oalib

Publish in OALib Journal

ISSN: 2333-9721

APC: Only $99

Submit

Any time

2019 ( 463 )

2018 ( 640 )

2017 ( 651 )

2016 ( 900 )

Custom range...

Search Results: 1 - 10 of 388542 matches for " Lorane I. S. Hage-Melim "
All listed articles are free for downloading (OA Articles)
Page 1 /388542
Display every page Item
Application of Hartree-Fock Method for Modeling of Bioactive Molecules Using SAR and QSPR  [PDF]
Cleydson B. R. Santos, Cleison C. Lobato, Francinaldo S. Braga, Sílvia S. S. Morais, Cesar F. Santos, Caio P. Fernandes, Davi S. B. Brasil, Lorane I. S. Hage-Melim, Williams J. C. Macêdo, José C. T. Carvalho
Computational Molecular Bioscience (CMB) , 2014, DOI: 10.4236/cmb.2014.41001
Abstract:
The central importance of quantum chemistry is to obtain solutions of the Schr?dinger equation for the accurate determination of the properties of atomic and molecular systems that occurred from the calculation of wave functions accurate for many diatomic and polyatomic molecules, using Self Consistent Field method (SCF). The application of quantum chemical methods in the study and planning of bioactive compounds has become a common practice nowadays. From the point of view of planning it is important to note, when it comes to the use of molecular modeling, a collective term that refers to methods and theoretical modeling and computational techniques to mimic the behavior of molecules, not intend to reach a bioactive molecule simply through the use of computer programs. The choice of method for energy minimization depends on factors related to the size of the molecule, parameters of availability, stored data and computational resources. Molecular models generated by the computer are the result of mathematical equations that estimate the positions and properties of the electrons and nuclei, the calculations exploit experimentally, the characteristics of a structure, providing a new perspective on the molecule. In this work we show that studies of Highest Occupied Molecular Orbital Energy (HOMO), Low Unoccupied Molecular Orbital Energy (LUMO) and Map of molecular electrostatic potential (MEP) using Hatree-Fock method with different basis sets (HF/3-21G*, HF/3-21G**, HF/6-31G, HF/6-31G*, HF/6-31G** and HF/6-311G), that are of great importance in modern chemistry, biochemistry, molecular biology, and other fields of knowledge of health sciences. In order to obtain a significant correlation, it is essential that the descriptors are used appropriately. Thus, the quantum chemical calculations are an attractive source of new molecular descriptors that can, in principle, express all the geometrical and electronic properties of molecules and their interactions with biological receptor.
Computational Analysis of Physicochemical, Pharmacokinetic and Toxicological Properties of Deoxyhypusine Synthase Inhibitors with Antimalarial Activity  [PDF]
Nayara S. R. Silva, Luana K. S. Gon?alves, Jonatas L. Duarte, Juliane S. Silva, César F. Santos, Francinaldo S. Braga, Raí C. Silva, Josivan S. Costa, Lorane I. S. Hage-Melim, Cleydson B. R. dos Santos
Computational Molecular Bioscience (CMB) , 2014, DOI: 10.4236/cmb.2014.44006
Abstract: Malaria is a parasitic disease which has as etiological agents protozoa of the genus Plasmodium prevalent in tropical countries. The appearance of Plasmodium strains resistant to artemisinin has become necessary the development of new drugs using computational tools to combat this epidemic. Diverse transporter proteins can act as antimalarials targets, thereby being the enzyme deoxyhypusine synthase a promising antimalarial target. The present study aimed to investigate 15 most active inhibitors of deoxyhypusine synthase target, deposited in databases Binding DB, in order to trace a pattern of physicochemical, pharmacokinetic and toxicological properties of the inhibitors for this enzyme and propose new inhibitors of deoxyhypusine synthase target. The physicochemical properties were obtained according to the Lipinski parameters to evaluate oral absorption. Based on the certain properties were proposed three new inhibitors (A, B and C). The ADME/Tox properties were calculated for new inhibitors compared with results of the selected compounds. The fifteen inhibitors for oral administration showed satisfactory results, because they have adapted to the Lipinski parameters. In relation to the penetration of the blood-brain barrier the inhibitors analyzed showed penetration values less than 1, and ranged from 0.0411815 to 0.481764, being that the compound 1 showed value of CBrain/CBlood = 0.135467. Compound B showed a higher strength in plasma protein binding in relation to the compound 1, having a variation be-tween them of ±1.489344. Therefore, the compound B would present a longer halflife compared with compound 1. The proposed compounds showed positive and satisfactory results, being able to reach less adverse effects related to the central nervous system depending of administered dose.
A SAR and QSAR Study of New Artemisinin Compounds with Antimalarial Activity
Cleydson Breno R. Santos,Josinete B. Vieira,Cleison C. Lobato,Lorane I. S. Hage-Melim,Raimundo N. P. Souto,Clarissa S. Lima,Elizabeth V. M. Costa,Davi S. B. Brasil,Williams Jorge C. Macêdo,José Carlos T. Carvalho
Molecules , 2014, DOI: 10.3390/molecules19010367
Abstract: The Hartree-Fock method and the 6-31G** basis set were employed to calculate the molecular properties of artemisinin and 20 derivatives with antimalarial activity. Maps of molecular electrostatic potential (MEPs) and molecular docking were used to investigate the interaction between ligands and the receptor (heme). Principal component analysis and hierarchical cluster analysis were employed to select the most important descriptors related to activity. The correlation between biological activity and molecular properties was obtained using the partial least squares and principal component regression methods. The regression PLS and PCR models built in this study were also used to predict the antimalarial activity of 30 new artemisinin compounds with unknown activity. The models obtained showed not only statistical significance but also predictive ability. The significant molecular descriptors related to the compounds with antimalarial activity were the hydration energy (HE), the charge on the O11 oxygen atom (QO11), the torsion angle O1-O2-Fe-N2 (D2) and the maximum rate of R/Sanderson Electronegativity (RTe +). These variables led to a physical and structural explanation of the molecular properties that should be selected for when designing new ligands to be used as antimalarial agents.
Nutritional factors in milk from Brazilian mothers delivering small for gestational age neonates
Grumach,Anete S.; Jer?nimo,Solange E.I.; Hage,Marcia; Carneiro-Sampaio,Magda M.S.;
Revista de Saúde Pública , 1993, DOI: 10.1590/S0034-89101993000600008
Abstract: the composition of breast milk from brazilian mothers delivering low birthweight infants and its adequacy as a source of nutrients for this group has not yet been fully elucidated. a total of 209 milk samples from 66 women were analysed. the mothers were divided into three groups: g1, mothers delivering term babies of low birthweight (tsga, n=16); g2, mothers delivering preterm babies of appropriate birthweight (ptaga, n=20); g3, mothers delivering term babies of appropriate birthweight (taga, n=30). the following factors were analysed: osmolarity, total proteins and protein fractions, creamatocrit, sodium, potassium, calcium and magnesium. milk samples were collected 48 h and 7, 15, 30 and 60 days after delivery. the groups did not differ significantly in terms of osmolarity, total proteins and fractions, creamatocrit, calcium, magnesium or potassium throughout the study period. sodium levels were higher in all samples from mothers of tsga infants and in samples from mothers of ptaga infants on the 7th, 15th and 30th days than in milk from the taga group. the authors consider the needs of the low birthweight and taga infants and that these high sodium levels may be necessary for growth of low birthweight infants.
Nutritional factors in milk from Brazilian mothers delivering small for gestational age neonates
Grumach Anete S.,Jer?nimo Solange E.I.,Hage Marcia,Carneiro-Sampaio Magda M.S.
Revista de Saúde Pública , 1993,
Abstract: The composition of breast milk from brazilian mothers delivering low birthweight infants and its adequacy as a source of nutrients for this group has not yet been fully elucidated. A total of 209 milk samples from 66 women were analysed. The mothers were divided into three groups: G1, mothers delivering term babies of low birthweight (TSGA, n=16); G2, mothers delivering preterm babies of appropriate birthweight (PTAGA, n=20); G3, mothers delivering term babies of appropriate birthweight (TAGA, n=30). The following factors were analysed: osmolarity, total proteins and protein fractions, creamatocrit, sodium, potassium, calcium and magnesium. Milk samples were collected 48 h and 7, 15, 30 and 60 days after delivery. The groups did not differ significantly in terms of osmolarity, total proteins and fractions, creamatocrit, calcium, magnesium or potassium throughout the study period. Sodium levels were higher in all samples from mothers of TSGA infants and in samples from mothers of PTAGA infants on the 7th, 15th and 30th days than in milk from the TAGA group. The authors consider the needs of the low birthweight and TAGA infants and that these high sodium levels may be necessary for growth of low birthweight infants.
Espa o portátil: exposi o-publica o
Regina Melim
ARS (S?o Paulo) , 2006, DOI: 10.1590/s1678-53202006000100007
Abstract:
Two new SB2 binaries with main sequence B-type pulsators in the Kepler field
P. I. Pápics,A. Tkachenko,C. Aerts,M. Briquet,P. Marcos-Arenal,P. G. Beck,K. Uytterhoeven,A. Trivi?o Hage,J. Southworth,K. I. Clubb,S. Bloemen,P. Degroote,J. Jackiewicz,J. McKeever,H. Van Winckel,E. Niemczura,J. F. Gameiro,J. Debosscher
Physics , 2013, DOI: 10.1051/0004-6361/201321088
Abstract: Context: OB stars are important in the chemistry and evolution of the Universe, but the sample of targets well understood from an asteroseismological point of view is still too limited to provide feedback on the current evolutionary models. Our study extends this sample with two spectroscopic binary systems. AIMS. Our goal is to provide orbital solutions, fundamental parameters and abundances from disentangled high-resolution high signal-to-noise spectra, as well as to analyse and interpret the variations in the Kepler light curve of these carefully selected targets. This way we continue our efforts to map the instability strips of beta Cep and SPB stars using the combination of high-resolution ground-based spectroscopy and uninterrupted space-based photometry. Methods: We fit Keplerian orbits to radial velocities measured from selected absorption lines of high-resolution spectroscopy using synthetic composite spectra to obtain orbital solutions. We use revised masks to obtain optimal light curves from the original pixel-data from the Kepler satellite, which provided better long term stability compared to the pipeline processed light curves. We use various time-series analysis tools to explore and describe the nature of variations present in the light curve. Results: We find two eccentric double-lined spectroscopic binary systems containing a total of three main sequence B-type stars (and one F-type component) of which at least one in each system exhibits light variations. The light curve analysis (combined with spectroscopy) of the system of two B stars points towards the presence of tidally excited g modes in the primary component. We interpret the variations seen in the second system as classical g mode pulsations driven by the kappa mechanism in the B type primary, and explain the unexpected power in the p mode region as a result of nonlinear resonant mode excitation.
Thyroid Disorders and Diabetes Mellitus
Mirella Hage,Mira S. Zantout,Sami T. Azar
Journal of Thyroid Research , 2011, DOI: 10.4061/2011/439463
Abstract: Studies have found that diabetes and thyroid disorders tend to coexist in patients. Both conditions involve a dysfunction of the endocrine system. Thyroid disorders can have a major impact on glucose control, and untreated thyroid disorders affect the management of diabetes in patients. Consequently, a systematic approach to thyroid testing in patients with diabetes is recommended. 1. Introduction Thyroid diseases and diabetes mellitus are the two most common endocrine disorders encountered in clinical practice. Diabetes and thyroid disorders have been shown to mutually influence each other and associations between both conditions have long been reported [1, 2]. On one hand, thyroid hormones contribute to the regulation of carbohydrate metabolism and pancreatic function, and on the other hand, diabetes affects thyroid function tests to variable extents. This paper demonstrates the importance of recognition of this interdependent relationship between thyroid disease and diabetes which in turn will help guide clinicians on the optimal screening and management of these conditions. 2. Frequency of Thyroid Disorders in the General Population and in Patients with Diabetes Thyroid disorders are widely common with variable prevalence among the different populations. Data from the Whickham survey conducted in the late 1970s in the north of England revealed a prevalence of 6.6% of thyroid dysfunction in the adult general population [3]. In the Colorado Thyroid Disease Prevalence study involving 25,862 participants attending a state health fair, 9.5% of the studied population were found to have an elevated TSH, while 2.2% had a low TSH [4]. In the NHANES III study, a survey of 17,353 subjects representing the US population, hypothyroidism was found in 4.6% and hyperthyroidism in 1.3% of subjects [5]. The latter further observed an increased frequency of thyroid dysfunction with advancing age and a higher prevalence of thyroid disease in women compared to men and in diabetic subjects compared to nondiabetic. Several reports documented a higher than normal prevalence of thyroid dysfunction in the diabetic population. Particularly, Perros et al. demonstrated an overall prevalence of 13.4% of thyroid diseases in diabetics with the highest prevalence in type 1 female diabetics (31.4%) and lowest prevalence in type 2 male diabetics (6.9%) [6]. Recently, a prevalence of 12.3% was reported among Greek diabetic patients [7] and 16% of Saudi patients with type 2 diabetes were found to have thyroid dysfunction [8]. In Jordan, a study reported that thyroid dysfunction was
Determina??o de temperatura de transi??o dúctil-frágil de plásticos através de testes de impacto instrumentado
Correa, Carlos A.;Yamakawa, Roberto S.;Hage Jr., Elias;
Polímeros , 1999, DOI: 10.1590/S0104-14281999000100010
Abstract: the present work intends to point out some of the advantages of using instrumented impact testing over conventional non-instrumented methods in the failure analysis of plastics. in this method, force-displacement diagrams are obtained in "real-time" and used to calculate partial energies of initiation and complete fracture of the specimens. the diagrams yield important information on fracture mechanisms and main characteristics of the failure process. variations of impact energy with temperature can be used in the determination of brittle-ductile transitions or alternatively for evaluation of material susceptibility to stress concentrations, i.e. depth and crack tip radii. the load and energy diagrams were used to illustrate the calculation of the brittle-ductile transition temperature of an acrilonitrile-butadiene-styrene (abs) terpolymer by the new method. analysis of the specimens fractured surfaces by scanning electron microscopy, allowed important correlations between the mode of failure and the main features observed on the load and energy diagrams.
Luto e identifica??o: a propósito de a casa de boneca, de Henrik Ibsen
Hage, Anne;
Psicologia em Estudo , 2005, DOI: 10.1590/S1413-73722005000200015
Abstract: the starting point of our investigation are the passages in h. ibsen "the i and the id" in which freud relates mourning to identification. it aims to discover some aspects of the psychological processes which lead to "the edification of the object in the i" and their consequences such as: how, in which form will the lost object survive in the i? in which way will it participate in the psychological economy? our study takes the h. ibsen drama, a doll's house, as an object. the analyses lead us to articulate and question the identification following a loss regarding notions of narration, temporalness, idealization and debt.
Page 1 /388542
Display every page Item


Home
Copyright © 2008-2017 Open Access Library. All rights reserved.