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2.
bioRxiv ; 2024 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-38260543

RESUMO

The C4 photosynthetic pathway provided a major advantage to plants growing in hot, dry environments, including the ancestors of our most productive crops. Two traits were essential for the evolution of this pathway: increased vein density and the functionalization of bundle sheath cells for photosynthesis. Although GRAS transcriptional regulators, including SHORT ROOT (SHR), have been implicated in mediating leaf patterning in both C3 and C4 species, little is known about what controls the specialized features of the cells that mediate C4 metabolism and physiology. We show in the model monocot, Setaria viridis, that SHR regulates components of multiple cell identities, including chloroplast biogenesis and photosynthetic gene expression in bundle sheath cells, a central feature of C4 plants. Furthermore, we found that it also contributes to the two-cell compartmentalization of the characteristic four-carbon shuttle pathway. Disruption of SHR function clearly reduced photosynthetic capacity and seed yield in mutant plants under heat stress. Together, these results show how cell identities are remodeled by SHR to host the suite of traits characteristic of C4 regulation, which are a main engineering target in non-C4 crops to improve climate resilience.

3.
Hematol., Transfus. Cell Ther. (Impr.) ; 44(3): 314-320, July-Sept. 2022. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1405014

RESUMO

ABSTRACT Background: The date of acute lymphoblastic leukemia (ALL) diagnosis has been studied regarding potential etiologic roles with contrasting results and the issue remains controversial. The principal aim of this study was to analyze monthly variation of ALL diagnosis in a large homogenous Hispanic Latin American cohort over 15 years; its association with survival rates was also assessed. Methods: Clinical files and electronic records of 501 consecutive patients of all ages with ALL in northeastern Mexico over the years of 2004-2018 were scrutinized. Patients were divided into children <18 and adults >18 years. The Chi-square heterogeneity analysis was used to test for non-uniform variation. The Poisson regression analysis was used to fit sinusoidal (harmonic) models to the data, using the month of diagnosis as a covariate in a separate model. Results: During the study period 363 children (72.5%) and 138 adults (27.5%) (p < 0.001) were diagnosed with ALL. Heterogeneity across the months of diagnosis was confirmed (p = 0.019) and the Poisson regression analysis confirmed a significant monthly variation (p < 0.001) (95% CI, 3.024-3.745), a higher annual peak being observed in the month of March (p = 0.002), followed by a second peak in October (p = 0.026). The five-year OS for children was 68.2% (95% CI, 67.64-68.74) and for adults, 43.7% (95% CI, 42.67-44.71) (p < 0.001). No significant association between the month of diagnosis and OS was found (p = 0.789). Conclusion: The monthly variation of ALL diagnosis was documented; these results confirm the heterogeneous behavior of the disease and appear to be consistent with an interplay of environmental and biologic factors. Further studies are needed to examine putative candidate agents.


Assuntos
Humanos , Masculino , Feminino , Recém-Nascido , Lactente , Pré-Escolar , Criança , Adolescente , Adulto , Pessoa de Meia-Idade , Idoso , Idoso de 80 Anos ou mais , Leucemia-Linfoma Linfoblástico de Células Precursoras
4.
Dev Cell ; 57(4): 451-465.e6, 2022 02 28.
Artigo em Inglês | MEDLINE | ID: mdl-35148835

RESUMO

Wounding is a trigger for both regeneration and defense in plants, but it is not clear whether the two responses are linked by common activation or regulated as trade-offs. Although plant glutamate-receptor-like proteins (GLRs) are known to mediate defense responses, here, we implicate GLRs in regeneration through dynamic changes in chromatin and transcription in reprogramming cells near wound sites. We show that genetic and pharmacological inhibition of GLR activity increases regeneration efficiency in multiple organ repair systems in Arabidopsis and maize. We show that the GLRs work through salicylic acid (SA) signaling in their effects on regeneration, and mutants in the SA receptor NPR1 are hyper-regenerative and partially resistant to GLR perturbation. These findings reveal a conserved mechanism that regulates a trade-off between defense and regeneration, and they also offer a strategy to improve regeneration in agriculture and conservation.


Assuntos
Regulação da Expressão Gênica de Plantas/genética , Receptores de Glutamato/metabolismo , Regeneração/fisiologia , Arabidopsis/metabolismo , Proteínas de Arabidopsis/metabolismo , Cromatina/metabolismo , Plantas/metabolismo , Receptores de Glutamato/genética , Transdução de Sinais/fisiologia
5.
Hematol Transfus Cell Ther ; 44(3): 314-320, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-33422491

RESUMO

BACKGROUND: The date of acute lymphoblastic leukemia (ALL) diagnosis has been studied regarding potential etiologic roles with contrasting results and the issue remains controversial. The principal aim of this study was to analyze monthly variation of ALL diagnosis in a large homogenous Hispanic Latin American cohort over 15 years; its association with survival rates was also assessed. METHODS: Clinical files and electronic records of 501 consecutive patients of all ages with ALL in northeastern Mexico over the years of 2004-2018 were scrutinized. Patients were divided into children ≤18 and adults >18 years. The Chi-square heterogeneity analysis was used to test for non-uniform variation. The Poisson regression analysis was used to fit sinusoidal (harmonic) models to the data, using the month of diagnosis as a covariate in a separate model. RESULTS: During the study period 363 children (72.5%) and 138 adults (27.5%) (p < 0.001) were diagnosed with ALL. Heterogeneity across the months of diagnosis was confirmed (p = 0.019) and the Poisson regression analysis confirmed a significant monthly variation (p < 0.001) (95% CI, 3.024-3.745), a higher annual peak being observed in the month of March (p = 0.002), followed by a second peak in October (p = 0.026). The five-year OS for children was 68.2% (95% CI, 67.64-68.74) and for adults, 43.7% (95% CI, 42.67-44.71) (p < 0.001). No significant association between the month of diagnosis and OS was found (p = 0.789). CONCLUSION: The monthly variation of ALL diagnosis was documented; these results confirm the heterogeneous behavior of the disease and appear to be consistent with an interplay of environmental and biologic factors. Further studies are needed to examine putative candidate agents.

7.
Front Plant Sci ; 12: 745861, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34659316

RESUMO

Roots have a fundamental role in plant growth and adaptation to different environments. Diversity in root morphology and architecture enables plants to acquire water and nutrients in contrasting substrate conditions, resist biotic and abiotic stress, and develop symbiotic associations. At its most fundamental level, morphology is determined by discrete changes in tissue patterning. Differences in the number and arrangement of the cell layers in the root can change tissue structure, as well as root length and girth, affecting important productivity traits. Therefore, understanding the molecular mechanisms controlling variation in developmental patterning is an important goal in biology. The ground tissue (GT) system is an ideal model to study the genetic basis of morphological diversity because it displays great interspecific variability in cell layer number. In addition, the genetic circuit controlling GT patterning in Arabidopsis thaliana has been well described, although little is known about species with more complex root anatomies. In this review, we will describe the Arabidopsis model for root radial patterning and present recent progress in elucidating the genetic circuitry controlling GT patterning in monocots and the legume Medicago truncatula (Mt), species that develop roots with more complex anatomies and multilayered cortex.

10.
Transpl Immunol ; 67: 101412, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34020046

RESUMO

Polyneuropathy, organomegaly, endocrinopathy, monoclonal gammopathy, and skin changes (POEMS) syndrome is a multisystem autoinflammatory disease due to an underlying plasma cell disorder that lacks a standard treatment strategy because of its rarity. We report a case of relapsed POEMS syndrome successfully treated with a second ambulatory autologous hematopoietic-cell transplantation (AHCT) after a daratumumab desensitization protocol performed during the coronavirus disease (COVID-19) pandemic in a patient with coexisting human immunodeficiency virus (HIV), hepatitis B virus (HBV) and syphilis infections. He is a 37-year old Latin-American male who had been treated with radiation, CyBorD regimen, AHCT and bortezomib therapy before being referred to our service. It was decided to administer daratumumab therapy and subsequently perform the transplant. Placement of central venous access, fluid infusion, conditioning regimen with melphalan and previously cryopreserved autograft infusion were carried out in an outpatient basis. Following second AHCT, the patient demonstrated clinical, VEGF, hematological response and remains SARS-CoV-2 infection-free and in POEMS remission with excellent quality-of-life at last follow up (6 months). We evidenced that thanks to an outpatient transplant program, the best therapeutic modalities can be offered to patients with hematologic malignancies in the context of present or future pandemics. Finally, high-complexity patients with HIV infection should have access to the same treatment strategies as non-infected patients. A second AHCT in the outpatient setting is feasible, safe and highly effective to treat patients with relapsed POEMS syndrome.


Assuntos
Infecções por HIV/complicações , Transplante de Células-Tronco Hematopoéticas , Hepatite B Crônica/complicações , Síndrome POEMS/cirurgia , Sífilis/complicações , Adulto , Anticorpos Monoclonais/uso terapêutico , Antineoplásicos/uso terapêutico , Bortezomib/uso terapêutico , COVID-19/epidemiologia , Humanos , Hospedeiro Imunocomprometido , Masculino , SARS-CoV-2 , Transplante Autólogo , Resultado do Tratamento
11.
Clin Transplant ; 35(5): e14247, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33559181

RESUMO

Transfusion has a recognized immunomodulatory effect, and its role on the outcomes after an ambulatory autologous hematopoietic stem cell transplantation (auto-HSCT) following reduced intensity conditioning (RIC) has not been documented. A study to assess factors associated with the number of packed red blood cells (PRBCs) and platelet units transfused and their impact on survival rates of auto-HSCT recipients after RIC was conducted between 2013 and 2019. Transfusions were recorded from days 0 to 100. Of the 130 patients studied, seventy (53.9%) required transfusion support. The median number of PRBC transfused was 2 (range 1-20), and for platelets, it was also 2 units (range 1-19). Infused CD34 + cells/kg, pre-transplant CMV status, and relapse/progression were significantly associated with the number of PRBC units transfused and sex, infused CD34 + cells/kg, and pre-transplant CMV status with the number of platelet units transfused. In multivariate analysis, a high/very high Disease Risk Index (P = .001) (P = .001) and transfusion of ≥ 5 total blood products (P = .001) (P = .010) were associated with decreased disease-free and overall survival. Two-year cumulative incidence of relapse was 50% for transfused patients vs. 34% for those not transfused (P = .009). These data suggest that the transfusion burden and its interplay with other patient and transplant-related factors could be associated with inferior auto-HSCT outcomes.


Assuntos
Neoplasias Hematológicas , Transplante de Células-Tronco Hematopoéticas , Transfusão de Sangue , Humanos , Recidiva Local de Neoplasia , Pacientes Ambulatoriais , Estudos Retrospectivos , Condicionamento Pré-Transplante , Transplante Autólogo
12.
Leuk Lymphoma ; 62(7): 1619-1628, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33491518

RESUMO

Autologous stem cell transplantation (ASCT) is commonly an in-patient procedure. However, outpatient ASCT grows as a cost-effective and feasible option for patients with lymphoma and reports assessing it after reduced-intensity conditioning (RIC) are sparse. We report the outcome of 102 patients with lymphoma who underwent ASCT on a full outpatient basis in a single-center transplant program between 2010 and 2020. Forty-two percent of the cohort required transfusion support, 36.3% experienced a neutropenic fever episode, 25.5% mucositis, and 9.8% developed severe infection. At a median time of 5 days (range 1-28), only 22.5% of the cohort required admission within the first 100 days after the autograft, median length of hospital stay was 0 days (range 0-14) and neutropenic fever was the most common reason for hospitalization. Non-relapse mortality at 1 year was 5%. ASCT in a completely outpatient setting is feasible, safe, and highly effective to treat lymphoma patients.


Assuntos
Transplante de Células-Tronco Hematopoéticas , Linfoma , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Humanos , Linfoma/terapia , Pacientes Ambulatoriais , Transplante de Células-Tronco/efeitos adversos , Condicionamento Pré-Transplante , Transplante Autólogo
13.
Blood Cells Mol Dis ; 88: 102537, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33493823

RESUMO

OBJECTIVES: Ambulatory allogeneic hematopoietic cell transplantation (allo-HCT) after reduced-intensity conditioning (RIC) is a cost-effective option for hematology patients. Data on the impact of transfusion burden in this setting are scarce; we analyzed this retrospectively. METHODS: A study of 177 HLA-identical and haploidentical allo-HCT recipients on an outpatient basis was conducted between 2013 and 2019. Packed red blood cell (PRBC) and platelet transfusions were documented from days 0-100 after HCT. RESULTS: A total of 121 patients (68.4%) required transfusion while 56 (31.6%) did not. In the multivariate analysis, a lower disease-free (DFS) and overall survival (OS) were documented for patients that received ≥9 total blood products (p = 0.018) (p = 0.014), those who required hospitalization (p = 0.001) (p < 0.001), had acute graft-versus-host disease (p = 0.016) (p = 0.004), and a high/very high Disease-Risk-Index (p = 0.002; p = 0.004), respectively. Transfusion of ≥5 PRBC units was associated with a lower OS (p = 0.027). The cumulative incidence of transplant-related mortality at two years for an HLA-identical transplant was 9.5% and for haploidentical, it was 27.1% (p = 0.027); this last group had significantly more transfusion demands than HLA-identical recipients (p = 0.029). CONCLUSION: Increased blood product utilization is an independent predictor of decreased survival in ambulatory RIC allo-HCT recipients. Further evidence leading to individualized guidelines to transfuse in this complex scenario is needed.


Assuntos
Transfusão de Eritrócitos , Transplante de Células-Tronco Hematopoéticas , Transfusão de Plaquetas , Condicionamento Pré-Transplante , Adolescente , Adulto , Idoso , Feminino , Doença Enxerto-Hospedeiro/etiologia , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Transplante de Células-Tronco Hematopoéticas/métodos , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Análise de Sobrevida , Condicionamento Pré-Transplante/efeitos adversos , Condicionamento Pré-Transplante/métodos , Transplante Homólogo/efeitos adversos , Transplante Homólogo/métodos , Adulto Jovem
14.
Nature ; 549(7670): 91-95, 2017 09 07.
Artigo em Inglês | MEDLINE | ID: mdl-28737761

RESUMO

Glutamate receptors are well characterized channels that mediate cell-to-cell communication during neurotransmission in animals, but their functional role in organisms without a nervous system remains unclear. In plants, genes of the GLUTAMATE RECEPTOR-LIKE (GLR) family have been implicated in defence against pathogens, reproduction, control of stomata aperture and light signal transduction. However, the large number of GLR genes present in angiosperm genomes (20 to 70) has prevented the observation of strong phenotypes in loss-of-function mutants. Here we show that in the basal land plant Physcomitrella patens, mutation of the GLR genes GLR1 and GLR2 causes failure of sperm cells to target the female reproductive organs. In addition, we show that GLR genes encode non-selective Ca2+-permeable channels that can regulate cytoplasmic Ca2+ and are needed to induce the expression of a BELL1-like transcription factor essential for zygote development. Our work reveals functions for GLR channels in sperm chemotaxis and transcriptional regulation. Sperm chemotaxis is essential for fertilization in both animals and early land plants such as bryophytes and pteridophytes. Therefore, our results suggest that ionotropic glutamate receptors may have been conserved throughout plant evolution to mediate cell-to-cell communication during sexual reproduction.


Assuntos
Bryopsida/metabolismo , Quimiotaxia , Receptores Ionotrópicos de Glutamato/metabolismo , Bryopsida/embriologia , Bryopsida/genética , Cálcio/metabolismo , Comunicação Celular/genética , Quimiotaxia/genética , Regulação da Expressão Gênica , Genes Essenciais , Mutação , Receptores Ionotrópicos de Glutamato/genética , Reprodução/genética , Fatores de Transcrição/metabolismo , Transcrição Gênica , Zigoto/metabolismo
15.
Plant J ; 90(3): 447-465, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28161902

RESUMO

Molecular evolutionary studies correlate genomic and phylogenetic information with the emergence of new traits of organisms. These traits are, however, the consequence of dynamic gene networks composed of functional modules, which might not be captured by genomic analyses. Here, we established a method that combines large-scale genomic and phylogenetic data with gene co-expression networks to extensively study the evolutionary make-up of modules in the moss Physcomitrella patens, and in the angiosperms Arabidopsis thaliana and Oryza sativa (rice). We first show that younger genes are less annotated than older genes. By mapping genomic data onto the co-expression networks, we found that genes from the same evolutionary period tend to be connected, whereas old and young genes tend to be disconnected. Consequently, the analysis revealed modules that emerged at a specific time in plant evolution. To uncover the evolutionary relationships of the modules that are conserved across the plant kingdom, we added phylogenetic information that revealed duplication and speciation events on the module level. This combined analysis revealed an independent duplication of cell wall modules in bryophytes and angiosperms, suggesting a parallel evolution of cell wall pathways in land plants. We provide an online tool allowing plant researchers to perform these analyses at http://www.gene2function.de.


Assuntos
Proteínas de Plantas/metabolismo , Arabidopsis/genética , Arabidopsis/metabolismo , Bryopsida/genética , Bryopsida/metabolismo , Evolução Molecular , Oryza/genética , Oryza/metabolismo , Filogenia , Proteínas de Plantas/genética
16.
Mol Plant ; 9(2): 205-220, 2016 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-26687813

RESUMO

Identifying the genetic mechanisms that underpin the evolution of new organ and tissue systems is an aim of evolutionary developmental biology. Comparative functional genetic studies between angiosperms and bryophytes can define those genetic changes that were responsible for developmental innovations. Here, we report the generation of a transcriptome atlas covering most phases in the life cycle of the model bryophyte Physcomitrella patens, including detailed sporophyte developmental progression. We identified a comprehensive set of sporophyte-specific transcription factors, and found that many of these genes have homologs in angiosperms that function in developmental processes such as flowering and shoot branching. Deletion of the PpTCP5 transcription factor results in development of supernumerary sporangia attached to a single seta, suggesting that it negatively regulates branching in the moss sporophyte. Given that TCP genes repress branching in angiosperms, we suggest that this activity is ancient. Finally, comparison of P. patens and Arabidopsis thaliana transcriptomes led us to the identification of a conserved core of transcription factors expressed in tip-growing cells. We identified modifications in the expression patterns of these genes that could account for developmental differences between P. patens tip-growing cells and A. thaliana pollen tubes and root hairs.


Assuntos
Bryopsida/genética , Proteínas de Plantas/genética , Transcriptoma , Bryopsida/classificação , Bryopsida/metabolismo , Evolução Molecular , Regulação da Expressão Gênica de Plantas , Proteínas de Plantas/metabolismo
17.
Plant Cell ; 21(12): 4044-58, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-20028841

RESUMO

To examine the role of the tonoplast in plant salt tolerance and identify proteins involved in the regulation of transporters for vacuolar Na(+) sequestration, we exploited a targeted quantitative proteomics approach. Two-dimensional differential in-gel electrophoresis analysis of free flow zonal electrophoresis separated tonoplast fractions from control, and salt-treated Mesembryanthemum crystallinum plants revealed the membrane association of glycolytic enzymes aldolase and enolase, along with subunits of the vacuolar H(+)-ATPase V-ATPase. Protein blot analysis confirmed coordinated salt regulation of these proteins, and chaotrope treatment indicated a strong tonoplast association. Reciprocal coimmunoprecipitation studies revealed that the glycolytic enzymes interacted with the V-ATPase subunit B VHA-B, and aldolase was shown to stimulate V-ATPase activity in vitro by increasing the affinity for ATP. To investigate a physiological role for this association, the Arabidopsis thaliana cytoplasmic enolase mutant, los2, was characterized. These plants were salt sensitive, and there was a specific reduction in enolase abundance in the tonoplast from salt-treated plants. Moreover, tonoplast isolated from mutant plants showed an impaired ability for aldolase stimulation of V-ATPase hydrolytic activity. The association of glycolytic proteins with the tonoplast may not only channel ATP to the V-ATPase, but also directly upregulate H(+)-pump activity.


Assuntos
Frutose-Bifosfato Aldolase/metabolismo , Mesembryanthemum/genética , Fosfopiruvato Hidratase/metabolismo , Proteoma/metabolismo , Plantas Tolerantes a Sal/genética , ATPases Vacuolares Próton-Translocadoras/metabolismo , Arabidopsis/enzimologia , Arabidopsis/genética , Eletroforese em Gel Bidimensional , Frutose-Bifosfato Aldolase/genética , Regulação da Expressão Gênica de Plantas , Mesembryanthemum/enzimologia , Microssomos , Fosfopiruvato Hidratase/genética , Proteômica , Plantas Tolerantes a Sal/enzimologia , Cloreto de Sódio/metabolismo , Espectrometria de Massas por Ionização por Electrospray , ATPases Vacuolares Próton-Translocadoras/genética , Vacúolos/metabolismo
18.
Fish Shellfish Immunol ; 23(4): 760-9, 2007 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17478099

RESUMO

The LC(50) of the organophosphorus pesticides (OPs) diazinon to Nile tilapia (Oreochromis niloticus) was determined, thereafter, hepatic activity, phagocytic index, percentages of active cells, relative spleen weight, total IgM concentration and lymphoproliferation rates were compared between diazinon exposed groups (LC(50) and (1/2)LC(50)) and non-exposed control group. Experimental data show that diazinon is highly toxic for juvenile Nile tilapia (LC(50)=7.830 ppm) and presents immunotoxic properties which affect both the innate and cellular adaptive immune responses of this fish, as revealed by the fact that splenocyte proliferation and phagocytic indices were significantly decreased after acute exposure to the pesticide. However, the hepatic biochemical parameters and the total circulating IgM concentrations were not affected in this experimental model.


Assuntos
Ciclídeos/imunologia , Ciclídeos/fisiologia , Diazinon/toxicidade , Sistema Imunitário/efeitos dos fármacos , Fígado/efeitos dos fármacos , Poluentes Químicos da Água/toxicidade , Animais , Proliferação de Células/efeitos dos fármacos , Enzimas/sangue , Enzimas/efeitos dos fármacos , Imunoglobulina M/sangue , Dose Letal Mediana , Tamanho do Órgão/efeitos dos fármacos , Fagocitose/efeitos dos fármacos , Baço/citologia , Baço/efeitos dos fármacos
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