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81.
Muscle regeneration declines with aging and myopathies, and reprogramming of differentiated muscle cells to their progenitors can serve as a robust source of therapeutic cells. Here, we used the Cre-Lox method to specifically label postmitotic primary multinucleated myotubes and then utilized small molecule inhibitors of tyrosine phosphatases and apoptosis to dedifferentiate these myotubes into proliferating myogenic cells, without gene overexpression. The reprogrammed, fusion competent, muscle precursor cells contributed to muscle regeneration in?vitro and in?vivo and were unequivocally distinguished from reactivated reserve cells because of the lineage marking method. The small molecule inhibitors downregulated cell cycle inhibitors and chromatin remodeling factors known to promote and maintain the cell fate of myotubes, facilitating cell fate reversal. Our findings enhance understanding of cell-fate determination and create novel therapeutic approaches for improved muscle repair. 相似文献
82.
The present paper focused on the detection of methanol and propanol using Pd-gate metal-oxide-semiconductor (MOS) sensor. Surface mor- phology and composition of the gate film were studied by scanning electron microscopy (SEM) and atomic force microscopy (AFM). The response of the sensor for propanol and methanol was measured as shift in capacitance-voltage (C-V) and conductance-voltage (G-V) curves of the MOS structure. The sensitivity of the sensor towards methanol was found to be greater than that towards propanol. It was 58.2% for methanol and 32% for propanol (at 0.6 V, 1 MHz) in terms of capacitance measurements, while in terms of conductance results the sensitivity was found to be 57.2% for methanol and 38.9% for propanol at 1 kHz. The discontinuities or cracks present in the microstructure of the gate material are believed to be mainly responsible for the high sensitivity of the sensor, going with the decomposition of gas molecules and subsequent hydrogen permeation through Pd. 相似文献
83.
The synthesis of heterocyclic compounds containing pyrimidine, pyrazoline, isoxazoline and cyclohexenone ring from chalcone derivatives containing anisole and 3′4′-methylenedioxy phenyl ring under ‘dry conditions’ using microwaves and by conventional methods are described. 相似文献
84.
In this paper, the effect of nanostructures on the magnetic properties like the specific saturation magnetization (σS) and the coercivity (HC) for Mn0.4Zn0.6Fe2O4 ferrite prepared by the co-precipitation method has been presented. We have shown by means of X-ray diffraction that the resulting ferrite is made up of nanoparticles, and that the average size of these nanoparticles calculated with the Scherrer formula depends upon the sintering temperature. When the sintering temperature is increased from 500 to 900 °C, the average nanoparticle diameter varies from 19.3 to 36.4 nm. The nanoparticle phase is further confirmed by scanning electron microscopy (SEM). Both results are found to be in good agreement. The magnetic properties are explained on the basis of the single-domain and multi-domain theory. 相似文献
85.
We study the effect of momentum-dependent interactions and a broader Gaussian on multifragmentation. We also look into the details of the fragment structure for a broader Gaussian and momentum-dependent interactions. We find that nucleons forming the fragments belong to the same region of the phase space. 相似文献
86.
Javed Intekhab Mohammad Aslam Vivek Bhadauria Preeti Singh 《Chemistry of Natural Compounds》2012,48(4):568-569
From the ethyl acetate extract of the roots of Clausena pentaphylla, a flavanone glycoside, 5,7-dihydroxy3',4'-dimethoxyflavanone 6-C-[α-rhamnopyranosyl-(1 → 6)]-β-glucopyranoside (1), was isolated. The isolated compound was characterized by UV, IR, and NMR (1H, 13C) studies. 相似文献
87.
88.
We address the dielectric behavior in a free standing spherical particle using the phenomenological Landau theory. Considering the equations of motion and small perturbation against uniform polarization, we obtain the size driven ferroelectricity. The size driven polarization is shown to diverge at a new correlation length which turns out to be the extrapolation length. Mode analysis in such systems is carried out and it is found that the size driven ferroelectricity is associated with a soft mode which takes a minimum value at the new transition temperature similar to that of the bulk system. We suggested that such a mode can be tested in Raman measurement. 相似文献
89.
High safety, robust efficacy, and rapid onset of action remain the key challenges for improving antidepressant drug discovery. We report a facile and efficient synthetic strategy to structurally encompass mono-, di-, or tri-substituted derivatives using cyanuric chloride and various substituted phenylthiazole-2-amines. The predicted physicochemical property precisely state their specificity as CNS acting agent and antidepressant-like effect of the most promising compound 10 after oral administration significantly reduced immobility in mice behavior models, especially TST from 63 s. In addition, good safety features of 10 highlight its ability to modulate hallmarks for antidepressant discovery. These insights are useful in generalization and systematization of CRF1 antagonist design to develop future biological end points. 相似文献
90.
Har Mohindra Chawla Preeti Goel Richa Shukla David StC Black Naresh Kumar 《Journal of inclusion phenomena and macrocyclic chemistry》2014,80(3-4):201-207
A new calix[4]arene derivative in its cone conformation and bearing Schiff base loop at the lower rim has been synthesized and evaluated as a specific molecular probe for copper ions. The new molecular receptor 4 shows a selective visible change in color from colorless to yellow only in the presence of Cu2+ ions which was confirmed by a significant bathochromic shift (?λmax = 76 nm) in its absorption spectrum. The stoichiometry of the copper complex was calculated to be 1:1. These results may help to design more efficient chemical sensors for determining copper in biological systems. 相似文献