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1.
Molecular Biology Reports - A cluster of many risk factors for type 2 diabetes and cardiovascular disease is used to describe the metabolic syndrome (MetS). Moreover, genetic differences associated...  相似文献   
2.
Our aim was to evaluate the protective and antioxidant effects of ginger extract against cadmium-induced renal toxicity in animal models and to support the use of ginger as anti-renal failure natural remedy. Seventy rats were examined in a 4-week experiment to evaluate the effect of Ginger (Zingiber officinale) at doses of 100 and 200 mg/kg body weight on molecular DNA content, antioxidant status, and renal function in rats intoxicated with cadmium at dose of (5 mg/kg) using biochemical and histological analysis. Renal dysfunction, kidney tissue damage, and oxidative effect were evident in cadmium intoxicated rats as estimated by significant increase in (creatinine, urea), decrease in (creatinine clearance and reabsorption rate of urine albumin), increase in MDA, decrease in total antioxidant status (TAC), reduction in DNA content, and histopathological changes of kidneys’ tissues compared to control rats. Treatment with ginger resulted in significant restoring of renal function biomarkers, TAC, molecular DNA, and histological improvements which occurs via free radical scavenging and regenerative mechanisms. The activity of ginger was supported by estimation of bioactive phenolic and falvinods constituents. Twenty-eight polyphenolic compounds were estimated in ginger extract; [6]-gingerol, [6]-shogaol, citral and pyrogallol were the highest amounts in ginger, and supposed to be responsible for its major antioxidant and free radical scavenging activity as shown by In vitro DPPH/β-carotene-linolic acid assay tests. Consequently, ginger extracts could have a potent protective effects against nephrotoxicity induced by various toxicants.  相似文献   
3.
We posed the question of whether steady-state levels of the higher polyamines spermidine and spermine in plants can be influenced by overexpression of a heterologous cDNA involved in the later steps of the pathway, in the absence of any further manipulation of the two synthases that are also involved in their biosynthesis. Transgenic rice (Oryza sativa) plants engineered with the heterologous Datura stramonium S-adenosylmethionine decarboxylase (samdc) cDNA exhibited accumulation of the transgene steady-state mRNA. Transgene expression did not affect expression of the orthologous samdc gene. Significant increases in SAMDC activity translated to a direct increase in the level of spermidine, but not spermine, in leaves. Seeds recovered from a number of plants exhibited significant increases in spermidine and spermine levels. We demonstrate that overexpression of the D. stramonium samdc cDNA in transgenic rice is sufficient for accumulation of spermidine in leaves and spermidine and spermine in seeds. These findings suggest that increases in enzyme activity in one of the two components of the later parts of the pathway leading to the higher polyamines is sufficient to alter their levels mostly in seeds and, to some extent, in vegetative tissue such as leaves. Implications of our results on the design of rational approaches for the modulation of the polyamine pathway in plants are discussed in the general framework of metabolic pathway engineering.  相似文献   
4.
The availability of variable genetic markers for groupers (Serranidae) has generally been limited to mitochondrial DNA. For studies of population genetic structure, more loci are usually required; particularly useful are those that are nuclear in origin such as microsatellites. Here, we isolated and characterized 9 microsatellite loci from the endemic Hawaiian grouper Epinephelus quernus using a biotin-labeled oligonucleotide-streptavidin–coated magnetic bead approach. Of the 20 repeat-containing fragments isolated, 15 had sufficient flanking region in which to design primers. Among these, 9 produced consistent polymerase chain reaction product, and 6 were highly variable. These 6 loci were all composed of dinucleotide repeats, with the number of alleles ranging from 6 to 18, and heterozygosities from 33.3% to 91.7%. The high levels of variability observed should make these markers useful for population genetic studies of E. quernus, and potentially other epinephelines.  相似文献   
5.
With the amount of available sequence data rapidly increasing, supermatrices are at the forefront of systematic studies. As an alternative to supertrees, supermatrices utilize a total evidence approach where different genes and other lines of data are merged into a single data matrix, which is then analyzed in an attempt to obtain the phylogeny that best explains the data. However, questions may arise when combining data sets in which one or more taxa do not have sequences available for each individual gene. Two possible solutions to this situation are to either leave all taxa separate and code unavailable sequences as missing, or to combine taxa at a level for which monophyly is assumed a priori. By reanalyzing the previous work of, we show that combining taxa may yield misleading results, i.e., hypotheses of relationships that are not supported by the underlying data.  相似文献   
6.
The effects of ionizing radiation on biological cells have been reported in several literatures. Most of them were mainly concerned with doses greater than 0.01 Gy and were also concerned with gamma rays. On the other hand, the studies on very low dose fast neutrons (VLDFN) are rare. In this study, we have investigated the effects of VLDFN on cell membrane and protein secondary structure of rat erythrocytes. Twelve female Wistar rats were irradiated with neutrons of total dose 0.009 Gy (241Am-Be, 0.2 mGy/h) and twelve others were used as control. Blood samples were taken at the 0, 4th, 8th, and 12th days postirradiation. Fourier transform infrared (FTIR) spectra of rat erythrocytes were recorded. Second derivative and curve fitting were used to analysis FTIR spectra. Hierarchical cluster analysis (HCA) was used to classify group spectra. The second derivative and curve fitting of FTIR spectra revealed that the most significant alterations in the cell membrane and protein secondary structure upon neutron irradiation were detected after 4 days postirradiation. The increase in membrane polarity, phospholipids chain length, packing, and unsaturation were noticed from the corresponding measured FTIR area ratios. This may be due to the membrane lipid peroxidation. The observed band shift in the CH2 stretching bands toward the lower frequencies may be associated with the decrease in membrane fluidity. The curve fitting of the amide I revealed an increase in the percentage area of α-helix opposing a decrease in the β-structure protein secondary structure, which may be attributed to protein denaturation. The results provide detailed insights into the VLDFN effects on erythrocytes. VLDFN can cause an oxidative stress to the irradiated erythrocytes, which appears clearly after 4 days postirradiation.  相似文献   
7.
Individual mouse strains differ significantly in terms of behavior and cognitive function. Strain-specific variation of metabolic protein levels in the hippocampus among various commonly used mouse strains, however, has not been investigated yet. A proteomic approach based on two-dimensional gel electrophoresis (2-DE) coupled with mass spectrometry [high capacity ion trap (HCT)] has been chosen to address this question by determining strain-dependent levels of metabolic proteins in hippocampal tissue of four inbred and one outbred mouse strain. Statistical analysis of protein spots on 2-DE gels of the individual strains (n = 10) revealed significant strain-dependent differences in densities of 39 spots. Subsequent HCT analysis led to the identification of 22 different metabolic proteins presenting with differential protein levels among the five mouse strains investigated. Among those are proteins concerned with the metabolism of amino acid, nucleic acid, carbohydrate and energy. Moreover, proteins known to play a pivotal role in the processes of learning and memory, such as calcium/calmodulin-dependent protein kinase type II alpha chain, were found to present with significant inter-strain variability, which is also in agreement with our previous reports. Strain-specific protein levels of metabolic proteins in the mouse hippocampus may provide some insight into the molecular underpinnings and genetic determination of strain-dependent neuronal function. Furthermore, data presented herein emphasize the significance of the genetic background for the analysis of metabolic pathways in the hippocampus in wild-type mice as well as in gene-targeting experiments.  相似文献   
8.
A series of new 9-glycosyl-4,9-dihydropyrano[3,4-b]indole-1(3H)-ones 3 was synthesized in moderate to low yields. 4,9-Dihydropyrano[3,4-b]indole-1(3H)-ones (1) were coupled with different acetobromoglycopyranoses 2 in refluxing toluene in the presence of silver oxide to afford one coupling product of the respective N-glycosides. α-L-Arabinopyranosides 3j and 3m were the most active glycosides among the tested compounds against certain Gram positive and Gram negative bacterial strains.  相似文献   
9.

Background

In spite of our extensive knowledge of the more than 20 proteins associated with different amyloid diseases, we do not know how amyloid toxicity occurs or how to block its action. Recent contradictory reports suggest that the fibrils and/or the oligomer precursors cause toxicity. An estimate of their temporal concentration may broaden understanding of the amyloid aggregation process.

Methodology/Principal Findings

Assuming that conversion of folded protein to fibril is initiated by a nucleation event, we back-calculate the distribution of nuclei concentration. The temporal in vitro concentration of nuclei for the model hormone, recombinant human insulin, is estimated to be in the picomolar range. This is a conservative estimate since the back-calculation method is likely to overestimate the nuclei concentration because it does not take into consideration fibril fragmentation, which would lower the amount of nuclei

Conclusions

Because of their propensity to form aggregates (non-ordered) and fibrils (ordered), this very low concentration could explain the difficulty in isolating and blocking oligomers or nuclei toxicity and the long onset time for amyloid diseases.  相似文献   
10.
Abstract Prays oleae Bern, (OM) and Palpita unionalis Hüb., (JM) are two of the most important pests in olive groves in Egypt. A 3‐year monitoring study using sex pheromone traps in semi‐arid and arid olive groves was performed. In the semi‐arid grove, flight pattern of the OM was the same as in other Mediterranean countries, but in dates concordating plant phenology. The moth completes three generations annually: the first flight is in March to April, the second is in May to June and the third occurs in August to October. In the arid olive grove, an interesting flight pattern was observed. First flight was always very close or overlapped with the second one with no male catches during August to October. However, eggs were present most of the season, indicating unusually high female presence and oviposition activity of the OM during the absence of males in the traps. Generally, moth densities were significantly lower in low fruiting years than in higher ones and were also lower in the arid olive grove than in the semi‐arid one. In contrast, JM males were present all season, exhibiting six to seven and three to four overlapping flight peaks in arid and semi‐arid olive groves, respectively. Moth densities were significantly higher in the arid olive grove than those in the semi‐arid one. This study shows that trapping location and fruit bearing year are characteristics that strongly affect the grove‐specific information needed to estimate correctly adult emergence and thus the timing of control measures.  相似文献   
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