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 Volume 6,  2009
Print ISSN: 1109-9518
E-ISSN: 2224-2902








Issue 1, Volume 6, January 2009

Title of the Paper: Nonlinear Evolutionary Process in Biophysics: An Hamiltonian Representation


Authors: J. Quartieri, S. Steri, N. E. Mastorakis, C. Guarnaccia

Abstract: The behaviour of a cellular colony in controlled growth is here exploited by means of new mathematical models. The first aim of the paper is to introduce the Hamiltonian function in an analytic nonlinear evolutionary process. In analogy with the finite optimal processes theory, this study leads to the introduction of a canonical representation of the process by means of two sequences of equations. This means that one has to introduce “adjoint variables”, namely “generalized momenta”, which play the role of classical momenta and have to be considered together with the “positional variables”. A correct explanation of the physical meaning of these new variables gives the possibility to extend the analogy with classical mechanics. In this scenario, a biological problem can be considered and used as a case study for this analogy. The authors have already studied the controlled evolution of a cellular colony in some recent papers. Now the application of an Hamiltonian representation to the stochastic process of a tumoral cells colony is approached by means of the introduction of the canonical variables. This hopefully could lead to the begin of a new optimal control of drug therapy in the evolution of a tumoral colony.

Keywords: Hamiltonian Function, Optimal Control, Cellular Colony

Title of the Paper: Data Warehouse and the Deployment of Data Mining Process To Make Decision for Leishmaniasis and Development of Mathematical Models for Phlebotomine Sandflies Seasonality in Marrakech City


Authors: Habiba Mejhed, Samia Boussaa, Nour El Houda Mejhed

Abstract: This proposal is based on the implementation and the development of tools to analyze the decision making indicators in the epidemiology for the ministry of the health. First, we introduced new tools of data warehouse and data mining to improve epidemiological knowledge specific to the Leishmaniasis in south of Morocco. We developed an information system to facilitate the decision-making process, access to the information and data storage in the data warehouse. We considered the density of the sandflies population when taking into account the time and climate change. We are interested in patients with suspected Leishmania infection, so we included the transmission of Leishmaniasis to humans. The concept of Data mining is used to select, to explore and to transform our epidemic data to a prediction index. In order to reduce the transmission of leishmaniasis and to control the vector density, we also suggest developing a simple mathematical model with entomological data in Marrakech area. This model predicts the vector density according to local conditions. Simulations have been done on actual data collected in Marrakesh city to confirm the leishmaniasis risk in this area. In this paper we review the type of decision aids which has been successfully implemented and that we have provided to the responsible of the population health to make better decisions.

Keywords: Epidemiology, Information system, Database, Decision support, Data warehouse, Mathematical model, Morocco

Issue 2, Volume 6, April 2009

Title of the Paper: A Prebiotic Surface Catalysed Synthesis of Alkyl Imine Precursors to the Aminoacids, Alanine, Serine and Threonine


Authors: Nigel Aylward

Abstract: Alkynes such as ethyne and propyne form weak charge-transfer, ?2 -alkynyl complexes with surface catalysts such as Mg.porphin in which the alkynyl group is positively charged and the porphin has a negative charge. The enthalpy changes are -0.018 and -0.002 h, respectively. Addition of ammonia to the complexes allows the formation of Mg.2-amino ethenyl.porphin and Mg.2-amino propenyl.porphin with small enthalpy changes. and subsequent cyclic formation to Mg.1H aziridin-2yl.porphin and Mg. 2-methyl 1H aziridin-3yl.porphin complexes. The former may undergo a prototropic ring opening to form the imino precursor to the amino-acid alanine. Both complexes undergo ring opening with hydroxide anion to give the imine precursors to the amino-acids, serine and threonine. where the activation energies and enthalpy changes are,respectively, 0.072 h and -0.159h, and 0.072 h and -0.167 h. This mechanism constitutes another method for the formation of reactive, and unstable, imines that could facilitate the formation of aziridine-2ones, which have been predicated as important in amino acid synthesis. The reactions have been shown to be feasible from the overall enthalpy changes in the ZKE approximation at the HF and MP2 /6-31G* level.

Keywords: Alkynes, 2-amino ethenyl, 2-amino propenyl, 1H aziridin-2yl and 1H 2-methyl aziridin-3yl complexes of Mg.porphin

Title of the Paper: The Reestablishment of American Ginseng (Panax Quinquefolius)


Authors: Mary Snow, Richard Snow

Abstract: Conservation biology and restoration ecology are concerned not only with protecting fragile ecosystems but also with intervening in an attempt to repair what has been damaged largely through anthropogenic activities. As a result of high demand as a medicinal herb and the failure of harvesters to conserve, the federal government has placed American ginseng (Panax quinquefolius) on the list of plants that may be in danger of extinction. Ginseng favors a habitat ranging from 30 to 50 degrees north latitude and minimum cold cycles of 45 days with temperatures below 2 degrees Celsius. Other specific criteria include 20 inches of annual precipitation, adequate shade, and slightly acidic, well-drained soil that is high in organic material content. Remote sensing, ground truthing, and an analysis of local climate data helped determine whether the study areas met these requirements. The role of remote sensing and the use of GIS in preserving forests and biodiversity are discussed. Although it could take from eight to ten years before harvest, the wild simulated ginseng roots command a price that is approximately the same as that of wild ginseng. The present body of knowledge concerning the optimal growing conditions of ginseng should be enhanced as a result of this research and could serve as a model for a viable economic alternative to clear cutting deciduous forests, which is among the long term goals of this project.

Keywords: Conservation biology, Restoration ecology, Endangered species, American Ginseng, Remote sensing, GIS

Issue 3, Volume 6, July 2009

Title of the Paper: A Method for Subject Specific Estimation of Aortic Wall Shear Stress


Authors: Johan Renner, Roland Gardhagen, Tino Ebbers, Einar Heiberg, Toste Lanne, Matts Karlsson

Abstract: Wall shear stress (WSS) distribution in the human aorta is a highly interesting hemodynamic factor for atherosclerosis development. We present a magnetic resonance imaging (MRI) and computational fluid dynamics (CFD) based subject specific WSS estimation method and demonstrate it on a group of nine healthy volunteers (males age 23.6 ± 1.3 years). In all nine subjects, the aortic blood flow was simulated in a subject specific way, where the 3D segmented geometries and inflow profiles were obtained using MRI. No parameter settings were tailored using data from the nine subjects. Validation was performed by comparing CFD gained velocity with magnetic resonance imaging (MRI) velocity measurements. CFD and MRI velocity profiles were comparable, but the temporal variations of the differences during the cardiac cycle were significant. Spatio-temporal analyzes on the WSS distribution showed a strong subject specific influence. Subject specific models are decisive to estimate WSS distribution.

Keywords: WSS, Aorta, Subject Specific, MRI, CFD, Velocity Validation, 3D segmentation

Title of the Paper: New Aspects of the Relationship between Acetylcholinesterase Activity and Cancer I: Poly-Aps Experiments


Authors: Zovko A., Sepcic K., Turk T., Faimali M., Garaventa F.,Chelossi E., Paleari L., Falugi C., Aluigi M.G., Angelini C., Trombino S., Gallus L., Ferrando S.

Abstract: Since the first ‘80s, we found that some tumor types, and in particular lung tumors present increase, or generally change in acetylcholinesterase activity. Acetylcholinesterase is an enzyme associated to the cholinergic signal system, whose classic role is to remove acetylcholine from the receptors. Nevertheless, it is also involved in cell-to-cell communication driving embryonic development and in the regulation of several cellular features, such as apoptosis and cell movements. The presence of molecules related to the cholinergic signal system in the healthy and carcinogenic lung tissues, raised the hypothesis that substances inhibiting or affecting the cholinergic signaling system could exert an anticancer action at least in these tissues. Cytotoxicity tests on immortalized and primary cell lines derived from lung tumor (NSCLC) showed an AChE inhibition-dependent selective reduction of cell viability, statistically significant. The same cells, exposed to non toxic AChE inhibitors exhibited a loss in the mitochondrial potential, characteristic of the early apoptotic events and showed positive response to the annexin V assay, and to the T-terminal assay, that are specific features of the apoptotic event. Moreover, three-dimensional cell cultures (spheroids) of tumor cells, on exposure to AChE inhibitors show a decrease in the membrane-linked oligosaccharides, that are responsible for the adhesivity of the metastatic cells. In this promising picture, the need emerges of further studies aimed at understanding the effects of AChE inhibition on the regulation of acetylcholine release and the effects of AChE inhibitors on the functioning of acetylcholine receptors.

Keywords: Anti-cancer, natural drug, lung cancer, acetylcholinesterase, apoptosis, cell proliferation, Reniera sarai sponge

Title of the Paper: Dental Treatment Considerations for the Organ and Bone Marrow Transplant Patient


Authors: Corina-Mona Buzea, Marian Cuculescu, Elena Podoleanu, Cristina Teodora Preoteasa, Roxana Ranga

Abstract: Organ and bone marrow transplant represents a chance to life for the patients with end-stage diseases like terminal cardiac, hepatic, renal failure or leukemia, aplastic anemia and immune deficiency syndromes. The success of the transplantation procedure depends on the immune reactivity of the recipient patient, which may trigger the rejection or reject phenomena. The immunosuppressive drugs, administrated in the posttransplant phase have the role of preventing rejection, but they have also side effects, with implications throughout the body, including the oral cavity. The aim of this paper is to make the dentist aware of the particularities and special needs of organ and bone marrow transplant patients, in the context of the general medical aspects, the specific medication and the necessity of an effective dental treatment, which can play an important part in these patients' lives.

Keywords: Organ transplant, bone marrow transplant, dental treatment considerations

Issue 4, Volume 6, October 2009

Title of the Paper: Ab Initio Study of Nodifloridin-A and Nodifloridin-B in Vacuo and in Solution


Authors: Liliana Mammino, Mwadham M. Kabanda

Abstract: Nodifloridin-A and nodifloridin-B are naturally occurring compounds with similar biological activities. Their molecular structures have similar substituents on a phenol moiety for nodifloridin-A and on a phloroglucinol moiety for nodifloridin-B. An ab initio conformational study in vacuo and in three solvents with different polarities (chloroform, acetonitrile and water) highlights a determining influence of the hydroxybenzene moiety on conformational preferences and energies, largely related to the moiety’s number of hydrogen bond donor/acceptor sites. Intramolecular hydrogen bonding is given particular attention in view of its role in influencing conformational preferences and energies and its possible roles in the biological activity.

Keywords: 1,3,5-Trihydroxybenzene, Acetonitrile solutions, Acylphloroglucinols, Chloroform solutions, Intramolecular Hydrogen Bonding, Nodifloridin, Phenolic derivatives, Solute-Solvent Interactions, Water solutions.

Title of the Paper: Conformational Effects of the Valine Side Chain on the Extended in the HCO-Gly-L-Val-Gly-NH2 Tripeptide Motif: An Ab Initio and DFT Exploratory Study


Authors: Behzad Chahkandi , Badrosadat Seyed Hosseini

Abstract: Ab initio and DFT molecular computations were carried out on the HCO-Gly-L-Val-Gly-NH2 tripeptide at the HF/6-31G(d) and B3LYP/6-31G(d) levels of theory. The study of conformation in HCO-Gly-L-Val-Gly-NH2 tripeptide, which is in repeating sequences of parent elastin-mimetic polypeptide, were performed with varying of side chain torsional angle (χ) and backbone dihedral angles ( Φ2,Ψ2 ), to finding the most stable conformer. At first the side chain torsional angle (χ) as a variable of the energy function was changed at 30° intervals from 0° to 360°. Three minima, gauche (-) , gauche (+) and anti, were obtained that among of them, gauche (-) conformer has the lowest energy. Afterward the two terminal glycine moieties were kept in the conformations while the conformation of the central valine was varied for three states, gauche (-), anti and gauche (+). In addition to electronic energy (E), the key thermodynamic functions: enthalpy (H), Gibbs free energy (G) and entropy (S) were obtained at B3LYP/6-31G(d) level of theory. The most stable conformation for three states of valine , gauche (+), anti and gauche (-) is βLβLβL conformation and also in gauche (+), anti and gauche (-) states 8, 7 and 6 conformers were found respectively. The obtained , , and βLαDβL Conformations in this three states, are more stable in anti state than other two states. According to obtained results dipole-dipole attraction interactions and also entropy play the main role in forming a more stable conformer.

Keywords: B3LYP, Conformational analysis, Elastine, HF, HCO-Gly-L-Val-Gly-NH2, Ramachandran

Title of the Paper: Investigation of Tautomeric Equilibria of 6-Hydroxy-5-Flourocytosine and the Effect of Temperature on some Equilibria


Authors: Behzasd Chahkandi, Sorour Hasani

Abstract: Optimal molecular geometries and molecular energies were obtained for 6-Hydroxy-5- Flucytosine(OHFC) , one of the important and new metabolites of Flucytosine,an antifungal agents, with the use of the theoretical ab initio and DFT quantum mechanical calculations .The 6-31G* and 6-31G** Gussian basis sets were employed. 17 possible tautomeric forms were considered. And also thermodynamic properties (??? ??????? for tautomeric equilibria between different tautomers were calculated with the frequency calculations. For all calculations levels, OHFC14 form appeared to be the most stable form and it’s energy is -569.406642 at the highest level and OHFC6 form is by 47.76 kcal mol-1 less stable than OHFC14.In any case ,30 tautomeric equilibria were considered between17 tautomers.Considering of tautomeric equilibria defines that equilibrium OHFC2 OHFC5(T7) is the most stable equilibrium and it’s is -26.750102 Kcal/mol .We classified these equilibria according (CN,CO,NN,NO) structural models .The effect of temperature on the stability of CO models equilibria have been investigated through the DFT level. Changes of free energy and enthalpy were obtained. We continued our investigation on heat capacity at constant pressure (CP) and equilibrium constant (Keq). It was found that in endothermic reactions, increasing in temperature causes increasing in Keq. In exothermic reactions, increasing in temperature causes decreasing in Keq. And also it was appeared that the values of CP for all tautomers were increased with temperature.

Keywords: Tautomerism, 6-Hydroxy-5-Flucytosine,Nucleotid bases,antifungul,mutation, exothermic, endothermic

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