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Specific features of chromatographic determination of xanthophyll esters are studied using an example of marigold flower lutein diesters under reversed-phase HPLC conditions. The developed two-column method made it possible to establish that, in samples with a low solubility of carotenoids in the used solvent and on a chromatography column in using a mobile phase with a low solubility of carotenoids, the precipitation of diesters is possible, which detrimentally affects the accuracy of the chromatographic determination. A critical factor in this case isì temperature: the storage of samples (solutions) in a refrigerator is not always advisable, because freezing of the main components is possible. It was shown that the use of a mobile phase containing from 0 to 10 vol % acetonitrile in acetone at a temperature not lower than 20°C is acceptable for the separation of all-trans-lutein diesters from cis-derivatives of lutein and zeaxanthin derivatives on 'monomeric' C18-phases., Author(s): V. I. Deineka [sup.1] , T. G. Burzhinskaya [sup.1] , I. P. Blinova [sup.1] , L. A. Deineka [sup.1] Author Affiliations: (1) grid.445984.0, 0000 0001 2224 0652, Institute of [...]

BACKGROUND: Phthalates have been reported to impair fertility in various studies. However, evidence exploring the associations between phthalate metabolites in follicular fluid (FF) and reproductive outcomes is lacking. OBJECTIVES: To investigate the associations between phthalate metabolite concentrations in FF and in vitro fertilization/intracytoplasmic sperm injection (IVF/ICSI) outcomes among women recruited from a fertility clinic. METHODS: We included 641 women undergoing IVF/ICSI treatment from December 2018 to January 2020. The levels of eight phthalate metabolites, including monoethyl phthalate (MEP), mono-isobutyl phthalate (MiBP), mono-n- butyl phthalate (MBP), monobenzyl phthalate (MBzP), mono(2ethylhexyl) phthalate (MEHP), mono(2-ethyl-5-hydroxyhexyl) phthalate (MEHHP), mono(2-ethyl- 5-oxohexyl) phthalate (MEOHP), and mono(2ethyl-5-carboxypentyl) phthalate (MECPP), were quantified in FF collected on the oocyte retrieval day. Associations between quartiles of individual phthalate metabolite concentrations and nine IVF/ICSI outcomes, including oocyte yield, mature oocyte number, two distinct pronuclei (2PN) zygote number, fertilization rate, blastocyst formation rate, implantation, clinical pregnancy, miscarriage, and live birth, were estimated with generalized linear models. The effects of phthalate mixtures on IVF/ICSI outcomes were assessed using Bayesian kernel machine regression (BKMR) models. RESULTS: After adjusting for relevant confounders, elevated quartiles of MBzP, MEHHP, and MEHP in FF were inversely associated with the numbers of retrieved oocytes, mature oocytes, and 2PN zygotes (all p for trends DISCUSSION: Certain phthalate metabolites in FF are inversely associated with the numbers of retrieved oocytes, mature oocytes, and 2PN zygotes among women undergoing IVF/ICSI treatment. https://doi.org/10.1289/EHP11998, Introduction Infertility, defined as inability to achieve conception after 1 y of unprotected intercourse, has emerged as a prominent global concern, impacting ~15% of couples and exhibiting a consistent growth [...]

We studied the interaction of acyl derivatives of carbocyclic alcohols of steroid structure with nitrogenous bases in the ion source of a 'direct analysis in real time' (DART) mass spectrometer. The protonation of esters in the DART plasma is accompanied by the elimination of a corresponding acid (acyl derivatives of cholesterol, [beta]-sitosterol, and estradiol), interaction of the formed cation with a nitrogenous base to yield a derivative with a bound charge. This effect was not observed for cortisone acetate and betamethasone dipropionate, which is consistent with the absence of ions of deacyl derivatives in their DART mass spectra., Author(s): S. V. Goriainov [sup.1] [sup.2], C. Esparza [sup.2], D. I. Zhilyaev [sup.1] [sup.2], N. Yu. Polovkov [sup.1], R. S. Borisov [sup.1] [sup.2], V. G. Zaikin [sup.1] Author Affiliations: (1) [...]

The gut microbiome derived short chain fatty acids perform multitude of functions to maintain gut homeostasis. Here we studied how butyrate stymie enteric bacterial invasion in cell using a simplistic binary model. The surface of the mammalian cells is enriched with microdomains rich in cholesterol that are known as rafts and act as entry points for pathogens. We showed that sodium butyrate treated RAW264.7 cells displayed reduced membrane cholesterol and less cholera-toxin B binding coupled with increased membrane fluidity compared to untreated cells indicating that reduced membrane cholesterol caused disruption of lipid rafts. The implication of such cellular biophysical changes on the invasion of enteric pathogenic bacteria was assessed. Our study showed, in comparison to untreated cells, butyrate-treated cells significantly reduced the invasion of Shigella and Salmonella, and these effects were found to be reversed by liposomal cholesterol treatment, increasing the likelihood that the rafts' function against bacterial invasion. The credence of ex vivo studies found to be in concordance in butyrate fed mouse model as evident from the significant drift towards a protective phenotype against virulent enteric pathogen invasion as compared to untreated mice. To produce a cytokine balance towards anti-inflammation, butyrate-treated mice produced more of the gut tissue anti-inflammatory cytokine IL-10 and less of the pro-inflammatory cytokines TNF-[alpha], IL-6, and IFN-[gamma]. In histological studies of Shigella infected gut revealed a startling observation where number of neutrophils infiltration was noted which was correlated with the pathology and was essentially reversed by butyrate treatment. Our results ratchet up a new dimension of our understanding how butyrate imparts resistance to pathogen invasion in the gut. Keywords: Butyrate, Cholesterol, Lipid raft, Pathogen invasion, Author(s): Oishika Das[sup.1], Aaheli Masid[sup.1], Mainak Chakraborty[sup.1], Animesh Gope[sup.1], Shanta Dutta[sup.1] and Moumita Bhaumik[sup.1] Introduction The community of bacteria that lines the intestinal tract is an epitome of symbiotic relation [...]

A procedure for the determination of dexketoprofen trometamol in human plasma by liquid chromatography-mass spectrometry (HPLC-MS/MS) using ibuprofen as an internal standard was proposed and validated. The matrix effect on the analyte response value was estimated; its short-term and long-term stability in a biological matrix and an aqueous acetonitrile solution was investigated. In addition, the stability of the analyte after freezing and thawing of samples was studied. It was shown that the dilution of samples by one half does not affect the accuracy and precision of the analysis. The limit of detection and the lower limit of quantification were 0.01 [micro]g/mL; the linearity range was 0.01-8.50 [micro]g/mL (R.sup.2 = 0.9974); the total analysis time was 3.5 min. Intra- and interday accuracy values were in the ranges 96.66-100.00% and 94.97-97.92%, respectively. Sample preparation, including liquid-liquid extraction with ethyl acetate in an acidic medium, is simple and fast. The developed procedure was successfully tested on real plasma samples from healthy volunteers in the framework of a comparative study of the pharmacokinetics and bioequivalence of a generic drug., Author(s): A. P. Lakeev [sup.1] [sup.2], E. A. Yanovskaya [sup.1], O. S. Bryushinina [sup.1], Yu. G. Zyuz'kova [sup.1], G. A. Frelikh [sup.1], N. Yu. Abdrashitova [sup.1], V. V. Udut [sup.1] [...]

A procedure is developed and conditions are optimized for the preparation of natural water samples using liquidâliquid extraction without the preliminary filtration of acidified water and subsequent derivatization for the determination of trace concentrations of aliphatic carboxylic acids C6-C21 by gas chromatography-mass spectrometry. It is shown that, at the stage of extraction with hexane, less than one half of free carboxylic acids of this homologous series passes into the extract, while a significant amount is adsorbed on the walls of the extraction vessel, and they must be washed off with a solution of sodium carbonate in an ethanol-water mixture (4 : 1). Liquid-liquid extraction with hexane in combination with the conversion of acids to pentafluorobenzyl esters significantly simplifies the analysis procedure of natural waters containing suspended particles, humic substances and ensures the attainment of a limit of detection of 0.05 [mu]g/L for the analytes., Author(s): V. V. Khasanov [sup.1], A. I. Makarycheva [sup.1], Yu. G. Slizhov [sup.1] Author Affiliations: (1) grid.77602.34, 0000 0001 1088 3909, Tomsk State University, Department of Chemistry, , 634050, Tomsk, [...]

Purpose Environmental phthalate exposure has been associated with attention deficit disorders in children. We hypothesized that in children treated in the pediatric intensive care unit (PICU), circulating phthalates leaching from indwelling medical devices contribute to their long-term attention deficit. Methods Circulating plasma concentrations of di(2-ethylhexyl)phthalate (DEHP) metabolites were quantified in 100 healthy children and 449 children who had been treated in PICU and were neurocognitively tested 4 years later. In a development patient cohort (N = 228), a multivariable bootstrap study identified stable thresholds of exposure to circulating DEHP metabolites above which there was an independent association with worse neurocognitive outcome. Subsequently, in a second patient cohort (N = 221), the observed independent associations were validated. Results Plasma concentrations of DEHP metabolites, which were virtually undetectable [0.029 (0.027-0.031) [micro]mol/l] in healthy children, were 4.41 (3.76-5.06) [micro]mol/l in critically ill children upon PICU admission (P < 0.001). Plasma DEHP metabolite concentrations decreased rapidly but remained 18 times higher until PICU discharge (P < 0.001). After adjusting for baseline risk factors and duration of PICU stay, and further for PICU complications and treatments, exceeding the potentially harmful threshold for exposure to circulating DEHP metabolites was independently associated with the attention deficit (all P [less than or equal to] 0.008) and impaired motor coordination (all P [less than or equal to] 0.02). The association with the attention deficit was confirmed in the validation cohort (all P [less than or equal to] 0.01). This phthalate exposure effect explained half of the attention deficit in post-PICU patients. Conclusions Iatrogenic exposure to DEHP metabolites during intensive care was independently and robustly associated with the important attention deficit observed in children 4 years after critical illness. Clinicaltrials.gov identifier: NCT00214916., Author(s): S. Verstraete [sup.1], I. Vanhorebeek [sup.1], A. Covaci [sup.2], F. Güiza [sup.1], G. Malarvannan [sup.2], P. G. Jorens [sup.2] [sup.3], G. Van den Berghe [sup.1] Author Affiliations: (1) grid.5596.f, [...]

Background: Previous studies suggest that prenatal exposure to phthalates, ubiquitous synthetic chemicals, may adversely affect neurodevelopment. However, data are limited on how phthalates affect cognition, executive function, and behavioral function into adolescence. Objective: We aimed to investigate associations of prenatal phthalate exposure with neurodevelopment in childhood and adolescence in the Center for the Health Assessment of Mothers and Children of Salinas (CHAMACOS) study. Methods: We examined associations between maternal urinary phthalate metabolite concentrations measured twice during pregnancy and a range of neurodevelopmental outcomes from ages 7 through 16 y in the CHAMACOS birth cohort (n = 334). We used age-specific linear regression models and generalized estimating equation models to assess longitudinal effects and examined differences by sex. Results: Phthalate metabolites were detected in 88%-100% of samples, depending on the metabolite. Associations of phthalates with neurodevelopmental outcomes were largely null with some noteworthy patterns. Higher prenatal concentrations of metabolites of low-molecular weight phthalates ([SIGMA]LMW) were associated with more self-reported hyperactivity [[beta] = 0.8, 95% confidence interval (CI): 0.1, 1.4 per 2-fold increase in [SIGMA]LMW phthalates], attention problems ([beta] = 1.5, 95% CI: 0.7, 2.2), and anxiety ([beta] = 0.9, 95% CI: 0.0, 1.8) at age 16. We observed sex-specific differences for the sums of high-molecular-weight and di(2-ethylhexyl) metabolites and cognitive outcomes (e.g., b for Full-Scale IQ for boys= -1.9, 95% CI: -4.1, 0.3 and -1.7, 95% CI: -3.8, 0.3, respectively; [beta] for girls = 1.8, 95% CI: 0.1, 3.4 and 1.6, 95% CI: 0.0, 3.2, respectively; p-int = 0.01 for both). Conclusion: We found predominantly null associations of prenatal phthalates with neurodevelopment in CHAMACOS, and weak associations of [SIGMA]LMW phthalates with internalizing and externalizing behaviors in adolescence. No previous studies have examined associations of prenatal phthalate exposure with neurodevelopment into adolescence, an important time for manifestations of effects. https://doi.org/10.1289/EHP5165, Introduction Phthalates are a group of chemicals used in multiple consumer products (Hauser and Calafat 2005). Low-molecular-weight (LMW) phthalates are used in fragrances, cosmetics, and shampoos (ATSDR 1995, 2001; Harley [...]