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91.
Ayatollahi M Salmani MK Geramizadeh B Tabei SZ Soleimani M Sanati MH 《World journal of stem cells》2012,4(1):1-8
AIM: To improve the isolation and expansion of human marrow-derived mesenchymal stem cells (MSCs) based on rat samples. METHODS: Based on the fact that rat MSCs are relatively easy to obtain from a small aspirate, bone marrow-derived MSCs from rat were cultured and characterized to set up the different protocols used in this study. Then, accordingly, almost the same protocols were performed on human healthy bone marrow samples, after obtaining approval of the ethics committee and gaining informed consent. We used different protocols and culture conditions, including the type of basal media and the culture composition. The MSCs were characterized by immunophenotyping and differentiation. RESULTS: There was no difference in morphology and proliferation capacity between different culture media at the first passage. During the 5-7th passages, the cells gradually lost their morphology and proliferation potential on Dulbecco’s modified Eagle’s medium (DMEM) high glucose and α modified Eagle’s medium. Although the cells expanded rapidly for up to 10 passages on DMEM low glucose containing 10% to 15% fetal calf serum (FCS), their proliferation was arrested without change in morphology and differentiation capacity at the third passage on 5% FCS. Flow cytometric analysis and functional tests confirmed that more than 90% of marrow cells which were isolated and expanded by our selective protocols were MSCs. CONCLUSION: We improved the isolation and expansion of human bone marrow derived MSCs, based on rat sample experiments, for further experimental and clinical use. 相似文献
92.
93.
Sternlicht MD Sunnarborg SW Kouros-Mehr H Yu Y Lee DC Werb Z 《Development (Cambridge, England)》2005,132(17):3923-3933
Epithelial-mesenchymal crosstalk is essential for tissue morphogenesis, but incompletely understood. Postnatal mammary gland development requires epidermal growth factor receptor (EGFR) and its ligand amphiregulin (AREG), which generally must be cleaved from its transmembrane form in order to function. As the transmembrane metalloproteinase ADAM17 can process AREG in culture and Adam17(-/-) mice tend to phenocopy Egfr(-/-) mice, we examined the role of each of these molecules in mammary development. Tissue recombination and transplantation studies revealed that EGFR phosphorylation and ductal development occur only when ADAM17 and AREG are expressed on mammary epithelial cells, whereas EGFR is required stromally, and that local AREG administration can rescue Adam17(-/-) transplants. Several EGFR agonists also stimulated Adam17(-/-) mammary organoid growth in culture, but only AREG was expressed abundantly in the developing ductal system in vivo. Thus, ADAM17 plays a crucial role in mammary morphogenesis by releasing AREG from mammary epithelial cells, thereby eliciting paracrine activation of stromal EGFR and reciprocal responses that regulate mammary epithelial development. 相似文献
94.
Zakharov A Giersberg M Hosein F Melzer M Müntz K Saalbach I 《Journal of experimental botany》2004,55(402):1463-1471
The organ specificity of four promoters that are known to direct seed-specific gene expression was tested. Whereas the phaseolin (phas)- and legumin B4 (leB4)-promoters were from genes encoding 7S and 11S globulins from Phaseolus vulgaris and Vicia faba, respectively, the usp- and the sbp-promoters were from non-storage protein genes of V. faba. The expression of different promoter-reporter gene fusions was followed either by RT-PCR or by registering the reporter enzyme activity in organs of transgenic tobacco, pea, narbon bean, or linseed. In addition to seeds, the promoters directed reporter gene expression in pollen and in seed coats. USP-, vicilin- and legumin-mRNA were detected by RT-PCR in pollen of Pisum sativum and V. faba. Expression during microsporogenesis and embryogenesis seems to be a general character of various seed protein genes. 相似文献
95.
Sadaf Rezvanpoor Neda Shakour Nazli Ahangarzadeh Hamid Bakherad Saghi Sepehri Ghazaleh Farhadi Mohammad Hosein Pakdel Mehrdad Iranshahi 《化学与生物多样性》2023,20(5):e202300054
New series of triazole-tetrahydropyrimidinone(thione) hybrids ( 9a – g ) were synthesized. FT-IR, 1H-NMR, 13C-NMR, elemental analysis and mass spectroscopic studies characterized the structures of the synthesized compounds. Then, the synthesized compounds were screened to determine the urease inhibitory activity. Methyl 4-(4-((1-(2-chlorobenzyl)-1H-1,2,3-triazol-4-yl)methoxy)phenyl)-6-methyl-2-thioxo-1,2,3,4-tetrahydropyrimidine-5-carboxylate ( 9c ) exhibited the highest urease inhibitory activity (IC50=25.02 μM) among the compounds which was almost similar to thiourea as standard (IC50=22.32 μM). The docking study of the screened compounds demonstrated that these compounds fit well in the urease active site. Based on the docking study, compound 9c with the highest urease inhibitory activity showed chelates with both Ni2+ ions of the urease active site. Moreover, the molecular dynamic study of the most potent compounds showed that they created important interactions with the active site flap residues, His322, Cys321, and Met317. 相似文献
96.
Alieh Ameri Ghadamali Khodarahmi Hamid Forootanfar Farshid Hassanzadeh Gholam‐Hosein Hakimelahi 《化学与生物多样性》2018,15(3)
A series of hybrid aldimine‐type Schiff base derivatives including trimethoxyphenyl ring and 1,2,4‐triazole‐3‐thiol/thione were designed as tubulin inhibitors. The molecular docking simulations on tubulin complex (PDB: 1SA0) revealed that derivatives with nitro and/or chloro or dimethylamino substitutes (4‐nitro, 2‐nitro, 3‐nitro, 4‐Cl‐3‐nitro, and 4‐Me2N) on the aldehyde ring were the best compounds with remarkable binding energies (?9.09, ?9.07, ?8.63, ?8.11, and ?8.07 kcal mol?1, respectively) compared to colchicine (?8.12 kcal mol?1). These compounds were also showed remarkable binding energies from ?10.66 to ?9.79 and ?10.12 to ?8.95 kcal mol?1 on human (PDB: 1PD8) and Candida albicans (PDB: 3QLS) DHFR, respectively. The obtained results of cytotoxic activities against HT1080, HepG2, HT29, MCF‐7, and A549 cancer cell lines indicated that 4‐nitro and 2‐nitro substituted compounds were the most effective agents by mean IC50 values of 11.84 ± 1.01 and 19.92 ± 1.36 μm , respectively. 4‐Nitro substituted compound (5 μm ) and 2‐nitro substituted compound (30 μm ) were able to strongly inhibit the tubulin polymerization compared to colchicine (5 μm ) and 4‐nitro substituted compound displayed IC50 values of 0.16 ± 0.01 μm compared to that of colchicine (0.19 ± 0.01 μm ). This compound also showed the lowest MIC values on all tested microbial strains including three Gram‐positive, four Gram‐negative, and three yeast pathogens. 相似文献
97.
Arrhenius plots were generated on the activity of rat liver mitochondrial cytochrome c oxidase from Metrecal-sucrose fed controls and Metrecal-alcohol fed experimentals. Chronic alcohol feeding resulted in diminished specific activity of cytochrome c oxidase and abolition of the discontinuity temperature at 17.5 degrees C found in the controls. Twenty-four hours after alcohol withdrawal, a discontinuity temperature reappeared at 14.4 degrees C; at 48 h it increased to 22.6 degrees C and returned to normal (17.4 degrees C) at 72 h. Such liver mitochondria also showed a decreased capacity to oxidize the acetyl group of acetyl carnitine immediately following prolonged alcohol feeding. When the assay was performed following withdrawal from alcohol 24 h later, oxidation was enhanced and this effect persisted for another 48 h. These latter results revealed a diminished capacity of such mitochondria to oxidize short chain fatty acids during alcohol feeding and the reverse during alcohol withdrawal. These results, complemented by thermographic data obtained through differential scanning calorimetry (DSC) reinforced the view that chronic alcoholic feeding induced adaptive changes in the fluidity of rat liver mitochondrial membrane lipids. Moreover, they demonstrated that in the microenvironment of the membrane-bound enzymes on withdrawal from ethanol, the membrane readapts to the new conditions without alcohol. This involved modulation of membrane structure and function and at the same time demonstrated a role for the membrane in the expression of tolerance and functional dependence on alcohol. 相似文献
98.
Morphological analysis of Brandt's hedgehog (Paraechinus hypomelas) reflects the isolation history of Persian Gulf islands and has implications for taxonomy
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99.
Targeted gene disruption was used to investigate the function of MYO1, an unconventional myosin gene in Tetrahymena thermophila. Phenotypic analysis of a transformed strain that lacked a functional MYO1 gene was conducted at both 20 degrees C and 35 degrees C. At either temperature the delta MYO1 strain had a smaller cytoplasm/nucleus ratio than wild type. At 20 degrees C, delta MYO1 populations had a longer doubling time than wild type, lower saturation density, and a reduced rate of food vacuole formation. However, at 35 degrees C, these characteristics were comparable to wild type. Although micronuclear division and cytokinesis appeared normal in delta MYO1 cells, failure of the macronucleus to elongate properly resulted in unequal segregation of macronuclear DNA in cells maintained at either 20 degrees C or 35 degrees C. 相似文献
100.
Afsharimani B Moezi L Sadeghipour H Rahimzadeh-Rofouyi B Nobakht M Sanatkar M Ghahremani MH Dehpour AR 《Canadian journal of physiology and pharmacology》2007,85(10):1038-1046
The mechanism of action of lithium, an effective treatment for bipolar disease, is still unknown. In this study, the mesenteric vascular beds of control rats and rats that were chronically treated with lithium were prepared by the McGregor method, and the mesenteric vascular bed vasorelaxation responses were examined. NADPH-diaphorase histochemistry was used to determine the activity of NOS (nitric oxide synthase) in mesenteric vascular beds. We demonstrated that ACh-induced vasorelaxation increased in the mesenteric vascular bed of rats treated with lithium. Acute No-nitro-L-arginine methyl ester (L-NAME) administration in the medium blocked ACh-induced vasorelaxation in the control group more effectively than in lithium-treated rats, while the vasorelaxant response to sodium nitroprusside, a NO donor, was not different between lithium-treated and control groups. Acute aminoguanidine administration blocked ACh-induced vasorelaxation of lithium-treated rats, but had no effect in the control rats. Furthermore, NOS activity, determined by NADPH-diaphorase staining, was significantly greater in the mesenteric vascular beds from chronic lithium-treated rats than in those from control rats. These data suggest that the enhanced ACh-induced endothelium-derived vasorelaxation in rat mesenteric bed from chronic lithium-treated rats might be associated with increased NOS activity, likely via iNOS. Simultaneous acute L-NAME and indomethacin administration suggests the possible upregulation of EDHF (endothelium-derived hyperpolarizing factor) in lithium-treated rats. 相似文献