Energetics and solvation structure of a dihalogen dopant (I2) in (4)He clusters.

The energetics and structure of small HeNI2 clusters are analyzed as the size of the system changes, with N up to 38. The full interaction between the I2 molecule and the He atoms is based on analytical ab initio He-I2 potentials plus the He-He interaction, obtained from first-principle calculations. The most stable structures, as a function of the number of solvent He atoms, are obtained by employing an evolutionary algorithm and compared with CCSD(T) and MP2 ab initio computations.

Full-dimensional quantum calculations of the dissociation energy, zero-point, and 10 K properties of H7+/D7+ clusters using an ab initio potential energy surface.

Diffusion Monte Carlo (DMC) and path-integral Monte Carlo computations of the vibrational ground state and 10 K equilibrium state properties of the H7 (+)/D7 (+) cations are presented, using an ab initio full-dimensional potential energy surface. The DMC zero-point energies of dissociated fragments H5 (+)(D5 (+))+H2(D2) are also calculated and from these results and the electronic dissociation energy, dissociation energies, D0, of 752 ± 15 and 980 ± 14 cm(-1) are reported for H7 (+) and D7 (+), respectively. Due to the known error in the electronic dissociation energy of the potential surface, these quantities are underestimated by roughly 65 cm(-1).

Full-dimensional (15-dimensional) ab initio analytical potential energy surface for the H7+ cluster.

Full-dimensional ab initio potential energy surface is constructed for the H(7)(+) cluster. The surface is a fit to roughly 160,000 interaction energies obtained with second-order MöllerPlesset perturbation theory and the cc-pVQZ basis set, using the invariant polynomial method [B. J.

Changes in body composition and mitochondrial DNA in HIV-1-infected patients switching to fixed-dose abacavir/lamivudine or tenofovir/emtricitabine: a substudy of the BICOMBO trial.

Background: Fat distribution, bone mineral density (BMD) and mitochondrial DNA (mtDNA) may improve, in the long-term, after switching from nucleoside reverse transcriptase inhibitors (NRTIs) to fixed-dose abacavir (ABC)/lamivudine (3TC) or tenofovir (TDF)/emtricitabine (FTC).

Methods: This was a prospective, randomized, open-label, multicentre substudy of the BICOMBO trial in which virologically suppressed patients had their NRTIs switched to ABC/3TC or TDF/FTC. Whole-body dual-energy X-ray absorptiometry (DXA) was used to measure limb, trunk and total body fat and total BMD.

Low-density lipoprotein size and lipoprotein-associated phospholipase A2 in HIV-infected patients switching to abacavir or tenofovir.

Background: The aim of this study was to assess changes in the size and cholesterol content of low-density lipoproteins (LDL) and changes in lipoprotein-associated phospholipase A2 (Lp-PLA2) activity in HIV-infected patients switching to tenofovir + emtricitabine (TDF+FTC) or abacavir + lamivudine (ABC+3TC).

Methods: This was a substudy of a multicentre randomized trial comparing TDF+FTC with ABC+3TC-based regimens in patients with virological suppression. Fasting lipids and apolipoproteins (apo), LDL size and cholesterol content and Lp-PLA2 activity were measured at baseline and at week 48.

Internal proton transfer and H2 rotations in the H5(+) cluster: a marked influence on its thermal equilibrium state.

Classical and path integral Monte Carlo (CMC, PIMC) "on the fly" calculations are carried out to investigate anharmonic quantum effects on the thermal equilibrium structure of the H5(+) cluster. The idea to follow in our computations is based on using a combination of the above-mentioned nuclear classical and quantum statistical methods, and first-principles density functional (DFT) electronic structure calculations. The interaction energies are computed within the DFT framework using the B3(H) hybrid functional, specially designed for hydrogen-only systems.

Community associated methicillin-resistant Staphylococcus aureus in HIV-infected patients.

Until recently, methicillin-resistant Staphylococcus aureus was considered an uncommon community pathogen, almost exclusively associated with healthcare exposure. Over the last decade, however, methicillin-resistant S. aureus infection, particularly skin and soft tissue infection, has emerged in healthy individuals with no traditional risk factors for its acquisition.

Toward a realistic density functional theory potential energy surface for the H5+ cluster.

The potential energy surface of H(5)(+) is characterized using density functional theory. The hypersurface is evaluated at selected configurations employing different functionals, and compared with results obtained from ab initio CCSD(T) calculations. The lowest ten stationary points (minima and saddle-points) on the surface are located, and the features of the short-, intermediate-, and long-range intermolecular interactions are also investigated.

Visceral Leishmaniasis treated with antimonials/paromomycin followed by itraconazole/miltefosine after standard therapy failures in a human immunodeficiency virus-infected patient.

Visceral leishmaniasis is an opportunistic infection that affects human immunodeficiency virus-infected persons in leishmaniasis-endemic areas. The standard treatment may not be effective and relapses are common. We report the case of a human immunodeficiency virus-1-infected patient who had several relapses of visceral leishmaniasis after treatment with standard therapies and responded to a combined therapy.

Abacavir-based therapy does not affect biological mechanisms associated with cardiovascular dysfunction.

Objective: To assess the effects of initiating abacavir-containing therapy on plasma lipids and cardiovascular biomarkers.

Design: Sub-study of the BICOMBO study in which participants were randomized to switch their nucleoside backbone to either abacavir/lamivudine or tenofovir/emtricitabine.

Methods: We assessed 48-week changes in fasting lipids and several biomarkers including serum high-sensitivity C-reactive protein (hsCRP), monocyte chemoattractant protein-1 (MCP-1), osteoprotegerin, interleukin (IL)-6, IL-10, tumor necrosis factor alpha (TNF-alpha), intercellular adhesion molecule-1 (ICAM-1), vascular adhesion molecule-1 (VCAM-1), selectin E and P, adiponectin, insulin, and D-dimer in otherwise healthy, virologically suppressed HIV-infected patients randomly switched to abacavir/lamivudine or tenofovir/emtricitabine with no history of cardiovascular disease, no prior abacavir or tenofovir use, and no virological failure or AIDS during follow-up.

A simplification trial switching from nucleoside reverse transcriptase inhibitors to once-daily fixed-dose abacavir/lamivudine or tenofovir/emtricitabine in HIV-1-infected patients with virological suppression.

Background: Data comparing abacavir/lamivudine versus tenofovir/emtricitabine in antiretroviral-naive patients are controversial. We compared 48-week efficacy and safety of these combinations as substitutes of nucleosides in patients with virological suppression.

Methods: We randomly assigned 333 HIV-1-infected patients on lamivudine-containing triple regimens with <200 copies per milliliter for at least 6 months to switch their nucleosides to either abacavir/lamivudine (n = 167) or tenofovir/emtricitabine (n = 166).

Lopinavir/ritonavir: a protease inhibitor for HIV-1 treatment.

Background: Lopinavir is a protease inhibitor with high specificity for HIV-1 protease formulated with ritonavir. Numerous clinical trials have shown that lopinavir/ritonavir (LPV/r) is highly effective as a component of highly active antiretroviral therapy (HAART) regimens for HIV-1 infection.

Objective: In this article we provide an overview of the properties of LPV/r and the experience with its use in HIV-infected adults and adolescents.

Switching strategies to improve lipid profile and morphologic changes.

Metabolic alterations and body fat changes are well-recognized limitations of protease inhibitor-based regimens. Strategies of replacing protease inhibitors with nonnucleoside reverse transcriptase inhibitors or abacavir have been shown to improve metabolic abnormalities, particularly by decreasing cholesterol and triglyceride levels, and reducing cardiovascular risk. The various therapeutic options show differences in efficacy, tolerability, and metabolic outcomes.