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Type 2 diabetes mellitus contributes to an increased risk of metabolic and morphological changes in key organs, such as the liver. We aimed to assess the effect of the açaí seed extract (ASE) associated with exercise training on hepatic steatosis induced by high-fat (HF) diet plus streptozotocin (STZ) in rats. Type 2 diabetes was induced by feeding rats with HF diet (55% fat) for 5 weeks, followed by a single low dose of STZ (35 mg/kg i.p.). Control and diabetic groups were subdivided into four groups that were fed with standard chow diet for 4 weeks. Control (C) group was subdivided into Sedentary C, Training C, ASE Sedentary C and ASE Training C. Diabetic (D) group was subdivided into Sedentary D, Training D, ASE Sedentary D and ASE Training D. ASE (200 mg/kg/day) was administered by intragastric gavage, and the exercise training was performed on a treadmill (30 min/day; 5 days/week). Treatment with ASE associated with exercise training reduced the blood glucose (70.2%), total cholesterol (81.2%), aspartate aminotransferase (51.7%) and hepatic triglyceride levels (66.8%) and steatosis (72%) in ASE Training D group compared with the Sedentary D group. ASE associated with exercise training reduced the hepatic lipogenic proteins’ expression (77.3%) and increased the antioxidant defense (63.1%), pAMPK expression (70.2%), cholesterol transporters (71.1%) and the pLKB1/LKB1 ratio (57.1%) in type 2 diabetic rats. In conclusion, ASE treatment associated with exercise training protects against hepatic steatosis in diabetic rats by reducing hepatic lipogenesis and increasing antioxidant defense and cholesterol excretion.  相似文献   

3.
Açai, the fruit of a palm native to the Amazonian basin, is widely distributed in northern South America, where it has considerable economic importance. Whereas individual polyphenolics compounds in açai have been extensively evaluated, studies of the intact fruit and its biological properties are lacking. Therefore, the present study was undertaken to investigate the in vivo genotoxicity of açai and its possible antigenotoxicity on doxorubicin (DXR)-induced DNA damage. The açai pulp doses selected were 3.33, 10.0 and 16.67 g/kg b.w. administered by gavage alone or prior to DXR (16 mg/kg b.w.) administered by intraperitoneal injection. Swiss albino mice were distributed in eight groups for acute treatment with açai pulp (24 h) and eight groups for subacute treatment (daily for 14 consecutive days) before euthanasia. The negative control groups were treated in a similar way. The results of chemical analysis suggested the presence of carotenoids, anthocyanins, phenolic, and flavonoids in açai pulp. The endpoints analyzed were micronucleus induction in bone marrow and peripheral blood cells polychromatic erythrocytes, and DNA damage in peripheral blood, liver and kidney cells assessed using the alkaline (pH >13) comet assay. There were no statistically significant differences (p > 0.05) between the negative control and the groups treated with the three doses of açai pulp alone in all endpoints analyzed, demonstrating the absence of genotoxic effects. The protective effects of açai pulp were observed in both acute and subacute treatments, when administered prior to DXR. In general, subacute treatment provided greater efficiency in protecting against DXR-induced DNA damage in liver and kidney cells. These protective effects can be explained as the result of the phytochemicals present in açai pulp. These results will be applied to the developmental of food with functional characteristics, as well as to explore the characteristics of açai as a health promoter.  相似文献   

4.
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   

5.
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   

6.
M-mode echocardiograms were obtained on unmedicated males with mild hypertension before and after treatment with thermal biofeedback, autogenic training, or self-relaxation. Although patients for whom diastolic blood pressure (DBP) was successfully reduced showed trends toward reduction in left ventricular parameters while unsuccessful patients showed no changes, the results were not significant. For the four patients with borderline left ventricular hypertrophy, there was a strong trend (p = .06) for successful treatment to lead to a reduction in left ventricular mass. Moreover, across the whole sample, reduction in left ventricular mass was related (r = .30) to decrease in DBP.  相似文献   

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M-mode echocardiograms were obtained on unmedicated males with mild hypertension before and after treatment with thermal biofeedback, autogenic training, or self-relaxation. Although patients for whom diastolic blood pressure (DBP) was successfully reduced showed trends toward reduction in left ventricular parameters while unsuccessful patients showed no changes, the results were not significant. For the four patients with borderline left ventricular hypertrophy, there was a strong trend (p=.06) for successful treatment to lead to a reduction in left ventricular mass. Moreover, across the whole sample, reduction in left ventricular mass was related (r=.30) to decrease in DBP.This research was supported by a grant from the NHLBI, HL-31189.  相似文献   

9.
Magnetic resonance imaging remains the only non-invasive method to assess the quality of cartilage repair procedures, but ideally would be complemented by other modalities, particularly blood tests. Nganvongpanit and colleagues investigated serum levels of hyaluronic acid (HA) and chondroitin sulfate (CS) for their correlation with tissue quality after cartilage repair with autologous chondrocytes versus subchondral drilling in a dog model. They reported better tissue quality in animals treated with chondrocyte implantation. Serum levels correlated with the histological score of biopsy samples: CS showed a negative (r = -0.69) and HA a positive (r = +0.46) correlation. Many questions remain to be answered before serum markers can provide a reliable, non-invasive tool to assess tissue quality, but these data provide an important foundation for additional research.  相似文献   

10.
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   

11.
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   

12.
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   

13.
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   

14.
For many organisms the ability to cold acclimate with the onset of seasonal cold has major implications for their fitness. In insects, where this ability is widespread, the physiological changes associated with increased cold tolerance have been well studied. Despite this, little work has been done to trace changes in gene expression during cold acclimation that lead to an increase in cold tolerance. We used an RNA-Seq approach to investigate this in two species of the Drosophila virilis group. We found that the majority of genes that are differentially expressed during cold acclimation differ between the two species. Despite this, the biological processes associated with the differentially expressed genes were broadly similar in the two species. These included: metabolism, cell membrane composition, and circadian rhythms, which are largely consistent with previous work on cold acclimation/cold tolerance. In addition, we also found evidence of the involvement of the rhodopsin pathway in cold acclimation, a pathway that has been recently linked to thermotaxis. Interestingly, we found no evidence of differential expression of stress genes implying that long-term cold acclimation and short-term stress response may have a different physiological basis.  相似文献   

15.
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   

16.
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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18.
The productivity of water hyacinth in the middle Paraná River was measured at three initial biomass levels by means of periodic harvesting of plants contained in 2 m2 floating baskets. The measuring period extended between August 1981 and July 1982. Initial biomass densities were 2, 5 and 10 kg (fw) m–2.Compared with inner island ponds, flowing waters connected to the main river showed better conditions for water hyacinth growth. The duration of the growth period was some 30% longer than in island ponds, probably due to the relatively warmer river waters. Productivity ranged between 108 and 164 g (fw) m –2 d–1 (annual average) for the lower and higher initial biomass values, respectively.  相似文献   

19.
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   

20.
This paper studies the genetic importance of growth curve parameters and their relevance as selection criteria in breeding programmes of Segureño sheep. Logistic and Verhulst growth functions were chosen for their best fit to BW/age in this breed; the first showed the best general fit and the second the best individual fit. Live weights of 41 330 individuals from the historical archives of the National Association of Segureña Sheep Breeders were used in the analysis. The progeny of 1464 rams and 27 048 ewes were used to study the genetic and phenotypic parameters of growth curve parameters and derived traits. Reproductive management in the population consists in controlled natural mating inside every herd, with a minimum of 15% of the females fertilized by artificial insemination with fresh semen; with the purpose being the herd genetic connections, all herd genealogies are screened with DNA markers. Estimates of growth curve parameters from birth to 80 days were obtained for each individual and each function by the non-linear regression procedure using IBM SPSS statistics (version 21) with the Levenberg–Marquart estimation method. (Co)variance components and genetic parameters were estimated by using the REML/Animal model methodology. The heritability of mature weight was estimated as 0.41±0.042 and 0.38±0.021 with the logistic and Verhulst models, respectively, and the heritability of other parameters ranged from 0.41 to 0.62 and 0.37 to 0.61, with the models, respectively. A negative genetic correlation between mature weight and rate of maturing was found.  相似文献   

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