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331.
332.

Phytohormones, including salicylic acid (SA) and jasmonic acid (JA) have the potential to ameliorate plant development and tolerance to deleterious effects of toxic metals like nickel (Ni). Therefore, the current study was carried out to evaluate SA and JA's interactive effect on the root antioxidative response of two Alyssum inflatum Nyár. populations against Ni-toxicity. Two A. inflatum species under different Ni concentrations (0, 100, 200, and 400 μM) were exposed to alone or combined levels of SA (0, 50, and 200 μM) and JA (0, 5, and 10 μM) treatments. Results showed that high Ni concentration (400 μM) reduced roots fresh weight in both populations than in control. However, external application of individual SA and JA or combined SA?+?JA in higher doses had ameliorated roots biomass by mitigating Ni-toxicity, especially in the NM population, in comparison to 400 μM Ni. Under Ni toxicity, SA and JA, especially their combination, induced high Ni accumulation in plants' roots. Moreover, the application of SA and JA alone, as well as combined SA?+?JA, was found to be effective in the scavenging of hydrogen peroxide by improving the activity of superoxide dismutase, peroxidase, catalase, and ascorbate peroxidase in both populations under Ni-toxicity. Overall, our results manifest that SA and JA's external use, especially combined SA?+?JA treatments, ameliorate root biomass and plant tolerance by restricting Ni translocation to the shoot, accumulating in roots, and enhancing antioxidant defense systems.

  相似文献   
333.
Self-organized industrial symbiosis (IS) starts with one actor's decision to invest in a waste recovery plant and the other actors' decision to buy the recovered flow. Technical and institutional conditions of the cluster influence actors' decisions. This paper explores the emergence of IS collaborations in industrial clusters under different techno-economic conditions in the long term. We propose a mixed-integer linear programming model that incorporates costs and constraints associated with waste recovery and exchange to study actors' investment decisions and investigate shaped symbiotic exchanges under rising energy prices and limited electricity supply. The approach is implemented in Iran's Persian Gulf Mining and Metals Special Economic Zone as a case study. The results revealed that changes in internal or external condition simultaneously influence the industrial and waste recovery plants. For instance, increasing energy prices without raising product prices significantly decreased the production level of industrial plants and, consequently, heat recovery potential. Furthermore, the waste heat recovery plants' contribution to improving the cluster's economic and environmental performance was not the same. Electricity recovery from a power plant's waste heat can result in 55 PJ grid electricity intake reduction and 720 M€ cluster cash flow increase. Recovered cooling or electricity from the steelmaking plant waste heat was consumed internally rather than shaping IS. These model outcomes show its capability to study IS within the socio-technical structure of the cluster, not a standalone phenomenon. Implemented conceptualization offers a novel system-level approach, which could be adjusted to assess other industrial development strategies.  相似文献   
334.
Bivalent copper complexes, [Cu(SB1)2] 1 (SB1=(2-(4-methylbenzylimino)methyl)-5-methylphenol, [Cu(SB2)2] 2 (SB2=(2-(4-methylbenzylimino)methyl)-4-bromolphenol), and [Cu(SB3)2] 3 (SB3=(2-(4-methylbenzylimino)methyl)-4,6-dibromophenol) were synthesized using the Schiff bases prepared from 4-methylbenzylamine (p-tolylmethanamine). These were characterized using a variety of spectro-analytical methods. For all copper complexes, a square planar geometry was determined through spectral analyses. Utilizing molecular orbital energies, the stability of the copper complexes was calculated from quantum chemical characteristics. The kinetic and thermal degradation parameters were calculated from the thermograms. Studies on DNA binding interactions, such as UV absorption and emission, have shown that the manner of DNA binding is intercalative, and the binding constant (Kb) order is 3 > 2 > 1 . Under oxidative and photolytic techniques, the copper complexes outperform the parent Schiff bases in their ability to cleave double-stranded pBR322 DNA. When tested for cytotoxicity on the KB3 and MCF7 cell lines, complexes displayed greater activity than their parent ligands. Studies on the complexes′ in-vitro antibacterial and antioxidant activity showed that they are significantly more powerful than the parent ligands.  相似文献   
335.
Cardiovascular diseases (CVDs) constitute one of the significant causes of death worldwide. Different pathological states are linked to CVDs, which despite interventions and treatments, still have poor prognoses. The genetic component, as a beneficial tool in the risk stratification of CVD development, plays a role in the pathogenesis of this group of diseases. The emergence of genome-wide association studies (GWAS) have led to the identification of non-coding parts associated with cardiovascular traits and disorders. Variants located in functional non-coding regions, including promoters/enhancers, introns, miRNAs and 5′/3′ UTRs, account for 90% of all identified single-nucleotide polymorphisms associated with CVDs. Here, for the first time, we conducted a comprehensive review on the reported non-coding variants for different CVDs, including hypercholesterolemia, cardiomyopathies, congenital heart diseases, thoracic aortic aneurysms/dissections and coronary artery diseases. Additionally, we present the most commonly reported genes involved in each CVD. In total, 1469 non-coding variants constitute most reports on familial hypercholesterolemia, hypertrophic cardiomyopathy and dilated cardiomyopathy. The application and identification of non-coding variants are beneficial for the genetic diagnosis and better therapeutic management of CVDs.  相似文献   
336.
Relative ethanol preference is a well-recognized phenotype in a number of species, including mice, but the molecular basis for this phenotype remains speculative. We generated novel recombinant inbred (RI) mouse lines from C57BL/6J (ethanol preferring) and BALB/c (ethanol avoiding) strains and evaluated the effect of ethanol feeding on the mRNA levels of three genes (Adh-1, Adh-2, andCas-1) of alcohol metabolism. Ethanol feeding affects the mRNA levels of all three genes in both a gene- and a genotype-specific manner. The effect of ethanol feeding onAhd-2 mRNA, in particular, is highly correlated with the relative ethanol acceptance of the genotypes. DNA sequencing of ∼500 bp of the 5′ upstream region of theAhd-2 gene has yielded identical sequence for the two strains and the genetically determined associated factors are hypothesized to be regulatory proteins. Quantitative trait locus analysis on the RI lines should lead to the molecular characterization and mapping of such gene-specific regulatory factors.  相似文献   
337.
Some of lizard species have the ability to lose their tail in order to defend against predators and regenerate the new tail. Lizard’s regenerated tail has attracted scientists’ attention for unraveling the regeneration process, but less information is known about the cellular characterization and cell growth properties of original tail. This research aimed to report cell culture and banking process of rough-tailed gecko or Cyrtopodion scabrum’s original tail cell sample from inner tissue without skin using tissue explant technique. For banking reports, it is essential to analyze this cells’ potential to proliferate, to investigate biological aspects such as cell culture features, differentiation and chromosome number and to report its species identification and quality control. To achieve optimal growth conditions, three different temperatures for incubation including 18, 23 and 37 °C and two different media including DMEM and L-15 were applied. The expanded cells were studied for their potential to adipose and osteoblast differentiation. Results indicated that lizard’s original tail cells could be successfully obtained by explant technique. The cells demonstrated fibroblast like morphology with population doubling times of approximately 24?±?0.5 h. Karyotyping analysis showed a distribution of 2n?=?40 chromosome number for this cell line. The comparison of different incubation media and temperatures showed that cell growth is equally optimal in all mentioned conditions according to growth curves. Adipose and osteoblast differentiation was obviously observed in these cells which confirms the hint of stem-ness in the produced mixed cells. According to cell banking policies, produced cells were also checked for bacterial, fungal, yeast and mycoplasma contaminations and no contamination was observed. Multiplex PCR for identification of species confirmed the species of lizard with no cross-contamination with other cells in the cell bank. Establishment of authenticated and well-characterized lizard’s original tail cell line will provide a valuable source for subsequent in vitro regenerative research and molecular studies which are not feasible in in vivo methods. This finding will allow us to get an opportunity to create and preserve a new collection of lizard cell lines in the future.  相似文献   
338.
The citrus leafminer (CLM), Phyllocnistis citrella Stainton, is one of the most serious pests of Iran's citrus nursery stocks. In this study, the effects of gamma radiation at doses of 100–450?Gy on the biological and reproductive parameters of P. citrella were determined. The results showed that the mean percentage of pupal mortality increases with a rise in the dose. Also, the mean values of this parameter were higher for irradiated females, indicating higher sensitivity. The mean fertility of the irradiated females mated with normal males was affected drastically and reached zero at 300?Gy. The hatchability of the eggs laid by normal females mated with irradiated males dropped to 2% at the highest irradiation dose of 450?Gy. The results of this test showed that females have a higher radio-sensitivity than males. The competitiveness values fluctuated from 0.2 to 0.6 at doses higher than 200?Gy. The results showed that the male CLMs irradiated with sterilizing doses could compete suitably with the untreated males in laboratory conditions.  相似文献   
339.
Fractionation of methanolic extracts of air dried aerial parts ofParthenium resulted in the isolation of a toxic constituent which was identified as parthenin, the major sesquiterpene lactone from the weed. The LD50 (minimal lethal dose required to cause 50% mortality) for parthenin in rats was 42 mg/kg body weight. When [3H]-parthenin was given orally or by intravenous administration, radioactivity appeared in the milk of lactating laboratory and dairy animals. Tissue distribution of radioactivity revealed that maximum label was detectable in kidneys.  相似文献   
340.
In order to achieve accurate chromosome segregation, eukaryotic cells undergo a dramatic change in morphology to obtain a spherical shape during mitosis. Interphase cells communicate directly with each other by exchanging ions and small molecules via gap junctions, which have important roles in controlling cell growth and differentiation. As cells round up during mitosis, the gap junctional communication between mitotic cells and adjacent interphase cells ceases. Whether mitotic cells use alternative mechanisms for mediating direct cell-cell communication during rounding is currently unknown. Here, we have studied the mechanisms involved in the remodeling of gap junctions during mitosis. We further demonstrate that mitotic cells are able to form actin-based plasma membrane bridges with adjacent cells during rounding. These structures, termed “mitotic nanotubes,” were found to be involved in mediating the transport of cytoplasm, including Rab11-positive vesicles, between mitotic cells and adjacent cells. Moreover, a subpool of the gap-junction channel protein connexin43 localized in these intercellular bridges during mitosis. Collectively, the data provide new insights into the mechanisms involved in the remodeling of gap junctions during mitosis and identify actin-based plasma membrane bridges as a novel means of communication between mitotic cells and adjacent cells during rounding.  相似文献   
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