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Issue 1, Volume 6,
January 2009
Title
of the Paper: Nonlinear Evolutionary Process in Biophysics: An Hamiltonian
Representation
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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
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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
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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)
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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
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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
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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
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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
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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
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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
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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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