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131.
The effects of disodium ethane-1-hydroxy-1,1-diphosphonate (EHDP) on the in vitro functions of guinea pig macrophages were studied. A high dose (1 mg/ml) of EHDP inhibited interleukin 1 (IL 1) production by oil-induced peritoneal macrophages stimulated with muramyl dipeptide (MDP), lipopolysaccharide (LPS), phorbol myristic acetate (PMA), heat-aggregated IgG2 or calcium ionophore A23187. On the other hand, low doses (less than 0.125 mg/ml) of EHDP augmented the MDP induced IL 1 production by macrophages. This biphasic effect was also observed when macrophages were exposed to EHDP at 37 C for 24 hr and then stimulated with IL 1 inducers. Superoxide anion generation induced by formyl peptide or PMA was not affected by preincubation of the macrophages with doses of EHDP up to 1 mg/ml. Adherence and spreading of macrophages was inhibited by EHDP in a dose dependent manner without affecting cell viability. These results demonstrated that EHDP acted on macrophages directly and modulated IL 1 production in vitro. 相似文献
132.
Francisco J Gálvez-Gastélum Aida A Segura-Flores María D Senties-Gomez Jose F Muñoz-Valle Juan S Armendáriz-Borunda 《Journal of biomedical science》2010,17(1):42
Background
Liver fibrosis ranks as the second cause of death in México's productive-age population. This pathology is characterized by acummulation of fibrillar proteins in hepatic parenchyma causing synthetic and metabolic disfunction. Remotion of excessive fibrous proteins might result in benefit for subjects increasing survival index. The goal of this work was to find whether the already known therapeutical effect of human urokinase Plasminogen Activator and human Matrix Metalloprotease 8 extends survival index in cirrhotic animals. 相似文献133.
The nucleotide sequence data reported in this paper have been submitted to the GenBank nucleotide sequence database and have been assigned the accession numbers D37952, D37953, and D37954 相似文献
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136.
Ensieh Sajadi Sara Dadras Mohammad Bayat Shabnam Abdi Hamid Nazarian Sanaz Ziaeipour Fatemeh Mazini Mahsa Kazemi Mohammad Bagheri Aida Valizadeh Mohammad-Amin Abdollahifar 《Journal of cellular biochemistry》2019,120(10):17312-17325
The current study was conducted to assess the relationship between testicular cells in spermatogenesis, through which the production of healthy and mature sperm is essential. However, it seems necessary to obtain more information about the three-dimensional pattern of the testis cells arrangement, which is directly related to the function of the testis after induction of diabetes. Twelve adult mice (28-30 g) were assigned into two experimental groups: (1) control and (2) diabetic (40 mg/kg STZ). The epididymal sperm collected from the tail of the epididymis and testes samples were taken for stereology, immunocytochemistry and RNA extraction. Our data showed that diabetes could notably decrease the number of testicular cells, together with a reduction of total sperm count. In addition, the results from the second-order stereology indicated the significant changes in the spatial arrangement of Sertoli cells and spermatogonial cells in the diabetic groups, in comparison with the control (P < .05). Moreover, the immunohistochemistry results showed a significant reduction in Sex-determining Region Y (SRY) box 9 gene (SOX9), vimentin, occludin, and connexin-43 positive cells in the diabetic groups compared with the control (P < .05). Furthermore, our data showed that the expression of steroidogenic acute regulatory protein steroidogenic acute regulatory protein (StAR) and peripheral benzodiazepine receptor peripheral benzodiazepine receptor (PBR) was significantly reduced in the diabetic groups, in comparison with the control (P < .05). These findings suggest that structural and functional changes of testis cells after induction of diabetes cause the alterations in the spatial arrangement of Sertoli and spermatogonial cells, ultimately influencing the normal spermatogenesis in mice. 相似文献
137.
Protein kinase C located in rat liver nuclei. Partial purification and biochemical and immunochemical characterization 总被引:7,自引:0,他引:7
A Masmoudi G Labourdette M Mersel F L Huang K P Huang G Vincendon A N Malviya 《The Journal of biological chemistry》1989,264(2):1172-1179
In the rat liver homogenate, maximal protein kinase C activity was found at two calcium concentrations (1.75 and 3.5 mM). Subcellular fractionation of the liver homogenate revealed that the protein kinase C activity requiring 1.75 mM calcium was present only in the cytosolic and particulate subcellular fractions. The protein kinase C activity requiring 3.5 mM calcium concentration was mainly located in the rat liver nuclei preparation. About 19% of the liver homogenate protein kinase C activity requiring 3.5 mM calcium was present in the nuclei. Goat anti-rat brain protein kinase C antibodies revealed a single immunoreactive band at 80-82 kDa in the rat liver nuclear, particulate, or cytosolic fractions. Based on the ratio of plasma membrane marker enzyme activity determined in the nuclear preparation, the purity of the isolated nuclei was ascertained. Rat liver nuclear protein kinase C activity has been partially purified. The purification steps sequentially employed were Triton X-100 extraction of isolated nuclei, DEAE-cellulose chromatography, Phenyl-Superose, and Mono Q (fast protein liquid) chromatography. The final purification step revealed, by silver nitrate staining on sodium dodecyl sulfate-polyacrylamide gel electrophoresis, two protein bands at 80 and 66 kDa, respectively. These findings provide definitive data regarding the nuclear location of protein kinase C. The nuclear location of protein kinase C may lead to an understanding of the molecular pathway involved in signal transduction from the plasma membrane to the nucleus. 相似文献
138.
Hesham Saeed Hadeer Soudan Amany El-Sharkawy Aida Farag Amira Embaby Farid Ataya 《The protein journal》2018,37(5):461-471
Recombinant l.asparaginase, L.ASNase, from Pseudomonas aeruginosa was purified using nickel affinity chromatography. The affinity purified L.ASNase exhibited a protein band with a molecular weight of 72.4 kDa on a native polyacrylamide gel and 36.276 kDa using SDS–PAGE. The activity of the purified L.ASNase was enhanced by Mg2+ and inhibited by Zn2+ at a concentration of 5 mM. The specificity of the recombinant L.ASNase towards different substrates was examined, and it was found that the enzyme showed the highest activity towards l.asparagine. Moreover, the enzyme showed lower activity towards other substrates such as L.glutamine, urea and acrylamide. The in vitro hemolysis assay revealed that the purified L.ASNase did not show hemolysis effect on blood erythrocytes. Serum and trypsin half-life of L.ASNase suggested that the recombinant L.ASNase retained 50% of its initial activity after 90 and 60 min incubation period in serum and trypsin separately. 相似文献
139.
Sekena H Abdel-Aziem Heba A.M. Abd El-Kader Faten M. Ibrahim Hafiza A Sharaf Aida I. El makawy 《Journal of Genetic Engineering and Biotechnology》2018,16(2):653-660
Microalgae provide a wealthy natural resource of bioactive compounds, which have many biological activities. Monosodium glutamate is a food additive that acts either as food preservatives or as tastiness enhancer. It was confirmed that monosodium glutamate poses a serious responsibility in the pathogenesis of anovulatory infertility. Therefore, the idea of this research was directed to reveal efficiency of Chlorella vulgaris and Spirulina platensis extracts against the ovarian dysfunction resulted due to monosodium glutamate consumption. Adult female albino mice were gavages orally monosodium glutamate alone or with either Chlorella vulgaris or Spirulina platensis aqueous extracts for 28?days. Female mice were subjected to superovulation to study the oocytes nuclear maturation stages. Histological and quantitative investigation was carried on ovaries. Biochemical assessment to measure the sex hormones level and ovarian enzymatic antioxidants was done. In addition, ovarian antioxidant mRNA genes were determined using quantitative PCR and Glyceraldehyde-3-phosphate dehydrogenase was used as an internal control. The result revealed that monosodium glutamate reduced the oocytes quality and maturation rate, while, both algae improve the oocyte quality and maturation rate than in monosodium glutamate group. Chlorella vulgaris and Spirulina platensis improved the monosodium glutamate ovarian tissue histological alteration, sex hormones content and raised the ovarian enzymatic antioxidants level. In addition, monosodium glutamate markedly diminished the Glutathione peroxidase, superoxide dismutase and catalase mRNA expressions, However, Chlorella vulgaris or Spirulina platensis upregulated the expression of genes close to control. In conclusion, Chlorella vulgaris and Spirulina platensis showed potential alleviative role against the monosodium glutamate ovarian dysfunction. 相似文献
140.
Jose L. Horreo America G. Valiente Alba Ardura Aida Blanco Claudia Garcia‐Gonzalez Eva Garcia‐Vazquez 《Ecology and evolution》2018,8(1):521-529
Biological changes occurring as a consequence of domestication and/or captivity are not still deeply known. In Atlantic salmon (Salmo salar), endangered (Southern Europe) populations are enhanced by supportive breeding, which involves only 6 months of captive rearing following artificial spawning of wild‐collected adults. In this work, we assess whether several fitness‐correlated life‐history traits (migratory behavior, straying rate, age at maturity, and growth) are affected by early exposure to the captive environment within a generation, before reproduction thus before genetic selection. Results showed significant differences in growth and migratory behavior (including straying), associated with this very short period of captivity in natural fish populations, changing even genetic variability (decreased in hatchery‐reared adults) and the native population structure within and between rivers of the species. These changes appeared within a single generation, suggesting very short time of captivity is enough for initiating changes normally attributed to domestication. These results may have potential implications for the long‐term population stability/viability of species subjected to restoration and enhancement processes and could be also considered for the management of zoo populations. 相似文献