Total publications: 603
417. Chemometric modeling and pharmacophore mapping in coronary heart disease: 2-arylbenzoxazoles as cholesteryl ester transfer protein inhibitors
in MedChemComm, 2011, ISSN: 2040-2503, Volume: 2,
Article, Indexed in: crossref, scopus
The plasma concentration of HDL-C and the prevalence of coronary heart disease (CHD) is inversely related. Inhibition of cholesteryl ester transfer protein (CETP) is considered to be a potential approach to treat dyslipidemia and CHD. 2-arylbenzoxazoles were found to be a potential class of CETP inhibitors. A 2D QSAR study was done on a series of 2-arylbenzoxazoles using PCR, PLS and MLR techniques and externally validated to determine significant models. kNN-MFA 3D QSAR was performed on the same series to correlate the effects of electrostatic, steric and hydrophobic parameters with the CETP inhibitory activity using forward backward regression, genetic algorithm and simulated annealing methods. Pharmacophore mapping was also done on the conformers of the 2-arylbenzoxazoles generated by the BEST and the FAST method. This work may provide a platform for generating leads for novel CETP inhibitors. © 2011 The Royal Society of Chemistry.
418. Current Computational Approaches Towards the Rational Design of New Insecticidal Agents
in CURRENT COMPUTER-AIDED DRUG DESIGN, 2011, ISSN: 1573-4099, Volume: 7,
Article, Indexed in: scopus, wos
Pesticides are chemicals with a great impact in the economy of any country. They are employed for the eradication of pests. Insects constitute one of these pests which are extremely difficult to control. With the passage of the time, insects have become resistant to pesticides, causing huge crop losses and diseases in humans. For this reason, there is an increasing need for the design of more potent insecticides. The present review is focused on the current state of the application of computational approaches as essential tools for the design of novel insecticidal agents. Also, a model based on a substructural approach is presented as a rational, efficient and promising alternative for the discovery of new insecticides.
419. Current Drug Design of Anti-HIV Agents Through the Inhibition of C-C Chemokine Receptor Type 5
in CURRENT COMPUTER-AIDED DRUG DESIGN, 2011, ISSN: 1573-4099, Volume: 7,
Article, Indexed in: scopus, wos
Human immunodeficiency virus (HIV) is the responsible causal agent of acquired immunodeficiency syndrome (AIDS), a condition in humans in which the immune system begins to fail, allowing the entry of opportunistic infections. HIV infection in humans is considered pandemic by the World Health Organization (WHO). HIV needs to use a protein as a co-receptor to enter its target cells. Several chemokine receptors can in principle act as viral co-receptors, but the chemokine (C-C motif) receptor 5 (CCR5) is likely the most physiologically important co-receptor during natural infection. For this reason the development of new CCR5 inhibitors like anti-HIV agents, constitutes a challenge for the scientific community. The present review will focus on the current state of the design of novel anti-HIV drugs, and how the existing computer aided-drug design methodologies, have been effective in the search of new anti-HIV agents. In addition, a QSAR model based on substructural descirptors is presented as a rapid, rational and promising alternative for the discovery of anti-HIV agents through the inhibition of the CCR5.
420. DFT study on the NO oxidation on a flat gold surface model
in CHEMICAL PHYSICS LETTERS, 2011, ISSN: 0009-2614, Volume: 503,
Article, Indexed in: crossref, scopus, wos
The reaction of NO oxidation on Au(1 1 1), either with atomic or molecular oxygen, was studied by means of density functional theory. The oxidation of NO by atomic oxygen is exothermic, it occurs without activation energy barrier but is limited by the energy required to desorb NO(2) from the surface (0.78 eV). For NO oxidation with molecular oxygen, two different exothermic reaction routes were analyzed. In one case, the release of gaseous NO(2) is limited by pre-adsorption of molecular oxygen on the surface while, in the other, the reaction is facile but the barrier for NO(2) desorption needs to be surpassed.
421. Effects of Coagulase-Negative Staphylococci and Fibrin on Breast Capsule Formation in a Rabbit Model
in AESTHETIC SURGERY JOURNAL, 2011, ISSN: 1090-820X, Volume: 31,
Article, Indexed in: crossref, scopus, wos
Background: The etiology and ideal clinical treatment of capsular contracture (CC) remain unresolved. Bacteria, especially coagulase-negative staphylococci, have been previously shown to accelerate the onset of CC. The role of fibrin in capsule formation has also been controversial. Objective: The authors investigate whether fibrin and coagulase-negative staphylococci (CoNS) modulate the histological, microbiological, and clinical outcomes of breast implant capsule formation in a rabbit model and evaluate contamination during the surgical procedure. Methods: Thirty-one New Zealand white female rabbits were each implanted with one tissue expander and two breast implants. The rabbits received (1) untreated implants and expanders (control; n = 10), (2) two implants sprayed with 2 mL of fibrin and one expander sprayed with 0.5 mL of fibrin (fibrin; n = 11), or (3) two implants inoculated with 100 mu L of a CoNS suspension (10(8)CFU/mL-0.5 density on the McFarland scale) and one expander inoculated with a CoNS suspension of 2.5 x 10(7) CFU/mL (CoNS; n = 10). Pressure/volume curves and histological and microbiological evaluations were performed. Operating room air samples and contact skin samples were collected for microbiological evaluation. The rabbits were euthanized at four weeks. Results: In the fibrin group, significantly decreased intracapsular pressures, thinner capsules, loose/dense (<25%) connective tissue, and negative/mild angiogenesis were observed. In the CoNS group, increased capsular thicknesses and polymorph-type inflammatory cells were the most common findings. Similar bacteria in capsules, implants, and skin were cultured from all the study groups. One Baker grade IV contracture was observed in an implant infected with Micrococcus spp. Conclusions: Fibrin was associated with reduced capsule formation in this preclinical animal model, which makes fibrin an attractive potential therapeutic agent in women undergoing breast augmentation procedures. Clinical strategies for preventing bacterial contamination during surgery are crucial, as low pathogenic agents may promote CC.
422. Effects of Fibrin, Thrombin, and Blood on Breast Capsule Formation in a Preclinical Model
in AESTHETIC SURGERY JOURNAL, 2011, ISSN: 1090-820X, Volume: 31,
Article, Indexed in: crossref, scopus, wos
Background: The root cause of capsular contracture (CC) associated with breast implants is unknown. Recent evidence points to the possible role of fibrin and bacteria in CC formation. Objectives: The authors sought to determine whether fibrin, thrombin, and blood modulated the histological and microbiological outcomes of breast implant capsule formation in a rabbit model. Methods: The authors carried out a case-control study to assess the influence of fibrin, thrombin, and blood on capsule wound healing in a rabbit model. Eighteen New Zealand white rabbits received four tissue expanders. One expander acted as a control, whereas the other expander pockets received one of the following: fibrin glue, rabbit blood, or thrombin sealant. Intracapsular pressure/volume curves were compared among the groups, and histological and microbiological evaluations were performed (capsules, tissue expanders, rabbit skin, and air). The rabbits were euthanized at two or four weeks. Results: At four weeks, the fibrin and thrombin expanders demonstrated significantly decreased intracapsular pressure compared to the control group. In the control and fibrin groups, mixed inflammation correlated with decreased intracapsular pressure, whereas mononuclear inflammation correlated with increased intracapsular pressure. The predominant isolate in the capsules, tissue expanders, and rabbit skin was coagulase-negative staphylococci. For fibrin and thrombin, both cultures that showed an organism other than staphylococci and cultures that were negative were associated with decreased intracapsular pressure, whereas cultures positive for staphylococci were associated with increased intracapsular pressure. Conclusions: Fibrin application during breast implantation may reduce rates of CC, but the presence of staphylococci is associated with increased capsule pressure even in the presence of fibrin, so care should be taken to avoid bacterial contamination.
423. Fragment-based QSAR model toward the selection of versatile anti-sarcoma leads
in EUROPEAN JOURNAL OF MEDICINAL CHEMISTRY, 2011, ISSN: 0223-5234, Volume: 46,
Article, Indexed in: crossref, scopus, wos
A sarcoma is a type of cancer which is originated from the connective tissue cells. With the time, several sarcomas have become resistant to the current anti-tumoral drugs. Many works have been reported in order to explain some mechanisms of resistance in different types of sarcomas and around 2000 compounds have been tested as anti-sarcoma agents against several sarcoma cell lines. However, there is no an available methodology for the rational design of compounds with anti-sarcoma activity. The present work develops a unified fragment-based approach by employing a multi-target QSAR model for the efficient search and design of new anti-sarcoma agents against 12 sarcoma cell lines. The model was obtained with the use of a heterogeneous database of compounds and it was based on substructural descriptors. The percentages of correct classification of active and inactive compounds were higher than 85% in both cases. Also, the present approach provided the rapid extraction of substructural alerts responsible of anti-sarcoma profile by calculating the quantitative contributions of fragments to anti-sarcoma activity. To our knowledge, this is the first attempt to calculate the probabilities of anti-sarcoma activity of compounds against several sarcoma cell lines simultaneously, using a unified fragment-based QSAR model.
424. Hydration Structure of Cocaine and its Metabolites: A Molecular Dynamics Study
in JOURNAL OF SOLUTION CHEMISTRY, 2011, ISSN: 0095-9782, Volume: 40,
Article, Indexed in: crossref, scopus, wos
We present molecular dynamics simulations of solvated cocaine and its metabolites in water, using both the Optimized Potentials for Liquid Simulations (OPLS) force field and the same force field but with Quantum Theory of Atoms In Molecules (QTAIM) atomic charges. We focus on the microscopic aspects of solvation, e.g. hydrogen bonds, and investigate influence of partial charges applied. Hydrophobicity or hydrophicility of these molecules were analyzed in terms of solute-solvent radial distribution functions and, for their most hydrophilic atoms, by spatial density functions. These hydration studies allowed us to classify these molecules according to their total coordination numbers, from the most hydrated metabolite to least hydrated, and this trend matches the degree of each metabolite is excreted in urine of patients with a high consumption of cocaine. Finally, we observed that QTAIM charges provide a more physically reasonable description of electrostatic environment of these solvated molecules than those of OPLS charges.