Chiara Villa, Silvia Erratico, Paola Razini, Fabrizio Fiori, Franco Rustichelli, Yvan Torrente and Marzia Belicchi
Review: Stem Cell Tracking by Nanotechnologies
Int. J. Mol. Sci. 2010, 11(3), 1070-1081; doi:10.3390/ijms11031070 - published online 12 March 2010
Show/Hide AbstractAbstract: Advances in stem cell research have provided important understanding of the cell biology and offered great promise for developing new strategies for tissue regeneration. The beneficial effects of stem cell therapy depend also by the development of new approachs for the track of stem cells in living subjects over time after transplantation. Recent developments in the use of nanotechnologies have contributed to advance of the high-resolution in vivo imaging methods, including positron emission tomography (PET), single-photon emission tomography (SPECT), magnetic resonance (MR) imaging, and X-Ray computed microtomography (microCT). This review examines the use of nanotechnologies for stem cell tracking.

Teh Ban Hong, Anizah Rahumatullah, Thaneswary Yogarajah, Maimunah Ahmad and Khoo Boon Yin
Article: Potential Effects of Chrysin on MDA-MB-231 Cells
Int. J. Mol. Sci. 2010, 11(3), 1057-1069; doi:10.3390/ijms11031057 - published online 11 March 2010
Show/Hide AbstractAbstract: This study aims to elucidate the effects of chrysin on human ER-negative breast cancer cell line, MDA-MB-231. The study demonstrated that treatment of MDA-MB-231 cells with 20 µM chysin for 48 h significantly inhibited the growth of MDA-MB-231 cells and induced cytoplasmic lipid accumulation in the cells, but that the observed of cell death was not caused by apoptosis. The expression of PPARalpha mRNA in chrysin-treated MDA-MB-231 cells was significantly increased, which was likely associated to the proliferation of the cells post chrysin treatment.

Chunmei Gu, Hongbin Pan, Zewei Sun and Guixin Qin
Article: Effect of Soybean Variety on Anti-Nutritional Factors Content, and Growth Performance and Nutrients Metabolism in Rat
Int. J. Mol. Sci. 2010, 11(3), 1048-1056; doi:10.3390/ijms11031048 - published online 9 March 2010
Show/Hide AbstractAbstract: The present study was undertaken to evaluate the effects of soybean varieties on content of anti-nutritional factors, growth, and nutrient digestibility in rat. For this purpose, the content of trypsin inhibitor and lectin was firstly measured in five soybean varieties. Then sixty male Wistar rats were randomly divided into six groups and fed on different diets as follows: groups 1 to 5 were fed on treatment diets containing five different varieties of soybean flour; group 6 was fed on a control diet containing casein. All animals were fed for four weeks. During this period, faeces and urine were collected to determine the nutritional efficiency of diets and body weight were measured weekly on ten rats from each group. The results showed that trypsin inhibitor and lectin content of Jilin45 was the highest, and those of Jinong7 were the lowest of the soybean varieties. In comparison, all measured parameters, that is including gain in body weight, feed utilization efficiency, nutrient digestibility, nitrogen balance and nitrogen retention, were markedly different among the five groups of animals, but were significantly lower than the control group. These findings show that soybean varieties could significantly affect trypsin inhibitor and lectin content in soybean.

Jiwei Hu, Xiaoyi Zhang and Zhengwu Wang
Review: A Review on Progress in QSPR Studies for Surfactants
Int. J. Mol. Sci. 2010, 11(3), 1020-1047; doi:10.3390/ijms11031020 - published online 8 March 2010
Show/Hide AbstractAbstract: This paper presents a review on recent progress in quantitative structure-property relationship (QSPR) studies of surfactants and applications of various molecular descriptors. QSPR studies on critical micelle concentration (cmc) and surface tension (γ) of surfactants are introduced. Studies on charge distribution in ionic surfactants by quantum chemical calculations and its effects on the structures and properties of the colloids of surfactants are also reviewed. The trends of QSPR studies on cloud point (for nonionic surfactants), biodegradation potential and some other properties of surfactants are evaluated .

Rita Guzun and Valdur Saks
Review: Application of the Principles of Systems Biology and Wiener's Cybernetics for Analysis of Regulation of Energy Fluxes in Muscle Cells in Vivo
Int. J. Mol. Sci. 2010, 11(3), 982-1019; doi:10.3390/ijms11030982 - published online 8 March 2010
Show/Hide AbstractAbstract: The mechanisms of regulation of respiration and energy fluxes in the cells are analyzed based on the concepts of systems biology, non-equilibrium steady state kinetics and applications of Wiener’s cybernetic principles of feedback regulation. Under physiological conditions cardiac function is governed by the Frank-Starling law and the main metabolic characteristic of cardiac muscle cells is metabolic homeostasis, when both workload and respiration rate can be changed manifold at constant intracellular level of phosphocreatine and ATP in the cells. This is not observed in skeletal muscles. Controversies in theoretical explanations of these observations are analyzed. Experimental studies of permeabilized fibers from human skeletal muscle vastus lateralis and adult rat cardiomyocytes showed that the respiration rate is always an apparent hyperbolic but not a sigmoid function of ADP concentration. It is our conclusion that realistic explanations of regulation of energy fluxes in muscle cells require systemic approaches including application of the feedback theory of Wiener’s cybernetics in combination with detailed experimental research. Such an analysis reveals the importance of limited permeability of mitochondrial outer membrane for ADP due to interactions of mitochondria with cytoskeleton resulting in quasi-linear dependence of respiration rate on amplitude of cyclic changes in cytoplasmic ADP concentrations. The system of compartmentalized creatine kinase (CK) isoenzymes functionally coupled to ANT and ATPases, and mitochondrial-cytoskeletal interactions separate energy fluxes (mass and energy transfer) from signalling (information transfer) within dissipative metabolic structures – intracellular energetic units (ICEU). Due to the non-equilibrium state of CK reactions, intracellular ATP utilization and mitochondrial ATP regeneration are interconnected by the PCr flux from mitochondria. The feedback regulation of respiration occurring via cyclic fluctuations of cytosolic ADP, Pi and Cr/PCr ensures metabolic stability necessary for normal function of cardiac cells.

Mark R. Pickard and Divya M. Chari
Communication: Robust Uptake of Magnetic Nanoparticles (MNPs) by Central Nervous System (CNS) Microglia: Implications for Particle Uptake in Mixed Neural Cell Populations
Int. J. Mol. Sci. 2010, 11(3), 967-981; doi:10.3390/ijms11030967 - published online 8 March 2010
Show/Hide AbstractAbstract: Magnetic nanoparticles (MNPs) are important contrast agents used to monitor a range of neuropathological processes; microglial cells significantly contribute to MNP uptake in sites of pathology. Microglial activation occurs following most CNS pathologies but it is not known if such activation alters MNP uptake, intracellular processing and toxicity. We assessed these parameters in microglial cultures with and without experimental ‘activation’. Microglia showed rapid and extensive MNP uptake under basal conditions with no changes found following activation; significant microglial toxicity was observed at higher particle concentrations. Based on our findings, we suggest that avid MNP uptake by endogenous CNS microglia could significantly limit uptake by other cellular subtypes in mixed neural cell populations.