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Interaction of plant roots with arbuscular mycorrhizal fungi (AMF) is a complex trait resulting in cooperative interactions among the two symbionts including bidirectional exchange of resources. To study arbuscular mycorrhizal symbiosis (AMS) trait variation in the model plant Lotus japonicus, we performed an integrated multi‐omics analysis with a focus on plant and fungal phospholipid (PL) metabolism and biological significance of lysophosphatidylcholine (LPC). Our results support the role of LPC as a bioactive compound eliciting cellular and molecular response mechanisms in Lotus. Evidence is provided for large interspecific chemical diversity of LPC species among mycorrhizae with related AMF species. Lipid, gene expression and elemental profiling emphasize the Lotus–Glomus intraradices interaction as distinct from other arbuscular mycorrhizal (AM) interactions. In G. intraradices, genes involved in fatty acid (FA) elongation and biosynthesis of unsaturated FAs were enhanced, while in Lotus, FA synthesis genes were up‐regulated during AMS. Furthermore, FAS protein localization to mitochondria suggests FA biosynthesis and elongation may also occur in AMF. Our results suggest the existence of interspecific partitioning of PL resources for generation of LPC and novel candidate bioactive PLs in the Lotus–G. intraradices symbiosis. Moreover, the data advocate research with phylogenetically diverse Glomeromycota species for a broader understanding of the molecular underpinnings of AMS.  相似文献   
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Both kidneys of mature pigs received a single dose of 9.8 Gy 60Co gamma rays. Pigs were killed between 2 and 24 weeks after irradiation and the kidneys examined histologically. Glomerular and tubular changes were observed within 2 weeks of irradiation. Neutrophils and other leukocytes were seen within glomerular capillary loops; mesangial matrix and cell number increased. A progressive increase in thickening of the basement membrane and a decrease in capillary lumina were then noted. Basement membrane duplication occurred within 12 weeks. By 24 weeks these lesions had increased in severity, sclerotic endstage glomeruli, predominantly subcapsular or juxtamedullary, being evident. Tubular lesions initially consisted of focal areas of tubular atrophy in the juxtamedullary region. By 6 weeks subcapsular foci of tubular degeneration, regeneration, and necrosis were found; these appeared to resolve 12 weeks after irradiation. At later times the severity of the tubular lesions varied between pigs, with some exhibiting interstitial fibrosis involving a complete band of subcapsular tissue, while others showed relatively mild changes. There was no apparent change in the vasculature. These findings indicate that (a) there is no one target or dose-limiting cell, and (b) the vasculature does not play a primary role in the development of radiation nephropathy.  相似文献   
125.
Nonexchangeable soil K trapped between interlayers of clay minerals is an important source of K for plants grown on many soils. In this study, the ability of alfalfa, as the most important forage crop worldwide, to take up K from some micaceous minerals and to promote the transformation of micaceous minerals were investigated. Alfalfa was cultivated in pots that consisted of a mixture of Hamadan quartz sand and Amlash biotite, Hamadan muscovite and Hamadan phlogopite. Plants were irrigated with distilled water and complete or K-free nutrient solutions. After 90 days, K uptake by plants was measured by flame photometer. Also, the clay size particles in each pot were analyzed using x-ray diffraction. It was found that alfalfa was able to induce a significant release of interlayer K during cropping. The amount of K taken up by alfalfa was significantly higher for Hamadan phlogopite. X-ray diffractometry showed a strong vermiculitization of Hamadan phlogopite and Amlash biotite, but no X-ray detectable transformation of muscovite was recognized.  相似文献   
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The citrus cottony scale, Pulvinaria aurantii Cock. (Hem.: Coccidae) is one of the most important citrus pests in Iran. This study investigated the toxicity and synergistic effects of organophosphorous insecticides (Malathion, Chlorpyrifos, Buprofezin and DG oil) on first nymphal instars of P. aurantii in the laboratory conditions (25?±?1?°C, 75?±?5% RH and 16L:8D photoperiod). The values of LC50 for Malathion, Chlorpyrifos and Buprofezin insecticides on the first nymphal instars were calculated as 76.90, 105.25 and 24.70?ppm, respectively. Also, results indicated that Buprofezin and Pyriproxifen are the most effective insecticides on first nymphal instars of P. aurantii. The values of LC50 for each insecticide without oil and in half dose along with DG oil were equal. This was an indication for synergism role of DG oil combination. The results of this study showed that DG oil not only decreases the consumption of insecticides, but also increases their efficacy.  相似文献   
128.
Cancer therapy using oncolytic viruses is an emerging area, in which viruses are engineered to selectively propagate in tumor tissues without affecting healthy cells. Because of the advantages that adenoviruses (Ads) have over other viruses, they are more considered. To achieve tumor selectivity, two main modifications on Ads genome have been applied: small deletions and insertion of tissue- or tumor-specific promoters. Despite oncolytic adenoviruses ability in tumor cell lysis and immune responses stimulation, to further increase their antitumor effects, genomic modifications have been carried out including insertion of checkpoint inhibitors and antigenic or immunostimulatory molecules into the adenovirus genome and combination with dendritic cells and chemotherapeutic agents. This study reviews oncolytic adenoviruses structures, their antitumor efficacy in combination with other therapeutic strategies, and finally challenges around this treatment approach.  相似文献   
129.
A Rezvani  J P Huidobro-Toro  E L Way 《Life sciences》1982,31(20-21):2367-2370
The rate and degree of in vitro tolerance development to morphine, normorphine and d,1-methadone were assessed on the excised guinea pig ileum. Agonists in fixed concentrations at 1/4, 1/2, 1 and 2 x IC50 were incubated with the tissue for 1, 2 or 4 hours. The degree of tolerance development was expressed as a ratio of the IC50 after and before incubation. A high degree of tolerance developed to all three agonists and the effect could be prevented by co-incubation with naloxone. Tolerance development was stereo-specific; levorphanol and 1-methadone developed much higher degrees of tolerance than their respective d-isomers. Furthermore, under the same conditions, subsensitivity to acetylcholine, norepinephrine, and adenosine monophosphate did not develop. The in vitro tolerance was accompanied by physical dependence development as evidenced by the fact that naloxone elicited muscular contracture in the tolerant ileum. cAMP enhanced the development of tolerance to normorphine and cycloheximide could reduce this phenomenon. It is concluded that the procedure may facilitate studies on the mechanisms involved in the development of opiate tolerance and physical dependence.  相似文献   
130.
We have systematically investigated six compendial nonionic detergents as potential replacements for Triton ×-100 in bioprocessing applications. Use of compendial raw materials in cGMP bioprocessing is advantageous for a variety of reasons including material specifications developed to meet stringent pharmaceutical product quality requirements, regulatory familiarity and comfort, and availability from vendors experienced supplying the biopharmaceutical industry. We first examine material properties of the detergents themselves including melting point and viscosity. Process performance and product contact in real-world bioprocess applications are then investigated. Lastly, we test the detergents in virus inactivation (VI) experiments with recombinant proteins and adeno-associated virus. Two of the detergents tested, PEG 9 Lauryl Ether and PEG 6 Caprylic/Capric Glycerides, showed favorable properties that make them attractive for use as potential Triton X-100 replacements. Process performance testing indicated negligible impact of the detergents on product yield, purity, and activity compared to a control with no detergent. Importantly, both PEG 9 Lauryl Ether and PEG 6 Caprylic/Capric Glycerides demonstrated very fast VI kinetics with complete inactivation of XMuLV observed in less than 1 min at a target 1% detergent concentration. Potential advantages and disadvantages of both candidate detergents for use in cGMP bioprocessing are summarized and discussed.  相似文献   
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