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1.
Clin Nucl Med ; 49(2): e77-e79, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38048523

RESUMO

ABSTRACT: Despite extensive research into COVID-19 since its emergence in late 2019, there is still much not fully understood about its long-term effects. When infected with SARS-CoV-2, cancer patients have been reported to be at higher risk for unfavorable outcomes. Nevertheless, evidence suggests that viruses may exhibit an antitumor effect in some cases, which has recently been anecdotally reported with SARS-CoV-2. We present the case of a patient with a recent high-grade non-Hodgkin lymphoma diagnosis and without any cancer-specific therapy, in whom a complete metabolic response on 2-[ 18 F]FDG PET/CT was observed after COVID-19.


Assuntos
COVID-19 , Linfoma não Hodgkin , Neoplasias , Humanos , COVID-19/complicações , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Remissão Espontânea , Fluordesoxiglucose F18 , SARS-CoV-2 , Linfoma não Hodgkin/complicações , Linfoma não Hodgkin/diagnóstico por imagem
2.
Acta Med Port ; 36(7-8): 517-526, 2023 Jul 03.
Artigo em Português | MEDLINE | ID: mdl-37429590

RESUMO

The treatment of multiple myeloma has profoundly changed with the introduction of several innovative therapies. The optimization of therapeutic sequencing through the combined use of the various drugs developed in recent years and the attention given to the characteristics of patients have allowed the reduction of toxicities and increased survival and quality of life of patients with multiple myeloma. These treatment recommendations from the Portuguese Multiple Myeloma Group offer guidance for first-line treatment and progression/relapse situations. These recommendations are given highlighting the data that justify each choice and referring to the respective levels of evidence that support these options. Whenever possible, the respective national regulatory framework is presented. These recommendations constitute an advance towards the best treatment of multiple myeloma in Portugal.


O tratamento do mieloma múltiplo tem sido amplamente alterado com introdução de várias terapêuticas inovadoras. A otimização da sequenciação terapêutica através do uso combinado dos vários fármacos desenvolvidos nos últimos anos e a atenção dada às características dos doentes têm permitido diminuir toxicidades e aumentar a sobrevivência dos doentes, bem como aumentar a sua qualidade de vida. As presentes recomendações terapêuticas do Grupo Português do Mieloma Múltiplo oferecem orientações para o tratamento de primeira linha e progressão/recaída. As recomendações são fundamentadas evidenciando os dados que justificam cada escolha e referindo os respetivos níveis de evidência que suportam essas opções. Sempre que possível é apresentado o respetivo enquadramento regulamentar nacional. Estas recomendações constituem um avanço para o melhor tratamento do mieloma múltiplo em Portugal.


Assuntos
Mieloma Múltiplo , Humanos , Mieloma Múltiplo/tratamento farmacológico , Portugal , Qualidade de Vida , Recidiva Local de Neoplasia/tratamento farmacológico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico
3.
Philos Trans R Soc Lond B Biol Sci ; 377(1850): 20210217, 2022 05 09.
Artigo em Inglês | MEDLINE | ID: mdl-35306887

RESUMO

The number of dioecious species for which the genetic basis of sex determination has been resolved is rapidly increasing. Nevertheless, the molecular mechanisms downstream of the sex determinants remain largely elusive. Here, by RNA-sequencing early-flowering isogenic aspen (Populus tremula) lines differing exclusively for the sex switch gene ARR17, we show that a narrowly defined genetic network controls differential development of female and male flowers. Although ARR17 encodes a type-A response regulator supposedly involved in cytokinin (CK) hormone signalling, clustered regularly interspaced short palindromic repeats (CRISPR)-Cas9-mediated arr17 knockout only affected the expression of a strikingly small number of genes, indicating a specific role in the regulation of floral development rather than a generic function in hormone signalling. Notably, the UNUSUAL FLORAL ORGANS (UFO) gene, encoding an F-box protein acting as a transcriptional cofactor with LEAFY (LFY) to activate B-class MADS-box gene expression, and the B-class gene PISTILLATA (PI), necessary for male floral organ development, were strongly de-repressed in the arr17 CRISPR mutants. Our data highlight a CK-independent role of the poplar response regulator ARR17 and further emphasize the minimal differences between female and male individuals. This article is part of the theme issue 'Sex determination and sex chromosome evolution in land plants'.


Assuntos
Populus , Flores/genética , Expressão Gênica , Regulação da Expressão Gênica de Plantas , Redes Reguladoras de Genes , Genes de Plantas , Hormônios/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Populus/genética
4.
Plants (Basel) ; 9(10)2020 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-32992588

RESUMO

European beech, Fagus sylvatica L., is one of the most important and widespread deciduous tree species in Central Europe and is widely managed for its hard wood. The complete DNA sequence of the mitochondrial genome of Fagus sylvatica L. was assembled and annotated based on Illumina MiSeq reads and validated using long reads from nanopore MinION sequencing. The genome assembled into a single DNA sequence of 504,715 bp in length containing 58 genes with predicted function, including 35 protein-coding, 20 tRNA and three rRNA genes. Additionally, 23 putative protein-coding genes were predicted supported by RNA-Seq data. Aiming at the development of taxon-specific mitochondrial genetic markers, the tool SNPtax was developed and applied to select genic SNPs potentially specific for different taxa within the Fagales. Further validation of a small SNP set resulted in the development of four CAPS markers specific for Fagus, Fagaceae, or Fagales, respectively, when considering over 100 individuals from a total of 69 species of deciduous trees and conifers from up to 15 families included in the marker validation. The CAPS marker set is suitable to identify the genus Fagus in DNA samples from tree tissues or wood products, including wood composite products.

5.
Nat Plants ; 6(6): 630-637, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32483326

RESUMO

Although hundreds of plant lineages have independently evolved dioecy (that is, separation of the sexes), the underlying genetic basis remains largely elusive1. Here we show that diverse poplar species carry partial duplicates of the ARABIDOPSIS RESPONSE REGULATOR 17 (ARR17) orthologue in the male-specific region of the Y chromosome. These duplicates give rise to small RNAs apparently causing male-specific DNA methylation and silencing of the ARR17 gene. CRISPR-Cas9-induced mutations demonstrate that ARR17 functions as a sex switch, triggering female development when on and male development when off. Despite repeated turnover events, including a transition from the XY system to a ZW system, the sex-specific regulation of ARR17 is conserved across the poplar genus and probably beyond. Our data reveal how a single-gene-based mechanism of dioecy can enable highly dynamic sex-linked regions and contribute to maintaining recombination and integrity of sex chromosomes.


Assuntos
Genes de Plantas , Peptídeos e Proteínas de Sinalização Intracelular/genética , Proteínas de Plantas/genética , Populus/genética , Cromossomos de Plantas , Processos de Determinação Sexual
6.
Transgenic Res ; 29(3): 321-337, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32356192

RESUMO

Next-generation sequencing (NGS) approaches are attractive alternatives to the PCR-based characterisation of genetically modified plants for safety assessment and labelling since NGS is highly sensitive to the detection of T-DNA inserts as well as vector backbone sequences in transgenic plants. In this study, two independent transgenic male Populus tremula lines, T193-2 and T195-1, both carrying the FLOWERING LOCUS T gene from Arabidopsis thaliana under control of a heat-inducible promoter (pHSP::AtFT) and the non-transgenic control clone W52, were further characterised by NGS and third-generation sequencing. The results support previous findings that the T-DNA was hemizygously inserted in one genomic locus of each line. However, the T-DNA insertions consist of conglomerations of one or two T-DNA copies together with a small T-DNA fragment without AtFT parts. Based on NGS data, no additional T-DNA splinters or vector backbone sequences could be identified in the genome of the two transgenic lines. Seedlings derived from crosses between the pHSP::AtFT transgenic male parents and female wild type plants are therefore expected to be T-DNA splinter or vector backbone free. Thus, PCR analyses amplifying a partial T-DNA fragment with AtFT-specific primers are sufficient to determine whether the seedlings are transgenic or not. An analysis of 72 second generation-seedlings clearly showed that about 50% of them still reveal the presence of the T-DNA, confirming data already published. To prove if unanticipated genomic changes were induced by T-DNA integration, extended future studies using long-range sequencing technologies are required once a suitable chromosome-level P. tremula reference genome sequence is available.


Assuntos
Arabidopsis/genética , DNA Bacteriano/genética , Flores/genética , Regulação da Expressão Gênica de Plantas , Plantas Geneticamente Modificadas/genética , Populus/genética , Transgenes , Flores/crescimento & desenvolvimento , Plantas Geneticamente Modificadas/crescimento & desenvolvimento , Populus/crescimento & desenvolvimento
7.
Front Plant Sci ; 11: 580488, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33519840

RESUMO

The diversity of inflorescences among flowering plants is captivating. Such charm is not only due to the variety of sizes, shapes, colors, and flowers displayed, but also to the range of reproductive systems. For instance, hermaphrodites occur abundantly throughout the plant kingdom with both stamens and carpels within the same flower. Nevertheless, 10% of flowering plants have separate unisexual flowers, either in different locations of the same individual (monoecy) or on different individuals (dioecy). Despite their rarity, dioecious plants provide an excellent opportunity to investigate the mechanisms involved in sex expression and the evolution of sex-determining regions (SDRs) and sex chromosomes. The SDRs and the evolution of dioecy have been studied in many species ranging from Ginkgo to important fruit crops. Some of these studies, for example in asparagus or kiwifruit, identified two sex-determining genes within the non-recombining SDR and may thus be consistent with the classical model for the evolution of dioecy from hermaphroditism via gynodioecy, that predicts two successive mutations, the first one affecting male and the second one female function, becoming linked in a region of suppressed recombination. On the other hand, aided by genome sequencing and gene editing, single factor sex determination has emerged in other species, such as persimmon or poplar. Despite the diversity of sex-determining mechanisms, a tentative comparative analysis of the known sex-determining genes and candidates in different species suggests that similar genes and pathways may be employed repeatedly for the evolution of dioecy. The cytokinin signaling pathway appears important for sex determination in several species regardless of the underlying genetic system. Additionally, tapetum-related genes often seem to act as male-promoting factors when sex is determined via two genes. We present a unified model that synthesizes the genetic networks of sex determination in monoecious and dioecious plants and will support the generation of hypothesis regarding candidate sex determinants in future studies.

8.
Acta Med Port ; 32(7-8): 550-557, 2019 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-31445538

RESUMO

Until recently, the main goal of chronic myeloid leukemia therapy was disease control with the best overall survival, which required lifelong treatment. However, currently, the treatment-free remission concept is becoming an important goal in clinical practice, and several tyrosine kinase inhibitors discontinuation studies have shown that round 50% of patients with a durable deep molecular response beyond major molecular response successfully interrupt tyrosine kinase inhibitors for at least three years without loss of molecular response. However, and regardless of the existing evidence, the exact conditions for attempting treatment-free remission remain poorly defined. Different authors tried to guide the clinical decision regarding this topic but there are some points that differ, namely with respect to the recommended duration of tyrosine kinase inhibitors therapy and the appropriate molecular response prior to treatment-free remission. The goal of this article is to propose an algorithm to guide clinical practice in Portugal concerning chronic phase-chronic myeloid leukemia patients who wish to attempt treatment-free remission, since there are no national guidelines.


Até recentemente, o objectivo principal do tratamento da leucemia mielóide crónica era o controlo da doença com o maior tempo possível de sobrevivência, o que requeria tratamento durante toda a vida. No entanto, e actualmente, o conceito de remissão livre de tratamento está a tornar-se um objectivo importante na prática clínica, e vários estudos de descontinuação de inibidores de tirosina cinase mostraram que cerca de 50% dos doentes com uma resposta molecular profunda duradoura, para além da resposta molecular major, interrompem tratamento com inibidores de tirosina cinase com sucesso durante pelo menos três anos sem perda da resposta molecular. No entanto, e apesar da evidência existente, as condições concretas e exactas para tentar remissão livre de tratamento são ainda pouco conhecidas. Diferentes autores tentaram guiar a decisão clínica sobre este tópico mas alguns pontos permanecem não consensuais, nomeadamente no que respeita à duração recomendada de tratamento com inibidores de tirosina cinase e à resposta molecular apropriada antes de tentar remissão livre de tratamento. O objectivo desta publicação é propor um algoritmo que permita guiar a prática clínica em Portugal relativa a doentes com leucemia mielóide crónica ou em fase crónica que pretendam tentar remissão livre de tratamento, dada a ausência de recomendações nacionais.


Assuntos
Leucemia Mielogênica Crônica BCR-ABL Positiva , Inibidores de Proteínas Quinases , Suspensão de Tratamento/normas , Ensaios Clínicos como Assunto , Proteínas de Fusão bcr-abl/metabolismo , Humanos , Leucemia Mielogênica Crônica BCR-ABL Positiva/tratamento farmacológico , Leucemia Mielogênica Crônica BCR-ABL Positiva/metabolismo , Leucemia Mielogênica Crônica BCR-ABL Positiva/mortalidade , Portugal , Inibidores de Proteínas Quinases/uso terapêutico , Indução de Remissão
9.
Leuk Res ; 36(8): 1071-3, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22607959

RESUMO

Chronic myelomonocytic leukemia (CMML) is a clinically heterogeneous disease, with no standard treatment. We present the outcome of ten patients diagnosed with CMML and treated with AZA in our institutions between 2005 and 2010. All patients were transfusion dependent at the time of initiation of therapy. The overall response rate was 60%. Responses were obtained in 2/3 of the patients with proliferative CMML. The median survival from start of therapy was 20 months. AZA treatment was well-tolerated and associated with a significant response rate in all forms of the disease.


Assuntos
Azacitidina/uso terapêutico , Leucemia Mielomonocítica Crônica/tratamento farmacológico , Adulto , Idoso , Antimetabólitos Antineoplásicos/uso terapêutico , Feminino , Humanos , Leucemia Mielomonocítica Crônica/diagnóstico , Masculino , Pessoa de Meia-Idade , Prognóstico , Resultado do Tratamento
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