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https://www.readbyqxmd.com/read/28108195/the-virtual-cell-based-assay-current-status-and-future-perspectives
#1
Rabea Graepel, Lara Lamon, David Asturiol, Elisabet Berggren, Elisabeth Joossens, Alicia Paini, Pilar Prieto, Maurice Whelan, Andrew Worth
In order to replace the use of animals in toxicity testing, there is a need to predict in vivo toxic doses from concentrations that cause toxicological effects in relevant in vitro systems. The Virtual Cell Based Assay (VCBA) estimates time-dependent concentration of a test chemical in the cell and cell culture for a given in vitro system. The concentrations in the different compartments of the cell and test system are derived from ordinary differential equations, physicochemical parameters of the test chemical and properties of the cell line...
January 17, 2017: Toxicology in Vitro: An International Journal Published in Association with BIBRA
https://www.readbyqxmd.com/read/28108105/performance-of-predictive-equations-specifically-developed-to-estimate-resting-energy-expenditure-in-ventilated-critically-ill-children
#2
Corinne Jotterand Chaparro, Patrick Taffé, Clémence Moullet, Jocelyne Laure Depeyre, David Longchamp, Marie-Hélène Perez, Jacques Cotting
OBJECTIVE: To determine, based on indirect calorimetry measurements, the biases of predictive equations specifically developed recently for estimating resting energy expenditure (REE) in ventilated critically ill children, or developed for healthy populations but used in critically ill children. STUDY DESIGN: A secondary analysis study was performed using our data on REE measured in a previous prospective study on protein and energy needs in pediatric intensive care unit...
January 18, 2017: Journal of Pediatrics
https://www.readbyqxmd.com/read/28107289/pre-symptomatic-diagnosis-of-celiac-disease-in-predisposed-children-the-role-of-gene-expression-profile
#3
Martina Galatola, Donatella Cielo, Camilla Panico, Pio Stellato, Basilio Malamisura, Lorenzo Carbone, Carmen Gianfrani, Riccardo Troncone, Luigi Greco, Renata Auricchio
OBJECTIVE: The prevalence of Celiac Disease (CD) has increased significantly in recent years, and risk prediction and early diagnosis has become imperative especially in at risk families. In a previous study, we identified individuals with CD based on the expression profile of a set of candidate genes in peripheral blood monocytes. Here we evaluated the expression of a panel of CD candidate genes in peripheral blood mononuclear cells (PBMCs) from at risk infants long time before any symptom or production of antibodies...
January 20, 2017: Journal of Pediatric Gastroenterology and Nutrition
https://www.readbyqxmd.com/read/28107107/title-tobacco-alcohol-and-drug-use-of-people-with-mood-and-anxiety-disorders-differential-impact-of-family-and-friends
#4
Eunji Nam, Sadaaki Fukui
OBJECTIVE: Substance use among people with mood and anxiety disorders is highly prevalent. The literature suggests that substance use among people with mood and anxiety disorders is linked to social relational factors, yet it has been rarely the case that studies explicitly examine the differential impact of family and friends. This study investigated the association between family relationships, friendships, and substance use among people with mood and anxiety disorders. METHODS: Using the National Survey of American Life, structural equation modeling tested the unique effects of family relationships and friendships on tobacco, alcohol, and drug use (n = 1,076)...
January 20, 2017: Journal of Dual Diagnosis
https://www.readbyqxmd.com/read/28103880/the-use-of-genome-scale-metabolic-network-reconstruction-to-predict-fluxes-and-equilibrium-composition-of-n-fixing-versus-c-fixing-cells-in-a-diazotrophic-cyanobacterium-trichodesmium-erythraeum
#5
Joseph J Gardner, Nanette R Boyle
BACKGROUND: Computational, genome based predictions of organism phenotypes has enhanced the ability to investigate the biological phenomena that help organisms survive and respond to their environments. In this study, we have created the first genome-scale metabolic network reconstruction of the nitrogen fixing cyanobacterium T. erythraeum and used genome-scale modeling approaches to investigate carbon and nitrogen fluxes as well as growth and equilibrium population composition. RESULTS: We created a genome-scale reconstruction of T...
January 19, 2017: BMC Systems Biology
https://www.readbyqxmd.com/read/28100179/exploring-surface-cleaning-strategies-in-hospital-to-prevent-contact-transmission-of-methicillin-resistant-staphylococcus-aureus
#6
Hao Lei, Rachael M Jones, Yuguo Li
BACKGROUND: Cleaning of environmental surfaces in hospitals is important for the control of methicillin-resistant Staphylococcus aureus (MRSA) and other hospital-acquired infections transmitted by the contact route. Guidance regarding the best approaches for cleaning, however, is limited. METHODS: In this study, a mathematical model based on ordinary differential equations was constructed to study MRSA concentration dynamics on high-touch and low-touch surfaces, and on the hands and noses of two patients (in two hospitals rooms) and a health care worker in a hypothetical hospital environment...
January 18, 2017: BMC Infectious Diseases
https://www.readbyqxmd.com/read/28099162/thermography-based-blood-flow-imaging-in-human-skin-of-the-hands-and-feet-a-spectral-filtering-approach
#7
A A Sagaidachnyi, A V Fomin, D A Usanov, A V Skripal
The determination of the relationship between skin blood flow and skin temperature dynamics is the main problem in thermography-based blood flow imaging. Oscillations in skin blood flow are the source of thermal waves propagating from micro-vessels toward the skin's surface, as assumed in this study. This hypothesis allows us to use equations for the attenuation and dispersion of thermal waves for converting the temperature signal into the blood flow signal, and vice versa. We developed a spectral filtering approach (SFA), which is a new technique for thermography-based blood flow imaging...
January 18, 2017: Physiological Measurement
https://www.readbyqxmd.com/read/28097418/heterogeneous-network-epidemics-real-time-growth-variance-and-extinction-of-infection
#8
Frank Ball, Thomas House
Recent years have seen a large amount of interest in epidemics on networks as a way of representing the complex structure of contacts capable of spreading infections through the modern human population. The configuration model is a popular choice in theoretical studies since it combines the ability to specify the distribution of the number of contacts (degree) with analytical tractability. Here we consider the early real-time behaviour of the Markovian SIR epidemic model on a configuration model network using a multitype branching process...
January 17, 2017: Journal of Mathematical Biology
https://www.readbyqxmd.com/read/28097417/bistability-induced-by-generalist-natural-enemies-can-reverse-pest-invasions
#9
Sten Madec, Jérôme Casas, Guy Barles, Christelle Suppo
Analytical modeling of predator-prey systems has shown that specialist natural enemies can slow, stop and even reverse pest invasions, assuming that the prey population displays a strong Allee effect in its growth. We aimed to formalize the conditions in which spatial biological control can be achieved by generalists, through an analytical approach based on reaction-diffusion equations. Using comparison principles, we obtain sufficient conditions for control and for invasion, based on scalar bistable partial differential equations...
January 17, 2017: Journal of Mathematical Biology
https://www.readbyqxmd.com/read/28094999/specificity-of-executive-functioning-and-processing-speed-problems-in-common-psychopathology
#10
Joel T Nigg, Jennifer M Jester, Gillian M Stavro, Ka I Ip, Leon I Puttler, Robert A Zucker
OBJECTIVE: Interest continues in neuropsychological measures as cross-disorder intermediate phenotypes in understanding psychopathology. A central question concerns their specificity versus generalizability to particular forms of psychopathology, particularly for executive functioning (EF) and response speed. Three conceptual models examining these relationships were tested to clarify this picture at different levels in the diagnostic hierarchy. METHOD: Participants (total n = 641, age 18-60) yielded complete structured diagnostic interviews and a neuropsychological test battery comprising measures of executive function, processing speed, and IQ...
January 16, 2017: Neuropsychology
https://www.readbyqxmd.com/read/28093658/distinguishing-pathways-from-negative-emotions-to-suicide-ideation-and-to-suicide-attempt-the-differential-mediating-effects-of-nonsuicidal-self-injury
#11
Xu Zhang, Yaxuan Ren, Jianing You, Chao Huang, Yongqiang Jiang, Min-Pei Lin, Freedom Leung
Negative emotion (NE) is one of the most widely examined risk factors for suicide ideation (SI) and suicide attempt (SA). However, little is known about the possibly different mechanisms underlying the pathways from NE to these two different suicide phenomena. Nonsuicidal self-injury (NSSI) is related to both negative emotions and suicidality. Thus, the present study aimed to test the differential roles of NSSI in the pathways from NE (specified by depression, anxiety, and stress) to SI and from NE to SA. This study hypothesized that NSSI served as a mediator in the relationship from NE to SA, but not in the relationship from NE to SI...
January 17, 2017: Journal of Abnormal Child Psychology
https://www.readbyqxmd.com/read/28093202/sensorless-h%C3%A2-speed-tracking-synthesis-for-surface-mount-permanent-magnet-synchronous-motor
#12
Ramón Ramírez-Villalobos, Luis T Aguilar, Luis N Coria
In this paper, a sensorless speed tracking control is proposed for a surface-mount permanent magnet synchronous motor by using a nonlinear H∞-controller via stator currents measurements for feedback. An output feedback nonlinear H∞-controller was designed such that the undisturbed system is uniformly asymptotically stable around the desired speed reference, while also the effects of external vanishing and non-vanishing disturbances, noise, and input backlash were attenuated locally. The rotor position was calculated from the causal dynamic output feedback compensator and from the desired speed reference...
January 13, 2017: ISA Transactions
https://www.readbyqxmd.com/read/28092964/a-note-on-the-global-properties-of-an-age-structured-viral-dynamic-model-with-multiple-target-cell-populations
#13
Shaoli Wang, Jianhong Wu, Libin Rong
Some viruses can infect different classes of cells. The age of infection can affect the dynamics of infected cells and viral production. Here we develop a viral dynamic model with the age of infection and multiple target cell populations. Using the methods of semigroup and Lyapunov function, we study the global asymptotic property of the steady states of the model. The results show that when the basic reproductive number falls below 1, the infection is predicted to die out. When the basic reproductive number exceeds 1, there exists a unique infected steady state which is globally asymptotically stable...
June 1, 2017: Mathematical Biosciences and Engineering: MBE
https://www.readbyqxmd.com/read/28092954/modeling-and-simulation-for-toxicity-assessment
#14
Cristina Anton, Jian Deng, Yau Shu Wong, Yile Zhang, Weiping Zhang, Stephan Gabos, Dorothy Yu Huang, Can Jin
The effect of various toxicants on growth/death and morphology of human cells is investigated using the xCELLigence Real-Time Cell Analysis High Troughput in vitro assay. The cell index is measured as a proxy for the number of cells, and for each test substance in each cell line, time-dependent concentration response curves (TCRCs) are generated. In this paper we propose a mathematical model to study the effect of toxicants with various initial concentrations on the cell index. This model is based on the logistic equation and linear kinetics...
June 1, 2017: Mathematical Biosciences and Engineering: MBE
https://www.readbyqxmd.com/read/28092496/the-effect-of-contrast-material-on-radiation-dose-at-ct-part-i-incorporation-of-contrast-material-dynamics-in-anthropomorphic-phantoms
#15
Pooyan Sahbaee, W Paul Segars, Daniele Marin, Rendon C Nelson, Ehsan Samei
Purpose To develop a method to incorporate the propagation of contrast material into computational anthropomorphic phantoms for estimation of organ dose at computed tomography (CT). Materials and Methods A patient-specific physiologically based pharmacokinetic (PBPK) model of the human cardiovascular system was incorporated into 58 extended cardiac-torso (XCAT) patient phantoms. The PBPK model comprised compartmental models of vessels and organs unique to each XCAT model. For typical injection protocols, the dynamics of the contrast material in the body were described according to a series of patient-specific iodine mass-balance differential equations, the solutions to which provided the contrast material concentration time curves for each compartment...
January 13, 2017: Radiology
https://www.readbyqxmd.com/read/28092168/associations-between-at-risk-alcohol-use-substance-use-and-smoking-with-lipohypertrophy-and-lipoatrophy-among-patients-living-with-hiv
#16
Marisela Noorhasan, Daniel Drozd, Carl Grunfeld, Joe Merrill, Greer Burkholder, Michael J Mugavero, James H Willig, Amanda Willig, Karen L Cropsey, Kenneth Mayer, Aaron Blashill, Matthew Mimiaga, Mary E McCaul, Heidi Hutton, Geetanjali Chander, William C Matthews, Sonia Napravnik, Joseph J Eron, Katerina Christopoulos, Rob Fredericksen, Robin Nance, Joseph Chris Delaney, Paul Crane, Michael Saag, Mari M Kitahata, Heidi Crane
OBJECTIVE: To examine associations between lipohypertrophy and lipoatrophy and illicit drug use, smoking, and at-risk alcohol use among a large diverse cohort of persons living with HIV (PLWH) in clinical care. METHODS: 7,931 PLWH at 6 sites across the US completed 21,279 clinical assessments including lipohypertrophy and lipoatrophy, drug/alcohol use, physical activity level, and smoking. Lipohypertrophy and lipoatrophy were measured using the FRAM body morphology instrument and associations were assessed with generalized estimating equations...
January 16, 2017: AIDS Research and Human Retroviruses
https://www.readbyqxmd.com/read/28089531/predicting-the-particle-size-distribution-of-eroded-sediment-using-artificial-neural-networks
#17
María Paz Lagos-Avid, Carlos A Bonilla
Water erosion causes soil degradation and nonpoint pollution. Pollutants are primarily transported on the surfaces of fine soil and sediment particles. Several soil loss models and empirical equations have been developed for the size distribution estimation of the sediment leaving the field, including the physically-based models and empirical equations. Usually, physically-based models require a large amount of data, sometimes exceeding the amount of available data in the modeled area. Conversely, empirical equations do not always predict the sediment composition associated with individual events and may require data that are not always available...
January 12, 2017: Science of the Total Environment
https://www.readbyqxmd.com/read/28088545/how-do-people-s-perceptions-and-climatic-disaster-experiences-influence-their-daily-behaviors-regarding-adaptation-to-climate-change-a-case-study-among-young-generations
#18
Ying Deng, Ming Wang, Rasoul Yousefpour
Adaptation is a commonly applied strategy used to address individual behavior changes, in response to climate change. However, in-depth, evidence-based investigations of the relationships among individual perceptions, climatic disaster experiences, and daily behaviors regarding adaptation to climate change remain to be conducted. We obtained survey data from 488 respondents in southwestern China, a region prone to frequent and severe droughts, to assess factors that influence adaptive behaviors and to identify their pathways...
January 11, 2017: Science of the Total Environment
https://www.readbyqxmd.com/read/28088456/development-of-a-predictive-model-for-the-long-term-stability-assessment-of-drug-in-adhesive-transdermal-films-using-polar-pressure-sensitive-adhesives-as-carrier-matrix
#19
Clémence Chenevas-Paule, Hans-Michael Wolff, Mark Ashton, Martin Schubert, Kalliopi Dodou
Drug crystallization in transdermal drug delivery systems (TDDS) is a critical quality defect. The impact of drug load and hydration on the physical stability of polar (acrylic) drug-in-adhesive (DIA) films was investigated with the objective to identify predictive formulation parameters with respect to drug solubility and long-term stability. Medicated acrylic films were prepared over a range of drug concentrations below and above saturation solubility; and were characterized by FTIR, differential scanning calorimetry (DSC), polarized microscopy and Dynamic Vapor Sorption (DVS) analysis...
January 11, 2017: Journal of Pharmaceutical Sciences
https://www.readbyqxmd.com/read/28080145/neuropsychological-predictors-of-odd-symptom-dimensions-in-young-children
#20
Shayl F Griffith, David H Arnold, Benjamin Rolon-Arroyo, Elizabeth A Harvey
Oppositional defiant disorder (ODD) is a commonly diagnosed childhood behavior disorder, yet knowledge of relations between ODD and early neuropsychological functions, particularly independent of attention deficit/hyperactivity disorder (ADHD), is still limited. In addition, studies have not examined neuropsychological functioning as it relates to the different ODD symptom dimensions. Structural equation modeling was used to investigate how preschool neuropsychological functioning predicted negative affect, oppositional behavior, and antagonistic behavior symptom dimensions of ODD in 224 six-year-old children, oversampled for early behavior problems...
January 12, 2017: Journal of Clinical Child and Adolescent Psychology
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