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251.
Ahammed Golam Jalal Li Yang Cheng Yuan Liu Airong Chen Shuangchen Li Xin 《Journal of Plant Growth Regulation》2020,39(4):1414-1424
Journal of Plant Growth Regulation - Germination is a crucial event in plant lifecycle mediated by a complex hormonal crosstalk. In this study, we revealed an antagonistic interaction between... 相似文献
252.
Capecitabine is a chemotherapeutic agent used for the treatment of patients with metastatic cancers. This study aimed at determining the drug capecitabine in a simple chemiluminescence (CL) system of acidic potassium permanganate using the stopped‐flow injection technique. Statistical methods were used to detect optimum conditions. The method showed two linear calibration ranges from 6.7 × 10?6 to 6.7 × 10?5 mol L?1 and from 6.7 × 10?5 to 2.7 × 10?3 mol L?1 with a detection limit of 1.5 × 10?6 mol L?1. Chitosan‐modified magnetic nanoparticles were studied in the drug‐delivery experiments. According to the pH sensitivity of chitosan and low pH values in tumour cells, the chitosan‐coated magnetic nanoparticles could provide a good targeting drug‐delivery system to tumour sites. To evaluate the applicability of the method, the capecitabine‐loaded magnetic chitosan nanoparticles were synthesized with two different cross‐linkers; loading and releasing rates of the drug were investigated using the proposed CL method and an ultraviolet–visible light spectrophotometric method (absorption at 305 nm). The results showed a good correlation between the two methods, and it was found that the synthesized chitosan‐modified magnetic nanoparticles could be used for pH‐dependent release of capecitabine in cancer cells. Moreover, determination of capecitabine in tablets and synthetic samples was performed. 相似文献
253.
254.
Abstract Hydrochus ignicollis Motschulsky, 1860 is recorded from Iran (Gilan Province) for the first time. In addition, new Iranian provincial records are provided for two species: H. nodulifer Reitter, 1897 (Zanjan Province) and H. farsicus Hidalgo-Galiana, Jäch, and Ribera, 2010 (Kohgiluyeh and Boyer-Ahmad Province). Photographs of the habitus, the male genitalia and the habitat of H. ignicollis are provided. 相似文献
255.
Nitric oxide (NO) is a free radical that is produced in cells from l-arginine. NO is involved in the physiological control of different tissues, but it can act as a toxic mediator in the cells. In this study we investigated the effect of l-arginine on the genotoxicity induced by methyl methanesulfonate (MMS) in human lymphocytes. Blood was treated with NG-nitro-l-arginine methyl ester (l-NAME) as an inhibitor of nitric oxide synthase for finding out the role of NO in this effect. Human whole blood was treated with l-arginine (50, 100 and 250 μM) and/or l-NAME, then it was treated in vitro with MMS after 24 h of culture. The lymphocytes were stimulated by phytohemagglutinin to find out the micronuclei in cytokinesis-blocked binucleated cells. DNA fragmentation of lymphocytes was detected by using a fluorescence microscope after propidium iodide staining. These data showed that arginine increased the frequency of MMS-induced micronuclei in lymphocytes. However, the genotoxicity was decreased by using l-NAME. Arginine and l-NAME have not shown any DNA damage in cultured human lymphocytes. In conclusion, addition of l-arginine to MMS as an alkylating agent caused an increase of DNA damage in human lymphocytes. This enhancement of genotoxicity was reduced by NAME as NO inhibitor. It is thus cleared that an increase of DNA damage by arginine and MMS is related to NO production. 相似文献
256.
Syed Hamid Jalal Shah Noreen Malik Amir Humayun Malik Muhebullah Faqiri 《Archives Of Phytopathology And Plant Protection》2013,46(5-6):497-500
B. tabaci exists as a complex of morphologically very similar but genetically different variants previously termed as biotypes and more recently as cryptic species. Using a region of mitochondrial cytochrome oxidase, I (mtCO-I) gene sequences this study for the first time identified at molecular level the presence of two cryptic species of B. tabaci; Asia-I and Asia-II-5 from cotton grown in the fields of Bland Ghar, Bihsud district, Nangarhar province of Afghanistan. It is the first report of its type as this insect was not reported earlier from any crop or area of this country at species level. 相似文献
257.
Moloud Gholamzadeh Chitgar Roya Khosravi Jalal JalaliSendi Mohammad Ghadamyari 《Archives Of Phytopathology And Plant Protection》2013,46(7):781-788
Sublethal effects of Thymus vulgaris were investigated on life-table parameters of Tetranychus urticae Koch (Acari: Tetranychidae) in the laboratory conditions at 25?±?1?°C, 70?±?10% RH and a 14:10?h (L:D) photoperiod. Bioassay was conducted to assess the effect of different concentrations of T. vulgaris essential oil on two-spotted spider mite. LC50 and LC20 of T. vulgaris on T. urticae were calculated as 18.86 and 6.24?μl/litre air for 24?h after treatment. In the sublethal effects, after 24?h exposure to LC50 concentration, mortality, fecundity and longevity of the females that survived from treatment were determined. Results showed that T. vulgaris caused significant reductions in fecundity and longevity of adults. Life-table assay indicated that the intrinsic rate of increase (r m), net reproductive rate (R 0), finite rate of increase (λ), mean generation time (T), significantly reduced in treated females compared to control. These results suggest that T. vulgaris could be incorporated in integrated pest management programmes of T. urticae. 相似文献
258.
Evelyn Assadian Mohammad Hadi Zarei Ali Ghanadzadeh Gilani Mehrzad Farshin Hamid Degampanah Jalal Pourahmad 《Biological trace element research》2018,184(2):350-357
CuO nanoparticles (CuO-NPs) serve several important functions in human life, particularly in the fields of medicine, engineering, and technology. These nanoparticles have been utilized as catalysts, semiconductors, sensors, gaseous and solid ceramic pigments, and magnet rotatable devices. Further use for CuO-NPs has been employed in the pharmaceutical industry especially in the production of anti-microbial fabric treatments or prevention of infections caused by Escherichia coli and methicillin-resistant Staphylococcus aureus. Two key potential routes of exposure to CuO-NPs exist through inhalation and skin exposure. Toxicity of these nanoparticles has been reported in various studies; however, no study as of yet has investigated the complete cellular mechanisms involved in CuO-NPs toxicity on human cells. The aim of this study was to determine the cytotoxicity of CuO-NPs on human blood lymphocytes. Blood lymphocytes were obtained from healthy male subjects through the use of Ficoll polysaccharide subsequently by gradient centrifugation. The following parameters were assayed in blood lymphocytes after a 6-h incubation with different concentrations of CuO-NPs: cell viability, reactive oxygen species (ROS) formation, lipid peroxidation, cellular glutathione levels, and mitochondrial and lysosomal damage. Our results demonstrate that CuO-NPs, in particular, decreased cell viability in a concentration-dependent manner and the IC50 determined was 382 μM. CuO-NP cytotoxicity was associated with significant increase at intracellular ROS level and loss of mitochondrial membrane potential and lysosomal membrane leakiness. Hence, CuO-NPs are shown to effectively induce oxidative stress in addition to inflict damage on mitochondria and lysosomes in human blood lymphocytes. 相似文献
259.
Rizwana Naureen Muhammad Tariq Ismail Yusoff Ahmed Jalal Khan Chowdhury Muhammad Aqeel Ashraf 《Saudi Journal of Biological Sciences》2015,22(3):332-339
Methyl esters from vegetable oils have attracted a great deal of interest as substitute for petrodiesel to reduce dependence on imported petroleum and provide an alternate and sustainable source for fuel with more benign environmental properties. In the present study biodiesel was prepared from sunflower seed oil by transesterification by alkali-catalyzed methanolysis. The fuel properties of sunflower oil biodiesel were determined and discussed in the light of ASTM D6751 standards for biodiesel. The sunflower oil biodiesel was chemically characterized with analytical techniques like FT-IR, and NMR (1H and 13C). The chemical composition of sunflower oil biodiesel was determined by GC–MS. Various fatty acid methyl esters (FAMEs) were identified by retention time data and verified by mass fragmentation patterns. The percentage conversion of triglycerides to the corresponding methyl esters determined by 1H NMR was 87.33% which was quite in good agreement with the practically observed yield of 85.1%. 相似文献
260.
Octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine (HMX) is a toxic explosive known to be resistant to biodegradation. In this study, we found that sediment collected from two unexploded ordnance (UXO) disposal sites (UXO-3, UXO-5) and one nearby reference site (midref) in Hawaii contained anaerobic bacteria capable of removing HMX. Two groups of HMX-removing bacteria were found in UXO-5: group I contained aerotolerant anaerobes and microaerophiles, and group II contained facultative anaerobes. In UXO-3 and midref sediments, HMX-metabolizing bacteria were strictly anaerobic (group III and group IV). Using 16S rRNA sequencing, group I was assigned to a novel phylogenetic cluster of Clostridiales, and groups II and III were related to Paenibacillus and Tepidibacter of Firmicutes, respectively. Group IV bacteria were identified as Desulfovibrio of Deltaproteobacteria. Using [UL-(14)C]-HMX, group IV isolates were found to mineralize HMX (26.8% in 308 d) as determined by liberated (14)CO(2), but negligible mineralization was observed in groups I-III. Resting cells of isolates metabolized HMX to N(2)O and HCHO via the intermediary formation of 1-nitroso-octahydro-3,5,7-trinitro-1,3,5,7-tetrazocine together with methylenedinitramine. These experimental findings suggest that HMX biotransformation occurred either via initial denitration followed by ring cleavage or via reduction of one or more of the N-NO(2) group(s) to the corresponding N-NO bond(s) prior to ring cleavage. 相似文献