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401.
Forster AH Wang MM Butler WF Chachisvilis M Chung TD Esener SC Hall JM Kibar O Lykstad K Marchand PJ Mercer EM Pestana LM Sur S Tu E Yang R Zhang H Kariv I 《Analytical biochemistry》2004,327(1):14-22
To facilitate quantitation of cellular apoptotic responses to various antineoplastic agents, a laser-based technology, Optophoresis, has been developed to provide analysis of cells without any need for labeling or cell processing. Optophoresis is defined as the analysis of the motion of cells, where the motion is either induced or modified by a moving optical gradient field, which produces radiation pressure forces on the cells in an aqueous suspension. Quantitation of the induced motion provides a basis for distinguishing one population of cells from another. One Optophoretic technique, Fast Scan, measures the distribution of distances traversed by a population of cells when exposed to a fast-moving optical gradient. Fast Scan was validated using a cell-based model of chronic myeloid leukemia treated with Gleevec, a specific inhibitor of aberrant Bcr-Abl protein kinase. The Optophoretic measurements were quantitatively comparable to reference assays with regard to drug selectivity and potency and to target specificity, demonstrating the suitability of this technology for pharmaceutical and clinical applications. 相似文献
402.
Mohamed M. El-Seweidy Nermin A.H. Sadik Olfat G. Shaker 《Archives of biochemistry and biophysics》2011,(1):48
This study examined the downstream signaling whereby hyperglycemia may lead to myocardial fibrosis and apoptosis in the left ventricle of diabetic rats. The effects of sulfurous mineral water or sodium hydrosulfide (NaHS) as possible modulators were also examined. Sulfurous mineral water (as drinking water) and NaHS (14 μmol/kg/day, IP) were administered for 7 week to rats with streptozotocin (STZ)-induced diabetes. Hyperglycemia, overproduction of glycated hemoglobin (HbA1C) and serum decline in insulin, C-peptide and insulin like growth factor-I (IGF-I) were observed in diabetic rats. Up-regulation of gene expressions of nuclear factor (NF-κB), profibrogenic growth factor such as transforming growth factor-β1 (TGF-β1), matrix metalloproteniase-2 (MMP-2), procollagen-1 and Fas ligand (Fas-L) were observed in the left ventricle of diabetic rats. A linear positive correlation between TGF-β1 and MMP-2 was also detected in diabetic group. An increase in hydroxyproline level and a disturbance in oxidative balance were detected in heart of diabetic rats. Sulfurous mineral water and NaHS treatment possibly, by improving cardiac GSH level, counteracted the enhanced expression of NF-κB, the profibrogenic and apoptotic parameters. Histopathological examination was in accordance with the biochemical and molecular findings of this study. We suggest a novel therapeutic approach of sulfurous mineral water and exogenous supplementation of H2S in diabetic cardiomyopathy. 相似文献
403.
Aghanouri R Ghanei M Aslani J Keivani-Amine H Rastegar F Karkhane A 《American journal of physiology. Lung cellular and molecular physiology》2004,287(6):L1160-L1164
Over 100,000 Iranian war veterans suffer from chronic effects of mustard gas exposure. Sulfur mustard was used by Iraq during the Iraqi-imposed war on Iran (between 1980 and 1988). The major complaints of these patients are mild interstitial fibrosis and bronchiolitis. We aimed to determine the state of fibrosis progression and assessed transforming growth factor (TGF)-beta1 levels in pulmonary samples and in bronchoalveolar lavage (BAL) aspirates. A total of 126 war veterans confirmed for lung disease were assessed and compared with three control groups: 1) 64 veterans not exposed to chemical agents, 2) 12 idiopathic pulmonary fibrosis civilian patients, and 3) 33 normal persons. BAL was performed via a flexible fiber-optic bronchoscope and the standard manual method. Total protein was measured by Bradford assay, and samples were corrected with regard to coefficients. Samples were concentrated 15-fold by lyophilization and resolubilization. Samples were double-checked using an ELISA test kit. The Mann-Whitney test was used for the data analysis using commercial software. We detected that significant differences between TGF-beta1 levels between the case group and control group 1 (P = 0.001) and control group 3 (P = 0.003). No significant differences were found between the case group and control group 2 (P = 0.57). Inflammation and fibrotic processes in lung tissue of patients exposed to sulfur mustard may be progressive so IFN-gamma may be a useful drug to these patients' treatment. 相似文献
404.
Sidki Sadik 《American journal of botany》1962,49(3):290-297
Sadik , Sidki . (U. California, Davis.) Morphology of the curd of cauliflower. Amer. Jour. Bot. 49(3): 290–297. Illus. 1962.—The development of the curd and inflorescence of cauliflower, Brassica oleracea Linn., var. botrytis D.C., is described. The cultivars ‘Snowball M’ and ‘February-Early-March’ were studied. The curd has a nonfasciated and monopodial type of branching. Curd initiation of ‘Snowball M’ is not dependent on vernalization, but the curd of ‘February-Early-March’ and the floral primordia of both cultivars are initiated only after vernalization. Associated with flowering is the disruption of the curd by the elongation of some of the inflorescence branches. The initiation of leaves, branches, and floral primordia follows a 5 + 8 phyllotaxy throughout all stages of development. This system of phyllotaxy changes at the time of initiation of floral parts. 相似文献
405.
A study was made of the modifying effect of glycerol on the survival rate and gamma radiation-induced mutagenesis of Salmonella typhimurium cells TA98, TA100 and TA102. The DMF value, with respect to the survival rate, was 2.05-0.20. The dependence of the yield of gamma radiation-induced mutants on radiation dose was described by the curve with a maximum; the mutation frequency M(D) was well described by a gradual function M(D) = kDx. DMF values of the induced mutagenesis amounted to 2 for strains TA100 and TA102, and 1.5 for strain TA98. 相似文献
406.
Muhammad Abdul Aziz Muhammad Adnan Amir Hasan Khan Atiq Ur Rehman Rahmatullah Jan Jafar Khan 《Journal of ethnobiology and ethnomedicine》2016,12(1):53
Background
Medicinal flora plays a vital role in treating various types of ailments in living beings. The present study was planned to investigate and document systematically the indigenous knowledge in a scientifically little explored area of Ladha sub-division, South Waziristan agency, Pakistan. Hence, this study would contribute positively to the field of ethnopharmacology.Methods
Prior to ethnomedicinal data collection, regular field visits were conducted during the month of May and June 2015 to locate the sites and respondents from where the traditional knowledge was to be recorded. Ethno-medicinal data was collected during the month July and August 2015 through rapid appraisal approach (RAA) based on direct interaction with the indigenous communities by making group discussions, corner meetings and semi-structured interviews. Data was evaluated statistically by using the index of Use value (UV) and Frequency of citations (FC).Results
A total of 82 medicinal plants belonging to 42 families were reported in the study. Leaves were the most frequently used plant parts. Highest use values were recorded for Peganum harmala (0.93), Punica granatum (0.91), Thymus mongolicus (0.90), Chenopodium album (0.89), Coriandrum sativum (0.87), Mentha longifolia (0.87), Lactuca serriola (0.87) and Portulaca oleracea (0.87). Medicinal plants used for the gastro intestinal complexities and respiratory diseases were more than 9% followed by skin and diarrhea (7% each), liver disorders (5%) cough and cold fever (5%).Conclusion
People of the area mostly still rely on traditional herbal therapies. Keeping in mind the dependence of the indigenous community for their primary health care on such herbal remedies, pharmacological and critical toxicological investigation of certain flora is necessary. Moreover, projects should be designed to analyze the existing issues and problems related with medicinal plants conservation.407.
Fluoride has been implicated as a pathologic mediator of fluorosis. Interestingly neuronal destruction, synaptic injury occurs
by a mechanism involving oxidative stress, however, its effects in developmental stages of life, during maternal fluoride
exposure and amelioration are not elucidated. In the present study, pregnant Wistar albino rats were exposed to 50 and 150
ppm fluoride in drinking water during gestation and post gestation. After parturition the pups born to the experimental animals
were administered daily with selected antioxidants for 21 consecutive days. Fluoride administration substantially enhanced
fluoride accumulation, lipid peroxidation and decreased the activity of superoxide dismutase, catalase, glutathione peroxidase,
glutathione-S-transferase and glutathione levels in discrete regions of central nervous system. The results significantly
(P < 0.05) demonstrated the effect of fluoride through exacerbated oxidative damage and disrupted antioxidant homeostasis, leading
to altered neuronal integrity. The administration of antioxidants vitamin E, vitamin C, selenium and zinc produced a promising
accost and timely intervention to the aggravated impairment during highly vulnerable early stage of life. 相似文献
408.
Chronic fluoride intoxication results in pathophysiological complications pertaining to soft tissues, called non-skeletal fluorosis. This study examined whether fluoride-induced alterations in selected parameters that are indicative of mitochondrial dysfunction accompany the toxic effects of fluoride in discrete brain regions in vivo and also explored the possibility of treatment with Ginseng (GE) and Banaba (BLE) either alone or with their co-exposure which is capable of reversing parameters indicative of fluoride-induced impairments in mitochondrial function. Swiss mice, Mus musculus, were given 270 ppm fluoride (600 ppm NaF) in their drinking water for 30 days, while continuing the fluoride exposure, toxicated animals were given differential doses (50–250 mg/kg body wt) of phytoextracts through oral gavage for 2 weeks. Discrete brain regions separated from dissected animals to perform biochemical assessments. Disturbances in mitochondrial enzyme complexes (I-IV) and decrements in TCA enzymes (ICDH, SDH, and aconitase) were noted in discrete brain regions upon F exposure, suggesting mitochondrial dysfunction. In addition, a significant reduction in oxidative stress indices with increased MDA content as well as decrease in reduced glutathione content and increases in catalase and SOD enzyme activity suggests the involvement of severe oxidative stress affecting the mitochondrial function(s). Treatment with either GE or BLE reversed F-induced alterations in augmenting the suppressed complex enzymes followed by TCA enzymes and oxidative stress indices in a dose independent manner. However, the co-exposure of GE and BLE at a dose of 150 mg/kgbw appeared to restore mitochondrial functioning. These results provide in vivo evidence supporting the hypothesis that fluoride induces impairments in mitochondrial function, which can be reversed by treatment with GE and BLE as well their co-exposure at 150 mg/kgbw. 相似文献
409.
Jafar Seyfabadi Nabiallah Kheirabadi Fereidoon Owfi Alireza Mahvary 《Zoology in the Middle East.》2013,59(4):327-334
Shell selection behaviour and spatial distribution of three hermit crab species, Diogenes avarus, D. karwarensis, and Areopaguristes perspicax, were studied at six sites along the intertidal zones of Hormuz Island in the Persian Gulf. 1025 specimens were collected occupying altogether 31 shell species (D. avarus 28 species, A. perspicax 22 species, and D. karwarensis 8 species). Diogenes avarus was found to be by far the most abundant of these three crab species, and Cerithidea cingulata the dominant shell occupied by these hermit crabs. The distribution of the hermit crabs significantly varied (p<0.05) among the sites. The number and the wide diversity of shells occupied in different sites show that the main factor in shell selection for these hermit crabs is the abundance and distribution of shell species in the field. 相似文献
410.
Anke Walz Stefan Odenbreit Kai Stühler Andreas Wattenberg Helmut E. Meyer Jafar Mahdavi Thomas Borén Stefan Ruhl 《Proteomics》2009,9(6):1582-1592
Because gastric infection by Helicobacter pylori takes place via the oral route, possible interactions of this bacterium with human salivary proteins could occur. By using modified 1‐ and 2‐D bacterial overlay, binding of H. pylori adhesins BabA and SabA to the whole range of salivary proteins was explored. Bound salivary receptor molecules were identified by MALDI‐MS and by comparison to previously established proteome maps of whole and glandular salivas. By use of adhesin‐deficient mutants, binding of H. pylori to MUC7 and gp‐340 could be linked to the SabA and BabA adhesins, respectively, whereas binding to MUC5B was associated with both adhesins. Binding of H. pylori to the proline‐rich glycoprotein was newly detected and assigned to BabA adhesin whereas the SabA adhesin was found to mediate binding to newly detected receptor molecules, including carbonic anhydrase VI, secretory component, heavy chain of secretory IgA1, parotid secretory protein and zinc‐α2‐glycoprotein. Some of these salivary glycoproteins are known to act as scavenger molecules or are involved in innate immunity whereas others might come to modify the pathogenetic properties of this organism. In general, this 2‐D bacterial overlay technique represents a useful supplement in adhesion studies of bacteria with complex protein mixtures. 相似文献