Modeling the impact of heat stress on the toxicokinetics of toluene and acetone.

Many workers can be exposed simultaneously to heat and volatile chemicals. In a controlled human exposure study, it was observed that an increase in ambient temperature was associated with increased blood concentrations for acetone and toluene. Based on the expected changes in physiological parameters that occur with an increase in ambient temperature, we aimed to develop a PBPK model for acetone and toluene that could account for the impact of temperature on the kinetics of these solvents.

Determination of blood:air, urine:air and plasma:air partition coefficients of selected microbial volatile organic compounds.

Partition coefficients (PCs) are essential parameters for understanding the toxicokinetics of chemicals in the human body since they are used in the description of different processes of absorption, distribution, and excretion in physiologically based pharmacokinetic (PBPK) models used in chemical exposure and risk assessment. The goal of this study was to determine urine:air, blood:air and plasma:air partition coefficients (PCs) of microbial volatile organic compounds (mVOCs) previously selected as having high potential as biomarkers of indoor mold exposure. To achieve this goal, the vial-equilibration technique was used, and quantification was performed using headspace gas chromatography tandem mass spectrometry (HS-GC-MS/MS) analysis.

Full-scale multisampling and empirical modeling of DBPs in water and air of indoor pools.

Disinfection by-products (DBPs) are formed in the water in swimming pools due to reactions between disinfectants (chlorine, bromine, ozone) and the organic matter introduced by bathers and supply water. High concentrations of DBPs are also reported in the air of indoor swimming pools. Based on a robust multisampling program, the levels and variations of DBPs in the air (trichloramine [TCAM] and trihalomethanes [THMs]) and water (THM) were assessed, as well as their precursors (total organic carbon, water temperature, pH, free, and total chlorine) and proxies (CO and relative humidity) in four indoor chlorinated swimming pools.

Quantification of the Conjugated Forms of Dichlorobisphenol A (3,3'-Cl 2 BPA) in Rat and Human Plasma Using HPLC-MS/MS.

Background: Bisphenol A (BPA) is a ubiquitous contaminant that has endocrine-disrupting effects. Chlorinated derivatives of BPA are formed during chlorination of drinking water and have higher endocrine-disrupting activity. Dichlorobisphenol A (Cl 2 BPA) is the most abundant chlorinated BPA derivative found in several human biological matrices.

Comparison of sampling collection strategies for assessing airborne trichloramine levels in indoor swimming pools.

Since 1995, Hery's trichloramine sampling procedure has been widely used to determine trichloramine exposure in indoor swimming pools. This method consists of pumping air at a 1 L/min flow rate for 2 h through a Teflon prefilter and two quartz fiber filters. Modified Hery methods have been reported using different sampling pump flow rates and types of prefilters.

Toxicokinetics of silver element following inhalation of silver nitrate in rats.

Silver (Ag) and its compounds are priority contaminants, for which toxicological effects are well documented, but their toxicokinetics are not fully documented for a proper risk assessment. While the toxicokinetics of insoluble Ag nanoparticles (Ag NPs) was recently documented, there is a lack of data on the kinetic behavior of the soluble form, such as one of the mostly used silver nitrate (AgNO) form. This study aimed to better document the toxicokinetics of Ag element following inhalation of soluble AgNO for comparison with a previous study on the kinetics of inhaled Ag NPs using a similar experimental design.

A new headspace solid-phase microextraction coupled with gas chromatography-tandem mass spectrometry method for the simultaneous quantification of 21 microbial volatile organic compounds in urine and blood.

Mold growth can cause the development of several metabolites including microbial volatile organic compounds (mVOCs). These latter may be considered as potential biomarkers of fungal presence and have been detected in human biological matrices such as urine and blood. Exposure to molds and their metabolites (e.

Temporal and spatial variations in the levels of prominent airborne disinfection by-products at four indoor swimming pools.

Exposure to airborne disinfection by-products, especially trichloramine and trichloromethane, may cause various adverse health effects for the workers and users of indoor swimming pools. This study aims to evaluate the spatial and temporal variations in trichloramine and trichloromethane concentrations within and between swimming pools. Workplace measurements were carried out at four indoor swimming pools in Quebec (Canada) during the cold season.

Hepatic metabolism of chlorinated derivatives of bisphenol A (ClBPA) and interspecies differences between rats and humans.

During chlorination treatments of drinking water, aqueous bisphenol A (BPA) can react with chlorine to form chlorinated derivatives of BPA (mono, di, tri and tetra-chlorinated derivatives) or ClBPA. These emerging substances are endocrine disruptors associated with obesity, type II diabetes (TD2M) and myocardial infarction. ClBPA are present in different human biological matrices but their toxicokinetics remain unknown.

Cardiopulmonary parameters and organ blood flows for workers expressed in terms of VO2 for use in physiologically based toxicokinetic modeling.

Minute ventilation rates (VE), alveolar ventilation rates (VA), cardiac outputs (Q), liver blood flow (LBF) and kidneys blood flows (KBF) for physiologically based toxicokinetic modeling and occupational health risk assessment in active workers have apparently not been determined. Minute energy expenditure rates (E) and oxygen consumption rates (VO) in workers during exertions and their aggregate daytime activities are obtained by using open-circuit wearable devices for indirect calorimetry measurements and the doubly labeled water method respectively. Hundreds of E (in kcal/min) and VO (in L of O/min) were previously reported for workers.

Volatile organic compounds (VOCs) in indoor air and tap water samples in residences of pregnant women living in an area of unconventional natural gas operations: Findings from the EXPERIVA study.

Background: Northeastern British Columbia (Canada) is an area of unconventional natural gas (UNG) exploitation by hydraulic fracturing, which can release several contaminants, including volatile organic compounds (VOCs). To evaluate gestational exposure to contaminants in this region, we undertook the Exposures in the Peace River Valley (EXPERIVA) study.

Objectives: We aimed to: 1) measure VOCs in residential indoor air and tap water from EXPERIVA participants; 2) compare concentrations with those in the general population and explore differences related to sociodemographic and housing characteristics; and 3) determine associations between VOC concentrations and density/proximity to UNG wells.

Kinetic time courses of inhaled silver nanoparticles in rats.

Silver nanoparticles (Ag NPs) are priority substances closely monitored by health and safety agencies. Despite their extensive use, some aspects of their toxicokinetics remain to be documented, in particular following inhalation, the predominant route of exposure in the workplace. A same experimental protocol and exposure conditions were reproduced two times (experiments E1 and E2) to document the kinetic time courses of inhaled Ag NPs.

Impact of heat on biological concentrations of toluene and acetone resulting from exposure by inhalation: A pilot study.

Climatic conditions raise new concerns about the potential impact of heat on the absorption and kinetics of certain chemicals. The impact of 3 temperatures (21, 25 and 30 °C WBGT) on the toxicokinetics of toluene and acetone was therefore evaluated in five human subjects during controlled exposures in an inhalation chamber. Biological samples were collected and analyzed by GC-MS/MS.

Cardiopulmonary values and organ blood flows before and during heat stress: data in nine subjects at rest in the upright position.

Physiological changes associated with thermoregulation can influence the kinetics of chemicals in the human body such as alveolar ventilation (VA) and redistribution of blood flow to organs. In this study, the influence of heat stress on various physiological parameters was evaluated in nine male volunteers during sessions of exposure to wet-bulb globe temperatures (WBGT) of 21, 25, and 30 °C for 4 h. Skin and core temperatures and more than 20 cardiopulmonary parameters were measured.

A New Guidance for the Prediction of Hepatic Clearance in the Early Drug Discovery and Development from the in Vitro-to-in Vivo Extrapolation Method and an Approach for Exploring Whether an Albumin-Mediated Hepatic Uptake Phenomenon Could be Present Under in Vivo Conditions.

The in vitro-to-in vivo extrapolation (IVIVE) methods for predicting the hepatic clearance (CL) of drugs based on microsomal or hepatocyte data have certainly advanced; however, there is still place for improving the extrapolations from in vitro assays containing no plasma proteins. Accordingly, there is a discussion on whether the free drug hypothesis or an albumin (ALB)-mediated hepatic uptake phenomenon is the best scaling method. Therefore, the objectives of this study were to guide the prediction of CL and to diagnose which scaling method between the free drug hypothesis and ALB-mediated uptake could be more accurate; this, irrespective of the mechanism(s) governing CL if the drugs can get to the hepatocyte membrane.

A novel solution of using mixed reality in bowel and oral and maxillofacial surgical telepresence: 3D mean value cloning algorithm.

Background And Aim: Most of the mixed reality models used in the surgical telepresence are suffering from the discrepancies in the boundary area and spatial-temporal inconsistency due to the illumination variation in the video frames. The aim behind this work is to propose a new solution that helps produce the composite video by merging the augmented video of the surgery site and virtual hand of the remote expertise surgeon. The purpose of the proposed solution is to decrease the processing time and enhance the accuracy of merged video by decreasing the overlay and visualization error and removing occlusion and artefacts.

Estimation of toluene exposure in air from BMA (S-benzylmercapturic acid) urinary measures using a reverse dosimetry approach based on physiologically pharmacokinetic modeling.

This study aimed to use a reverse dosimetry PBPK modeling approach to estimate toluene atmospheric exposure from urinary measurements of S-benzylmercapturic acid (BMA) in a small group of individuals and to evaluate the uncertainty associated to urinary spot-sampling compared to 24-h collected urine samples. Each exposure assessment technique was developed namely to estimate toluene air exposure from BMA measurements in 24-h urine samples (24-h-BMA) and from distributions of daily urinary BMA spot measurements (DUBSM). Model physiological parameters were described based upon age, weight, size and sex.

Comparative Assessment of Extrapolation Methods Based on the Conventional Free Drug Hypothesis and Plasma Protein-Mediated Hepatic Uptake Theory for the Hepatic Clearance Predictions of Two Drugs Extensively Bound to Both the Albumin And Alpha-1-Acid Glycoprotein.

Bteich and coworkers recently demonstrated in a companion manuscript (J Pharm Sci 109: https://doi.org/10.1016/j.

Repeat induced abortion and adverse childhood experiences in Aquitaine, France: a cross-sectional survey.

Objective: The aim of the study was to analyse the relationship between adverse childhood experiences (ACEs) and repeat induced abortion, with regard to the potential effects of social deprivation and intimate partner violence.

Methods: An observational cross-sectional survey was conducted across each of the 25 abortion centres in Aquitaine, France, from 15 June to 15 September 2009. The sample comprised 806 women >18 years who had requested an induced abortion.

A Novel Solution of Using Mixed Reality in Bowel and Oral and Maxillofacial Surgical Telepresence: 3D Mean Value Cloning algorithm.

Background And Aim: Most of the Mixed Reality models used in the surgical telepresence are suffering from the discrepancies in the boundary area and spatial-temporal inconsistency due to the illumination variation in the video frames. The aim behind this work is to propose a new solution that helps produce the composite video by merging the augmented video of the surgery site and virtual hand of the remote expertise surgeon. The purpose of the proposed solution is to decrease the processing time and enhance the accuracy of merged video by decreasing the overlay and visualization error and removing occlusion and artefacts.

Impact of Extensive Plasma Protein Binding on the In Situ Hepatic Uptake and Clearance of Perampanel and Fluoxetine in Sprague Dawley Rats.

The main objective was to investigate the effect of albumin (ALB) and/or alpha-1-acid glycoprotein (AGP) on the hepatic clearance (CLh) of the drugs that bind, extensively, to both proteins. Isolated perfused livers from male Sprague Dawley rats (IPRL) were performed for perampanel (PER) and fluoxetine (FLU), using physiological solutions in four scenarios (n = 3 rats/scenario/drug): 1) without plasma proteins (WO), 2) with bovine ALB (40 g/L), 3) with bovine AGP (1 g/L), and 4) with mixture of both proteins (MIX). PER is poorly to moderately metabolized (hepatic extraction = 0.

Blood Neutrophil-to-Lymphocyte Ratio and Urine IL-8 Levels Predict the Type of Bacterial Urinary Tract Infection in Type 2 Diabetes Mellitus Patients.

Background: Extended-spectrum ß-lactamase (ESBL)-producing and are the most common uropathogens causing UTI (urinary tract infection) in type 2 diabetes mellitus (T2DM). Circulatory inflammatory markers such as C-reactive protein (CRP) and neutrophil-to-lymphocyte ratio (NLR) are usually dysregulated during UTI. However, the differential regulation of these inflammatory signatures during and UTI in T2DM has not been determined.

Impact of pesticide coexposure: an experimental study with binary mixtures of lambda-cyhalothrin (LCT) and captan and its impact on the toxicokinetics of LCT biomarkers of exposure.

This study aimed at gaining more insights into the impact of pesticide coexposure on the toxicokinetics of biomarkers of exposure. This was done by conducting an in vivo experimental case-study with binary mixtures of lambda-cyhalothrin (LCT) and captan and by assessing its impact on the kinetic profiles of LCT biomarkers of exposure. Groups of male Sprague-Dawley rats were exposed orally by gavage to LCT alone (2.