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71.
72.
Molecularly imprinted nano-particles (MINPs) selective for olanzapine were prepared using methacrylic acid (MA) as monomer, ethylene glycol dimethacrylate (EGDMA) as a cross-linker, and 2,2-azobis (2-isobutyronitrile) (AIBN) as the initiator in 36 different ratios. The reaction runs with considerable fine powder formation were selected for further binding and selectivity studies. The MINP with the best selectivity (MINP-32) was chosen for further structural characterization by Fourier transform infrared spectroscopy (FT-IR), thermal gravimetric analysis (TGA), scanning electron microscopy (SEM), adsorption-desorption isotherm for specific surface area, volume and average pore diameter determination. All characterization methods confirmed the successful formation of MINP. The optimum conditions for maximum template loading on the MINP-32 were found by experimental design using response surface methodology (RSM) and choosing absorbent amount, pH, and time as the main factors. MINPs with maximum template loading also indicated significant selectivity between template and its analog (clozapine). The release profile demonstrated a maximum release of about 95% after 288 h for MINP-32 in comparison with about 94% after 120 h for non-MINP-32. The same slow release of drug from MINP-32 was also observed during animal study of the plasma level of template, 20–28 μg/ml versus 5–10 μg/ml. The MINP-32 of this study represents a desirable ability to keep the memory of the template with significant selectivity and good capability to control the release of template in vitro and in vivo and hence could be a promising drug delivery system.  相似文献   
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74.
BackgroundTo investigate dose distribution of the 5cm spherical applicator of the INTRABEAM™ intraoperative radiation therapy (IORT) device via thermoluminescence dosimeters (TLDs) and Radiographic films. Independent dose distribution assessment of IORT devices is considered important. Several methods are described for this purpose, including TLDs and films. However, Radiographic films are not routinely used.Materials and methodsTwenty TLDs were used for depth dose measuring and evaluating the isotropy in water. Additionally, the isotropy was assessed separately via Radiographic films in air by drawing isodose curves.ResultsTLD measurements showed a steep dose decline which the relative average dose of 0.94 at the applicator surface reduced to 0.32, 0.13, and 0.07 at 1, 2, and 3 cm depths in water, respectively. Some remarkable isodose curves prepared using Radiographic films showed forward anisotropy of the 5 cm applicator.ConclusionA very steep dose decline and approximately isotropic dose distribution of the 5 cm applicator were observed via TLD measurements. Radiographic films showed acceptable potential for drawing dose distribution maps. However, they should be applied in more various radiation setups to be implemented more confidently.  相似文献   
75.
Five dissymmetric tridentate Schiff base ligands, containing a mixed donor set of ONN and ONO were prepared by the reaction of benzhydrazide with the appropriate salicylaldehyde and pyridine-2-carbaldehyde and characterized by FT-IR, 1H and 13C NMR. The complexes of these ligands were synthesized by treating an ethanolic solution of the appropriate ligand and one equivalent Et3N with an equimolar amount of MnCl2 · 4H2O or alternatively by a more direct route in which an ethanolic solution of benzhydrazide was added to ethanolic solution of appropriate salicylaldehyde and MnCl2 · 4H2O solution to yield [MnCl(L1)(H2O)2], [Mn(L2)2(H2O)2], [MnCl(L3)], [MnCl(L4)] and [MnCl2(H2O)(L5)]. The hydrazone Schiff base ligands and their manganese complexes including HL1-4 and L5 (HL1 = benzoic acid (2-hydroxy-3-methoxy-benzylidene)-hydrazide, HL2 = benzoic acid (2,3-dihydroxy-benzylidene)-hydrazide, HL3 = benzoic acid (2-hydroxy-benzylidene)-hydrazide, HL4 = benzoic acid (5-bromo-2-hydroxy-benzylidene)-hydrazide, L5 = benzoic acid pyridine-2-yl methylene-hydrazide) were characterized on the basis of their FT-IR, 1H and 13C NMR, and molar conductivity. The crystal structures of HL1 and [MnCl2(H2O)L5] have been determined. The results suggest that the Schiff bases HL1, HL2, HL3, and HL4 coordinate as univalent anions with their tridentate O,N,O donors derived from the carbonyl and phenolic oxygen and azomethine nitrogen. L5 is a neutral tridentate Schiff base with N,N,O donors. ESI-MS for the complexes Mn-L2,3,5 provided evidence for the presence of multinuclear complexes in solution. Catalytic ability of Mn-L1-5 complexes were examined and found that highly selective epoxidation (>95%) of cyclohexene was performed by iodosylbenzene in the presence of these complexes and imidazole in acetonitrile.  相似文献   
76.
Augmentation of mitochondrial oxidative stress through activating a series of deadly events has implicated as the main culprit of arsenic toxicity and therapeutic approaches based on improving mitochondrial function hold a great promise for attenuating the arsenic-induced toxicity. Acetyl-l-carnitine (ALC) through balancing the coenzyme A (CoA)/acyl-CoA ratio plays an important role in mitochondrial metabolism and thereby can help protect hippocampal neurons from oxidative damage. In the present study, we aimed to explore the effect of arsenic interactions on the mitochondrial function in the hippocampus of rats. Rats were randomly divided into five groups of control (distilled water), sodium arsenite (NaAsO2, 20 mg/kg), and co-treatment of NaAsO2 with various doses of ALC in three groups (100, 200, 300 mg/kg) and were treated orally for 21 consecutive days. Our results point out that arsenic exposure caused oxidative stress in rats’ hippocampus, which led to the reactive oxygen species (ROS) generation, mitochondrial swelling, the collapse of the mitochondrial membrane potential, and release of cytochrome c. It also altered Bcl-2/Bax expression ratio and increased caspase-3 and caspase-9 activities. Furthermore, arsenic exposure via activation of NF-κB and microglia increased inflammation. ALC could concentration-dependently counteract the arsenic-induced oxidative stress, modulate the antioxidant defense capacity, and improve mitochondrial functions. In addition, ALC decreased the expression of both death-associated proteins and of inflammatory markers. These findings indicate that ALC improved the arsenic-induced hippocampal mitochondrial dysfunction which underlines the importance of ALC in providing a possible therapeutic strategy for the prevention of arsenic-induced neurodegeneration.  相似文献   
77.
DMD gene which is composed of 79 exons is the largest known gene located on X chromosome (Xp21). Point mutations in the dystrophin gene are responsible for 30–35% of cases with DMD/BMD. Mutation analysis of all the exons of the DMD gene is costly in developing countries, therefore, a few of the exons are selected to be analyzed routinely in clinical laboratories. In this study, direct sequencing was used for detection of point mutations in 10 exons of dystrophin gene in patients affected with DMD without detectable large rearrangements. Freely available programs were used to predict the damaging effects of the mutations. Point mutations were successfully detected in three patients. Three novel mutations, two missense mutations located on nonconservative domains and a single nucleotide deletion, were detected. Missense mutations were predicted to change splicing efficiency. Detection of point mutations by DNA analysis followed by prediction of the pathogenecity by using bioinformatic tool might be an asset to provide proper diagnosis or genetic counseling to patients and their family.  相似文献   
78.
This paper report on a new species of mites of the genus Myrmozercon associated with ant in Iran – Myrmozercon cyrusi Ghafarian and Joharchi sp. n. was collected associated of the Monomorium sp. in Kenevist Rural District in the Central District of Mashhad County, Khorasan Razavi Province, Iran. This new species is described and illustrations provided. Myrmozercon ovatum Karawajew, 1909 is suspected to be a junior synonym of Myrmozercon brevipes Berlese, 1902 and host-specificity and host range of Myrmozercon are also reviewed.  相似文献   
79.
Cell competition where ‘loser’ cells are eliminated by neighbors with higher fitness is a widespread phenomenon in development. However, a growing body of evidence argues cells with somatic mutations compete with their wild type counterparts in the earliest stages of cancer development. Recent studies have begun to shed light on the molecular and cellular mechanisms that alter the competitiveness of cells carrying somatic mutations in adult tissues. Cells with a ‘winner’ phenotype create clones which may expand into extensive fields of mutant cells within normal appearing epithelium, favoring the accumulation of further genetic alterations and the evolution of cancer. Here we focus on how mutations which disrupt the Notch signaling pathway confer a ‘super competitor’ status on cells in squamous epithelia and consider the broader implications for cancer evolution.  相似文献   
80.
This study was carried out to evaluate the binding interaction of gefitinib (GEF) with human serum albumin (HSA) and calf thymus DNA (ct-DNA) using fluorescence, UV–Visible, zeta potential measurements and molecular docking methods in order to understand its pharmacokinetic mechanism. By increasing the temperature, a steady decrease in Stern–Volmer quenching constants was observed for HSA binding properties; this indicates a static type of fluorescence quenching. Negative values were calculated for Gibbs free energy (ΔG), enthalpy (ΔH), and entropy (ΔS) changes, indicating that the reaction is spontaneous and enthalpy-driven. Probe competitive experimental results showed that GEF contains the same binding site as warfarin and are consistent with modeling results. The zeta potential of the HSA increased with increasing GEF, which represents the presence of electrostatic interactions in the system. DNA binding properties were investigated in the presence of three probes. The experimental results showed that by increasing GEF to DNA-AO (acridine-orange) and DNA-MB (methylene-blue) system, the fluorescence intensity and absorbance spectra had no considerable change. Furthermore, with the addition of GEF to DNA, the zeta potential decreased gradually, indicating that the hydrophobic interaction between the GEF and the bases of DNA is the major factor. Thus, GEF can bind to DNA via a groove binding mode. It was also found that GEF entered into the minor groove in the A–T rich region of DNA fragment and bind via van der-Waals forces and three H-bond with double strands of DNA. This is in good agreement with experimental results.  相似文献   
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