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Moura RS Ferreira TS Lopes AA Pires KM Nesi RT Resende AC Souza PJ Silva AJ Borges RM Porto LC Valenca SS 《Phytomedicine》2012,19(3-4):262-269
Short term inhalation of cigarette smoke (CS) induces significant lung inflammation due to an imbalance of oxidant/antioxidant mechanisms. A?ai fruit (Euterpe oleracea) has significant antioxidant and anti-inflammatory actions. The present study aimed to determine whether oral administration of an a?ai stone extract (ASE) could reduce lung inflammation induced by CS. Thirty C57BL/6 mice were assigned to three groups (n=10 each): the Control+A group was exposed to ambient air and treated orally with ASE 300 mg/kg/day; the CS group was exposed to smoke from 6 cigarettes per day for 5 days; and the CS+A group was exposed to smoke from 6 cigarettes per day for 5 days and treated orally with ASE (300 mg/kg/day). On day 6, all mice were sacrificed. After bronchoalveolar lavage, the lungs were removed for histological and biochemical analyses. The CS group exhibited increases in alveolar macrophage (AMs) and neutrophil numbers (PMNs), myeloperoxidase (MPO), superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase activities (GPx), TNF-α expression, and nitrites levels in lung tissue when compared with the control ones (p<0.001 for all parameters). The AMs, PMNs, MPO, SOD, CAT, GPx and nitrite were significantly reduced by oral administration of ASE when compared with CS group (p<0.001 for all parameters, with exception of AMs p<0.01). The present results suggested that systemic administration of an ASE extract could reduce the inflammatory and oxidant actions of CS. Thus, the results of this study in mice should stimulate future studies on ASE as a potential agent to protect against CS-induced inflammation in humans. 相似文献
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By using the proton microprobe technique we have investigated the elemental composition of both pancreatic -cells and exocrine pancreas from fed and 24 h or 48 h starved obese hyperglycemic mice. Among the 15 elements measured in the -cells both Ca and Fe increased while Mg and S decreased significantly after 24 h of starvation, the effects being more pronounced after 48 h. When animals were starved for 48 h there was a decrease in the contents of Cl, Rb and Cu, whereas that of Al and Mn increased with 152 and 55%, respectively. There was an initial decrease in Na after 24 h of starvation, which was followed by an increase after 48 h. This is in contrast to Cd, which first increased and then decreased to a value lower than that obtained in the fed animal. The content of K showed a small decrease and that of Pb showed an increase only in the 24 h starved group. In the -cells the contents of Zn and P did not change subsequent to starvation. In the exocrine pancreas Na, Cl and P decreased after 24 h of starvation and except for Na, the decrease was maintained when the starvation period was increased to 48 h. After 24 h there was a significant, though transient, increase in K, Mg and Rb. With regard to the contents of Zn, Cu and S there was a progressive decrease as the starvation continued. In contrast to the endocrine pancreas the content of Al in the exocrine pancreas did not change after 48 h of starvation. There was no change in islet insulin content subsequent to starvation. The extent to which the observed changes in -cell elemental composition is involved in the impaired insulin release associated with starvation, merits further investigations. 相似文献
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Riparian forests and environments close to watercourses support high biodiversity, which may be modified by human activities. In the Paraná River Delta region, cattle raising is one of the activities with the greatest impact, altering vegetation structure. These changes are reflected in bird communities that inhabit these environments. We hypothesize that the absence of large herbivores (whether cows or native deer) will produce an increase in the vegetation cover of the lower strata of forests, due to the greater height of the herbaceous stratum and greater coverage of the shrub stratum, and that these changes mainly affect the species of birds that use resources associated with these strata. Our objective was to understand the changes in richness and abundance of the bird community among different types of cattle management using a functional aggregation approach of bird species. In the areas with cattle, we found less coverage of the shrub layer, lower height of the herbaceous layer and fewer climbing vines. We found that changes in richness and abundance of bird community were strongly related to species associated with the lower vegetation strata (ground-feeding guild, shrub guild and low canopy guild), and that the responses of the different guilds were not homogeneous. Understanding the direction of changes in bird communities occurring in response to modifications of the environment, allows us to optimize conservation efforts. If these efforts are based on conservation of the environment in its natural state, we should adjust the management of the herbivory to the pristine conditions of the environment. On the other hand, if conservation efforts are based on particular species or groups of species associated with certain resources, the correct management of herbivory by cattle can be essential to obtain successful results. 相似文献
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Six trees of the palm species Attalea phalerata Mart. were sampled during high water (aquatic phase) of the Pantanal of Mato Grosso (February 2001), by canopy fogging. The composition, structure, and biomass of the arthropod community associated with their canopies were analysed, as well as the influence the flood pulse renders on it. Each tree was fogged once, followed by three consecutive collections. A total of 63,657 arthropods (643.0 +/-; 259.87 ind./m(2)) were collected, representing 25 orders in the classes Insecta, Arachnida, Diplopoda and Crustacea. The dominant groups were Acari (40.0%; 257.2 +/- 116.50 ind./m(2)), Coleoptera (12.0%; 77.5 +/- 64.93 ind./m(2)), Psocoptera (9.2%; 59.0 +/- 38.00 ind./m(2)), Diptera (8.4%; 54.1 +/- 18.72 ind./m(2)), Collembola (8.3%; 53.4 +/- 26.24 ind./m(2)) and Hymenoptera (7.9%; 50.6 +/- 21.40 ind./m(2)), the latter mostly represented by Formicidae (49.2%). Arthropod biomass amounted to 8.86 g dry weight and 0.18 mg/m(2). Coleoptera, Blattodea, Orthoptera, Araneae and Hymenoptera were the most representative taxa. The hydrological regime (flood pulse), as well as seasonality, appear to strongly affect the composition and structure of this canopy community. 相似文献
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Jonny Everson Scherwinski-Pereira Rodrigo da Silva Guedes Ricardo Alexandre da Silva Paulo César Poeta FerminoJr. Zanderluce Gomes Luis Elínea de Oliveira Freitas 《Plant Cell, Tissue and Organ Culture》2012,109(3):501-508
An efficient and simple system for inducing somatic embryogenesis and regenerating plantlets from immature zygotic embryos of açaí palm (Euterpe oleracea) has been developed. Embryogenic calli (ECs) were induced from immature zygotic embryos of açaí palm on Murashige and Skoog (MS) modified medium with 2,4-dichlorophenoxyacetic acid and picloram. Embryogenic frequency was dependent on auxin type and concentration. The optimal concentration of picloram for the high-frequency induction of embryogenic calli (72%) was 225 μM. ECs were then subcultured on a differentiation and maturation medium composed of MS modified medium with 2-isopentenyladenine and naphthaleneacetic acid with subcultures at 4-week intervals. SEs were converted to plants on MS modified medium with half-strength macro- and micronutrients, 20 g l?1 sucrose, and 2.5 g l?1 activated charcoal and gelled with 2.5 g l?1 Phytagel. Detailed morpho anatomical changes during the different stages of somatic embryogenesis were characterized. The development of SEs was asynchronous, and ontogenic studies confirmed that the initial cell divisions occur in the epidermal and subepidermal regions of the zygotic embryos. Broad base attachment of SEs to the epidermis indicates the presence of a suspensor. 相似文献
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Annona crassiflora Mart., whose fruit is popularly known as araticum, is a member of the Annonaceae family found in the Brazilian Cerrado. Although this plant has several medicinal uses, its bioactive molecules are not fully understood. A bioguided assay was performed to identify the main bioactive compounds of A. crassiflora fruit peel from the ethanol extract fractions with antioxidant capacity and α-amylase, α-glucosidase and glycation inhibitory activities. Ethyl acetate and n-butanol fractions showed, respectively, higher antioxidant capacity (DPPH IC50 1.5 ± 0.1 and 0.8 ± 0.1 μg mL−1, ORAC 3355 ± 164 and 2714 ± 79 μmol trolox eq/g, and FRAP 888 ± 16 and 921 ± 9 μmol trolox eq/g) and inhibitory activities against α-amylase (IC50 4.5 ± 0.8 and 1.7 ± 0.3 μg mL−1), α-glucosidase (IC50 554.5 ± 158.6 and 787.8 ± 140.6 μg mL−1) and glycation (IC50 14.3 ± 3.3 and 16.0 ± 4.2 μg mL−1), and lower cytotoxicity, compared to the other fractions and crude ethanol extract. The HPLC-ESI-MS/MS analysis identified various biomolecules known as potent antioxidants, such as chlorogenic acid, (epi)catechin, procyanidins, caffeoyl-hexosides, quercetin-glucosides and kaempferol. The fruit peel of A. crassiflora, a specie from Cerrado, the Brazilian Savanna, provided a source of antioxidant compounds with properties to block carbohydrate digestive enzymes and formation of glycation products. Thus, there is potential to use the by-products of araticum in order to identify and isolate phytochemicals for application in nutraceutical supplements, food additives and pharmaceuticals products. 相似文献
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The zinc biosorptive capacity of the brown seaweed Sargassum sp. (Phaeophyceae) was studied in the presence or absence of competing calcium ions, using a continuous system with tubular fixed-bed reactors. In order to detect the effect of calcium on zinc biosorption, a 130 mg/l zinc solution was used, and calcium was added at 50-340 mg/l. The potential zinc biosorptive capacity of the biomass was markedly influenced by the presence of ionic calcium. Zinc sorption decreased with increasing calcium concentrations, as expressed by zinc uptake rates. Calcium was effectively recovered only during the initial stages of the process, as expressed by the decrease in its uptake rates. Calcium uptake rates were also much higher than zinc uptake rates, indicating that calcium was preferentially recovered when compared to zinc. 相似文献
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J. M. Daly S. M. Evans Janet Morley 《Marine and Freshwater Behaviour and Physiology》2013,45(1-4):49-69
Spacing between individuals in populations of Harmothoë imbricata has been investigated both on the shore and in the laboratory. Males tend to occur closer together than females, and the mean male‐male individual distance measured was less than the mean distance between females; male—female distances for immature worms were intermediate. When worms mature they pair: the male mounts the female and lies across her dorsal surface. There is evidence that after spawning the members of a pair separate. Contact responses between worms have been investigated in the laboratory. Most encounters between immature worms lead to separation, as a result of one or both worms moving rapidly away from the other or fighting; females show more marked avoidance behaviour than males. The majority of male‐male and female‐female encounters between mature worms also lead to separation but in male‐female encounters the male usually mounts the female. A male which has mounted a female becomes highly aggressive and will attack intruding males but not females. 相似文献
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M E Tischler 《The Biochemical journal》1980,192(3):963-966
In isolated rat diaphragms, only those substrates that increased the tissue NADH/NAD+ ratio lowered the rate of proteolysis. However, direct inhibition of proteinase activity by leupeptin promoted oxidation of the NAD couple of the muscles. These results suggest that changes in muscle reduction-oxidation state may be important in the regulation of proteolysis. 相似文献
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The present report deals with the structural abnormalities and abortion of the endosperm, and the related abnormal development of the embryos in the intergeneric crosses of radish (Raphanus sativus L.) ♀ with cabbage (Brassica oleracea L.) ♂. The weak development of ER, the occurence of starch grains in chloroplasts, the curious distribution of chloroplasts around the nuclei, and the earlier formation of cellular endosperm are some primary structure abnormalities of endosperm and they may indicate the poor development, low metabolic activities, and precocious growth in the hybrid endosperm. The endosperm abortion, which starts from chalazal end endosperm, comprises the damage of both structure and function of ER membrane, and the disintegration of nuclei and organelles, or even death. The hybrid embryos degenerated very early in 2-cell stage or even zygote stage in case the endosperm Aborted early. In case of endosperm late-aborted, the hybrid embryos grew for quite a long period of time but become slow down as the endosperm showed abnormal development and started to abort. As the results, the embryos were smaller, the embryo propers and the suspensors showed no growth in step with one another, and the embryo cells appeared structural abnormalities, and finally degenerated and aborted. 相似文献
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Jun Wu Chao Gu Yu-Hu Du Hua-Qing Wu Wei-Sheng Liu Ning Liu Juan Lu Shao-Ling Zhang 《Sexual plant reproduction》2011,24(1):23-35
Apricot (Prunus armeniaca L.) cultivars originated in China display a typical S-RNase-based gametophytic self-incompatibility (GSI). ‘Katy’, a natural self-compatible cultivar belonging to the European ecotype
group, was used as a useful material for breeding new cultivars with high frequency of self-compatibility by hybridizing with
Chinese native cultivars. In this work, the pollen-S genes (S-haplotype-specific F-box gene, or SFB gene) of ‘Katy’ were first identified as SFB
1 and SFB
8, and the S-genotype was determined as S
1
S
8. Genetic analysis of ‘Katy’ progenies under controlled pollination revealed that the stylar S1-RNase and S8-RNase have a normal function in rejecting wild-type pollen with the same S-haplotype, while the pollen grains carrying either
the SFB
1 or the SFB
8 gene are both able to overcome the incompatibility barrier. However, the observed segregation ratios of the S-genotype did
not fit the expected ratios under the assumption that the pollen-part mutations are linked to the S-locus. Moreover, alterations in the SFB
1 and SFB
8 genes and pollen-S duplications were not detected. These results indicated that the breakdown of SI in ‘Katy’ occurred in pollen, and other
factors not linked to the S-locus, which caused a loss of pollen S-activity. These findings support a hypothesis that modifying factors other than the S-locus are required for GSI in apricot. 相似文献
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A study was made of the day-night changes under controlled environmental conditions in the bulk-leaf water relations of Kalanchoë daigremontiana, a plant showing Crassulacean acid metabolism. In addition to nocturnal stomatal opening and net CO2 uptake, the leaves of well-watered plants showed high rates of gas exchange during the whole of the second part of the light period. Measurements with the pressure chamber showed that xylem tension increased during the night and then decreased towards a minimum at about midday; a significant increase in xylem tension was also seen in the late afternoon. Cell-sap osmotic pressure paralleled leaf malate content and was maximum at dawn and minimum at dusk. The relationship between these two variables indicated that the nocturnally synthesized malate was apparently behaving as an ideal osmoticum. To estimate bulk-leaf turgor pressure, values for water potential were derived by correcting the pressurechamber readings for the osmotic pressure of the xylem sap. This itself was found to depend on the malate content of the leaves. Bulk-leaf turgor pressure changed rhythmically during the day-night cycle; turgor was low during the late afternoon and for most of the night, but increased quickly to a maximum of 0.20 MPa around midday. In water-stressed plants, where net CO2 uptake was restricted to the dark period, there was also an increase in bulk-leaf turgor pressure at the start of the light period, but of reduced magnitude. Such changes in turgor pressure are likely to be of considerable ecological importance for the water economy of crassulacean-acid-metabolism plants growing in their natural habitats.Abbreviation and symbols CAM
Crassulacean acid metabolism
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P
turgor pressure
-
osmotic pressure
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water potential
Dedicated to Professor Dr. H. Ziegler on the occasion of his 60th birthday 相似文献
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The 7S globulin, a major ultracentrifugal component with the 11S globulin, was identical with β-conglycinin one of four antigenic components in the reserve proteins of soybean seeds (Glycine max). Double gel immunodiffusion and immunoelectrophoresis in agar gel were used for their identification. In addition, some characteristic properties on ultracentrifugation and in carbohydrate content agreed well between the proteins. Their MWs were ca 180000. 相似文献
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Summary Phagocytosis ofNostoc filaments byGeosiphon, a fungus closely related to AM forming Glomales, was observed under light microscopes. Incorporation can only be performed ifNostoc primordia come into contact with growing hyphal tips of the fungus. The fungal wall just below the apex softens, and fungal cytoplasm is bulged out repeatedly covering the vegetativeNostoc cells but not the heterocytes. New heterocytes are differentiated by the internalised filament whose cells can increase up to ten times in volume after recovering from incorporation strain. TheNostoc cells are coated stepwise by short finger-shaped protuberances of the fungal hypha. These hernia-like outgrowths first remain separated, after 1 to 2 days they merge. Adjacent hyphal walls inside the complex covering disintegrate. Periphal fungal wall portions are united to form a smooth strong outer envelope. Internalisation is categorised as phagocytosis. The partnership is partly specific,Nostoc strains capable of living endocytobiotically are often partners in other symbioses besidesGeosiphon.Abbreviations AM
arbuscular mycorrhiza (formerly VAM vesicular arbuscular mycorrhiza)
- DIC
differential interference contrast
- LD
light/dark
Dedicated to Prof. Dr. Dr. h.c. Eberhard Schnepf on the occasion of his retirement 相似文献
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Peptide patterns and immunological properties of the cytoplasmic and chloroplastic -1,4-glucan phosphorylase (EC 2.4.1.1) from spinach leaves have been studied and were compared with those of phosphorylases from other sources. The two spinach leaf phosphorylases were immunologically different; a limited cross-reactivity was observed only at high antigen or antibody concentrations. Peptide mapping of the two enzymes resulted in complex patterns composed of more than 20 fragments; but no peptide was electrophoretically identical in both proteins. Approximately 13 to 15 of the fragments exhibited antigeneity but no cross-reactivity of any peptide was observed. Therefore, the two compartment-specific phosphorylase forms from spinach leaves represent isoenzymes possessing different primary structures. Peptide patterns of potato tuber and rabbit muscle phosphorylase were different from those of the two spinach leaf enzymes. Although the potato tuber phosphorylase resides in the plastidic compartment and is kinetically closely related to the chloroplastic spinach enzyme, it reacted more strongly with the anti-cytoplasmic-phosphorylase immunoglobulin G. Similar results were obtained with rabbit muscle phosphorylase. These observations support the assumption that the chloroplast-specific phosphorylase isoenzyme has a higher structural diversity than does the cytoplasmic counterpart.Abbreviations EDTA
ethylenediaminetetraacetic acid
- Hepes
4-(2-hydroxyethyl)-1-piperazineethanesulfonic acid
- PEG
polyethylene glycol (approx. MW 8000)
I=Schächtele and Steup 1986 相似文献
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Long-term development of the crustacean plankton in the Saidenbach Reservoir (Germany) – changes,causes, consequences 总被引:3,自引:0,他引:3
The rates of development and food intake of the copepod Temora longicornis (Müller) were studied using artificial blooms of Phaeocystis globosa Scherffel under different conditions of nutrient limitation. Mesocosms with 800 l of natural seawater were manipulated by inoculation with cultured P. globosa and by addition of nitrogen and/or phosphorus, to obtain N- or P-limited blooms of P. globosa. During development and ageing of these blooms, water from the mesocosms was used as medium for incubation of nauplii of T. longicornis. Only moderate rates of naupliar development as well as high rates of mortality were observed, irrespective of major differences of nutrient conditions and density of P. globosa. Grazing by the nauplii on P. globosa seemed to be low, suggesting a low food quality of this alga at all physiological conditions studied. The results of this study indicate a low capability of T. longicornis nauplii for control of nuisance algal blooms caused by P. globosa. 相似文献
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Yingnan Huang Hao Wu Ruyi Xue Taotao Liu Ling Dong Jun Yao Yang Zhang Xizhong Shen 《PloS one》2013,8(10)