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Morteza Djamali Matthew D. Jones Jérémy Migliore Silvia Balatti Marianela Fader Daniel Contreras Sébastien Gondet Zahra Hosseini Hamid Lahijani Abdolmajid Naderi Lyudmila S. Shumilovskikh Margareta Tengberg Lloyd Weeks 《Vegetation History and Archaeobotany》2016,25(3):255-269
Ancient Persia witnessed one of its most prosperous cultural and socio-economic periods between 550 bc and ad 651, with the successive domination of the Achaemenid, Seleucid, Parthian and Sassanian Empires. During this period agricultural activities increased on the Iranian plateau, as demonstrated by a remarkable arboricultural expansion. However, available data are not very informative about the spatial organization of agricultural practices. The possible links between climate conditions and agricultural activities during this millennium of continuous imperial domination are also unclear, due to the lack of parallel human-independent palaeoclimatic proxies. This study presents a new late Holocene pollen-based vegetation record from Lake Parishan, SW Iran. This record provides invaluable information regarding anthropogenic activities before, during and after the empires and sheds light on (i) spatial patterning in agricultural activities and (ii) possible climate impacts on agro-sylvo-pastoral practices during this period. Results of this study indicate that arboriculture was the most prominent form of agricultural activity in SW Iran especially during the Achaemenid, Seleucid and Parthian periods. Contrary to the information provided by some Greco-Roman written sources, the record from Lake Parishan shows that olive cultivation was practiced during Achaemenid and Seleucid times, when olive cultivation was significant, at least in this basin located close to the capital area of the Achaemenid Empire. In addition, pollen from aquatic vegetation suggests that the period of the latter centuries of the first millennium bc was characterized by a higher lake level, which might have favoured cultural and socio-economic prosperity. 相似文献
43.
Two-dimensional 1H NMR of three spin-labeled derivatives of bovine pancreatic trypsin inhibitor 总被引:2,自引:0,他引:2
P A Kosen R M Scheek H Naderi V J Basus S Manogaran P G Schmidt N J Oppenheimer I D Kuntz 《Biochemistry》1986,25(9):2356-2364
Three nitroxide spin-labeled monoderivatives of bovine pancreatic trypsin inhibitor were prepared with the amino-specific reagent succinimidyl 1-oxy-2,2,5,5-tetramethyl-3-pyrroline-3-carboxylate. The monoderivatives were purified by ion-exchange and affinity chromatography. Thin-layer maps of tryptic peptides of the monoderivatives showed that the spin-label was incorporated at either the alpha-amino group, Lys-15, or Lys-26. Two-dimensional J-correlated 1H NMR spectra of the monoderivatives were recorded. Spectra were also recorded after reduction by ascorbic acid of the nitroxide label to hydroxylamine. With the nitroxide label present, significant line-broadening effects on many of the cross peaks in the spectra were observed. The extent of line broadening for the C alpha H-NH cross peaks was qualitatively correlated with the distance between the labeled amino group and the average C alpha H-NH position in the crystal structure. The spin-label affects cross peaks of protons within approximately 15 A. This study suggests that it is feasible to accumulate sufficient intramolecular distances in order to determine protein solution structures with the aid of distance geometry algorithms. 相似文献
44.
Hybrid chitosan–ß‐glycerol phosphate–gelatin nano‐/micro fibrous scaffolds with suitable mechanical and biological properties for tissue engineering 下载免费PDF全文
Marzieh Lotfi Roohollah Bagherzadeh Hojjat Naderi‐Meshkin Elahe Mahdipour Asghar Mafinezhad Hamid Reza Sadeghnia Habibollah Esmaily Masoud Maleki Halimeh Hasssanzadeh Majid Ghayaour‐Mobarhan Hamid Reza Bidkhori Ahmad Reza Bahrami 《Biopolymers》2016,105(3):163-175
Scaffold‐based tissue engineering is considered as a promising approach in the regenerative medicine. Graft instability of collagen, by causing poor mechanical properties and rapid degradation, and their hard handling remains major challenges to be addressed. In this research, a composite structured nano‐/microfibrous scaffold, made from a mixture of chitosan–ß‐glycerol phosphate–gelatin (chitosan–GP–gelatin) using a standard electrospinning set‐up was developed. Gelatin–acid acetic and chitosan ß‐glycerol phosphate–HCL solutions were prepared at ratios of 30/70, 50/50, 70/30 (w/w) and their mechanical and biological properties were engineered. Furthermore, the pore structure of the fabricated nanofibrous scaffolds was investigated and predicted using a theoretical model. Higher gelatin concentrations in the polymer blend resulted in significant increase in mean pore size and its distribution. Interaction between the scaffold and the contained cells was also monitored and compared in the test and control groups. Scaffolds with higher chitosan concentrations showed higher rate of cell attachment with better proliferation property, compared with gelatin‐only scaffolds. The fabricated scaffolds, unlike many other natural polymers, also exhibit non‐toxic and biodegradable properties in the grafted tissues. In conclusion, the data clearly showed that the fabricated biomaterial is a biologically compatible scaffold with potential to serve as a proper platform for retaining the cultured cells for further application in cell‐based tissue engineering, especially in wound healing practices. These results suggested the potential of using mesoporous composite chitosan–GP–gelatin fibrous scaffolds for engineering three‐dimensional tissues with different inherent cell characteristics. © 2015 Wiley Periodicals, Inc. Biopolymers 105: 163–175, 2016. 相似文献
45.
Michal Brylinski Misagh Naderi Rajiv Gandhi Govindaraj Jeffrey Lemoine 《Journal of molecular biology》2018,430(15):2266-2273
About 7000 rare, or orphan, diseases affect more than 350 million people worldwide. Although these conditions collectively pose significant health care problems, drug companies seldom develop drugs for orphan diseases due to extremely limited individual markets. Consequently, developing new treatments for often life-threatening orphan diseases is primarily contingent on financial incentives from governments, special research grants, and private philanthropy. Computer-aided drug repositioning is a cheaper and faster alternative to traditional drug discovery offering a promising venue for orphan drug research. Here, we present eRepo-ORP, a comprehensive resource constructed by a large-scale repositioning of existing drugs to orphan diseases with a collection of structural bioinformatics tools, including eThread, eFindSite, and eMatchSite. Specifically, a systematic exploration of 320,856 possible links between known drugs in DrugBank and orphan proteins obtained from Orphanet reveals as many as 18,145 candidates for repurposing. In order to illustrate how potential therapeutics for rare diseases can be identified with eRepo-ORP, we discuss the repositioning of a kinase inhibitor for Ras-associated autoimmune leukoproliferative disease. The eRepo-ORP data set is available through the Open Science Framework at https://osf.io/qdjup/. 相似文献
46.
Marzieh Lotfi Hojjat Naderi‐Meshkin Elahe Mahdipour Asghar Mafinezhad Roohollah Bagherzadeh Hamid Reza Sadeghnia Habibollah Esmaily Masoud Maleki Halimeh Hasssanzadeh Majid Ghayaour‐Mobarhan Hamid Reza Bidkhori Ahmad Reza Bahrami 《Cell biology international》2019,43(12):1365-1378
Using cell‐based engineered skin is an emerging strategy for treating difficult‐to‐heal wounds. To date, much endeavor has been devoted to the fabrication of appropriate scaffolds with suitable biomechanical properties to support cell viability and growth in the microenvironment of a wound. The aim of this research was to assess the impact of adipose tissue‐derived mesenchymal stem cells (AD‐MSCs) and keratinocytes on gelatin/chitosan/β‐glycerol phosphate (GCGP) nanoscaffold in full‐thickness excisional skin wound healing of rats. For this purpose, AD‐MSCs and keratinocytes were isolated from rats and GCGP nanoscaffolds were electrospun. Through an in vivo study, the percentage of wound closure was assessed on days 7, 14, and 21 after wound induction. Samples were taken from the wound sites in order to evaluate the density of collagen fibers and vessels at 7 and 14 days. Moreover, sampling was done on days 7 and 14 from wound sites to assess the density of collagen fibers and vessels. The wound closure rate was significantly increased in the keratinocytes‐AD‐MSCs‐scaffold (KMS) group compared with other groups. The expressions of vascular endothelial growth factor, collagen type 1, and CD34 were also significantly higher in the KMS group compared with the other groups. These results suggest that the combination of AD‐MSCs and keratinocytes seeded onto GCGP nanoscaffold provides a promising treatment for wound healing. 相似文献
47.
S Naderi R Blomhoff J Myklebust E B Smeland B Erikstein K R Norum H K Blomhoff 《Experimental cell research》1999,252(1):144-153
Lovastatin is a potent inhibitor of protein prenylation, and it has been reported to have pleiotropic cellular effects. In the present study we have elucidated the effects of lovastatin on cell cycle progression and apoptosis of normal human B-lymphocytes. When added to B-lymphocytes stimulated with anti-immunoglobulin (anti-mu) and SAC, lovastatin (20 microM) inhibited the cells in the late G1 phase of the cell cycle. Thus, no early activation parameters such as Ca(2+) flux or MYC induction were affected by lovastatin, whereas progression of cells into the second cell cycle as well as DNA synthesis was markedly reduced. We therefore examined the effects of lovastatin on components of the cell cycle machinery responsible for regulating the G1/S transition. We demonstrated that pRB phosphorylation, cdk2 activity needed for this phosphorylation, and the levels of cyclin A, D, and E were inhibited after 24 h of lovastatin treatment, while the levels of p27(Kip1) were elevated. There was no effect on p21(Cip1), cyclin D2, cdk4, and cdk6. These data are consistent with the cells being inhibited by lovastatin between 24 and 32 h into G1. Lovastatin added to stimulated B-cells in late G1 still inhibited the DNA synthesis by 60%, but at this point only minor effects were noted on the cell cycle machinery. We therefore looked for induced apoptosis as an explanation for reduced S-phase entry of the cells. However, despite the ability to enhance the apoptosis of unstimulated B-cells from 48 to 61% as judged by the TUNEL method, lovastatin only marginally affected apoptosis when administered to stimulated B-cells. Thus, it appears that accelerated apoptosis cannot account for the effect of lovastatin on cell cycle progression. 相似文献
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49.
Local induction of acetylcholine receptor clustering in myotube cultures using microfluidic application of agrin 下载免费PDF全文
During neuromuscular synaptogenesis, the exchange of spatially localized signals between nerve and muscle initiates the coordinated focal accumulation of the acetylcholine (ACh) release machinery and the ACh receptors (AChRs). One of the key first steps is the release of the proteoglycan agrin focalized at the axon tip, which induces the clustering of AChRs on the postsynaptic membrane at the neuromuscular junction. The lack of a suitable method for focal application of agrin in myotube cultures has limited the majority of in vitro studies to the application of agrin baths. We used a microfluidic device and surface microengineering to focally stimulate muscle cells with agrin at a small portion of their membrane and at a time and position chosen by the user. The device is used to verify the hypothesis that focal application of agrin to the muscle cell membrane induces local aggregation of AChRs in differentiated C2C12 myotubes. 相似文献
50.