Incidence of HIV-1 drug resistance among antiretroviral treatment-naive individuals starting modern therapy combinations.

BACKGROUND: Estimates of drug resistance incidence to modern first-line combination antiretroviral therapies against human immunodeficiency virus (HIV) type 1 are complicated by limited availability of genotypic drug resistance tests (GRTs) and uncertain timing of resistance emergence. METHODS: Five first-line combinations were studied (all paired with lamivudine or emtricitabine): efavirenz (EFV) plus zidovudine (AZT) (n = 524); EFV plus tenofovir (TDF) (n = 615); lopinavir (LPV) plus AZT (n = 573); LPV plus TDF (n = 301); and ritonavir-boosted atazanavir (ATZ/r) plus TDF (n = 250). Virological treatment outcomes were classified into 3 risk strata for emergence of resistance, based on whether undetectable HIV RNA levels were maintained during therapy and, if not, whether viral loads were >500 copies/mL during treatment. Probabilities for presence of resistance mutations were estimated from GRTs (n = 2876) according to risk stratum and therapy received at time of testing. On the basis of these data, events of resistance emergence were imputed for each individual and were assessed using survival analysis. Imputation was repeated 100 times, and results were summarized by median values (2.5th-97.5th percentile range). RESULTS: Six years after treatment initiation, EFV plus AZT showed the highest cumulative resistance incidence (16%) of all regimens (<11%). Confounder-adjusted Cox regression confirmed that first-line EFV plus AZT (reference) was associated with a higher median hazard for resistance emergence, compared with other treatments: EFV plus TDF (hazard ratio [HR], 0.57; range, 0.42-0.76), LPV plus AZT (HR, 0.63; range, 0.45-0.89), LPV plus TDF (HR, 0.55; range, 0.33-0.83), ATZ/r plus TDF (HR, 0.43; range, 0.17-0.83). Two-thirds of resistance events were associated with detectable HIV RNA level ≤500 copies/mL during treatment, and only one-third with virological failure (HIV RNA level, >500 copies/mL). CONCLUSIONS: The inclusion of TDF instead of AZT and ATZ/r was correlated with lower rates of resistance emergence, most likely because of improved tolerability and pharmacokinetics resulting from a once-daily dosage.

Inferring about individual drug and schizotypy effects on cognitive functioning in polydrug using mephedrone users before and after clubbing

Objective: Mephedrone has been recently made illegal in Europe, but little empirical evidence is available on its impact on human cognitive functions. We investigated acute and chronic effects of mephedrone consumption on drug-sensitive cognitive measures, while also accounting for the influence of associated additional drug use and personality features. Method: Twenty-six volunteers from the general population performed tasks measuring verbal learning, verbal fluency and cognitive flexibility before and after a potential drug-taking situation (pre- and post-clubbing at dance clubs, respectively). Participants also provided information on chronic and recent drug use, schizotypal (O-LIFE) and depressive symptoms (Beck depression inventory), sleep pattern and premorbid IQ. Results: We found that i) mephedrone users performed worse than non-users pre-clubbing, and deteriorated from the pre-clubbing to the post-clubbing assessment, ii) pre-clubbing cannabis and amphetamine (not mephedrone) use predicted relative cognitive attenuations, iii) post-clubbing, depression scores predicted relative cognitive attenuations, and iv) schizotypy was largely unrelated to cognitive functioning, apart from a negative relationship between cognitive disorganisation and verbal fluency. Conclusion: Results suggest that polydrug use and depressive symptoms in the general population negatively affect cognition. For schizotypy, only elevated cognitive disorganisation showed potential links to a pathological cognitive profile previously reported along the psychosis dimension.

Malignant pleural mesothelioma: leukocyte recruitment is not required for drug delivery induced by photodynamic therapy in a human xenograft model

Objective: The pre-treatment of tumor neo-vessels by photodynamic therapy (PDT) was shown to improve the distribution of chemotherapy administered subsequently. However, the precise mechanism by which PDT modifies the tumor vasculature is unknown. We have recently shown that leukocyteendothelial cell interaction was essential for PDT induced drug delivery to normal tissue. Our purpose was to determine if PDT could enhance drug distribution in malignant mesothelioma and if a comparable role for leucocytes existed.Methods: We grew human mesothelioma xenografts (H-meso-1) in the dorsal skinfold chambers of nude mice (n = 28). The rolling, sticking and recruitment of leucocytes was assessed in tumor and normal vessels following PDT (Visudyne 0?4 mg/kg, fluence rate 200 mW/cm2, fluence 60 J/cm2) using intravital microscopy. In parallel, the distribution of a macromolecule (FITC dextran, 2000 kDa) administered after PDT was determined. We compared these variables in control (no PDT), PDT + IgG (non specific antibody) and PDT + pan-selectin antibody (monoclonal P-E-L selectin antibody).Results: PDT significantly enhanced the distribution of FITC dextran in mesothelioma xenografts compared to controls. Interestingly, PDT enhanced the leukocyte-endothelial interaction significantly (rolling and recruitment)in tumor and surrounding normal vessels compared to controls. Leukocyte recruitment was significantly down-regulated by pan-selectin antibodies in tumor tissues. However, the suppression of leucocyte recruitement did not affect the extravasation of FITC-dextran in tumor tissue.Conclusion:PDTpre-treatment of the mesothelioma vasculature can enhance the distribution of macromolecular drugs administered subsequently. However, unlike normal vessels, leukocyte-endothelial cell interaction is not required for PDT induced leakage.

Shotgun Ecotoxicoproteomics of Daphnia pulex: Biochemical Effects of the Anticancer Drug Tamoxifen.

Among pollutants released into the environment by human activities, residues of pharmaceuticals are an increasing matter of concern because of their potential impact on ecosystems. The aim of this study was to analyze differences of protein expression resulting from acute (2 days) and middle-term (7 days) exposure of aquatic microcrustacean Daphnia pulex to the anticancer drug tamoxifen. Using a liquid chromatography-mass spectrometry shotgun approach, about 4000 proteins could be identified, providing the largest proteomics data set of D. pulex published up to now. Considering both time points and tested concentrations, 189 proteins showed a significant fold change. The identity of regulated proteins suggested a decrease in translation, an increase in protein degradation and changes in carbohydrate and lipid metabolism as the major effects of the drug. Besides these impacted processes, which reflect a general stress response of the organism, some other regulated proteins play a role in Daphnia reproduction. These latter results are in accordance with our previous observations of the impact of tamoxifen on D. pulex reproduction and illustrate the potential of ecotoxicoproteomics to unravel links between xenobiotic effects at the biochemical and organismal levels. Data are available via ProteomeXchange with identifier PXD001257.

Estimation de la fonction rénale par l'equation MDRD: intérêt et limites pour l'adaptation des doses de médicaments [Renal function estimation by MDRD equation: interest and limitations for drug dosing].

The MDRD (Modification of diet in renal disease) equation enables glomerular filtration rate (GFR) estimation from serum creatinine only. Thus, the laboratory can report an estimated GFR (eGFR) with each serum creatinine assessment, increasing therefore the recognition of renal failure. Predictive performance of MDRD equation is better for GFR < 60 ml/min/1,73 m2. A normal or near-normal renal function is often underestimated by this equation. Overall, MDRD provides more reliable estimations of renal function than the Cockcroft-Gault (C-G) formula, but both lack precision. MDRD is not superior to C-G for drug dosing. Being adjusted to 1,73 m2, MDRD eGFR has to be back adjusted to the patient's body surface area for drug dosing. Besides, C-G has the advantage of a greater simplicity and a longer use.

Traitement pharmacologique de l'état de mal réfractaire [Drug treatment of refractory status epilepticus]

Status epilepticus (SE) refractory to benzodiazepines and other antiepileptic agents is managed with intravenous anesthetic compounds, such as thiopental, propofol or midazolam. These drugs display quite different pharmacodynamic and pharmacokinetic properties, but have not been prospectively compared to date. Their use is clearly advocated for the treatment of generalized convulsive SE, whereas partial-complex, or absence SE are generally managed less aggressively, in consideration of their better prognosis. The most important aspect seems to be related to the correct use of these anesthetics in the right context, rather than the choice of one specific compound. An electroencephalographic burst-suppression should be targeted for about 24hour, before progressive weaning of the dosage under EEG monitoring. If this approach proves unsuccessful, the use of other drugs, including inhalational anesthetics, has been described.

The biochemistry of drug metabolism-an introduction: part 7. Intra-individual factors affecting drug metabolism.

This review on intra-individual factors affecting drug metabolism completes our series on the biochemistry of drug metabolism. The article presents the molecular mechanisms causing intra-individual differences in enzyme expression and activity. They include enzyme induction by transcriptional activation and enzyme inhibition on the protein level. The influencing factors are of physiological, pathological, or external origin. Tissue characteristics and developmental age strongly influence enzyme-expression patterns. Further influencing factors are pregnancy, disease, or biological rhythms. Xenobiotics, drugs, constituents of herbal remedies, food constituents, ethanol, and tobacco can all influence enzyme expression or activity and, hence, affect drug metabolism.

Evidências da relação entre a evolução da gestão ambiental e a adoção de práticas de green supply chain management no setor eletroeletrônico brasileiro

Na pesquisa apresentada, teve-se como objetivo verificar se a evolução da gestão ambiental se relaciona positivamente com a adoção de práticas de green supply chain management (GSCM) por empresas do setor eletroeletrônico do Brasil. Para fazer frente ao objetivo exposto, foi realizada uma pesquisa quantitativa, por meio de um levantamento survey, com cem empresas do setor eletroeletrônico brasileiro. Os dados coletados foram processados por meio de técnicas estatísticas descritivas, análise fatorial exploratória e modelagem de equações estruturais. Os resultados mais importantes da pesquisa foram: na amostra, práticas de GSCM orientadas para a recuperação dos investimentos das empresas, como a revenda de materiais inservíveis e outros resíduos, além da adequação à legislação e à auditoria ambiental, obtiveram médias elevadas; e a hipótese de pesquisa (H1) foi confirmada e considerada estatisticamente válida, indicando que a evolução da gestão ambiental influencia a adoção de práticas de GSCM.

Effects of triamcinolone acetonide on vessels of the posterior segment of the eye.

PURPOSE: This study investigates the effects of triamcinolone acetonide (TA) on retinal endothelial cells in vitro and explores the potential vascular toxic effect of TA injected into the vitreous cavity of rats in vivo. METHODS: Subconfluent endothelial cells were treated with either 0.1 mg/ml or 1 mg/ml TA in 1% ethanol. Control cells were either untreated or exposed to 1% ethanol. Cell viability was evaluated at 24 h, 72 h, and five days using the tetrazolium 3-(4,5-dimethylthiazol-2-yl)-2,5 phenyltetrazolium bromide test (MTT) and lactate dehydrogenase (LDH) assays. Cell proliferation was evaluated by 5-bromo-2-deoxyuridine (BrdU) test. Apoptosis was evaluated by terminal deoxynucleotidyl transferase dUTP nick end labeling assay (TUNEL assay), annexin-binding, and caspase 3 activation. Caspase-independent cell deaths were investigated by immunohistochemistry using antibodies against apoptosis inducing factor (AIF), cytochrome C, microtubule-associated protein (MAP)-light chain 3 (MAP-LC3), and Leukocyte Elastase Inhibitor/Leukocyte Elastase Inhibitor-derived DNase II (LEI/L-DNase II). In vivo, semithin and ultrathin structure analysis and vascular casts were performed to examine TA-induced changes of the choroidal vasculature. In addition, outer segments phagocytosis assay on primary retinal pigment epithelium (RPE) cells was performed to assess cyclooxygenase (COX-2) and vascular endothelial growth factor (VEGF) mRNAs upregulation with or without TA. RESULTS: The inhibitory effect of TA on cell proliferation could not explain the significant reduction in cell viability. Indeed, TA induced a time-dependent reduction of bovine retinal endothelial cells viability. Annexin-binding positive cells were observed. Cytochrome C was not released from mitochondria. L-DNase II was found translocated to the nucleus, meaning that LEI was changed into L-DNase II. AIF was found nuclearized in some cells. LC3 labeling showed the absence of autophagic vesicles. No autophagy or caspase dependent apoptosis was identified. At 1 mg/ml TA induced necrosis while exposure to lower concentrations for 3 to 5 days induced caspase independent apoptosis involving AIF and LEI/L-DNase II. In vivo, semithin and ultrathin structure analysis and vascular casts revealed that TA mostly affected the choroidal vasculature with a reduction of choroidal thickness and increased the avascular areas of the choriocapillaries. Experiments performed on primary RPE cells showed that TA downregulates the basal expression of COX-2 and VEGF and inhibits the outer segments (OS)-dependent COX-2 induction but not the OS-dependent VEGF induction. CONCLUSIONS: This study demonstrates for the first time that glucocorticoids exert direct toxic effect on endothelial cells through caspase-independent cell death mechanisms. The choroidal changes observed after TA intravitreous injection may have important implications regarding the safety profile of TA use in human eyes.

Administration intra-vitréenne de liposomes pour la vectorisation de principes actifs [The use of liposomes as intravitreal drug delivery system].

Liposomes are vesicular lipidic systems allowing encapsulation of drugs. This article reviews the relevant issues in liposome structure (composition and size), and their influence on intravitreal pharmacokinetics. Liposome-mediated drug delivery to the posterior segment of the eye via intravitreal administration has been addressed by several authors and remains experimental. Liposomes have been used for intravitreal delivery of antibiotics, antivirals, antifungal drugs, antimetabolites, and cyclosporin. Encapsulation of these drugs within liposomes markedly increased their intravitreal half-life, and reduced their retinal toxicity. Liposomes have also shown an attractive potential for retinal gene transfer by intravitreal delivery of plasmids or oligonucleotides.