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1.
Plant Dis ; 103(8): 1954-1960, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31169085

RESUMO

Pseudomonas syringae pv. syringae, a Gammaproteobacterium belonging to genomospecies 2 within the P. syringae complex, is distributed worldwide, and it is responsible for bacterial canker on >100 different hosts, including the grapevine. P. syringae pv. syringae induces necrotic lesions in the leaf blades, veins, petioles, shoots, rachis, and tendrils on grapevine cultivars in different areas. P. syringae pv. syringae has been associated with severe economic losses in different grape cultivars in Australia, where it causes inflorescence rot. In midsummer to late summer 2017, symptoms of berry rots differing from those caused by the common berry rots agents were observed in different cultivar Red Globe vineyards of Apulia (southern Italy). As proven by fulfillment of Koch's postulates, these symptoms were caused by a bacterium that, according to the results of biochemical, physiological, nutritional, antimicrobial activity, and pathogenicity tests and sequencing of 16S ribosomal DNA, gyrB, rpoB, and rpoD genes, was identified as P. syringae pv. syringae. This is the first report of Pseudomonas grapevine bunch rot.


Assuntos
Doenças das Plantas , Pseudomonas syringae , Vitis , Austrália , Genes Bacterianos/genética , Itália , Doenças das Plantas/microbiologia , Pseudomonas syringae/genética , Pseudomonas syringae/patogenicidade , Pseudomonas syringae/fisiologia , Virulência , Vitis/microbiologia
2.
Mar Environ Res ; 183: 105806, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36459755

RESUMO

Coastal marine ecosystems have structural and functional features usually connected by the seasonal transfer of nutrients and organisms. These environments can utilize inter-ecosystem subsidies to increase resilience and maturity and support human activities like fishing. However, the importance of the connection and the role of the seasonal pulse of energy flows to enhance maturity are still poorly understood and reported. Our objective in this paper is to assess the effect of seasonal hydrological pulses on two tropical coastal interconnected ecosystems. Thus, we made four Ecopath models for estuarine and neritic environments considering the dry and rainy seasons, with a similar sampling design that allowed them to be compared. Our results provide evidence for the occurrence of the pulsed ecosystems since both environments seem driven by the river flow. Estuary presents more and more substantial differences (measured by ecosystem attributes) in both seasons because it is directly affected by river floods than the neritic environment. The neritic is affected indirectly by the movement of species from the estuary and by a weaker river flow. In the dry season, the differences between ecosystems are lower because the dry season trend to homogenize cycling, maturity, homeostasis, and resilience. We found that the seasonal river flow (pulse) forces the variability of biomass, flows, and ecosystem features, and this variance creates the required stability for both ecosystems. Still, these environments benefit through the exchange of components that relieve the pressures of predation on specific groups and maintain the energy flow necessary for the functioning of their trophic webs. The pulse by the rainfall favors connectivity and equalizes the two systems, increasing the connectivity between them and the exchange of subsidies that strengthens the trophic structures, contributing to the increase in maturity. In these ecosystems, seasonal changes become a key factor for exchanging flows that will promote sustainability, the accumulation of more biomass (growth), and the optimization of reserve energy (development) in both systems. This efficient joint strategy of perpetuation is what promotes resistance and resilience to these ecosystems, which together can reach different states of equilibrium, translated into maturity to withstand new environmental changes.


Assuntos
Ecossistema , Rios , Humanos , Biomassa , Estuários , Estações do Ano
3.
Mar Environ Res ; 184: 105858, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36630747

RESUMO

Macroalgal bloom events have been frequent in recent years. Eutrophication and overexploitation fishing may favor blooms through nutrient availability and capturing top predators. We aim to investigate the drivers of the macroalgae blooms and their consequences on the food web of the two tropical coastal ecosystems: Porto do Mangue (with high macroalgae production) and Baía Formosa (control environment, without macroalgae), both exploited by artisanal fisheries in northeastern Brazil. The food webs are modeled using the Ecopath with Ecosim (EwE) approach. Our results suggest that fishing did not favor macroalgae blooms but rather the high concentration of nutrients added to the semi-arid conditions. Furthermore, the macroalgae bloom showed low trophic impact, so much of their biomass is transferred into detritus. However, when it decomposes, this accumulation of matter alters the structure and functioning of the ecosystem, affecting its main fish resources: shrimp and piscivorous fish. Investigating blooms is key to management.


Assuntos
Ecossistema , Alga Marinha , Animais , Cadeia Alimentar , Pesqueiros , Biomassa , Eutrofização
4.
J Exp Bot ; 63(14): 5003-15, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22936828

RESUMO

Polyamines (PAs) are nitrogenous molecules which play a well-established role in most cellular processes during growth and development under physiological or biotic/abiotic stress conditions. The molecular mode(s) of PA action have only recently started to be unveiled, and comprehensive models for their molecular interactions have been proposed. Their multiple roles are exerted, at least partially, through signalling by hydrogen peroxide (H(2)O(2)), which is generated by the oxidation/back-conversion of PAs by copper amine oxidases and PA oxidases. Accumulating evidence suggests that in plants the cellular titres of PAs are affected by other nitrogenous compounds. Here, we discuss the state of the art on the possible nitrogen flow in PAs, their interconnection with nitrogen metabolism, as well as the signalling roles of PA-derived H(2)O(2) during some developmental processes and stress responses.


Assuntos
Peróxido de Hidrogênio/metabolismo , Nitrogênio/metabolismo , Fenômenos Fisiológicos Vegetais , Plantas/metabolismo , Poliaminas/metabolismo , Desenvolvimento Vegetal , Transdução de Sinais , Estresse Fisiológico
5.
J Phys Condens Matter ; 33(17)2021 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-33524963

RESUMO

Interpenetrated polymer network microgels, composed of crosslinked networks of poly(N-isopropylacrylamide) and polyacrylic acid (PAAc), have been investigated through rheological measurements at four different amounts of PAAc. Both PAAc content and crosslinking degree modify particle dimensions, mass and softness, thereby strongly affecting the volume fraction and the system viscosity. Here the volume fraction is derived from the flow curves at low concentrations by fitting the zero-shear viscosity with the Einstein-Batchelor equation which provides a parameterkto shift weight concentration to volume fraction. We find that particles with higher PAAc content and crosslinker are characterized by a greater value ofkand therefore by larger volume fractions when compared to softer particles. The packing fractions obtained from rheological measurements are compared with those from static light scattering for two PAAc contents revealing a good agreement. Moreover, the behaviour of the viscosity as a function of packing fraction, at room temperature, has highlighted an Arrhenius dependence for microgels synthesized with low PAAc content and a Vogel-Fulcher-Tammann dependence for the highest investigated PAAc concentration. A comparison with the hard spheres behaviour indicates a steepest increase of the viscosity with decreasing particles softness. Finally, the volume fraction dependence of the viscosity at a fixed PAAc and at two different temperatures, below and above the volume phase transition, shows a quantitative agreement with the structural relaxation time measured through dynamic light scattering indicating that interpenetrated polymer network microgels softness can be tuned with PAAc and temperature and that, depending on particle softness, two different routes are followed.

6.
Rev Sci Instrum ; 92(2): 023907, 2021 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-33648116

RESUMO

Dynamic Light Scattering (DLS) and Small-Angle Neutron Scattering (SANS) are two key tools to probe the dynamic and static structure factors, respectively, in soft matter. Usually, DLS and SANS measurements are performed separately, in different laboratories, on different samples, and at different times. However, this methodology has particular disadvantages for a large variety of soft materials, which exhibit a high sensitivity to small changes in fundamental parameters, such as waiting times, concentration, pH, and ionic strength. Here, we report on a new portable DLS-SANS apparatus that allows one to simultaneously measure both the microscopic dynamics (through DLS) and the static structure (through SANS) on the same sample. The apparatus has been constructed as a collaboration between two laboratories, each an expert in one of the scattering methods, and was commissioned on the LOQ and ZOOM SANS instruments at the ISIS Pulsed Neutron and Muon Source, U.K.

7.
Phys Rev Lett ; 104(8): 085701, 2010 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-20366947

RESUMO

Using experiments, theory and simulations, we show that the arrested state observed in a colloidal clay at high concentrations is stabilized by screened Coulomb repulsion (Wigner glass). Dilution experiments allow us to distinguish this disconnected state, which melts upon addition of water, from a low-concentration gel state, which does not melt. Theoretical modeling and simulations at high concentrations reproduce the measured small angle x-ray scattering static structure factors and confirm the long-range electrostatic nature of the arrested structure. These findings are attributed to the different time scales controlling the competing attractive and repulsive interactions.

8.
Carbohydr Polym ; 221: 209-220, 2019 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-31227160

RESUMO

Hyaluronan (HA) is among the most used biopolymers for viscosupplementation and dermocosmetics. However, the current injectable HA-based formulations present relevant limitations: I) unmodified HA is quickly degraded by endogenous hyaluronidases (HAase), resulting in short lasting properties; II) cross-linked HA, although shows enhanced stability against HAase, often contains toxic chemical cross-linkers. As such, herein, we present biocompatible self-assembled hyaluronan-cholesterol nanohydrogels (HA-CH NHs) able to bind to HAase and inhibit the enzyme activity in vitro, more efficiently than currently marketed HA-based cross-linked formulations (e.g. Jonexa™). HA-CH NHs inhibit HAase through a mixed mechanism, by which NHs bind to HAase with an affinity constant 7-fold higher than that of native HA. Similar NHs, based on gellan-CH, evidenced no binding to HAase, neither inhibition of the enzyme activity, suggesting this effect might be due to the specific binding of HA-CH to the active site of the enzyme. Therefore, HA-CH NHs were engineered into injectable hybrid HA mixtures or physical hydrogels, able to halt the enzymatic degradation of HA.


Assuntos
Colesterol/análogos & derivados , Inibidores Enzimáticos/química , Ácido Hialurônico/análogos & derivados , Hialuronoglucosaminidase/antagonistas & inibidores , Hidrogéis/química , Materiais Biocompatíveis/síntese química , Materiais Biocompatíveis/química , Materiais Biocompatíveis/toxicidade , Linhagem Celular , Colesterol/síntese química , Colesterol/toxicidade , Composição de Medicamentos , Inibidores Enzimáticos/síntese química , Inibidores Enzimáticos/toxicidade , Humanos , Ácido Hialurônico/síntese química , Ácido Hialurônico/toxicidade , Hialuronoglucosaminidase/química , Hidrogéis/síntese química , Hidrogéis/toxicidade , Nanoestruturas/química , Nanoestruturas/toxicidade
9.
Lancet ; 370(9602): 1840-6, 2007 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-18061059

RESUMO

BACKGROUND: Chikungunya virus (CHIKV), which is transmitted by Aedes spp mosquitoes, has recently caused several outbreaks on islands in the Indian Ocean and on the Indian subcontinent. We report on an outbreak in Italy. METHODS: After reports of a large number of cases of febrile illness of unknown origin in two contiguous villages in northeastern Italy, an outbreak investigation was done to identify the primary source of infection and modes of transmission. An active surveillance system was also implemented. The clinical case definition was presentation with fever and joint pain. Blood samples were gathered and analysed by PCR and serological assays to identify the causal agent. Locally captured mosquitoes were also tested by PCR. Phylogenetic analysis of the CHIKV E1 region was done. FINDINGS: Analysis of samples from human beings and from mosquitoes showed that the outbreak was caused by CHIKV. We identified 205 cases of infection with CHIKV between July 4 and Sept 27, 2007. The presumed index case was a man from India who developed symptoms while visiting relatives in one of the villages. Phylogenetic analysis showed a high similarity between the strains found in Italy and those identified during an earlier outbreak on islands in the Indian Ocean. The disease was fairly mild in nearly all cases, with only one reported death. INTERPRETATION: This outbreak of CHIKV disease in a non-tropical area was to some extent unexpected and emphasises the need for preparedness and response to emerging infectious threats in the era of globalisation.


Assuntos
Aedes/virologia , Infecções por Alphavirus/epidemiologia , Vírus Chikungunya/patogenicidade , Surtos de Doenças , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Infecções por Alphavirus/fisiopatologia , Animais , Vírus Chikungunya/isolamento & purificação , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Itália/epidemiologia , Masculino , Pessoa de Meia-Idade , Viagem
10.
Phys Rev E Stat Nonlin Soft Matter Phys ; 78(2 Pt 1): 020502, 2008 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18850776

RESUMO

The phase diagram of alpha -cyclodextrin/water/4-methylpyridine solutions, a system undergoing inverse melting, has been studied by differential scanning calorimetry, rheological methods, and x-ray diffraction. Two different fluid phases separated by a solid region have been observed in the high alpha -cyclodextrin concentration range (c > or =150 mg/ml) . Decreasing c , the temperature interval where the solid phase exists decreases and eventually disappears, and a first-order phase transition is observed between the two different fluid phases.

11.
Phys Rev E Stat Nonlin Soft Matter Phys ; 77(2 Pt 1): 020402, 2008 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18351973

RESUMO

The aging of a charged colloidal system has been studied by small-angle x-ray scattering, in the exchanged momentum range Q=0.03-5 nm(-1) , and by dynamic light scattering, at different clay concentrations (C(w)=0.6-2.8%) . The static structure factor S(Q) has been determined as a function of both aging time and concentration. This is the direct experimental evidence of the existence and evolution with aging time of two different arrested states in a single system simply obtained only by changing its volume fraction: an inhomogeneous state is reached at low concentrations, while a homogeneous one is found at high concentrations.

12.
Plant Dis ; 102(9): 1708-1717, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30125154

RESUMO

Monilinia spp. are responsible for brown rot decay of stone and pome fruit in the field as well as in postharvest. Monilinia laxa and M. fructigena are considered indigenous to Europe, while M. fructicola is a quarantine pathogen in the European and Mediterranean Plant Protection Organization area included in the A2 List. In Italy, it was first reported in 2009 in Piedmont (northern Italy) and rapidly spread to central Italy. We carried out a monitoring program on the occurrence of Monilinia spp. in southern Italy and a comparative characterization of the three main fungal pathogens. Molecular assays based on direct polymerase chain reaction (PCR) and real-time quantitative PCR for molecular identification of Monilinia spp. from rotted fruit were set up, validated, and applied in a monitoring program. Of the tested 519 isolates from 26 orchards, 388 (74.8%) were identified as M. fructicola, 118 (22.7%) as M. laxa, 10 (1.9%) as M. fructigena, and 3 (0.6%) were M. polystroma. M. fructicola colonies grew faster and had a higher optimal temperature for growth (26°C) than M. laxa (23°C) and M. fructigena (20°C). No relevant difference in virulence could be observed on artificially inoculated apricot, cherry, and peach fruit. The fungal species showed different responses to fungicides, because M. fructicola was more sensitive than M. laxa, especially to cyflufenamid, and M. fructigena revealed a lower sensitivity to succinate dehydrogenase inhibitors (boscalid, fluopyram, and fluxapyroxad) and quinone outside inhibitors (mandestrobin). In summary, the two species M. fructicola and M. polystroma were first detected in southern Italy where M. fructicola has largely displaced the two indigenous pathogens M. laxa and M. fructigena; the relative proportions of the three pathogens in orchards should be considered when defining the management of brown rot of stone fruit due to differences in their responses to fungicides.


Assuntos
Ascomicetos/isolamento & purificação , Fungicidas Industriais/farmacologia , Doenças das Plantas/microbiologia , Prunus/microbiologia , Ascomicetos/classificação , Ascomicetos/efeitos dos fármacos , Ascomicetos/patogenicidade , Frutas/microbiologia , Itália , Reação em Cadeia da Polimerase
13.
Structure ; 7(3): 265-76, 1999 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-10368296

RESUMO

BACKGROUND: Polyamines are essential for cell growth and differentiation; compounds interfering with their metabolism are potential anticancer agents. Polyamine oxidase (PAO) plays a central role in polyamine homeostasis. The enzyme utilises an FAD cofactor to catalyse the oxidation of the secondary amino groups of spermine and spermidine. RESULTS: The first crystal structure of a polyamine oxidase has been determined to a resolution of 1.9 Angstroms. PAO from Zea mays contains two domains, which define a remarkable 30 Angstrom long U-shaped catalytic tunnel at their interface. The structure of PAO in complex with the inhibitor MDL72527 reveals the residues forming the catalytic machinery and unusual enzyme-inhibitor CH.O H bonds. A ring of glutamate and aspartate residues surrounding one of the two tunnel openings contributes to the steering of the substrate towards the inside of the tunnel. CONCLUSIONS: PAO specifically oxidizes substrates that have both primary and secondary amino groups. The complex with MDL72527 shows that the primary amino groups are essential for the proper alignment of the substrate with respect to the flavin. Conservation of an N-terminal sequence motif indicates that PAO is member of a novel family of flavoenzymes. Among these, monoamine oxidase displays significant sequence homology with PAO, suggesting a similar overall folding topology.


Assuntos
Oxirredutases atuantes sobre Doadores de Grupo CH-NH/química , Proteínas de Plantas/química , Conformação Proteica , Sequência de Aminoácidos , Sítios de Ligação , Domínio Catalítico , Cristalografia por Raios X , Inibidores Enzimáticos/farmacologia , Flavina-Adenina Dinucleotídeo/metabolismo , Glicosilação , Ligação de Hidrogênio , Modelos Moleculares , Dados de Sequência Molecular , Monoaminoxidase/química , Oxirredutases atuantes sobre Doadores de Grupo CH-NH/antagonistas & inibidores , Proteínas de Plantas/antagonistas & inibidores , Poliaminas/metabolismo , Processamento de Proteína Pós-Traducional , Putrescina/análogos & derivados , Putrescina/farmacologia , Alinhamento de Sequência , Homologia de Sequência de Aminoácidos , Especificidade por Substrato , Zea mays/enzimologia , Poliamina Oxidase
14.
Ann Ital Chir ; 76(1): 85-7, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-16035677

RESUMO

OBJECTIVE: The effectiveness of the urgent carotid TEA in patients with not stabilizes serious neurological symptoms, remains controversial. MATERIAL: The authors report on a case of a partial acute carotid thrombosis. The patient had outcomes of pulmonary tumor dealt with surgical removal of the medium right lobe. At admission, the neurological examination evidenced non specific neurological deficits to both the advanced limbs above all. The blood test evidenced 628000 platelets. The color-doppler showed in the internal carotid artery of right the presence of floating thrombus, during very small fibro-calcified plate, likely ulcerated. RESULTS: The patient was submitted to surgical urgent procedure without ulterior diagnostic deepening. Such attitude was justified from the total regression of the symptomatology and from the absence of alterations of the BEE. DISCUSSION: The urgent surgical treatment has had good outcome. In literature there are similar cases but not place upon ones because of "aetiology" to the inner presence of floating thrombus in carotid not completely occluding in all and the three cases, causes do not correspond from alters platelet parameters, but thrombus was of cardiogenic origin in one case, it was caused by hormonal therapy for sterility in the second, there was thrombosis of carotid aneurysm in third. CONCLUSION: We remark the importance of eco-color Doppler for urgent diagnosis of acute thrombosis, and timeliness of surgical treatment in the "acute" patient with attenuation or regression of the debut symptomatology.


Assuntos
Trombose das Artérias Carótidas/cirurgia , Artéria Carótida Interna , Endarterectomia das Carótidas , Trombose das Artérias Carótidas/diagnóstico por imagem , Endarterectomia das Carótidas/métodos , Humanos , Masculino , Pessoa de Meia-Idade , Resultado do Tratamento , Ultrassonografia Doppler em Cores
15.
Braz J Biol ; 75(1): 144-51, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25945631

RESUMO

Alterations in aquatic systems and changes in water levels, whether due to rains or dam-mediated control can cause changes in community structure, forcing the community to readjust to the new environment. This study tested the hypothesis that there is an increase in the richness and abundance of aquatic insects during the rainy season in the Serra da Mesa Reservoir, with the premise that increasing the reservoir level provides greater external material input and habitat diversity, and, therefore, conditions that promote colonization by more species. We used the paired t test to test the differences in richness, beta diversity, and abundance, and a Non-metric Multidimensional Scaling (NMDS) was performed to identify patterns in the community under study. Additionally, Pearson correlations were analyzed between the richness, abundance, and beta diversity and the level of the reservoir. We collected 35,028 aquatic insect larvae (9,513 in dry period and 25,515 in the rainy season), predominantly of the Chironomidae family, followed by orders Ephemeroptera, Trichoptera, and Odonata. Among the 33 families collected, only 12 occurred in the dry season, while all occurred in the rainy season. These families are common in lentic environments, and the dominance of Chironomidae was associated with its fast colonization, their behavior of living at high densities and the great tolerance to low levels of oxygen in the environment. The hypothesis was confirmed, as the richness, beta diversity, and abundance were positively affected by the increase in water levels due to the rainy season, which most likely led to greater external material input, greater heterogeneity of habitat, and better conditions for colonization by several families.


Assuntos
Biodiversidade , Insetos/classificação , Animais , Brasil , Água Doce , Densidade Demográfica , Estações do Ano , Clima Tropical
16.
Clin Ter ; 166(6): 238-43, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26794810

RESUMO

BACKGROUND: Psychological disorders are often associated with diseases of the upper digestive tract. Although emotions can influence gastrointestinal function in healthy individuals, psychological setting in upper gastrointestinal patients are unclear. We evaluate the psychological alterations prevalence in outpatients submitted to upper endoscopy. MATERIALS AND METHODS: A total of 130 patients (50 males and 80 females; mean age 54±17 years) submitted to upper gastrointestinal endoscopy, were enrolled over the period May 2009 - September 2010. Subjects were asked to complete questionnaires before endoscopic examination. Alexithymia, anxiety, depression and coping style were assessed using the Toronto Alexithymia Scale, Spielberger Trait Anxiety Inventory, Beck Depression Inventory and Coping Inventory for Stressful Situations, respectively. RESULTS: Coping impairment, Alexithymia, Anxiety and Depression were found respectively in 80.3%, 25.4%, 24.6% and 17.2%, often in association. Task-oriented, emotion-oriented and avoidance-oriented alterations were found in 41.8%, 40% and 30.6%, respectively. No correlations were demonstrated between diagnosis of upper gastrointestinal disease and psychometric results. CONCLUSIONS: In our study, a high prevalence of psychometric alterations in gastrointestinal outpatients was unconnected with endoscopic findings, especially considering coping style alterations. This aspect should be taken into account in patients management and a long-term follow-up should clarify a possible role of these factors in patients prognosis and compliance.


Assuntos
Adaptação Psicológica , Sintomas Afetivos/complicações , Ansiedade/complicações , Depressão/complicações , Endoscopia Gastrointestinal , Gastroenteropatias/psicologia , Escalas de Graduação Psiquiátrica , Adulto , Sintomas Afetivos/diagnóstico , Sintomas Afetivos/epidemiologia , Idoso , Assistência Ambulatorial , Ansiedade/diagnóstico , Ansiedade/epidemiologia , Estudos Transversais , Depressão/diagnóstico , Depressão/epidemiologia , Feminino , Gastroenteropatias/diagnóstico , Humanos , Masculino , Pessoa de Meia-Idade , Prevalência , Testes Psicológicos , Psicometria , Estresse Psicológico/complicações , Estresse Psicológico/diagnóstico , Estresse Psicológico/epidemiologia , Inquéritos e Questionários
17.
FEBS Lett ; 437(3): 177-82, 1998 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-9824285

RESUMO

A chickpea cDNA encoding a cell wall copper amine oxidase (CuAO) was cloned and characterised. The 2010 bp open reading frame encodes a protein of 76.5 kDa which shares significant primary structure homology with other known CuAOs. Southern blot analysis indicates that in chickpea CuAO is encoded by a single gene or a small gene family. This cDNA was essential for studying the role of CuAO during seedling development and wound healing in chickpea seedlings. CuAO transcript level and activity were modulated during seedling development in parallel with cell maturation. Moreover, mechanical wounding induced a rapid increase of CuAO mRNA accumulation and enzyme activity which remained high during the wound-healing process. Aminoguanidine, a specific CuAO inhibitor, decreased the deposition of lignin-suberin barrier along the lesion. CuAO may be a limiting factor in H2O2 production in the cell wall of chickpea seedlings and its expression seems to integrate with the remodelling of plant cell wall occurring during ontogenesis and wound healing.


Assuntos
Amina Oxidase (contendo Cobre)/genética , Parede Celular/enzimologia , Regulação da Expressão Gênica no Desenvolvimento , Regulação da Expressão Gênica de Plantas , Plantas/genética , Amina Oxidase (contendo Cobre)/metabolismo , Sequência de Aminoácidos , Sequência de Bases , Parede Celular/genética , Clonagem Molecular , DNA Complementar/análise , DNA Complementar/isolamento & purificação , Ativação Enzimática/efeitos dos fármacos , Fabaceae , Guanidinas/farmacologia , Lignina/metabolismo , Lipídeos , Lipídeos de Membrana/metabolismo , Dados de Sequência Molecular , Desenvolvimento Vegetal , Plantas/enzimologia , Plantas Medicinais , RNA Mensageiro/metabolismo
18.
FEBS Lett ; 426(1): 62-6, 1998 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-9598979

RESUMO

The first complete amino acid sequence of a flavin-containing polyamine oxidase was solved by a combined approach of nucleotide and peptide sequence analysis. A cDNA of 1737 bp, isolated from maize seedlings by reverse transcription-polymerase chain reaction and rapid amplification of cDNA ends strategies, was cloned and its sequence determined. This cDNA contains information for a polypeptide chain of 500 amino acids. Its amino-terminal sequence shows the typical features of secretion signal peptides. The primary structure of the mature protein was independently confirmed by extensive amino acid sequencing. Structural relationships with flavin-containing monoamine oxidases are also discussed.


Assuntos
Oxirredutases atuantes sobre Doadores de Grupo CH-NH/química , Zea mays/enzimologia , Sequência de Aminoácidos , Sequência de Bases , DNA Complementar/genética , Dados de Sequência Molecular , Monoaminoxidase/química , Oxirredutases atuantes sobre Doadores de Grupo CH-NH/genética , Proteínas de Plantas/química , Proteínas de Plantas/genética , Alinhamento de Sequência , Homologia de Sequência de Aminoácidos , Zea mays/genética , Poliamina Oxidase
19.
Ann Thorac Surg ; 58(1): 185-90, 1994 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-8037521

RESUMO

From October 1991 to May 1993, 130 patients were submitted to myocardial revascularization using complex preformed arterial conduits. The age ranged from 29 to 75 years (mean age, 60.1 years); 121 patients were male. One hundred twenty-six patients had double- or triple-vessel disease. The mean ejection fraction was 0.53 (range, 0.22 to 0.79); only 6 patients had an ejection fraction less than 0.35. In 6 cases the procedure was a reoperation. We used 360 arterial conduits, 163 of which as free grafts (3 left internal mammary arteries, 16 right internal mammary arteries, 86 inferior epigastric arteries, 57 radial arteries, and 1 right gastroepiploic artery). One hundred fifty-four free grafts were anastomosed to one or both internal mammary arteries and one to a radial artery. We constructed 136 complex arterial conduits (branched, lengthened, or both). In 6 cases a double arterial system had to be used in a single patient. There was no operative mortality, and no inotropic or mechanical supports were used. The overall mortality rate was 1.5%. Early angiographic controls (between the 7th and 15th postoperative days) demonstrated 100% patency; late angiographic controls (at a mean interval of 9.5 months after operation) documented a mean patency rate ranging from 94.1% of the radial arteries to 100% of the left internal mammary arteries and right gastroepiploic arteries. At a mean follow-up of 7.2 months (range, 1 to 15 months) all patients are alive without recurrence of symptoms.


Assuntos
Doença das Coronárias/cirurgia , Revascularização Miocárdica/métodos , Anastomose Cirúrgica/métodos , Angiografia Coronária , Doença das Coronárias/diagnóstico por imagem , Doença das Coronárias/epidemiologia , Feminino , Seguimentos , Humanos , Anastomose de Artéria Torácica Interna-Coronária/métodos , Masculino , Artéria Torácica Interna/transplante , Pessoa de Meia-Idade , Revascularização Miocárdica/mortalidade , Artéria Radial/transplante , Fatores de Tempo , Grau de Desobstrução Vascular/fisiologia
20.
Phytochemistry ; 29(8): 2411-4, 1990.
Artigo em Inglês | MEDLINE | ID: mdl-1366693

RESUMO

Some structural and biochemical characteristics of polyamine oxidase (PAO) purified from maize shoots have been examined. The enzyme has only alanine as N-terminal amino acid and its N-terminal sequence shows a significant degree of homology with tryptophan 2-monooxygenase from Pseudomonas syringae pv. savastanoi. The pH optimum for the stability of the native enzyme is 5, similar to that of the barley leaf enzyme. Calorimetric analysis shows a single two-state transition at pH 6 with Tm 49.8 degrees. At pH 5 the thermal stability is increased by more than 14 degrees. Amine oxidation products, delta 1-pyrroline and diazabicyclononane, are competitive inhibitors of PAO activity (apparent Ki = 400 and 100 microM respectively). Moreover these compounds improve the thermal stability of the enzyme. N1-Acetylspermine, which is a good substrate for mammalian PAO, acts as a non-competitive inhibitor for the plant enzyme.


Assuntos
Oxirredutases atuantes sobre Doadores de Grupo CH-NH/análise , Zea mays/enzimologia , Sequência de Aminoácidos , Colorimetria , Temperatura Alta , Dados de Sequência Molecular , Oxirredutases atuantes sobre Doadores de Grupo CH-NH/antagonistas & inibidores , Poliamina Oxidase
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