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101.
Abd-Allah AR Al-Majed AA Mostafa AM Al-Shabanah OA Din AG Nagi MN 《Journal of biochemical and molecular toxicology》2002,16(5):254-259
Arabic gum (AG) is a naturally occurring compound that has been proposed to possess potent antioxidant activity. In this study, the possible effects whereby AG could protect against cardiotoxicity induced by doxorubicin (DOX) in mice were carried out. Administration of single dose of DOX (15 mg/kg, i.p.) induced cardiotoxicity 72 h, manifested biochemically by a significant elevation of serum creatine kinase (CK) (EC 2.7.3.2). In addition, cardiotoxicity was further confirmed by the significant increase in lipid peroxides measured as malondialdehyde (MDA). Administration of AG (25 g/kg) orally for 5 days before and 72 h after DOX injection produced a significant protection against cardiotoxicity induced by DOX. This was evidenced by significant reductions in serum CK and cardiac lipid peroxides. The effect of AG was examined on the superoxide anion radical generated by enzymatic and nonenzymatic methods. The results indicate that AG is a potent superoxide scavenger. The superoxide scavenging effect of AG may explain, at least in part, the protective effect of AG against cardiotoxicity induced by DOX. 相似文献
102.
The structural behaviour of the human heel pad has been studied extensively due to its ability to absorb shock, protect against excessive local stress, and reduce plantar pressures. However, the material properties of the tissue have not been adequately measured. These must be known in order to perform a finite element analysis of the effect of factors such as foot geometry and shoe/surface construction on heel pad function. Therefore, the purposes of this study were to (a) measure the viscoelastic behaviour of the fat pad in compression, and (b) to determine an appropriate constitutive equation to model the tissue. A series of unconfined compression tests were performed on 8 mm diameter cylinders of fat pad tissue, consisting of quasi-static, 175, 350 mm/s and stress-relaxation tests to 50% deformation. The tissue exhibited nonlinear, viscoelastic behaviour. No significant difference was found in the quasi-static behaviour between samples from different locations and orientations in the heel. The stress-relaxation tests were used to determine the time constant (τ1=0.5 s), the 175 mm/s test to determine the relaxation coefficient (g1=28), and the 350 mm/s compression test to determine the material constants (C100=C010=0.01, C200=C020=0.1 Pa) of a single-phase, hyperelastic, linear viscoelastic strain energy function (r2=0.98). 相似文献
103.
The somatic karyotypes of 10 taxa belonging toAllium subgen.Molium (Liliaceae) from the Mediterranean area have been investigated using Giemsa C-band and fluorochrome (Hoechst, Quinacrine) banding techniques. A wide range of banding patterns has been revealed. InAllium moly (2n = 14),A. oreophilum (2n = 16) andA. paradoxum (2n = 16) C-banding is restricted to a region on each side of the nucleolar organisers and the satellites show reduced fluorescence with fluorochromes. The satellites are also C-banded and with reduced fluorescence inA. triquetrum (2n = 18), but two other chromosome pairs also have telomeric bands which are not distinguished by fluorochrome treatment. InA. erdelii (2n = 16) 4 pairs of metacentric chromosomes have telomeric C-bands while 2 pairs of telocentric chromosomes have centromeric C-banding. InA. subhirsutum (2n = 14),A. neapolitanum (2n = 28),A. trifoliatum subsp.hirsutum (2n = 14) andA. trifoliatum subsp.trifoliatum (2n = 21) chromosomes with long centromeres, consisting of a centromere and nucleolar organiser are positively C-banded on each side of the constriction. InA. subhirsutum banding is confined to the pair of chromosomes with this feature, whereas inA. neapolitanum one additional chromosome pair has telomeric bands and inA. trifoliatum there are varying numbers of chromosomes with centromeric and telomeric bands, depending on the subspecies.A. zebdanense (2n = 18) shows no C-bands. The banding patterns in this subgenus are compared with those recorded for otherAllium species and with the sectional divisions in the genus. Evidence from the banding patterns for allopolyploidy inA. trifoliatum subsp.trifoliatum andA. neapolitanum is discussed. 相似文献
104.
Ankita Varshney Yunus Ansari Nida Zaidi Ejaz Ahmad Gamal Badr Parvez Alam Rizwan Hasan Khan 《Cell biochemistry and biophysics》2014,69(1):93-101
To develop an efficient method for extracting and purifying the active ingredient, arctiin, from Fructus arctii and to investigate the protective effect of arctiin against glucose-induced rat aortic endothelial cell (RAEC) injury was investigated. Using a L9 (34) orthogonal array and two-step column chromatography (with AB-8 macroporous resin) arctiin extraction was optimized using a reflux method with 70 % ethanol. The RAECs were then treated with different concentrations of arctiin (1, 10, or 100 μg/ml). The effects of arctiin on cell viability in a high glucose medium, malondialdehyde (MDA) levels, and lactate dehydrogenase were measured using commercially available assays. After extraction, the purity of arctiin reached 95.7 %. In rats, arctiin was shown to stimulate the proliferation of RAECs in a high glucose medium in a dose-dependent manner. Exposure of RAECs to high glucose resulted in a significant increase in MDA and release of lactate dehydrogenase. This was accompanied by significant increase in nitric oxide release and expression of antiendothelial nitric oxide synthase. This technique resulted in relatively pure arctiin extraction. Furthermore, the results from this study suggest that arctiin could potentially function as a protector against vascular endothelial cell injury and further investigation is warranted. 相似文献
105.
Beta 3 adrenergic receptor Trp64Arg polymorphism and manifestation of coronary artery disease in Arabs 总被引:4,自引:0,他引:4
Abu-Amero KK Al-Boudari OM Mohamed GH Dzimiri N 《Human biology; an international record of research》2005,77(6):795-802
The substitution of tryptophan (Trp) by arginine (Arg) at position 64 in the beta3-adrenoceptor (beta3-AR) gene has been associated with obesity, diabetes mellitus, and coronary artery disease (CAD). We have investigated whether the Trp64Arg polymorphism is associated with the manifestation of CAD or one of its important risk factors, such as obesity, diabetes mellitus, elevated cholesterol and triglyceride levels, or hypertension in the Arab population. All participating subjects were genotyped for this polymorphism using the polymerase chain reaction followed by enzymatic digestion and sequencing. In the angiographed normal control subjects (n=495), 90.3% were homozygous Trp/Trp, 9.5% were heterozygous Trp/Arg, and 0.2% were homozygous for the Arg/Arg genotype, compared to 87%, 12.3%, and 0.7%, respectively, among angiographically confirmed CAD patients (n=981). There was no statistical difference in the distribution of genotypes or allele frequencies between the CAD and control groups. We carried out a stepwise logistic regression analysis to study the possible combined effect of the genotypes and other risk factors on CAD. All variables were retained in the model, with p values of 0.014, 0.006, 0.005, < 0.001, 0.045, 0.002, < 0.001, and 0.016 for genotype, diabetes mellitus, sex, family history of CAD, obesity, myocardial infarction, smoking, and age, respectively. In conclusion, the Trp64Arg polymorphism of the beta3-AR gene does not represent an independent risk factor for CAD in Arabs. However, in the presence of other CAD risk factors, this polymorphism may be used as a predictor of CAD. 相似文献
106.
Boyd M Mairs RJ Keith WN Ross SC Welsh P Akabani G Owens J Vaidyanathan G Carruthers R Dorrens J Zalutsky MR 《The journal of gene medicine》2004,6(8):937-947
BACKGROUND: Targeted radiotherapy achieves malignant cell-specific concentration of radiation dosage by tumour-affinic molecules conjugated to radioactive atoms. Combining gene therapy with targeted radiotherapy is attractive because the associated cross-fire irradiation of the latter induces biological bystander effects upon neighbouring cells overcoming low gene transfer efficiency. METHODS: We sought to maximise the tumour specificity and efficacy of noradrenaline transporter (NAT) gene transfer combined with treatment using the radiopharmaceutical meta-[(131)I]iodobenzylguanidine ([(131)I]MIBG). Cell-kill was achieved by treatment with the beta-decay particle emitter [(131)I]MIBG or the alpha-particle emitter [(211)At]MABG. We utilised our novel transfected mosaic spheroid model (TMS) to determine whether this treatment strategy could result in sterilisation of spheroids containing only a small proportion of NAT-expressing cells. RESULTS: The concentrations of [(131)I]MIBG and [(211)At]MABG required to reduce to 0.1% the survival of clonogens derived from the TMS composed of 100% of NAT gene-transfected cells were 1.5 and 0.004 MBq/ml (RSV promoter), 8.5 and 0.0075 MBq/ml (hTR promoter), and 9.0 and 0.008 MBq/ml (hTERT promoter), respectively. The concentrations of radiopharmaceutical required to reduce to 0.1% the survival of clonogens derived from 5% RSV/NAT and 5% hTERT/NAT TMS were 14 and 23 MBq/ml, respectively, for treatment with [(131)I]MIBG and 0.018 and 0.028 MBq/ml, respectively, for treatment with [(211)At]MABG. CONCLUSIONS: These results indicate that the telomerase promoters have the capacity to drive the expression of the NAT. The potency of [(211)At]MABG is approximately three orders of magnitude greater than that of [(131)I]MIBG. Spheroids composed of only 5% of cells expressing NAT under the control of the RSV or hTERT promoter were sterilised by radiopharmaceutical treatment. This observation is indicative of bystander cell-kill. 相似文献
107.
Abdel-Halim HI Imam SA Badr FM Natarajan AT Mullenders LH Boei JJ 《Cytogenetic and genome research》2004,104(1-4):193-199
Using fluorescence in situ hybridization with human band-specific DNA probes we examined the effect of ionizing radiation on the intra-nuclear localization of the heterochromatic region 9q12-->q13 and the euchromatic region 8p11.2 of similar sized chromosomes 9 and 8 respectively in confluent (G1) primary human fibroblasts. Microscopic analysis of the interphase nuclei revealed colocalization of the homologous heterochromatic regions from chromosome 9 in a proportion of cells directly after exposure to 4 Gy X-rays. The percentage of cells with paired chromosomes 9 gradually decreased to control levels during a period of one hour. No significant changes in localization were observed for chromosome 8. Using 2-D image analysis, radial and inter-homologue distances were measured for both chromosome bands. In unexposed cells, a random distribution of the chromosomes over the interphase nucleus was found. Directly after irradiation, the average inter-homologue distance decreased for chromosome 9 without alterations in radial distribution. The percentage of cells with inter-homologue distance <3 micro m increased from 11% in control cells to 25% in irradiated cells. In contrast, irradiation did not result in significant changes in the inter-homologue distance for chromosome 8. Colocalization of the heterochromatic regions of homologous chromosomes 9 was not observed in cells irradiated on ice. This observation, together with the time dependency of the colocalization, suggests an underlying active cellular process. The biological relevance of the observed homologous pairing remains unclear. It might be related to a homology dependent repair process of ionizing radiation induced DNA damage that is specific for heterochromatin. However, also other more general cellular responses to radiation-induced stress or change in chromatin organization might be responsible for the observed pairing of heterochromatic regions. 相似文献
108.
El-Shazly A Dorai G Wink M 《Zeitschrift für Naturforschung. C, Journal of biosciences》2002,57(7-8):620-623
Tanacetum santolinoides, Essential Oil Composition, n-Hexane-Ether Extract Composition The essential oil of the aerial parts of Tanacetum santolinoides was analyzed by capillary GLC and GLC-MS. Altogether 30 components were identified. The main constituents were thymol (18%), trans-thujone (17.5%), trans-chrysanthenyl acetate (13.2%), cis-chrysanthenyl acetate (9.2%), umbellulone (9.7%) and 1,8-cineole (4.7%). Similar essential oil pattern in addition to palmitic acid methyl ester, palmitic acid, stigmasterol, sitosterol and two flavonoidal aglycons were found in the n-hexane-ether extract. The oil showed strong in vitro activity against E. coli, Bacillus subtilis and Candida albicans. 相似文献
109.
Noha M. Gamil Mai A. Abd El Fattah Maha A. E. Ahmed Yousreya A. Maklad Amina A. Gamal el Din Nihad I. Eid 《Journal of biochemical and molecular toxicology》2020,34(4)
Dapagliflozin (DAPA) is used for treating type 2 diabetes, whereas lansoprazole (LPZ) is used as a traditional antiulcer drug. The present study investigated the possible antidiabetic effects of LPZ on fortified diet‐fed streptozotocin (FDF/STZ)‐induced insulin‐resistant diabetic rats. On the basis of the current results, it can be concluded that LPZ could be used as an add‐on drug along with the conventional treatment for T2D as it showed beneficial effects in the current experimental model of insulin resistance. 相似文献
110.
Roberto Bruni Angela Costantino Elena Tritarelli Cinzia Marcantonio Massimo Ciccozzi Maria Rapicetta Gamal El Sawaf Alessandro Giuliani Anna Rita Ciccaglione 《BMC structural biology》2009,9(1):48