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161.
International Journal of Peptide Research and Therapeutics - Lipopeptide biosurfactants (LPBs) display unique properties with widespread therapeutic applications. Recently, the wound healing...  相似文献   
162.
A sensitive and rapid high-performance liquid chromatographic method for the analysis of fluvoxamine, a selective serotonin reuptake inhibitor in human serum, is described using 4-chloro-7-nitrobenzofurazan as pre-column derivatization agent. The drug and an internal standard (fluoxetine) were extracted from 0.25 mL of serum using ethyl acetate as extracting solvent and subjected to pre-column derivatization by the reagent. A mobile phase consisting of methanol and sodium phosphate buffer (0.05 M; pH 2.8) containing 1 mL/L triethylamine (72:28 v/v) was used and chromatographic separation was performed on a Shimpack CLC-C18 (150 mm x 4.6mm) column. The fluorescence derivatives of the drugs were monitored at excitation and emission wavelengths of 470 and 537 nm, respectively. The calibration curve was linear over the concentration range of 0.5-240 ng/mL with a limit of quantification (LOQ) of 0.5 ng/mL using 0.25 mL serum sample. The method validation was performed for its selectivity, specificity, sensitivity, precision and accuracy. In this method, which was applied in a randomized cross-over bioequivalence study of two different fluvoxamine preparations in 24 healthy volunteers, the sensitivity and run time of analysis were significantly improved.  相似文献   
163.
Plant diseases have a significant impact on the yield and quality of crops. Many strategies have been developed to combat plant diseases, including the transfer of resistance genes to crops by conventional breeding. However, resistance genes can only be introgressed from sexually-compatible species, so breeders need alternative measures to introduce resistance traits from more distant sources. In this context, genetic engineering provides an opportunity to exploit diverse and novel forms of resistance, e.g. the use of recombinant antibodies targeting plant pathogens. Native antibodies, as a part of the vertebrate adaptive immune system, can bind to foreign antigens and eliminate them from the body. The ectopic expression of antibodies in plants can also interfere with pathogen activity to confer disease resistance. With sufficient knowledge of the pathogen life cycle, it is possible to counter any disease by designing expression constructs so that pathogen-specific antibodies accumulate at high levels in appropriate sub-cellular compartments. Although first developed to tackle plant viruses and still used predominantly for this purpose, antibodies have been targeted against a diverse range of pathogens as well as proteins involved in plant–pathogen interactions. Here we comprehensively review the development and implementation of antibody-mediated disease resistance in plants.  相似文献   
164.
Barley, Hordeum vulgare, one of the important crops in the word, is used in malting, feed and food industries. The red flour beetle, Tribolium castaneum, was found wherever grains or other dried foods are stored. Disinfestations of barley using chemical methods to kill insects, in this research, for the first time we isolated the pathogenic KB512 of entomopathogenic fungi Beauveria bassiana from soil and insects, which produced aerial and submerged conidia and blastospores in laboratory conditions. We investigated the best conditions for the production and utilisation of spore suspension to spray the larvae of T. castaneum, which is one of the important pests in Kerman province (Iran). One hundred and eighty isolates that naturally infected by T. castaneum were reared during spring and summer seasons 2010–2011. The pathogenicity test was carried out with direct spray. To bioassay the isolates, three concentrations of the spore suspension were prepared as follows: 1?×?106 and 1?×?108 conidia/ml. The pests were sprayed by aerial conidial suspension, which was prepared by 0.01% Tween 80 in distilled water, and the controls were sprayed by 0.01% Tween 80 in distilled water. After spraying the pests, the plates were incubated at 25?±?1?°C and 80% of relative humidity. Then, the treated pests were monitored every day for the fungal growth and mortality.  相似文献   
165.
Systematic Parasitology - One new and three known species of the genus Xiphinema from the rhizosphere of fruit trees and rose shrubs in East Azarbaijan province, Iran, are presented based on the...  相似文献   
166.
Exposure to severe and long-lasting stressors during early postnatal life negatively affects development of the brain and associated biological networks. Maternal separation (MS) is a valid stressful experience in early life that adversely affects neurobiological circuits. In the present study, we aimed to evaluate the effects of MS on sperm quality and histology of the testis in adult male mice. In this study, male mice were subjected to MS during post-natal days (PND) 2–14. Sperm parameters, histological alterations in the testicular tissue, ROS production (using DCFH-DA assay), gene expression of TLR4, NLRP3, TNFα, BAX, ASC, caspase-1 and BCL-2 (using RT-PCR), protein levels of caspase-3 and caspase-8 (using western blotting), and protein levels of IL-1β, IL-18, GPx and ATP (using ELISA) as well as protein expression of caspase-1 and NLRP3 (using immunocytochemistry) were evaluated. Findings showed that MS decreased count, morphology and viability of spermatozoa. MS decreased the diameter of seminiferous tubules and decreased the thickness of seminiferous epithelium. Furthermore, MS increased the level of ROS production and decreased the concentrations of GPx and ATP. MS led to increased expression of TLR4, NlRP3, TNFα, caspase-1, ASC, IL-1β and IL-18. In addition, MS induced apoptosis as evidenced by increased BAX, caspase-3 and caspase-8 as well as decreased BCL-2 expression. We concluded that early life stress induced by MS has detrimental effects on sperm parameters and testicular tissue. Our results suggest that these effects are mediated by activation of ROS production, and alterations in mitochondrial function, inflammatory processes and apoptosis pathways.  相似文献   
167.
Glibenclamide (GB), as a sulfonylurea‐based medication is commonly prescribed for the treatment of type 2 diabetes. Due to its increasing consumption, there is a need to develop a simple, fast, and reliable detection method to follow its concentration in pharmaceutical and biological samples. Herein, a novel fluorometric method is developed for the sensitive measurement of GB. The method is based on the enhancing effect of GB on the fluorescence emission of mercaptopropionic acid (MPA) capped cadmium telluride quantum dots (CdTe QDs). QDs were synthesized in aqueous solution and were characterized by fluorescence spectroscopy, transmission electron microscopy (TEM), X‐ray diffraction (XRD) and Fourier transform infrared spectroscopy (FT‐IR). Fluorescence intensity of QDs was enhanced by adding GB in a very low concentration. The effect of operative factors such as pH, buffer, contact time and concentration of CdTe QDs were investigated and in the optimized condition, a linear increase was achieved for the emission intensity of QDs by increasing GB concentration in the range 49–345 ng mL?1, with a detection limit of 17.84 ng mL?1. The offered method has an acceptable precision (relative standard deviations were < 2.8%) and was satisfactorily applied for the determination of GB in pharmaceutical products and human urine samples.  相似文献   
168.
Sodium nitroprusside (SNP) and hydrogen peroxide (H2O2), as priming agents, have the well-recorded property to increase plant tolerance against a range of different abiotic stresses such as salinity. In this regard, the present study was conducted to evaluate the effect of different levels of SNP (100 and 200 µM) and H2O2 (2.5 and 5 mM) as well as their combinations under salt stress (0 and 50 mM NaCl) on key physiological and biochemical attributes of the economically important aromatic plant basil (Ocimum basilicum L.) grown under hydroponic culture. Results revealed that morphological parameters such as plant height, root length, leaf fresh and dry weights (FW and DW) were significantly decreased by salinity stress, while SNP and H2O2 treatments, alone or combined, increased FW and DW thus enhancing plant tolerance to salt stress. Furthermore, 200 µM SNP + 2.5 mM H2O2 appeared to be the most effective treatment by causing significant increase in chlorophyll a and b, anthocyanin content and guaiacol peroxidase and ascorbate peroxidase enzymes activities under saline condition. In addition, analytical measurements showed that essential oil profile (concentration of main components) under salt stress was mostly affected by SNP and H2O2 treatments. The highest increase was observed for methyl chavicol (43.09–69.91%), linalool (4.8–17.9%), cadinol (1.5–3.2%) and epi-α-cadinol (0.18–10.75%) compounds. In conclusion, current findings demonstrated a positive crosstalk between SNP and H2O2 toward improved basil plant tolerance to salt stress, linked with regulation of essential oil composition.  相似文献   
169.
Molecular Biology Reports - Managing&nbsp;tendon healing process is complicated mainly due to&nbsp;the limited regeneration capacity of tendon tissue. Mesenchymal stem cells (MSCs) have...  相似文献   
170.
The present study describes a rapid and sensitive high-performance liquid chromatography (HPLC) method for the detection of human globin chains in blood. The method involves direct injection of globin chains which prepared by a standard method onto a micro bondapack C18 reversed-phase column (7.8 mm I.D.) with UV detection at 280 nm. The detection limit of hemoglobin (Hb) was 0.1 μg, which is equivalent to about 1 ml of fresh whole blood. We report here the rapid procedure for globin chain analysis. The present method will be useful for the determination of globin chain analysis in clinical laboratories, as well as in thalassemia and sickle cell disease patients.  相似文献   
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