Lysophosphatidic acid induces the crosstalk between the endovascular human trophoblast and endothelial cells in vitro

Spiral artery remodeling at the maternal–fetal interface is crucial for successful pregnancy and requires the interaction between the first trimester trophoblast and the endothelial cells of the maternal vessels. However, the precise mechanism of this dialog has yet to be determined. The current study investigated whether lysophosphatidic acid (LPA) modulates trophoblast–endothelial crosstalk in vitro. HTR-8/SVneo trophoblast cell line (H8) was seeded on top of Geltrex, incubated with LPA or LPA + NS-398 (selective cyclooxygenase-2 inhibitor), LPA + 1400W (selective inducible nitric oxide synthase inhibitor) or LPA + IL-6 neutralizing antibody and assayed for tube formation to model the acquisition of trophoblast endovascular phenotype. The supernatants were collected and used as conditioned media (CM). To test trophoblast–endothelial crosstalk, the endothelial cell line EA.hy926 was incubated with trophoblast CM. The CM from LPA-induced tubulogenesis stimulated endothelial cells migration and did not modify the apoptosis. Soluble factors derived from cyclooxygenase-2 and IL-6 pathways were involved in H8–EA.hy926 interaction under the LPA effect. Moreover, LPA increased the levels of IL-6 mRNA by cyclooxygenase-2 pathway in H8 cells. Collectively, LPA promotes trophoblast–endothelial crosstalk in vitro and induces the release of trophoblast soluble factors that stimulate endothelial cells migration without changes in apoptosis. The evidence presented here provides new insights about an active role of LPA as a lipid mediator regulating vascular remodeling at the maternal–fetal interface.     

Interaction between Lysophosphatidic Acid,Prostaglandins and the Endocannabinoid System during the Window of Implantation in the Rat Uterus

Bioactive lipid molecules as lysophosphatidic acid (LPA), prostaglandins (PG) and endocannabinoids are important mediators of embryo implantation. Based on previous published data we became interested in studying the interaction between these three groups of lipid derivatives in the rat uterus during the window of implantation. Thus, we adopted a pharmacological approach in vitro using LPA, DGPP (a selective antagonist of LPA3, an LPA receptor), endocannabinoids’ receptor selective antagonists (AM251 and AM630) and non selective (indomethacin) and selective (NS-398) inhibitors of cyclooxygenase-1 and 2 enzymes. Cyclooxygenase isoforms participate in prostaglandins’ synthesis. The incubation of the uterus from rats pregnant on day 5 of gestation (implantation window) with LPA augmented the activity and the expression of fatty acid amide hydrolase, the main enzyme involved in the degradation of endocannabinoids in the rodent uteri, suggesting that LPA decreased endocannabinoids’ levels during embryo implantation. It has been reported that high endocannabinoids are deleterious for implantation. Also, LPA increased PGE2 production and cyclooxygenase-2 expression. The incubation of LPA with indomethacin or NS-398 reversed the increment in PGE2 production, suggesting that cyclooxygenase-2 was the isoform involved in LPA effect. PGs are important mediators of decidualization and vascularization at the implantation sites. All these effects were mediated by LPA3, as the incubation with DGPP completely reversed LPA stimulatory actions. Besides, we also observed that endocannabinoids mediated the stimulatory effect of LPA on cyclooxygenase-2 derived PGE2 production, as the incubation of LPA with AM251 or AM630 completely reversed LPA effect. Also, LPA augmented via LPA3 decidualization and vascularization markers. Overall, the results presented here demonstrate the participation of LPA3 in the process of implantation through the interaction with other groups of lipid molecules, prostaglandins and endocannabinoids, which prepare the uterine milieu for embryo invasion during the window of implantation.     

Therapy of uncomplicated falciparum malaria in Europe: MALTHER - a prospective observational multicentre study

ABSTRACT: BACKGROUND: Malaria continues to be amongst the most frequent infectious diseases imported to Europe. Whilst European treatment guidelines are based on data from studies carried out in endemic areas, there is a paucity of original prospective treatment data. The objective was to summarize data on treatments to harmonize and optimize treatment for uncomplicated malaria in Europe. METHODS: A prospective observational multicentre study was conducted, assessing tolerance and efficacy of treatment regimens for imported uncomplicated falciparum malaria in adults amongst European centres of tropical and travel medicine. RESULTS: Between December 2003 and 2009, 504 patients were included in 16 centres from five European countries. Eighteen treatment regimens were reported,, the top three being atovaquone-proguanil, mefloquine, and artemether-lumefantrine. Treatments significantly differed with respect to the occurrence of treatment changes (p=0.005) and adverse events (p=0.001), parasite and fever clearance times (p<0.001), and hospitalization rates (p=0.0066) and durations (p=0.001). Four recrudescences and two progressions to severe disease were observed. Compared to other regimens, quinine alone was associated with more frequent switches to second line treatment, more adverse events and longer inpatient stays. Parasite and fever clearance times were shortest with artemether-mefloquine combination treatment. Vomiting was the most frequent cause of treatment change, occurring in 5.5% of all patients but 9% of the atovaquone-proguanil group. CONCLUSIONS: This study highlights the heterogeneity of standards of care within Europe. A consensus discussion at European level is desirable to foster a standardized management of imported falciparum malaria.     

AIDS and associated malignancies

INTRODUCTION It has been over twenty years since the onset of the AIDS epidemic, and in spite of the tremendous progress made towards the understanding of the disease, the virus that causes the disease and the development of highly ef- fective anti-retrov…     

Automated analysis of living cells through the quantitative use of automated phase contrast microscopy

A simplified theory of image formation in phase contrast microscopy is presented. It is shown that the phase shift induced in light (related to the refractive index) by the observed object can be reconstructed, point by point, from the phase-contrast digitally sampled image through an appropriate algorithm. This allows one to make quantitative observations on unstained, living cells.     

The genotoxicity of nitrilotriacetic acid (NTA) in a somatic mutation and recombination test in Drosophila melanogaster

The genotoxicity of a chelating agent, the trisodium salt of nitrilotriacetic acid (NTA), was assessed in a somatic mutation and recombination test (SMART) in Drosophila melanogaster employing the wing hair markers mwh and flr3. The experiments were performed in parallel in two different laboratories (Padua, Italy and Schwerzenbach, Switzerland). The effectively absorbed doses of NTA, which was administered by feeding to larvae, were determined by a sensitive method employing [3H]leucine which allowed individual consumption levels to be measured. The particular pattern of clone induction produced by this compound suggests that NTA is active in inducing mitotic recombination and possibly aneuploidy in somatic cells of Drosophila. This is discussed in relation to the data present in the literature regarding the genotoxicity of NTA in a variety of experimental systems.     

Cytofluorometry of electromagnetically controlled cell dedifferentiation.

Cellular morphology changes, which appear related to dedifferentiation (despecialization), have been produced in vitro in the nucleated red blood cell of the frog. This has been achieved by controlled alterations in the electrochemical environment of these living cells, both by a selective modification of the ionic concentrations of an isotonic amphibian Ringer solution, and by the electromagnetic induction of pulsating current having specific waveform parameters. Laser flow microfluorometry shows that the modified Ringer solution is able, per se, to partially trigger the process in the same time interval that certain induced current waveforms can significantly affect the number of cells in the so-called dedifferentiated state. It has also been found that, for a given waveform, the repetition rate appears to have a significant effect on the rate of cell change. Preliminary automated image analysis of cell smears suggests that dedifferentiated and normal cells have the same integrated optical density but different nuclear areas. In conclusion, it appears that, after the initial electrochemical trigger, the early stage of the process, when the cells move from a state of specialized function to one of less specific activity, is the unfolding of their chromatin supercoil, not involving DNA synthesis. Then cytofluorometry allowed us to identify, for the first time, fundamental modifications which occur in the cell nucleus under electromagnetic exposure.     

Enzymatic hydrolysis of cellulosic materials: A kinetic study

A kinetic study of the enzymatic hydrolysis of two celluloses with different structural features was performed at various temperatures (26-50 degrees C). The enzymatic system consisted of three types of enzymes: E(1)-beta-1,4-glucan glucanohydrolase; E(2)-beta-1,4-glucan cellobiohydrolase; and E(3)-beta-glucosidase. A mathematical model for the mechanism of the hydrolysis of cellulosic materials catalyzed by a multienzymatic system was checked and a good rationalization of the experimental results was achieved. Uncompetitive and competitive glucose inhibition on E(1) and E(2), respectively, appeared to occur for both substrates. Inhibition by cellobiose was checked at 34 degrees C on one substrate. The V(max), K(m), and glucose inhibition constants were optimized and their dependence on temperature determined.