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991.
992.
A chiral enantioseparation generic strategy for anti‐Alzheimer and antifungal drugs by short end injection capillary electrophoresis using an experimental design approach 下载免费PDF全文
The present study describes a generic strategy using capillary electrophoretic (CE) method for chiral enantioseparation of anti‐Alzheimer drugs, namely, donepezil (DON), rivastigmine (RIV), and antifungal drugs, namely, ketoconazole (KET), Itraconazole (ITR), fluconazole (FLU), and sertaconazole (SRT) in which these drugs have different basic and acidic properties. Several modified cyclodextrins (CDs) were applied for enantioseparation of racemates such as highly sulfated α, γ CDs, hydroxyl propyl‐β‐CD, and Sulfobutyl ether‐β‐CD. The starting screening conditions consist of 50‐mM phosphate‐triethanolamine buffer at pH 2.5, an applied voltage of 15 kV, and a temperature of 25°C. The CE strategy implemented in the separation starts by screening prior to the optimization stage in which an experimental design is applied. The design of experiment (DOE) was based on a full factorial design of the crucial two factors (pH and %CD) at three levels, to make a total of nine (32) experiments with high, intermediate, and low values for both factors. Evaluation of the proposed strategy pointed out that best resolution was obtained at pH 2.5 for five racemates using low percentages of HS‐γ‐CD, while SBE‐β‐CD was the most successful chiral selector offering acceptable resolution for all the six racemates, with the best separation at low pH values and at higher %CD within 10‐min runtime. Regression study showed that the linear model shows a significant lack of fit for all chiral selectors, anticipating that higher orders of the factors are most likely to be present in the equation with possible interactions. 相似文献
993.
Gholam Reza Ghezelbash Maryam Haddadi 《World journal of microbiology & biotechnology》2018,34(12):174
Cementation of salt-containing soils can be achieved by salt-tolerant or halophilic calcite precipitation bacteria. Therefore, the isolation of calcite-producing bacteria in the presence of salt is the first step in the microbial cementation of saline soils. Urease producing bacteria can cause calcite nano-crystals to precipitate by producing urease in the presence of urea and calcium. The purpose of this study was to isolate urease producing halophilic bacteria in order to make calcite precipitate in saline soil. The calcite and the properties of the strains were further analyzed by X-ray diffraction (XRD) and scanning electron microscope equipped with an energy dispersive X-ray detector. In this study, a total of 110 halophilic strains were isolated, from which 58 isolates proved to have the ability of urease production. Four strains were identified to produce nano-calcite using urease activity in the precipitation medium. The XRD studies showed that the size of these particles was in the range of 40–60 nm. Strain H3 revealed that calcite is mostly produced in the precipitation medium containing 5% salt in comparison with other strains. This strain also produced calcite precipitates in the precipitation medium containing 15% salt. Phylogenetic analysis indicated that these isolates are about 99–100% similar to Staphylococcus saprophyticus. 相似文献
994.
995.
Osama Omar Yousif Mea’ad Kadhum Hassan Lamia Mustafa Al-Naama 《Biological trace element research》2018,182(2):295-302
This study investigated neurotoxicity of chronic fluorosis in the rat hippocampus. Newly weaning, male, Sprague-Dawley (SD) rats were administered 15, 30, and 60 mg/L sodium fluoride (NaF) solution (fluorine ion concentration 8.25, 16.50, and 33.00 mg/L, respectively), and tap water, for 18 months. The neurotoxicological mechanism was examined with a focus on intracellular calcium overload. Results showed that as the fluoride concentration increased, calcium ion concentration [Ca2+], the expression of calcium/calmodulin-dependent protein kinase II α (CaMKIIα), and the expression of catus proto-oncogene protein c-fos (c-fos) all tend to increase. Compared to the control group, Ca2+, CaMKIIα, and c-fos significantly increased (P < 0.05) in the moderate-fluoride and the high-fluoride groups. These results indicate that Ca2+/CaMKIIα/c-fos channel signal may be the molecular mechanism of central nervous system damage caused by chronic fluoride intoxication. Moreover, elevated Ca2+ concentration in the hippocampus may be the initiating factor of neuronal apoptosis induced by fluoride. 相似文献
996.
Masoume Zeinipour Pejman Azadi Ahmad Majd Maryam Jafarkhani Kermani Saeed Irian Seyed Mohammad Hosseini Masahiro Mii 《Physiology and Molecular Biology of Plants》2018,24(3):503-511
Rose cultivars with blue flower color are among the most attractive breeding targets in floriculture. However, they are difficult to produce due to the low efficiency of transformation systems, interactive effects of hosts and vectors, and lengthy processes. In this study, agroinfiltration-mediated transient expression was investigated as a tool to assess the function of flower color genes and to determine appropriate host cultivars for stable transformation in Rosa hybrida. To induce delphinidin accumulation and consequently to produce blue hue, the petals of 30 rose cultivars were infiltrated with three different expression vectors namely pBIH-35S-CcF3′5′H, pBIH-35S-Del2 and pBIH-35S-Del8, harbouring different sets of flower color genes. The results obtained showed that the ectopic expression of the genes was only detected in three cultivars with dark pink petals (i.e. ‘Purple power’, ‘High & Mora’ and ‘Marina’) after 6–8 days. The high performance liquid chromatography analyses confirmed delphinidin accumulation in the infiltrated petals caused by transient expression of CcF3′5′H gene. Moreover, there were significant differences in the amounts of delphinidin among the three cultivars infiltrated with the three different expression vectors. More specifically, the highest delphinidin content was detected in the cultivar ‘Purple power’ (4.67 µg g?1 FW), infiltrated with the pBIH-35S-Del2 vector. The expression of CcF3′5′H gene in the infiltrated petals was also confirmed by real time PCR. In conclusion and based on the findings of the present study, the agroinfiltration could be regarded as a reliable method to identify suitable rose cultivars in blue rose flower production programs. 相似文献
997.
Capparis spinosa L. (caper bush) is an economically and ecologically important perennial shrub that grows across different regions of Iran. In this study, the genetic diversity and population structure of Iranian genepool of C. spinosa is evaluated using Inter Simple Sequence Repeat (ISSR) markers. Using 10 ISSR primers, 387 DNA fragments (bands) were amplified from the genomic DNA of 92 individuals belonging to twenty-one populations of C. spinosa, of which 378 (97.7%) were polymorphic. High level of genetic diversity (percentage of polymorphic loci = 98.2%, h = 0.1382, I = 0.243), high genetic differentiation (Gst = 0.5234) and low gene flow (Nm = 0.4553) among populations were observed. Caper bush populations were divided into 4 groups in the dendrogram, PCoA plot and Bayesian clustering results, mostly corresponded to their geographic regions. The results showed that there are value in sampling Iranian caper bush populations to look for valuable alleles for use in plant breeding programs. 相似文献
998.
Shyam Sreedhara Kurup Fayas Thayale Purayil Mubarak Mohammed Sultan Alkhaili Nadia Hassan Tawfik Abdul Jaleel Cheruth Maher Kabshawi Sreeramanan Subramaniam 《Physiology and Molecular Biology of Plants》2018,24(4):683-692
Haloxylon persicum (Bunge ex Boiss & Buhse), is one of the hardy woody desert shrubs, which is now endangered and/or nearing extinction. Urban landscape development and overgrazing are the major threats for the erosion of this important plant species. For conserving the species, it is critical to develop an efficient in vitro regeneration protocol for rapid multiplication of large number of regenerants. Leaf explants, cultured on Murashige and Skoog (MS) medium supplemented with different concentrations of thidiazuron (TDZ) (0.5, 1, 2 µM), showed significant difference in bud sprouting and adventitious shoot induction. The highest shoot bud formation was recorded on MS medium supplemented with 0.5 µM TDZ. Shoot tip necrosis (STN), observed after first subculture of shoot buds in same medium, increased in severity with subculture time. Application of calcium (4 mM) and boron (0.1 mM) in combination with kinetin (10 µM) in the subculture medium significantly reduced the intensity of STN. On an average eight shoots/explant were produced by alleviating this problem. ISSR marker analysis revealed monomorphic banding pattern between progenies and parents, indicating the true to type nature of the clones and its parents. 相似文献
999.
Muhammad Athar Abbasi Mubashir Hassan Sabahat Zahra Siddiqui Hussain Raza Syed Adnan Ali Shah Sung-Yum Seo 《Bioorganic & medicinal chemistry》2018,26(13):3791-3804
The present article describes the synthesis, in vitro urease inhibition and in silico molecular docking studies of a novel series of bi-heterocyclic bi-amides. The synthesis of title compounds was initiated by benzoylation, with benzoyl chloride (1), of the key starter ethyl 2-(2-amino-1,3-thiazol-4-yl)acetate (2) in weak basic aqueous medium followed by hydrazide formation, 4, and cyclization with CS2 to reach the parent bi-heterocyclic nucleophile, N-{4-[(5-sulfanyl-1,3,4-oxadiazol-2-yl)methyl]-1,3-thiazol-2-yl}benzamide (5). Various electrophiles, 8a–l, were synthesized by a two-step process and these were finally coupled with 5 to yield the targeted bi-heterocyclic bi-amide molecules, 9a–l. The structures of the newly synthesized products were corroborated by IR, 1H NMR, 13C NMR, EI-MS and elemental analysis. The in vitro screening of these molecules against urease explored that most of the compounds exhibit potent inhibitory potential against this enzyme. The compound 9j, with IC50 value of 2.58?±?0.02?µM, exhibited most promising inhibitory activity among the series, relative to standard thiourea having IC50 value of 21.11?±?0.12?µM. In silico studies fully augmented the experimental enzyme inhibition results. Chemo-informatics analysis showed that synthesized compounds (9a–l) mostly obeyed the Lipinski's rule. Molecular docking study suggested that ligand 9j exhibited good binding energy value (?7.10?kcal/mol) and binds within the active region of target protein. So, on the basis of present investigation, it was inferred that 9j may serve as a novel scaffold for designing more potent urease inhibitors. 相似文献
1000.
Aamer Saeed Gufran Saddique Pervaiz Ali Channar Fayaz Ali Larik Qamar Abbas Mubashir Hassan Hussain Raza Tanzeela Abdul Fattah Sung-Yum Seo 《Bioorganic & medicinal chemistry》2018,26(12):3707-3715
To seek the new medicinal potential of sulfadiazine drug, the free amino group of sulfadiazine was exploited to obtain acyl/aryl thioureas using simple and straightforward protocol. Acyl/aryl thioureas are well recognized bioactive pharmacophore containing moieties. A new series (4a–4j) of sulfadiazine derived acyl/aryl thioureas was synthesized and characterized through spectroscopic and elemental analysis. The synthesized derivatives 4a–4j were subjected to calf intestinal alkaline phosphatase (CIAP) activity. The derivative 4a–4j showed better inhibition potential compared to standard monopotassium phosphate (MKP). The compound 4c exhibited higher potential in the series with IC50 0.251?±?0.012?µM (standard KH2PO4 4.317?±?0.201?µM). Lineweaver-Burk plots revealed that most potent derivative 4c inhibition CIAP via mixed type pathway. Pharmacological investigations showed that synthesized compounds 4a–4j obey Lipinsk’s rule. ADMET parameters evaluation predicted that these molecule show significant lead like properties with minimum possible toxicity and can serve as templates in drug designing. The synthetic compounds show none mutagenic and irritant behavior. Molecular docking analysis showed that compound 4c interacts with Asp273, His317 and Arg166 amino acid residues. 相似文献