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1.
Streptozotocin destroys the beta-cells of pancreas by generation of reactive oxygen species and vitamin E has documented antioxidant properties. To evaluate the preventive effect of vitamin E on induction of diabetes by streptozotocin and effect of oral vitamin E consumption on carbohydrate and lipid metabolism, forty male Wistar rats divided randomly to control, E1, E2 and E3 groups. The diet of E1, E2 and E3 groups were supplemented with 1, 2 and 4 g kg(-1) of vitamin E, respectively. Four days later all rats were made diabetic by IP injection of 45 mg kg-' streptozotocin and blood glucose was measured 72 h later to determine the severity of blood glucose elevation. Glycosylated hemoglobin, triglyceride, total cholesterol and HDL-c were measured and LDL-c and VIDL-c calculated in plasma of 6 diabetic rats with glucose more than 200 mg dL(-1) in each groups 21 days after streptozotocin injection. Vitamin E had no effect on diabetes induction by streptozotocin, but elevation of glycosylated Hb and reduction of LDL-c in group E3 were significant. Vitamin E also increased HDL-c although it was not statistically significant. We suggest that oral vitamin E consumption may have some beneficial effect on the correction of lipid metabolism disorders of diabetes, although it may worsen carbohydrate metabolism in mild diabetes.  相似文献   

2.
Summary Functional female fertility (FFF) and functional male fertility (FMF) were studied in diploid potato clones, includingS. tuberosum haploids, F1 hybrids between haploids and otherSolanum species, and in progenies from subsequent hybridisations. The results of 402 crosses between 91 diploid potato clones revealed that 60% of all genotypes had low levels of FFF as well as low levels of FMF regardless of their origin and degree of hybridity. Failed crosses (without any fruits at all) and those with a low level of success (with less than 3 seeds per pollinated flower) constituted 69% of all studied crosses. Most of these had resulted from parents with low levels of FFF and FMF, and these two characteristics were expressed independently. Functional female fertility affected crossability behaviour no less than FMF, therefore both FFF and FMF should be controlled in diploid potato clones involved in breeding. Reliable FFF and FMF estimates can be based only on crossing results. The coefficient of multiple correlation between seeds per pollinated flower in crosses and FFF and FMF estimates of the parental clones was 0.80 (P<0.01). Hence the compilation and analysis of the results of diploid potato crosses allow a reliable assessment of FFF and FMF and consequently the prediction of crossability with a degree of sufficient accuracy.  相似文献   

3.
It was found that exogenous ethylene or ethrel could induce rice male sterility and endogenous ethylene was negatively correlated with pollen fertility and play a key role in the occurrence of rice male sterility. However, it is unknown whether ethylene is related to the occurrence of CMS (cytoplasmic male sterility). In this study, a field experiment was conducted in Guangzhou, using CMS line Zhenshan 97A and its maintainer line Zhenshan 97B.  相似文献   

4.
Background. The major side effect of cisplatin, used in some tumours, is nephrotoxicity. Reactive oxygen species and oxidative damage are the most important factors in cisplatin-induced acute renal failure. The main purpose of this study is to investigate the protective effects of crocin against cisplatin-induced acute renal failure and oxidative stress in rat. Methods. In this study, animals were randomly divided into 5 groups (6 each). Group one received normal saline (2 ml/day, i.p.). Group two received a single dose of cisplatin (5 mg/kg, i.p.). Groups 3 to 5 received crocin (100, 200 and 400 mg/kg, i.p., respectively, for 4 consecutive days one hour before a single dose of cisplatin (5 mg/kg) only at the first day. Blood samples were taken out (on the fifth day) for measuring the level of urea and creatinine. The kidneys were removed for histopathological and biochemical examinations. Furthermore, 24-hour urinary factors were measured. Results. Blood urea, creatinine and urinary glucose and protein concentrations in crocin-treated groups were significantly lower than those of cisplatin-treated group in a dose-dependent manner. Histopathological studies showed a massive damage in S3 segment of proximal tubules in cisplatin-treated group. No damage was observed in crocin-treated groups. Crocin treatment resulted in a significant and dose-dependent reduction in malondialdehyde concentration as compared to the cisplatin-treated group. Moreover, crocin produced a significant elevation in total thiol and glutathione peroxidase concentrations, as compared with cisplatin-treated group. Conclusion. The results of the present study suggest that crocin has a protective effect against cisplatin-induced acute renal failure and relative oxidative stress.  相似文献   

5.

Background  

Many physiological processes of mammalian species exhibit daily rhythmicity. An intrinsic relationship exists between fat soluble vitamins (A, D, E and K) and several body functions. Few investigations on the rhythmic pattern of vitamins in domestic animals have been carried out. The present study evaluated the circadian rhythmicity of fat soluble vitamins in the horse.  相似文献   

6.
Vacuum insulation panel (VIP), which is composed of an evacuated core material encapsulated in an envelope and supplemented with a desiccant, is a high performance thermal insulation material. In this paper, thermos-physical properties of chopped fiber, centrifugal-spinneret-blow (CSB) fiber, flame-spinneret-blow (FSB) fiber and hybrid (CSB: FSB=1:1) fiber as fillers of vacuum insulation panel are explored. The results show that the increase of pore size can improve thermal insulation property; fibers distribute in 2-D structure, which can reduce the heat conduction, leads to reduce the thermal conductivity. VIP with chopped fiber has the best thermal insulation, and thermal conductivity is 1.4 mW/m.K. Due to difference of core materials, thermal insulation characteristics of VIP can be divided into three distinct regions based on the internal pressure range, i.e., (I) ≥12000 Pa region, (II) 80-12000 Pa region, (III) ≤ 80 Pa region. It also finds that service life of VIP can be improved by the reducing the pore size of core materials. VIP with different core materials shows different degradation and the degradation rate of VIP with FSB core material is minimum.  相似文献   

7.
BACKGROUND: Teucrium polium is an analgesic, antidiabetic and antilipeidemic herbal medicament. The aim of this survey was to evaluate the effect of aqueous extract T. polium on liver enzymes linked to liver dysfunction, serum lipids and glucose, in diabetic male rats. METHODS: A total of 20 Sprague-Dawly male rats became diabetic by intraperitoneal injection of streptozotocin (60 mg/kg). the animals were divided randomly into two groups. Experimental group was fed Teucrium polium (50 mg/kg) for a month but control group was received the same volume of distilled water. Liver enzymes, biochemical parameters (cholesterol, triglyceride, low density lipoprotein, alanine transaminase, aspartae transaminase) and glucose were measured by kinetic (Enzymatic) and colorimetric methods. Data obtained were analyzed and mean values were compared by paired student's t-test. The results were expressed as mean +/- SD. Significant differences were set at P < 0.05. RESULTS: Our results showed that in test group, serum glucose values decreased significantly (P < 0.05), but cholesterol, triglyceride, low density lipoprotein, alanine transaminase and aspartae transaminase increased significantly after use of T. polium (P < 0.05). This parameters value did not show any changes in control group. CONCLUSION: Although the aqueous extract of Teucrium polium has strong hypoglycemic properties in experimental animals, but because of some hepatotoxic effects, it is not suitable to use it in human as an antidiabetic agent.  相似文献   

8.
The seedlings of indica hybrid rice Weiyou 49 and Weiyou 28 were exposed to 1℃ and 40℃ .and the changes of activity (content) of superoxide dismutase (SOD), catalase (CAT), peroxidase (POX), ascorbic acid (ASA), glutathione (GSH),malondialdehyde (MDA) and leakage of electrolytes (%) were measured.  相似文献   

9.
Iron, as inorganic ion or as oxide, is widely used by biological systems in a myriad of biological functions (e.g., enzymatic, gene activation and/or regulation). In particular, marine organisms containing silica structures—diatoms and sponges—grow preferentially in the presence of iron. Using primary sponge cell culture from S. domuncula–primmorphs—as an in vitro model to study the Demospongiae spiculogenesis, we found the presence of agglomerates 50 nm in diameter exclusively inside sponge specialized cells called sclerocytes. A clear phase/material separation is observed between the agglomerates and the initial stages of intracellular spicule formation. STEM-HRTEM-EDX analysis of the agglomerates (30–100 nm) showed that they are composed of pseudohexagonal nanoparticles between 5 and 15 nm in size, displaying lattice parameters corresponding to hematite (Fe2O3) and mixed iron oxide phases typically attributed to ferritin. Further analysis, using western blotting, inductively coupled plasma mass spectrometry (ICP-MS), sequence alignment analysis, immunostaining and magnetic resonance imaging (MRI), of mature spicule filaments confirm the presence of ferritin within these organic structures. We suggest that S. domuncula can be classified as a dual biomineralizating organism, i.e., within the same cellular structure two distinct biomineralizing processes can occur as a result of the same cellular/metabolic function, spiculogenesis.  相似文献   

10.

Background  

The role of differential selection in determining the geographic distribution of genotypes in hybrid systems has long been discussed, but not settled. The present study aims to asses the importance of selection in structuring all-hybrid Pelophylax esculentus populations. These populations, in which the parental species (P. lessonae with genotype LL and P. ridibundus with genotype RR) are absent, have pond-specific proportions of diploid (LR) and triploid (LLR and LRR) genotypes.  相似文献   

11.
Phytic acid, saponin and polyphenol contents in grains of various varieties of black gram (Vigna mungo) Mung bean (Vigna radiata L.) amphidiploids ranged from 697 to 750, 2746 to 2972 and 702 to 783 mg/100 g, respectively. Domestic processing and cooking methods including soaking, ordinary and pressure cooking of soaked and unsoaked seeds, and sprouting significantly lowered phytic acid, saponin and polyphenol contents of the amphidiploid seeds. Soaking for 18 h removed 31 to 37% of the phytic acid; the extent of removal was higher with long periods of soaking. Saponins and polyphenols were relatively less affected. Loss of the antinutrients was greater when soaked instead of unsoaked seeds were cooked. Pressure cooking had a greater effect than ordinary cooking. Antinutrient concentrations declined following sprouting; the longer the period of germination the greater was the reduction.  相似文献   

12.
To explore the mechanisms of the differences in capacities related to photodamage-resistance of indica and japonica subspecies, the xanthophyll cycle components, violaxanthin (V), antheraxanthin (A), zeaxanthin (Z), PSⅡ-D1-protein contents, and PSⅡ photochemical efficiency (Fv/Fm) were measured in rice leaves pretreated by streptomycin(SM, a PSⅡ-D1-protein inhibitor) and dithiothreitol (DTT, an xanthophyll cycle inhibitor), respectively.  相似文献   

13.
Feeding of raw and heated soy flour (RSF & HSF) for 4 or 8 weeks to weanling swine was compared with feeding of casein diets. There was essentially no growth in pigs fed RSF, whereas body weight increased 4.5 fold over 8 weeks with either casein or HSF. No change in pancrease weight as percent body weight was found in any group in either experiment. Both total pancreatic RNA and DNA were decreased in RSF groups, although RNA and DNA/mg pancreas were increased by the RSF diets. Total pancreatic protein, as well as protein/mg, were decreased in RSF-fed pigs compared to casein and HSF. Pancreatic trypsin, chymotrypsin, lipase, and amylase, and fecal trypsin were decreased in RSF-fed pigs to varying degrees compared to either HSF or casein. HSF and casein performance was equivalent in all parameters measured. Results of these experiments are compared with results of feeding similar diets to rats and monkeys.  相似文献   

14.
Reverse chemical proteomics combines affinity chromatography with phage display and promises to be a powerful new platform technology for the isolation of natural product receptors, facilitating the drug discovery process by rapidly linking biologically active small molecules to their cellular receptors and the receptors’ genes. In this paper we review chemical proteomics and reverse chemical proteomics and show how these techniques can add value to natural products research. We also report on techniques for the derivatisation of polystyrene microtitre plates with cleavable linkers and marine natural products that can be used in chemical proteomics or reverse chemical proteomics. Specifically, we have derivatised polystyrene with palau’amine and used reverse chemical proteomics to try and isolate the human receptors for this potent anticancer marine drug.  相似文献   

15.
Early vigor and rapid canopy development are important characteristics in aerobic rice culture, where they are highly susceptible to soil water deficits. To elucidate the response of rice's vegetative growth to water management regimes, we evaluated the leaf growth and the concomitant nitrogen (N) utilization of nine cultivars grown in flooded and aerobic culture in 2 years. In aerobic culture, the soil water potential at a depth of 20 cm frequently reached −60 kPa in 2007, but remained above −30 kPa in 2008. The average leaf area index (LAI) in the middle of the vegetative growth stage, N uptake and leaf N content per unit leaf area (specific leaf N; SLN) in aerobic culture were comparable to those in flooded culture. However, there was a significant cultivar × water regime interaction in LAI: cultivars with higher LAI during the vegetative growth stage achieved higher yield in aerobic rice culture. IR72 and Takanari (high-yielding cultivars of flood-irrigated rice) showed poor leaf growth as well as lower N uptake and higher SLN in aerobic culture compared with flooded culture. Our results show that early vigor is closely associated with yield stability to the soil moisture fluctuations in aerobic rice culture, even if weeds are properly controlled. Greater N uptake from aerobic soil and better balancing between the N demand for leaf growth and the N supply to the leaves under fluctuating soil moisture would be, at least in part, relevant to a rice cultivar's adaptation to aerobic conditions.  相似文献   

16.
The effects of sward age and fertilizer‐nitrogen (N) application rate on reproductive tillers and their involvement in the dynamics of swards of perennial grasses were investigated using sown swards of tall fescue (Festuca arundinacea). Treatments included plots representing two sward ages (two and six‐year‐old swards) and two fertilizer‐N rates (150 and 350 kg N ha?1 yr?1) on the same experimental field. In each of 2 years all plots were cut at the silage stage and three times afterwards. After each cut, during two growing seasons, the vegetative tillers and stubs of cut reproductive tillers were counted in ten permanent quadrats for each of the four treatments, using a grid of 150 cells, each of 2 cm × 2 cm. The results showed a higher density, and a greater proportion of reproductive tillers, on the higher fertilizer‐N rate treatment and on the older swards. The density of vegetative tillers was found to be greater in close proximity to the reproductive tillers in all sward treatments and in both assessment years. Thus, cutting the reproductive tillers did not result in thinning of the swards. It is suggested that a mother‐tiller effect, enhancing renewal of tillers, was likely, although zones bearing reproductive tillers during the second spring were sometimes already denser than zones in the rest of the quadrats before the winter.  相似文献   

17.
《Plant Production Science》2013,16(4):223-226
Abstract

In a rice panicle, the superior spikelets display higher growth rates than the inferior spikelets during the initial phase of grain-filling. To better understand the regulatory mechanism of this phenomenon, we examined the dynamics of endogenous abscisic-acid (ABA) levels and the effects of shading on the dynamics during the grain-filling period in superior and inferior spikelets. While ABA content in the superior spikelets increased rapidly after flowering, that in the inferior spikelets increased slowly and reached the maximum later than in the superior spikelets. Shading significantly exaggerated the inherently different ABA dynamics between the superior and inferior spikelets. We concluded that ABA levels are correlated with the dry matter accumulation patterns of spikelets. These results support our hypothesis that ABA is involved in assimilate partitioning among spikelets in a panicle during the initial phase of grain-filling of rice.  相似文献   

18.
This study compared the concentration of angiotensin-converting enzyme (ACE) inhibitory peptides at different stages of the bread-making process, including kneading, proofing, and final products. Steamed bread, baked bread, and soda crackers were produced with 3–20% addition of rye malt sourdoughs to assess products differing in their thermal treatment. Eight tripeptides with known or predicted ACE-inhibitory activity were quantified by LC/MS in multiple reaction monitoring (MRM) mode. In wheat sourdough and rye-malt gluten sourdough, IPP was the predominant tripeptide at 58 and 473 μmol kg−1, respectively, followed by LQP, IQP, and LPP. During the bread-making process, peptide concentrations were modified by enzymatic conversions at the dough stage and by thermal reactions during baking. The concentrations of IPP, LPP and VPP remained stable during dough preparation but decreased during thermal treatment; the concentrations of other peptides were changed at the dough stage but remained relatively stable during baking. The cumulative concentration of 8 ACE-inhibitory peptides in steamed bread and bread crumb exceeded 60 μmol kg−1, while soda crackers contained less than 3 μmol kg−1. The peptide levels in bread thus likely meet in vivo active concentrations.  相似文献   

19.
Pheromone-baited traps are an important sampling tool in integrated pest management programmes. Studies were conducted to determine the relationship between catches of male insects in these traps, and crop infestation. Numbers of male moths of the pink bollworm, Pectinophora gossypiella (Saunders) (Lepidoptera: Gelechiidae), caught daily in cotton fields at the University of Arizona Cotton Research Center, Phoenix, Arizona, in gossyplure-baited traps were variable. However, average catches of male moths for 3–7 days between boll-sampling periods were strongly correlated with oviposition on cotton bolls, percentages of infested bolls and numbers of larvae per boll. Average weekly numbers of moths emerging from infested cotton were also strongly correlated with the number of males caught: the number of females emerging was strongly correlated with oviposition on cotton bolls. Insecticide applications of carbaryl and fenvalerate reduced catches of male moths of pink bollworm in gossyplure-baited traps compared with catches in traps in untreated fields (average 56%). However, 13–48 male moths/trap per night were caught in the treated fields after applications. Thus, scheduling treatments on the basis of male moth trap catches, except for the initial treatment, was not feasible. Small field sizes, moth immigration and/or continuing emergence from the infested cotton in the fields may have obscured the impact of the insecticide treatments on adult moth populations.  相似文献   

20.
Background: Diabetes is a major public health problem. The development of new therapies that are able to improve glycemia management and even to cure diabetes is of great interest. In this study, protective effects of sodium tungstate against STZ-induced beta-cell damages were investigated. Methods: Sixty rats were divided into six groups: control, diabetic, sodium tungstate treated diabetic rats from one week before STZ injection (TDB), food-restricted diabetic (FRD), tungstate treated control, sodium tungstate treated diabetic rats from one week after STZ administration (TDA). We evaluated serum insulin, glucose and glucose tolerance; liver glycogen content, glucokinase (GK) activity; blood and pancreas antioxidant power, lipid peroxidation; and fuchsin-aldehyde histochemical staining of beta-cells. Results: Blood glucose levels of TDB group were lower than other diabetic groups (P<0.01). Blood insulin levels of all diabetic groups were lower than controls (P<0.01). Glucose intolerance improved in TDB animals. Blood and pancreas antioxidant power, liver glycogen contents and GK activities and granulated beta cells increased in TDB rats in comparison with other diabetic groups (P<0.01). Likewise, lipid peroxidation decreased significantly in TDB rats (P<0.01). Conclusions: Results suggested that sodium tungstate if administrated before STZ injection improves glycemic state by a direct effect on pancreatic beta-cells and preserves them by reducing the activity of these cells at the time of STZ injection, reducing STZ-induced oxidative stress, reducing insulin secretion, or all of the above mentioned.  相似文献   

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