2756A > G polymorphism in the methionine synthase (MTR) gene. The frequencies of mutated alleles were: 50% c.677T and 18.2% c.1298C for MTHFR, and 27.3% c.2756G for MTR. CONCLUSION: In spite of the high level of racial mixing in the country, Brazilian homocystinuric patients did not present a high prevalence of the most common mutations described in the literature.
Assuntos
Homocistinúria/sangue , Homocistinúria/genética , 5-Metiltetra-Hidrofolato-Homocisteína S-Metiltransferase/genética , Adolescente , Adulto , Alelos , Brasil , Criança , Pré-Escolar , Cistationina beta-Sintase/deficiência , Cistationina beta-Sintase/genética , Éxons/genética , Feminino , Homocisteína/sangue , Homocistinúria/enzimologia , Humanos , Masculino , Metilenotetra-Hidrofolato Redutase (NADPH2)/genética , Mutação/genética , Polimorfismo Conformacional de Fita SimplesRESUMO
UNLABELLED: We ascertained whether a public health stroke unit reduces the length of hospitalization, the rate of inpatient fatality, and the mortality rate 30 days after the stroke. METHODS: We compared a cohort of stroke patients managed on a general neurology/medical ward with a similar cohort of stroke patients managed in a stroke unit. The in-patient fatality rates and 30-day mortality rates were analyzed. RESULTS: 729 patients were managed in the general ward and 344 were treated at a comprehensive stroke unit. The in-patient fatality rates were 14.7% for the general ward group and 6.9% for the stroke unit group (p<0.001). The overall mortality rate 30 days after stroke was 20.9% for general ward patients and 14.2% for stroke unit patients (p=0.005). CONCLUSIONS: We observed reduced in-patient fatalities and 30-day mortality rates in patients managed in the stroke unit. There was no impact on the length of hospitalization.
Assuntos
Isquemia Encefálica/mortalidade , Mortalidade Hospitalar , Unidades Hospitalares/estatística & dados numéricos , Tempo de Internação/estatística & dados numéricos , Acidente Vascular Cerebral/mortalidade , Idoso , Idoso de 80 Anos ou mais , Brasil , Métodos Epidemiológicos , Feminino , Hospitais Públicos/estatística & dados numéricos , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Fatores de TempoRESUMO
The Holt-Oram syndrome (HOS) is an autosomal dominant condition characterized by upper limb and cardiac malformations. Mutations in the TBX5 gene cause HOS and have also been associated with isolated heart and arm defects. Interactions between the TBX5, GATA4 and NKX2.5 proteins have been reported in humans. We screened the TBX5, GATA4, and NKX2.5 genes for mutations, by direct sequencing, in 32 unrelated patients presenting classical (8) or atypical HOS (1), isolated congenital heart defects (16) or isolated upper-limb malformations (7). Pathogenic mutations in the TBX5 gene were found in four HOS patients, including two new mutations (c.374delG; c.678G > T) in typical patients, and the hotspot mutation c.835C > T in two patients, one of them with an atypical HOS phenotype involving lower-limb malformations. Two new mutations in the GATA4 gene were found in association with isolated upper-limb malformations, but their clinical significance remains to be established. A previously described possibly pathogenic mutation in the NKX2.5 gene (c.73C > 7) was detected in a patient with isolated heart malformations and also in his clinically normal father.
RESUMO
We ascertained whether a public health stroke unit reduces the length of hospitalization, the rate of inpatient fatality, and the mortality rate 30 days after the stroke. Methods We compared a cohort of stroke patients managed on a general neurology/medical ward with a similar cohort of stroke patients managed in a str oke unit. The in-patient fatality rates and 30-day mortality rates were analyzed. Results 729 patients were managed in the general ward and 344 were treated at a comprehensive stroke unit. The in-patient fatality rates were 14.7% for the general ward group and 6.9% for the stroke unit group (p<0.001). The overall mortality rate 30 days after stroke was 20.9% for general ward patients and 14.2% for stroke unit patients (p=0.005). Conclusions We observed reduced in-patient fatalities and 30-day mortality rates in patients managed in the stroke unit. There was no impact on the length of hospitalization. .
Avaliar o impacto da unidade de AVC (acidente vascular cerebral) no sistema público de saúde sobre o tempo de internação, mortalidade hospitalar e mortalidade após 30 dias do AVC agudo. Métodos Comparamos uma coorte de pacientes com AVC agudo tratados em enfermaria neurológica ou geral (EG) com uma coorte similar de pacientes com AVC tratados em uma unidade de AVC (UAVC), em um mesmo hospital público. Resultados 729 pacientes foram conduzidos na EG e 344 foram tratados em uma UAVC. A mortalidade inicial foi de 14,7% na EG e 6,9% na UAVC (p<0,001). A mortalidade geral em 30 dias após o AVC foi de 20.9% nos pacientes tratados na EG e 14,2% naqueles tratados na UAVC (p=0,005). Conclusão Observamos significante redução da mortalidade inicial e da mortalidade após 30 dias do AVC nos pacientes tratados na UAVC. Não houve impacto sobre o tempo de internação. .
Assuntos
Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Isquemia Encefálica/mortalidade , Mortalidade Hospitalar , Unidades Hospitalares/estatística & dados numéricos , Tempo de Internação/estatística & dados numéricos , Acidente Vascular Cerebral/mortalidade , Brasil , Métodos Epidemiológicos , Hospitais Públicos/estatística & dados numéricos , Fatores de Risco , Fatores de TempoRESUMO
The Holt-Oram syndrome (HOS) is an autosomal dominant condition characterized by upper limb and cardiac malformations. Mutations in the TBX5 gene cause HOS and have also been associated with isolated heart and arm defects. Interactions between the TBX5, GATA4 and NKX2.5 proteins have been reported in humans. We screened the TBX5, GATA4, and NKX2.5 genes for mutations, by direct sequencing, in 32 unrelated patients presenting classical (8) or atypical HOS (1), isolated congenital heart defects (16) or isolated upper-limb malformations (7). Pathogenic mutations in the TBX5 gene were found in four HOS patients, including two new mutations (c.374delG; c.678G > T) in typical patients, and the hotspot mutation c.835C > T in two patients, one of them with an atypical HOS phenotype involving lower-limb malformations. Two new mutations in the GATA4 gene were found in association with isolated upper-limb malformations, but their clinical significance remains to be established. A previously described possibly pathogenic mutation in the NKX2.5 gene (c.73C > 7) was detected in a patient with isolated heart malformations and also in his clinically normal father.