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161.
Lineage-specific expression of c-fos and c-fms in human hematopoietic cells: Discrepancies with the in vitro differentiation of leukemia cells 总被引:2,自引:0,他引:2
Hans Kreipe Heinz J. Radzun Klaus Heidorn Mohammad Reza Parwaresch Bernard Verrier Rolf Müller 《Differentiation; research in biological diversity》1986,33(1):56-60
In vitro differentiation studies using the bipotential human leukemia cell line, HL60, have indicated that high levels of expression of two proto-oncogenes, c-fos and c-fms, are restricted to the myelomonocytic lineage. No such expression has been detected in induced granulocytic cells. In striking contrast to these observations, we found that c-fos mRNA levels are very high in purified human granulocytes, but barely detectable in blood monocytes and tissue macrophages. Human granulocytes contain, however, relatively low levels of c-fos protein, indicating that c-fos mRNA is inefficiently translated or that the protein is rapidly degraded in these cells. In closer agreement with the in vitro results, the level of the expression of c-fms is high in purified blood monocytes and undetectable in granulocytes. We found, however, that the evolution of monocytes into tissue macrophages is accompanied by a significant decrease in c-fms expression, suggesting that the function of c-fms is restricted to specific stages of monocytic differentiation. Our observations also show that results obtained using in vitro differentiation systems have to be regarded with caution, since they may not reflect the in vivo situation. 相似文献
162.
Tayyebeh Keshavarz Masoud Shams‐Bakhsh Keramat Izadpanah Mohammad A. Malboobi 《Journal of Phytopathology》2014,162(7-8):523-526
In 2011 and 2012, several cucurbit‐growing regions of Iran were surveyed and samples with symptoms similar to those induced by Cucurbit chlorotic yellows virus (CCYV) were collected. The pathogen was transmitted to cucumber and melon under greenhouse conditions by whiteflies (Bemisia tabaci). RT‐PCR using designed CCYV‐specific primer pair (CCYV‐F/CCYV‐R) resulted in amplification of the predicted size DNA fragment (870 bp) for the coat protein (CP) gene in samples collected from Boushehr, Eyvanakay and Varamin. Nucleotide sequences of the CP of the three Iranian CCYV isolates were compared with five CCYV isolates obtained from GenBank and analysed. Phylogenetically, all CCYV isolates clustered in two groups; Group I is composed of five non‐Iranian isolates from China, Lebanon, Japan, Sudan and Taiwan, and the three Iranian isolates formed Group 2. Among Iranian isolates, the Eyvanakay isolate clustered in a distinct clade with the Boushehr and Varamin isolates. A phylogenetic tree based on amino acid identity of CP showed that CCYV was closely related to Lettuce chlorosis virus (LCV), Bean yellow disorder virus (BnYDV) and Cucurbit yellow stunting disorder virus (CYSDV). This is the first report of CCYV in Iran. 相似文献
163.
rafiei Ali Khodabakhsh Farnaz Cohan Reza Ahangari Azadegan-Dehkordi Fatemeh Salimian Morteza 《Molecular biology reports》2022,49(5):3389-3399
Molecular Biology Reports - Aberrant expression of long non-coding RNAs (lncRNAs) can contribute to the pathogenesis of coronary artery disease (CAD). In this study, we aimed to evaluate the... 相似文献
164.
165.
Lin Yu-Jia Roa-Ureta Ruben H. Basali Abdullajid Usama Alcaria Joselito Francis Albaran Lindo Reynaldo Qurban Mohammad A. Prihartato Perdana K. Qasem Ali Rabaoui Lotfi 《Coral reefs (Online)》2021,40(6):1741-1756
Coral Reefs - The Arabian Gulf is a natural laboratory to examine how subtropical coral reef ecosystems might change in responding to recurring heating events because of uniquely high water... 相似文献
166.
Nazim Uddin Emon Md Munsur Alam Md Solaman Uddin Sawon Ezazul Hoque Rana Marufa Afroj Mohammad Mehedi Hasan Tanvir 《Biochemistry and Biophysics Reports》2021
Caesalpinia digyna (Rottl.) (Family: Fabaceae) is an essential medicinal plant for it's conventional uses against a kind of human disorders. This research aims to investigate the antidiarrheal, antibacterial and antifungal properties of the methanol extract of the stems extracts of the C. digyna (MECD). The in vivo antidiarrheal activity of the stem extracts were evaluated by using castor oil-induced diarrhea, castor oil-induced enteropooling and charcoal induced intestinal transit in mice model. Besides, in vitro antimicrobial potentiality of MECD was investigated by the disc diffusion method. In silico activity of the isolated compounds were performed by Schrödinger-Maestro (Version 11.1) software. In addition, The ADME/T analysis and PASS prediction were implemented by using pass online tools. In the antidiarrheal investigation, the MECD exhibited a notable inhibition rate in all test approaches which were statistically significant (p < 0.05, p < 0.1, p < 0.01). MECD 400 mg/kg showed the maximum antidiarrheal potency in all the test methods. In vitro antimicrobial analysis unveiled that, MECD revealed higher potentiality against almost all pathogens and indicates dose-dependent activity against almost all the bacteria and fungi. In the case of in silico evaluation of anti-diarrheal, anti-bacterial and anti-fungal activity, all three isolated compounds met the pre-conditions of Lipinski's five rules for drug discovery. Pass predicted study also employed for all compounds. However, The chemical constituents of the C. digyna can be a potent source of anti-diarrheal, anti-bacterial and anti-fungal medicine and further modification and simulation studies are required to establish the effectiveness of bioactive compounds. 相似文献
167.
168.
Uddin G Rauf A Arfan M Waliullah khan I Ali M Taimur M ur-Rehman I Samiullah 《Journal of enzyme inhibition and medicinal chemistry》2012,27(5):646-648
The present study was designed to investigate the whole plant of Pistacia integerrima Stewart in order to examine the pharmacological basis of the use of the plant in folk medicine for the treatment of infectious diseases and disorder. Phytochemical and pharmacological studies led to the isolation of a new triterpene pistagremic acid (3-methyl-7-(4,4,10,13,14-pentamethyl-3-2,3,4,5,6,7,10,11,12,13,14,15,16,17-tetradecahydro-1H-cyclopenta[a]phenanthren-17-yl)-oct-3-enoic). Pistagremic acid showed significant leishmanicidal activity (IC(50): 6.71 ± 0.09 μM) against Leishmania major (DESTO) promastigotes in comparison to standard compound amphotericin B (IC(50): 0.21 ± 0.06 μM). 相似文献
169.
To exploit the B-lymphocyte antigen-CD20 binding capacity of the Ibritumomab tiuxetan (IBTN) monoclonal antibody (mAb) for imaging, the over-expression of B cells in non-Hodgkin's lymphoma (NHL) (a myeloproliferative disorder of the lymphatic system) was investigated. In the current investigation, we present the labeling of the IBTN with technetium-99m ((99m)Tc) through [(99m)Tc(CO)(3)](+) precursor for radioimmunoimaging (RII) of the tumor prior to its treatment with (90)Y labeled IBTN. Labeled IBTN was radiobiologically characterized in terms of radiochemical purity, in vitro stability in human plasma, immunoreactivity, binding with Raji and Ramos cells and biodistribution in a female nude mouse (FNM) model. It was observed that the reduced IBTN (rIBTN) showed more promising radiobiologic characteristics than the nonreduced IBTN. Significantly higher transchelation was seen in excess cysteine compared with histidine. The radioconjugate showed higher saturated binding affinity with CD20 antigen. Significantly higher target (tumor) to background ratios were observed 1 h post-injection (p.i.). Based on radiochemical purity, in vitro stability, immunoreactivity, binding and biodistrubtion in the FNM model, we recommend the radiolabeling of the rIBTN using tricarbonyl technique as a potential RII agent. 相似文献
170.
Kindlin Is Mechanosensitive: Force-Induced Conformational Switch Mediates Cross-Talk among Integrins
Zeinab Jahed Zainab Haydari Akshay Rathish Mohammad R.K. Mofrad 《Biophysical journal》2019,116(6):1011-1024
Mechanical stresses directly regulate the function of several proteins of the integrin-mediated focal adhesion complex as they experience intra- and extracellular forces. Kindlin is a largely overlooked member of the focal adhesion complex whose roles in cellular mechanotransduction are only recently being identified. Recent crystallographic experiments have revealed that kindlins can form dimers that bind simultaneously to two integrins, providing a mechanistic explanation of how kindlins may promote integrin activation and clustering. In this study, using the newly identified molecular structure, we modeled the response of the kindlin2 dimer in complex with integrin β1 to mechanical cytoskeletal forces on integrins. Using molecular dynamics simulations, we show that forces on integrins are directly transmitted to the kindlin2 dimerization site, resulting in a shift in an R577-S550/E553 interaction network at this site. Under force, R577 on one protomer switches from interacting with S550 to forming new hydrogen bonds with E553 on the neighboring protomer, resulting in the strengthening of the kindlin2 dimer in complex with integrin β1. This force-induced strengthening is similar to the catch-bond mechanisms that have previously been observed in other adhesion molecules. Based on our results, we propose that the kindlin2 dimer is mechanosensitive and can strengthen integrin-mediated focal adhesions under force by shifting the interactions at its dimerization sites. 相似文献