955 resultados para POSTHARVEST BROWN-ROT
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Festuccia WT, Blanchard PG, Oliveira TB, Magdalon J, Paschoal VA, Richard D, Deshaies Y. PPAR gamma activation attenuates cold-induced upregulation of thyroid status and brown adipose tissue PGC-1 alpha and D2. Am J Physiol Regul Integr Comp Physiol 303: R1277-R1285, 2012. First published October 24, 2012; doi:10.1152/ajpregu.00299.2012.-Here, we investigated whether pharmacological PPAR gamma activation modulates key early events in brown adipose tissue (BAT) recruitment induced by acute cold exposure with the aim of unraveling the interrelationships between sympathetic and PPAR gamma signaling. Sprague-Dawley rats treated or not with the PPAR gamma ligand rosiglitazone (15 mg.kg(-1).day(-1), 7 days) were kept at 23 degrees C or exposed to cold (5 degrees C) for 24 h and evaluated for BAT gene expression, sympathetic activity, thyroid status, and adrenergic signaling. Rosiglitazone did not affect the reduction in body weight gain and the increase in feed efficiency, VO2, and BAT sympathetic activity induced by 24-h cold exposure. Rosiglitazone strongly attenuated the increase in serum total and free T4 and T3 levels and BAT iodothyronine deiodinase type 2 (D2) and PGC-1 alpha mRNA levels and potentiated the reduction in BAT thyroid hormone receptor (THR) beta mRNA levels induced by cold. Administration of T3 to rosiglitazone-treated rats exacerbated the cold-induced increase in energy expenditure but did not restore a proper activation of D2 and PGC-1 alpha, nor further increased uncoupling protein 1 expression. Regarding adrenergic signaling, rosiglitazone did not affect the changes in BAT cAMP content and PKA activity induced by cold. Rosiglitazone alone or in combination with cold increased CREB binding to DNA, but it markedly reduced the expression of one of its major coactivators, CREB binding protein. In conclusion, pharmacological PPAR gamma activation impairs short-term cold elicitation of BAT adrenergic and thyroid signaling, which may result in abnormal tissue recruitment and thermogenic activity.
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This research evaluated the natural resistance of Platanus x acerifolia, Luehea divaricate, Carya illinoinensis, Peltophorum dubium, Araucaria angustifolia, Eucalyptus grandis and Hovenia dulcis, to accelerated decay of the white-rot fungus Pycnoporus sanguineus. The Specific Density at 12% was determinated. The accelerated decay test was conducted with glass bottles (capacity of 500 mL) filled with 100 g of moist soil, autoclaved, and kept at 25 degrees C. The initial establishment of fungal colonies on plates was supported by samples of Pinus elliottii sapwood. In this study, three samples of dimensions 9.0 x 25.0 x 25.0 mm were used for each species evaluated and, after 16 weeks of incubation, the percentage loss of mass was calculated. The degree of natural resistance was performed according to the percentages of mass loss. The results obtained from weight loss were compared by Tukey test at 5%. The natural resistance of woods was not influenced by specific gravity The wood of Carya illinoinensis, Eucalyptus grandis, Platanus x acerifolia, Luehea divaricata and Peltophorum dubium were classified as very resistant, Houvenia dulcis as resistant and Araucaria angustifolia as moderate resistant.
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Generation means was used to study the mode of inheritance of resistance to anthracnose stalk rot in tropical maize. Each population was comprised of six generations in two trials under a randomized block design. Inoculations were performed using a suspension of 105 conidia mL(-1) applied into the stalk. Internal lesion length was directly measured by opening the stalk thirty days after inoculation. Results indicated contrasting modes of inheritance. In one population, dominant gene effects predominated. Besides, additive x dominant and additive x additive interactions were also found. Intermediate values of heritability indicated a complex resistance inheritance probably conditioned by several genes of small effects. An additive-dominant genetic model sufficed to explain the variation in the second population, where additive gene effects predominated. Few genes of major effects control disease resistance in this cross. Heterosis widely differed between populations, which can be attributed to the genetic background of the parental resistant lines.
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A previous study from our laboratory showed that maternal food restriction (MFR) delays thermoregulation in newborn rats. In neonates brown adipose tissue (BAT) is essential for thermogenesis due to the presence of uncoupling proteins (UCPs). The aim of this study was to evaluate the influence of MFR on the UCPs mRNA and protein expression in BAT and skeletal muscle (SM) of the newborn rat. Female Wistar EPM-1 control rats (CON) received chow ad libitum during pregnancy, whereas food-restricted dams (RES) received 50% of the amount ingested by CON. Fifteen hours after birth, the litters were weighed and sacrificed. Blood was collected for hormonal analysis. BAT and SM were used for determination of UCPs mRNA and protein expression, and Ca2+-ATPase sarcoplasmic reticulum (SERCA1). RES pups showed a significant reduction in body weight and fat content at birth. MFR caused a significant increase in the expression of UCP1 and UCP2 in BAT, without changes in UCP3 and SERCA1 expression in BAT and SM. No differences between groups were found for leptin, T4 and glucose levels. RES pups showed increased insulin and decreased T3 levels. The delay in development of thermoregulation previously described in RES animals appears not to result from impairment in thermogenesis, but from an increase in heat loss, since MFR caused low birth weight in pups, leading to greater surface/volume ratio. The higher expression of UCP1 and UCP2 in BAT suggests a compensatory mechanism to increased thermogenesis. (C) 2011 Elsevier Ltd. All rights reserved.
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Pinus taeda wood chips were treated with the biopulping fungus Ceriporiopsis subvermispora in calcium-or oxalic acid-amended cultures. The secretion of hydrolytic and oxidative enzymes was inhibited only in the cultures having the highest concentration of calcium (1400 mg kg(-1) wood). Calcium decreased the availability of free oxalic acid, inhibited fungal growth, and reduced lignin mineralization and transformations. Oxalic acid amendment in the cultures was found not to affect the lignin mineralization and transformations; however, it did inhibit the depolymerization reactions detectable in the residual lignin that was retained in the biotreated wood. C. subvermispora presented catabolic activity for oxalic acid in the cultures amended with 1660 mg acid kg(-1) wood, whereas oxalic acid was synthesized when it was amended at low amounts or initially absent in the cultures. These data suggest one ideal ratio of oxalic acid in C. subvermispora cultures and indicate that its exogenous addition does not necessarily accompany the further degradation of lignin. Crown Copyright (C) 2012 Published by Elsevier Ltd. All rights reserved.
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The composition and seasonal variation of brachyuran and anomuran species associated with mussel farms were evaluated at Praia da Cocanha, Sao Paulo between May 2007 and February 2008. Nine mussel ropes were sampled at random in each quarter, and 1,208 organisms were identified, comprising five families and 28 species. The most numerous species was the porcellanid Pachycheles laevidactylus (18.5%), followed by the xanthids Acantholobulus schmitti (16.6%), Hexapanopeus paulensis (11.3%), Panopeus americanus (10.2%), and Menippe nodifrons (8.4%). The exotic crab Charybdis hellerii was recorded throughout the study period. The ecological descriptors, except Pielou evenness index, varied significantly over the time. The highest abundance and diversity of the species were recorded during November and February. This pattern was reversed for Berger-Parker dominance, with the lowest values recorded in February. The development of epifauna was correlated with the different stages of the mussel farms, since the mean size of mussels and consequently the abundance of epibiotic organisms and the structural complexity on the mussel ropes increased from May (seeding) until February (harvest). Despite this, the temporal population variations in recruitment patterns of the different epibionts should not be overlooked. The results indicated that the mussel farms provided favorable conditions for the development of these crustacean groups, which could be used in environmental monitoring programs and / or be exploited for the aquarium trade.
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The composition and seasonal variation of brachyuran and anomuran species associated with mussel farms were evaluated at Praia da Cocanha, São Paulo between May 2007 and February 2008. Nine mussel ropes were sampled at random in each quarter, and 1,208 organisms were identified, comprising five families and 28 species. The most numerous species was the porcellanid Pachycheles laevidactylus (18.5%), followed by the xanthids Acantholobulus schmitti (16.6%), Hexapanopeus paulensis (11.3%), Panopeus americanus (10.2%), and Menippe nodifrons (8.4%). The exotic crab Charybdis hellerii was recorded throughout the study period. The ecological descriptors, except Pielou evenness index, varied significantly over the time. The highest abundance and diversity of the species were recorded during November and February. This pattern was reversed for Berger-Parker dominance, with the lowest values recorded in February. The development of epifauna was correlated with the different stages of the mussel farms, since the mean size of mussels and consequently the abundance of epibiotic organisms and the structural complexity on the mussel ropes increased from May (seeding) until February (harvest). Despite this, the temporal population variations in recruitment patterns of the different epibionts should not be overlooked. The results indicated that the mussel farms provided favorable conditions for the development of these crustacean groups, which could be used in environmental monitoring programs and / or be exploited for the aquarium trade.
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Centro de Biodiversidad y Gestión Ambiental, Facultad de Ciencias del Mar, Universidad de Las Palmas de Gran Canaria, Las Palmas, Spain
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[EN] Since the industrial revolution, anthropogenic CO2 emissions have caused ocean acidification, which particularly affects calcified organisms. Given the fan-like calcified fronds of the brown alga Padina pavonica, we evaluated the acute (shortterm) effects of a sudden pH drop due to a submarine volcanic eruption (October 2011–early March 2012) affecting offshore waters around El Hierro Island (Canary Islands, Spain). We further studied the chronic (long-term) effects of the continuous decrease in pH in the last decades around the Canarian waters. In both the observational and retrospective studies (using herbarium collections of P. pavonica thalli from the overall Canarian Archipelago), the percent of surface calcium carbonate coverage of P. pavonica thalli were contrasted with oceanographic data collected either in situ (volcanic eruption event) or from the ESTOC marine observatory data series (herbarium study). Results showed that this calcified alga is sensitive to acute and chronic environmental pH changes. In both cases, pH changes predicted surface thallus calcification, including a progressive decalcification over the last three decades. This result concurs with previous studies where calcareous organisms decalcify under more acidic conditions. Hence, Padina pavonica can be implemented as a bio-indicator of ocean acidification (at short and long time scales) for monitoring purposes over wide geographic ranges, as this macroalga is affected and thrives (unlike strict calcifiers) under more acidic conditions
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Blue mould caused by Penicillium expansum Link is one of the most destructive rot of pome fruit in all growing areas (Snowdon, 1990; Jones and Aldwinckle, 1991; Tonini,1996) In the past, Penicillium rot has been controlled by fungicide postharvest treatment mainly by thiabendazole (TBZ) and benomyl (Hardenburg and Spalding, 1972), but their intense use produced the appearance of resistant strains with a great reduction of their activity The aims of the present study were to characterize the isolates of Pencillium sp causing blue mold on pear in Italy by physiological and biochemical parameters. In particular differencing also the behavior of isolates to relationship with sensitivity or resistance to TBZ treatments. We have examined the early stage of infection in relation to enzyme activity, local modulation of pH, production of organic acids, and to secondary metabolism of pathogen. The results described here confirm that the majority of P. expansum isolates from pears packing houses are resistant to TBZ, Among the TBZ-resistant isolates scored in this work, different isolates (RR) showed higher percentage of conidial germination on TBZ-amended medium compared to non amended medium. This may indicate a stimulatory effect of TBZ on conidial germination. Therefore TBZ treatments are not only ineffective for controlling P. expansum, but they may also increase the severity of blue mould on fruits. In the absence of fungicide, isolates showed a significant difference for infection severity, R and RR isolates are characterized by higher pathogenic fitness on fruits, producing larger lesions than S isolates. These data are supported by the study with laboratory-induced resistant isolates, which shows the lack of correlation between TBZ resistance and osmotic sensitivity, and highlights the association between TBZ resistance and infection severity (Baraldi et al 2003). Enzymatic screening gave a positive reaction to esterase, urease, pectinase activity, in addition, the pathogen is able to synthesize a complex enzyme act to degrade the main components of the cell wall especially pectin and cellulose. Isolated sensitive and resistant are characterized by a good activity of pectinase, especially from poligactoronase, which, as already reported by several studies (D'hallewin et al, 2004; Prusky et al, 2004), are the basis of degradative process of cell wall. Also, although the measure was minor also highlighted some activities of cellulase, but even note in the production of this kind of cellulase and hemicellulase P. Expansum were not targeted, studies have found no other source of information in this regard. Twenty isolates of Penicillium expansum, were tested in vitro ad in vivo for acid production ability and pH drop. We have found that modulation of pH and the organic acids extrusion were influence to various parameter: Initial pH: in general, the greatest reduction of pH was observed in isolates grown at pH 7, except for four isolates that maintained the pH of the medium close to 7, the others significantly decreased the pH, ranging from 5.5 to 4.1.. In extreme acid condition (pH 3,0) growth and modulation of pH is most lower respect optimal condition (pH 5,0). Also isolates R and RR have showed a greater adaptation to environmental condition more than isolates S. Time: although the acidification continues for some days, PH modulation is strongest in early hours (48-72 hours)of inoculation process. Time also affects the quality of organic acids, for example in vitro results showed an initial abundant production of succinc acid, followed to important production of galacturoinc acid. Substrates: there are many differences for the type of acids produced in vitro and in vivo. Results showed in vivo an abundant production of galacturonic, malic, and citric acids and some unknown organic acids in smaller concentrations. Secondary metabolite analysis revealed intra-specific differences, and patulin was found in all isolates, but most significant reduction was observed between in vitro and in vivo samples. There was no correlation between the concentration of patulin, and the percentage of infected fruits, but sample with a lower infection severity of rotten area than the others, showed a significantly lower mycotoxin concentration than samples with a higher lesion diameter of rotten area. Beyond of patulin was detected the presence of another secondary metabolite, penitrem A.
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Nonostante lo sforzo sempre crescente mirato allo studio delle malattie che colpiscono le sclerattinie, ancora poco si sa circa distribuzione, prevalenza, host range e fattori che concorrono alla comparsa di queste patologie, soprattutto nell’area indopacifica. Questo studio si propone quindi lo scopo di documentare la presenza della Brown Band Disease all’interno delle scogliere madreporiche dell’Arcipelago delle Maldive. Nell’arco di tempo tra Novembre e Dicembre 2013 è stata effettuata una valutazione di tipo quantitativo di tale patologia su tre isole appartenenti l’Atollo di Faafu, rispettivamente Magoodhoo, Filitheyo e Adangau. Queste tre isole sono caratterizzate da un diverso sfruttamento da parte dell’uomo: la prima isola è abitata da locali, la seconda caratterizzata dalla presenza di un resort e l’ultima, un’isola deserta. Al fine di valutare prevalenza, distribuzione e host range della BrBD sono stati effettuati belt transect (25x2 m), point intercept transect e analisi chimico fisiche delle acque. La Brown Band Disease è risultata essere diffusa tra le isole con prevalenze inferiori al 0,50%. Queste non hanno mostrato differenze significative tra le isole, facendo quindi ipotizzare che i diversi valori osservati potrebbero essere imputati a variazioni casuali e naturali. In tutta l’area investigata, le stazioni più profonde hanno mostrato valori di prevalenza maggiori. La patologia è stata registrata infestare soprattutto il genere Acropora (con prevalenza media totale inferiore all’1%) e in un solo caso il genere Isopora. È stato dimostrato come sia presente una correlazione negativa tra densità totale delle sclerattinie e la prevalenza della Brown Band sul genere Acropora. É stato inoltre notato come vi fosse una correlazione positiva tra la prevalenza della BrBD e la presenza del gasteropode Drupella sulle colonie già malate. Poiché il principale ospite della patologia è anche il più abbondante nelle scogliere madreporiche maldiviane, si rendono necessari ulteriori accertamenti e monitoraggi futuri della BrBD.