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1.
Heliyon ; 10(9): e30884, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38774091

RESUMO

The demand for dietary fiber-rich cookies has increased due to customer awareness about the importance of dietary fiber in human health. In addition, the urge of creating food sustainability has led to the need to reuse food by-products. In this study, dietary fiber-rich cookies were developed by incorporating jackfruit rind (JFR) powder, a by-product of jackfruit processing, as a replacement for wheat flour. The study aimed to evaluate the effects of different replacement levels (0, 10, 20, 30 and 40 %) on the proximate composition, physical properties and overall sensory acceptability of the cookies. While JFR powder addition led to a significant increase in dietary fiber and antioxidant (phenolics, flavonoids and carotenoids) contents of the cookies, the physical properties and overall acceptability of the cookies were adversely affected. The total dietary fiber and total phenolic content of the cookies at 40 % JFR powder addition were 5 and 5.5 times as much as those of the cookies with 0 % JFR powder addition. To address the adverse effects of JFR addition, various concentrations of ascorbic acid (AA), a dough improver agent, were added to the blended dough, and their effects on dough and cookie properties were investigated. With the addition of ascorbic acid at concentrations of 200 mg ascorbic acid per 100 g of the blend flour, the cookie density and cookie hardness reduced by 16 % and 31 %, respectively while the overall acceptability increased by 37 % compared to those of the cookies without ascorbic acid addition.

2.
Front Plant Sci ; 9: 771, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29937771

RESUMO

Pierce's disease is a major threat to grapevines caused by the bacterium Xylella fastidiosa. Although devoid of a type 3 secretion system commonly employed by bacterial pathogens to deliver effectors inside host cells, this pathogen is able to influence host parenchymal cells from the xylem lumen by secreting a battery of hydrolytic enzymes. Defining the cellular and biochemical changes induced during disease can foster the development of novel therapeutic strategies aimed at reducing the pathogen fitness and increasing plant health. To this end, we investigated the transcriptional, proteomic, and metabolomic responses of diseased Vitis vinifera compared to healthy plants. We found that several antioxidant strategies were induced, including the accumulation of gamma-aminobutyric acid (GABA) and polyamine metabolism, as well as iron and copper chelation, but these were insufficient to protect the plant from chronic oxidative stress and disease symptom development. Notable upregulation of phytoalexins, pathogenesis-related proteins, and various aromatic acid metabolites was part of the host responses observed. Moreover, upregulation of various cell wall modification enzymes followed the proliferation of the pathogen within xylem vessels, consistent with the intensive thickening of vessels' secondary walls observed by magnetic resonance imaging. By interpreting the molecular profile changes taking place in symptomatic tissues, we report a set of molecular markers that can be further explored to aid in disease detection, breeding for resistance, and developing therapeutics.

3.
BMC Infect Dis ; 18(1): 186, 2018 04 18.
Artigo em Inglês | MEDLINE | ID: mdl-29669531

RESUMO

BACKGROUND: GSK has modified the licensed monovalent bulk manufacturing process for its split-virion inactivated quadrivalent influenza vaccine (IIV4) to harmonize the process among different strains, resulting in an increased number of finished vaccine doses, while compensating for the change from inactivated trivalent influenza vaccine (IIV3) to IIV4. To confirm the manufacturing changes do not alter the profile of the vaccine, a clinical trial was conducted to compare IIV4 made by the currently licensed process with a vaccine made by the new (investigational) process (IIV4-I). The main objectives were to compare the reactogenicity and safety of IIV4-I versus IIV4 in all age groups, and to demonstrate the non-inferiority of the hemagglutination-inhibition (HI) antibody responses based on the geometric mean titer ratio of IIV4-I versus IIV4 in children. METHODS: The Phase III, randomized, double-blind, multinational study included three cohorts: adults (18-49 years; N = 120), children (3-17 years; N = 821), and infants (6-35 months; N = 940). Eligible subjects in each cohort were randomized 1:1 to receive IIV4-I or IIV4. Both vaccines contained 15 µg of hemagglutinin antigen for each of the four seasonal virus strains. Adults and vaccine-primed children received one dose of vaccine, and vaccine-unprimed children received two doses of vaccine 28 days apart. All children aged ≥9 years were considered to be vaccine-primed and received one dose of vaccine. RESULTS: The primary immunogenicity objective of the study was met in demonstrating immunogenic non-inferiority of IIV4-I versus IIV4 in children. The IIV4-I was immunogenic against all four vaccine strains in each age cohort. The reactogenicity and safety profile of IIV4-I was similar to IIV4 in each age cohort, and there was no increase in the relative risk of fever (≥38 °C) with IIV4-I versus IIV4 within the 7-day post-vaccination period in infants (1.06; 95% Confidence Interval: 0.75, 1.50; p = 0.786). CONCLUSIONS: The study demonstrated that in adults, children, and infants, the IIV4-I made using an investigational manufacturing process was immunogenic with a reactogenicity and safety profile that was similar to licensed IIV4. These results support that the investigational process used to manufacture IIV4-I is suitable to replace the current licensed process. TRIAL REGISTRATION: ClinicalTrials.gov: NCT02207413 ; trial registration date: August 4, 2014.


Assuntos
Vacinas contra Influenza/efeitos adversos , Vacinas contra Influenza/imunologia , Vacinas de Produtos Inativados/efeitos adversos , Vacinas de Produtos Inativados/imunologia , Adolescente , Adulto , Criança , Pré-Escolar , Estudos de Coortes , Método Duplo-Cego , Feminino , Febre/etiologia , Testes de Inibição da Hemaglutinação , Humanos , Lactente , Vacinas contra Influenza/uso terapêutico , Influenza Humana/prevenção & controle , Masculino , Pessoa de Meia-Idade , Vacinas de Produtos Inativados/uso terapêutico
4.
Int J Mol Sci ; 18(1)2017 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-28054967

RESUMO

Anthrax toxin receptor-mediated drug development for blocking anthrax toxin action has received much attention in recent decades. In this study, we produced a secreted anthrax decoy fusion protein comprised of a portion of the human capillary morphogenesis gene-2 (CMG2) protein fused via a linker to the fragment crystallizable (Fc) domain of human immunoglobulin G1 in Nicotiana benthamiana plants using a transient expression system. Using the Cauliflower Mosaic Virus (CaMV) 35S promoter and co-expression with the p19 gene silencing suppressor, we were able to achieve a high level of recombinant CMG2-Fc-Apo (rCMG2-Fc-Apo) protein accumulation. Production kinetics were observed up to eight days post-infiltration, and maximum production of 826 mg/kg fresh leaf weight was observed on day six. Protein A affinity chromatography purification of the rCMG2-Fc-Apo protein from whole leaf extract and apoplast wash fluid showed the homodimeric form under non-reducing gel electrophoresis and mass spectrometry analysis confirmed the molecular integrity of the secreted protein. The N-glycosylation pattern of purified rCMG2-Fc-Apo protein was analysed; the major portion of N-glycans consists of complex type structures in both protein samples. The most abundant (>50%) N-glycan structure was GlcNAc2(Xyl)Man3(Fuc)GlcNAc2 in rCMG2-Fc-Apo recovered from whole leaf extract and apoplast wash fluid. High mannose N-glycan structures were not detected in the apoplast wash fluid preparation, which confirmed the protein secretion. Altogether, these findings demonstrate that high-level production of rCMG2-Fc-Apo can be achieved by transient production in Nicotiana benthamiana plants with apoplast targeting.


Assuntos
Imunoglobulina G/genética , Nicotiana/genética , Plantas Geneticamente Modificadas/genética , Receptores de Peptídeos/genética , Sequência de Aminoácidos , Antraz/metabolismo , Antraz/microbiologia , Bacillus anthracis/metabolismo , Biotecnologia , Caulimovirus/genética , Clonagem Molecular , Descoberta de Drogas , Glicosilação , Humanos , Imunoglobulina G/química , Imunoglobulina G/metabolismo , Regiões Promotoras Genéticas , Receptores de Peptídeos/química , Receptores de Peptídeos/metabolismo , Proteínas Recombinantes de Fusão/química , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/metabolismo
5.
Front Plant Sci ; 7: 743, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27379103

RESUMO

To optimize the expression, extraction and purification of plant-derived tetrameric recombinant human butyrylcholinesterase (prBChE), we describe the development and use of plant viral amplicon-based gene expression system; Tobacco Mosaic Virus (TMV) RNA-based overexpression vector (TRBO) to express enzymatically active FLAG-tagged plant made recombinant butyrylcholinesterase (rBChE) in Nicotiana benthamiana leaves using transient agroinfiltration. Two gene expression cassettes were designed to express the recombinant protein in either the ER or to the apoplastic compartment. Leaf homogenization was used to isolate ER-retained recombinant butyrylcholinesterase (prBChE-ER) while apoplast-targeted rBChE was isolated by either leaf homogenization (prBChE) or vacuum-extraction of apoplastic wash fluid (prBChE-AWF). rBChE from apoplast wash fluid had a higher specific activity but lower enzyme yield than leaf homogenate. To optimize the isolation and purification of total recombinant protein from leaf homogenates, an acidic extraction buffer was used. The acidic extraction buffer yielded >95% enzymatically active tetrameric rBChE as verified by Coomassie stained and native gel electrophoresis. Furthermore, when compared to human butyrylcholinesterase, the prBChE was found to be similar in terms of tetramerization and enzyme kinetics. The N-linked glycan profile of purified prBChE-ER was found to be mostly high mannose structures while the N-linked glycans on prBChE-AWF were primarily complex. The glycan profile of the prBChE leaf homogenates showed a mixture of high mannose, complex and paucimannose type N-glycans. These findings demonstrate the ability of plants to produce rBChE that is enzymatically active and whose oligomeric state is comparable to mammalian butyrylcholinesterase. The process of plant made rBChE tetramerization and strategies for improving its pharmacokinetics properties are also discussed.

6.
PLoS One ; 11(7): e0159610, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27459099

RESUMO

Huanglongbing (HLB; citrus greening) is the most devastating disease of citrus worldwide. No cure is yet available for this disease and infected trees generally decline after several months. Disease management depends on early detection of symptoms and chemical control of insect vectors. In this work, different combinations of organic compounds were tested for the ability to modulate citrus molecular responses to HLB disease beneficially. Three small-molecule regulating compounds were tested: 1) L-arginine, 2) 6-benzyl-adenine combined with gibberellins, and 3) sucrose combined with atrazine. Each treatment contained K-phite mineral solution and was tested at two different concentrations. Two trials were conducted: one in the greenhouse and the other in the orchard. In the greenhouse study, responses of 42 key genes involved in sugar and starch metabolism, hormone-related pathways, biotic stress responses, and secondary metabolism in treated and untreated mature leaves were analyzed. TGA5 was significantly induced by arginine. Benzyladenine and gibberellins enhanced two important genes involved in biotic stress responses: WRKY54 and WRKY59. Sucrose combined with atrazine mainly upregulated key genes involved in carbohydrate metabolism such as sucrose-phosphate synthase, sucrose synthase, starch synthase, and α-amylase. Atrazine also affected expression of some key genes involved in systemic acquired resistance such as EDS1, TGA6, WRKY33, and MYC2. Several treatments upregulated HSP82, which might help protect protein folding and integrity. A subset of key genes was chosen as biomarkers for molecular responses to treatments under field conditions. GPT2 was downregulated by all small-molecule treatments. Arginine-induced genes involved in systemic acquired resistance included PR1, WRKY70, and EDS1. These molecular data encourage long-term application of treatments that combine these regulating molecules in field trials.


Assuntos
Citrus/genética , Interações Hospedeiro-Patógeno/genética , Doenças das Plantas/genética , Arginina/farmacologia , Atrazina/farmacologia , Metabolismo dos Carboidratos/genética , Citrus/efeitos dos fármacos , Citrus/metabolismo , Citrus/microbiologia , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Imunidade Inata/genética , Fenótipo , Doenças das Plantas/microbiologia , Metabolismo Secundário/genética , Estresse Fisiológico/genética , Sacarose/farmacologia
7.
Biotechnol Prog ; 30(4): 905-15, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25180328

RESUMO

For biofuel applications, synthetic endoglucanase E1 and xylanase (Xyn10A) derived from Acidothermus cellulolyticus were transiently expressed in detached whole sunflower (Helianthus annuus L.) leaves using vacuum infiltration. Three different expression systems were tested, including the constitutive CaMV 35S-driven, CMVar (Cucumber mosaic virus advanced replicating), and TRBO (Tobacco mosaic virus RNA-Based Overexpression Vector) systems. For 6-day leaf incubations, codon-optimized E1 and xylanase driven by the CaMV 35S promoter were successfully expressed in sunflower leaves. The two viral expression vectors, CMVar and TRBO, were not successful although we found high expression in Nicotiana benthamiana leaves previously for other recombinant proteins. To further enhance transient expression, we demonstrated two novel methods: using the plant hormone methyl jasmonic acid in the agroinfiltration buffer and two-phase optimization of the leaf incubation temperature. When methyl jasmonic acid was added to Agrobacterium tumefaciens cell suspensions and infiltrated into plant leaves, the functional enzyme production increased 4.6-fold. Production also increased up to 4.2-fold when the leaf incubation temperature was elevated above the typical temperature, 20C, to 30C in the late incubation phase, presumably due to enhanced rate of protein synthesis in plant cells. Finally, we demonstrated co-expression of E1 and xylanase in detached sunflower leaves. To our knowledge, this is the first report of (co)expression of heterologous plant cell wall-degrading enzymes in sunflower.


Assuntos
Agrobacterium tumefaciens/metabolismo , Biocombustíveis , Celulase/genética , Endo-1,4-beta-Xilanases/genética , Agrobacterium tumefaciens/genética , Celulase/biossíntese , Endo-1,4-beta-Xilanases/biossíntese , Regulação da Expressão Gênica de Plantas , Helianthus/enzimologia , Helianthus/genética , Células Vegetais/enzimologia , Células Vegetais/metabolismo , Folhas de Planta/enzimologia , Plantas Geneticamente Modificadas/química , Regiões Promotoras Genéticas
8.
Plant Sci ; 217-218: 87-98, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24467900

RESUMO

A systems-level analysis reveals details of molecular mechanisms underlying puffing disorder in Citrus fruit. Flavedo, albedo and juice sac tissues of normal fruits and fruits displaying symptoms of puffing disorder were studied using metabolomics at three developmental stages. Microarrays were used to compare normal and puffed fruits for each of the three tissues. A protein-protein interaction network inferred from previous work on Arabidopsis identified hub proteins whose transcripts show significant changes in expression. Glycolysis, the backbone of primary metabolism, appeared to be severely affected by the disorder, based on both transcriptomic and metabolomic results. Significantly less citric acid was observed consistently in puffed fruits. Gene set enrichment analysis suggested that glycolysis and carbohydrate metabolism were significantly altered in puffed samples in both albedo and flavedo. Expression of invertases and genes for sucrose export, amylose-starch and starch-maltose conversion was higher in puffed fruits. These changes may significantly alter source-sink communications. Genes associated with gibberellin and cytokinin signaling were downregulated in symptomatic albedo tissues, suggesting that these hormones play key roles in the disorder. Findings may be applied toward the development of early diagnostic methods based on host response genes and metabolites (i.e. citric acid), and toward therapeutics based on hormones.


Assuntos
Citrus/genética , Citrus/metabolismo , Frutas/metabolismo , Perfilação da Expressão Gênica , Metabolômica/métodos , Análise de Sequência com Séries de Oligonucleotídeos , Doenças das Plantas , Reguladores de Crescimento de Plantas/genética , Reguladores de Crescimento de Plantas/metabolismo , Mapas de Interação de Proteínas , Transdução de Sinais , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
9.
Plant Physiol ; 164(3): 1191-203, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24449710

RESUMO

The enzyme polyphenol oxidase (PPO) catalyzes the oxidation of phenolic compounds into highly reactive quinones. Polymerization of PPO-derived quinones causes the postharvest browning of cut or bruised fruit, but the native physiological functions of PPOs in undamaged, intact plant cells are not well understood. Walnut (Juglans regia) produces a rich array of phenolic compounds and possesses a single PPO enzyme, rendering it an ideal model to study PPO. We generated a series of PPO-silenced transgenic walnut lines that display less than 5% of wild-type PPO activity. Strikingly, the PPO-silenced plants developed spontaneous necrotic lesions on their leaves in the absence of pathogen challenge (i.e. a lesion mimic phenotype). To gain a clearer perspective on the potential functions of PPO and its possible connection to cell death, we compared the leaf transcriptomes and metabolomes of wild-type and PPO-silenced plants. Silencing of PPO caused major alterations in the metabolism of phenolic compounds and their derivatives (e.g. coumaric acid and catechin) and in the expression of phenylpropanoid pathway genes. Several observed metabolic changes point to a direct role for PPO in the metabolism of tyrosine and in the biosynthesis of the hydroxycoumarin esculetin in vivo. In addition, PPO-silenced plants displayed massive (9-fold) increases in the tyrosine-derived metabolite tyramine, whose exogenous application elicits cell death in walnut and several other plant species. Overall, these results suggest that PPO plays a novel and fundamental role in secondary metabolism and acts as an indirect regulator of cell death in walnut.


Assuntos
Catecol Oxidase/metabolismo , Juglans/citologia , Juglans/enzimologia , Metabolismo Secundário , Morte Celular/efeitos dos fármacos , Cinamatos/metabolismo , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Inativação Gênica/efeitos dos fármacos , Juglans/efeitos dos fármacos , Juglans/genética , Cinética , Metabolômica , Fenótipo , Extratos Vegetais/metabolismo , Folhas de Planta/citologia , Folhas de Planta/efeitos dos fármacos , Folhas de Planta/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas , Propanóis/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Metabolismo Secundário/efeitos dos fármacos , Metabolismo Secundário/genética , Especificidade por Substrato/efeitos dos fármacos , Tiramina/química , Tiramina/metabolismo , Tiramina/farmacologia
10.
F1000Res ; 3: 295, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-26629331

RESUMO

The therapeutic potential of α-helical anti-microbial peptides (AH-AMP) to combat pathogens is fast gaining prominence. Based on recently published open access software for characterizing α-helical peptides (PAGAL), we elucidate a search methodology (SCALPEL) that leverages the massive structural data pre-existing in the PDB database to obtain AH-AMPs belonging to the host proteome. We provide in vitro validation of SCALPEL on plant pathogens ( Xylella fastidiosa, Xanthomonas arboricola and Liberibacter crescens) by identifying AH-AMPs that mirror the function and properties of cecropin B, a well-studied AH-AMP. The identified peptides include a linear AH-AMP present within the existing structure of phosphoenolpyruvate carboxylase (PPC20), and an AH-AMP mimicing the properties of the two α-helices of cecropin B from chitinase (CHITI25). The minimum inhibitory concentration of these peptides are comparable to that of cecropin B, while anionic peptides used as control failed to show any inhibitory effect on these pathogens. Substitute therapies in place of conventional chemotherapies using membrane permeabilizing peptides like these might also prove effective to target cancer cells. The use of native structures from the same organism could possibly ensure that administration of such peptides will be better tolerated and not elicit an adverse immune response. We suggest a similar approach to target Ebola epitopes, enumerated using PAGAL recently, by selecting suitable peptides from the human proteome, especially in wake of recent reports of cationic amphiphiles inhibiting virus entry and infection.

11.
PLoS One ; 8(9): e74256, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24086326

RESUMO

Next-generation sequencing was exploited to gain deeper insight into the response to infection by Candidatus liberibacter asiaticus (CaLas), especially the immune disregulation and metabolic dysfunction caused by source-sink disruption. Previous fruit transcriptome data were compared with additional RNA-Seq data in three tissues: immature fruit, and young and mature leaves. Four categories of orchard trees were studied: symptomatic, asymptomatic, apparently healthy, and healthy. Principal component analysis found distinct expression patterns between immature and mature fruits and leaf samples for all four categories of trees. A predicted protein - protein interaction network identified HLB-regulated genes for sugar transporters playing key roles in the overall plant responses. Gene set and pathway enrichment analyses highlight the role of sucrose and starch metabolism in disease symptom development in all tissues. HLB-regulated genes (glucose-phosphate-transporter, invertase, starch-related genes) would likely determine the source-sink relationship disruption. In infected leaves, transcriptomic changes were observed for light reactions genes (downregulation), sucrose metabolism (upregulation), and starch biosynthesis (upregulation). In parallel, symptomatic fruits over-expressed genes involved in photosynthesis, sucrose and raffinose metabolism, and downregulated starch biosynthesis. We visualized gene networks between tissues inducing a source-sink shift. CaLas alters the hormone crosstalk, resulting in weak and ineffective tissue-specific plant immune responses necessary for bacterial clearance. Accordingly, expression of WRKYs (including WRKY70) was higher in fruits than in leaves. Systemic acquired responses were inadequately activated in young leaves, generally considered the sites where most new infections occur.


Assuntos
Citrus/genética , Redes Reguladoras de Genes , Doenças das Plantas/genética , Citrus/microbiologia , Reação em Cadeia da Polimerase , Transcriptoma
12.
Eur J Pediatr ; 172(5): 601-12, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23307281

RESUMO

UNLABELLED: In Europe, the introduction of monovalent meningococcal serogroup C (MenC) conjugate vaccines has resulted in a significant decline in MenC invasive disease. However, given the potential for strain evolution and increasing travel to areas of high endemicity, protection against additional serogroups is needed. In this study, the immunogenicity, measured by a serum bactericidal activity assay using rabbit complement (rSBA), and the safety of a quadrivalent meningococcal serogroups A, C, W-135 and Y tetanus toxoid conjugate vaccine (MenACWY-TT) were compared to that of a licensed monovalent MenC conjugate vaccine (MenC-CRM197) in children 2-10 years of age. Children were randomised (3:1) to receive a single dose of either MenACWY-TT or MenC-CRM197. Non-inferiority of the immunogenicity of MenACWY-TT versus MenC-CRM197 in terms of rSBA-MenC vaccine response was demonstrated. Exploratory analyses suggested that rSBA-MenC geometric mean titres adjusted for pre-vaccination titres were lower in children vaccinated with MenACWY-TT compared to MenC-CRM197. Nevertheless, at 1 month post-vaccination, ≥99.3 % of the children who received MenACWY-TT had rSBA titres ≥1:128 for each of the four vaccine serogroups, which is the more conservative correlate of protection. The reactogenicity and safety profile of MenACWY-TT was clinically acceptable and no serious adverse events considered related to vaccination were reported throughout the study. CONCLUSION: When administered to European school-age children, MenACWY-TT has a clinically acceptable safety profile and, when compared with MenC-CRM197, the potential to broaden protection against meningococcal disease caused by serogroups A, W-135 and Y while maintaining protection against MenC. This study has been registered at www.clinicaltrials.gov NCT00674583.


Assuntos
Infecções Meningocócicas/prevenção & controle , Vacinas Meningocócicas/administração & dosagem , Neisseria meningitidis/imunologia , Criança , Pré-Escolar , Feminino , França , Alemanha , Humanos , Masculino , Vacinas Meningocócicas/efeitos adversos , Vacinas Meningocócicas/imunologia
13.
PLoS One ; 7(5): e38039, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22675433

RESUMO

Huanglongbing (HLB) or "citrus greening" is the most destructive citrus disease worldwide. In this work, we studied host responses of citrus to infection with Candidatus Liberibacter asiaticus (CaLas) using next-generation sequencing technologies. A deep mRNA profile was obtained from peel of healthy and HLB-affected fruit. It was followed by pathway and protein-protein network analysis and quantitative real time PCR analysis of highly regulated genes. We identified differentially regulated pathways and constructed networks that provide a deep insight into the metabolism of affected fruit. Data mining revealed that HLB enhanced transcription of genes involved in the light reactions of photosynthesis and in ATP synthesis. Activation of protein degradation and misfolding processes were observed at the transcriptomic level. Transcripts for heat shock proteins were down-regulated at all disease stages, resulting in further protein misfolding. HLB strongly affected pathways involved in source-sink communication, including sucrose and starch metabolism and hormone synthesis and signaling. Transcription of several genes involved in the synthesis and signal transduction of cytokinins and gibberellins was repressed while that of genes involved in ethylene pathways was induced. CaLas infection triggered a response via both the salicylic acid and jasmonic acid pathways and increased the transcript abundance of several members of the WRKY family of transcription factors. Findings focused on the fruit provide valuable insight to understanding the mechanisms of the HLB-induced fruit disorder and eventually developing methods based on small molecule applications to mitigate its devastating effects on fruit production.


Assuntos
Citrus/genética , Doenças das Plantas/genética , Doenças das Plantas/microbiologia , Transcriptoma , Análise de Variância , Metabolismo dos Carboidratos/genética , Citrus/imunologia , Citrus/microbiologia , Biologia Computacional , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Sequenciamento de Nucleotídeos em Larga Escala , Modelos Biológicos , Fotossíntese/genética , Doenças das Plantas/imunologia , Reguladores de Crescimento de Plantas/metabolismo , Dobramento de Proteína , Estabilidade Proteica , Rhizobiaceae , Transdução de Sinais , Fatores de Transcrição/genética
14.
J Agric Food Chem ; 57(7): 2786-92, 2009 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-19253953

RESUMO

The plant hormone ethylene regulates climacteric fruit ripening and plays a major role in the development of superficial scald in apple fruits during cold storage. The effect of cold storage at 0 degrees C on development of superficial scald and bitter pit (BP) in transgenic Greensleeves (GS) apples suppressed for ethylene biosynthesis was investigated. Four apple lines were used: untransformed GS; line 68G, suppressed for 1-aminocyclopropane-1-carboxylic acid (ACC) oxidase (ACO); and lines 103Yand 130Y, suppressed for ACC synthase (ACS). Fruits from the transformed lines 68G, 103Y, and 130Y produced very little ethylene during 3 months of cold storage at 0 degrees C and after subsequent transfer to 20 degrees C, whereas untransformed fruits produced significant ethylene during cold storage, which increased dramatically at 20 degrees C. Respiration, expressed as CO(2) production, was similar in all four apple lines. After 2 months at 0 degrees C, all apple lines showed some BP symptoms, but lines 68G and 103Y were more affected than untransformed GS or line 130Y. Both transformed and untransformed apples produced alpha-farnesene, but concentrations were lower in yellow fruit than in green fruit in all lines but 68G. Line 68G produced the most alpha-farnesene after 2 months at 0 degrees C, including both (E,E) alpha-farnesene and (Z,E) alpha-farnesene. Concentrations of (E,E) alpha-farnesene were 100 times greater than those of (Z,E) alpha-farnesene in all lines. After 4 months at 0 degrees C plus 1 week at 20 degrees C, untransformed GS apples exhibited the most superficial scald, whereas fruits from lines 68G and 103Y were less affected and line 130Y had no scald. Superficial scald severity was higher in green fruit than in yellow fruit in all affected lines. These lines also exhibited significant production of 6-methyl-5-hepten-2-one (MHO), a major oxidation product of (E,E) alpha-farnesene. Line 130Y neither exhibited superficial scald nor produced MHO. It is shown here that even transgenic apples suppressed for ethylene biosynthesis genes can produce alpha-farnesene, which in turn can oxidize to free radicals and MHO, leading to scald development.


Assuntos
Temperatura Baixa , Etilenos/biossíntese , Conservação de Alimentos , Frutas/metabolismo , Malus/genética , Plantas Geneticamente Modificadas/metabolismo , Aminoácido Oxirredutases/genética , Aminoácido Oxirredutases/metabolismo , Temperatura Baixa/efeitos adversos , Conservação de Alimentos/métodos , Liases/genética , Liases/metabolismo , Oxirredução , Sesquiterpenos/metabolismo
15.
Dent Traumatol ; 20(3): 123-33, 2004 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-15144442

RESUMO

This study describes the socio-economic burden and attitudes of children and their parents following replantation of avulsed incisors. Records of 80 patients with 99 avulsion injuries treated in a teaching hospital clinic from 1988 to 1999 were reviewed. Mean age at time of injury was 10.6 years (range = 6.6-17.7 years). Complete records for a minimum of 1 year were obtained for 43 patients with 60 replanted incisors. Mean treatment procedures provided during the first year included 5.5 diagnostic periapical radiographs, 1.9 occlusal radiographs, 1.3 pulpectomies, and 2.7 pulp medicament applications. The mean estimated treatment cost and direct time (dentist) for first-year post-trauma management was 1465 dollars CAD and 7.2 h, respectively. Treatment costs were significantly higher during the first year post-trauma for patients who had their incisors extracted (P = 0.04), but there was no significant difference in direct treatment time between the two groups (P = 0.19). Twenty-one patient-parent pairs were surveyed for a number of qualitative factors. Ninety per cent of patients and 86% of parents reported that school and work time was lost. Even after having gone through the painful experience of replantation, the demands of recall, and in some cases, extraction, the majority of patients (67%) and parents (81%) stated that they would have still made the same (replantation) decision. Patient and parent responses were not statistically different (P = 0.453). Almost half the parents stated they would be willing to pay over 2000 dollars CAD to save an incisor. Patients rated retention of an incisor as significantly more important than infraocclusion. This is the first study to quantify the treatment burden of replantation of avulsion injuries exclusively in the pediatric population. This study describes the socio-economic burden and responsibilities of patient/parent and dentist and their role in informed consent.


Assuntos
Atitude Frente a Saúde , Incisivo/lesões , Avulsão Dentária/economia , Reimplante Dentário/economia , Absenteísmo , Adolescente , Criança , Comportamento de Escolha , Efeitos Psicossociais da Doença , Feminino , Seguimentos , Custos de Cuidados de Saúde , Humanos , Masculino , Ontário , Pais/psicologia , Pulpectomia/economia , Radiografia Dentária/economia , Estudos Retrospectivos , Tratamento do Canal Radicular/economia , Fatores de Tempo , Avulsão Dentária/psicologia , Extração Dentária/economia , Reimplante Dentário/psicologia
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