scholarly journals Use of Site-Specific Data for Modeling Selenium Bioaccumulation by Terrestrial Animals

2021 ◽  
Author(s):  
Gary Santolo ◽  
Julie Yamamoto ◽  
Harry Ohlendorf
Keyword(s):  
Biological Monitoring ◽  
Common Species ◽  
Monitoring Data ◽  
Whole Body ◽  
Deer Mice ◽  
Regression Equations ◽  
Transfer Factors ◽  
Specific Data ◽  
Bird Eggs ◽  
Additional Sample

Abstract We developed a bioaccumulation model from an extensive set of monitoring data to predict selenium (Se) concentrations in biota within a terrestrial system (Kesterson Reservoir, CA). The model uses water-extractable Se concentrations in soil to estimate the expected range of mean Se concentrations in biota at Kesterson for future scenarios. Biological monitoring data collected at Kesterson Reservoir from 1988 to 1994 were used to parameterize the initial model. The model was tested and updated with additional sample results from 1995 through 2001 biological monitoring and validated and calibrated using Se concentrations from sampling conducted in 2004 and 2006. Minor adjustments were made to the model based on each additional year’s results and the model was used in 2014 to assess whether there were continuing threats to wildlife at Kesterson. The model predicts Se concentrations in small mammals, bird blood, and bird eggs in common species found at Kesterson. This model was used for the final assessment of Kesterson in 2014 and performed well, but there was variability in results due to differences in individual diets and feeding ranges of animals. In the comparisons of 2014 predicted to measured Se, only whole-body mice, deer mice (Peromyscus maniculatus), and kestrel blood were significantly different. The trophic transfer factors and regression equations should be applicable to other Se-contaminated sites; adjusting weighting factors based on diet and range allows the model to be adapted and used at other sites.

Interpretation of biological monitoring data in exposure to complex mixtures

2015 ◽  
Vol 238 (2) ◽  
pp. S20
Author(s):  
L. Godderis ◽  
R.-C. Duca ◽  
N. Grova ◽  
K. Poels ◽  
J. Vanoirbeek ◽  
...  
Keyword(s):  
Biological Monitoring ◽  
Complex Mixtures ◽  
Monitoring Data

Habitat use and abundance of deer mice: interactions with meadow voles and red-backed voles

1985 ◽  
Vol 63 (8) ◽  
pp. 1870-1879 ◽  
Author(s):  
Carlos Galindo ◽  
Charles J. Krebs
Keyword(s):  
Habitat Use ◽  
Relative Abundance ◽  
Deer Mouse ◽  
Common Species ◽  
Competitive Interactions ◽  
Deer Mice ◽  
Meadow Voles ◽  
Field Season ◽  
The Common ◽  
Clethrionomys Rutilus

In this study we investigated the influence of competitive interactions on the use of habitats and relative abundance of deer mice (Peromyscus maniculatus). If interspecific competition is influencing the habitat use and relative abundance of deer mice, then removal or introduction of potential competitors will change habitat use and abundance of this species. During the first field season we removed meadow voles (Microtus pennsylvanicus) to look at the effect on the contiguous population of deer mouse. The removal of one species had no effect on the other species' distribution or demography. In the second field season, meadow voles declined to very low numbers and we used their natural fluctuation as a removal experiment. Deer mouse populations were not affected even when the natural decline of meadow voles was more effective in maintaining the sedge meadow free of voles than the previous removal manipulation was. During the 3rd year, meadow voles colonized two areas of forest where deer mice had been alone the previous two field seasons. Red-backed voles (Clethrionomys rutilus), in turn, increased from very low numbers in four grids. Neither meadow voles nor red-backed voles affected the spatial distribution or abundance of deer mice. The results of this study indicate that competitive interactions have no influence on the use of habitats and relative abundance of the common species of small mammals in the southwestern Yukon.

Total Body Potassium and Body Fat Estimation in Relationship to Height, Sex, Age, Malnutrition and Obesity

1975 ◽  
Vol 48 (5) ◽  
pp. 431-440 ◽  
Author(s):  
C. J. Edmonds ◽  
B. M. Jasani ◽  
T. Smith
Keyword(s):  
Body Weight ◽  
Food Intake ◽  
Body Fat ◽  
Fat Free Mass ◽  
Whole Body ◽  
Regression Equations ◽  
Total Body Potassium ◽  
Normal Individuals ◽  
Males And Females ◽  
Total Body

1. Total body potassium was estimated by 40K measurement with a high-sensitivity whole-body counter in normal individuals over a wide age range and in patients who were obese or were grossly wasted as a result of various conditions which restricted food intake. 2. Potassium concentration (mmol/kg body weight) fell with increasing age over 30 years in both normal males and females, but when individuals of different age groups were matched for height, a significant fall in total body potassium with increasing age was observed only in males. Total body potassium of females was about 75% that of males of similar height when young, the sex difference decreasing with ageing. In the normal population, total body potassium was significantly correlated with height and with weight; regression equations for various relationships are given. 3. Fat-free mass was estimated from total body potassium, values of 65 and 56 mmol of potassium/kg fat-free mass being used for males and females respectively. Body fat estimated by this method correlated well with skinfold measurements over a wide range of body weight but in malnourished individuals having inadequate food intake there was considerable discrepancy and present formulae for estimating fat-free mass from total body potassium appear unsatisfactory in malnutrition. Considerable differences between expected and observed values of total body potassium were found in muscular individuals and in normal individuals who were thin but whose body weight was relatively constant. 4. The patients with malnutrition were low both in body fat as estimated by skinfold thickness and in total body potassium estimated on the basis of height. Plasma potassium was, however, normal and potassium supplements did not increase the total body potassium. 5. Total body potassium of obese individuals was not significantly different from that of normal weight individuals on the basis of height. Total body potassium fell on weight reduction with a very low energy diet of 1260 kJ (300 kcal.) daily but changed little with a 3300 kJ (800 kcal.) diet over several months' observation. 6. For overweight, obese individuals, total body potassium was best predicted from the individual's height. For those whose body weight was less than expected, the use of weight gave the best prediction but the error was considerable when the weight deviation was large.

scholarly journals ATTITUDE OF MEDICAL STUDENTS TO BODY DONATION IN THE NATIONAL UNIVERSITY OF CORDOBA – ARGENTINA. Actitud de los estudiantes de Medicina en relación a la donación de cuerpos en la Universidad Nacional de Córdoba – Argentina

2019 ◽  
Vol 11 (2) ◽  
pp. 70-83
Author(s):  
Susana Norma N. Biasutto ◽  
Marcos A. Spinelli ◽  
Diego M. Weigandt ◽  
Maria V. Mora ◽  
Atilio J. Bertocchi Valle ◽  
...  
Keyword(s):  
Demographic Data ◽  
Future Generations ◽  
Whole Body ◽  
Specific Data ◽  
Teaching Activities ◽  
Graduate Teaching ◽  
National University ◽  
Las Mujeres ◽  
Body Donation ◽  
De Medicina

Corpses for teaching and research in Anatomy are fundamental, even having high developed technological resources. Although the National University of Cordoba is receiving bodies by donation, the quantity is very scarce and it barely allows the pre-graduate teaching activities, using prosected specimens for practical activities. It is essential to develop a donation program to increase body supply. The objective of the present study is to obtain data about the attitude of Medicine students in relation to body procurement and donation. We collected demographic data to provided a framework for analysis and specific data on organ and body donation. Samples from students of each and all years of the career were considered. For the 97% of the students cadavers were very important to study Anatomy. Most of the total students (94%) should be willing to donate their organs for transplantation, 84% were interested in getting more information on body donation, 42% should donate their own body and 75% could participate in procurement actions. Women were more willing to donate their organs than men, while men were more willing to donate their own bodies. Students who did not profess any religion had better attitude to donation. Medicine students from the National University of Cordoba have evidenced an important commitment to donation not only of organs but also of whole body because they recognize their importance, care future generations and have high values like altruism and solidarity. La utilización de cuerpos humanos para docencia e investigación en el pre y posgrado resultan imprescindibles en Anatomía, aún disponiendo de tecnología de avanzada. Si bien la Universidad Nacional de Córdoba está recibiendo cuerpos por donación, la cantidad es muy escasa y apenas permite desarrollar las actividades docentes de pre-grado, usando preparados disecados para las actividades prácticas. Resulta imprescindible desarrollar un programa de donación para incrementar la provisión de cuerpos. El presente estudio pretende obtener datos que permitan conocer la actitud de los estudiantes de Medicina en relación a la procuración y donación de cuerpos. Se recabaron datos demográficos que brindaron un marco para el análisis y datos específicos sobre donación de órganos para trasplante y de cuerpos. Se consideraron muestras de alumnos correspondientes a todos los años de la carrera. Para el 97% los cuerpos son importantes para aprender Anatomía. El 94% donaría sus órganos para trasplante, al 84% le interesaría disponer de más información, el 42% donaría su propio cuerpo y el 75% participaría en un programa de procuración. Las mujeres tuvieron mayor disposición a la donación de órganos para trasplante, mientras que los varones hacia la donación de cuerpos (BD) para docencia e investigación. Quienes no profesan ninguna religión fueron más positivos hacia la BD. Los estudiantes de Medicina evidenciaron un importante compromiso con la donación tanto para trasplante como de cuerpos completos, porque reconocen la importancia de ambos, se preocupan por las generaciones futuras y cuentan con valores como el altruismo y la solidaridad.

scholarly journals Development, Testing, Parameterisation and Calibration of a Human PBPK Model for the Plasticiser, Di-(2-propylheptyl) Phthalate (DPHP) Using in Silico, in vitro and Human Biomonitoring Data

2021 ◽  
Vol 12 ◽  
Author(s):  
Kevin McNally ◽  
Craig Sams ◽  
Alex Hogg ◽  
Annie Lumen ◽  
George Loizou
Keyword(s):  
Sensitivity Analysis ◽  
Biological Monitoring ◽  
In Silico ◽  
Model Development ◽  
Human Biomonitoring ◽  
Urinary Metabolites ◽  
Monitoring Data ◽  
Pbpk Models ◽  
Lymphatic Uptake

A physiologically based pharmacokinetic model for Di-(2-propylheptyl) phthalate (DPHP) was developed to interpret the biokinetics in humans after single oral doses. The model was parameterized with in vitro and in silico derived parameters and uncertainty and sensitivity analysis was used during the model development process to assess structure, biological plausibility and behaviour prior to simulation and analysis of human biological monitoring data. To provide possible explanations for some of the counter-intuitive behaviour of the biological monitoring data the model included a simple lymphatic uptake process for DPHP and enterohepatic recirculation (EHR) for DPHP and the mono ester metabolite mono-(2-propylheptyl) phthalate (MPHP). The model was used to simultaneously simulate the concentration-time profiles of blood DPHP, MPHP and the urinary excretion of two metabolites, mono-(2-propyl-6-hydroxyheptyl) phthalate (OH-MPHP) and mono-(2-propyl-6-carboxyhexyl) phthalate (cx-MPHP). The availability of blood and urine measurements permitted a more robust qualitative and quantitative investigation of the importance of EHR and lymphatic uptake. Satisfactory prediction of blood DPHP and urinary metabolites was obtained whereas blood MPHP was less satisfactory. However, the delayed peak of DPHP concentration relative to MPHP in blood and second order metabolites in urine could be explained as a result of three processes: 1) DPHP entering the systemic circulation from the lymph, 2) rapid and very high protein binding and 3) the efficiency of the liver in removing DPHP absorbed via the hepatic route. The use of sensitivity analysis is considered important in the evaluation of uncertainty around in vitro and in silico derived parameters. By quantifying their impact on model output sufficient confidence in the use of a model should be afforded. This approach could expand the use of PBPK models since parameterization with in silico techniques allows for rapid model development. This in turn could assist in reducing the use of animals in toxicological evaluations by enhancing the utility of “read across” techniques.

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