A FABP4-PPARγ signaling axis regulates human monocyte responses to electrophilic fatty acid nitroalkenes

Nitro-fatty acids (NO2-FA) are electrophilic lipid mediators derived from unsaturated fatty acid nitration. These species are produced endogenously by metabolic and inflammatory reactions and mediate anti-oxidative and anti-inflammatory responses. NO2-FA have been postulated as partial agonists of the Peroxisome Proliferator-Activated Receptor gamma (PPARγ), which is predominantly expressed in adipocytes and myeloid cells. Herein, we explored molecular and cellular events associated with PPARγ activation by NO2-FA in monocytes and macrophages. NO2-FA induced the expression of two PPARγ reporter genes, Fatty Acid Binding Protein 4 (FABP4) and the scavenger receptor CD36, at early stages of monocyte differentiation into macrophages. These responses were inhibited by the specific PPARγ inhibitor GW9662. Attenuated NO2-FA effects on PPARγ signaling were observed once cells were differentiated into macrophages, with a significant but lower FABP4 upregulation, and no induction of CD36. Using in vitro and in silico approaches, we demonstrated that NO2-FA bind to FABP4. Furthermore, the inhibition of monocyte FA binding by FABP4 diminished NO2-FA-induced upregulation of reporter genes that are transcriptionally regulated by PPARγ, Keap1/Nrf2 and HSF1, indicating that FABP4 inhibition mitigates NO2-FA signaling actions. Overall, our results affirm that NO2-FA activate PPARγ in monocytes and upregulate FABP4 expression, thus promoting a positive amplification loop for the downstream signaling actions of this mediator.

Alternative RNA splicing of leucocyte tissue transglutaminase in coeliac disease

Tissue transglutaminase is a ubiquitous and multifunctional protein that contributes to several processes such as apoptosis/survival, efferocytosis, inflammation and tissue repairing under physiological and pathological conditions. Several activities can be associated with well-established functional domains; in addition, four RNA alternative splice variants have been described, characterized by sequence divergences and residues deletion at the C-terminal domains. Tissue transglutaminase is recognized as the central player in the physiopathology of coeliac disease (CD) mainly through calcium-dependent enzymatic activities. It can be hypothesized that differential regulation of tissue transglutaminase splice variants expression in persons with CD contributes to pathology by altering the protein functionality. We characterized the expression pattern of RNA alternative splice variants by RT-PCR in peripheral cells from patients with CD under free gluten diet adhesion; we considered inflammatory parameters and specific antibodies as markers of the stage of disease. We found significant higher expression of both the full length and the shortest C-truncated splice variants in leucocytes from patients with CD in comparison with healthy individuals. As tissue transglutaminase expression and canonical enzymatic activity are linked to inflammation, we studied the RNA expression of inflammatory cytokines in peripheral leucocytes of persons with CD in relation with splice variants expression; interestingly, we found that recently diagnosed patients showed significant correlation between both the full length and the shortest alternative spliced variants with IL-1 expression. Our results points that regulation of alternative splicing of tissue transglutaminase could account for the complex physiopathology of CD.

Decreasing gradient of antibiotic concentration in the lumen of catheters locked with vancomycin

The purpose of this study was to investigate if vancomycin concentration is maintained along the lumen of dialysis catheters after 48 h of lock therapy. Each lumen of nine catheters (three subclavian and six femoral) was locked with 2,500 mg/l of vancomycin for 48 h. After that period, the content of the lumen was aspirated with three different syringes of 0.4 ml each to measure the proximal, medial and distal vancomycin concentration. Vancomycin concentration was measured using a homogeneous particle-enhanced turbidimetric inhibition immunoassay. A non-parametric ANOVA, by means of a rank transformation on the antibiotic concentration, was used to assess the influence of the catheter segment (proximal, medial and distal) and the catheter type (femoral or subclavian). A significant decrease in vancomycin concentration from proximal to distal segments was observed (p < 0.001). In addition, the vancomycin concentration in subclavian catheters was significantly higher than in femoral catheters (p < 0.001). In our study there was a decreasing gradient in vancomycin concentration from proximal to distal segments of the catheter. This may explain the failure of antibiotic lock-therapy.

Impact of selective financing of drugs on pharmaceutical expenditure control in the province of Valladolid, Spain

In July 1993, public financing for 1692 drug specialities was stopped in Spain (a drug speciality is a medicine with a defined composition, particular pharmaceutical form and dosage, prepared for immediate use, ready and packaged for dispatching to the public, with uniform name, packaging and labelling which has been granted authorisation by the State Administration and registered in the Pharmaceutical Specialities Register). We designed a study to assess the repercussions of this so-called 'selective financing' on expenditure control. The aims of the study were 2-fold: first, to forecast the consumption of drug specialities that are reimbursable on the Spanish National Health Service, had selective financing not been applied; and, secondly, to estimate the impact of selective financing on drug consumption. For short- and medium-term forecast estimates, time-series analysis was used, and was applied to monthly consumption data. The measures of consumption used were the number of prescriptions per 1000 patients, and cost [in Spanish pesetas (Pta; $US1 = Pta123.9, February 1996)] per 1000 patients. Data were analysed from January 1986 up to the introduction of selective financing. We found that drug specialities excluded by selective financing showed, overall, a negative increase (i.e. the consumption of drugs that were excluded under selective financing decreased). The repercussion forecast, both in terms of prescription numbers and cost, of the 13 excluded drug specialities that had the highest pre-selective financing consumption is decreasing compared with total consumption. The assessment of the repercussions of selective financing up to December 1994 was made by calculating the difference between actual expenditures and forecast expenditures in the absence of selective financing. This repercussion, in prescriptions, was lower than the percentage of the 1692 excluded drug specialities relating to total consumption in 1992. The repercussion in cost, nevertheless, was greater than expected during the first year of selective financing application. This could be attributable to average price containment of drug specialities due to causes other than selective financing itself. The economic impact of selective financing after 1 year of application was reduced because of accommodation phenomena.

The prevalence of cocaine abuse during pregnancy in Barcelona

The aim of our study was to determine the prevalence of cocaine abuse, by means of positive urine toxicology screens or targeted questionnaire, among women in labor at our hospital. The prospective study included 1773 women who delivered consecutively in our institution. All of them underwent a standardized questionnaire including drug use and demographic data. Urine samples were obtained during labor. Urine toxicology screens for cocaine and its metabolites, opiates, and ethanol were performed by enzyme multiplied immunoassay technique. Information was coded in order to maintain anonymity. Among the 1773 women in labor we screened, the mean age was 27.8 years and the overall prevalence of a positive questionnaire for cocaine was 0.3% and a positive urine toxicology was 0.8%. Results by drug and by demographic items are analysed. There was a substantial denial of cocaine use among the toxicologically positive patients, since only 43% of them referred its use at any time during pregnancy, in conclusion, the use of illicit drugs is common among pregnant women in our institution, but cocaine does not seem to be as prevalent as it is in the USA, while in the labor room most women with a positive test do not refer the use of the drug. Urine toxicology screening increases the rate of detection of substance abuse in this population of women. These studies are necessary to target educational programs among pregnant women.