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1.
Orphanet J Rare Dis ; 19(1): 50, 2024 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-38326833

RESUMO

BACKGROUND: Reducing delayed diagnosis is a significant healthcare priority for individuals with rare diseases. Fibrous Dysplasia/ McCune Albright Syndrome (FD/MAS) is a rare bone disease caused by somatic activation mutations of NASA. FD/MAS has a broad clinical phenotype reflecting variable involvement of bone, endocrine and other tissues, distribution and severity. The variable phenotype is likely to prolong the diagnostic journey for patients further. AIM: To describe the time from symptom onset to final diagnosis in individuals living with FDMAS. METHODS: We used the UK-based RUDY research database ( www.rudystudy.org ), where patients self-report their diagnosis of FD/MAS. Participants are invited to complete the diagnostic journey based on the EPIRARE criteria. RESULTS: 51 individuals diagnosed with FD/MAS were included in this analysis. Among them, 70% were female, and the median age was 51.0 years (IQR 34.5-57.5]. 12 (35%) individuals reported McCune Albright Syndrome, 11 (21.6%) craniofacial and 11(21.6%) for each of poly- and mono-ostotic FD and 6 (11.8%) did not know their type of FD/MAS. Pain was the commonest first symptom (58.8%), and 47.1% received another diagnosis before the diagnosis of FD/MAS. The median time to final diagnosis from the first symptom was two years with a wide IQR (1,18) and range (0-59 years). Only 12 (23.5%) of individuals were diagnosed within 12 months of their first symptoms. The type of FD/MAS was not associated with the reported time to diagnosis. Significant independent predictors of longer time to final diagnosis included older current age, younger age at first symptom and diagnosis after 2010. CONCLUSION: Individuals with FDMAS have a variable time to diagnosis that can span decades. This study highlights the need for further research on how to improve diagnostic pathways within Orthopaedic and Ear, Nose and Throat (ENT)/Maxillofacial services. Our data provides a baseline to assess the impact of novel NHS diagnostic networks on reducing the diagnostic odyssey.


Assuntos
Displasia Fibrosa Óssea , Displasia Fibrosa Poliostótica , Humanos , Feminino , Pessoa de Meia-Idade , Masculino , Displasia Fibrosa Poliostótica/diagnóstico , Displasia Fibrosa Óssea/diagnóstico , Fenótipo
2.
Front Oncol ; 13: 1282569, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38098501

RESUMO

Introduction: Late presentation of multiple myeloma (MM) heightens the risk of complication risks, including end-organ damage. This study aimed to: 1) detail the diagnostic journey of MM patients, encompassing symptoms, initial diagnoses, and healthcare professionals met; 2) establish the median duration from symptom onset to MM diagnosis; and 3) examine factors linked to timely MM diagnosis within 12 weeks. Methods: A total of 300 adults self-reporting MM were analysed from the Rare and Undiagnosed Diseases cohort Study (RUDY). The RUDY study is a web-based platform, where participants provide dynamic consent and self-report their MM diagnosis and information about their diagnostic journey. This includes the estimated date of initial potential first symptoms, descriptions of these symptoms, the healthcare professionals they consulted, and other diagnoses received before the MM diagnosis. Descriptive statistics, combinatorial analyses and logistic regression analyses were used to describe and examine the diagnostic journey of individuals with MM. Results: Overall, 52% of the participants reported other diagnoses before MM diagnosis, with musculoskeletal disorders (47.8%), such as osteoporosis, costochondritis, or muscle strains, being the most common. The most prevalent initial reported symptom was back pain/vertebral fractures (47%), followed by chest/shoulder pain, including rib pain and fractures (20%), and fatigue/tiredness (19.7%). 40% of participants were diagnosed by direct referral from primary care to haematology without seeing other healthcare professionals whilst 60% consulted additional specialists before diagnosis. The median time from symptom onset to MM diagnosis was 4 months (IQR 2-10 months, range 0-172). Seeing an Allied Healthcare Professional such as a physiotherapist, chiropractor or an osteopath (OR = 0.25, 95% CI [0.12, 0.47], p <0.001), experiencing infection symptoms (OR = 0.32, 95% CI [0.13, 0.76], p = 0.013), and having chest or shoulder pain (OR = 0.45, 95% CI [0.23, 0.86], p = 0.020) were associated with a lower likelihood of being diagnosed with MM within 12 weeks. Older age (OR = 1.04, 95% CI [1.02, 1.07], p = 0.001) was associated with a higher likelihood of diagnosis within 12 weeks. Discussion: Developing resources for allied health professionals may improve early recognition of MM.

3.
Euphytica ; 215(7): 117, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31274875

RESUMO

The root-knot nematode Meloidogyne graminicola is a serious pest in rice affecting production in many rice growing areas. Natural host resistance is an attractive control strategy because the speed of the parasite's life cycle and the broad host range it attacks make other control measures challenging. Although resistance has been found in the domesticated African rice Oryza glaberrima and the wild rice species O. longistaminata, the introgression of resistance genes to Asian rice O. sativa is challenging. Resistance due to a major gene in O. sativa would greatly aid breeding. Recently two accessions resistant to M. graminicola have been identified in a screen of 332 diverse O. sativa cultivars. In this study, these two resistant cultivars, LD 24 (an indica from Sri Lanka) and Khao Pahk Maw (an aus from Thailand), were crossed with a moderately susceptible cultivar, Vialone Nano (a temperate japonica from Italy). Approximately 175 F2 progeny of both populations were screened for susceptibility to M. graminicola infection. Between 20 and 23 individuals with highest and lowest galls per plants were pooled to make susceptible and resistant bulks which were sequenced to conduct bulked segregant analysis using the QTL-seq method. This revealed a nematode resistance locus from 23 Mbp to the bottom of rice chromosome 11 in both crosses suggesting a rare introgression of the same locus is responsible for resistance in both cultivars. While this information can be used in marker-assisted breeding, analysis of available SNP data revealed candidate loci and genes worthy of further investigation for gene identification.

4.
Front Plant Sci ; 10: 633, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31156686

RESUMO

If water saving methods of rice management are to be adopted, the interaction between rice plants and arbuscular mycorrhizal (AM) fungi will grow in agronomic significance. As yet there are very few studies on the interaction between rice and AM fungi and none on host genetics. A subset 334 cultivars from the Rice Diversity Panel 1 were grown in 250 L boxes filled with phosphorus (P) deficient aerobic soil without addition, with added rock phosphate and with rock phosphate and the AM fungus Rhizophagus irregularis. Statistical analysis of position of plants revealed a positive effect of their neighbors on their dry weight which was stronger in the presence of rock phosphate and even stronger with rock phosphate and AM fungi. A weak but significant difference in the response of cultivars to AM fungus treatment in terms of shoot dry weight (SDW) was revealed. Neighbor hyphal colonization was positively related to a plant's hyphal colonization, providing insights into the way a network of AM fungi interact with multiple hosts. Hyphal colonization ranged from 21 to 89%, and 42% of the variation was explained by rice genotype. Colonization was slightly lower in aus cultivars than other rice subgroups and high in cultivars from the Philippines. Genome wide association (GWA) mapping for hyphal colonization revealed 23 putative quantitative trait loci (QTLs) indicating there is an opportunity to investigate the impact of allelic variation in rice on AM fungal colonization. Using published transcriptomics data for AM response in rice, some promising candidate genes are revealed under these QTLs being a calcium/calmodulin serine/threonine protein kinase at 4.9 Mbp on chromosome 1, two ammonium transporters genes at 24.6 Mbp on chromosome 2 and a cluster of subtilisin genes at 1.2 Mbp on chromosome 4. Future studies should concentrate on the biological significance of genetic variation in rice for AM colonization.

5.
Nat Plants ; 5(4): 358-362, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30936438

RESUMO

In several plant species, inflorescence formation is accompanied by stem elongation. Both processes are accelerated in rice upon perception of shortening days. Here, we show that PREMATURE INTERNODE ELONGATION 1 (PINE1), encoding a rice zinc-finger transcription factor, reduces the sensitivity of the stem to gibberellin (GA). The florigens reduce PINE1 expression to increase stem responsiveness to GA and promote flowering. These data indicate the existence of a regulatory network coordinating flowering and GA-dependent growth.


Assuntos
Oryza/fisiologia , Proteínas de Plantas/fisiologia , Fatores de Transcrição/fisiologia , Flores/crescimento & desenvolvimento , Giberelinas/metabolismo , Oryza/crescimento & desenvolvimento , Oryza/metabolismo , Fotoperíodo , Reguladores de Crescimento de Plantas/metabolismo , Proteínas de Plantas/metabolismo , Caules de Planta/crescimento & desenvolvimento , Caules de Planta/metabolismo , Fatores de Transcrição/metabolismo , Dedos de Zinco/fisiologia
6.
Plant Cell ; 29(11): 2801-2816, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-29042404

RESUMO

Plants measure day or night lengths to coordinate specific developmental changes with a favorable season. In rice (Oryza sativa), the reproductive phase is initiated by exposure to short days when expression of HEADING DATE 3a (Hd3a) and RICE FLOWERING LOCUS T 1 (RFT1) is induced in leaves. The cognate proteins are components of the florigenic signal and move systemically through the phloem to reach the shoot apical meristem (SAM). In the SAM, they form a transcriptional activation complex with the bZIP transcription factor OsFD1 to start panicle development. Here, we show that Hd3a and RFT1 can form transcriptional activation or repression complexes also in leaves and feed back to regulate their own transcription. Activation complexes depend on OsFD1 to promote flowering. However, additional bZIPs, including Hd3a BINDING REPRESSOR FACTOR1 (HBF1) and HBF2, form repressor complexes that reduce Hd3a and RFT1 expression to delay flowering. We propose that Hd3a and RFT1 are also active locally in leaves to fine-tune photoperiodic flowering responses.


Assuntos
Florígeno/metabolismo , Flores/metabolismo , Meristema/metabolismo , Oryza/metabolismo , Proteínas de Plantas/metabolismo , Fatores de Transcrição/metabolismo , Flores/genética , Flores/crescimento & desenvolvimento , Regulação da Expressão Gênica no Desenvolvimento/efeitos da radiação , Regulação da Expressão Gênica de Plantas/efeitos da radiação , Meristema/genética , Meristema/crescimento & desenvolvimento , Oryza/genética , Oryza/crescimento & desenvolvimento , Fotoperíodo , Folhas de Planta/genética , Folhas de Planta/crescimento & desenvolvimento , Folhas de Planta/metabolismo , Proteínas de Plantas/genética , Transdução de Sinais/genética , Transdução de Sinais/efeitos da radiação , Fatores de Transcrição/genética
7.
J Exp Bot ; 67(4): 1191-200, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26552884

RESUMO

The root-knot nematode Meloidogyne graminicola is one of the most serious nematode pests worldwide and represents a major constraint on rice production. While variation in the susceptibility of Asian rice (Oryza sativa) exists, so far no strong and reliable resistance has been reported. Quantitative trait loci for partial resistance have been reported but no underlying genes have been tagged or cloned. Here, 332 accessions of the Rice Diversity Panel 1 were assessed for gall formation, revealing large variation across all subpopulations of rice and higher susceptibility in temperate japonica accessions. Accessions Khao Pahk Maw and LD 24 appeared to be resistant, which was confirmed in large pot experiments where no galls were observed. Detailed observations on these two accessions revealed no nematodes inside the roots 2 days after inoculation and very few females after 17 days (5 in Khao Pahk Maw and <1 in LD 24, in comparison with >100 in the susceptible controls). These two cultivars appear ideal donors for breeding root-knot nematode resistance. A genome-wide association study revealed 11 quantitative trait loci, two of which are close to epistatic loci detected in the Bala x Azucena population. The discussion highlights a small number of candidate genes worth exploring further, in particular many genes with lectin domains and genes on chromosome 11 with homology to the Hordeum Mla locus.


Assuntos
Resistência à Doença , Oryza/genética , Oryza/parasitologia , Doenças das Plantas/genética , Tylenchoidea/fisiologia , Animais , Estudo de Associação Genômica Ampla , Genótipo , Doenças das Plantas/parasitologia , Raízes de Plantas/parasitologia , Locos de Características Quantitativas , Análise de Sequência de DNA
8.
PLoS One ; 10(4): e0124127, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25909711

RESUMO

The rapid progress in rice genotyping must be matched by advances in phenotyping. A better understanding of genetic variation in rice for drought response, root traits, and practical methods for studying them are needed. In this study, the OryzaSNP set (20 diverse genotypes that have been genotyped for SNP markers) was phenotyped in a range of field and container studies to study the diversity of rice root growth and response to drought. Of the root traits measured across more than 20 root experiments, root dry weight showed the most stable genotypic performance across studies. The environment (E) component had the strongest effect on yield and root traits. We identified genomic regions correlated with root dry weight, percent deep roots, maximum root depth, and grain yield based on a correlation analysis with the phenotypes and aus, indica, or japonica introgression regions using the SNP data. Two genomic regions were identified as hot spots in which root traits and grain yield were co-located; on chromosome 1 (39.7-40.7 Mb) and on chromosome 8 (20.3-21.9 Mb). Across experiments, the soil type/ growth medium showed more correlations with plant growth than the container dimensions. Although the correlations among studies and genetic co-location of root traits from a range of study systems points to their potential utility to represent responses in field studies, the best correlations were observed when the two setups had some similar properties. Due to the co-location of the identified genomic regions (from introgression block analysis) with QTL for a number of previously reported root and drought traits, these regions are good candidates for detailed characterization to contribute to understanding rice improvement for response to drought. This study also highlights the utility of characterizing a small set of 20 genotypes for root growth, drought response, and related genomic regions.


Assuntos
Oryza/crescimento & desenvolvimento , Oryza/genética , Mapeamento Cromossômico , Cromossomos de Plantas/genética , Secas , Meio Ambiente , Estudos de Associação Genética , Genoma de Planta , Raízes de Plantas/genética , Raízes de Plantas/crescimento & desenvolvimento , Polimorfismo de Nucleotídeo Único , Locos de Características Quantitativas
9.
J Exp Bot ; 66(7): 2027-39, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25732533

RESUMO

The capacity to discriminate variations in day length allows plants to align flowering with the most favourable season of the year. This capacity has been altered by artificial selection when cultivated varieties became adapted to environments different from those of initial domestication. Rice flowering is promoted by short days when HEADING DATE 1 (Hd1) and EARLY HEADING DATE 1 (Ehd1) induce the expression of florigenic proteins encoded by HEADING DATE 3a (Hd3a) and RICE FLOWERING LOCUS T 1 (RFT1). Repressors of flowering antagonize such induction under long days, maintaining vegetative growth and delaying flowering. To what extent artificial selection of long day repressor loci has contributed to expand rice cultivation to Europe is currently unclear. This study demonstrates that European varieties activate both Hd3a and RFT1 expression regardless of day length and their induction is caused by loss-of-function mutations at major long day floral repressors. However, their contribution to flowering time control varies between locations. Pyramiding of mutations is frequently observed in European germplasm, but single mutations are sufficient to adapt rice to flower at higher latitudes. Expression of Ehd1 is increased in varieties showing reduced or null Hd1 expression under natural long days, as well as in single hd1 mutants in isogenic backgrounds. These data indicate that loss of repressor genes has been a key strategy to expand rice cultivation to Europe, and that Ehd1 is a central node integrating floral repressive signals.


Assuntos
Adaptação Fisiológica , Flores/fisiologia , Regulação da Expressão Gênica de Plantas , Oryza/fisiologia , Proteínas Repressoras/metabolismo , Alelos , Mapeamento Cromossômico , Meio Ambiente , Europa (Continente) , Flores/genética , Flores/efeitos da radiação , Genótipo , Oryza/genética , Oryza/efeitos da radiação , Fotoperíodo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Proteínas Repressoras/genética , Especificidade da Espécie
10.
Ann Bot ; 114(7): 1445-58, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24651369

RESUMO

BACKGROUND: Rice (Oryza sativa) and Arabidopsis thaliana have been widely used as model systems to understand how plants control flowering time in response to photoperiod and cold exposure. Extensive research has resulted in the isolation of several regulatory genes involved in flowering and for them to be organized into a molecular network responsive to environmental cues. When plants are exposed to favourable conditions, the network activates expression of florigenic proteins that are transported to the shoot apical meristem where they drive developmental reprogramming of a population of meristematic cells. Several regulatory factors are evolutionarily conserved between rice and arabidopsis. However, other pathways have evolved independently and confer specific characteristics to flowering responses. SCOPE: This review summarizes recent knowledge on the molecular mechanisms regulating daylength perception and flowering time control in arabidopsis and rice. Similarities and differences are discussed between the regulatory networks of the two species and they are compared with the regulatory networks of temperate cereals, which are evolutionarily more similar to rice but have evolved in regions where exposure to low temperatures is crucial to confer competence to flower. Finally, the role of flowering time genes in expansion of rice cultivation to Northern latitudes is discussed. CONCLUSIONS: Understanding the mechanisms involved in photoperiodic flowering and comparing the regulatory networks of dicots and monocots has revealed how plants respond to environmental cues and adapt to seasonal changes. The molecular architecture of such regulation shows striking similarities across diverse species. However, integration of specific pathways on a basal scheme is essential for adaptation to different environments. Artificial manipulation of flowering time by means of natural genetic resources is essential for expanding the cultivation of cereals across different environments.


Assuntos
Adaptação Fisiológica/genética , Arabidopsis/genética , Grão Comestível/genética , Flores/genética , Regulação da Expressão Gênica de Plantas , Oryza/genética , Proteínas de Plantas/genética , Arabidopsis/fisiologia , Arabidopsis/efeitos da radiação , Temperatura Baixa , Grão Comestível/fisiologia , Grão Comestível/efeitos da radiação , Flores/fisiologia , Flores/efeitos da radiação , Meristema/genética , Meristema/fisiologia , Meristema/efeitos da radiação , Oryza/fisiologia , Oryza/efeitos da radiação , Fotoperíodo , Proteínas de Plantas/metabolismo , Estações do Ano , Estresse Fisiológico/genética , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
11.
Theor Appl Genet ; 126(1): 101-8, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22968512

RESUMO

Altering root morphology of rice (Oryza sativa L.) cultivars could improve yields in drought-prone upland ecosystems. Marker-assisted backcross breeding was used to introgress four QTLs for root traits into an upland rice cultivar. The QTLs had previously been identified under experimental conditions in a different genetic background. The introgressed lines and the recurrent parent were grown for 6 years by resource-poor farmers in upland sites in Eastern India and yields recorded. In combination the QTLs significantly increased yield by 1 t ha(-1) under relatively favourable field conditions. In less favourable trials, the QTL effects were not detected due to greater heterogeneity in soil-water availability in very low yielding environments and consequent yield variability. Root studies under controlled conditions showed that lines with the introgressions had longer roots throughout tillering than the recurrent parent (14 cm longer 2 weeks after sowing). Therefore, both improved roots and increased yield can be attributed to the introgression of QTLs. This is the first demonstration that marker-assisted backcross breeding (MABC) to introgress multiple root QTLs identified under controlled conditions is an effective strategy to improve farmers' yields of upland rice. The strategy was used to breed a novel upland rice cultivar that has been released in India as Birsa Vikas Dhan 111.


Assuntos
Oryza/genética , Raízes de Plantas/genética , Locos de Características Quantitativas , Mapeamento Cromossômico , Cromossomos de Plantas , Produtos Agrícolas/genética , Cruzamentos Genéticos , Secas , Genes de Plantas , Marcadores Genéticos , Genótipo , Índia , Fenótipo , Solo , Água/metabolismo
12.
Biochemistry ; 51(25): 5083-90, 2012 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-22642810

RESUMO

Defects in the MMACHC gene represent the most common disorder of cobalamin (Cbl) metabolism, affecting synthesis of the enzyme cofactors adenosyl-Cbl and methyl-Cbl. The encoded MMACHC protein binds intracellular Cbl derivatives with different upper axial ligands and exhibits flavin mononucleotide (FMN)-dependent decyanase activity toward cyano-Cbl as well as glutathione (GSH)-dependent dealkylase activity toward alkyl-Cbls. We determined the structure of human MMACHC·adenosyl-Cbl complex, revealing a tailor-made nitroreductase scaffold which binds adenosyl-Cbl in a "base-off, five-coordinate" configuration for catalysis. We further identified an arginine-rich pocket close to the Cbl binding site responsible for GSH binding and dealkylation activity. Mutation of these highly conserved arginines, including a replication of the prevalent MMACHC missense mutation, Arg161Gln, disrupts GSH binding and dealkylation. We further showed that two Cbl-binding monomers dimerize to mediate the reciprocal exchange of a conserved "PNRRP" loop from both subunits, serving as a protein cap for the upper axial ligand in trans and required for proper dealkylation activity. Our dimeric structure is supported by solution studies, where dimerization is triggered upon binding its substrate adenosyl-Cbl or cofactor FMN. Together our data provide a structural framework to understanding catalytic function and disease mechanism for this multifunctional enzyme.


Assuntos
Arginina/química , Proteínas de Transporte/química , Complexos Multienzimáticos/química , Multimerização Proteica , Vitamina B 12/química , Vitamina B 12/fisiologia , Arginina/genética , Proteínas de Transporte/genética , Catálise , Cristalografia por Raios X , Humanos , Complexos Multienzimáticos/genética , Complexos Multienzimáticos/fisiologia , Mutação , Oxirredutases , Multimerização Proteica/genética , Processamento de Proteína Pós-Traducional/genética , Estrutura Terciária de Proteína/genética , Vitamina B 12/genética
13.
New Phytol ; 176(3): 665-672, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17822410

RESUMO

The root-knot nematode Meloidogyne graminicola is an obligate biotrophic parasite and a major pest of rice (Oryza sativa) for which resistant varieties are not currently available. Quantitative trait loci (QTLs) for partial resistance to M. graminicola were identified using a mapping population based on two rice varieties, Bala x Azucena. Experiments were carried out to investigate the interactions between M. graminicola and these two varieties in terms of nematode establishment, reproduction and effect on rice yield. Nematode establishment was also assessed in the mapping population. Meloidogyne graminicola consistently caused more galling and had higher reproductive success in Azucena than in Bala. M. graminicola did not significantly reduce yield in Bala, but caused a yield reduction of almost half in Azucena, suggesting that the partial resistance to nematode establishment was related to nematode tolerance. A total of six significant or putative QTLs for nematode tolerance were detected. For two of the QTLs detected, Azucena was the donor of the tolerance alleles, suggesting it may be possible to breed plants with greater tolerance than Bala.


Assuntos
Interações Hospedeiro-Parasita/genética , Oryza/genética , Raízes de Plantas/parasitologia , Locos de Características Quantitativas , Tylenchoidea/fisiologia , Animais , Mapeamento Cromossômico , Oryza/parasitologia , Oryza/fisiologia , Raízes de Plantas/fisiologia , Plantas Geneticamente Modificadas
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