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1.
Acta Med Port ; 36(6): 424-427, 2023 Jun 01.
Artigo em Português | MEDLINE | ID: mdl-36753998

RESUMO

Even though it is a rare condition, hereditary spherocytosis (EH) is the main inherited cause of haemolytic anaemia and presents with a broad spectrum of symptoms. In the few reported cases of pregnancy and EH, maternal and foetal outcomes are controversial. Particularly, reports of pregnancies with EH associated with thrombosis or portal hypertension are scarce. We present a case of a woman who underwent splenectomy with EH and non-cirrhotic portal hypertension. Our patient presented polymorphisms of the methylenetetrahydrofolate reductase (MTHFR) and plasminogen activator inhibit-1 that have a controversial impact on thrombotic risk. During pregnancy, the woman showed no signs of haemodynamical or cirrhosis deterioration. Concerning the foetus, late-onset foetal growth restriction was diagnosed but did not determine preterm delivery. Five weeks post-partum after an episode of acute abdominal pain, mesenteric venous thrombosis was diagnosed. In this case report, we describe our experience in managing pregnancy, labour and post-partum of a woman with EH, highlighting potential complications of this condition.


A esferocitose hereditária (EH), embora rara, constitui a principal causa de anemia hemolítica hereditária, tendo uma apresentação clínica muito diversa. Raros casos de grávidas com EH estão publicados, tendo um impacto incerto nos desfechos maternos e fetais. Os relatos de gestações complicadas por EH e de complicações trombóticas ou hipertensão portal são particularmente escassos. Apresentamos o caso de uma grávida esplenectomizada, com EH e hipertensão portal não cirrótica. A utente apresentava polimorfismos da metiltetrahidrofolato redutase e fator inibidor do ativador do plasminogénio, mutações com impacto controverso no risco trombótico. Durante a gestação não ocorreu deterioração hemodinâmica ou hepática, diagnosticando-se restrição de crescimento fetal tardia que não condicionou término precoce da gravidez. Cinco semanas após o parto, surgiu um quadro de dor abdominal, tendo-se diagnosticado trombose de veia mesentérica. Descrevemos a nossa experiência de vigilância da gravidez, parto e puerpério de uma mulher com EH grave, com destaque para potenciais complicações associadas à EH.


Assuntos
Hipertensão Portal , Nascimento Prematuro , Esferocitose Hereditária , Gravidez , Feminino , Recém-Nascido , Humanos , Esferocitose Hereditária/complicações , Esferocitose Hereditária/diagnóstico , Hipertensão Portal/complicações , Esplenectomia
2.
J Exp Bot ; 67(5): 1545-55, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26709311

RESUMO

SHORT-ROOT (SHR) is a GRAS transcription factor first characterized for its role in the specification of the stem cell niche and radial patterning in Arabidopsis thaliana (At) roots. Three SHR-like genes have been identified in Populus trichocarpa (Pt). PtSHR1 shares high similarity with AtSHR over the entire length of the coding sequence. The two other Populus SHR-like genes, PtSHR2A and PtSHR2B, are shorter in their 5' ends when compared with AtSHR. Unlike PtSHR1, that is expressed throughout the cambial zone of greenhouse-grown Populus trees, PtSHR2Bprom:uidA expression was detected in the phellogen. Additionally, PtSHR1 and PtSHR2B expression patterns markedly differ in the shoot apex and roots of in vitro plants. Transgenic hybrid aspen expressing PtSHR2B under the 35S constitutive promoter showed overall reduced tree growth while the proportion of bark increased relative to the wood. Reverse transcription-quantitative PCR (RT-qPCR) revealed increased transcript levels of cytokinin metabolism and response-related genes in the transgenic plants consistent with an increase of total cytokinin levels. This was confirmed by cytokinin quantification by LC-MS/MS. Our results indicate that PtSHR2B appears to function in the phellogen and therefore in the regulation of phellem and periderm formation, possibly acting through modulation of cytokinin homeostasis. Furthermore, this work points to a functional diversification of SHR after the divergence of the Populus and Arabidopsis lineages. This finding may contribute to selection and breeding strategies of cork oak in which, unlike Populus, the phellogen is active throughout the entire tree lifespan, being at the basis of a highly profitable cork industry.


Assuntos
Câmbio/genética , Genes de Plantas , Proteínas de Plantas/genética , Populus/genética , Citocininas/metabolismo , Regulação da Expressão Gênica de Plantas , Hibridização Genética , Fenótipo , Proteínas de Plantas/metabolismo , Caules de Planta/anatomia & histologia , Caules de Planta/genética , Plantas Geneticamente Modificadas , Populus/crescimento & desenvolvimento , Regiões Promotoras Genéticas , Árvores/genética , Árvores/crescimento & desenvolvimento , Madeira/genética
3.
BMC Plant Biol ; 15: 158, 2015 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-26109289

RESUMO

BACKGROUND: Cork oak (Quercus suber L.) has a natural distribution across western Mediterranean regions and is a keystone forest tree species in these ecosystems. The fruiting phase is especially critical for its regeneration but the molecular mechanisms underlying the biochemical and physiological changes during cork oak acorn development are poorly understood. In this study, the transcriptome of the cork oak acorn, including the seed, was characterized in five stages of development, from early development to acorn maturation, to identify the dominant processes in each stage and reveal transcripts with important functions in gene expression regulation and response to water. RESULTS: A total of 80,357 expressed sequence tags (ESTs) were de novo assembled from RNA-Seq libraries representative of the several acorn developmental stages. Approximately 7.6 % of the total number of transcripts present in Q. suber transcriptome was identified as acorn specific. The analysis of expression profiles during development returned 2,285 differentially expressed (DE) transcripts, which were clustered into six groups. The stage of development corresponding to the mature acorn exhibited an expression profile markedly different from other stages. Approximately 22 % of the DE transcripts putatively code for transcription factors (TF) or transcriptional regulators, and were found almost equally distributed among the several expression profile clusters, highlighting their major roles in controlling the whole developmental process. On the other hand, carbohydrate metabolism, the biological pathway most represented during acorn development, was especially prevalent in mid to late stages as evidenced by enrichment analysis. We further show that genes related to response to water, water deprivation and transport were mostly represented during the early (S2) and the last stage (S8) of acorn development, when tolerance to water desiccation is possibly critical for acorn viability. CONCLUSIONS: To our knowledge this work represents the first report of acorn development transcriptomics in oaks. The obtained results provide novel insights into the developmental biology of cork oak acorns, highlighting transcripts putatively involved in the regulation of the gene expression program and in specific processes likely essential for adaptation. It is expected that this knowledge can be transferred to other oak species of great ecological value.


Assuntos
Quercus/embriologia , Quercus/genética , Sementes/embriologia , Sementes/genética , Transcriptoma/genética , Transporte Biológico/genética , Análise por Conglomerados , Perfilação da Expressão Gênica , Regulação da Expressão Gênica no Desenvolvimento , Regulação da Expressão Gênica de Plantas , Biblioteca Gênica , Anotação de Sequência Molecular , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Reação em Cadeia da Polimerase em Tempo Real , Reprodutibilidade dos Testes , Análise de Sequência de RNA , Transdução de Sinais/genética , Água
4.
BMC Genomics ; 15: 371, 2014 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-24885229

RESUMO

BACKGROUND: Cork oak (Quercus suber) is one of the rare trees with the ability to produce cork, a material widely used to make wine bottle stoppers, flooring and insulation materials, among many other uses. The molecular mechanisms of cork formation are still poorly understood, in great part due to the difficulty in studying a species with a long life-cycle and for which there is scarce molecular/genomic information. Cork oak forests are of great ecological importance and represent a major economic and social resource in Southern Europe and Northern Africa. However, global warming is threatening the cork oak forests by imposing thermal, hydric and many types of novel biotic stresses. Despite the economic and social value of the Q. suber species, few genomic resources have been developed, useful for biotechnological applications and improved forest management. RESULTS: We generated in excess of 7 million sequence reads, by pyrosequencing 21 normalized cDNA libraries derived from multiple Q. suber tissues and organs, developmental stages and physiological conditions. We deployed a stringent sequence processing and assembly pipeline that resulted in the identification of ~159,000 unigenes. These were annotated according to their similarity to known plant genes, to known Interpro domains, GO classes and E.C. numbers. The phylogenetic extent of this ESTs set was investigated, and we found that cork oak revealed a significant new gene space that is not covered by other model species or EST sequencing projects. The raw data, as well as the full annotated assembly, are now available to the community in a dedicated web portal at http://www.corkoakdb.org. CONCLUSIONS: This genomic resource represents the first trancriptome study in a cork producing species. It can be explored to develop new tools and approaches to understand stress responses and developmental processes in forest trees, as well as the molecular cascades underlying cork differentiation and disease response.


Assuntos
Etiquetas de Sequências Expressas , Quercus/genética , Transcriptoma , DNA de Plantas/análise , Biblioteca Gênica , Filogenia , Quercus/crescimento & desenvolvimento , Análise de Sequência de DNA
5.
PLoS One ; 7(4): e35113, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22529976

RESUMO

The use of reverse transcription quantitative PCR technology to assess gene expression levels requires an accurate normalization of data in order to avoid misinterpretation of experimental results and erroneous analyses. Despite being the focus of several transcriptomics projects, oaks, and particularly cork oak (Quercus suber), have not been investigated regarding the identification of reference genes suitable for the normalization of real-time quantitative PCR data. In this study, ten candidate reference genes (Act, CACs, EF-1α, GAPDH, His3, PsaH, Sand, PP2A, ß-Tub and Ubq) were evaluated to determine the most stable internal reference for quantitative PCR normalization in cork oak. The transcript abundance of these genes was analysed in several tissues of cork oak, including leaves, reproduction cork, and periderm from branches at different developmental stages (1-, 2-, and 3-year old) or collected in different dates (active growth period versus dormancy). The three statistical methods (geNorm, NormFinder, and CV method) used in the evaluation of the most suitable combination of reference genes identified Act and CACs as the most stable candidates when all the samples were analysed together, while ß-Tub and PsaH showed the lowest expression stability. However, when different tissues, developmental stages, and collection dates were analysed separately, the reference genes exhibited some variation in their expression levels. In this study, and for the first time, we have identified and validated reference genes in cork oak that can be used for quantification of target gene expression in different tissues and experimental conditions and will be useful as a starting point for gene expression studies in other oaks.


Assuntos
Perfilação da Expressão Gênica , Quercus/genética , Reação em Cadeia da Polimerase em Tempo Real/normas , Regulação da Expressão Gênica de Plantas , RNA de Plantas/isolamento & purificação , Padrões de Referência , Reprodutibilidade dos Testes
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