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1.
Differentiation of embryonic stem cell (ESC)-derived embryoid bodies (EBs) is a heterogeneous process. ESCs can differentiate
in vitro into different cell types including beating cardiomyocytes. The main aim of the present study was to develop an improved
preparation method for scanning electron microscopic study of ESC-derived cardiac bundles and to investigate the fine structural
characteristics of mouse ESCs-derived cardiomyocytes using electron microscopy. The mouse ESCs differentiation was induced
by EBs’ development through hanging drop, suspension and plating stages. Cardiomyocytes appeared in the EBs’ outgrowth as
beating clusters that grew in size and formed thick branching bundles gradually. Cardiac bundles showed cross striation even
when they were observed under an inverted microscope. They showed a positive immunostaining for cardiac troponin I and α-actinin.
Transmission and scanning electron microscopy (TEM & SEM) were used to study the structural characteristics of ESC-derived
cardiomyocytes. Three weeks after plating, differentiated EBs showed a superficial layer of compact fibrous ECM that made
detailed observation of cardiac bundles impossible. We tried several preparation methods to remove unwanted cells and fibers,
and finally we revealed the branching bundles of cardiomyocytes. In TEM study, most cardiomyocytes showed parallel arrays
of myofibrils with a mature sarcomeric organization marked by H-bands, M-lines and numerous T-tubules. Cardiomyocytes were
connected to each other by intercalated discs composed of numerous gap junctions and fascia adherences. 相似文献
2.
ABSTRACTThis study was conducted to assess the effect of feeding high-surface ZnO instead of common ZnO on the performance, rumen fermentation, blood minerals, leukocytes and antioxidant capacity of pre- and post-weaning calves. Thirty male suckling Holstein calves were allotted to one of three experimental groups (10 replicates) in a completely randomised design. Calves received: (1) a low Zn diet without Zn supplementation (control diet), (2) a high Zn diet containing 50 mg supplementary Zn/kg dry matter (DM) as common ZnO or (3) a high Zn diet containing 50 mg supplementary Zn/kg DM as high-surface ZnO (nano-ZnO). The control diet contained a native Zn content of 35.5, 34.7 or 33.7 mg/kg DM for the age periods of 7 to 30, 31 to 70 and 71 to 100 d, respectively. Supplementation of the diet with Zn did not change the dry matter intake (DMI) of calves during d 7 to 30 but increased the ADG in this period (p < 0.05). During age periods of 31 to 70 and 71 to 100 d, DMI and ADG of the Zn supplemented calves were higher (p < 0.05) than the control animals. The nutrient digestibility and the concentration of rumen volatile fatty acids were positively affected (p < 0.05) and the rumen ammonia-N concentration decreased (p < 0.05) by dietary Zn supplementation. Furthermore, the incidence of diarrhoea and pneumonia was lower in calves receiving the Zn supplemented diets. Irrespective of ZnO source, the blood total antioxidant capacity, leukocyte and haematocrit levels significantly increased (p < 0.05) with the ZnO supplemented diets. The post-weaning DMI, nutrient digestibility and blood haematocrit levels were higher in calves receiving high-surface ZnO, compared to those supplemented with common ZnO. With inclusion of the Zn sources in pre- and post-weaning diets, the blood Zn concentration increased (p < 0.05), but the blood Cu, Fe, Ca, P and Mg levels remained unchanged. Regardless of source, dietary supplementation of young calves with ZnO improved the performance and decreased rumen ammonia-N and the incidence of diseases. Moreover, high-surface ZnO had advantages over common ZnO in increasing the post-weaning feed intake, digestibility and blood Zn concentration. 相似文献
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Seied Mojtaba Valiahdi Alexander E. Egger Walter Miklos Ute Jungwirth Kristof Meelich Petra Nock Walter Berger Christian G. Hartinger Markus Galanski Michael A. Jakupec Bernhard K. Keppler 《Journal of biological inorganic chemistry》2013,18(2):249-260
Extracellular acidity is a frequent pathophysiological condition of solid tumors offering possibilities for improving the tumor selectivity of molecular therapy. This might be accomplished by prodrugs with low systemic toxicity, attaining their full antitumor potency only under acidic conditions, such as bis(2-aminoalcoholato-κ²N,O)platinum(II) complexes that are activated by protonation of alcoholato oxygen, resulting in cleavage of platinum–oxygen bonds. In this work, we examined whether the pH dependency of such compounds is reflected in differential biological activity in vitro. In particular, the pH dependence of cytotoxicity, cellular accumulation, DNA platination, GMP binding, effects on DNA secondary structure, cell cycle alterations, and induction of apoptosis was investigated. Enhanced cytotoxicity of five of these complexes in non-small-cell lung cancer (A549) and colon carcinoma (HT-29) cells at pH 6.0 in comparison with pH 7.4 was confirmed: 50 % growth inhibition concentrations ranged from 42 to 214 μM in A549 cells and from 35 to 87 μM in HT-29 cells at pH 7.4 and decreased at pH 6.0 to 11–50 and 7.3–25 μM, respectively. The effects induced by all five pH-sensitive compounds involve increased 5′-GMP binding, cellular accumulation, and DNA platination as well as stronger effects on DNA secondary structure at pH 6.0 than at pH 7.4. As exemplified by treatment of A549 cells with a 2-amino-4-methyl-1-pentanolato complex, induction of apoptosis is enhanced at pH 6.5. These results confirm the increased reactivity and in vitro activity of these compounds under slightly acidic conditions, encouraging further evaluation of ring-closed aminoalcoholatoplatinum(II) derivatives in solid tumors in vivo. 相似文献
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Narges Riahi Amirhosein Kefayat Ahmad Ghasemi Mohammadhosein Asgarshamsi Mojtaba Panjehpoor Afshin Fassihi 《化学与生物多样性》2019,16(2)
Eight derivatives of tetrahydropyrimidine scaffold were designed and prepared as hybrid compounds possessing the structural features of both monastrol as an anticancer drug and nifedipine as a fascin blocking agent. All of the compounds were evaluated for their cytotoxic potency and the ability to inhibit 4T1 breast cancer cells migration. Then, they were investigated in silico for their ability to inhibit the fascin protein using molecular docking simulation. The most potent compound was 4d and the weakest one was 4a according to the in vitro cytotoxicity assay. The corresponding IC50 values were 193.70 and 248.75 μm , respectively. The least cytotoxic compound ( 4a ) was one of the strongest ones in binding to the fascin binding site according to the molecular docking results. 4a and 4e inhibited the 4T1 cells migration better than other compounds. They were more potent than nifedipine in inhibiting the migration process. In silico studies proved 4h to be the most potent fascin inhibitor in terms of ΔGbind although it was not inhibiting migration. The controversy between the in vitro and in silico results may cancel the theory of the involvement of the fascin inhibition in the migration inhibition. However, the considerable antimigratory effects of some of the synthesized compounds encourage performing further in vivo experiments to introduce novel tumor metastasis inhibitors. 相似文献
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A new species of pseudoscorpion, Amblyolpium atropatesi n. sp. is described and illustrated on the basis of the adult specimens extracted from soil by Berlese funnel.
http://www.zoobank.org/urn:lsid:zoobank.org:pub:0150B850-E80D-46F5-983C-7E958FE69B87 相似文献
9.
Aynaz Mihanfar Javad Aghazadeh Attari Iraj Mohebbi Maryam Majidinia Mojtaba Kaviani Mehdi Yousefi Bahman Yousefi 《Journal of cellular physiology》2019,234(4):3238-3253
The cancer stem cell (CSC) model encompasses an advantageous paradigm that in recent decades provides a better elucidation for many important biological aspects of cancer initiation, progression, metastasis, and, more important, development of multidrug resistance (MDR). Such several other hematological malignancies and solid tumors and the identification and isolation of ovarian cancer stem cells (OV-CSCs) show that ovarian cancer also follows this hierarchical model. Gaining a better insight into CSC-mediated resistance holds promise for improving current ovarian cancer therapies and prolonging the survival of recurrent ovarian cancer patients in the future. Therefore, in this review, we will discuss some important mechanisms by which CSCs can escape chemotherapy, and then review the recent and growing body of evidence that supports the contribution of CSCs to MDR in ovarian cancer. 相似文献
10.
Anvar Soleimani Amirhossein Bahreyni Mostafa K. Roshan Arash Soltani Mikhail Ryzhikov Mojtaba Shafiee Mohammad Soukhtanloo Mahmoud R. Jaafari Baratali Mashkani Seyed M. Hassanian 《Journal of cellular physiology》2019,234(3):2329-2336
The hypoxic niche of tumor leads to a tremendous increase in the extracellular adenosine concentration through alteration of adenosine metabolism in the tumor microenvironment (TME). This consequently affects cancer progression, local immune responses, and apoptosis of tumor cells. Regulatory effect of adenosine on apoptosis in TME depends on the cancer cell type, pharmacological characteristics of adenosine receptor subtypes, and the adenosine concentration in the tumor niche. Exploiting specific pharmacological adenosine receptor agonist and antagonist inducing apoptosis in cancer cells can be considered as a proper procedure to control cancer progression. This review summarizes the regulatory role of adenosine in cancer cell apoptosis for a better understanding, and hence better management of the disease. 相似文献