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1.
The extensive use of nanoparticles (NPs) in diverse applications causes their localization to aquatic habitats, affecting the metabolic products of primary producers in aquatic ecosystems, such as algae. Synthesized calcium oxide nanoparticles (CaO NPs) are of the scarcely studied NPs. Thus, the current work proposed that the exposure to CaO NPs may instigate metabolic pathway to be higher than that of normally growing algae, and positively stimulate algal biomass. In this respect, this research was undertaken to study the exposure effect of CaO NPs (0, 20, 40, 60, 80, and 100 µg mL−1 ) on the growth, photosynthesis, respiration, oxidative stress, antioxidants, and lipid production of the microalga Coccomyxa chodatii SAG 216-2. The results showed that the algal growth concomitant with chlorophyll content, photosynthesis, and calcium content increased in response to CaO NPs. The contents of biomolecules such as proteins, amino acids, and carbohydrates were also promoted by CaO NPs with variant degrees. Furthermore, lipid production was enhanced by the applied nanoparticles. CaO NPs induced the accumulation of hydrogen peroxide, while lipid peroxidation was reduced, revealing no oxidative behavior of the applied nanoparticles on alga. Also, CaO NPs have a triggering effect on the antioxidant enzymes such as superoxide dismutase, catalase, ascorbate peroxidase, and guaiacol peroxidase. The results recommended the importance of the level of 60 µg mL−1 CaO NPs on lipid production (with increasing percentage of 65% compared to control) and the highest dry matter acquisition of C. chodatii. This study recommended the feasibility of an integrated treatment strategy of CaO NPs in augmenting biomass, metabolic up-regulations, and lipid accumulation in C. chodatii.  相似文献   
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Results of the effect of Phosphamidon on soil, root- and leaf-surface fungi of Vigna sinensis var. azmerly were generally inconsistent. However, there were some consistent ones. Its effect on soil, root- and leaf-surface fungi persisted till after 40 days. In soil the total count was regularly increased after 20 days by the low and medium doses and after 40 days by the high dose. In the rhizosphere, Fusarium was almost consistently activated by the three doses after 5 days of treatment and by the low dose after 20 days. In the rhizoplane, the total count of fungi was lowered by the three doses after 40 days in the two sowings. Alternaria alternata was toxicated by the three doses after several experimental periods of the two sowings in the phyllosphere and phylloplane. When this insecticide was incorporated with the agar medium, it was of no significant effect on the total count of fungi at the low and medium doses but abnormally increased the total count at the high dose. In the liquid medium, the mycelia of the test fungi were not significantly affected except that of Penicillium corylophilum which was significantly retarded by the three doses and Rhizopus stolonifer which was significantly activated by the high dose.  相似文献   
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Neurochemical Research - Acrylamide (ACR) is an environmental pollutant with well-demonstrated neurotoxic and neurodegenerative effects in both humans and experimental animals. The present study...  相似文献   
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The synthesis and SAR studies of spiroquinazolinones as novel PDE7 inhibitors are discussed. The best compounds from the series displayed nanomolar inhibitory affinity and were selective versus other PDE isoenzymes.  相似文献   
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Melatonin was orally given to rats at the dosage of 0.75 mg/rat/day for 7 days and challenged on the day 7 with a single toxic dose of indomethacin (20 mg/kg, intramuscularly) to test either protection afforded by melatonin against indomethacin-induced oxidative tissue damage or effects of repeated administration of this hormone on some testicular metabolic parameters. The results showed increased lipid peroxidation, as evidenced by the formation of thiobarbituric acid reactive substances, accompanied by non-significantly decreased glutathione content in the testis of rats treated with indomethacin. However, prior administration of melatonin failed to prevent indomethacin-induced testicular lipid peroxidation. No change in the production of lipid peroxidation and glutathione was observed as well after treatment with melatonin alone. Meanwhile, exogenous melatonin inhibited testicular levels of total lipid, total protein, and activity of aspartate aminotransferase, alanine aminotransferase, and alkaline phosphatase. All treated rats exhibited unchanged activity of both acid phosphatase and lactate dehydrogenase. The results indicated inability of oral administration of melatonin to prevent some of the oxidative damaging effects of indomethacin in the rat testis. In addition, the study provided an evidence that melatonin has an inhibitory action on the testicular metabolism in adult rats and thereby suggests a possible role of this hormone in modulating functions of rat testis.  相似文献   
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There is a great deal of interest in neurotrophin therapy to prevent neuronal degeneration. The present study aimed at synthesizing new functionalized indole derivatives with structures justifying neuroprotective activity using L-tryptophan (TRP) as starting material. The potential neuroprotective effect of these newly synthesized agents against acrylamide (ACR) induced neurotoxicity was investigated in adult female rats. The novel indole derivatives, indolylmethyl pyridine derivatives 9a,b, pyrimidinylindolyl propanone derivatives 12a-c, pyrazolylindolyl propanone derivatives 14a,b, and indolyl tetrazolopropanoic acid derivative 17 were synthesized and their chemical structures were confirmed by studying their analytical and spectral data. The administration of ACR [ip, 50mgkg(-1) body weight (b. wt.)] alone resulted in significant increase in brain malondialdehyde level (MDA) and lactate dehydrogenase (LDH) activity whereas it caused significant decrease in brain monoamines levels and antioxidant enzymes activity. Treatment with the indole derivatives 9b, 12c, 14a, and 17 (ip, 50mgkg(-1) b. wt.) prior to ACR produced neuroprotective activity with various intensities depending on the structure of each compound. Compound 17 in which the tetrazole ring was attached to the TRP moiety ranked as the strongest neuroprotective agent. All the tested compounds have been shown to possess antioxidant properties offering promising efficacy against oxidative stress induced by ACR administration.  相似文献   
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The challenge in working with anthraquinone-2'-deoxyadenosine (AQ-dA) conjugates is that they are insoluble in water and only sparingly soluble in most organic solvents. However, water-soluble AQ-dA conjugates with short linkers are required for study of their electrochemical and intramolecular electron transfer properties in this solvent prior to their use in laser kinetics investigations of photoinduced hole (cation) transport in DNA. This article first describes the synthesis of a water-soluble, ethynyl-linked AQ-dA conjugate, 8-[(anthraquinone-2-yl)ethynyl]-2'-deoxyadenosine 3'-benzyl hydrogen phosphate, based on initial formation of a 5'-O-(4,4'-dimethoxytrityl) (5'-O-DMTr) intermediate. Because intended H2 over Pd/C reduction of the ethynyl linker in 5'-O-DMTr-protected 2'-deoxyadenosines cleaves the DMTr protecting group and precipitates multiple side products, this work also describes the synthesis of an ethylenyl-linked AQ-dA conjugate, 8-[2-(anthraquinone-2-yl)ethyl]-2'-deoxyadenosine 3'-benzyl hydrogen phosphate, starting with a 5'-O-tert-butyldiphenylsilyl protecting group.  相似文献   
10.
Increasing evidences suggest that mitochondrial dysfunction plays an important role in the pathogenesis of neurodegenerative diseases including Alzheimer's disease (AD). Alterations of mitochondrial efficiency and function are mainly related to alterations in mitochondrial content, amount of respiratory enzymes, or changes in enzyme activities leading to oxidative stress, mitochondrial permeability transition pore opening, and enhanced apoptosis. More recently, structural changes of the network are related to bioenergetic function, and its consequences are a matter of intensive research. Several mitochondria-targeting compounds with potential efficacy in AD including dimebon, methylene blue, piracetam, simvastatin, Ginkgo biloba, curcumin, and omega-3 polyunsaturated fatty acids have been identified. The majority of preclinical data indicate beneficial effects, whereas most controlled clinical trials did not meet the expectations. Since mitochondrial dysfunction represents an early event in disease progression, one reason for the disappointing clinical results could be that pharmacological interventions might came too late. Thus, more studies are needed that focus on therapeutic strategies starting before severe disease progress.  相似文献   
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