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1.
Sci Rep ; 10(1): 21798, 2020 12 11.
Artigo em Inglês | MEDLINE | ID: mdl-33311534

RESUMO

Distribution patterns of fragile gelatinous fauna in the open ocean remain scarcely documented. Using epi-and mesopelagic video transects in the eastern tropical North Atlantic, which features a mild but intensifying midwater oxygen minimum zone (OMZ), we established one of the first regional observations of diversity and abundance of large gelatinous zooplankton. We quantified the day and night vertical distribution of 46 taxa in relation to environmental conditions. While distribution may be driven by multiple factors, abundance peaks of individual taxa were observed in the OMZ core, both above and below the OMZ, only above, or only below the OMZ whereas some taxa did not have an obvious distribution pattern. In the eastern eropical North Atlantic, OMZ expansion in the course of global climate change may detrimentally impact taxa that avoid low oxygen concentrations (Beroe, doliolids), but favour taxa that occur in the OMZ (Lilyopsis, phaeodarians, Cydippida, Colobonema, Haliscera conica and Halitrephes) as their habitat volume might increase. While future efforts need to focus on physiology and taxonomy of pelagic fauna in the study region, our study presents biodiversity and distribution data for the regional epi- and mesopelagic zones of Cape Verde providing a regional baseline to monitor how climate change may impact the largest habitat on the planet, the deep pelagic realm.


Assuntos
Biodiversidade , Zooplâncton , Animais , Oceano Atlântico , Cabo Verde , Zooplâncton/classificação , Zooplâncton/fisiologia
2.
Genes Immun ; 12(8): 653-62, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21716316

RESUMO

Colorectal cancer (CRC) incidence increases with age, and early onset of the disease is an indication of genetic predisposition, estimated to cause up to 30% of all cases. To identify genes associated with early-onset CRC, we investigated gene expression levels within a series of young patients with CRCs who are not known to carry any hereditary syndromes (n=24; mean 43 years at diagnosis), and compared this with a series of CRCs from patients diagnosed at an older age (n=17; mean 79 years). Two individual genes were found to be differentially expressed between the two groups, with statistical significance; CLC was higher and IFNAR1 was less expressed in early-onset CRCs. Furthermore, genes located at chromosome band 19q13 were found to be enriched significantly among the genes with higher expression in the early-onset samples, including CLC. An elevated immune content within the early-onset group was observed from the differentially expressed genes. By application of outlier statistics, H3F3A was identified as a top candidate gene for a subset of the early-onset CRCs. In conclusion, CLC and IFNAR1 were identified to be overall differentially expressed between early- and late-onset CRC, and are important in the development of early-onset CRC.


Assuntos
Neoplasias Colorretais/genética , Neoplasias Colorretais/imunologia , Regulação Neoplásica da Expressão Gênica , Glicoproteínas/genética , Lisofosfolipase/genética , Receptor de Interferon alfa e beta/genética , Adulto , Idade de Início , Idoso , Idoso de 80 Anos ou mais , Análise por Conglomerados , Neoplasias Colorretais/epidemiologia , Perfilação da Expressão Gênica , Glicoproteínas/metabolismo , Humanos , Lisofosfolipase/metabolismo , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Receptor de Interferon alfa e beta/metabolismo
3.
Am J Med Genet ; 63(1): 223-30, 1996 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-8723114

RESUMO

Conversion of testosterone (T) to dihydrotestosterone (DHT) in genital tissue is catalysed by the enzyme 5 alpha-reductase 2, which is encoded by the SRD5A2 gene. The potent androgen DHT is required for full masculinization of the external genitalia. Mutations of the SRD5A2 gene inhibit enzyme activity, diminish DHT formation, and hence cause masculinization defects of varying degree. The classical syndrome, formerly described as pseudovaginal perineoscrotal hypospadias, is characterized by a predominantly female phenotype at birth and significant virilization without gynecomastia at puberty. We investigated nine patients with steroid 5 alpha-reductase 2 deficiency (SRD). Phenotypes, which were classified according to the severity of the masculinization defect, varied between completely female (SRD type 5), predominantly female (SRD type 4), ambiguous (SRD type 3), predominantly male with micropenis and hypospadias (SRD type 2), and completely male without overt signs of undermasculinization (SRD type 1). T/DHT-ratios were highly increased ( > 50) in the classical syndrome (SRD type 5), but variable in the less severe affected patients (SRD types 1-4) (14-35). Mutations in the SRD5A2 gene had been characterized using PCR-SSCP analysis and direct DNA sequencing. A small deletion was encountered in two patients, while all other patients had single base mutations which result in amino acid substitutions. We conclude that phenotypes may vary widely in patients with SRD5A2 gene mutations spanning the whole range from completely female to normal male without distinctive clinical signs of the disease. Hence, steroid 5 alpha-reductase deficiency should be considered not only in sex reversed patients with female or ambiguous phenotypes, but also in those with mild symptoms of undermasculinization as encountered in patients with hypospadias and/or micropenis. A classification based on the severity of the masculinization defect may be used for correlation of phenotypes with enzyme activities and genotypes, and for comparisons of phenotypes between different patients as the basis for clinical decisions to be made in patients with pseudohermaphroditism due to steroid 5 alpha-reductase 2 deficiency.


Assuntos
3-Oxo-5-alfa-Esteroide 4-Desidrogenase/deficiência , 3-Oxo-5-alfa-Esteroide 4-Desidrogenase/genética , Transtornos do Desenvolvimento Sexual/classificação , Transtornos do Desenvolvimento Sexual/genética , Mutação Puntual , Deleção de Sequência , Adolescente , Criança , Pré-Escolar , Diagnóstico Diferencial , Di-Hidrotestosterona/sangue , Feminino , Humanos , Hipospadia/genética , Lactente , Masculino , Pênis/anormalidades , Fenótipo , Testosterona/sangue
4.
Prenat Diagn ; 12(11): 945-50, 1992 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-1494547

RESUMO

The case of monosomy 18/ring chromosome 18 mosaicism which was detected prenatally by amniocentesis is presented. The pregnancy was terminated in week 18. Autopsy showed complex malformation of the fetus consisting of cebocephaly, hypotelorism, microphthalmia, severe defects of brain development, and arrest of placental maturation.


Assuntos
Amniocentese , Cromossomos Humanos Par 18 , Monossomia , Mosaicismo , Cromossomos em Anel , Adulto , Encéfalo/anormalidades , Vilosidades Coriônicas/ultraestrutura , Amostra da Vilosidade Coriônica , Feminino , Humanos , Gravidez
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