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1.
Genes Dev ; 33(7-8): 466-476, 2019 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-30819818

RESUMO

The endosperm is an ephemeral tissue that nourishes the developing embryo, similar to the placenta in mammals. In most angiosperms, endosperm development starts as a syncytium, in which nuclear divisions are not followed by cytokinesis. The timing of endosperm cellularization largely varies between species, and the event triggering this transition remains unknown. Here we show that increased auxin biosynthesis in the endosperm prevents its cellularization, leading to seed arrest. Auxin-overproducing seeds phenocopy paternal-excess triploid seeds derived from hybridizations of diploid maternal plants with tetraploid fathers. Concurrently, auxin-related genes are strongly overexpressed in triploid seeds, correlating with increased auxin activity. Reducing auxin biosynthesis and signaling reestablishes endosperm cellularization in triploid seeds and restores their viability, highlighting a causal role of increased auxin in preventing endosperm cellularization. We propose that auxin determines the time of endosperm cellularization, and thereby uncovered a central role of auxin in establishing hybridization barriers in plants.


Assuntos
Arabidopsis/crescimento & desenvolvimento , Arabidopsis/genética , Endosperma , Regulação da Expressão Gênica de Plantas/genética , Ácidos Indolacéticos/metabolismo , Proteínas de Arabidopsis/genética , Regulação para Baixo , Endosperma/citologia , Endosperma/genética , Endosperma/crescimento & desenvolvimento , Mutação , Poliploidia , Sementes/genética , Sementes/crescimento & desenvolvimento , Transdução de Sinais/genética
2.
Genes Dev ; 32(7-8): 479-490, 2018 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-29692356

RESUMO

The evolution of seeds defines a remarkable landmark in the history of land plants. A developing seed contains three genetically distinct structures: the embryo, the nourishing tissue, and the seed coat. While fertilization is necessary to initiate seed development in most plant species, apomicts have evolved mechanisms allowing seed formation independently of fertilization. Despite their socio-economical relevance, the molecular mechanisms driving seed development have only recently begun to be understood. Here we review the current knowledge on the role of the hormone auxin for the initial development of the three seed structures and as a trigger of fertilization-independent seed development.


Assuntos
Ácidos Indolacéticos/metabolismo , Sementes/embriologia , Padronização Corporal , Endosperma/embriologia , Endosperma/metabolismo , Frutas/crescimento & desenvolvimento , Sementes/metabolismo , Transdução de Sinais
3.
Plant J ; 2024 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-38709819

RESUMO

The evolutionary and ecological success of spermatophytes is intrinsically linked to the seed habit, which provides a protective environment for the initial development of the new generation. This environment includes an ephemeral nourishing tissue that supports embryo growth. In gymnosperms this tissue originates from the asexual proliferation of the maternal megagametophyte, while in angiosperms it is a product of fertilization, and is called the endosperm. The emergence of these nourishing tissues is of profound evolutionary value, and they are also food staples for most of the world's population. Here, using Orthofinder to infer orthologue genes among newly generated and previously published datasets, we provide a comparative transcriptomic analysis of seed nourishing tissues from species of several angiosperm clades, including those of early diverging lineages, as well as of one gymnosperm. Our results show that, although the structure and composition of seed nourishing tissues has seen significant divergence along evolution, there are signatures that are conserved throughout the phylogeny. Conversely, we identified processes that are specific to species within the clades studied, and thus illustrate their functional divergence. With this, we aimed to provide a foundation for future studies on the evolutionary history of seed nourishing structures, as well as a resource for gene discovery in future functional studies.

4.
J Endocrinol Invest ; 46(7): 1459-1464, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-36645638

RESUMO

PURPOSE: Simultaneous pancreas-kidney transplantation (SPKT) remains the best treatment option in patients with type 1 diabetes and chronic kidney failure. There are only a few studies addressing the potential ischemic deterioration of peripheral arterial disease (PAD) due to blood diverting from the iliac artery to the kidney graft. We aimed to evaluate diabetic foot lesions and PAD evolution in SPKT recipients and investigate if they are more frequent in ipsilateral lower limb of kidney graft. METHODS: We developed a retrospective cohort, including patients submitted to SPKT in our tertiary center, between 2000 and 2017. Diabetic foot lesions and PAD frequencies were compared in the period before and after transplantation. RESULTS: Two hundred and eleven patients were included, 50.2% (n = 106) female, with a median age at transplantation of 35 years (IQR 9). After a median follow-up period of 10 years (IQR 7), patient, kidney, and pancreatic graft survival were 90.5% (n = 191), 83.4% (n = 176), and 74.9% (n = 158), respectively. Before transplant, 2.8% (n = 6) had PAD and 5.3% (n = 11) had history of foot lesions. In post-transplant period, 17.1% (n = 36) patients presented PAD and 25.6% (n = 54) developed diabetic foot ulcers, 47.6% (n = 35) of which in the ipsilateral and 53.3% (n = 40) in the contralateral lower limb of the kidney graft (p = 0.48). Nine patients (4.3%) underwent major lower limb amputation, 3 (30%) ipsilateral and 7 (70%) contralateral to the kidney graft (p = 0.29). CONCLUSIONS: Diabetic foot lesions were not more frequent in the ipsilateral lower limb of the kidney graft, therefore downgrading the 'steal syndrome' role in these patients.


Assuntos
Diabetes Mellitus Tipo 1 , Pé Diabético , Transplante de Rim , Doença Arterial Periférica , Humanos , Feminino , Criança , Pé Diabético/etiologia , Transplante de Rim/efeitos adversos , Estudos Retrospectivos , Doença Arterial Periférica/etiologia , Pâncreas , Resultado do Tratamento
5.
Appl Microbiol Biotechnol ; 105(11): 4635-4648, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34059939

RESUMO

Currently, the lack of reliable strategies for the diagnosis and treatment of cancer makes the identification and characterization of new therapeutic targets a pressing matter. Several studies have proposed the Six Transmembrane Epithelial Antigen of the Prostate 1 (STEAP1) as a promising therapeutic target for prostate cancer. Although structural and functional studies may provide deeper insights on the role of STEAP1 in cancer, such techniques require high amounts of purified protein through biotechnological processes. Based on the results presented, this work proposes the application, for the first time, of a fed-batch profile to improve STEAP1 biosynthesis in mini-bioreactor Komagataella pastoris X-33 Mut+ methanol-induced cultures, by evaluating three glycerol feeding profiles-constant, exponential, and gradient-during the pre-induction phase. Interestingly, different glycerol feeding profiles produced differently processed STEAP1. This platform was optimized using a combination of chemical chaperones for ensuring the structural stabilization and appropriate processing of the target protein. The supplementation of culture medium with 6 % (v/v) DMSO and 1 M proline onto a gradient glycerol/constant methanol feeding promoted increased biosynthesis levels of STEAP1 and minimized aggregation events. Deglycosylation assays with peptide N-glycosidase F showed that glycerol constant feed is associated with an N-glycosylated pattern of STEAP1. The biological activity of recombinant STEAP1 was also validated, once the protein enhanced the proliferation of LNCaP and PC3 cancer cells, in comparison with non-tumoral cell cultures. This methodology could be a crucial starting point for large-scale production of active and stable conformation of recombinant human STEAP1. Thus, it could open up new strategies to unveil the structural rearrangement of STEAP1 and to better understand the biological role of the protein in cancer onset and progression.


Assuntos
Antígenos de Neoplasias/biossíntese , Glicerol , Metanol , Oxirredutases/biossíntese , Proteínas Recombinantes/biossíntese , Humanos , Pichia , Regiões Promotoras Genéticas , Saccharomycetales
6.
Int Endod J ; 54(8): 1362-1368, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33760261

RESUMO

AIM: To compare microcrack formation in roots of extracted teeth after the shaping of straight and curved root canals with hand, rotary and reciprocating files using micro-computed tomographic (micro-CT) analysis. METHODOLOGY: Thirty straight mandibular incisors and 30 severely curved mesial roots of mandibular molars were randomly divided into 6 experimental groups (n = 10) according to the systems used for the root canal preparation and the root canal curvature: ProTaper Universal for Hand Use (Dentsply Sirona, Ballaigues, Switzerland), HyFlex EDM (Coltene-Whaledent, Altstätten, Switzerland) and Reciproc Blue (VDW, Munich, Germany) files used in mandibular incisors (straight canals) and mesial roots of mandibular molars (curved canals). The roots were imaged with micro-CT scanning at an isotropic resolution of 14 µm before and after root canal preparation, and the cross-sectional images generated were assessed to detect microcracks. RESULTS: All dentinal defects identified after root canal preparation were already present before instrumentation, and no new microcracks were detected. Dentinal microcracks were present in 19% (ProTaper Universal for Hand Use), 11% (Hyflex EDM) and 23% (Reciproc Blue) of the cross-sections when the instrumentation was performed in mandibular incisors. Instrumentation of mandibular molars revealed microcracks in 15% (ProTaper Universal for Hand Use), 16% (Hyflex EDM) and 17% (Reciproc Blue) of the cross-sections. CONCLUSIONS: Preparation of straight and curved root canals with ProTaper Universal for Hand Use, HyFlex EDM and Reciproc Blue systems did not produce microcracks in extracted teeth when evaluated with micro-CT.


Assuntos
Cavidade Pulpar , Preparo de Canal Radicular , Estudos Transversais , Cavidade Pulpar/diagnóstico por imagem , Alemanha , Microtomografia por Raio-X
7.
Anim Genet ; 50(2): 150-153, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30644110

RESUMO

Genome-wide association studies (GWASes) have been performed to search for genomic regions associated with residual feed intake (RFI); however inconsistent results have been obtained. A meta-analysis may improve these results by decreasing the false-positive rate. Additionally, pathway analysis is a powerful tool that complements GWASes, as it enables identification of gene sets involved in the same pathway that explain the studied phenotype. Because there are no reports on GWAS pathways-based meta-analyses for RFI in beef cattle, we used several GWAS results to search for significant pathways that may explain the genetic mechanism underlying this trait. We used an efficient permutation hypothesis test that takes into account the linkage disequilibrium patterns between SNPs and the functional feasibility of the identified genes over the whole genome. One significant pathway (valine, leucine and isoleucine degradation) related to RFI was found. The three genes in this pathway-methylcrotonoyl-CoA carboxylase 1 (MCCC1), aldehyde oxidase 1 (AOX1) and propionyl-CoA carboxylase alpha subunit (PCCA)-were found in three different studies. This same pathway was also reported in a transcriptome analysis from two cattle populations divergently selected for high and low RFI. We conclude that a GWAS pathway-based meta-analysis can be an appropriate method to uncover biological insights into RFI by combining useful information from different studies.


Assuntos
Bovinos/fisiologia , Ingestão de Alimentos/genética , Estudo de Associação Genômica Ampla/veterinária , Desequilíbrio de Ligação , Polimorfismo de Nucleotídeo Único , Ração Animal/análise , Animais , Bovinos/genética , Marcadores Genéticos
8.
PLoS Genet ; 12(4): e1005924, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-27100965

RESUMO

Several pathways control time to flowering in Arabidopsis thaliana through transcriptional and posttranscriptional gene regulation. In recent years, mRNA processing has gained interest as a critical regulator of flowering time control in plants. However, the molecular mechanisms linking RNA splicing to flowering time are not well understood. In a screen for Arabidopsis early flowering mutants we identified an allele of BRR2a. BRR2 proteins are components of the spliceosome and highly conserved in eukaryotes. Arabidopsis BRR2a is ubiquitously expressed in all analyzed tissues and involved in the processing of flowering time gene transcripts, most notably FLC. A missense mutation of threonine 895 in BRR2a caused defects in FLC splicing and greatly reduced FLC transcript levels. Reduced FLC expression increased transcription of FT and SOC1 leading to early flowering in both short and long days. Genome-wide experiments established that only a small set of introns was not correctly spliced in the brr2a mutant. Compared to control introns, retained introns were often shorter and GC-poor, had low H3K4me1 and CG methylation levels, and were often derived from genes with a high-H3K27me3-low-H3K36me3 signature. We propose that BRR2a is specifically needed for efficient splicing of a subset of introns characterized by a combination of factors including intron size, sequence and chromatin, and that FLC is most sensitive to splicing defects.


Assuntos
Proteínas de Arabidopsis/fisiologia , Arabidopsis/fisiologia , Flores/fisiologia , Proteínas de Domínio MADS/genética , Splicing de RNA , Sequência de Aminoácidos , Animais , Arabidopsis/genética , Proteínas de Arabidopsis/química , Proteínas de Arabidopsis/genética , Genes de Plantas , Humanos , Íntrons , Dados de Sequência Molecular , Mutação , RNA Mensageiro/genética , Homologia de Sequência de Aminoácidos
9.
Biochim Biophys Acta ; 1859(2): 393-404, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26732823

RESUMO

DREB1/CBF genes, known as major regulators of plant stress responses, are rapidly and transiently induced by low temperatures. Using a yeast one-hybrid screening, we identified a putative Phytochrome-Interacting bHLH Factor (OsPIF14), as binding to the OsDREB1B promoter. bHLH proteins are able to bind to hexameric E-box (CANNTG) or N-box (CACG(A/C)G) motifs, depending on transcriptional activity. We have shown that OsPIF14 binds to the OsDREB1B promoter through two N-boxes and that the flanking regions of the hexameric core are essential for protein-DNA interaction and stability. We also showed that OsPIF14 down-regulates OsDREB1B gene expression in rice protoplasts, corroborating the OsPIF14 repressor activity observed in the transactivation assays using Arabidopsis protoplasts. In addition, we showed that OsPIF14 is indeed a phytochrome interacting factor, which preferentially binds to the active form (Pfr) of rice phytochrome B. This raises the possibility that OsPIF14 activity might be modulated by light. However, we did not observe any regulation of the OsDREB1B gene expression by light under control conditions. Moreover, OsPIF14 gene expression was shown to be modulated by different treatments, such as drought, salt, cold and ABA. Interestingly, OsPIF14 showed also a specific cold-induced alternative splicing. All together, these results suggest the possibility that OsPIF14 is involved in cross-talk between light and stress signaling through interaction with the OsDREB1B promoter. Although in the absence of stress, OsDREB1B gene expression was not regulated by light, given previous reports, it remains possible that OsPIF14 has a role in light modulation of stress responses.


Assuntos
Proteínas de Arabidopsis/genética , Oryza/genética , Fitocromo B/genética , Proteínas de Plantas/genética , Estresse Fisiológico/genética , Fatores de Transcrição/genética , Sequência de Aminoácidos/genética , Proteínas de Arabidopsis/metabolismo , Temperatura Baixa , Proteínas de Ligação a DNA/genética , Secas , Regulação da Expressão Gênica de Plantas , Oryza/fisiologia , Fitocromo B/metabolismo , Plantas Geneticamente Modificadas , Regiões Promotoras Genéticas , Fatores de Transcrição/metabolismo
10.
Clin Otolaryngol ; 41(1): 21-4, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26017923

RESUMO

OBJECTIVES: Sino-Nasal Outcome Test-22 is a questionnaire that evaluates the specific quality of life in chronic rhinosinusitis and was widely used in scientific literature. The aim of our study was to translate and culturally adapt Sino-Nasal Outcome Test-22 for the Portuguese reality and validate the version obtained for use in Portugal. DESIGN: We translate Sino-Nasal Outcome Test-22 into European Portuguese according to the methodology recommended by the scientific literature. After translation, we proceeded with the evaluation of the questionnaire regarding its feasibility, reliability (internal consistency and test-retest reproducibility) and discriminant validity. Statistical analysis was performed using spss 22.0. SETTING: Patients treated at a single institute. PARTICIPANTS: We applied Sino-Nasal Outcome Test-22 questionnaire to 15 volunteers with no nasal or sinus disease and to 50 patients with chronic rhinosinusitis. MAIN OUTCOME MEASURES: Feasibility, reliability (internal consistency and test-retest reproducibility) and discriminant validity. RESULTS: We observed good internal consistency, with general Cronbach's α coefficient of 0.935, good test-retest reproducibility (32.5 versus 32, P < 0.001), with Pearson coefficient of 0.99 (P < 0.001) and Cohen Kappa coefficient of 0.898. The discriminant validity of the Portuguese version of Sino-Nasal Outcome Test-22 was confirmed by applying the Mann-Whitney U-test (P < 0.001). CONCLUSIONS: Until now, there were no validated questionnaires to evaluate quality of life in patients with chronic rhinosinusitis in Portugal. Translation and validation of Sino-Nasal Outcome Test-22 in Portugal will allow a more consistent assessment of the specific quality of life of these patients and the comparison with international data. Thus, we recommend this version for use with the Portuguese population with chronic rhinosinusitis.


Assuntos
Qualidade de Vida , Rinite/fisiopatologia , Sinusite/fisiopatologia , Adaptação Fisiológica , Doença Crônica , Estudos de Viabilidade , Humanos , Portugal , Reprodutibilidade dos Testes , Inquéritos e Questionários , Tradução
11.
Biochem Soc Trans ; 42(2): 358-63, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24646244

RESUMO

The evolution of seeds was a major reason for the rise of angiosperms to ecological dominance. Seeds of angiosperms are composed of three main structures: the embryo, which will give rise to the next generation; the endosperm, a nurturing tissue whose main function is to deliver nutrients from the mother plant to the embryo; and the seed coat (or testa), a tissue that is derived from the maternal integuments and which provides support and protection to the growing embryo. All three seed components need to exchange signals to ensure co-ordinated growth and development. The present review discusses the structure of the seed coat, its interaction with the endosperm, and bidirectional signalling events between endosperm and seed coat that co-ordinate growth of both tissues. Angiosperm seeds are not only of evolutionary significance, but also of major agronomic importance, demanding a thorough understanding of the events governing seed growth and development.


Assuntos
Endosperma/metabolismo , Sementes/metabolismo , Endosperma/genética , Endosperma/crescimento & desenvolvimento , Regulação da Expressão Gênica de Plantas/genética , Regulação da Expressão Gênica de Plantas/fisiologia , Proteínas do Grupo Polycomb/genética , Proteínas do Grupo Polycomb/metabolismo , Sementes/genética , Sementes/crescimento & desenvolvimento
12.
Artigo em Inglês | MEDLINE | ID: mdl-24892298

RESUMO

In bottom-up proteomics approaches, the enzymatic proteolysis step before mass spectrometry (MS) analysis is of crucial importance, as only the efficient digestion of the protein will ensure its accurate quantification. The structural and chemical alterations occurring upon protein oxidation may decrease the efficiency of trypsin digestion, compromising the ensuing MS analysis. Herein, the efficiency of the trypsin digestion of oxidized bovine serum albumin (BSA) was assessed by protein-sequence coverage and the exponentially modified protein abundance index (emPAI) algorithm, allowing a comparison of protein abundance in samples with different levels of oxidation. Despite the extensive oxidation induced to BSA, verified by analysis of protein carbonyls, no significant difference in the yield of tryptic peptides from oxidized samples could be observed by nano-high-performance liquid chromatography (HPLC) and nano-HPLC7-electrospray ionization-MS analysis. After a database search, similar protein-sequence coverage rates were obtained for both treated and control samples. Thus, exponentially modified protein abundance index scores confirmed that, regardless of being oxidized, the same amount of BSA was present in the sodium dodecyl sulfate/polyacrylamide gel electrophoresis bands excised for digestion. The obtained results show that the digestion of the control and oxidized samples were similar, leading to the conclusion that in-gel proteolysis is not a main hindrance for the identification and quantification of oxidized proteins by MS.


Assuntos
Proteômica/métodos , Soroalbumina Bovina/análise , Soroalbumina Bovina/metabolismo , Espectrometria de Massas por Ionização por Electrospray/métodos , Tripsina/metabolismo , Animais , Bovinos , Cromatografia Líquida de Alta Pressão/métodos , Oxirredução , Espectrofotometria Ultravioleta/métodos
13.
Plant Reprod ; 2024 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-38836892

RESUMO

KEY MESSAGE: The DNA methylation status at an epigenetic quantitative trait locus in the Arabidopsis chromosome 2 is linked to the formation of apomictic-like endosperms. Seed development in most angiosperms is coupled to fertilization of the maternal gametes by two sperm cells. However, apomictic species can reproduce asexually via seeds. This trait is of great agricultural interest, as it would fix complex genotypes and allow for pollen-independent seed production. However, engineering full apomixis requires three independent processes: apomeiosis, parthenogenesis and autonomous endosperm development. While the first two have been successfully engineered in some crops, the formation of autonomous endosperms remains a challenge. Although it is known that this trait is under epigenetic control, such as of DNA methylation, the underlying mechanisms remain mostly undiscovered. Here, using epigenetic recombinant inbred lines, we identified an epigenetic quantitative trait locus in the Arabidopsis chromosome 2, which correlates with permissiveness for the formation of asexual seeds: hypomethylation at this genomic region allows the formation of larger autonomous endosperms. Importantly, the methylation at this locus only correlates with asexual seed size, and not to the size of sexual seeds or that of other organs. With this, we aim to show that screening for epialleles is a promising strategy to uncover loci underlying relevant traits and could pave the way to identifying genes necessary for the engineering of apomixis.

14.
Clinics (Sao Paulo) ; 79: 100356, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38608555

RESUMO

OBJECTIVE: This study aims to correlate the RAPID score with the 3-month survival and surgical results of patients undergoing lung decortication with stage III pleural empyema. METHODS: This was a retrospective study with the population of patients with pleural empyema who underwent pulmonary decortication between January 2019 and June 2022. Data were collected from the institution's database, and patients were classified as low, medium, and high risk according to the RAPID score. The primary outcome was 3-month mortality. Secondary outcomes were the length of hospital stay, readmission rate, and the need for pleural re-intervention. RESULTS: Of the 34 patients with pleural empyema, according to the RAPID score, patients were stratified into low risk (23.5 %), medium risk (47.1 %), and high risk (29.4 %). The high-risk group had a 3-month mortality of 40 %, while the moderate-risk group had a 6.25 % and the low-risk group had no deaths within 90 days, confirming a good correlation with the RAPID score (p < 0.05). Sensitivity and specificity for the primary outcome in the high-risk score were 80.0 % and 79.3 %, respectively. The secondary outcomes did not reach statistical significance. CONCLUSIONS: In this retrospective series, the RAPID score had a good correlation with 3-month mortality in patients undergoing lung decortication. The morbidity indicators did not reach statistical significance. The present data justifies further studies to explore the capacity of the RAPID score to be used as a selection tool for treatment modality in patients with stage III pleural empyema.


Assuntos
Empiema Pleural , Tempo de Internação , Complicações Pós-Operatórias , Humanos , Empiema Pleural/mortalidade , Empiema Pleural/cirurgia , Masculino , Estudos Retrospectivos , Feminino , Pessoa de Meia-Idade , Idoso , Complicações Pós-Operatórias/mortalidade , Tempo de Internação/estatística & dados numéricos , Adulto , Medição de Risco/métodos , Fatores de Risco , Resultado do Tratamento
15.
Plant Mol Biol ; 83(4-5): 351-63, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23780733

RESUMO

Plants can cope with adverse environmental conditions through the activation of stress response signalling pathways, in which the proteasome seems to play an important role. However, the mechanisms underlying the proteasome-mediated stress response in rice are still not fully understood. To address this issue, we have identified a rice E3-ubiquitin ligase, OsHOS1, and characterized its role in the modulation of the cold stress response. Using a RNA interference (RNAi) transgenic approach we found that, under cold conditions, the RNAi::OsHOS1 plants showed a higher expression level of OsDREB1A. This was correlated with an increased amount of OsICE1, a master transcription factor of the cold stress signalling. However, the up-regulation of OsDREB1A was transient and the transgenic plants did not show increased cold tolerance. Nevertheless, we could confirm the interaction of OsHOS1 with OsICE1 by Yeast-Two hybrid and bi-molecular fluorescence complementation in Arabidopsis protoplasts. Moreover, we could also determine through an in vitro degradation assay that the higher amount of OsICE1 in the transgenic plants was correlated with a lower amount of OsHOS1. Hence, we could confirm the involvement of the proteasome in this response mechanism. Taken together our results confirm the importance of OsHOS1, and thus of the proteasome, in the modulation of the cold stress signalling in rice.


Assuntos
Resposta ao Choque Frio , Regulação Enzimológica da Expressão Gênica/genética , Oryza/enzimologia , Transdução de Sinais , Ubiquitina-Proteína Ligases/genética , Sequência de Aminoácidos , Arabidopsis/genética , Arabidopsis/metabolismo , Arabidopsis/fisiologia , Regulação da Expressão Gênica de Plantas/genética , Inativação Gênica , Dados de Sequência Molecular , Oryza/genética , Oryza/fisiologia , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas , Complexo de Endopeptidases do Proteassoma/metabolismo , Proteólise , Interferência de RNA , Proteínas Recombinantes de Fusão , Alinhamento de Sequência , Ativação Transcricional , Técnicas do Sistema de Duplo-Híbrido , Ubiquitina-Proteína Ligases/metabolismo , Ubiquitinação , Regulação para Cima
16.
Plant Mol Biol ; 82(4-5): 439-55, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23703395

RESUMO

High salinity causes remarkable losses in rice productivity worldwide mainly because it inhibits growth and reduces grain yield. To cope with environmental changes, plants evolved several adaptive mechanisms, which involve the regulation of many stress-responsive genes. Among these, we have chosen OsRMC to study its transcriptional regulation in rice seedlings subjected to high salinity. Its transcription was highly induced by salt treatment and showed a stress-dose-dependent pattern. OsRMC encodes a receptor-like kinase described as a negative regulator of salt stress responses in rice. To investigate how OsRMC is regulated in response to high salinity, a salt-induced rice cDNA expression library was constructed and subsequently screened using the yeast one-hybrid system and the OsRMC promoter as bait. Thereby, two transcription factors (TFs), OsEREBP1 and OsEREBP2, belonging to the AP2/ERF family were identified. Both TFs were shown to bind to the same GCC-like DNA motif in OsRMC promoter and to negatively regulate its gene expression. The identified TFs were characterized regarding their gene expression under different abiotic stress conditions. This study revealed that OsEREBP1 transcript level is not significantly affected by salt, ABA or severe cold (5 °C) and is only slightly regulated by drought and moderate cold. On the other hand, the OsEREBP2 transcript level increased after cold, ABA, drought and high salinity treatments, indicating that OsEREBP2 may play a central role mediating the response to different abiotic stresses. Gene expression analysis in rice varieties with contrasting salt tolerance further suggests that OsEREBP2 is involved in salt stress response in rice.


Assuntos
Oryza/metabolismo , Fator de Transcrição AP-2/metabolismo , Ácido Abscísico/farmacologia , Secas , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Regulação da Expressão Gênica de Plantas/genética , Oryza/efeitos dos fármacos , Oryza/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Cloreto de Sódio/farmacologia , Fator de Transcrição AP-2/genética
17.
Allergy ; 68(8): 1073-5, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23889600

RESUMO

BACKGROUND: Endothelial (EMPs) and platelet microparticles (PMPs) have been studied as biomarkers in several inflammatory diseases and as central players in intercellular communication. METHODS: In this cross-sectional study, we aimed to assess microparticle levels in asthma. Circulating microparticles and inflammatory and angiogenic markers were assessed by clinical and laboratorial evaluation, flow cytometry, and immunoassays, in a group of 20 asthmatic and 15 nonasthmatic subjects. RESULTS: Circulating levels of PMPs (either CD31+/42b+ or CD31+/42b+/AnV+) were significantly increased in asthmatics (P = 0.021) even after adjustment for confounders. Apoptotic EMPs (CD31+/42b--/AnV+) were significantly increased before (P = 0.005) but not after adjustments (P = 0.117). CONCLUSIONS: We propose that PMPs may be putative asthma biomarkers, playing a role in asthma pathophysiology.


Assuntos
Asma/imunologia , Plaquetas/imunologia , Micropartículas Derivadas de Células/imunologia , Regulação para Cima/imunologia , Adulto , Asma/sangue , Asma/patologia , Biomarcadores/sangue , Biomarcadores/metabolismo , Plaquetas/metabolismo , Plaquetas/patologia , Micropartículas Derivadas de Células/metabolismo , Micropartículas Derivadas de Células/patologia , Feminino , Humanos , Inflamação/sangue , Inflamação/imunologia , Inflamação/patologia , Masculino , Pessoa de Meia-Idade , Ativação Plaquetária/imunologia
18.
Int J Oral Maxillofac Surg ; 52(4): 442-450, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35985910

RESUMO

The aims of this cohort study were to compare the mandibular morphology between patients with Robin sequence (RS) and controls, and to examine the effects of mandibular distraction osteogenesis (MDO) using different vectors. Measurements of the mandibles of 80 patients with RS and 46 controls aged< 90 days were made using computed tomography. The data were compared among isolated RS patients (n = 58), syndromic RS patients (n = 22), and controls. Patients with RS exhibited significantly shorter ramus and body lengths and larger symphyseal angles than controls (all P < 0.001). Patients with isolated RS had shorter body lengths (P < 0.001), while syndromic patients had shorter ramus and body lengths (both P < 0.001) than controls. Seventy RS patients underwent MDO. Pre-MDO (n = 37) and post-MDO (n = 29) mandibular measurements were compared between patients undergoing MDO with a vertical vector and those undergoing MDO with a horizontal vector. Polysomnography data from part of the cohort highlighted the effectiveness of both vectors. MDO with a horizontal vector conferred 11% and 36% increases in ramus and body length, respectively, while these increases were 34% and 27.5%, respectively, with a vertical vector. MDO with a vertical vector was effective in lengthening ramus and body components and should be considered in the presence of ramus hypoplasia.


Assuntos
Obstrução das Vias Respiratórias , Osteogênese por Distração , Síndrome de Pierre Robin , Humanos , Lactente , Estudos de Coortes , Estudos Retrospectivos , Osteogênese por Distração/métodos , Mandíbula/anormalidades , Polímeros , Resultado do Tratamento
19.
J Exp Bot ; 63(10): 3643-56, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22412187

RESUMO

Plants have evolved several mechanisms in order to cope with adverse environmental conditions. The transcription factors (TFs) belonging to the DREB1/CBF subfamily have been described as major regulators of the plant responses to different abiotic stresses. This study focused on the rice gene OsDREB1B, initially described as highly and specifically induced by cold. However, here it is shown that OsDREB1B is not only induced by low temperatures, but also by drought and mechanical stress. In order to identify novel TFs that bind to its promoter, a yeast one-hybrid system was used to screen a cold-induced cDNA expression library. Thereby seven novel Zn-finger TFs were identified that bind to the promoter of OsDREB1B. Among them, there were four Zn-finger homeodomain (ZF-HD) and three C(2)H(2)-type Zn-finger TFs. Gene expression studies showed that these TFs are differentially regulated at transcriptional level by different abiotic stress conditions, which is illustrative of the crosstalk between stress signalling pathways. Protein-protein interaction studies revealed the formation of homo- and heterodimers among the ZF-HD TFs identified, but not for the C(2)H(2)-type. Using a transactivation assay in Arabidopsis protoplasts, all the TFs identified repressed the expression of the reporter gene, driven by the promoter of OsDREB1B. This assay also showed that the dimerization observed between the ZF-HD TFs may play a role on their transactivation activity. The results here presented suggest a prominent role of Zn-finger TFs in the regulation of OsDREB1B.


Assuntos
Regulação da Expressão Gênica de Plantas , Oryza/fisiologia , Proteínas de Plantas/química , Proteínas de Plantas/metabolismo , Fatores de Transcrição/química , Fatores de Transcrição/metabolismo , Dedos de Zinco , Genes Reguladores , Oryza/química , Oryza/genética , Proteínas de Plantas/genética , Regiões Promotoras Genéticas , Estresse Fisiológico , Fatores de Transcrição/genética
20.
Int J Med Inform ; 165: 104832, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35842978

RESUMO

BACKGROUND: Limited research has examined mobile phone-based platforms for survey recruitment, especially during the COVID-19 pandemic in Brazil. Our objective was to investigate the feasibility and representativeness of mobile phone-based advertisement during a preliminary study about COVID-19 vaccine hesitation in Brazil. Moreover, we evaluate whether the older population can be reached through mobile phone-based platforms of the survey. METHODS: We conducted a study in December 2021 based on a preliminary survey about the COVID-19 vaccine hesitation in Assis, Brazil, Sao Paulo state. From a list of the adult population hesitant about the second dose of the COVID-19 vaccine, we sent a mobile phone-based advertisement inviting the participants to answer the survey for one week. The respondent's data were collected in a Google form platform. The comparison between the target population and the respondents was made using the Chi-squared test and the Welch's test, using a P-value of 0.05 as significative. RESULTS: The response rate was 9.99% after one week. The mean age of the respondent group was 33.97 (SD 14.99) and 35.05 (SD 14.19) of the population, with a P-value of 0.192 and a Cohen's d coefficient of 0.0754, corresponding to a small effect size between groups. We demonstrate that the mobile phone-based survey is a feasible and representative strategy during the pandemics in Brazil. Moreover, the older population respondent was representative. CONCLUSION: We achieved a representative sample of respondents using the mobile phone-based survey in Brazil. Furthermore, it was representative of all sociodemographic and health characteristics assessed. Finally, these findings suggest that the method is a highly feasible and economical means of recruiting for survey research.


Assuntos
COVID-19 , Telefone Celular , Envio de Mensagens de Texto , Adulto , Brasil/epidemiologia , COVID-19/epidemiologia , COVID-19/prevenção & controle , Vacinas contra COVID-19 , Estudos Transversais , Humanos , Pandemias/prevenção & controle
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