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Vlemincx Elke - - 2012
Vlemincx, E., J. L. Abelson, P. M. Lehrer, P. W. Davenport, I. Van Diest and O. Van den Bergh. Respiratory variability and sighing: A psychophysiological model. Whereas respiratory psychophysiological research has mainly studied respiratory time and volume, variability in these parameters has been largely disregarded, even though it may provide ...
Rodrigues G G - - 2012
Noninvasive mechanical ventilation is today often used to assist patient with chronic respiratory failure. One of the main reasons evoked to explain asynchrony events, discomfort, unwillingness to be treated, etc. is the occurrence of nonintentional leaks in the ventilation circuit which are difficult to account for because they are not ...
Pinheiro Luane L - - 2012
The aim of this work is to study the morphological characteristics of the trachea of Saimiri sciureus through quantification and measurement of the cartilaginous rings, providing information to facilitate the election of more appropriate endotracheal tube, laryngeal mask or tracheostomy tube for anesthetic and emergency procedures, as it is a ...
Smirnova O A - - 2012
ABSTRACT: Biologically motivated mathematical models, which describe the dynamics of the thrombocytopoietic, granulocytopoietic, and erythropoietic systems in irradiated humans, are thoroughly investigated. These models are the systems of nonlinear ordinary differential equations, whose variables and constant parameters have clear biological meaning. The modeling studies reveal general regularities and peculiarities of ...
Cengiz Mehmet Ali - - 2012
There is an increasing interest in the use of hospital admission for Chronic obstructive pulmonary disease (COPD) in studies of short-term exposure effects attributed to air pollutants. However, little is known about the effect of air pollutants on COPD symptoms. This study was undertaken to determine whether there was an ...
Bagnoli Paola - - 2012
Knowledge of the mechanical behavior of immature airways is crucial to understand the effects exerted by ventilation treatments, namely by Total Liquid Ventilation (TLV). A computational approach was adopted to investigate preterm airways in the range of pressure applied during TLV. A 3D finite-element model of the tracheal bifurcation was ...
Zou Xiaoming - - 2012
As organisms are typically exposed to chemical mixtures over long periods of time, chronic mixture toxicity is the best way to perform an environmental risk assessment (ERA). However, it is difficult to obtain the chronic mixture toxicity data due to the high expense and the complexity of the data acquisition ...
Vette Alan A United States Environmental Protection Agency, National Exposure Research Laboratory, 109 TW Alexander Dr., RTP, NC 27711, USA. - - 2013
The Near-Road Exposures and Effects of Urban Air Pollutants Study (NEXUS) was designed to examine the relationship between near-roadway exposures to air pollutants and respiratory outcomes in a cohort of asthmatic children who live close to major roadways in Detroit, Michigan USA. From September 2010 to December 2012 a total ...
Larcombe Alexander N - - 2012
Please cite this paper as: Larcombe et al. (2012) Factors influencing the assessment of lung function in mice with influenza-induced lung disease. Influenza and Other Respiratory Viruses DOI: 10.1111/irv.12034. Background  The constant-phase model (CPM) is commonly fit to respiratory system input impedance (Z(rs) ) to estimate lung mechanics. Driving signal frequencies ...
Ortega Rafael - - 2012
Capnography, the graphic display of the exhaled and inhaled carbon dioxide concentration plotted against time, is used to monitor ventilation. This video reviews the principles of capnography and explains how to interpret the information it provides.
Ma Baoshun B College of Medicine, University of Vermont, Burlington, VT 05405, United - - 2013
The explanted lung slice has become a popular in vitro system for studying how airways contract. Because the forces of airway-parenchymal interdependence are such important modulators of airway narrowing, it is of significant interest to understand how the parenchyma around a constricting airway in a lung slice behaves. We have ...
Asgharian Bahman - - 2012
The exposure-dose-response characterization of an inhalation hazard established in an animal species needs to be translated to an equivalent characterization in humans relative to comparable doses or exposure scenarios. Here, the first geometry model of the conducting airways for rhesus monkeys is developed based upon CT images of the conducting ...
Grassi Massimiliano - - 2012
BACKGROUND: The presence of abnormalities in baseline respiratory function of subjects with panic disorder (PD) is expected according to PD respiratory theories. We aimed to meta-analyze results from studies comparing baseline respiratory and hematic parameters related to respiration between subjects with PD and controls. METHODS: A literature research in bibliographic ...
Wong K - - 2012
Developing quantitative descriptions of how stimulant and depressant drugs affect the respiratory system is an important focus in medical research. Respiratory variables respiratory rate, tidal volume and end tidal carbon dioxide have prominent temporal dynamics that make it inappropriate to use standard hypothesis-testing methods that assume independent observations to assess ...
Unwin John - - 2012
OBJECTIVES: Thermoplastics may contain a wide range of additives and free monomers, which themselves may be hazardous substances. Laboratory studies have shown that the thermal decomposition products of common plastics can include a number of carcinogens and respiratory sensitizers, but very little information exists on the airborne contaminants generated during ...
Enoch Steven - - 2012
This study outlines how mechanistic organic chemistry related to covalent bond formation can be used to rationalise the ability of low molecular weight chemicals to cause respiratory sensitisation. The results of an analysis of 104 chemicals which have been reported to cause respiratory sensitisation in humans showed that most of ...
Shahly Victoria - - 2012
CONTEXT Insomnia is a common and seriously impairing condition that often goes unrecognized. OBJECTIVES To examine associations of broadly defined insomnia (ie, meeting inclusion criteria for a diagnosis from International Statistical Classification of Diseases, 10th Revision, DSM-IV, or Research Diagnostic Criteria/International Classification of Sleep Disorders, Second Edition) with costly workplace ...
Sakwari Gloria - - 2012
INTRODUCTION: Endotoxin exposure associated with organic dust exposure has been studied in several industries. Coffee cherries that are dried directly after harvest may differ in dust and endotoxin emissions to those that are peeled and washed before drying. The aim of this study was to measure personal total dust and ...
Mayhew Terry M - - 2012
For many organisms, respiratory gas exchange is a vital activity and different types of gas-exchange apparatus have evolved to meet individual needs. They include not only skin, gills, tracheal systems and lungs but also transient structures such as the chorioallantois of avian eggs and the placenta of eutherian mammals. The ...
Lázaro Jesús - - 2012
A method for deriving respiration from the pulse photoplethysmographic (PPG) signal is presented. This method is based on the pulse width variability (PWV), and it exploits the respiratory information present in the pulse wave velocity and dispersion. It allows to estimate respiration signal from only a pulse oximeter which is ...
Möhner Matthias M Department of Work and Health, Federal Institute for Occupational Safety and Health, Berlin, Germany. - - 2013
The present study sought to examine the long-term effects of exposure to respirable quartz on pulmonary function with particular focus on chronic obstructive pulmonary disease (COPD). The study is based on the Wismut cohort of former uranium miners. Spirometric data were ascertained together with quantitative estimates of cumulative exposure to ...
Duquenne Philippe - - 2012
Endotoxins are lipopolysaccharides found in the outer membrane of most Gram-negative bacteria and cyanobacteria. Worker exposure to endotoxins has been shown in a number of work situations and is associated with both respiratory and systemic pathologies. The lack of an occupational exposure limit is mainly due to the absence of ...
Pandia Keya - - 2012
Seismocardiography (SCG) is a non-invasive measurement of the vibrations of the chest caused by the heartbeat. SCG signals can be measured using a miniature accelerometer attached to the chest, and are thus well-suited for unobtrusive and long-term patient monitoring. Additionally, SCG contains information relating to both cardiovascular and respiratory systems. ...
Baker Nancy A - - 2012
Objective: Awkward postures during computer use are assumed to be related to the fit between the worker and the workstation configuration, with greater mismatches leading to higher levels of musculoskeletal symptoms (MSS). The objective of this study was to examine if chronic MSS of the neck/shoulder, back, and wrist/hands was ...
Cho Sook Ja - - 2012
We evaluated attenuation in linear associations between microbial exposure and respiratory symptoms occurring when individual measurements of microbial agents were used for estimating employees' exposure compared with group means. Symptoms, which improved when away from the building (building-related, BR), and measurements of culturable fungi, ergosterol, and endotoxin in floor dust ...
Smith Nicholas G - - 2013
To realistically simulate climate feedbacks from the land surface to the atmosphere, models must replicate the responses of plants to environmental changes. Several processes, operating at various scales, cause the responses of photosynthesis and plant respiration to temperature and CO2 to change over time of exposure to new or changing ...
Bosgra Sieto - - 2012
We developed a population physiology model, physB, which provides a statistical description of the physiological characteristics in the human population, in terms of the physiological parameters that are needed in physiologically based pharmacokinetic modelling. The model predicts individual organ weights, blood flows and some respiratory parameters from anthropometric properties (body ...
Carbonell Kathy M - - 2012
Vocal tremor can have a variety of physiological sources. For example, tremors can result from involuntary oscillation of respiratory muscles (respiratory tremor), or of the muscles responsible for vocal fold adduction (adductory tremor) or lengthening (f0 tremor). While the sources of vocal tremor are distinct, they are notoriously difficult to ...
Schranz C - - 2012
Patient-specific mathematical models of respiratory mechanics can offer substantial insight into patient state and pulmonary dynamics that are not directly measurable. Thus, they offer significant potential to evaluate and guide patient-specific lung protective ventilator strategies for Acute Respiratory Distress Syndrome (ARDS) patients. To assure bedside applicability, the model must be ...
Burgoyne Thomas T Electron Microscopy Unit, Royal Brompton Hospital, Sydney Street, London SW3 6NP, - - 2012
The ultrastructures of cilia and flagella are highly similar and well conserved through evolution. Consequently, Chlamydomonas is commonly used as a model organism for the study of human respiratory cilia. Since detailed models of Chlamydomonas axonemes were generated using cryoelectron tomography, disparities among some of the ultrastructural features have become ...
Harley N H - - 2012
The validation of human biological models for inhaled radionuclides is nearly impossible. Requirements for validation are: (1) the measurement of the relevant human tissue data and (2) valid exposure measurements over the interval known to apply to tissue uptake. Two lung models, ICRP 30(( 1)) and ICRP 66(( 2)), are ...
Evans Rhys L - - 2012
Pre-clinical evaluation of asthma therapies requires animal models of chronic airways inflammation, airway hyperresponsiveness (AHR) and lung remodelling that accurately predict drug effectiveness in human asthma. However, most animal models focus on acute allergen challenges where chronic inflammation and airway remodelling are absent. Chronic allergen challenge models have been developed ...
Lee S J - - 2012
Complicated breathing behaviors including uncertain and irregular patterns can affect the accuracy of predicting respiratory motion for precise radiation dose delivery [3-6, 25, 36]. So far investigations on irregular breathing patterns have been limited to respiratory monitoring of only extreme inspiration and expiration [37]. Using breathing traces acquired on a ...
Lourenço Clara Tavares - - 2012
For a better evaluation of the model using Apis mellifera in toxicology studies with insecticides, the oral acute toxicity of the insecticide fipronil against the stingless bee Melipona scutellaris was determined. The results showed that fipronil was highly toxic to M. scutellaris, with a calculated LC(50) (48 h) value of 0.011 ng a.i./μL ...
Sushko Iurii - - 2012
The article presents a Web-based platform for collecting and storing toxicological structural alerts from literature and for virtual screening of chemical libraries to flag potentially toxic chemicals and compounds that can cause adverse side effects. An alert is uniquely identified by a SMARTS template, a toxicological endpoint, and a publication ...
Gregorio Vincent - - 2012
Mixture risk assessment predictions have rarely been confronted with biological changes observed in the environment. In this study, long-term monitoring of a European great lake, Lake Geneva, provides the opportunity to assess to what extent the predicted toxicity of herbicide mixtures explains the changes in the composition of the phytoplankton ...
Tan Q - - 2012
Relating the toxicity of metals to their internal concentration is difficult due to the complicated detoxification processes within organisms. Only the metabolically available metals are potentially toxic to organisms, while metals in the detoxified form are toxicologically irrelevant. Accordingly, we developed a two-compartment toxicokinetic-toxicodynamic model for metals in a freshwater ...
Redman Aaron D - - 2012
A spreadsheet model (PETROTOX) is described that predicts the aquatic toxicity of complex petroleum substances from petroleum substance composition. Substance composition is characterized by specifying mass fractions in constituent hydrocarbon blocks (HBs), based on available analytical information. The HBs are defined by their mass fractions within a defined carbon number ...
Gubler Hanspeter - - 2012
The four-parameter logistic Hill equation models the theoretical relationship between inhibitor concentration and response and is used to derive IC(50) values as a measure of compound potency. This relationship is the basis for screening strategies that first measure percent inhibition at a single, uniform concentration and then determine IC(50) values ...
Lozano Norka Beatriz Huamá - - 2012
A quantitative structureactivity relationship analysis was employed to explore the relationship between the molecular structure of thiosemicarbazone analogues and the inhibition of the cysteine protease cruzain, a validated target for Chagas disease treatment. A data set containing 53 thiosemicarbazone derivatives was used to produce a quantitative model for activity prediction ...
Leblanc Heidi M K - - 2012
Pesticides are currently regulated individually but are present in aquatic systems as mixtures of toxicants. In this study, the lethal effects of three agricultural insecticides-chlorpyrifos, imidacloprid and dimethoate-on Chironomus dilutus larvae were examined. Ninety-six-hour static bioassays were performed using single, binary, and ternary toxicant mixtures. The effects of the binary ...
Coecke Sandra - - 2012
Toxicokinetics (TK) is the endpoint that informs about the penetration into and fate within the body of a toxic substance, including the possible emergence of metabolites. Traditionally, the data needed to understand those phenomena have been obtained in vivo. Currently, with a drive towards non-animal testing approaches, TK has been ...
Crawford J - - 2012
Biologically-targeted alpha-particle radiation is the basis of new and promising treatments for eliminating disseminated micrometastases and the residual microscopic malignancies that remain after surgery or radiation therapy. The short-range alpha-particles are highly cytotoxic and capable of inactivating single, isolated cancer cells which may otherwise cause recurrence. Astatine-211 is a promising ...
Capelli L - - 2012
This article describes an original approach for evaluating exposure to toxic odour emissions, based on methods commonly used for assessing the impact of odour, adopted in this specific case to examine the non-carcinogenic health effects of odours in the city of Terni, Italy. First the hazardous volatile organic compounds emitted ...
Lindsey Bruce G - - 2012
Computational models of the neural control system for breathing in mammals provide a theoretical and computational framework bringing together experimental data obtained from different animal preparations under various experimental conditions. Many of these models were developed in parallel and iteratively with experimental studies and provided predictions guiding new experiments. This ...
Zarfl Christiane - - 2012
According to the European legislation, REACH, organic compounds are considered as substances of very high concern (SVHC) if they are persistent, bioaccumulative and toxic (PBT). A substance's long-range transport potential (LRTP) may also pose a risk to remote regions. This is, however, not yet explicitly included. For identification of compounds, ...
Bell Harold J - - 2012
The invertebrates have adopted a myriad of breathing strategies to facilitate the extraction of adequate quantities of oxygen from their surrounding environments. Their respiratory structures can take a wide variety of forms, including integumentary surfaces, lungs, gills, tracheal systems, and even parallel combinations of these same gas exchange structures. Like ...
Greer John J - - 2012
Breathing movements have been demonstrated in the fetuses of every mammalian species investigated and are a critical component of normal fetal development. The classic sheep preparations instrumented for chronic fetal monitoring determined that fetal breathing movements (FBMs) occur in aggregates interspersed with long periods of quiescence that are strongly associated ...
Bergström Christel A S - - 2012
PURPOSE: To develop a computational model for predicting CNS drug exposure using a novel in vivo dataset. METHODS: The brain-to-plasma (B:P) ratio of 43 diverse compounds was assessed following intravenous administration to Swiss Outbred mice. B:P ratios were subjected to PLS modeling using calculated molecular descriptors. The obtained results were ...
Sutherland Jeffrey - - 2012
A primary goal of lead optimization is to identify compounds with improved absorption, distribution, metabolism, excretion and toxicity (ADMET) properties. A number of reports have linked computed molecular properties to desirable in vivo ADMET outcomes, but a significant limitation of these analyses is the failure to control statistically for possible ...
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