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Mesenchymal stem cells (MSCs) obtained from various sources have been used for different therapeutic applications including tissue regeneration. Reamer/irrigator/aspirator (RIA) has been increasingly used in recent years for the derivation of MSCs. Here in this investigation we have comparatively analyzed MSCs obtained from iliac crest bone marrow (ICBM) and RIA for their morphology, cluster determinant (CD) markers, and adipogenic differentiation capacity. MSCs were isolated, cultured, and purified from both sources and then flow cytometric studies were performed to study their characteristics. The differentiation potential of RIA and ICBM was examined by an Oil Red O staining protocol. Moreover, the tissue-specific markers related to adipogenesis were analyzed by real-time polymerase chain reaction (RT-PCR). The cells were cultured in the relevant induction medium and then adipogenic lineage differentiation was tested and confirmed for all MSC preparations. Additionally, analysis by flow cytometer was indicative of RIA derived MSCs (RIA-MSCs) having a more homogenous population than ICBM derived MSCs. The RIA-MSCs differentiation toward adipogenic lineage was more efficient compared with ICBM-MSCs. Direct comparative analysis of RIA to ICBM-MSCs indicated that the RIA-MSCs had a higher potential toward adipocyte lineage differentiation compared with ICBM-MSCs.  相似文献   
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As major chaperone of eye lens, alpha-crystallin (α-Crs) is responsible for the transparency and refractive power of this region by preventing denaturation and precipitation of other proteins. As shown previously, cataract formation was positively associated with high salt intake and the elevation of blood sugar level. Here the effect of both temperature and ionic strength were studied on structure and chaperoning function of glycated and non-glycated α-Crs. While chaperone activity of these proteins was increased as function of temperature elevation, in the presence of sodium salt (0- 160 mM), it was significantly decreased. As shown by fluorescence and circular dicroism (CD) instruments, the salt induced structural alteration of α-Crs was accompanied with the exposure of hydrophobic surfaces and a transition from alpha- helical to beta-sheet structures. Moreover, the structural alterations induced by the salt were more pronounced in the case of glycated α-Crs compared to that of non-glycated protein counterpart. Overall this study shows the structural changes accompanied with lose of the chaperone activity of α-Crs induced by sodium chloride. Consequently, the obtained results may provide new evidences for the relationship between high salt intakes and cataract disease induced particularly by prolonged hyperglycemia.  相似文献   
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The beginnings of agriculture throughout the Fertile Crescent are still not completely understood, particularly at the eastern end of the Fertile Crescent in the area of modern Iran. Archaeobotanical samples from Epipalaeolithic/PPNA Körtik Tepe in southeastern Turkey and from the Pre-Pottery Neolithic sites of Chogha Golan and East Chia Sabz in south western Iran were studied in order to define the status of cultivation at these sites. Preliminary results show the presence of abundant wild progenitor species of crops at the Iranian sites before 10600 cal. b.p., and very few wild progenitor species at Körtik Tepe dated to 11700–11250 cal. b.p. The Iranian sites also indicate size increase of wild barley grain across a sequence of 400 years through either cultivation or changing moisture conditions.  相似文献   
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Background and Aims: Helicobacter pylori is a highly diverse pathogen, which encounters epithelial cells as the initial defense barrier during its lifelong infection. The structure of epithelial cells can be disrupted through cleavage of microfilaments. Cytokeratin 18 (CK18) is an intermediate filament, the cleavage of which is considered an early event during apoptosis following activation of effector caspases. Methods: Helicobacter pylori strains were isolated from 76 dyspeptic patients. cagA 3’ variable region and CagA protein status were analyzed by PCR and western blotting, respectively. Eight hours post‐co‐culture of AGS cells with different H. pylori strains, flow cytometric analysis was performed using M30 monoclonal antibody specific to CK18 cleavage‐induced neo‐epitope. Results: Higher rates of CK18 cleavage were detected during co‐culture of AGS cells with H. pylori strains bearing greater numbers of cagA EPIYA‐C and multimerization (CM) motifs. On the other hand, H. pylori strains with greater numbers of EPIYA‐B relative to EPIYA‐C demonstrated a decrease in CK18 cleavage rate. Thus, H. pylori‐mediated cleavage of CK18 appeared proportional to the number of CagA EPIYA‐C and CM motifs, which seemed to be downplayed in the presence of EPIYA‐B motifs. Conclusions: Our observation associating the heterogeneity of cagA variants with the potential of H. pylori strains in the induction of CK18 cleavage as an early indication of apoptosis in gastric epithelial cells supports the fact that apoptosis may be a type‐specific trait. However, additional cagA‐targeted experiments are required to clearly identify the role of EPIYA and CM motifs in apoptosis and/or the responsible effector molecules.  相似文献   
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Recent advances in wound healing have made cell therapy a potential approach for the treatment of various types of skin defects such as trauma, burns, scars and diabetic leg ulcers. Cultured keratinocytes have been applied to burn patients since 1981. Patients with acute and chronic wounds can be treated with autologous/allograft cultured keratinocytes. There are various methods for cultivation of epidermal keratinocytes used in cell therapy. One of the important properties of an efficient cell therapy is the preservation of epidermal stem cells. Mesenchymal Stem Cells (MSCs) are major regulatory cells involved in the acceleration of wound healing via induction of cell proliferation, angiogenesis and stimulating the release of paracrine signaling molecules. Considering the beneficial effects of MSCs on wound healing, the main aim of the present study is investigating paracrine effects of Adipose-derived Mesenchymal Stem Cell (Ad-MSCs) on cultivation of keratinocytes with focusing on preservation of stem cells and their differentiation process. We further introduced a new approach for culturing isolated keratinocytes in vitro in order to generate epidermal keratinocyte sheets without using a feeder layer. To do so, Ad-MSC conditioned medium was applied as an alternative to commercial media for keratinocyte cultivation. In this study, the expression of several stem/progenitor cell (P63, K19 and K14) and differentition (K10, IVL and FLG) markers was examined using real time PCR on days 7, 14 and 21 of culture in keratinocytes in Ad-MSC conditioned medium. P63 and α6 integrin expression was also evaluated via flow cytometry. The results were compared with control group including keratinocytes cultured in EpiLife medium and our data indicated that this Ad-MSC conditioned medium is a good alternative for keratinocyte cultivation and producing epidermal sheets for therapeutic and clinical purposes. The reasons are the expression of stem cell and differentiation markers and overcoming the requirement for feeder layer which leads to a xenograft-free transplantation. Besides, this approach has low cost and is easier to perform. However, more in vitro and in vivo experiments as well as safety evaluation required before clinical applications.  相似文献   
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Bioprocess and Biosystems Engineering - In this study, we synthesized super magnetic Fe(OH)3@Fe3O4 nanoparticles (SPIONs) by the co-precipitation method and introduction of amine groups via...  相似文献   
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Considering the self‐renewal and differentiation ability of pluripotent stem cells, some studies have pointed out the possibility of stem cell‐derived sperm production. Most studies that test this hypothesis have been conducted on rodents, with some promising results; however, studies on humans are progressing slowly, and have encountered technical and ethical hurdles. Established methods to differentiate stem cells—including embryoid bodies, co‐culturing, and various feeder cells—may provide a niche that is similar to in vivo conditions and resolve epigenetic abnormalities, but a gonadal‐like three‐dimensional structure is still required to produce germ cells with the correct imprinting. In the last few years, sperm‐like cells with fertilizing capacity were produced from mouse embryonic stem cells, and the resulting embryos from these cells yielded live offspring. Future research should move towards the use of adult stem cells, however, owing to the unavailability of embryonic cells in adults. More intensive research and techniques are required since in vitro spermatogenesis provides hope to individuals without mature sperm who cannot be treated, and may be a useful system to study the precise mechanism of spermatogenesis. In this review, we describe recent studies of in vitro spermatogenesis mechanisms and related techniques in mammals. We also discuss the possible cell surface markers and culture conditions that might improve in vitro spermatogenesis.  相似文献   
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