Validation of a GC-IDMS method for the metrologically traceable quantification of selected FAMEs in biodiesel

Current methods for the analysis of fatty acid methyl esters (FAMEs) in rapeseed oil based biodiesel refer to operationally defined measurands, which is a practical solution for routine analysis. In this paper, a new method for the SI-traceable quantification of selected FAMEs in biodiesel and its validation are described. This method has the potential to be a reference method for applications requiring structurally defined measurands and traceability to the SI as it allows direct comparisons to well characterised calibrants through the use of isotopically labelled analogues of the analytes as well as establishing of a full uncertainty budget. The method is based on gas chromatography-isotope dilution mass spectrometry. Its performance is demonstrated through its implementation and validation in two independent laboratories and is shown to provide reliable and traceable results for selected FAMEs in biodiesel test samples.JRC.D.2-Standards for Innovation and sustainable Developmen

Effect of preparation design on the fracture resistance and fracture patterns of 3D printed one-piece endodontic crowns.

STATEMENT OF PROBLEM The impact of various preparation designs on the fracture resistance and fracture type of mandibular premolars restored with 3 dimensionally (3D) printed, 1-piece endodontic crowns remains unclear. PURPOSE The purpose of this study was to investigate the effect of different preparation designs on the fracture resistance and fracture patterns of mandibular premolars restored with 3D printed 1-piece endodontic crowns after thermal aging. MATERIAL AND METHODS Forty-five freshly extracted mandibular premolars received 3 different preparation designs: with at least 2 intact cuspal walls (2CW), with only 1 intact cuspal wall (1CW), and no cuspal wall present (NoCW). One-piece endodontic crowns were designed by using a computer-aided design (CAD) software program, 3D printed, cemented to the prepared teeth with self-adhesive resin cement, and thermocycled between 5 °C and 55 °C in artificial saliva. Subsequently, all specimens were subjected to a fracture test. The results were statistically analyzed using 1-way ANOVA (α=.05), and fracture types of all specimens were examined using a light microscope. RESULTS The analysis of fracture resistance values across separate designs revealed no statistically significant differences (P>.05). Mean fracture resistance values were 724.5 N in 2CW, 713 N in 1CW, and 861 N in NoCW. In 2CW and 1CW, the 1-piece endodontic crowns mostly displayed Type III fractures, whereas those in NoCW exhibited a combination of Type II and Type III fractures. CONCLUSIONS The mandibular premolar 1-piece endodontic crowns tested in this study exhibited similar fracture resistance and type of fracture with different preparation designs

beta-3AR W64R Polymorphism and 30-Minute Post-Challenge Plasma Glucose Levels in Obese Children

Objective: In this study, we aimed to investigate the association of W64R polymorphism of the beta 3-adrenergic receptor gene (beta-3AR) with childhood obesity and related pathologies. Methods: beta-3AR gene W64R genotyping was carried out in 251 children aged 6-18 years. Of these subjects, 130 were obese (62 boys) and 121 were normal-weight (53 boys). In the obese group, fasting lipids, glucose and insulin levels were measured. Oral glucose tolerance test (OGTT) was performed in 75 of the obese patients. Results: The frequency of W64R genotype was similar in obese and nonobese children. In obese children, relative body mass index, waist-to-hip ratio, serum lipid, glucose and insulin levels, as well as homeostasis model assessment of insulin resistance (HOMA-IR) scores were not different between Arg allele carriers (W64R and R64R) and noncarriers (W64W). In 75 obese children, OGTT results showed that Arg allele carriers had significantly higher 30-minute glucose levels (p=0.027). Conclusion: W64R polymorphism of the beta-3AR gene is not associated with obesity and waist-to-hip ratio in Turkish children. Although there were no relationships between the genotypes and lipid, glucose/insulin levels or HOMA-IR, the presence of W64R variant seemed to have an unfavorable influence on early glucose excursion after glucose loading

Fatty Acid, Essential Oil and Phenolic Compositions of Alcea pallida and Alcea apterocarpa with Antioxidant, Anticholinesterase and Antimicrobial Activities

This study was the first phytochemical and biological activity report on Alcea pallida and Alcea apterocarpa extracts. The main constituents of the essential oils were identified as arachidic acid (34.2%) for A. pallida, and hexatriacontane (25.3%) for A. apterocarpa. The main constituents of the fatty acids obtained from petroleum ether extracts of A. pallida and A. apterocarpa were identified as palmitic acid (31.2%) and oleic acid (25.6%), respectively. The phenolic compositions of the samples were determined using HPLC (LC-20 liquid chromatographic system). A. pallida and A. apterocarpa showed the same peaks which were ascorbic, caffeic, salicylic and p-hydroxybenzoic acids and quercetin, respectively. Salicylic acid showed the highest abundance. Among the eight extracts, the acetone extract of A. pallida possessed the best ABTS cation radical scavenging activity and moderate butyryl-cholinesterase activity at 200 mu g/mL. The A. pallida acetone extract exhibited 53.12% inhibition in DPPH free radical scavenging activity method at 100 mu g/mL concentration. The acetone extract of A. pallida showed weak antimicrobial activity against Escherichia coli, Streptococcus pyogenes, Staphylococcus aureus, Pseudomonas aeruginosa and moderate activity against Candida albicans (inhibition zone diameter 16 mm). The acetone extract of A. apterocarpa showed moderate activity against C. albicans (inhibition zone diameter 14 mm) and S. aureus (inhibition zone diameter 13 mm); weak activity against E. coli., S0 pyogenes, and P. aeruginosa

The reliability and validity of the Turkish version of a childhood asthma control test

Bu çalışma, 11-15 Haziran 2011 tarihleri arasında İstanbul[Türkiye]’da düzenlenen 30. Congress of the European-Academy-of-Allergy-and-Clinical-Immunology (EAACI)’da bildiri olarak sunulmuştur.European Acad Allergy & Clin Immunol (EAACI

Defects along the T(H)17 differentiation pathway underlie genetically distinct forms of the hyper IgE syndrome

WOS: 000268860400023PubMed ID: 19577286Background: The hyper IgE syndrome (HIES) is characterized by abscesses, eczema, recurrent infections, skeletal and connective tissue abnormalities, elevated serum IgE, and diminished inflammatory responses. It exists as autosomal-dominant and autosomal-recessive forms that manifest common and distinguishing clinical features. A majority of those with autosomal-dominant HIES have heterozygous mutations in signal transducer and activator of transcription (STAT)-3 and impaired T(H)17 differentiation. Objective: To elucidate mechanisms underlying different forms of HIES. Methods: A cohort of 25 Turkish children diagnosed with HIES were examined for STAT3 mutations by DNA sequencing. Activation of STAT3 by IL-6 and IL-21 and STAT1 by IFN-alpha was assessed by intracellular staining with anti-phospho (p)STAT3 and -pSTAT1 antibodies. T(H)17 and T(H)1 cell differentiation was assessed by measuring the production of IL-17 and IFN-gamma, respectively. Results: Six subjects had STAT3 mutations affecting the DNA binding, Src homology 2, and transactivation domains, including 3 novel ones. Mutation-positive but not mutation-negative subjects with HIES exhibited reduced phosphorylation of STAT3 in response to cytokine stimulation, whereas pSTAT1 activation was unaffected. Both patient groups exhibited impaired TH17 responses, but whereas STAT3 mutations abrogated early steps in TH17 differentiation, the defects in patients with HIES with normal STAT3 affected more distal steps. Conclusion: In this cohort of Turkish children with HIES, a majority had normal STAT3, implicating other targets in disease pathogenesis. Impaired TH17 responses were evident irrespective of the STAT3 mutation status, indicating that different genetic forms of HIES share a common functional outcome. (J Allergy Clin Immunol 2009;124:342-8.)National Institutes of HealthUnited States Department of Health & Human ServicesNational Institutes of Health (NIH) - USA [5R01AI065617]Supported by National Institutes of Health grant 5R01AI065617 (T.C.)