Spontaneous Cardiomyocyte Differentiation From Adipose Tissue Stroma Cells

Cardiomyocyte regeneration is limited in adult life. Thus, the identification of a putative source of cardiomyocyte progenitors is of great interest to provide a usable model in vitro and new perspective in regenerative therapy. As adipose tissues were recently demonstrated to contain pluripotent stem cells, the emergence of cardiomyocyte phenotype from adipose-derived cells was investigated. We demonstrated that rare beating cells with cardiomyocyte features could be identified after culture of adipose stroma cells without addition of 5-azacytidine. The cardiomyocyte phenotype was first identified by morphological observation, confirmed with expression of specific cardiac markers, immunocytochemistry staining, and ultrastructural analysis, revealing the presence of ventricle- and atrial-like cells. Electrophysiological studies performed on early culture revealed a pacemaker activity of the cells. Finally, functional studies showed that adrenergic agonist stimulated the beating rate whereas cholinergic agonist decreased it. Taken together, this study demonstrated that functional cardiomyocyte- like cells could be directly obtained from adipose tissue. According to the large amount of this tissue in adult mammal, it could represent a useful source of cardiomyocyte progenitors.Garcia Verdugo, Jose Manuel, [email protected]

Studies of Vibrational Properties in Ga Stabilized d-Pu by Extended X-ray Absorption Fine Structure

Temperature dependent extended x-ray absorption fine structure (EXAFS) spectra were measured for a 3.3 at% Ga stabilized Pu alloy over the range T= 20 - 300 K at both the Ga K-edge and the Pu L_III-edge. The temperature dependence of the pair-distance distribution widths, \sigma(T) was accurately modeled using a correlated-Debye model for the lattice vibrational properties, suggesting Debye-like behavior in this material. We obtain pair- specific correlated-Debye temperatures, \Theta_cD, of 110.7 +/- 1.7 K and 202.6 +/- 3.7 K, for the Pu-Pu and Ga-Pu pairs, respectively. These results represent the first unambiguous determination of Ga-specific vibrational properties in PuGa alloys, and indicate the Ga-Pu bonds are significantly stronger than the Pu-Pu bonds. This effect has important implications for lattice stabilization mechanisms in these alloys.Comment: 7 pages, 4 figures, Phys. Rev. B in pres

Far-infrared study of the Jahn-Teller distorted C60 monoanion in C60 tetraphenylphosphoniumiodide

We report high-resolution far-infrared transmission measurements on C(60)-tetraphenylphosphoniumiodide as a function of temperature. In the spectral region investigated (20-650 cm(-1)), we assign intramolecular modes of the C(60) monoanion and identify low-frequency combination modes. The well-known F(1u)(1) and F(1u)(2) modes are split into doublers at room temperature, indicating a D(5d) or D(3d) distorted ball. This result is consistent with a dynamic Jahn-Teller effect in the strong-coupling limit or with a static distortion stabilized by low-symmetry perturbations. The appearance of silent odd modes is in keeping with symmetry reduction of the hall, while activation of even modes is attributed to interband electron-phonon coupling and orientational disorder in the fulleride salt. Temperature dependences reveal a weak transition in the region 125-150 K in both C(60)(-) and counterion modes, indicating a bulk, rather than solely molecular, effect. Anomalous softening (with decreasing temperature) in several modes may correlate with the radial character of those vibrations. [S0163-1829(98)03245-7]

Does congenital deafness affect the structural and functional architecture of primary visual cortex?

Deafness results in greater reliance on the remaining senses. It is unknown whether the cortical architecture of the intact senses is optimized to compensate for lost input. Here we performed widefield population receptive field (pRF) mapping of primary visual cortex (V1) with functional magnetic resonance imaging (fMRI) in hearing and congenitally deaf participants, all of whom had learnt sign language after the age of 10 years. We found larger pRFs encoding the peripheral visual field of deaf compared to hearing participants. This was likely driven by larger facilitatory center zones of the pRF profile concentrated in the near and far periphery in the deaf group. pRF density was comparable between groups, indicating pRFs overlapped more in the deaf group. This could suggest that a coarse coding strategy underlies enhanced peripheral visual skills in deaf people. Cortical thickness was also decreased in V1 in the deaf group. These findings suggest deafness causes structural and functional plasticity at the earliest stages of visual cortex

Correlation Effects on Stability in Pu Metal and Its Alloys

The existence of six crystallographic allotropes from room temperature up to the solid-liquid transition just above 913 K at atmospheric pressure makes solid Plutonium unique among the elements in the periodic table. Among these phases (labeled {alpha}, {beta}, {gamma}, {delta}{delta}{prime}), and {var_epsilon}, the {delta} phase, stable between 593 K and 736 K, has commanded considerable interest in the metallurgical and solid state communities. In contrast to the low-temperature monoclinic {alpha} phase, which is brittle, the face-centered cubic (fcc) {delta} phase is ductile, a property that makes it convenient for engineering applications. This phase can also be stabilized through alloying with a number of other elements such as Ga, Al, Sc, and Am

Mitochondrial ROS metabolism: modulation by uncoupling proteins

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