Download or read book Cell Culture Models of Biological Barriers written by Claus-Michael Lehr and published by CRC Press. This book was released on 2002-08-08 with total page 695 pages. Available in PDF, EPUB and Kindle. Book excerpt: Over the past ten years several sophisticated in vitro test systems based on epithelial cell cultures have been introduced in the field of drug delivery. These models have been found to be very useful in characterizing the permeability of drugs across epithelial tissues, and in studying formulations or carrier systems for improved drug delivery and
Download or read book Test and Evaluation of Biological Standoff Detection Systems written by National Research Council and published by National Academies Press. This book was released on 2008-07-29 with total page 42 pages. Available in PDF, EPUB and Kindle. Book excerpt: A biological warfare agent (BWA) is a microorganism, or a toxin derived from a living organism, that causes disease in humans, plants, or animals or that causes the deterioration of material. The effectiveness of a BWA is greatly reduced if the attack is detected in time for the target population to take appropriate defensive measures. Therefore, the ability to detect a BWA, in particular to detect it before the target population is exposed, will be a valuable asset to defense against biological attacks. The ideal detection system will have quick response and be able to detect a threat plume at a distance from the target population. The development of reliable biological standoff detection systems, therefore, is a key goal. However, testing biological standoff detection systems is difficult because open-air field tests with BWAs are not permitted under international conventions and because the wide variety of environments in which detectors might be used may affect their performance. This book explores the question of how to determine whether or not a biological standoff detection system fulfills its mission reliably if we cannot conduct open-air field tests with live BWAs.
Download or read book Review of Testing and Evaluation Methodology for Biological Point Detectors written by National Research Council and published by National Academies Press. This book was released on 2005-06-16 with total page 38 pages. Available in PDF, EPUB and Kindle. Book excerpt: This report examines the proposed testing methodology and facility that the Department of Defense (DOD) will use to test and evaluate the effectiveness of its detection system against biological warfare agentsâ€"an issue that impacts battlefield missions as well as homeland security missions. The report assesses a proposal to construct a whole system live agent testing facility at West Center Test Center, Dugway Proving Ground in Utah for testing the Joint Biological Point Detection System (JBPDS). Because of scientific and schedule-related risks, the report recommends an alternate approach that focuses test and evaluation efforts on leveraging existing data, improving simulated biological agents for use in testing, testing in conditions that more closely resemble the actual field conditions where the JBPDS would be deployed, and modeling for predicted performance against actual biological agents. The report concludes that an integrated testing and evaluation plan encompassing all of these factors will be needed.
Download or read book Biological Test Systems to Assess Health Effects of Exposure to Complex Mixtures written by Marvin S. Legator and published by . This book was released on 1984* with total page 213 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Model Based Hypothesis Testing in Biomedicine written by Rikard Johansson and published by Linköping University Electronic Press. This book was released on 2017-10-03 with total page 102 pages. Available in PDF, EPUB and Kindle. Book excerpt: The utilization of mathematical tools within biology and medicine has traditionally been less widespread compared to other hard sciences, such as physics and chemistry. However, an increased need for tools such as data processing, bioinformatics, statistics, and mathematical modeling, have emerged due to advancements during the last decades. These advancements are partly due to the development of high-throughput experimental procedures and techniques, which produce ever increasing amounts of data. For all aspects of biology and medicine, these data reveal a high level of inter-connectivity between components, which operate on many levels of control, and with multiple feedbacks both between and within each level of control. However, the availability of these large-scale data is not synonymous to a detailed mechanistic understanding of the underlying system. Rather, a mechanistic understanding is gained first when we construct a hypothesis, and test its predictions experimentally. Identifying interesting predictions that are quantitative in nature, generally requires mathematical modeling. This, in turn, requires that the studied system can be formulated into a mathematical model, such as a series of ordinary differential equations, where different hypotheses can be expressed as precise mathematical expressions that influence the output of the model. Within specific sub-domains of biology, the utilization of mathematical models have had a long tradition, such as the modeling done on electrophysiology by Hodgkin and Huxley in the 1950s. However, it is only in recent years, with the arrival of the field known as systems biology that mathematical modeling has become more commonplace. The somewhat slow adaptation of mathematical modeling in biology is partly due to historical differences in training and terminology, as well as in a lack of awareness of showcases illustrating how modeling can make a difference, or even be required, for a correct analysis of the experimental data. In this work, I provide such showcases by demonstrating the universality and applicability of mathematical modeling and hypothesis testing in three disparate biological systems. In Paper II, we demonstrate how mathematical modeling is necessary for the correct interpretation and analysis of dominant negative inhibition data in insulin signaling in primary human adipocytes. In Paper III, we use modeling to determine transport rates across the nuclear membrane in yeast cells, and we show how this technique is superior to traditional curve-fitting methods. We also demonstrate the issue of population heterogeneity and the need to account for individual differences between cells and the population at large. In Paper IV, we use mathematical modeling to reject three hypotheses concerning the phenomenon of facilitation in pyramidal nerve cells in rats and mice. We also show how one surviving hypothesis can explain all data and adequately describe independent validation data. Finally, in Paper I, we develop a method for model selection and discrimination using parametric bootstrapping and the combination of several different empirical distributions of traditional statistical tests. We show how the empirical log-likelihood ratio test is the best combination of two tests and how this can be used, not only for model selection, but also for model discrimination. In conclusion, mathematical modeling is a valuable tool for analyzing data and testing biological hypotheses, regardless of the underlying biological system. Further development of modeling methods and applications are therefore important since these will in all likelihood play a crucial role in all future aspects of biology and medicine, especially in dealing with the burden of increasing amounts of data that is made available with new experimental techniques. Användandet av matematiska verktyg har inom biologi och medicin traditionellt sett varit mindre utbredd jämfört med andra ämnen inom naturvetenskapen, såsom fysik och kemi. Ett ökat behov av verktyg som databehandling, bioinformatik, statistik och matematisk modellering har trätt fram tack vare framsteg under de senaste decennierna. Dessa framsteg är delvis ett resultat av utvecklingen av storskaliga datainsamlingstekniker. Inom alla områden av biologi och medicin så har dessa data avslöjat en hög nivå av interkonnektivitet mellan komponenter, verksamma på många kontrollnivåer och med flera återkopplingar både mellan och inom varje nivå av kontroll. Tillgång till storskaliga data är emellertid inte synonymt med en detaljerad mekanistisk förståelse för det underliggande systemet. Snarare uppnås en mekanisk förståelse först när vi bygger en hypotes vars prediktioner vi kan testa experimentellt. Att identifiera intressanta prediktioner som är av kvantitativ natur, kräver generellt sett matematisk modellering. Detta kräver i sin tur att det studerade systemet kan formuleras till en matematisk modell, såsom en serie ordinära differentialekvationer, där olika hypoteser kan uttryckas som precisa matematiska uttryck som påverkar modellens output. Inom vissa delområden av biologin har utnyttjandet av matematiska modeller haft en lång tradition, såsom den modellering gjord inom elektrofysiologi av Hodgkin och Huxley på 1950?talet. Det är emellertid just på senare år, med ankomsten av fältet systembiologi, som matematisk modellering har blivit ett vanligt inslag. Den något långsamma adapteringen av matematisk modellering inom biologi är bl.a. grundad i historiska skillnader i träning och terminologi, samt brist på medvetenhet om exempel som illustrerar hur modellering kan göra skillnad och faktiskt ofta är ett krav för en korrekt analys av experimentella data. I detta arbete tillhandahåller jag sådana exempel och demonstrerar den matematiska modelleringens och hypotestestningens allmängiltighet och tillämpbarhet i tre olika biologiska system. I Arbete II visar vi hur matematisk modellering är nödvändig för en korrekt tolkning och analys av dominant-negativ-inhiberingsdata vid insulinsignalering i primära humana adipocyter. I Arbete III använder vi modellering för att bestämma transporthastigheter över cellkärnmembranet i jästceller, och vi visar hur denna teknik är överlägsen traditionella kurvpassningsmetoder. Vi demonstrerar också frågan om populationsheterogenitet och behovet av att ta hänsyn till individuella skillnader mellan celler och befolkningen som helhet. I Arbete IV använder vi matematisk modellering för att förkasta tre hypoteser om hur fenomenet facilitering uppstår i pyramidala nervceller hos råttor och möss. Vi visar också hur en överlevande hypotes kan beskriva all data, inklusive oberoende valideringsdata. Slutligen utvecklar vi i Arbete I en metod för modellselektion och modelldiskriminering med hjälp av parametrisk ”bootstrapping” samt kombinationen av olika empiriska fördelningar av traditionella statistiska tester. Vi visar hur det empiriska ”log-likelihood-ratio-testet” är den bästa kombinationen av två tester och hur testet är applicerbart, inte bara för modellselektion, utan också för modelldiskriminering. Sammanfattningsvis är matematisk modellering ett värdefullt verktyg för att analysera data och testa biologiska hypoteser, oavsett underliggande biologiskt system. Vidare utveckling av modelleringsmetoder och tillämpningar är därför viktigt eftersom dessa sannolikt kommer att spela en avgörande roll i framtiden för biologi och medicin, särskilt när det gäller att hantera belastningen från ökande datamängder som blir tillgänglig med nya experimentella tekniker.
Download or read book Cell Culture Models of Biological Barriers written by Claus-Michael Lehr and published by CRC Press. This book was released on 2002-08-08 with total page 465 pages. Available in PDF, EPUB and Kindle. Book excerpt: Over the past ten years several sophisticated in vitro test systems based on epithelial cell cultures have been introduced in the field of drug delivery. These models have been found to be very useful in characterizing the permeability of drugs across epithelial tissues, and in studying formulations or carrier systems for improved drug delivery and
Download or read book Harmonization of Biological Testing Methodology written by LR. Williams and published by . This book was released on 1985 with total page 14 pages. Available in PDF, EPUB and Kindle. Book excerpt: The latitude provided in many written biological test methods, including ASTM standard practices, is such that different laboratories can produce widely varying test results on the same test materials while in technical compliance with the "method." One obvious solution to this problem is to standardize upon more tightly controlled, less flexible testing procedures. This approach, while widely accepted in the field of chemistry, has been strongly resisted by the biological testing community. This paper presents an alternative approach to achieving comparability of testing data among laboratories while retaining a high degree of flexibility for the individual laboratory. The keys to this approach are (1) the development and routine use of standard reference materials for test system calibration and control, (2) the development of "reference standard methods" that are sufficiently controlled that responses of the test systems to known test materials are predictable and reproducible, and (3) participation in external performance evaluation programs. Recommendations for implementation of a performance-based method evaluation program are offered.
Download or read book Ecotoxicology Monitoring written by Mervyn Richardson and published by Wiley-VCH Verlag GmbH. This book was released on 1993 with total page 424 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Chemical and Biological Terrorism written by Committee on R&D Needs for Improving Civilian Medical Response to Chemical and Biological Terrorism Incidents and published by National Academies Press. This book was released on 1999-02-26 with total page 303 pages. Available in PDF, EPUB and Kindle. Book excerpt: The threat of domestic terrorism today looms larger than ever. Bombings at the World Trade Center and Oklahoma City's Federal Building, as well as nerve gas attacks in Japan, have made it tragically obvious that American civilians must be ready for terrorist attacks. What do we need to know to help emergency and medical personnel prepare for these attacks? Chemical and Biological Terrorism identifies the R&D efforts needed to implement recommendations in key areas: pre-incident intelligence, detection and identification of chemical and biological agents, protective clothing and equipment, early recognition that a population has been covertly exposed to a pathogen, mass casualty decontamination and triage, use of vaccines and pharmaceuticals, and the psychological effects of terror. Specific objectives for computer software development are also identified. The book addresses the differences between a biological and chemical attack, the distinct challenges to the military and civilian medical communities, and other broader issues. This book will be of critical interest to anyone involved in civilian preparedness for terrorist attack: planners, administrators, responders, medical professionals, public health and emergency personnel, and technology designers and engineers.
Download or read book Drug Testing In Vitro written by Uwe Marx and published by John Wiley & Sons. This book was released on 2007-02-27 with total page 318 pages. Available in PDF, EPUB and Kindle. Book excerpt: Here, expert scientists from industry and academia share their knowledge on the assembly of functional human tissues in vitro and how to design drug screenings predictive of human exposure. In so doing, they combine the latest technological developments with strategic outlooks, such as novel cell and tissue systems for drug screening and testing, as well as emerging in vitro culture technologies. Equally importantly, the book does not shy away from regulatory acceptance and ethical issues.
Download or read book The Science and Applications of Synthetic and Systems Biology written by Institute of Medicine and published by National Academies Press. This book was released on 2011-12-30 with total page 570 pages. Available in PDF, EPUB and Kindle. Book excerpt: Many potential applications of synthetic and systems biology are relevant to the challenges associated with the detection, surveillance, and responses to emerging and re-emerging infectious diseases. On March 14 and 15, 2011, the Institute of Medicine's (IOM's) Forum on Microbial Threats convened a public workshop in Washington, DC, to explore the current state of the science of synthetic biology, including its dependency on systems biology; discussed the different approaches that scientists are taking to engineer, or reengineer, biological systems; and discussed how the tools and approaches of synthetic and systems biology were being applied to mitigate the risks associated with emerging infectious diseases. The Science and Applications of Synthetic and Systems Biology is organized into sections as a topic-by-topic distillation of the presentations and discussions that took place at the workshop. Its purpose is to present information from relevant experience, to delineate a range of pivotal issues and their respective challenges, and to offer differing perspectives on the topic as discussed and described by the workshop participants. This report also includes a collection of individually authored papers and commentary.
Download or read book Selecting Biological Test Systems to Assess Time Scale Toxicity written by Edwin E. Herricks and published by . This book was released on 1994-06-01 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Toxicologic Assessment of the Army s Zinc Cadmium Sulfide Dispersion Tests written by National Research Council and published by National Academies Press. This book was released on 1997-05-30 with total page 386 pages. Available in PDF, EPUB and Kindle. Book excerpt: During the 1950s and 1960s, the U.S. Army conducted atmospheric dispersion tests in many American cities using fluorescent particles of zinc cadmium sulfide (ZnCdS) to develop and verify meteorological models to estimate the dispersal of aerosols. Upon learning of the tests, many citizens and some public health officials in the affected cities raised concerns about the health consequences of the tests. This book assesses the public health effects of the Army's tests, including the toxicity of ZnCdS, the toxicity of surrogate cadmium compounds, the environmental fate of ZnCdS, the extent of public exposures from the dispersion tests, and the risks of such exposures.
Download or read book Biological Micro and Nanotribology written by Matthias Scherge and published by Springer Science & Business Media. This book was released on 2013-11-11 with total page 307 pages. Available in PDF, EPUB and Kindle. Book excerpt: By employing a combination of approaches from several disciplines the authors elucidate the principles of a variety of biomechanical systems that rely on frictional surfaces or adhesive secretions to attach parts of the body to one another or to attach organisms to a substrate. This account provides an excellent starting point for engineers and physicists working with biological systems and for biologists studying friction and adhesion. It will also serve as a valuable introduction for graduate students entering this interdisciplinary field of research.
Download or read book Biological Test Method written by and published by . This book was released on 1990 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Validation of Alternative Methods for Toxicity Testing written by Chantra Eskes and published by Springer. This book was released on 2016-09-26 with total page 418 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book provides information on best practices and new thinking regarding the validation of alternative methods for toxicity testing. It covers the validation of experimental and computational methods and integrated approaches to testing and assessment. Validation strategies are discussed for methods employing the latest technologies such as tissue-on-a-chip systems, stem cells and transcriptomics, and for methods derived from pathway-based concepts in toxicology. Validation of Alternative Methods for Toxicity Testing is divided into two sections, in the first, practical insights are given on the state-of-the-art and on approaches that have resulted in successfully validated and accepted alternative methods. The second section focuses on the evolution of validation principles and practice that are necessary to ensure fit-for-purpose validation that has the greatest impact on international regulatory acceptance of alternative methods. In this context validation needs to keep pace with the considerable scientific advancements being made in toxicology, the availability of sophisticated tools and techniques that can be applied in a variety of ways, and the increasing societal and regulatory demands for better safety assessment. This book will be a useful resource for scientists in the field of toxicology, both from industry and academia, developing new test methods, strategies or techniques, as well as Governmental and regulatory authorities interested in understanding the principles and practicalities of validation of alternative methods for toxicity testing.
Download or read book Biology Code written by National Research Council (U.S.). Chemical-Biological Coordination Center and published by . This book was released on 1960 with total page 236 pages. Available in PDF, EPUB and Kindle. Book excerpt:
