Induction of oxidative stress, lysosome activation and autophagy by nanoparticles in human brain-derived endothelial cells.

Different types of NPs (nanoparticles) are currently under development for diagnostic and therapeutic applications in the biomedical field, yet our knowledge about their possible effects and fate in living cells is still limited. In the present study, we examined the cellular response of human brain-derived endothelial cells to NPs of different size and structure: uncoated and oleic acid-coated iron oxide NPs (8-9 nm core), fluorescent 25 and 50 nm silica NPs, TiO2 NPs (21 nm mean core diameter) and PLGA [poly(lactic-co-glycolic acid)]-PEO [poly(ethylene oxide)] polymeric NPs (150 nm). We evaluated their uptake by the cells, and their localization, generation of oxidative stress and DNA-damaging effects in exposed cells. We show that NPs are internalized by human brain-derived endothelial cells; however, the extent of their intracellular uptake is dependent on the characteristics of the NPs. After their uptake by human brain-derived endothelial cells NPs are transported into the lysosomes of these cells, where they enhance the activation of lysosomal proteases. In brain-derived endothelial cells, NPs induce the production of an oxidative stress after exposure to iron oxide and TiO2 NPs, which is correlated with an increase in DNA strand breaks and defensive mechanisms that ultimately induce an autophagy process in the cells.

Going beyond EGFR.

a substantial proportion of non-small-cell lung cancer (NSCLC), and adenocarcinoma in particular, depends on a so-called 'driver mutation' for their malignant phenotype. This genetic alteration induces and sustains tumorigenesis, and targeting of its protein product can result in growth inhibition, tumor response and increased patient survival. NSCLC can thus be subdivided into clinically relevant molecular subsets. Mutations in EGFR best illustrate the therapeutic relevance of molecular classification. This article reviews the scope of presently known driving molecular alterations, including ROS1, BRaF, KRaS, HER2 and PIK3Ca, with a special emphasis on aLK rearrangements, and outlines their potential therapeutic applications.

Parkinson's disease.

In advanced Parkinson's disease (PD), the emergence of symptoms refractory to conventional therapy poses therapeutic challenges. The success of deep brain stimulation (DBS) and advances in the understanding of the pathophysiology of PD have raised interest in noninvasive brain stimulation as an alternative therapeutic tool. The rationale for its use draws from the concept that reversing abnormalities in brain activity and physiology thought to cause the clinical deficits may restore normal functioning. Currently the best evidence in support of this concept comes from DBS, which improves motor deficits, and modulates brain activity and motor cortex physiology, although whether a causal interaction exists remains largely undetermined. Most trials of noninvasive brain stimulation in PD have applied repetitive transcranial magnetic stimulation (rTMS), targeting the motor cortex. Current studies suggest a possible therapeutic potential for rTMS and transcranial direct current stimulation (tDCS), but clinical effects so far have been small and negligible with regard to functional independence and quality of life. Approaches to potentiate the efficacy of rTMS include increasing stimulation intensity and novel stimulation parameters that derive their rationale from studies on brain physiology. These novel parameters are intended to simulate normal firing patterns or to act on the hypothesized role of oscillatory activity in the motor cortex and basal ganglia with regard to motor control and its contribution to the pathogenesis of motor disorders. Noninvasive brain stimulation studies will enhance our understanding of PD pathophysiology and might provide further evidence for potential therapeutic applications.

Risques rénaux des compléments alimentaires: une cause ignorée [Renal risks of dietary complements: a forgotten cause].

The use of dietary complements like vitamins, minerals, trace elements, proteins, aminoacids and plant-derived agents is prevalent in the general population, in order to promote health and treat diseases. Dietary complements are considered as safe natural products and are easily available without prescription. However, these can lead to severe renal toxicity, especially in cases of unknown pre-existing chronic kidney disease (CKD). In particular, Chinese herbs including aristolochic acid, high doses of vitamine C, creatine and protein complements may lead to acute and chronic renal failure, sometimes irreversible. Dietary complement toxicity should be suspected in any case of unexplained renal impairement. In the case of pre-existing CKD, the use of potentially nephrotoxic dietary complements should be screened for.

Comprehensive approach for the detection of antifungal compounds using a susceptible strain of Candida albicans and confirmation of in vivo activity with the Galleria mellonella model.

An efficient screening strategy for the identification of potentially interesting low-abundance antifungal natural products in crude extracts that combines both a sensitive bioautography assay and high performance liquid chromatography (HPLC) microfractionation was developed. This method relies on high performance thin layer chromatography (HPTLC) bioautography with a hypersusceptible engineered strain of Candida albicans (DSY2621) for bioactivity detection, followed by the evaluation of wild type strains in standard microdilution antifungal assays. Active extracts were microfractionated by HPLC in 96-well plates, and the fractions were subsequently submitted to the bioassay. This procedure enabled precise localisation of the antifungal compounds directly in the HPLC chromatograms of the crude extracts. HPLC-PDA-mass spectrometry (MS) data obtained in parallel to the HPLC antifungal profiles provided a first chemical screening about the bioactive constituents. Transposition of the HPLC analytical conditions to medium-pressure liquid chromatography (MPLC) allowed the efficient isolation of the active constituents in mg amounts for structure confirmation and more extensive characterisation of their biological activities. The antifungal properties of the isolated natural products were evaluated by their minimum inhibitory concentration (MIC) in a dilution assay against both wild type and engineered strains of C. albicans. The biological activity of the most promising agents was further evaluated in vitro by electron microscopy and in vivo in a Galleria mellonella model of C. albicans infection. The overall procedure represents a rational and comprehensive means of evaluating antifungal activity from various perspectives for the selection of initial hits that can be explored in more in-depth mode-of-action studies. This strategy is illustrated by the identification and bioactivity evaluation of a series of antifungal compounds from the methanolic extract of a Rubiaceae plant, Morinda tomentosa, which was used as a model in these studies.

Total synthesis of (-)-isoavenaciolide

An enantioselective approach to (-)-isoavenaciolide was achieved starting from 1- undecyn-3-ol. The synthesis relied upon the preparation of a chiral 4-silyloxy-2-alkenylborane by hydroboration of a protected 2,3-allenol and subsequent stereoselective addition to 2- thiophenecarboxaldehyde

De Novo Production of Metabolites by Fungal Co-culture of Trichophyton rubrum and Bionectria ochroleuca.

The co-cultivation of fungi has recently been described as a promising strategy to induce the production of novel metabolites through possible gene activation. A large screening of fungal co-cultures in solid media has identified an unusual long-distance growth inhibition between Trichophyton rubrum and Bionectria ochroleuca. To study metabolite induction in this particular fungal interaction, differential LC-MS-based metabolomics was performed on pure strain cultures and on their co-cultures. The comparison of the resulting fingerprints highlighted five de novo induced compounds, which were purified using software-oriented semipreparative HPLC-MS. One metabolite was successfully identified as 4″-hydroxysulfoxy-2,2″-dimethylthielavin P (a substituted trimer of 3,5-dimethylorsellinic acid). The nonsulfated form, as well as three other related compounds, were found in the pure strain culture of B. ochroleuca.

Ultrastructural evidence of exosome secretion by progenitor cells in adult mouse myocardium and adult human cardiospheres.

The demonstration of beneficial effects of cell therapy despite the persistence of only few transplanted cells in vivo suggests secreted factors may be the active component of this treatment. This so-called paracrine hypothesis is supported by observations that culture media conditioned by progenitor cells contain growth factors that mediate proangiogenic and cytoprotective effects. Cardiac progenitor cells in semi-suspension culture form spherical clusters (cardiospheres) that deliver paracrine signals to neighboring cells. A key component of paracrine secretion is exosomes, membrane vesicles that are stored intracellularly in endosomal compartments and are secreted when these structures fuse with the cell plasma membrane. Exosomes have been identified as the active component of proangiogenic effects of bone marrow CD34(+) stem cells in mice and the regenerative effects of embryonic mesenchymal stem cells in infarcted hearts in pigs and mice. Here, we provide electron microscopic evidence of exosome secretion by progenitor cells in mouse myocardium and human cardiospheres. Exosomes are emerging as an attractive vector of paracrine signals delivered by progenitor cells. They can be stored as an "off-the-shelf" product. As such, exosomes have the potential for circumventing many of the limitations of viable cells for therapeutic applications in regenerative medicine.

Stereoselective Acetate Aldol Reactions From Metal Enolates

This review deals with metal enolate-mediated stereoselective acetate aldol reactions. It summarizes recent advances on aldol additions of unsubstituted metal enolates from chiral auxiliaries, stoichiometric and catalytic Lewis acids, or acting in substrate- controlled reactions, which provide stereocontrolled aldol transformations that allow the efficient synthesis of structurally complex natural products.

Development of a Liver-specific Tet-On Inducible System for AAV Vectors and Its Application in the Treatment of Liver Cancer.

Recombinant adeno-associated virus (rAAV) are effective gene delivery vehicles that can mediate long-lasting transgene expression. However, tight regulation and tissue-specific transgene expression is required for certain therapeutic applications. For regulatable expression from the liver we designed a hepatospecific bidirectional and autoregulatory tetracycline (Tet)-On system (Tet(bidir)Alb) flanked by AAV inverted terminal repeats (ITRs). We characterized the inducible hepatospecific system in comparison with an inducible ubiquitous expression system (Tet(bidir)CMV) using luciferase (luc). Although the ubiquitous system led to luc expression throughout the mouse, luc expression derived from the hepatospecific system was restricted to the liver. Interestingly, the induction rate of the Tet(bidir)Alb was significantly higher than that of Tet(bidir)CMV, whereas leakage of Tet(bidir)Alb was significantly lower. To evaluate the therapeutic potential of this vector, an AAV-Tet(bidir)-Alb-expressing interleukin-12 (IL-12) was tested in a murine model for hepatic colorectal metastasis. The vector induced dose-dependent levels of IL-12 and interferon-γ (IFN-γ), showing no significant toxicity. AAV-Tet(bidir)-Alb-IL-12 was highly efficient in preventing establishment of metastasis in the liver and induced an efficient T-cell memory response to tumor cells. Thus, we have demonstrated persistent, and inducible in vivo expression of a gene from a liver-specific Tet-On inducible construct delivered via an AAV vector and proved to be an efficient tool for treating liver cancer.

FOSS License Selection and Code Management

With nearly 2,000 free and open source software (FLOSS) licenses, software license proliferation¿ can be a major headache for software development organizations trying to speed development through software component reuse, as well as companies redistributing software packages as components of their products. Scope is one problem: from the Free Beer license to the GPL family of licenses to platform-specific licenses such as Apache and Eclipse, the number and variety of licenses make it difficult for companies to ¿do the right thing¿ with respect to the software components in their products and applications. In addition to the sheer number of licenses, each license carries within it the author¿s specific definition of how the software can be used and re-used. Permissive licenses like BSD and MIT make it easy; software can be redistributed and developers can modify code without the requirement of making changes publicly available. Reciprocal licenses, on the other hand, place varying restrictions on re-use and redistribution. Woe to the developer who snags a bit of code after a simple web search without understanding the ramifications of license restrictions.

Role of trabectedin in the treatment of soft tissue sarcoma.

Interest in marine natural products has allowed the discovery of new drugs and trabectedin (ET-743, Yondelis), derived from the marine tunicate Ecteinascidia turbinata, was approved for clinical use in 2007. It binds to the DNA minor groove leading to interferences with the intracellular transcription pathways and DNA-repair proteins. In vitro antitumor activity was demonstrated against various cancer cell lines and soft tissue sarcoma cell lines. In phase I studies tumor responses were observed also in osteosarcomas and different soft tissue sarcoma subtypes. The most common toxicities were myelosuppression and transient elevation of liver function tests, which could be reduced by dexamethasone premedication. The efficacy of trabectedin was established in three phase II studies where it was administered at 1.5 mg/m2 as a 24 h intravenous infusion repeated every three weeks, in previously treated patients. The objective response rate was 3.7%-8.3% and the tumor control rate (which included complete response, partial response and stable disease) was obtained in half of patients for a median overall survival reaching 12 months. In nonpretreated patients the overall response rate was 17%. Twenty-four percent of patients were without progression at six months. The median overall survival was almost 16 months with 72% surviving at one year. Predictive factors of response are being explored to identify patients who are most likely to respond to trabectedin. Combination with other agents are currently studied with promising results. In summary trabectedin is an active new chemotherapeutic agents that has demonstrated its role in the armamentarium of treatments for patients with sarcomas.

Orthogonal protecting groups in the synthesis of tryptophanyl-hexahydropyrroloindoles

The synthesis of various polycyclic systems containing a C3aNi bond between a hexahydropyrrolo[2,3-b]indole and an indole tryptophan is described here. A series of experiments were performed to determine the best combination of five orthogonal protecting groups and the best reaction conditions for formation of said bond, which is a common feature among many recently discovered marine natural products.

Progress on Lamellarins

This review covers recent literature on the lamellarins, a family of marine natural products, and related analogs, encompassing synthetic strategies for total synthesis, structure-activity relationships (SAR), and studies on mechanisms of biological action, namely in the context of antitumor activity. It reviews work published from January 2008 to December 2010.