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11.
Nickel is a fundamental element for healthy life for human and higher animals. For biological importance, its complexation with bioactive ligand is worth to be studied with the aim to understand its function. Using mouse peritoneal cancer model, MTT colorimetric assay and anticancer activity analysis, we examined the role of nickel(ll) complex in growth inhibition of cancer cells. A novel nickel(ll) complex was synthesized and characterized using physico‐chemical and spectroscopic techniques. The study indicated that both the ligand and complex were capable of inhibiting Ehrlich Ascites Carcinoma (EAC) cells growth by 28.21% and 44.52%, respectively, when administered 0.3 mg/kg/day body weight intraperitoneally for five consecutive days in Swiss Webstar mice. Determination the LD50 of the complex (55 mg/kg) allowed adjusting the dose as 2.75 mg/kg and upon administration, inhibition increased to 69.36%. The ligand and complex have shown an inhibitory effect in the range of 4.86%–67.3% and 6.1%‐ 89.37%, respectively, against EAC cells (concentration range of 31.25–500 μg/ml) in RPMI‐1640 medium as determined by MTT colorimetric assay. Apoptotic cell morphological alteration was determined through optical and fluorescence microscopy. Up regulation of P53, Bax, Cas‐8, Cas‐3 and Fas and down regulation of NF‐kB and Bcl‐2 gene expression were observed in the cells treated with the nickel(ll) complex for five consecutive days. In conclusion, the newly synthesized nickel(ll) complex has shown anti‐proliferative activity and can further be optimized to be used as a lead molecule for anticancer drug.  相似文献   
12.
Trisubstituted quinolines and acylhydrazones were unexpectedly prepared from a reaction of N′-((2-aminophenyl)(phenyl)methylene)benzohydrazides with acetylenic esters. Using of N′-((2-aminophenyl)(phenyl)methylene)benzohydrazides led to obtain not only quinoline, but also a second pharmaceutical important product acylhydrazone. Notably, excellent yields, operational simplicity, short reaction times, and the avoidance of the use of catalysts make this approach an attractive complementary method to produce quinoline-2,3-dicarboxylates. The crystal structure of 5a was determined using single-crystal X-ray crystallography. The results showed that crystal packing diagram of 5a is of two pairs of molecules that have two independent alternate intermolecular 1D-polymeric H-bonds between two perpendicular molecules.  相似文献   
13.
The arrangement of antennal sensilla was studied in female and male ground beetles Bembidion properans Steph. (Coleoptera, Carabidae) using scanning electron microscopy. The filiform antennae, 1.8-1.9 mm in length, consist of the scape, pedicel and nine flagellomeres. In both sexes, three types of sensilla chaetica, two types of sensilla trichodea, six types of sensilla basiconica, one type of sensilla coeloconica and one type of sensilla campaniformia were distinguished. The possible function of the sensilla is discussed and three types of sensilla are considered olfactory, sensilla trichodea type 2 and sensilla basiconica types 1 and 2. Olfactory sensilla form dorsal and/or ventral sensillar fields on the flagellomeres and occur sparsely or not at all outside these areas. No sexual differences in the types, number and distribution of antennal sensilla were found.  相似文献   
14.
A modified Dakin‐West one‐pot, four‐component condensation of an aryl aldehyde, aryl ketone, acetyl chloride and acetonitrile in the presence of silica supported perchloric acid as an active, inexpensive, recoverable and recyclable catalyst is reported for the synthesis of β‐acetamido ketones under mechanical stirring and ultrasonic irradiation conditions. This system has advantages of short reaction times, good to excellent yields and the ability to carry out the large scale reactions. The use of ultrasound increases the rate of reactions compared with reactions at reflux conditions.  相似文献   
15.
Double helices are not common in polypeptides and proteins except in the peptide antibiotic gramicidin A and analogous l,d ‐peptides. In contrast to natural polypeptides, remarkable β‐double‐helical structures from achiral γ‐peptides built from α,β‐unsaturated γ‐amino acids have been observed. The crystal structures suggest that they adopted parallel β‐double helical structures and these structures are stabilized by the interstrand backbone amide H‐bonds. Furthermore, both NMR spectroscopy and fluorescence studies support the existence of double‐helical conformations in solution. Although a variety of folded architectures featuring distinct H‐bonds have been discovered from the β‐ and γ‐peptide foldamers, this is the first report to show that achiral γ‐peptides can spontaneously intertwine into β‐double helical structures.  相似文献   
16.
Daneshfar  Ali  Khezeli  Tahere 《Mikrochimica acta》2015,182(1-2):209-216
Microchimica Acta - A simple, inexpensive and efficient procedure was developed for solid-phase microextraction of nicotine from the headspace above an aqueous sample. A thin layer chromatography...  相似文献   
17.
Limnothrix redekei PUPCCC 116, a filamentous cyanobacterium, has been identified through 16S rRNA gene sequencing. Exopolysaccharides (EPS) of this organism have been isolated and characterized chemically, and its rheological properties were compared with commercial xanthan. The organism produced 304 μg EPS/ml culture in 21 days. The rate of EPS production was maximum (313 μg EPS/mg protein/day) during the initial days of growth, and it decreased to 140 μg EPS/mg protein/day during 18-21 days of growth. Chemical analysis of EPS revealed the presence of glucose/mannose, ribose, rhamnose, and uronic acid. Fourier transformed infrared spectrum of EPS further revealed the presence of methyl and carboxyl groups besides C–N groups indicating the presence of peptidyl moieties. Elemental analysis of EPS showed the presence of 4.97% N. The organism under continuous light produced 102% more EPS compared to when grown under a light/dark cycle of 14/10 h. The rheological properties of EPS were comparable with commercial xanthan gum.  相似文献   
18.
Volatile oil composition of hydro-distilled (HD) and supercritical carbon dioxide (SC-CO(2)) essential oil of freshly collected aerial parts of Heracleum thomsonii (Umbeliferae) from the western Himalayas was studied by GC-FID and GC-MS. Results revealed qualitative and quantitative dissimilarity in the composition of hydro-distilled and SC-CO(2) extracted oils. Nineteen constituents, which accounted for 89.32% of total constituents in HD oil, represented by limonene (4.31%), (Z)-β-ocimene (3.69%), terpinolene (22.24%), neryl acetate (36.19%), nerol (9.51%) and p-cymene-8-ol (2.61%) were identified. In SC-CO(2) extracted oil, 24 constituents representing 89.95% of total constituents were identified. Terpinolene (5.08%), germacrene D (2.17%), neryl acetate (51.62%), nerol (9.78%), geranyl acetate (2.06%), α-bisabolol (2.48%) and 1-nonadecanol (4.96%) were the dominating constituents. In?vitro antimicrobial activity of hydro-distilled oil was conducted against microrobial strains including two Gram-positive (Staphylococcus aureus and Bacillus subtilis) and five Gram-negative (Burkholderia cepacia, Escherichia coli, Enterobacter cloacae, Klebseilla pneumoniae and Pseudomonas aeruginosa) bacteria as well as seven fungi (Candida albicans, Issatchenkia orientalis, Aspergillus flavus, Aspergillus niger, Aspergillus parasiticus, Aspergillus sydowii and Trichophyton rubrum) using broth microdilution method. The results of bioassay showed that the oil exhibited moderate to high antimicrobial activity against fungi C. albicans (MIC 625 μg?ml(-1)), A. parasiticus (MIC 312.5 μg?ml(-1)), A. sydowii (MIC 312.5 μg?ml(-1)), T. rubrum (MIC 625 μg?ml(-1)), Gram-positive bacteria B. subtilis (MIC 625?μg?ml(-1)) and Gram-negative bacteria P. aeruginosa (MIC 312.5 μg?ml(-1)).  相似文献   
19.
In the field of coatings, extensive laboratory research has been conducted in the last decade. In the present work, effectiveness of epoxy resin filled micro/nanocapsules was investigated for future using in healing of cracks generated in coatings. Micro/nanocapsules were prepared by in situ polymerization of urea–formaldehyde resin to form shell over epoxy resin droplets. The optimal process parameters for synthesizing the micro/nanocapsules were selected. The as-synthesized capsules were studied by various characterizations techniques, including scanning electron microscope (SEM), particle size analyzer (PSA), Fourier transform-infrared spectroscopy (FTIR), thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC). The results indicate that micro/nanocapsules containing epoxy resins can be synthesized successfully. The rough outer surface of microcapsule is composed of agglomerated urea–formaldehyde nanoparticles. They basically exhibit good storage stability at room temperature, and they are chemically stable before the heating temperature is up to approximately 250°C.  相似文献   
20.
A new technique is presented for making measurements of the instantaneous flow rate in unsteady laminar pipe flows. It utilizes a relationship between flow rate and pressure-gradient history that is an exact solution to the Navier–Stokes equations for parallel, developed flow of constant-property Newtonian fluids undergoing arbitrary unsteadiness from an initially steady or stationary state. The method does not rely on any assumption about velocity profiles, and applies instantaneously in momentarily reversing flow. Experimental comparisons between direct measurements of the cumulative flow and the results of this technique indicate that it is capable of providing measurements of cumulative flow and flow rate which are accurate to within a few percent at any instant during a flow transient, provided the instantaneous pressure gradient can be measured with this accuracy.  相似文献   
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