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131.
132.
Schiff base ligand (L) was obtained by condensation reaction between 4-aminopyrimidin-2(1H)-one (cytosine) with 2-hydroxybenzaldehyde. The synthesized Schiff base was used for complexation with Cu(II) and Fe(II) ions used by a molar (2 : 1 mmol ration) in methanol solvent. The structural features of ligand, Cu(II), and Fe(II) metal complexes were determined by standard spectroscopic methods (FT-IR, elemental analysis, proton and carbon NMR spectra, UV/VIS, and mass spectroscopy, magnetic susceptibility, thermal analysis, and powder X-ray diffraction). The synthesized compounds (Schiff base and its metal complexes) were screened in terms of their anti-proliferative activities in U118 and T98G human glioblastoma cell lines alone or in combination with electroporation (EP). Moreover, the human HDF (human dermal fibroblast) cell lines was used to check the bio-compatibility of the compounds. Anti-proliferative activities of all compounds were ascertained using an MTT assay. The complexes exhibited a good anti-proliferative effect on U118 and T98G glioblastoma cell lines. In addition, these compounds had a negligible cytotoxic effect on the fibroblast HDF cell lines. The use of compounds in combination with EP significantly decreased the IC50 values compared to the use of compounds alone (p<0.05). These results show that newly synthesized Cu(II) and Fe(II) complexes can be developed for use in the treatment of chemotherapy-resistant U118 and T98G glioblastoma cells and that treatment with lower doses can be provided when used in combination with EP.  相似文献   
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The effect of glutamine on radiation-induced organ damage   总被引:4,自引:0,他引:4  
Radiation enteritis is a significant clinical problem in patients receiving ionizing radiation directed to the abdomen or pelvis. Although radiation is aimed to be directed against the malignant tissue, adjacent healthy tissues are also affected. The small intestine is the most sensitive organ to radiation. The present study was undertaken to investigate the possible protective effect of glutamine against radiation-induced intestinal, hepatic and pancreatic toxicity. Rats received 1 g/kg/day glutamine for seven days before irradiation and continued for three days after irradiation until sacrifice. Then intestinal, pancreatic and hepatic myeloperoxidase (MPO) activities, malondialdehyde (MDA) levels and caspase-3 activities of the sacrificed rats were measured. Irradiation significantly increased the intestinal and pancreatic MPO and caspase-3 activities and MDA levels in comparison to sham group. Glutamine treatment significantly decreased this elevation. Histopathological examination revealed that the intestinal mucosal structure was preserved and pancreatic inflammation decreased in the glutamine treated group. In irradiation group, NF-kappaB over expression was detected. There was no significant difference in histopathological and biochemical examinations of the liver between the groups. In conclusion, glutamine has beneficial effects on intestinal and pancreatic damage in abdominal irradiation through the inflammatory process and apoptosis.  相似文献   
135.
The role of epidermal growth factor (EGF), a polypeptide containing 53 amino acids, on protection and repair of ethanol-induced gastric mucosal injury was investigated in rats. In addition, the effects of EGF on the gastric damage were evaluated histopathologically. We used 48 Spraque-Dawley rats which were divided into [corrected] three groups as control rats, ethanol treated rats and ethanol+EGF treated rats. The ethanol group was given a gastric gavage containing 1 ml of 80% ethanol (v/v) prepared in distilled water. EGF (100 microg/kg) was given by intragastric gavage 30 min before the administration of ethanol. We studied histopathological evaluation and the histochemical heterogeneity of mast cells and its degree of degranulation. Besides, gastric tissue malondialdehyde (MDA), protein sulfhydryl groups (SH), and protein carbonyl levels were measured. EGF treatment stabilized mast cells degranulation and had lower polymorphonuclear leukocytes (PMNL) infiltration, ulcer index, histamine, and MDA; protein carbonyl levels were also lower, compared to the non-treated animals. EGF exerts a protective effect on gastric mucosa to ethanol-induced gastric injury probably through antioxidant and mast cell stabilizing mechanism.  相似文献   
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137.
Length–weight and length–length relationships are presented for four freshwater fish species [Liza abu (Heckel, 1843), Aphanius mento (Heckel, 1843), Oxynoemacheilus hamwii (Krupp & Schneider, 1991) and Chondrostoma kinzelbachi Krupp, 1985] captured in Gölba?? Lake, Hatay, Anatolia. No information regarding length–weight relationships was reported previously in FishBase for C. kinzelbachi, A. mento and O. hamwii. Specimens were obtained from January to May 2012 using electrofishing and cast nets. This study presents the first study on LWR data for C. kinzelbachi, A. mento and O. hamwii.  相似文献   
138.
Context: Dilated cardiomyopathy (DCM) is the most common cardiomyopathy in children. MicroRNAs (miRNA) are small RNAs which have regulatory functions in many biological processes.

Objective: We aimed to determine miRNA expression levels in plasma of children with DCM.

Materials and methods: Plasma expression levels of 379 miRNAs were compared between 23 DCM and 26 healthy children.

Results: The expression levels of miR-618, miR-875-3p, miR-205, miR-194, miR-302a, miR-147, and miR-544 were found decreased. The expression levels of miR-518f and miR-454 were found increased in DCM patients.

Discussion: miRNA level differences may provide the chance of using these miRNAs as new biomarkers.  相似文献   
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Recent determination of the molecular structures of potassium andmechanosensitive channels from x-ray crystallography has led to arenewed interest in ion channels. The challenge for permeation modelsis to understand the functional properties of channels from the availablestructural information. Here we give a critical review of the three maincontenders, namely, continuum theories, Brownian dynamics and moleculardynamics. Continuum theories are shown to be invalid in a narrow channel environment because they ignore the self-energy of ions arising from theinduced charges on the dielectric boundary. Brownian and moleculardynamics are thus the only physically valid methods for studying thestructure-function relations in ion channels. Applications of thesemethods to potassium and calcium channels are presented, which illustratethe multi-ion nature of the permeation mechanism in selective biologicalchannels.  相似文献   
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