Synthesis of Some New Thienylazetidinones and Thiazolidinones Containing Pyrazolines

Condensation of thiophene-2-carboxa.ldehyde with 4-aminoacetophenone gave a quantitative yield of 4-(thienylideneamino)acetophenone( I). Condensation of I with aromatic aldehydes yielded the corresponding 4-( 4-substituted-phenyl)-4\u27 -(2-thienyleneamino )chalcone( II). Interaction of II with hydrazines gave 3-(4-2\u27-thienylideneamino) phenylpyrazolines (III, IV). Cyclocondensation of chloroacetyl chloride (or mercaptoa cetic acid) on III or IV gave 3-chloro-1-( 4-pheny lpyrazolin-3\u27 -yl)-4-(2" - thieny l)azetidin -2- ones (V, VI) and 3-(4-phenylpyrazolin-3\u27-yl)-2-(2"-thienyl)thiazolidin-4- -ones (VII, VIII), respectivel

Regulation of Osteogenic Differentiation of Placental-Derived Mesenchymal Stem Cells by Insulin-Like Growth Factors and Low Oxygen Tension

Placental mesenchymal stem cells (PMSCs) are multipotent cells that can differentiate in vitro to multiple lineages, including bone. Insulin-like growth factors (IGFs, IGF-1 and IGF-2) participate in maintaining growth, survival, and differentiation of many stem cells, including osteoprogenitors. Low oxygen tension (PO2) can maintain stem cell multipotency and impede osteogenic differentiation. In this study, we investigated whether PMSC osteogenic differentiation is influenced by low PO2 and by IGFs. Our results indicated that low PO2 decreased osteogenic markers RUNX2 and OPN; however, re-exposure to higher oxygen tension (room air) restored differentiation. IGFs, especially IGF-1, triggered an earlier expression of RUNX2 and enhanced OPN and mineralization. RUNX2 was phosphorylated in room air and augmented by IGFs. IGF-1 receptor (IGF-1R) was increased in low PO2 and reduced by IGFs, while insulin receptor (IR) was increased in differentiating PMSCs and enhanced by IGF-1. Low PO2 and IGFs maintained higher IR-A which was switched to IR-B in room air. PI3K/AKT was required for osteogenic differentiation, while MEK/ERK was required to repress an RUNX2 and OPN increase in low PO2. Therefore, IGFs, specifically IGF-1, trigger the earlier onset of osteogenic differentiation in room air, whereas, reversibly, low PO2 impedes complete differentiation by maintaining higher multipotency and lower differentiation markers

Generalized β\beta-conformal change and special Finsler spaces

In this paper, we investigate the change of Finslr metrics $$L(x,y) \to\bar{L}(x,y) = f(e^{\sigma(x)}L(x,y),\beta(x,y)),$$ which we refer to as a generalized $\beta$-conformal change. Under this change, we study some special Finsler spaces, namely, quasi C-reducible, semi C-reducible, C-reducible, $C_2$-like, $S_3$-like and $S_4$-like Finsler spaces. We also obtain the transformation of the T-tensor under this change and study some interesting special cases. We then impose a certain condition on the generalized $\beta$-conformal change, which we call the b-condition, and investigate the geometric consequences of such condition. Finally, we give the conditions under which a generalized $\beta$-conformal change is projective and generalize some known results in the literature.Comment: References added, some modifications are performed, LateX file, 24 page

The Roles of Insulin-Like Growth Factors in Mesenchymal Stem Cell Niche

Many tissues contain adult mesenchymal stem cells (MSCs), which may be used in tissue regeneration therapies. However, the MSC availability in most tissues is limited which demands expansion in vitro following isolation. Like many developing cells, the state of MSCs is affected by the surrounding microenvironment, and mimicking this natural microenvironment that supports multipotent or differentiated state in vivo is essential to understand for the successful use of MSC in regenerative therapies. Many researchers are, therefore, optimizing cell culture conditions in vitro by altering growth factors, extracellular matrices, chemicals, oxygen tension, and surrounding pH to enhance stem cells self-renewal or differentiation. Insulin-like growth factors (IGFs) system has been demonstrated to play an important role in stem cell biology to either promote proliferation and self-renewal or enhance differentiation onset and outcome, depending on the cell culture conditions. In this review, we will describe the importance of IGFs, IGF-1 and IGF-2, in development and in the MSC niche and how they affect the pluripotency or differentiation towards multiple lineages of the three germ layers

Genetic trend in selection for litter weight in two maternal lines of rabbits in Egypt

[EN] An analysis was carried out to evaluate the results of the selection program of a new synthetic maternal line of Egyptian APRI rabbits and the Spanish V line. The selection criterion was litter weaning weight in both lines based on Best Linear Unbiased Prediction (BLUP) estimations under a repeatability animal model. The studied traits were: litter birth weight, litter weaning weight (at 28 d) and pre-weaning litter gain. Heritability estimates were generally low (0.09 to 0.11) and comparable in both lines. Low to moderate estimates of repeatability were observed for all studied traits (0.15 to 0.31). Estimates of genetic correlations were high (0.77 to 0.97), while permanent environmental effects correlations were mostly lower than genetic correlations (0.47 to 0.87). The genetic trends were also estimated using mixed model methodology and were significant and comparable (34.2 and 32.5 g) for the selected trait (litter weaning weight) in APRI and V lines, respectively. Furthermore, correlated genetic trends were significant (P<0.05) for other litter weight traits. These results indicate that the current selection program has been effective in achieving genetic improvement in litter weight traits.The authors would like to thank the Spanish Agency of International Cooperation for supporting this work through the project “Sustainable production of rabbit meat: Evaluation and genetic improvement of Spanish-Egyptian rabbit lines”.Abou Khadiga, G.; Youssef, Y.; Saleh, K.; Nofal, R.; Baselga, M. (2010). Genetic trend in selection for litter weight in two maternal lines of rabbits in Egypt. World Rabbit Science. 18(1):27-32. doi:10.4995/wrs.2010.18.04273218

THE EFFECTS OF TEMPERATURE DEPENDENT VISCOSITY AND VISCOUS DISSIPATION ON MHD CONVECTION FLOW FROM AN ISOTHERMAL HORIZONTAL CIRCULAR CYLINDER IN THE PRESENCE OF STRESS WORK AND HEAT GENERATION

Temperature dependent viscosity and Viscous Dissipation effects are considered on hydromagnetic natural convection flow from horizontal circular cylinder immersed in an electrically conducting fluid with viscosity proportional to a linear function of temperature in the presence of stress work and heat generation. The partial differential governing equations are transformed to dimensionless forms. The numerical computations are carried out for several values of physical parameters involved in the transformed equations. The resulting nonlinear system of partial differential equations is solved numerically by Keller box method which is an implicit finite difference technique with Newton's linearization method. The features of the flow and heat transfer characteristics for different values of the governing parameters are analyzed and discussed. To support the accuracy of the numerical results, a comparison is made with known results from the open literature for some particular cases of the present study and the results are found to be in good agreement

The Casimir force in noncommutative Randall-Sundrum models

In this paper we study the effect of spacetime noncommutativity in the 5-dimensional Randall-Sundrum brane worlds on the Casimir force acting on a pair of parallel plates. We show that the presence of a noncommutative scale length affects the nature of the Casimir force for small plate separation. Using accurate experimental bounds for the Casimir force in parallel plate geometry, we find an upper bound for the noncommutative cutoff of the order of $10^{3}$ TeV, and that the size of the interbrane distance in RSI model is approximately given by $kR\lesssim20.5$ and $kR\lesssim18.4$ for $k=10^{19}$ GeV and $k=10^{16}$GeV, respectively.Comment: 20 pages, 5 figures, accepted for publication in Phys. Rev.