Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 14 de 14
Filtrar
1.
Astrobiology ; 19(4): 553-578, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30653331

RESUMO

The Dallol volcano and its associated hydrothermal field are located in a remote area of the northern Danakil Depression in Ethiopia, a region only recently appraised after decades of inaccessibility due to severe political instability and the absence of infrastructure. The region is notable for hosting environments at the very edge of natural physical-chemical extremities. It is surrounded by a wide, hyperarid salt plain and is one of the hottest (average annual temperatureDallol: 36-38°C) and most acidic natural systems (pHDallol ≈0) on Earth. Spectacular geomorphologies and mineral deposits produced by supersaturated hydrothermal waters and brines are the result of complex interactions between active and inactive hydrothermal alteration of the bedrock, sulfuric hot springs and pools, fumaroles and geysers, and recrystallization processes driven by hydrothermal waters, degassing, and rapid evaporation. The study of planetary field analog environments plays a crucial role in characterizing the physical and chemical boundaries within which life can exist on Earth and other planets. It is essential for the definition and assessment of the conditions of habitability on other planets, including the possibility for biosignature preservation and in situ testing of technologies for life detection. The Dallol area represents an excellent Mars analog environment given that the active volcanic environment, the associated diffuse hydrothermalism and hydrothermal alteration, and the vast acidic sulfate deposits are reminiscent of past hydrothermal activity on Mars. The work presented in this paper is an overview of the Dallol volcanic area and its hydrothermal field that integrates previous literature with observations and results obtained from field surveys and monitoring coupled with sample characterization. In so doing, we highlight its exceptional potential as a planetary field analog as well as a site for future astrobiological and exploration programs.


Assuntos
Planeta Terra , Meio Ambiente Extraterreno , Ácidos/química , Clima , Etiópia , Exobiologia , Gases/análise , Geografia , Fontes Termais/microbiologia , Marte , Minerais/química , Sais/química , Comunicações Via Satélite , Temperatura
3.
Int J STD AIDS ; 21(7): 472-6, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20852196

RESUMO

HIV-positive women with pelvic inflammatory disease have been reported to have an increased prevalence of tuboovarian masses (TOMs). The aim of this study was to assess the prevalence of asymptomatic ultrasonographic TOMs in women with HIV and to identify associated factors in order to formulate a selective ultrasonographic screening strategy. Two-hundred and four HIV outpatients underwent transvaginal ultrasonography. Eight (3.9%) had a diagnosis of TOM (5 were asymptomatic). Two profiles of patients at risk for TOM were identified who could be considered for selective screening strategies: the 'long-term infected' (age>35 years, diagnosis of HIV infection more than 5 years ago, HIV clinical category C, CD4 counts below 200/mm(3), >5 lifetime partners and on antiretroviral therapy) and the 'recently diagnosed with HIV' (African ethnicity, age 25-35, HIV diagnosis in the previous year, >5 lifetime partners, HIV clinical category C and not on antiretroviral therapy).


Assuntos
Neoplasias das Tubas Uterinas/epidemiologia , Neoplasias das Tubas Uterinas/patologia , Infecções por HIV/complicações , Neoplasias Ovarianas/epidemiologia , Neoplasias Ovarianas/patologia , Adolescente , Adulto , Criança , Detecção Precoce de Câncer/métodos , Feminino , Humanos , Pessoa de Meia-Idade , Prevalência , Ultrassonografia/métodos , Adulto Jovem
4.
Minerva Ginecol ; 61(2): 109-12, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19255558

RESUMO

AIM: The aim of this study was to evaluate the clinical significance and the management of fetal borderline lateral cerebral ventriculomegaly. METHODS: Fetuses with a sonographic diagnosis of lateral cerebral ventriculomegaly isolated or associated to other fetal malformations were followed monthly and a review of the English-language literature was made. RESULTS: Of 86 fetuses analyzed, 30 suffered from hydrocephaly (monolateral, bilateral), 56 showed also several other malformations . Chromosomal aberrations is possible also in case of isolated hydrocephaly. Neurological sequelae, mostly a mild to moderate delay in cognitive and/or motor development, is present in 10% of the cases. CONCLUSIONS: In most cases, isolated borderline lateral cerebral ventriculomegaly has no consequence. However, the risk of cerebral maldevelopment, delayed neurological development and, possibly, chromosomal aberrations is increased. The optimum management of these cases remains uncertain.


Assuntos
Anormalidades Múltiplas/diagnóstico por imagem , Hidrocefalia/diagnóstico por imagem , Ventrículos Laterais/anormalidades , Ultrassonografia Pré-Natal , Aborto Legal , Adulto , Ventrículos Cerebrais/anormalidades , Feminino , Humanos , Valor Preditivo dos Testes , Gravidez , Resultado da Gravidez , Segundo Trimestre da Gravidez , Terceiro Trimestre da Gravidez , Diagnóstico Pré-Natal , Estudos Retrospectivos , Medição de Risco , Índice de Gravidade de Doença
6.
Prenat Diagn ; 26(1): 67-70, 2006 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-16378326

RESUMO

The association between monozygotic twins and posterior urethral valves (PUV) in postnatal life has been thoroughly described. In the fetus, the prenatal recognition of PUV is feasible. However, it has been repeatedly reported in singletons but never in monochorionic twins. We describe two cases of early prenatal diagnosis of concordant PUVs in monochorionic twins. In one of the sets, the expression of the disease was different for each twin.


Assuntos
Hidronefrose/diagnóstico , Diagnóstico Pré-Natal , Gêmeos Monozigóticos , Uretra/anormalidades , Adulto , Diagnóstico Diferencial , Feminino , Humanos , Hidronefrose/diagnóstico por imagem , Hidronefrose/embriologia , Hidronefrose/patologia , Masculino , Gravidez , Segundo Trimestre da Gravidez , Ultrassonografia , Uretra/diagnóstico por imagem , Uretra/patologia
7.
Minerva Ginecol ; 57(6): 649-54, 2005 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-16306870

RESUMO

Placental chorioangioma is the most common benign tumor of placenta. The relationship of vascularized chorioangiomas to adverse pregnancy outcome is well recognized. We report 3 cases of placental chorioangioma. Hypervascularization of the lesions in all patients and the immune hydrops with adverse fetal outcome in 2 cases are the complications of our mini-series. Ultrasonography and Doppler ultrasonography findings were useful in establishing the prenatal diagnosis and the prognosis.


Assuntos
Hemangioma/diagnóstico por imagem , Doenças Placentárias/diagnóstico por imagem , Ultrassonografia Pré-Natal , Adulto , Feminino , Humanos , Gravidez
8.
Prenat Diagn ; 25(1): 23-7, 2005 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-15662698

RESUMO

Spilt notochord syndrome is an extremely rare form of spinal dysraphism characterized by a complete cleft of the spine and a persistent communication between endoderm and ectoderm. A variant of split notochord syndrome was diagnosed in a 25-week-old fetus showing a prolapsed congenital colostomy and a spinal cystic lesion. The final diagnosis included protruding colon segment, imperforate anus with a rectourethral fistula and lipomyelomeningocele. The ultrasound features of the condition and the post-natal management are discussed. The neonate was successfully treated with a posterior sagittal anorectoplasty, while the lipomyelomeningocele was resected at a later stage.


Assuntos
Anormalidades Múltiplas/cirurgia , Notocorda/anormalidades , Disrafismo Espinal , Ultrassonografia Pré-Natal , Adulto , Colo/anormalidades , Feminino , Humanos , Recém-Nascido , Fístula Intestinal/congênito , Fístula Intestinal/cirurgia , Masculino , Meningomielocele/patologia , Meningomielocele/cirurgia , Gravidez , Disrafismo Espinal/complicações , Disrafismo Espinal/patologia , Disrafismo Espinal/cirurgia , Síndrome , Resultado do Tratamento
9.
Ultrasound Obstet Gynecol ; 24(2): 199-201, 2004 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-15287060

RESUMO

Oculoauriculovertebral spectrum, or Goldenhar syndrome, is characterized by varying degrees of prevalently unilateral underdevelopment of craniofacial structures (orbit, ear, mandible) and spinal anomalies. We report the prenatal ultrasonographic diagnosis made at 24 weeks' gestation in a family with a negative history. The prenatal diagnosis was suspected due to the presence of marked hemifacial microsomia and moderate ipsilateral cerebellar hemisphere hypoplasia in the absence of facial clefting.


Assuntos
Assimetria Facial/diagnóstico por imagem , Doenças Fetais/diagnóstico por imagem , Síndrome de Goldenhar/diagnóstico por imagem , Ultrassonografia Pré-Natal/métodos , Adulto , Cerebelo/anormalidades , Cerebelo/diagnóstico por imagem , Feminino , Humanos , Gravidez
10.
J Endocrinol Invest ; 27(4): 357-60, 2004 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-15233556

RESUMO

Multiple endocrine neoplasia 2A (MEN 2A) is an inherited dominant syndrome characterised by medullary thyroid carcinoma, adrenal pheochromocytoma and hyperparathyroidism due to specific RET proto-oncogene mutations. Fertile MEN 2A women are at risk of complicated pregnancy because of unrecognised pheochromocytoma and transmission of RET mutation to the progeny. This condition may cause psychological distress in affected pregnant patients and their families. Here we describe the genetic prenatal testing, the pregnancy management and obstetric outcome in a MEN 2A patient with a right side adrenal hyperplasia and elevated calcitonin levels, a condition suspicious for possible recurrence of pheochromocytoma. We confirm that maternal or fetal complications are rare when MEN 2A diagnosis is made before pregnancy and an accurate monitoring is instituted. Furthermore, our results indicate that prenatal testing for RET mutations is highly recommended in making decisions and assuring parents on the lifelong risk of tumors. This will avoid the psychological distress that can further complicate the pregnancy of affected women.


Assuntos
Neoplasia Endócrina Múltipla Tipo 2a/genética , Proteínas Oncogênicas/genética , Complicações na Gravidez , Diagnóstico Pré-Natal , Receptores Proteína Tirosina Quinases/genética , Hiperplasia Suprarrenal Congênita/complicações , Hiperplasia Suprarrenal Congênita/genética , Adulto , Calcitonina/sangue , Feminino , Humanos , Cariotipagem , Neoplasia Endócrina Múltipla Tipo 2a/diagnóstico , Mutação , Reação em Cadeia da Polimerase , Gravidez , Proto-Oncogene Mas , Proteínas Proto-Oncogênicas c-ret
12.
Ultrasound Obstet Gynecol ; 17(2): 163-5, 2001 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11251928

RESUMO

The Pena-Shokeir phenotype represents an autosomal recessive syndrome characterized by neurogenic arthrogryposis, facial anomalies and pulmonary hypoplasia. Prenatal diagnosis of this disease has been reported prospectively and in cases with positive family history. We describe here a patient who has had three consecutive pregnancies affected by the Pena-Shokeir syndrome. In these pregnancies, the onset of the arthrogryposis varied between the 12th and the 18th week of gestation. Therefore, the possibility of a variable chronological development of the main diagnostic feature of the syndrome, arthrogryposis, has to be taken into proper consideration while counseling families with a positive history for the Pena-Shokeir phenotype.


Assuntos
Artrogripose/diagnóstico por imagem , Doenças Fetais/diagnóstico por imagem , Ultrassonografia Pré-Natal , Adulto , Feminino , Humanos , Pulmão/embriologia , Fenótipo , Gravidez , Recidiva , Síndrome
14.
Ultrasound Obstet Gynecol ; 15(2): 104-8, 2000 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10775990

RESUMO

OBJECTIVE: To assess the relationship between congenital heart disease (CHD) and Down syndrome (DS) in utero. DESIGN: Retrospective case series. SUBJECTS: Fifty-two fetuses with a cytogenetic diagnosis of DS managed at our Fetal Cardiology Unit in the study period. In particular, two populations of fetuses with DS were studied: a group of 41 DS fetuses referred to our unit for fetal echocardiography due to the chromosomal anomaly and a second group of 274 fetuses referred because of suspected CHD, 11 of which were found to have DS. METHODS: All fetuses were submitted to detailed ultrasound evaluation of fetal anatomy. Associated extracardiac anomalies, and presence and type of CHD, were recorded for all fetuses. Karyotyping was obtained by means of cordocentesis or amniocentesis. Necropsy or neonatal echocardiograms were sought for confirmation of the prenatal diagnosis. RESULTS: In the group of 41 fetuses with known DS, the incidence of CHD was 56% ([atrioventricular septal defect (AVSD) 44%, ventricular septal defect (VSD) 48%], the remainder having other heart defects). Conversely, considering the incidence of DS in fetuses with CHD, 43% of all AVSDs (53% of AVSD with normal visceral situs) were associated with DS, whereas none of the 39 cases of VSD was associated with trisomy 21. Ventricular septal defects were diagnosed only in fetuses referred to our center with a known diagnosis of aneuploidy. CONCLUSIONS: We have confined that more than half of the fetuses with DS bear a CHD, which is an AVSD in 44% of cases. Conversely, 43% of fetuses with an AVSD have trisomy 21. For VSDS, the situation is controversial, due to the relatively low detection level of this heart defect at the routine mid-trimester obstetric scan.


Assuntos
Anormalidades Múltiplas/diagnóstico , Síndrome de Down/diagnóstico , Doenças Fetais/diagnóstico , Cardiopatias Congênitas/diagnóstico , Anormalidades Múltiplas/genética , Adulto , Amniocentese , Aneuploidia , Síndrome de Down/genética , Ecocardiografia , Feminino , Doenças Fetais/genética , Idade Gestacional , Cardiopatias Congênitas/genética , Humanos , Incidência , Cariotipagem , Programas de Rastreamento , Gravidez , Segundo Trimestre da Gravidez , Encaminhamento e Consulta , Estudos Retrospectivos , Ultrassonografia Pré-Natal
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...