WorldWideScience

Sample records for experimental animals mechanisms

  1. Animal experimentation

    OpenAIRE

    Laz, Alak; Cholakova, Tanya Stefanova; Vrablova, Sofia; Arshad, Naverawaheed

    2016-01-01

    Animal experimentation is a crucial part of medical science. One of the ways to define it is any scientific experiment conducted for research purposes that cause any kind of pain or suffering to animals. Over the years, the new discovered drugs or treatments are first applied on animals to test their positive outcomes to be later used by humans. There is a debate about violating ethical considerations by exploiting animals for human benefits. However, different ethical theories have been made...

  2. Animal experimentation.

    Science.gov (United States)

    Kolar, Roman

    2006-01-01

    Millions of animals are used every year in often times extremely painful and distressing scientific procedures. Legislation of animal experimentation in modern societies is based on the supposition that this is ethically acceptable when certain more or less defined formal (e.g. logistical, technical) demands and ethical principles are met. The main parameters in this context correspond to the "3Rs" concept as defined by Russel and Burch in 1959, i.e. that all efforts to replace, reduce and refine experiments must be undertaken. The licensing of animal experiments normally requires an ethical evaluation process, often times undertaken by ethics committees. The serious problems in putting this idea into practice include inter alia unclear conditions and standards for ethical decisions, insufficient management of experiments undertaken for specific (e.g. regulatory) purposes, and conflicts of interest of ethics committees' members. There is an ongoing societal debate about ethical issues of animal use in science. Existing EU legislation on animal experimentation for cosmetics testing is an example of both the public will for setting clear limits to animal experiments and the need to further critically examine other fields and aspects of animal experimentation.

  3. Cadmium osteotoxicity in experimental animals: Mechanisms and relationship to human exposures

    International Nuclear Information System (INIS)

    Bhattacharyya, Maryka H.

    2009-01-01

    Extensive epidemiological studies have recently demonstrated increased cadmium exposure correlating significantly with decreased bone mineral density and increased fracture incidence in humans at lower exposure levels than ever before evaluated. Studies in experimental animals have addressed whether very low concentrations of dietary cadmium can negatively impact the skeleton. This overview evaluates results in experimental animals regarding mechanisms of action on bone and the application of these results to humans. Results demonstrate that long-term dietary exposures in rats, at levels corresponding to environmental exposures in humans, result in increased skeletal fragility and decreased mineral density. Cadmium-induced demineralization begins soon after exposure, within 24 h of an oral dose to mice. In bone culture systems, cadmium at low concentrations acts directly on bone cells to cause both decreases in bone formation and increases in bone resorption, independent of its effects on kidney, intestine, or circulating hormone concentrations. Results from gene expression microarray and gene knock-out mouse models provide insight into mechanisms by which cadmium may affect bone. Application of the results to humans is considered with respect to cigarette smoke exposure pathways and direct vs. indirect effects of cadmium. Clearly, understanding the mechanism(s) by which cadmium causes bone loss in experimental animals will provide insight into its diverse effects in humans. Preventing bone loss is critical to maintaining an active, independent lifestyle, particularly among elderly persons. Identifying environmental factors such as cadmium that contribute to increased fractures in humans is an important undertaking and a first step to prevention.

  4. Ethics in Animal Experimentation

    Directory of Open Access Journals (Sweden)

    Yusuf Ergun

    2010-08-01

    Full Text Available Experimental animals are frequently used to obtain information for primarily scientific reasons. In the present review, ethics in animal experimentation is examined. At first, the history of animal experimentation and animal rights is outlined. Thereafter, the terms in relation with the topic are defined. Finally, prominent aspects of 3Rs constituting scientific and ethical basis in animal experimentation are underlined. [Archives Medical Review Journal 2010; 19(4.000: 220-235

  5. Is animal experimentation fundamental?

    Science.gov (United States)

    d'Acampora, Armando José; Rossi, Lucas Félix; Ely, Jorge Bins; de Vasconcellos, Zulmar Acciolli

    2009-01-01

    The understanding about the utilization of experimental animals in scientific research and in teaching is many times a complex issue. Special attention needs to be paid to attain the understanding by the general public of the importance of animal experimentation in experimental research and in undergraduate medical teaching. Experimental teaching and research based on the availability of animals for experimentation is important and necessary for the personal and scientific development of the physician-to-be. The technological arsenal which intends to mimic experimentation animals and thus fully replace their use many times does not prove to be compatible with the reality of the living animal. The purpose of this paper is to discuss aspects concerning this topic, bringing up an issue which is complex and likely to arouse in-depth reflections.

  6. Advantages of the experimental animal hollow organ mechanical testing system for the rat colon rupture pressure test.

    Science.gov (United States)

    Ji, Chengdong; Guo, Xuan; Li, Zhen; Qian, Shuwen; Zheng, Feng; Qin, Haiqing

    2013-01-01

    Many studies have been conducted on colorectal anastomotic leakage to reduce the incidence of anastomotic leakage. However, how to precisely determine if the bowel can withstand the pressure of a colorectal anastomosis experiment, which is called anastomotic bursting pressure, has not been determined. A task force developed the experimental animal hollow organ mechanical testing system to provide precise measurement of the maximum pressure that an anastomotic colon can withstand, and to compare it with the commonly used method such as the mercury and air bag pressure manometer in a rat colon rupture pressure test. Forty-five male Sprague-Dawley rats were randomly divided into the manual ball manometry (H) group, the tracing machine manometry pressure gauge head (MP) group, and the experimental animal hollow organ mechanical testing system (ME) group. The rats in each group were subjected to a cut colon rupture pressure test after injecting anesthesia in the tail vein. Colonic end-to-end anastomosis was performed, and the rats were rested for 1 week before anastomotic bursting pressure was determined by one of the three methods. No differences were observed between the normal colon rupture pressure and colonic anastomotic bursting pressure, which were determined using the three manometry methods. However, several advantages, such as reduction in errors, were identified in the ME group. Different types of manometry methods can be applied to the normal rat colon, but the colonic anastomotic bursting pressure test using the experimental animal hollow organ mechanical testing system is superior to traditional methods. Copyright © 2013 Surgical Associates Ltd. Published by Elsevier Ltd. All rights reserved.

  7. [Animal experimentation, animal welfare and scientific research].

    Science.gov (United States)

    Tal, H

    2013-10-01

    Hundreds of thousands of laboratory animals are being used every year for scientific experiments held in Israel, mostly mice, rats, rabbits, guinea pigs, and a few sheep, cattle, pigs, cats, dogs, and even a few dozen monkeys. In addition to the animals sacrificed to promote scientific research, millions of animals slain every year for other purposes such as meat and fine leather fashion industries. While opening a front against all is an impossible and perhaps an unjustified task, the state of Israel enacted the Animal Welfare (Animal Experimentation) Law (1994). The law aims to regulate scientific animal experiments and to find the appropriate balance between the need to continue to perform animal experiments for the advancement of research and medicine, and at the same time to avoid unnecessary trials and minimize animal suffering. Among other issues the law deals with the phylogenetic scale according to which experimental animals should be selected, experiments for teaching and practicing, and experiments for the cosmetic industry. This article discusses bioethics considerations in animal experiments as well as the criticism on the scientific validity of such experiments. It further deals with the vitality of animal studies and the moral and legal obligation to prevent suffering from laboratory animals.

  8. The rights of man and animal experimentation.

    OpenAIRE

    Martin, J

    1990-01-01

    Since emotions give contradictory signals about animal experimentation in medical science, man's relationship to animals must be based upon reason. Thomas Aquinas argues that man is essentially different from animals because man's intellectual processes show evidence of an abstract mechanism not possessed by animals. Man's rights arise in association with this essential difference. The consequence is that only man possesses true rights by Aquinas's definition; animals have them only by analog...

  9. [Ethical issue in animal experimentation].

    Science.gov (United States)

    Parodi, André-Laurent

    2009-11-01

    In the 1970s, under pressure from certain sections of society and thanks to initiatives by several scientific research teams, committees charged with improving the conditions of laboratory animals started to be created, first in the United States and subsequently in Europe. This led to the development of an ethical approach to animal experimentation, taking into account new scientific advances. In addition to the legislation designed to provide a legal framework for animal experimentation and to avoid abuses, this ethical approach, based on the concept that animals are sentient beings, encourages greater respect of laboratory animals and the implementation of measures designed to reduce their suffering. Now, all animal experiments must first receive ethical approval--from in-house committees in the private sector and from regional committees for public institutions. Very recently, under the impetus of the French ministries of research and agriculture, the National committee for ethical animal experimentation published a national ethical charter on animal experimentation, setting the basis for responsible use of animals for scientific research and providing guidelines for the composition and functioning of ethics committees. Inspired by the scientific community itself this ethical standardization should help to assuage--but not eliminate--the reticence and hostility expressed by several sections of society.

  10. Animal Experimentation in High Schools

    Science.gov (United States)

    Ansevin, Kystyna D.

    1970-01-01

    Recommends that teacher and student be provided with the broadest possible spectrum of meaningful and feasible experiments in which the comfort of the experimental animal is protected by the design of the experiment. (BR)

  11. [The ethics of animal experimentation].

    Science.gov (United States)

    Goffi, Jean-Yves

    2013-01-01

    The paper starts with a short definition of animal experimentation, then three main approaches to the practice are considered: unconditional approval (as advocated by Claude Bernard), conditional and restricted approval (as advocated by Peter Singer) and strict prohibition (as advocated by Tom Regan and Gary Francione). It is argued that what is actually approved or condemned in animal experimentation is the value of the scientific enterprise.

  12. The rights of man and animal experimentation.

    Science.gov (United States)

    Martin, J

    1990-01-01

    Since emotions give contradictory signals about animal experimentation in medical science, man's relationship to animals must be based upon reason. Thomas Aquinas argues that man is essentially different from animals because man's intellectual processes show evidence of an abstract mechanism not possessed by animals. Man's rights arise in association with this essential difference. The consequence is that only man possesses true rights by Aquinas's definition; animals have them only by analogy. However, cruelty to animals is illicit and they should be protected, principally not because they have rights, but because he who is cruel to animals is more likely to be cruel to his fellowman. If there is a need for animal experimentation in science for the good of man, this approach gives philosophical justification for experimentation, since man's well-being must come before that of animals because of his unique possession of rights. However, those experiments should be carried out in the kindest way possible, to promote kindness towards man. To see man as solely part of a biological continuum in competition for rights with those beings close to him biologically, detracts from man's dignity. PMID:2135948

  13. Animal rights and animal experimentation. Implications for physicians.

    Science.gov (United States)

    Gelpi, A. P.

    1991-01-01

    Practicing physicians are just becoming aware of the animal rights movement, which during the 1980s spawned numerous acts of violence against research facilities throughout the United States. The animal rightists are challenging physicians to show moral justification for the human exploitation of nature and the world of subhuman species. They have aroused public interest in animal welfare, sparked protective legislation for experimental animals, and indirectly encouraged the creation of committees to oversee the conduct of animal experimentation and the conditions of animal confinement. This controversy has necessitated a closer look at the questions of animal experimentation and animal rights against the backdrop of human experimentation and human rights. Physicians and specialists in animal care seek to alleviate suffering and anxiety, and, as moderates, they may be able to bring both sides of the animal rights controversy together in a spirit of mutual tolerance and in the common cause of promoting both human and animal welfare. PMID:1949772

  14. Bioavailability and the mechanisms of intestinal absorption of iron from ferrous ascorbate and ferric polymaltose in experimental animals

    International Nuclear Information System (INIS)

    Johnson, G.; Jacobs, P.

    1990-01-01

    The comparative bioavailability from matching quantities of iron in the form of ferrous ascorbate or ferric polymaltose was defined in rats. Studies were carried out in the intact animals under basal conditions and also when requirements for this metal were either increased or decreased by manipulating stores or erythropoietic activity. No significant difference was found in the total quantity of iron absorbed from either salt or complex under any of these circumstances, suggesting that the mucosal mechanism regulating the overall process was common to both. However, the rate of transfer from the lumen into portal blood was distinctive, reaching a maximum with salt at 30 min compared to 24 h for the complex. To explore the possibility that iron from the two sources was initially handled by different subcellular pathways, the radiolabeled compounds were instilled into loops of bowel that had been isolated between ligatures in vivo. Enterocytes were harvested and fractionated, and incorporation into ferritin and transferrin was determined using RIA. From salt, iron appeared rapidly in duodenal but not ileal ferritin, whereas mucosal transferrin increased under conditions of stimulated absorption, suggesting that this protein may act as a shuttle for the metal. In contrast, iron from polymaltose showed a cumulative incorporation into duodenal ferritin over time that correlated with iron absorption, defined by the appearance of radiolabel in the serum and in the carcass; a similar pattern was demonstrable in ileal mucosal cells. Conversely, binding of iron to transferrin was minimal. No iron polymaltose was found within the mucosal cells. It is suggested that the low rate of iron transfer from this ferric complex may reflect its extracellular breakdown in the lumen of the gastrointestinal tract

  15. Macrophages and Uveitis in Experimental Animal Models

    Directory of Open Access Journals (Sweden)

    Salvador Mérida

    2015-01-01

    Full Text Available Resident and infiltrated macrophages play relevant roles in uveitis as effectors of innate immunity and inductors of acquired immunity. They are major effectors of tissue damage in uveitis and are also considered to be potent antigen-presenting cells. In the last few years, experimental animal models of uveitis have enabled us to enhance our understanding of the leading role of macrophages in eye inflammation processes, including macrophage polarization in experimental autoimmune uveoretinitis and the major role of Toll-like receptor 4 in endotoxin-induced uveitis. This improved knowledge should guide advantageous iterative research to establish mechanisms and possible therapeutic targets for human uveitis resolution.

  16. Establishment for quality control of experimental animal

    International Nuclear Information System (INIS)

    Kim, Tae Hwan; Kim, Soo Kwan; Kim, Tae Kyoung

    1999-06-01

    Until now, because we have imported experimental animal from foreign experimental animal corporation, we could have saved money by establishing the quality control of animal in barrier system. In order to improve the quality of animal experiment and efficiency of biomedical study, it is indispensable to control many factors that effect in the experiment. Therefore, it is essential to organize the system of laboratory animal care for enhancing reliability and revivability of experimental results. The purpose of the present investigation was to establish the quality control system of experimental animals that we can provide good quality animals according to the experimental condition of each investigator although the exact quality control system to estimate the infection of bacteria and virus easily remains ill-defined yet. Accordingly, we established the useful quality control system for microbiologic monitoring and environmental monitoring to protect experimental animal from harmful bacteria and virus

  17. Establishment for quality control of experimental animal

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Tae Hwan; Kim, Soo Kwan; Kim, Tae Kyoung

    1999-06-01

    Until now, because we have imported experimental animal from foreign experimental animal corporation, we could have saved money by establishing the quality control of animal in barrier system. In order to improve the quality of animal experiment and efficiency of biomedical study, it is indispensable to control many factors that effect in the experiment. Therefore, it is essential to organize the system of laboratory animal care for enhancing reliability and revivability of experimental results. The purpose of the present investigation was to establish the quality control system of experimental animals that we can provide good quality animals according to the experimental condition of each investigator although the exact quality control system to estimate the infection of bacteria and virus easily remains ill-defined yet. Accordingly, we established the useful quality control system for microbiologic monitoring and environmental monitoring to protect experimental animal from harmful bacteria and virus.

  18. The '3Is' of animal experimentation.

    Science.gov (United States)

    2012-05-29

    Animal experimentation in scientific research is a good thing: important, increasing and often irreplaceable. Careful experimental design and reporting are at least as important as attention to welfare in ensuring that the knowledge we gain justifies using live animals as experimental tools.

  19. Animal experimentation--a personal view.

    Science.gov (United States)

    Gershoff, Stanley N

    2009-02-01

    Disagreement about the use of animals in biomedical research has resulted in absurd positions by both sides. Increasingly, some zealots against animal experimentation have resorted to violence or other illegal acts to support their points of view. The value of animal research in providing better health for man and animals is incontrovertible. This is illustrated by references to animal research in the field of nutrition.

  20. [Alternatives to animal experimentation v.s. animal rights terrorism].

    Science.gov (United States)

    Kurosawa, Tsutomu Miki

    2008-05-01

    Systematic modern animal experimentation was established by Bernard Claude who wrote "An Introduction to the Study of Experimental Medicine" in 1865. At this point, the public was already asking that the pain and distress of experimental animals be reduced. For this, scientists, William Russell and Rex Burch in 1959 proposed the principles of alternatives to animal experimentation, the "3Rs". Since that time, animal welfare advocates have promoted the 3Rs concept in biomedical research communities. However, cruel animal experiments have continued and there are reports of radical extremists showing their opposition by invasion, arson, theft and even bombing of institutions involved, resulting in killing of the animals. SHAC, one extremist group believed to be animal welfare activitists was recognized as a terrorist group after the 9.11 tragedy in USA and the government viewed their activities very seriously. In 2001, British animal extremists invaded Japanese universities and stole laboratory resources; one individual was arrested and sentenced to prison for three years; Japanese who assisted in the incident were arrested and one was sentenced for one year. In 2006, SHAC USA members were prosecuted and sentenced for up to 6 years for their terrorism activities including arson. We need to consider the background of these activities which are financially supported by animal welfare advocates. The way we, as scientists who conduct such experiments can respond is by promoting alternatives to this experimentation. In Japan, the animal welfare law was revised in 2005 stressing the importance of 3Rs in scientific activities with animals. The promotion of 3Rs should be strengthened in the pharmaceutical community.

  1. [Contribution of animal experimentation to pharmacology].

    Science.gov (United States)

    Sassard, Jean; Hamon, Michel; Galibert, Francis

    2009-11-01

    Animal experimentation is of considerable importance in pharmacology and cannot yet be avoided when studying complex, highly integrated physiological functions. The use of animals has been drastically reduced in the classical phases of pharmacological research, for example when comparing several compounds belonging to the same pharmacological class. However, animal experiments remain crucial for generating and validating new therapeutic concepts. Three examples of such research, conducted in strict ethical conditions, will be used to illustrate the different ways in which animal experimentation has contributed to human therapeutics.

  2. Animal Experimentation: Issues for the 1980s.

    Science.gov (United States)

    Zola, Judith C.; And Others

    1984-01-01

    Examines the extent to which issues related to animal experimentation are in conflict and proposes choices that might least comprise them. These issues include animal well-being, human well-being, self-interest of science, scientific validity and responsibility, progress in biomedical and behavioral science, and the future quality of medical care.…

  3. [Animal experimentation, computer simulation and surgical research].

    Science.gov (United States)

    Carpentier, Alain

    2009-11-01

    We live in a digital world In medicine, computers are providing new tools for data collection, imaging, and treatment. During research and development of complex technologies and devices such as artificial hearts, computer simulation can provide more reliable information than experimentation on large animals. In these specific settings, animal experimentation should serve more to validate computer models of complex devices than to demonstrate their reliability.

  4. Refining animal experiments: the first Brazilian regulation on animal experimentation.

    Science.gov (United States)

    de A e Tréz, Thales

    2010-06-01

    The very first law on animal experimentation has been approved recently in Brazil, and now is part of a set of the legal instruments that profile the Brazilian government's attitude toward the use of animals in experiments. Law 11794/08 establishes a new legal instrument that will guide new methods of conduct for ethics committees, researchers and representatives of animal protection societies. This comment aims to analyse critically the implications that this law brings to Brazilian reality. The link between it and the Russell and Burch's Three Rs concept is defined, and certain problems are identified. The conclusion is that the body of the law emphasises the refinement of animal experiments, but gives little importance to the principles of reduction and replacement.

  5. Fantastic animals as an experimental model to teach animal adaptation

    Directory of Open Access Journals (Sweden)

    Veronesi Paola

    2007-08-01

    Full Text Available Abstract Background Science curricula and teachers should emphasize evolution in a manner commensurate with its importance as a unifying concept in science. The concept of adaptation represents a first step to understand the results of natural selection. We settled an experimental project of alternative didactic to improve knowledge of organism adaptation. Students were involved and stimulated in learning processes by creative activities. To set adaptation in a historic frame, fossil records as evidence of past life and evolution were considered. Results The experimental project is schematized in nine phases: review of previous knowledge; lesson on fossils; lesson on fantastic animals; planning an imaginary world; creation of an imaginary animal; revision of the imaginary animals; adaptations of real animals; adaptations of fossil animals; and public exposition. A rubric to evaluate the student's performances is reported. The project involved professors and students of the University of Modena and Reggio Emilia and of the "G. Marconi" Secondary School of First Degree (Modena, Italy. Conclusion The educational objectives of the project are in line with the National Indications of the Italian Ministry of Public Instruction: knowledge of the characteristics of living beings, the meanings of the term "adaptation", the meaning of fossils, the definition of ecosystem, and the particularity of the different biomes. At the end of the project, students will be able to grasp particular adaptations of real organisms and to deduce information about the environment in which the organism evolved. This project allows students to review previous knowledge and to form their personalities.

  6. Fantastic animals as an experimental model to teach animal adaptation

    Science.gov (United States)

    Guidetti, Roberto; Baraldi, Laura; Calzolai, Caterina; Pini, Lorenza; Veronesi, Paola; Pederzoli, Aurora

    2007-01-01

    Background Science curricula and teachers should emphasize evolution in a manner commensurate with its importance as a unifying concept in science. The concept of adaptation represents a first step to understand the results of natural selection. We settled an experimental project of alternative didactic to improve knowledge of organism adaptation. Students were involved and stimulated in learning processes by creative activities. To set adaptation in a historic frame, fossil records as evidence of past life and evolution were considered. Results The experimental project is schematized in nine phases: review of previous knowledge; lesson on fossils; lesson on fantastic animals; planning an imaginary world; creation of an imaginary animal; revision of the imaginary animals; adaptations of real animals; adaptations of fossil animals; and public exposition. A rubric to evaluate the student's performances is reported. The project involved professors and students of the University of Modena and Reggio Emilia and of the "G. Marconi" Secondary School of First Degree (Modena, Italy). Conclusion The educational objectives of the project are in line with the National Indications of the Italian Ministry of Public Instruction: knowledge of the characteristics of living beings, the meanings of the term "adaptation", the meaning of fossils, the definition of ecosystem, and the particularity of the different biomes. At the end of the project, students will be able to grasp particular adaptations of real organisms and to deduce information about the environment in which the organism evolved. This project allows students to review previous knowledge and to form their personalities. PMID:17767729

  7. Public perceptions of animal experimentation across Europe.

    Science.gov (United States)

    von Roten, Fabienne Crettaz

    2013-08-01

    The goal of this article is to map out public perceptions of animal experimentation in 28 European countries. Postulating cross-cultural differences, this study mixes country-level variables (from the Eurostat database) and individual-level variables (from Eurobarometer Science and Technology 2010). It is shown that experimentation on animals such as mice is generally accepted in European countries, but perceptions are divided on dogs and monkeys. Between 2005 and 2010, we observe globally a change of approval on dogs and monkeys, with a significant decrease in nine countries. Multilevel analysis results show differences at country level (related to a post-industrialism model) and at individual level (related to gender, age, education, proximity and perceptions of science and the environment). These results may have consequences for public perceptions of science and we call for more cross-cultural research on press coverage of animal research and on the level of public engagement of scientists doing animal research.

  8. Instrumental and ethical aspects of experimental research with animal models

    Directory of Open Access Journals (Sweden)

    Mirian Watanabe

    2014-02-01

    Full Text Available Experimental animal models offer possibilities of physiology knowledge, pathogenesis of disease and action of drugs that are directly related to quality nursing care. This integrative review describes the current state of the instrumental and ethical aspects of experimental research with animal models, including the main recommendations of ethics committees that focus on animal welfare and raises questions about the impact of their findings in nursing care. Data show that, in Brazil, the progress in ethics for the use of animals for scientific purposes was consolidated with Law No. 11.794/2008 establishing ethical procedures, attending health, genetic and experimental parameters. The application of ethics in handling of animals for scientific and educational purposes and obtaining consistent and quality data brings unquestionable contributions to the nurse, as they offer subsidies to relate pathophysiological mechanisms and the clinical aspect on the patient.

  9. Characterization of experimental dental research using animals

    Directory of Open Access Journals (Sweden)

    Ana Flávia Granville-Garcia

    2009-01-01

    Full Text Available Objective: To determine the profile of experimental dental research using animals. Methods: The research comprised all the 4141 abstracts existent in the books of annals from the 22nd and 23rd Annual meetings of the Brazilian Society of Dentistry Research and the sample was composed of 377 studies (9.1%. The variables analyzed were: area of knowledge, type of institution, State of the country, type of animal and body part used, occurrence of animal sacrifice, mention of the Research Ethics Committee, receipt of funding and type of financing agency. Results: The largest number of studies concentrated on the areas of Buccomaxillofacial Surgery (27.3% and Basic Sciences (21.2%. The Public Universities were responsible for 74% of the researches, and the State Institutions were outstanding (82.4%. The State of São Paulo was responsible for 74.1% of the studies. Rats (67.1% and rabbits (11.1% were the most frequently used animals, and 68.2% of the animals were sacrificed. The oral cavity was used in 50.1% of the researches and the mandible in 59%. Only 1.9% of the studies mentioned the Research Ethics Committee and 26.3% reported that they received funding. Conclusion: In Dentistry, studies involving animals are predominant in the areas of buccomaxillofacial surgery and basic sciences, with rats andrabbits being most frequently used. A significant number of guinea pigs are sacrificed during or at the end of the experiments.

  10. Animal experimentation in forensic sciences: How far have we come?

    Science.gov (United States)

    Cattaneo, C; Maderna, E; Rendinelli, A; Gibelli, D

    2015-09-01

    In the third millennium where ethical, ethological and cultural evolution seem to be leading more and more towards an inter-species society, the issue of animal experimentation is a moral dilemma. Speaking from a self-interested human perspective, avoiding all animal testing where human disease and therapy are concerned may be very difficult or even impossible; such testing may not be so easily justifiable when suffering-or killing-of non human animals is inflicted for forensic research. In order to verify how forensic scientists are evolving in this ethical issue, we undertook a systematic review of the current literature. We investigated the frequency of animal experimentation in forensic studies in the past 15 years and trends in publication in the main forensic science journals. Types of species, lesions inflicted, manner of sedation or anesthesia and euthanasia were examined in a total of 404 articles reviewed, among which 279 (69.1%) concerned studies involving animals sacrificed exclusively for the sake of the experiment. Killing still frequently includes painful methods such as blunt trauma, electrocution, mechanical asphyxia, hypothermia, and even exsanguination; of all these animals, apparently only 60.8% were anesthetized. The most recent call for a severe reduction if not a total halt to the use of animals in forensic sciences was made by Bernard Knight in 1992. In fact the principle of reduction and replacement, frequently respected in clinical research, must be considered the basis for forensic science research needing animals. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  11. Experimental animal modelling for TB vaccine development

    Directory of Open Access Journals (Sweden)

    Pere-Joan Cardona

    2017-03-01

    Full Text Available Research for a novel vaccine to prevent tuberculosis is an urgent medical need. The current vaccine, BCG, has demonstrated a non-homogenous efficacy in humans, but still is the gold standard to be improved upon. In general, the main indicator for testing the potency of new candidates in animal models is the reduction of the bacillary load in the lungs at the acute phase of the infection. Usually, this reduction is similar to that induced by BCG, although in some cases a weak but significant improvement can be detected, but none of candidates are able to prevent establishment of infection. The main characteristics of several laboratory animals are reviewed, reflecting that none are able to simulate the whole characteristics of human tuberculosis. As, so far, no surrogate of protection has been found, it is important to test new candidates in several models in order to generate convincing evidence of efficacy that might be better than that of BCG in humans. It is also important to investigate the use of “in silico” and “ex vivo” models to better understand experimental data and also to try to replace, or at least reduce and refine experimental models in animals.

  12. Environmental enrichment in farm, zoo, companion and experimental animals

    OpenAIRE

    Vučinić Marijana

    2009-01-01

    The paper deals with environmental enrichment for domestic animals at farms, animals in zoos, experimental animals and pet animals. Also, the paper defines and describes different strategies of environmental enrichment. Environmental enrichment is a simple and effective mean of prevention of boredom, behavioral disorders as well as an effective mean of improving animal welfare in farm, zoo, companion and experimental animals. Different items and materials may be used for environmental enrichm...

  13. Stereopsis in animals: evolution, function and mechanisms

    Science.gov (United States)

    Read, Jenny C. A.

    2017-01-01

    ABSTRACT Stereopsis is the computation of depth information from views acquired simultaneously from different points in space. For many years, stereopsis was thought to be confined to primates and other mammals with front-facing eyes. However, stereopsis has now been demonstrated in many other animals, including lateral-eyed prey mammals, birds, amphibians and invertebrates. The diversity of animals known to have stereo vision allows us to begin to investigate ideas about its evolution and the underlying selective pressures in different animals. It also further prompts the question of whether all animals have evolved essentially the same algorithms to implement stereopsis. If so, this must be the best way to do stereo vision, and should be implemented by engineers in machine stereopsis. Conversely, if animals have evolved a range of stereo algorithms in response to different pressures, that could inspire novel forms of machine stereopsis appropriate for distinct environments, tasks or constraints. As a first step towards addressing these ideas, we here review our current knowledge of stereo vision in animals, with a view towards outlining common principles about the evolution, function and mechanisms of stereo vision across the animal kingdom. We conclude by outlining avenues for future work, including research into possible new mechanisms of stereo vision, with implications for machine vision and the role of stereopsis in the evolution of camouflage. PMID:28724702

  14. Experimental Oral Candidiasis in Animal Models

    Science.gov (United States)

    Samaranayake, Yuthika H.; Samaranayake, Lakshman P.

    2001-01-01

    Oral candidiasis is as much the final outcome of the vulnerability of the host as of the virulence of the invading organism. We review here the extensive literature on animal experiments mainly appertaining to the host predisposing factors that initiate and perpetuate these infections. The monkey, rat, and mouse are the choice models for investigating oral candidiasis, but comparisons between the same or different models appear difficult, because of variables such as the study design, the number of animals used, their diet, the differences in Candida strains, and the duration of the studies. These variables notwithstanding, the following could be concluded. (i) The primate model is ideal for investigating Candida-associated denture stomatitis since both erythematous and pseudomembranous lesions have been produced in monkeys with prosthetic plates; they are, however, expensive and difficult to obtain and maintain. (ii) The rat model (both Sprague-Dawley and Wistar) is well proven for observing chronic oral candidal colonization and infection, due to the ease of breeding and handling and their ready availability. (iii) Mice are similar, but in addition there are well characterized variants simulating immunologic and genetic abnormalities (e.g., athymic, euthymic, murine-acquired immune deficiency syndrome, and severe combined immunodeficient models) and hence are used for short-term studies relating the host immune response and oral candidiasis. Nonetheless, an ideal, relatively inexpensive model representative of the human oral environment in ecological and microbiological terms is yet to be described. Until such a model is developed, researchers should pay attention to standardization of the experimental protocols described here to obtain broadly comparable and meaningful data. PMID:11292645

  15. Ethics and animal experimentation: what is debated?

    Directory of Open Access Journals (Sweden)

    Paixão Rita Leal

    1999-01-01

    Full Text Available The purpose of this article is to raise some points for an understanding of the contemporary debate over the ethics of using animals in scientific experiments. We present the various positions from scientific and moral perspectives establishing different ways of viewing animals, as well as several concepts like 'animal ethics', 'animal rights', and 'animal welfare'. The paper thus aims to analyze the importance and growth of this debate, while proposing to expand the academic approach to this theme in the field of health.

  16. Ethics and animal experimentation: what is debated?

    Directory of Open Access Journals (Sweden)

    Rita Leal Paixão

    Full Text Available The purpose of this article is to raise some points for an understanding of the contemporary debate over the ethics of using animals in scientific experiments. We present the various positions from scientific and moral perspectives establishing different ways of viewing animals, as well as several concepts like 'animal ethics', 'animal rights', and 'animal welfare'. The paper thus aims to analyze the importance and growth of this debate, while proposing to expand the academic approach to this theme in the field of health.

  17. The flaws and human harms of animal experimentation.

    Science.gov (United States)

    Akhtar, Aysha

    2015-10-01

    Nonhuman animal ("animal") experimentation is typically defended by arguments that it is reliable, that animals provide sufficiently good models of human biology and diseases to yield relevant information, and that, consequently, its use provides major human health benefits. I demonstrate that a growing body of scientific literature critically assessing the validity of animal experimentation generally (and animal modeling specifically) raises important concerns about its reliability and predictive value for human outcomes and for understanding human physiology. The unreliability of animal experimentation across a wide range of areas undermines scientific arguments in favor of the practice. Additionally, I show how animal experimentation often significantly harms humans through misleading safety studies, potential abandonment of effective therapeutics, and direction of resources away from more effective testing methods. The resulting evidence suggests that the collective harms and costs to humans from animal experimentation outweigh potential benefits and that resources would be better invested in developing human-based testing methods.

  18. Animal experimentation-Part II: In periodontal research

    Directory of Open Access Journals (Sweden)

    T K Pal

    2015-01-01

    Full Text Available Animals contribute to the development of medical and dental sciences by being sacrificed in the hands of scientists. The experimental design demands a specific type of animal to be used for experimentation. Each animal needs proper handling, care, and diet. Alongside specific advantages and disadvantages pertaining to each type of animal need to be understood well depending on the type of study/experiment. It is important for the researcher to know the disease susceptibility of each animal. The purpose of this paper is to highlight the salient factors that need to be considered for animal experimentations.

  19. Basic mechanisms of MCD in animal models.

    Science.gov (United States)

    Battaglia, Giorgio; Becker, Albert J; LoTurco, Joseph; Represa, Alfonso; Baraban, Scott C; Roper, Steven N; Vezzani, Annamaria

    2009-09-01

    Epilepsy-associated glioneuronal malformations (malformations of cortical development [MCD]) include focal cortical dysplasias (FCD) and highly differentiated glioneuronal tumors, most frequently gangliogliomas. The neuropathological findings are variable but suggest aberrant proliferation, migration, and differentiation of neural precursor cells as essential pathogenetic elements. Recent advances in animal models for MCDs allow new insights in the molecular pathogenesis of these epilepsy-associated lesions. Novel approaches, presented here, comprise RNA interference strategies to generate and study experimental models of subcortical band heterotopia and study functional aspects of aberrantly shaped and positioned neurons. Exciting analyses address impaired NMDA receptor expression in FCD animal models compared to human FCDs and excitatory imbalances in MCD animal models such as lissencephaly gene ablated mice as well as in utero irradiated rats. An improved understanding of relevant pathomechanisms will advance the development of targeted treatment strategies for epilepsy-associated malformations.

  20. Inflammation-induced preterm lung maturation: lessons from animal experimentation.

    Science.gov (United States)

    Moss, Timothy J M; Westover, Alana J

    2017-06-01

    Intrauterine inflammation, or chorioamnionitis, is a major contributor to preterm birth. Prematurity per se is associated with considerable morbidity and mortality resulting from lung immaturity but exposure to chorioamnionitis reduces the risk of neonatal respiratory distress syndrome (RDS) in preterm infants. Animal experiments have identified that an increase in pulmonary surfactant production by the preterm lungs likely underlies this decreased risk of RDS in infants exposed to chorioamnionitis. Further animal experimentation has shown that infectious or inflammatory agents in amniotic fluid exert their effects on lung development by direct effects within the developing respiratory tract, and probably not by systemic pathways. Differences in the effects of intrauterine inflammation and glucocorticoids demonstrate that canonical glucocorticoid-mediated lung maturation is not responsible for inflammation-induced changes in lung development. Animal experimentation is identifying alternative lung maturational pathways, and transgenic animals and cell culture techniques will allow identification of novel mechanisms of lung maturation that may lead to new treatments for the prevention of RDS. Copyright © 2016. Published by Elsevier Ltd.

  1. Animal experimentations: Part I: General considerations

    Directory of Open Access Journals (Sweden)

    T K Pal

    2015-01-01

    Full Text Available All materials, in the form of drugs or devices, which are intended for human use are required to be tested first in suitable animals. Many biological understandings are established on various modes of cruelties on animals. This observational notes guide us to accept or modify or even reject materials for ultimate human use. The science of experiments on animals gives us the remedial solutions to many of our human sufferings. This unique and important discipline is in need of proper understanding for selection of suitable number of animals and its proper care in captivity, and further refinements of code of conducts and ethical issues.

  2. Prevention of occupational risks in animal experimentation

    International Nuclear Information System (INIS)

    Martinez Palacio, J.

    2007-01-01

    This work focuses on the main specific risks for those working with laboratory animals in a Research Center such as CIEMAT. First we present the general biological risks, their laws and rules. Next, we development the specific risks associated with the laboratory animals, zoonotic diseases and allergies. then we deal with the risks that can be consequence of working with laboratory animals, ionizing radiations, chemical products, genetically modified organisms, liquid nitrogen management, bio containment and human samples management. As they are subjects of interest, we also include the workers health assesment for those exposed to biological agents, including recommendations about hygiene and disinfections. (Author)

  3. Experimental animal data and modeling of late somatic effects

    International Nuclear Information System (INIS)

    Fry, R.J.M.

    1988-01-01

    This section is restricted to radiation-induced life shortening and cancer and mainly to studies with external radiation. The emphasis will be on the experimental data that are available and the experimental systems that could provide the type of data with which to either formulate or test models. Genetic effects which are of concern are not discussed in this section. Experimental animal radiation studies fall into those that establish general principles and those that demonstrate mechanisms. General principles include the influence of dose, radiation quality, dose rate, fractionation, protraction and such biological factors as age and gender. The influence of these factors are considered as general principles because they are independent, at least qualitatively, of the species studied. For example, if an increase in the LET of the radiation causes an increased effectiveness in cancer induction in a mouse a comparable increase in effectiveness can be expected in humans. Thus, models, whether empirical or mechanistic, formulated from experimental animal data should be generally applicable

  4. Criticizing animal experimentation, at my peril.

    Science.gov (United States)

    Eisenman, Stephen F

    2016-01-01

    Initiatives leading to even modest reduction in animal use at major U.S. universities are likely to continue to face strong opposition. At least, that's the conclusion the author draws from his efforts at Northwestern University. In fact, despite a growing body of evidence that animal-based research is flawed at best and misleading or un-scientific at worst its use is growing at Northwestern and elsewhere. Moreover, recent discoveries concerning animal consciousness and emotion have not led to notable improvements in the conditions in which AWA protected animals live at the Chicago vivarium. There, animals languish in featureless rooms or sterile cages without access to daylight and with little opportunity to express their natural behaviors and aptitudes. The writer's public exposure of these conditions led to a fierce backlash. Unless there is a significant change in laboratory and university culture, change will only come when the marketplace and funding agencies demand better and more reliable, non-animal models for the testing of drug toxicity and effectiveness.

  5. Biological effects of transuranium elements in experimental animals

    International Nuclear Information System (INIS)

    Bair, W.J.

    1975-01-01

    Results are reported from life span studies of the biological effects of the transuranium elements ( 238 Pu, 239 Pu, 241 Am, and 242 Cm) on laboratory animals following inhalation, skin absorption, or injection in various chemical forms. The dose levels at which major biological effects have been observed in experimental animals are discussed relative to the maximum permissible lung burden of 0.016 μCi for occupational exposures. Lung cancer has been observed at dose levels equivalent to about 100 times the maximum permissible lung burden. Current experiments directed towards determining whether health effects will occur at lower levels and the mechanisms by which α emitters induce cancer are reviewed. (U.S.)

  6. Computational Design of Animated Mechanical Characters

    Science.gov (United States)

    Coros, Stelian; Thomaszewski, Bernhard; DRZ Team Team

    2014-03-01

    A factor key to the appeal of modern CG movies and video-games is that the virtual worlds they portray place no bounds on what can be imagined. Rapid manufacturing devices hold the promise of bringing this type of freedom to our own world, by enabling the fabrication of physical objects whose appearance, deformation behaviors and motions can be precisely specified. In order to unleash the full potential of this technology however, computational design methods that create digital content suitable for fabrication need to be developed. In recent work, we presented a computational design system that allows casual users to create animated mechanical characters. Given an articulated character as input, the user designs the animated character by sketching motion curves indicating how they should move. For each motion curve, our framework creates an optimized mechanism that reproduces it as closely as possible. The resulting mechanisms are attached to the character and then connected to each other using gear trains, which are created in a semi-automated fashion. The mechanical assemblies generated with our system can be driven with a single input driver, such as a hand-operated crank or an electric motor, and they can be fabricated using rapid prototyping devices.

  7. Alternatives to animal experimentation in basic research.

    Science.gov (United States)

    Gruber, Franz P; Hartung, Thomas

    2004-01-01

    In contrast to animal testing required by law to guarantee minimum safety standards for the licensing of drugs and chemicals, there are no regulations in basic research forcing scientists to perform animal tests. By (usually) free choice, questions are posed and hypotheses are examined which, in many cases, can only be answered by means of animal tests. Just as easily, different questions could be asked or different hypotheses could be examined which do not require animal tests. The only criterion for the choice of a topic is its relevance which cannot necessarily be judged in the short-term. Thus, it is up to the individual scientist to judge what is worth studying and therefore worth animal consumption. The educated mind will consider ethical aspects of this choice. However, on the other hand, this decision is largely influenced by questions of efficacy or (in a negative sense) by the obstacles posed to an animal consuming approach. Here, peer review and general attitude will strongly influence the methodology chosen. Availability and awareness of adequate in vitro techniques represent the prerequisites for the use of alternative methods. The least one can do in basic research is to avoid tests which cause severe suffering to animals, as is required in Switzerland and other European countries by binding ethical principles and guidelines. The increasing standard of approval and control procedures has improved the situation over the years. There are many examples of successful alternative methods in basic research. But, the application of such methods is in most cases limited to the laboratories in which they were developed, calling for technology transfer. Exceptions are procedures that are used worldwide, like the production of monoclonal antibodies, which instead of using the ascites mouse can also be performed in vitro with some good will. In these cases, commercialisation of the techniques has aided their spread within the scientific community. Sadly, many

  8. The animal experimentation controversy: Ethical views of ...

    African Journals Online (AJOL)

    ... and scientific research. The responses were analysed qualitatively and quantitatively. The results showed that most prospective teachers are in favour of animal rights and that females are more averse to vivisection than males. A number of suggestions are made with regard to vivisection in schools and tertiary institutions.

  9. Animal Experimentation: Bringing Ethical Issues into Biology Teaching.

    Science.gov (United States)

    Van Rooy, Wilhelmina

    2000-01-01

    There are many possibilities for the use of controversial issues such as animal experimentation in biology classrooms. Outlines a series of three lessons that asked senior biology students to consider the issue of animal experimentation from three perspectives. (Author/LM)

  10. Ethics of animal research in human disease remediation, its institutional teaching; and alternatives to animal experimentation.

    Science.gov (United States)

    Cheluvappa, Rajkumar; Scowen, Paul; Eri, Rajaraman

    2017-08-01

    Animals have been used in research and teaching for a long time. However, clear ethical guidelines and pertinent legislation were instated only in the past few decades, even in developed countries with Judeo-Christian ethical roots. We compactly cover the basics of animal research ethics, ethical reviewing and compliance guidelines for animal experimentation across the developed world, "our" fundamentals of institutional animal research ethics teaching, and emerging alternatives to animal research. This treatise was meticulously constructed for scientists interested/involved in animal research. Herein, we discuss key animal ethics principles - Replacement/Reduction/Refinement. Despite similar undergirding principles across developed countries, ethical reviewing and compliance guidelines for animal experimentation vary. The chronology and evolution of mandatory institutional ethical reviewing of animal experimentation (in its pioneering nations) are summarised. This is followed by a concise rendition of the fundamentals of teaching animal research ethics in institutions. With the advent of newer methodologies in human cell-culturing, novel/emerging methods aim to minimise, if not avoid the usage of animals in experimentation. Relevant to this, we discuss key extant/emerging alternatives to animal use in research; including organs on chips, human-derived three-dimensional tissue models, human blood derivates, microdosing, and computer modelling of various hues. © 2017 The Authors. Pharmacology Research & Perspectives published by John Wiley & Sons Ltd, British Pharmacological Society and American Society for Pharmacology and Experimental Therapeutics.

  11. Alternatives to animal experimentation: The regulatory background

    International Nuclear Information System (INIS)

    Garthoff, Bernward

    2005-01-01

    The framework, in which alternatives to animal experiments can be developed, standardized, respectively formally validated, has to be seen in a global context. The ever increasing demand of testing for hazard and risk assessment in health and environment, exemplified by the EU REACH program, subsequently triggers laboratory animal testing. This holds especially true, if no valid alternative methods agreed to by the regulatory authorities and the scientific community are available. At least for regulatory toxicity testing, the global frame and network are given by institutions such as OECD, ICH, and alike. However, due to the necessity of global consent of states, organizations, and stakeholders, the time gap between availability of a novel alternative test method and its final acceptance by authorities and implementation thereafter is widening. The lack of new technologies or opportunities for alternative method application such as, for example, the broad use of transgenic animals for refinement of existing tests, adds to the problem. The bare existence of certain in vivo tests increases also the gap between public demands for testing versus availability of alternative tests. Industries operating on a worldwide basis support the alternative test development in their respective area of research and operational business. However, a more coordinating approach such as that of the ecopa-organization (European Consensus Platform on Alternatives) is needed to exploit the existing possibilities within the current regulatory framework. This will speed up the process of acceptance and challenge the political worldto feel responsible for the sequels of their demanding more testing, that is, by funding alternative method development in academia and industry

  12. Immune mechanisms in Babesia-infected animals

    International Nuclear Information System (INIS)

    Phillips, R.S.

    1980-01-01

    The course of a Babesia infection depends on the species of host and parasite involved. Animals infected with virulent babesias may need chemotherapy before acquired immunity develops. Maintenance of immunity is not dependent on the presence of the parasite. Babesia infections are characteristically of long duration. The immune response to babesias includes both humoral and cellular components. Antibody levels detected in serodiagnostic tests do not relate to levels of resistance to the parasite. Some antibodies, however, appear to be protective. Antiparasitic antibodies may damage parasites in or outside the red cell and act as opsonins. T-cell-deficient and anti-lymphocyte-serum-treated rodents are more susceptible to rodent piroplasms indicating a role for T-cells as either helper cells and/or as mediators of cell-mediated immunity (CMI). There is indirect evidence of CMI, but the cell-mediated mechanisms involved in parasite killing are not known. In domestic animals immunity is largely species- and strain-specific. Antigenic variation by babesias occurs. In rodents, however, there is cross-immunity between different species of rodent piroplasms and between rodent piroplasms and some malaria parasites. Prior infection with agents such as BCG, and Corynebacterium parvum, gives mice non-specific resistance to rodent piroplasms possibly mediated through a soluble non-antibody factor. This factor may also be liberated during piroplasm infections and by being toxic to malaria parasites account for heterologous immunity. Active immunization against babesias has been achieved with avirulent strains, irradiated parasites and dead parasites in adjuvant. During Babesia infections the primary and, to a lesser degree, the secondary immune response to heterologous antigens can be depressed. Maximum depression coincides with peak parasitaemia when antigen priming may be abolished completely. Immunosuppression during Babesia infections can prolong or exacerbate concurrent

  13. Physiological mechanisms underlying animal social behaviour.

    Science.gov (United States)

    Seebacher, Frank; Krause, Jens

    2017-08-19

    Many species of animal live in groups, and the group represents the organizational level within which ecological and evolutionary processes occur. Understanding these processes, therefore, relies on knowledge of the mechanisms that permit or constrain group formation. We suggest that physiological capacities and differences in physiology between individuals modify fission-fusion dynamics. Differences between individuals in locomotor capacity and metabolism may lead to fission of groups and sorting of individuals into groups with similar physiological phenotypes. Environmental impacts such as hypoxia can influence maximum group sizes and structure in fish schools by altering access to oxygenated water. The nutritional environment determines group cohesion, and the increase in information collected by the group means that individuals should rely more on social information and form more cohesive groups in uncertain environments. Changing environmental contexts require rapid responses by individuals to maintain group coordination, which are mediated by neuroendocrine signalling systems such as nonapeptides and steroid hormones. Brain processing capacity may constrain social complexity by limiting information processing. Failure to evaluate socially relevant information correctly limits social interactions, which is seen, for example, in autism. Hence, functioning of a group relies to a large extent on the perception and appropriate processing of signals from conspecifics. Many if not all physiological systems are mechanistically linked, and therefore have synergistic effects on social behaviour. A challenge for the future lies in understanding these interactive effects, which will improve understanding of group dynamics, particularly in changing environments.This article is part of the themed issue 'Physiological determinants of social behaviour in animals'. © 2017 The Author(s).

  14. A device for external γ-irradiation of experimental animals

    International Nuclear Information System (INIS)

    Ivanitskaya, N.F.; Talakin, Yu.N.; Lekakh, V.A.

    1992-01-01

    A device was developed for external gamma-irradiation of experimental animals including a radiation source, a device for fixation of the total animal or a segment of its body in the focus of irradiation, and a shilding screen. To widen the sphere of this device application by making possible a simultaneous radiation exposure of a group of animals under various radiation schedules, the device involves two discs with a common axis. The lower disc is provided with an electric drive and containers with animals are placed on it, and the upper disc is for the shielding screen. The device is supplied with an operation block

  15. [The 1, 2, 3 of laboratory animal experimentation].

    Science.gov (United States)

    Romero-Fernandez, Wilber; Batista-Castro, Zenia; De Lucca, Marisel; Ruano, Ana; García-Barceló, María; Rivera-Cervantes, Marta; García-Rodríguez, Julio; Sánchez-Mateos, Soledad

    2016-06-01

    The slow scientific development in Latin America in recent decades has delayed the incorporation of laboratory animal experimentation; however, this situation has started to change. Today, extraordinary scientific progress is evident, which has promoted the introduction and increased use of laboratory animals as an important tool for the advancement of biomedical sciences. In the aftermath of this boom, the need to provide the scientific community with training and guidance in all aspects related to animal experimentation has arisen. It is the responsibility of each country to regulate this practice, for both bioethical and legal reasons, to ensure consideration of the animals' rights and welfare. The following manuscript is the result of papers presented at the International Workshop on Laboratory Animal Testing held at the Technical University of Ambato, Ecuador; it contains information regarding the current state of affairs in laboratory animal testing and emphasizes critical aspects such as main species used, ethical and legal principles, and experimental and alternative designs for animal use. These works aim to ensure good practices that should define scientific work. This document will be relevant to both researchers who aim to newly incorporate animal testing into their research and those who seek to update their knowledge.

  16. [Reduction of animal experiments in experimental drug testing].

    Science.gov (United States)

    Behrensdorf-Nicol, H; Krämer, B

    2014-10-01

    In order to ensure the quality of biomedical products, an experimental test for every single manufactured batch is required for many products. Especially in vaccine testing, animal experiments are traditionally used for this purpose. For example, efficacy is often determined via challenge experiments in laboratory animals. Safety tests of vaccine batches are also mostly performed using laboratory animals. However, many animal experiments have clear inherent disadvantages (low accuracy, questionable transferability to humans, unclear significance). Furthermore, for ethical reasons and animal welfare aspects animal experiments are also seen very critical by the public. Therefore, there is a strong trend towards replacing animal experiments with methods in which no animals are used ("replacement"). If a replacement is not possible, the required animal experiments should be improved in order to minimize the number of animals necessary ("reduction") and to reduce pain and suffering caused by the experiment to a minimum ("refinement"). This "3R concept" is meanwhile firmly established in legislature. In recent years many mandatory animal experiments have been replaced by alternative in vitro methods or improved according to the 3R principles; numerous alternative methods are currently under development. Nevertheless, the process from the development of a new method to its legal implementation takes a long time. Therefore, supplementary regulatory measures to facilitate validation and acceptance of new alternative methods could contribute to a faster and more consequent implementation of the 3R concept in the testing of biomedical products.

  17. Developing and Evaluating Animations for Teaching Quantum Mechanics Concepts

    Science.gov (United States)

    Kohnle, Antje; Douglass, Margaret; Edwards, Tom J.; Gillies, Alastair D.; Hooley, Christopher A.; Sinclair, Bruce D.

    2010-01-01

    In this paper, we describe animations and animated visualizations for introductory and intermediate-level quantum mechanics instruction developed at the University of St Andrews. The animations aim to help students build mental representations of quantum mechanics concepts. They focus on known areas of student difficulty and misconceptions by…

  18. [Animal experimentation in the discovery and production of veterinary vaccines].

    Science.gov (United States)

    Audonnet, J Ch; Lechenet, J; Verschuere, B

    2007-08-01

    Veterinary vaccine research, development and production facilities must aim to improve animal welfare, respond to public concerns and meet regulatory requirements, while at the same time fulfilling their objective of producing evermore effective and safer vaccines. The use of animal experimentation for the development of new veterinary vaccines is inevitable, as no in vitro model can predict a candidate vaccine's ability to induce protection in the target species. Against the backdrop of ethical and regulatory constraints, constant progress is being made in creating the best possible conditions for animal experimentation. Keeping up to date with the constant changes in the field of animal ethics requires a particular effort on the part of the pharmaceutical industry, which must make careful changes to product registration documentation in accordance with each new development.

  19. Systematic heterogenization for better reproducibility in animal experimentation.

    Science.gov (United States)

    Richter, S Helene

    2017-08-31

    The scientific literature is full of articles discussing poor reproducibility of findings from animal experiments as well as failures to translate results from preclinical animal studies to clinical trials in humans. Critics even go so far as to talk about a "reproducibility crisis" in the life sciences, a novel headword that increasingly finds its way into numerous high-impact journals. Viewed from a cynical perspective, Fett's law of the lab "Never replicate a successful experiment" has thus taken on a completely new meaning. So far, poor reproducibility and translational failures in animal experimentation have mostly been attributed to biased animal data, methodological pitfalls, current publication ethics and animal welfare constraints. More recently, the concept of standardization has also been identified as a potential source of these problems. By reducing within-experiment variation, rigorous standardization regimes limit the inference to the specific experimental conditions. In this way, however, individual phenotypic plasticity is largely neglected, resulting in statistically significant but possibly irrelevant findings that are not reproducible under slightly different conditions. By contrast, systematic heterogenization has been proposed as a concept to improve representativeness of study populations, contributing to improved external validity and hence improved reproducibility. While some first heterogenization studies are indeed very promising, it is still not clear how this approach can be transferred into practice in a logistically feasible and effective way. Thus, further research is needed to explore different heterogenization strategies as well as alternative routes toward better reproducibility in animal experimentation.

  20. Science and society: different bioethical approaches towards animal experimentation.

    Science.gov (United States)

    Brom, Frans W A

    2002-01-01

    respect their integrity. By weighing these prima facie duties, the moral problem of animal experimentation exists in finding which duty actually has to be considered as the decisive duty. It will be argued that these three views, even though they will all justify animal experimentation to some extent, will do so in practice under different conditions. Many current conflicts regarding the use of animals for research may be better understood in light of the conflict between the three bioethical perspectives provided by these views.

  1. Stereopsis in animals: evolution, function and mechanisms

    OpenAIRE

    Nityananda, Vivek; Read, Jenny C. A.

    2017-01-01

    ABSTRACT Stereopsis is the computation of depth information from views acquired simultaneously from different points in space. For many years, stereopsis was thought to be confined to primates and other mammals with front-facing eyes. However, stereopsis has now been demonstrated in many other animals, including lateral-eyed prey mammals, birds, amphibians and invertebrates. The diversity of animals known to have stereo vision allows us to begin to investigate ideas about its evolution and th...

  2. [A NEW APPROACH FOR FOOD PREFERENCE TESTING IN ANIMAL EXPERIMENTATION].

    Science.gov (United States)

    Albertin, S V

    2015-10-01

    An article describes the original method allowing to study a mechanism of food preference related to the sensory properties of foods in animals. The method gives a good possibility to select the role of visual and orosensory signaling in food preference as well as to model the processes of physiological and pathological food and drug dependence in animal experiments. The role of discrete food presentation in the formation of the current motivations and food preferences was discussed.

  3. Hepatoprotective activity of Amaranthus spinosus in experimental animals.

    Science.gov (United States)

    Zeashan, Hussain; Amresh, G; Singh, Satyawan; Rao, Chandana Venkateswara

    2008-11-01

    The hepatoprotective and antioxidant activity of 50% ethanolic extract of whole plant of Amaranthus spinosus (ASE) was evaluated against carbon tetrachloride (CCl4) induced hepatic damage in rats. The ASE at dose of 100, 200 and 400 mg/kg were administered orally once daily for fourteen days. The substantially elevated serum enzymatic levels of serum glutamate oxaloacetate transaminase (AST), serum glutamate pyruvate transaminase (ALT), serum alkaline phosphatase (SALP) and total bilirubin were restored towards normalization significantly by the ASE in a dose dependent manner. Higher dose exhibited significant hepatoprotective activity against carbon tetrachloride induced hepatotoxicity in rats. The biochemical observations were supplemented with histopathological examination of rat liver sections. Meanwhile, in vivo antioxidant activities as malondialdehyde (MDA), hydroperoxides, reduced glutathione (GSH), superoxide dismutase (SOD) and catalase (CAT) were also screened which were also found significantly positive in a dose dependent manner. The results of this study strongly indicate that whole plants of A. spinosus have potent hepatoprotective activity against carbon tetrachloride induced hepatic damage in experimental animals. This study suggests that possible mechanism of this activity may be due to the presence of flavonoids and phenolics compound in the ASE which may be responsible to hepatoprotective activity.

  4. The Animal Experimentation Controversy: Ethical Views of Prospective Teachers

    Science.gov (United States)

    de Villiers, Rian

    2012-01-01

    Vivisection (live animal experimentation) is a controversial issue for many people. The purpose of this case study is to examine the attitudes of prospective teachers toward vivisection in education and research, to determine if gender has an influence on these attitudes, and to discuss the implications of these attitudes with regard to teaching…

  5. Checklist of vertebrate animals of the Cascade Head Experimental Forest.

    Science.gov (United States)

    Chris Maser; Jerry F. Franklin

    1974-01-01

    Three months, April and August 1971 and August 1972, were spent studying the vertebrate fauna of Cascade Head Experimental Forest. The resulting annotated checklist includes 9 amphibians, 2 reptiles, 35 birds, and 40 mammals. A standardized animal habitat classification is presented in an effort to correlate the vertebrates in some meaningful way to their environment...

  6. Experimental animal studies of radon and cigarette smoke

    International Nuclear Information System (INIS)

    Cross, F.T.; Dagle, G.E.; Gies, R.A.; Smith, L.G.; Buschbom, R.L.

    1992-01-01

    Cigarette-smoking is a dominant cause of lung cancer and confounds risk assessment of exposure to radon decay products. Evidence in humans on the interaction between cigarette-smoking and exposure to radon decay products, although limited, indicates a possible synergy. Experimental animal data, in addition to showing synergy, also show a decrease or no change in risk with added cigarette-smoke exposures. This article reviews previous animal data developed at Compagnie Generale des Matieres Nucleaires and Pacific Northwest Laboratory (PNL) on mixed exposures to radon and cigarette smoke, and highlights new initiation-promotion-initiation (IPI) studies at PNL that were designed within the framework of a two-mutation carcinogenesis model. Also presented are the PNL exposure system, experimental protocols, dosimetry, and biological data observed to date in IPI animals

  7. Conservation of boundary extension mechanisms between plants and animals

    OpenAIRE

    Mathur, Jaideep

    2005-01-01

    Locomotion clearly sets plants and animals apart. However, recent studies in higher plants reveal cell-biological and molecular features similar to those observed at the leading edge of animal cells and suggest conservation of boundary extension mechanisms between motile animal cells and nonmotile plant cells.

  8. Multivariate Analysis for Animal Selection in Experimental Research

    Directory of Open Access Journals (Sweden)

    Renan Mercuri Pinto

    2015-02-01

    Full Text Available Background: Several researchers seek methods for the selection of homogeneous groups of animals in experimental studies, a fact justified because homogeneity is an indispensable prerequisite for casualization of treatments. The lack of robust methods that comply with statistical and biological principles is the reason why researchers use empirical or subjective methods, influencing their results. Objective: To develop a multivariate statistical model for the selection of a homogeneous group of animals for experimental research and to elaborate a computational package to use it. Methods: The set of echocardiographic data of 115 male Wistar rats with supravalvular aortic stenosis (AoS was used as an example of model development. Initially, the data were standardized, and became dimensionless. Then, the variance matrix of the set was submitted to principal components analysis (PCA, aiming at reducing the parametric space and at retaining the relevant variability. That technique established a new Cartesian system into which the animals were allocated, and finally the confidence region (ellipsoid was built for the profile of the animals’ homogeneous responses. The animals located inside the ellipsoid were considered as belonging to the homogeneous batch; those outside the ellipsoid were considered spurious. Results: The PCA established eight descriptive axes that represented the accumulated variance of the data set in 88.71%. The allocation of the animals in the new system and the construction of the confidence region revealed six spurious animals as compared to the homogeneous batch of 109 animals. Conclusion: The biometric criterion presented proved to be effective, because it considers the animal as a whole, analyzing jointly all parameters measured, in addition to having a small discard rate.

  9. Uterus transplantation: Experimental animal models and recent experience in humans

    Directory of Open Access Journals (Sweden)

    Sadık Şahin

    2015-03-01

    Full Text Available Uterus transplantation has been considered as an alternative management modality in the last few years for adoption or gestational surrogacy for women with absence of uterus due to congenital or acquired reasons. Surrogacy is legal in only a few countries because of ethical, social and legal issues. Up to date, a total of 11 uterus transplantation cases have been reported in which uteri were harvested from ten live donors and one donor with brain death. After unsuccessful attempt of first uterus transplantation, many studies have been conducted in animals and these experimental models enabled our knowledge to increase on this topic. First experimental studies were performed in rodents; later uterus transplantation was accomplished in sheep, pigs and rabbits. Recently, researches in non-human primates have led the experience regarding transplantation technique and success to improve. In this review, we reviewed the experimental animal researches in the area of uterus transplantation and recent experience in humans.

  10. Using Computational and Mechanical Models to Study Animal Locomotion

    Science.gov (United States)

    Miller, Laura A.; Goldman, Daniel I.; Hedrick, Tyson L.; Tytell, Eric D.; Wang, Z. Jane; Yen, Jeannette; Alben, Silas

    2012-01-01

    Recent advances in computational methods have made realistic large-scale simulations of animal locomotion possible. This has resulted in numerous mathematical and computational studies of animal movement through fluids and over substrates with the purpose of better understanding organisms’ performance and improving the design of vehicles moving through air and water and on land. This work has also motivated the development of improved numerical methods and modeling techniques for animal locomotion that is characterized by the interactions of fluids, substrates, and structures. Despite the large body of recent work in this area, the application of mathematical and numerical methods to improve our understanding of organisms in the context of their environment and physiology has remained relatively unexplored. Nature has evolved a wide variety of fascinating mechanisms of locomotion that exploit the properties of complex materials and fluids, but only recently are the mathematical, computational, and robotic tools available to rigorously compare the relative advantages and disadvantages of different methods of locomotion in variable environments. Similarly, advances in computational physiology have only recently allowed investigators to explore how changes at the molecular, cellular, and tissue levels might lead to changes in performance at the organismal level. In this article, we highlight recent examples of how computational, mathematical, and experimental tools can be combined to ultimately answer the questions posed in one of the grand challenges in organismal biology: “Integrating living and physical systems.” PMID:22988026

  11. [For active dermatocosmetics and free of unnecessary animal experimentation].

    Science.gov (United States)

    Piérard, G E; Piérard-Franchimont, C

    1998-06-01

    At the dawn of this century, dermocosmetology is at cross-roads because new European regulations are changing its face. The proof of claims must be given and the entire composition of the product must be released. In addition, animal testing is about to be banned. Such new regulations incite to search for and validate predictive tests aiming at the objective evaluation of the activity and tolerance claimed by dermocosmetic products. Such tests must be an alternative to unnecessary animal experimentation. These aspects are scrutinized scientifically by the EEMCO experts in combination with the ECVAM and COLIPA organizations.

  12. Testing Experimental Compounds against Leishmaniansis in Laboratory Animal Model Systems

    Science.gov (United States)

    1984-09-01

    consulted in five human and two canine cases of suspected leishmaniasis. Two of the 5 human cases were isoenzyme typed as L. b. braziliensis ( Peru ...animal. The latter may be of use in controlling some of the complications of diabetes . %’Wr WF ’ 56 PU BLICAT I ONS_ Griffith, O.W., "Mechanism of

  13. [Origin of animal experimentation legislation in the 19th century].

    Science.gov (United States)

    Pocard, M

    1999-01-01

    The first legislation in the world, designed to protect animals used in research, was passed in England in 1876, and is still in force today. It is one of the strictest in Europe. At the same period, France had no such law, and was the country conducting the greatest amount of animal experimentation. Comparing, these two countries, in the middle of the 19th century, can account for this difference. The most important difference seems to be related to the theological question: are animals endowed with a soul? Saint Augustine, claimed, in the 4th century, perhaps because of an experiment with the centipede, that animals do not have a soul. In the 17th century, René Descartes, using a different philosophical system, reached a similar conclusion, in France. On the other hand, under the influence of Charles Darwin, England rejected the Roman Catholic conclusion, about the soul of animals. The industrial revolution, occurring earlier in England than in France, also changed the society, developing urban areas, where people were cut off from rural life and changing human relationships with animals. The industrial revolution enabled the development of the press, giving impetus to public opinion. These facts, combined with a caution of science, which was more developed in England than in France, brought about the first important "anti-doctor" campaign.

  14. Developing and evaluating animations for teaching quantum mechanics concepts

    International Nuclear Information System (INIS)

    Kohnle, Antje; Douglass, Margaret; Edwards, Tom J; Gillies, Alastair D; Hooley, Christopher A; Sinclair, Bruce D

    2010-01-01

    In this paper, we describe animations and animated visualizations for introductory and intermediate-level quantum mechanics instruction developed at the University of St Andrews. The animations aim to help students build mental representations of quantum mechanics concepts. They focus on known areas of student difficulty and misconceptions by including animated step-by-step explanations of key points. The animations are freely available, with additional resources available to instructors. We have investigated their educational effectiveness both in terms of student attitude and performance. Questionnaires showed that students are on the whole very positive about the animations and make substantial use of them. A diagnostic survey administered to level 2 and 3 students showed that level 2 students significantly outperformed level 3 students on topics which they had investigated using the animations.

  15. Ethical and Animal Welfare Considerations in Relation to Species Selection for Animal Experimentation.

    Science.gov (United States)

    Webster, John

    2014-12-03

    Ethical principles governing the conduct of experiments with animals are reviewed, especially those relating to the choice of species. Legislation requires that the potential harm to animals arising from any procedure should be assessed in advance and justified in terms of its possible benefit to society. Potential harms may arise both from the procedures and the quality of the animals' lifetime experience. The conventional approach to species selection is to use animals with the "lowest degree of neurophysiological sensitivity". However; this concept should be applied with extreme caution in the light of new knowledge. The capacity to experience pain may be similar in mammals, birds and fish. The capacity to suffer from fear is governed more by sentience than cognitive ability, so it cannot be assumed that rodents or farm animals suffer less than dogs or primates. I suggest that it is unethical to base the choice of species for animal experimentation simply on the basis that it will cause less distress within society. A set of responsibilities is outlined for each category of moral agent. These include regulators, operators directly concerned with the conduct of scientific experiments and toxicology trials, veterinarians and animal care staff; and society at large.

  16. Towards ethically improved animal experimentation in the study of animal reproduction.

    Science.gov (United States)

    Blache, D; Martin, G B; Maloney, S K

    2008-07-01

    The ethics of animal-based research is a continuing area of debate, but ethical research protocols do not prevent scientific progress. In this paper, we argue that our current knowledge of the factors that affect reproductive processes provides researchers with a solid foundation upon which they can conduct more ethical research and simultaneously produce data of higher quality. We support this argument by showing how a deep understanding of the genetics, nutrition and temperament of our experimental animals can improve compliance with two of the '3 Rs', reduction and refinement, simply by offering better control over the variance in our experimental model. The outcome is a better experimental design, on both ethical and scientific grounds.

  17. Tupaia belangeri as an experimental animal model for viral infection.

    Science.gov (United States)

    Tsukiyama-Kohara, Kyoko; Kohara, Michinori

    2014-01-01

    Tupaias, or tree shrews, are small mammals that are similar in appearance to squirrels. The morphological and behavioral characteristics of the group have been extensively characterized, and despite previously being classified as primates, recent studies have placed the group in its own family, the Tupaiidae. Genomic analysis has revealed that the genus Tupaia is closer to humans than it is to rodents. In addition, tupaias are susceptible to hepatitis B virus and hepatitis C virus. The only other experimental animal that has been demonstrated to be sensitive to both of these viruses is the chimpanzee, but restrictions on animal testing have meant that experiments using chimpanzees have become almost impossible. Consequently, the development of the tupaia for use as an animal infection model could become a powerful tool for hepatitis virus research and in preclinical studies on drug development.

  18. Causes and consequences of pathogenic processes in evolution: Implications from experimental epilepsy in animals

    NARCIS (Netherlands)

    Godlevsky, L.S.; Luijtelaar, E.L.J.M. van; Shandra, A.A.; Coenen, A.M.L.

    2002-01-01

    Examples from experimental epilepsy in animals are used to illustrate the view that a crucial role of the transfer of mechanisms from compensatory into pathogenic (e.g. lethal ones in the course of a disease), is played by the power of pathologic stimuli. In the genesis of epilepsy it is suggested

  19. Animal experimentation and scientific knowledge: a thought style?

    Directory of Open Access Journals (Sweden)

    Thales de Astrogildo e Tréz

    2010-12-01

    Full Text Available Animal experimentation, besides a research method extensively applied in the production of scientific knowledge, is also considered essential to science and with undeniable historical relevance in advances in human health. In this survey, a questionnaire was applied to a group of researchers involved with research based on non-animal models (n =18, and to another group involved with research based on animal models (n =18. The data analysis was grounded in Ludwik Fleck (1896 -1961 epistemological assumptions. The results suggested that there are at least two thought styles operating in consonance on the same research problem (advances in human health conditions with significantly different conceptions not only concerning the research practices involved, but also the historical conceptions related to the role of animal experimentation.A experimentação animal, além de método amplamente aplicado na produção do conhecimento científico, é considerada como essencial à ciência e com valor histórico inegável no progresso das condições de saúde humana. Neste levantamento, um questionário foi aplicado a um grupo de pesquisadores com trabalhos baseados em modelos não-animais (n =18 e a outro grupo com trabalhos baseados em modelos animais (n =18. A análise de dados se baseou nos pressupostos epitemológicos de Ludwik Fleck (1896-1961. Os dados sugerem que existem pelo menos dois estilos de pensamento operando em consonância sobre o mesmo problema de pesquisa (avanços nas condições de saúde humana, com concepções significativamente diferentes sobre as práticas de pesquisa envolvidas, assim como as concepções históricas relacionadas ao papel da experimentação animal.

  20. Scientific Knowledge and Technology, Animal Experimentation, and Pharmaceutical Development.

    Science.gov (United States)

    Kinter, Lewis B; DeGeorge, Joseph J

    2016-12-01

    Human discovery of pharmacologically active substances is arguably the oldest of the biomedical sciences with origins >3500 years ago. Since ancient times, four major transformations have dramatically impacted pharmaceutical development, each driven by advances in scientific knowledge, technology, and/or regulation: (1) anesthesia, analgesia, and antisepsis; (2) medicinal chemistry; (3) regulatory toxicology; and (4) targeted drug discovery. Animal experimentation in pharmaceutical development is a modern phenomenon dating from the 20th century and enabling several of the four transformations. While each transformation resulted in more effective and/or safer pharmaceuticals, overall attrition, cycle time, cost, numbers of animals used, and low probability of success for new products remain concerns, and pharmaceutical development remains a very high risk business proposition. In this manuscript we review pharmaceutical development since ancient times, describe its coevolution with animal experimentation, and attempt to predict the characteristics of future transformations. © The Author 2016. Published by Oxford University Press on behalf of the Institute for Laboratory Animal Research. All rights reserved. For permissions, please email: journals.permissions@oup.com.

  1. RASopathies: unraveling mechanisms with animal models

    Directory of Open Access Journals (Sweden)

    Granton A. Jindal

    2015-08-01

    Full Text Available RASopathies are developmental disorders caused by germline mutations in the Ras-MAPK pathway, and are characterized by a broad spectrum of functional and morphological abnormalities. The high incidence of these disorders (∼1/1000 births motivates the development of systematic approaches for their efficient diagnosis and potential treatment. Recent advances in genome sequencing have greatly facilitated the genotyping and discovery of mutations in affected individuals, but establishing the causal relationships between molecules and disease phenotypes is non-trivial and presents both technical and conceptual challenges. Here, we discuss how these challenges could be addressed using genetically modified model organisms that have been instrumental in delineating the Ras-MAPK pathway and its roles during development. Focusing on studies in mice, zebrafish and Drosophila, we provide an up-to-date review of animal models of RASopathies at the molecular and functional level. We also discuss how increasingly sophisticated techniques of genetic engineering can be used to rigorously connect changes in specific components of the Ras-MAPK pathway with observed functional and morphological phenotypes. Establishing these connections is essential for advancing our understanding of RASopathies and for devising rational strategies for their management and treatment.

  2. Ethical and Animal Welfare Considerations in Relation to Species Selection for Animal Experimentation

    Directory of Open Access Journals (Sweden)

    John Webster

    2014-12-01

    Full Text Available Ethical principles governing the conduct of experiments with animals are reviewed, especially those relating to the choice of species. Legislation requires that the potential harm to animals arising from any procedure should be assessed in advance and justified in terms of its possible benefit to society. Potential harms may arise both from the procedures and the quality of the animals’ lifetime experience. The conventional approach to species selection is to use animals with the “lowest degree of neurophysiological sensitivity”. However; this concept should be applied with extreme caution in the light of new knowledge. The capacity to experience pain may be similar in mammals, birds and fish. The capacity to suffer from fear is governed more by sentience than cognitive ability, so it cannot be assumed that rodents or farm animals suffer less than dogs or primates. I suggest that it is unethical to base the choice of species for animal experimentation simply on the basis that it will cause less distress within society. A set of responsibilities is outlined for each category of moral agent. These include regulators, operators directly concerned with the conduct of scientific experiments and toxicology trials, veterinarians and animal care staff; and society at large.

  3. Comparative studies on the ossification in several experimental animals

    International Nuclear Information System (INIS)

    Matsuoka, Osamu; Fukuda, Shun

    1978-01-01

    For estimating the risk of the bone seeking radionuclides in man, it is necessary to extrapolate the data of experimental animals to those of man. Detailed information on the biological stages of development, especially on bone growth of several experimental animals and of man is required for better extrapolation. Multi-species comparison of bone growth and ossification was carried out in several mammalian species such as mouse, rat, dog and monkey. The appearance, ossifying process and fusion of the secondary ossification centers in extremities were selected as indicators of the biological stage of bone. The observation of the secondary ossification centers was made by radiography. The maturity process of the secondary ossification centers in each animal was illustrated. The ossifying process of the secondary ossification center could be divided into the following three categories; (1) the acute ossification observed in mouse, rat, dog and monkey (2) the delayed ossification observed in mouse, rat, dog and monkey, (3) the incomplete ossification without complete fusion which is specific in mouse and rat, appeared and continued up to at least 27 weeks in mouse and up to 134 weeks in rat. The results of the study suggested that a mouse 17 weeks old, a rat 17 - 21 weeks old, a dog (beagle) 14 months old and a monkey about 6 years old may correspond to a man about 20 years old. (author)

  4. Animal behavior models of the mechanisms underlying antipsychotic atypicality.

    NARCIS (Netherlands)

    Geyer, M.A.; Ellenbroek, B.A.

    2003-01-01

    This review describes the animal behavior models that provide insight into the mechanisms underlying the critical differences between the actions of typical vs. atypical antipsychotic drugs. Although many of these models are capable of differentiating between antipsychotic and other psychotropic

  5. PARP-1 inhibition alleviates diabetic cardiac complications in experimental animals.

    Science.gov (United States)

    Zakaria, Esraa M; El-Bassossy, Hany M; El-Maraghy, Nabila N; Ahmed, Ahmed F; Ali, Abdelmoneim A

    2016-11-15

    Cardiovascular complications are the major causes of mortality among diabetic population. Poly(ADP-ribose) polymerase-1 enzyme (PARP-1) is activated by oxidative stress leading to cellular damage. We investigated the implication of PARP-1 in diabetic cardiac complications. Type 2 diabetes was induced in rats by high fructose-high fat diet and low streptozotocin dose. PARP inhibitor 4-aminobenzamide (4-AB) was administered daily for ten weeks after diabetes induction. At the end of study, surface ECG, blood pressure and vascular reactivity were studied. PARP-1 activity, reduced glutathione (GSH) and nitrite contents were assessed in heart muscle. Fasting glucose, fructosamine, insulin, and tumor necrosis factor alpha (TNF-α) levels were measured in serum. Finally, histological examination and collagen deposition detection in rat ventricular and aortic sections were carried out. Hearts isolated from diabetic animals showed increased PARP-1 enzyme activity compared to control animals while significantly reduced by 4-AB administration. PARP-1 inhibition by 4-AB alleviated cardiac ischemia in diabetic animals as indicated by ECG changes. PARP-1 inhibition also reduced cardiac inflammation in diabetic animals as evidenced by histopathological changes. In addition, 4-AB administration improved the elevated blood pressure and the associated exaggerated vascular contractility, endothelial destruction and vascular inflammation seen in diabetic animals. Moreover, PARP-1 inhibition decreased serum levels of TNF-α and cardiac nitrite but increased cardiac GSH contents in diabetic animals. However, PARP-1 inhibition did not significantly affect the developed hyperglycemia. Our findings prove that PARP-1 enzyme plays an important role in diabetic cardiac complications through combining inflammation, oxidative stress, and fibrosis mechanisms. Copyright © 2016. Published by Elsevier B.V.

  6. Relevance of experimental animal studies to the human experience

    International Nuclear Information System (INIS)

    Fry, R.J.M.

    1982-01-01

    Animal experiments are being used to examine a number of physical and biological factors that influence risk estimations though not usually in coordination with epidemiologists. It is clear that the different mechanisms involved in different types of tumors are reflected in the diversity of dose-response relationships. The forms of the dose-response relationships are influenced by both the initial events and their expression. Evidence is accumulating that many initiated cells do not get expressed as overt cancers and host factors may play a major role in the expression of potential tumor cells. There is a need for information about the relationship of the natural incidence and susceptibility to radiation induction for more tumor types. Such experiments will help answer the question of which risk estimate models are appropriate for different tumor types and can be carried out on animals. Perhaps because of the importance of host factors risk estimates as a percentage of the natural incidence appear to be similar for human beings and mice for a small number of tumor types. The elucidation of the mechanisms involved in different tissues while a slow business remains an important role of animal experiments

  7. An Experimental Animal Model for Abdominal Fascia Healing after Surgery

    DEFF Research Database (Denmark)

    Burcharth, J; Pommergaard, H-C; Klein, M

    2013-01-01

    be used to evaluate the actively healing fascia. Such an animal model may promote future research in the prevention of IH. Methods: 86 male Sprague-Dawley rats were used to establish a model involving six experiments (experiments A-F). Mechanical testing of the breaking strength of the healed fascia......Background: Incisional hernia (IH) is a well-known complication after abdominal surgical procedures. The exact etiology of IH is still unknown even though many risk factors have been suggested. The aim of this study was to create an animal model of a weakly healed abdominal fascia that could...... was performed by testing tissue strips from the healed fascia versus the unincised control fascia 7 and 28 days postoperatively. Results: During the six experiments a healing model was created that produced significantly weaker coherent fascia when compared with the control tissue measured in terms...

  8. Hepatoprotective activity of Musa paradisiaca on experimental animal models.

    Science.gov (United States)

    Nirmala, M; Girija, K; Lakshman, K; Divya, T

    2012-01-01

    To investigate the hepatoprotective activity of stem of Musa paradisiaca (M. paradisiaca) in CCl4 and paracetamol induced hepatotoxicity models in rats. Hepatoprotective activity of alcoholic and aqueous extracts of stem of M. paradisiaca was demonstrated by using two experimentally induced hepatotoxicity models. Administration of hepatotoxins (CCl4 and paracetamol) showed significant biochemical and histological deteriorations in the liver of experimental animals. Pretreatment with alcoholic extract (500 mg/kg), more significantly and to a lesser extent the alcoholic extract (250 mg/kg) and aqueous extract (500 mg/kg), reduced the elevated levels of the serum enzymes like serum glutamic-oxaloacetic transaminase (SGOT), serum glutamic pyruvic transaminase (SGPT), alkaline phosphatase (ALP) and bilirubin levels and alcoholic and aqueous extracts reversed the hepatic damage towards the normal, which further evidenced the hepatoprotective activity of stem of M. paradisiaca. The alcoholic extract at doses of 250 and 500 mg/kg, p.o. and aqueous extract at a dose of 500 mg/kg, p.o. of stem of M. paradisiaca have significant effect on the liver of CCl4 and paracetamol induced hepatotoxicity animal models.

  9. Drug induced acute kidney injury: an experimental animal study

    International Nuclear Information System (INIS)

    Khan, M.W.A.; Khan, B.T.; Qazi, R.A.; Ashraf, M.; Waqar, M.

    2017-01-01

    Objective: To assess the extent of drug induced nephrotoxicity in laboratory animals for determining the role and extent of iatrogenic kidney damage in patients exposed to nephrotoxic drugs in various clinical setups. Study Design: Randomized control trail. Place and Duration of study: Pharmacology department and animal house of Army Medical College from Jan 2011 to Aug 2011. Material and Methods: Thirty six mixed breed rabbits were used in this study. Animals were randomly divided into six groups consisting of six rabbits in each. Groups were named A, B, C, D, E and F. Group A was control group. Group B was given 0.9% normal saline. Group C rabbits were given acute nephrotoxic single dose of amphotericin B deoxycholate. Group D received 0.9% normal saline 10ml/kg followed by amphotericin B infusion. Group E was injected acute nephrotoxic regimen of cyclosporine and amphotericin B infusion. Group F received saline loading along with acute nephrotoxic regimen of cyclosporine and amphotericin B infusion. Results: Biochemical and histopathological analysis showed significant kidney injury in rabbits exposed to acute nephrotoxic doses of amphotericin B and cyclosporine. Toxicity was additive when the two drugs were administered simultaneously. Group of rabbits with saline loading had significantly lesser kidney damage. Conclusion: Iatrogenic acute kidney damage is a major cause of morbidity in experimental animals exposed to such nephrotoxic drugs like amphotericin B and cyclosporine, used either alone or in combination. Clinical studies are recommended to assess the extent of iatrogenic renal damage in patients and its economic burden. Efficient and cost effective protective measure may be adopted in clinical setups against such adverse effects. (author)

  10. Management of Ocular Diseases Using Lutein and Zeaxanthin: What Have We Learned from Experimental Animal Studies?

    Directory of Open Access Journals (Sweden)

    Chunyan Xue

    2015-01-01

    Full Text Available Zeaxanthin and lutein are two carotenoid pigments that concentrated in the retina, especially in the macula. The effects of lutein and zeaxanthin on the prevention and treatment of various eye diseases, including age-related macular degeneration, diabetic retinopathy and cataract, ischemic/hypoxia induced retinopathy, light damage of the retina, retinitis pigmentosa, retinal detachment, and uveitis, have been studied in different experimental animal models. In these animal models, lutein and zeaxanthin have been reported to have beneficial effects in protecting ocular tissues and cells (especially the retinal neurons against damage caused by different etiological factors. The mechanisms responsible for these effects of lutein and zeaxanthin include prevention of phototoxic damage by absorption of blue light, reduction of oxidative stress through antioxidant activity and free radical scavenging, and their anti-inflammatory and antiangiogenic properties. The results of these experimental animal studies may provide new preventive and therapeutic procedures for clinical management of various vision-threatening diseases.

  11. [Anaerobic digestion of lignocellulosic biomass with animal digestion mechanisms].

    Science.gov (United States)

    Wu, Hao; Zhang, Pan-Yue; Guo, Jian-Bin; Wu, Yong-Jie

    2013-02-01

    Lignocellulosic material is the most abundant renewable resource in the earth. Herbivores and wood-eating insects are highly effective in the digestion of plant cellulose, while anaerobic digestion process simulating animal alimentary tract still remains inefficient. The digestion mechanisms of herbivores and wood-eating insects and the development of anaerobic digestion processes of lignocellulose were reviewed for better understanding of animal digestion mechanisms and their application in design and operation of the anaerobic digestion reactor. Highly effective digestion of lignocellulosic materials in animal digestive system results from the synergistic effect of various digestive enzymes and a series of physical and biochemical reactions. Microbial fermentation system is strongly supported by powerful pretreatment, such as rumination of ruminants, cellulase catalysis and alkali treatment in digestive tract of wood-eating insects. Oxygen concentration gradient along the digestive tract may stimulate the hydrolytic activity of some microorganisms. In addition, the excellent arrangement of solid retention time, digesta flow and end product discharge enhance the animal digestion of wood cellulose. Although anaerobic digestion processes inoculated with rumen microorganisms based rumen digestion mechanisms were developed to treat lignocellulose, the fermentation was more greatly limited by the environmental conditions in the anaerobic digestion reactors than that in rumen or hindgut. Therefore, the anaerobic digestion processes simulating animal digestion mechanisms can effectively enhance the degradation of wood cellulose and other organic solid wastes.

  12. Practical application of stereological methods in experimental kidney animal models.

    Science.gov (United States)

    Fernández García, María Teresa; Núñez Martínez, Paula; García de la Fuente, Vanessa; Sánchez Pitiot, Marta; Muñiz Salgueiro, María Del Carmen; Perillán Méndez, Carmen; Argüelles Luis, Juan; Astudillo González, Aurora

    The kidneys are vital organs responsible for excretion, fluid and electrolyte balance and hormone production. The nephrons are the kidney's functional and structural units. The number, size and distribution of the nephron components contain relevant information on renal function. Stereology is a branch of morphometry that applies mathematical principles to obtain three-dimensional information from serial, parallel and equidistant two-dimensional microscopic sections. Because of the complexity of stereological studies and the lack of scientific literature on the subject, the aim of this paper is to clearly explain, through animal models, the basic concepts of stereology and how to calculate the main kidney stereological parameters that can be applied in future experimental studies. Copyright © 2016 Sociedad Española de Nefrología. Published by Elsevier España, S.L.U. All rights reserved.

  13. Cats on the Couch: The Experimental Production of Animal Neurosis.

    Science.gov (United States)

    Winter, Alison

    2016-03-01

    Argument In the 1940s-50s, one of the most central questions in psychological research related to the nature of neurosis. In the final years of the Second World War and the following decade, neurosis became one of the most prominent psychiatric disorders, afflicting a high proportion of military casualties and veterans. The condition became central to the concerns of several psychological fields, from psychoanalysis to Pavlovian psychology. This paper reconstructs the efforts of Chicago psychiatrist Jules Masserman to study neurosis in the laboratory during the 1940s and 1950s. Masserman used Pavlovian techniques in a bid to subject this central psychoanalytic subject to disciplined scientific experimentation. More generally, his project was an effort to bolster the legitimacy of psychoanalysis as a human science by articulating a convergence of psychoanalytic categories across multiple species. Masserman sought to orchestrate a convergence of psychological knowledge between fields that were often taken to be irreconcilable. A central focus of this paper is the role of moving images in this project, not only as a means of recording experimental data but also as a rhetorical device. The paper argues that for Masserman film played an important role in enabling scientific observers (and then subsequent viewers) to see agency and emotion in the animals they observed.

  14. IVIM: modeling, experimental validation and application to animal models

    International Nuclear Information System (INIS)

    Fournet, Gabrielle

    2016-01-01

    This PhD thesis is centered on the study of the IVIM ('Intravoxel Incoherent Motion') MRI sequence. This sequence allows for the study of the blood microvasculature such as the capillaries, arterioles and venules. To be sensitive only to moving groups of spins, diffusion gradients are added before and after the 180 degrees pulse of a spin echo (SE) sequence. The signal component corresponding to spins diffusing in the tissue can be separated from the one related to spins travelling in the blood vessels which is called the IVIM signal. These two components are weighted by f IVIM which represents the volume fraction of blood inside the tissue. The IVIM signal is usually modelled by a mono-exponential (ME) function and characterized by a pseudo-diffusion coefficient, D*. We propose instead a bi-exponential IVIM model consisting of a slow pool, characterized by F slow and D* slow corresponding to the capillaries as in the ME model, and a fast pool, characterized by F fast and D* fast, related to larger vessels such as medium-size arterioles and venules. This model was validated experimentally and more information was retrieved by comparing the experimental signals to a dictionary of simulated IVIM signals. The influence of the pulse sequence, the repetition time and the diffusion encoding time was also studied. Finally, the IVIM sequence was applied to the study of an animal model of Alzheimer's disease. (author) [fr

  15. Prediction of skin sensitizers using alternative methods to animal experimentation.

    Science.gov (United States)

    Johansson, Henrik; Lindstedt, Malin

    2014-07-01

    Regulatory frameworks within the European Union demand that chemical substances are investigated for their ability to induce sensitization, an adverse health effect caused by the human immune system in response to chemical exposure. A recent ban on the use of animal tests within the cosmetics industry has led to an urgent need for alternative animal-free test methods that can be used for assessment of chemical sensitizers. To date, no such alternative assay has yet completed formal validation. However, a number of assays are in development and the understanding of the biological mechanisms of chemical sensitization has greatly increased during the last decade. In this MiniReview, we aim to summarize and give our view on the recent progress of method development for alternative assessment of chemical sensitizers. We propose that integrated testing strategies should comprise complementary assays, providing measurements of a wide range of mechanistic events, to perform well-educated risk assessments based on weight of evidence. © 2014 Nordic Association for the Publication of BCPT (former Nordic Pharmacological Society).

  16. Animal experimentation in Japan: regulatory processes and application for microbiological studies.

    Science.gov (United States)

    Takahashi-Omoe, H; Omoe, K

    2007-07-01

    We have conducted animal experimentation as a highly effective technique in biological studies. Also in microbiological studies, we have used experimentation to prevent and treat many infectious diseases in humans and animals. In Japan, the 'Law for the Humane Treatment and Management of Animals', which covers the consideration of the three R principles, refinement, replacement and reduction for an international humane approach to animal experimentation came into effect in June 2006. Looking towards the straightforward operation of the law in animal experimentation, three government ministries established new basic guidelines for experimentation performed in their jurisdictional research and testing facilities. For future microbiological studies involving animals in Japan, we need to perform animal experiments according to the basic guidelines in association with overseas management systems. In this report, we discussed essential actions for the management of animal experimentation in microbiological studies in Japan.

  17. Experimental animal models for COPD: a methodological review

    Directory of Open Access Journals (Sweden)

    Vahideh Ghorani

    2017-05-01

    The present review provides various methods used for induction of animal models of COPD, different animals used (mainly mice, guinea pigs and rats and measured parameters. The information provided in this review is valuable for choosing appropriate animal, method of induction and selecting parameters to be measured in studies concerning COPD.

  18. Legal Limitations Regarding Experimentation in the New Animals Act

    Directory of Open Access Journals (Sweden)

    Vera Lucia da Silva

    2016-10-01

    Full Text Available This article introduces the Animal Act provisions about animal testing. At first, it was proposed a bioethical and biolaw theoretical approach. Following, it was mentioned the Arouca Law, current norm that rules the Article 225 on the Federal Constitution, and authorizes experiments on animals. Then was introduced some elements of the Bills in proceeding at the Senate aimed at changing the Arouca Law. The point is to present an interpretation that focus on a wider view of the Animal Act protective aspect, especially concerning animal testing.

  19. Conservation of Salmonella infection mechanisms in plants and animals.

    Directory of Open Access Journals (Sweden)

    Adam Schikora

    Full Text Available Salmonella virulence in animals depends on effectors injected by Type III Secretion Systems (T3SSs. In this report we demonstrate that Salmonella mutants that are unable to deliver effectors are also compromised in infection of Arabidopsis thaliana plants. Transcriptome analysis revealed that in contrast to wild type bacteria, T3SS mutants of Salmonella are compromised in suppressing highly conserved Arabidopsis genes that play a prominent role during Salmonella infection of animals. We also found that Salmonella originating from infected plants are equally virulent for human cells and mice. These results indicate a high degree of conservation in the defense and infection mechanism of animal and plant hosts during Salmonella infection.

  20. Drugs to foster kidney regeneration in experimental animals and humans.

    Science.gov (United States)

    Gagliardini, Elena; Benigni, Ariela

    2014-01-01

    The incidence of kidney diseases is increasing worldwide and they are emerging as a major public health problem. Once mostly considered inexorable, renal disease progression can now be halted and lesions can even regress with drugs such as angiotensin-converting enzyme inhibitors (ACEi) and angiotensin II type I receptor blockers, indicating the possibility of kidney repair. The discovery of renal progenitor cells lining the Bowman capsule of adult rat and human kidneys has shed light on the mechanism of repair by ACEi. Parietal progenitors are a reservoir of cells that contribute to podocyte turnover in physiological conditions. In the early phases of renal disease these progenitors migrate chaotically and subsequently proliferate, accumulating in Bowman's space. The abnormal behavior of parietal progenitors is sustained by the activation of CXCR4 receptors in response to an increased production of the chemokine SDF-1 by podocytes activated by the inflammatory environment. Ang II, via the AT1 receptor, also contributes to progenitor cell proliferation. The CXCR4/SDF-1 and Ang II/AT1 receptor pathogenic pathways both pave the way for lesion formation and subsequent sclerosis. ACEi normalize the CXCR4 and AT1 receptor expression on progenitors, limiting their proliferation, concomitant with the regression of hyperplastic lesions in animals, and in a patient with crescentic glomerulopathy. Understanding the molecular and cellular determinants of regeneration triggered by renoprotective drugs will reveal novel pathways that might be challenged or targeted by pharmacological therapy. © 2014 S. Karger AG, Basel.

  1. Antistress activity of Argyreia speciosa roots in experimental animals

    Directory of Open Access Journals (Sweden)

    Nikunj B Patel

    2011-01-01

    Full Text Available The antistress effect of a seven-day treatment (100 and 200 mg / kg, p.o. of the hydroalcoholic extract of Argyreia speciosa root (ASE was evaluated by using the swimming endurance test, acetic acid-induced writhing test, pentylenetetrazole-induced convulsion test, anoxic tolerance test, cold-restraint, stress-induced gastric ulcers, aspirin-induced ulcers, and biochemical, and histopathological changes in the cold-restraint stress test. The immunomodulatory activity was also evaluated for the same doses, and treatment of ASE was done using the hemagglutination test. Both the doses of ASE showed antistress activity in all the tested models. The ASE-treated animals showed a decrease in immobility time and an increase in anoxic tolerance time in swimming endurance and the anoxic tolerance tests, respectively. The effect of glacial acetic acid and pentylenetetrazole were also reduced by decreasing the number of writhing responses and increasing the onset of convulsions, respectively. In the cold restrained stress and aspirin-induced gastric ulcer models, ASE showed a significant reduction in the ulcer index. Pretreatment with ASE significantly ameliorated the cold stress-induced variations in biochemical levels such as increased plasma cholesterol, triglyceride, glucose, total protein, and cortisol. ASE was also effective in preventing the pathological changes in the adrenal gland, due to cold restrained stress, in rats. In mice immunized with sheep red blood cells, the treatment groups subjected to restraint stress prevented the humoral immune response to the antigen. The immunostimulating activity of the ASE was indicated by an increase in the antibody titer in mice pre-immunized with sheep red blood cells and subjected to restraint stress. The findings of the present investigations indicate that the ASE has significant antistress activity, which may be due to the immunostimulating property and increased resistance, nonspecifically, against all

  2. Quantifying the mechanisms of domain gain in animal proteins.

    Science.gov (United States)

    Buljan, Marija; Frankish, Adam; Bateman, Alex

    2010-01-01

    Protein domains are protein regions that are shared among different proteins and are frequently functionally and structurally independent from the rest of the protein. Novel domain combinations have a major role in evolutionary innovation. However, the relative contributions of the different molecular mechanisms that underlie domain gains in animals are still unknown. By using animal gene phylogenies we were able to identify a set of high confidence domain gain events and by looking at their coding DNA investigate the causative mechanisms. Here we show that the major mechanism for gains of new domains in metazoan proteins is likely to be gene fusion through joining of exons from adjacent genes, possibly mediated by non-allelic homologous recombination. Retroposition and insertion of exons into ancestral introns through intronic recombination are, in contrast to previous expectations, only minor contributors to domain gains and have accounted for less than 1% and 10% of high confidence domain gain events, respectively. Additionally, exonization of previously non-coding regions appears to be an important mechanism for addition of disordered segments to proteins. We observe that gene duplication has preceded domain gain in at least 80% of the gain events. The interplay of gene duplication and domain gain demonstrates an important mechanism for fast neofunctionalization of genes.

  3. Experimental evidence for inherent Lévy search behaviour in foraging animals.

    Science.gov (United States)

    Kölzsch, Andrea; Alzate, Adriana; Bartumeus, Frederic; de Jager, Monique; Weerman, Ellen J; Hengeveld, Geerten M; Naguib, Marc; Nolet, Bart A; van de Koppel, Johan

    2015-05-22

    Recently, Lévy walks have been put forward as a new paradigm for animal search and many cases have been made for its presence in nature. However, it remains debated whether Lévy walks are an inherent behavioural strategy or emerge from the animal reacting to its habitat. Here, we demonstrate signatures of Lévy behaviour in the search movement of mud snails (Hydrobia ulvae) based on a novel, direct assessment of movement properties in an experimental set-up using different food distributions. Our experimental data uncovered clusters of small movement steps alternating with long moves independent of food encounter and landscape complexity. Moreover, size distributions of these clusters followed truncated power laws. These two findings are characteristic signatures of mechanisms underlying inherent Lévy-like movement. Thus, our study provides clear experimental evidence that such multi-scale movement is an inherent behaviour rather than resulting from the animal interacting with its environment. © 2015 The Author(s) Published by the Royal Society. All rights reserved.

  4. Molecular Mechanisms of Microcystin Toxicity in Animal Cells

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    Alexandre Campos

    2010-01-01

    Full Text Available Microcystins (MC are potent hepatotoxins produced by the cyanobacteria of the genera Planktothrix, Microcystis, Aphanizomenon, Nostoc and Anabaena. These cyclic heptapeptides have strong affinity to serine/threonine protein phosphatases (PPs thereby acting as an inhibitor of this group of enzymes. Through this interaction a cascade of events responsible for the MC cytotoxic and genotoxic effects in animal cells may take place. Moreover MC induces oxidative stress in animal cells and together with the inhibition of PPs, this pathway is considered to be one of the main mechanisms of MC toxicity. In recent years new insights on the key enzymes involved in the signal-transduction and toxicity have been reported demonstrating the complexity of the interaction of these toxins with animal cells. Key proteins involved in MC up-take, biotransformation and excretion have been identified, demonstrating the ability of aquatic animals to metabolize and excrete the toxin. MC have shown to interact with the mitochondria. The consequences are the dysfunction of the organelle, induction of reactive oxygen species (ROS and cell apoptosis. MC activity leads to the differential expression/activity of transcriptional factors and protein kinases involved in the pathways of cellular differentiation, proliferation and tumor promotion activity. This activity may result from the direct inhibition of the protein phosphatases PP1 and PP2A. This review aims to summarize the increasing data regarding the molecular mechanisms of MC toxicity in animal systems, reporting for direct MC interacting proteins and key enzymes in the process of toxicity biotransformation/excretion of these cyclic peptides.

  5. Bioinspiration: applying mechanical design to experimental biology.

    Science.gov (United States)

    Flammang, Brooke E; Porter, Marianne E

    2011-07-01

    The production of bioinspired and biomimetic constructs has fostered much collaboration between biologists and engineers, although the extent of biological accuracy employed in the designs produced has not always been a priority. Even the exact definitions of "bioinspired" and "biomimetic" differ among biologists, engineers, and industrial designers, leading to confusion regarding the level of integration and replication of biological principles and physiology. By any name, biologically-inspired mechanical constructs have become an increasingly important research tool in experimental biology, offering the opportunity to focus research by creating model organisms that can be easily manipulated to fill a desired parameter space of structural and functional repertoires. Innovative researchers with both biological and engineering backgrounds have found ways to use bioinspired models to explore the biomechanics of organisms from all kingdoms to answer a variety of different questions. Bringing together these biologists and engineers will hopefully result in an open discourse of techniques and fruitful collaborations for experimental and industrial endeavors.

  6. Secrets and lies: "selective openness" in the apparatus of animal experimentation.

    Science.gov (United States)

    Holmberg, Tora; Ideland, Malin

    2012-04-01

    Researchers and other (human) actors within the apparatus of animal experimentation find themselves in a tight corner. They rely on public acceptance to promote their legitimacy and to receive funding. At the same time, those working with animal experimentation take risks by going public, fearing that the public will misunderstand their work and animal rights activists may threaten them. The dilemma that emerges between openness and secrecy is fairly prevalent in scientific culture as a whole, but the apparatus of animal experimentation presents specific patterns of technologies of secrets. The aim of the paper is to describe and analyse the meanings of secrets and openness in contemporary animal experimentation. We suggest that these secrets--or "selective openness"--can be viewed as grease in the apparatus of animal experimentation, as a unifying ingredient that permits maintenance of status quo in human/animal relations and preserves existing institutional public/ science relations.

  7. Animal Structures and Functions, Science (Experimental): 5314.13.

    Science.gov (United States)

    Silver, Barbara A.

    This unit of instruction was designed to introduce the student to the relationship between structure and function in the animal kingdom, with emphasis given to: (1) the evolution of physiological systems in the major animal phyla, (2) the complementarity of structure and function, and (3) the concept of homeostasis. The booklet lists the relevant…

  8. Implant healing in experimental animal models of diabetes.

    Science.gov (United States)

    Le, Nga N; Rose, Michael B; Levinson, Howard; Klitzman, Bruce

    2011-05-01

    Diabetes mellitus is becoming increasingly prevalent worldwide. Additionally, there is an increasing number of patients receiving implantable devices such as glucose sensors and orthopedic implants. Thus, it is likely that the number of diabetic patients receiving these devices will also increase. Even though implantable medical devices are considered biocompatible by the Food and Drug Administration, the adverse tissue healing that occurs adjacent to these foreign objects is a leading cause of their failure. This foreign body response leads to fibrosis, encapsulation of the device, and a reduction or cessation of device performance. A second adverse event is microbial infection of implanted devices, which can lead to persistent local and systemic infections and also exacerbates the fibrotic response. Nearly half of all nosocomial infections are associated with the presence of an indwelling medical device. Events associated with both the foreign body response and implant infection can necessitate device removal and may lead to amputation, which is associated with significant morbidity and cost. Diabetes mellitus is generally indicated as a risk factor for the infection of a variety of implants such as prosthetic joints, pacemakers, implantable cardioverter defibrillators, penile implants, and urinary catheters. Implant infection rates in diabetic patients vary depending upon the implant and the microorganism, however, for example, diabetes was found to be a significant variable associated with a nearly 7.2% infection rate for implantable cardioverter defibrillators by the microorganism Candida albicans. While research has elucidated many of the altered mechanisms of diabetic cutaneous wound healing, the internal healing adjacent to indwelling medical devices in a diabetic model has rarely been studied. Understanding this healing process is crucial to facilitating improved device design. The purpose of this article is to summarize the physiologic factors that

  9. Animal experimentation: a legal fight in Brazilian universities

    Directory of Open Access Journals (Sweden)

    Fernanda Luiza Fontoura de Medeiros

    2015-07-01

    Full Text Available Vivisection, or the use of animals in experiments, testing or education is part of a context in which many people still think represent an emergency conflict that requires the choice of human interests rather than the interests of animals. In Brazil, the 1988 Federal Constitution, in Article 225, paragraph 1, item VII, prohibits the practice of cruelty to animals. To regulate the said device, was passed in 2008 the Law 11.794 / 2008, known as Arouca Law, establishing procedures for the scientific use of animals and the Law 9.605 / 2008, which deals with environmental crimes. However, according to Brazilian Constitution, is it possible to sustain the use of animals in teaching and research, especially in universities? The aim of this paper is to analyze the Brazilian legislation regarding the use of animals in testing, teaching and research, and to discuss the observation of this legislation during the lawsuits filled in recent years by animal advocacy organizations against several Brazilian universities. The results point to a disagreement between the practices prevailing in the universities, the legislation and the Brazilian Constitution.

  10. Conscientious Objection to Animal Experimentation in Italian Universities.

    Science.gov (United States)

    Baldelli, Ilaria; Massaro, Alma; Penco, Susanna; Bassi, Anna Maria; Patuzzo, Sara; Ciliberti, Rosagemma

    2017-03-13

    In Italy, Law 413/1993 states that public and private Italian Institutions, including academic faculties, are obliged to fully inform workers and students about their right to conscientious objection to scientific or educational activities involving animals, hereafter written as "animal CO". However, little monitoring on the faculties' compliance with this law has been performed either by the government or other institutional bodies. Based on this premise, the authors have critically reviewed the existing data and compared them with those emerging from their own investigation to discuss limitations and inconsistencies. The results of this investigation revealed that less than half of Italian academic faculties comply with their duty to inform on animal CO. Non-compliance may substantially affect the right of students to make ethical choices in the field of animal ethics and undermines the fundamental right to express their own freedom of thought. The Italian Ministry of Education, Universities and Research, ethics committees and animal welfare bodies should cooperate to make faculties respect this law. Further research is needed to better understand the reasons for the current trend, as well as to promote the enforcement of Law 413/1993 with particular regard to information on animal CO.

  11. Conscientious Objection to Animal Experimentation in Italian Universities

    Directory of Open Access Journals (Sweden)

    Ilaria Baldelli

    2017-03-01

    Full Text Available In Italy, Law 413/1993 states that public and private Italian Institutions, including academic faculties, are obliged to fully inform workers and students about their right to conscientious objection to scientific or educational activities involving animals, hereafter written as “animal CO”. However, little monitoring on the faculties’ compliance with this law has been performed either by the government or other institutional bodies. Based on this premise, the authors have critically reviewed the existing data and compared them with those emerging from their own investigation to discuss limitations and inconsistencies. The results of this investigation revealed that less than half of Italian academic faculties comply with their duty to inform on animal CO. Non-compliance may substantially affect the right of students to make ethical choices in the field of animal ethics and undermines the fundamental right to express their own freedom of thought. The Italian Ministry of Education, Universities and Research, ethics committees and animal welfare bodies should cooperate to make faculties respect this law. Further research is needed to better understand the reasons for the current trend, as well as to promote the enforcement of Law 413/1993 with particular regard to information on animal CO.

  12. Gentamicin nephrotoxicity: Animal experimental correlate with human pharmacovigilance outcome

    Directory of Open Access Journals (Sweden)

    Olufunsho Awodele

    2015-04-01

    Full Text Available Background: National Agency for Food and Drugs Administration and Control (NAFDAC, which is responsible for pharmacovigilance activity in Nigeria, recently withdrew injection gentamicin 280 mg, used in the management of life-threatening and multidrug-resistant infections from circulation, due to reported toxicity. Thus, this study aimed to investigate the toxicity profile of the commonly used strengths (80 mg and 280 mg of gentamicin on kidney using animal models. Methods: Animals were divided into five groups of 16 rats each. For rats of groups 1 and 2, gentamicin (1.14 mg/kg each group was administered intramuscularly twice daily for 7 and 14 days, respectively, after which eight of them were sacrificed by cervical dislocation. Blood was collected via cardiac puncture and the kidneys were carefully removed and weighed immediately. The remaining eight animals were kept for reversibility study for another 7 and 14 days, respectively. For groups 3 and 4, gentamicin (4 mg/kg each group was administered as a single daily dose for 7 and 14 days, respectively, and eight animals from the groups were subjected to reversibility study for 7 and 14 days, respectively. Group 5, the control group animals, were given 10 ml/kg distilled water for 14 days. Histopathology of the kidneys, serum creatinine levels, and antioxidant enzyme activities were investigated. Results: Significant increase (p ≤ 0.001 in the level of creatinine of rats administered 4.0 mg/kg for 14 days was observed compared with all other groups. Significant (p ≤ 0.001 elevations in the lipid peroxidation in all gentamicin-administered animals and acute tubular necrosis in most of the gentamicin-administered animals were observed. Conclusion: Toxicity profile of gentamicin on the kidneys is dependent on both dose and duration of administration. The findings justify the decision made by NAFDAC to ban the use of high-dose inj. gentamicin 280 mg in Nigeria.

  13. Seal Formation Mechanism Beneath Animal Waste Holding Ponds

    Science.gov (United States)

    Cihan, A.; Tyner, J. S.; Wright, W. C.

    2005-12-01

    Infiltration of animal waste from holding ponds can cause contamination of groundwater. Typically, the initial flux from a pond decreases rapidly as a seal of animal waste particulates is deposited at the base of the pond. The purpose of this study was to investigate the mechanism of the seal formation. Twenty-four soil columns (10-cm diameter by 43-cm long) were hand-packed with sand, silty loam or clay soils. A 2.3 m column of dairy or swine waste was applied to the top of the each column. The leakage rate from each column was measured with respect to time to analyze the effect of seal formation on different soil textures and animal waste types. We tested our hypothesis that seal growth and the subsequent decrease of leachate production adheres to a filter cake growth model. Said model predicts that the cumulative leakage rate is proportional to the square root of time and to the square root of the height of the waste.

  14. Mechanized syringe homogenization of human and animal tissues.

    Science.gov (United States)

    Kurien, Biji T; Porter, Andrew C; Patel, Nisha C; Kurono, Sadamu; Matsumoto, Hiroyuki; Scofield, R Hal

    2004-06-01

    Tissue homogenization is a prerequisite to any fractionation schedule. A plethora of hands-on methods are available to homogenize tissues. Here we report a mechanized method for homogenizing animal and human tissues rapidly and easily. The Bio-Mixer 1200 (manufactured by Innovative Products, Inc., Oklahoma City, OK) utilizes the back-and-forth movement of two motor-driven disposable syringes, connected to each other through a three-way stopcock, to homogenize animal or human tissue. Using this method, we were able to homogenize human or mouse tissues (brain, liver, heart, and salivary glands) in 5 min. From sodium dodecyl sulfate-polyacrylamide gel electrophoresis analysis and a matrix-assisted laser desorption/ionization time-of-flight mass spectrometric enzyme assay for prolidase, we have found that the homogenates obtained were as good or even better than that obtained used a manual glass-on-Teflon (DuPont, Wilmington, DE) homogenization protocol (all-glass tube and Teflon pestle). Use of the Bio-Mixer 1200 to homogenize animal or human tissue precludes the need to stay in the cold room as is the case with the other hands-on homogenization methods available, in addition to freeing up time for other experiments.

  15. Prevention of occupational risks in animal experimentation; Prevencion de riesgos laborales en experimentacion animal

    Energy Technology Data Exchange (ETDEWEB)

    Martinez Palacio, J. (ed.)

    2007-07-01

    This work focuses on the main specific risks for those working with laboratory animals in a Research Center such as CIEMAT. First we present the general biological risks, their laws and rules. Next, we development the specific risks associated with the laboratory animals, zoonotic diseases and allergies. then we deal with the risks that can be consequence of working with laboratory animals, ionizing radiations, chemical products, genetically modified organisms, liquid nitrogen management, bio containment and human samples management. As they are subjects of interest, we also include the workers health assesment for those exposed to biological agents, including recommendations about hygiene and disinfections. (Author)

  16. Animals from the Outside In, Science (Experimental): 5314.01.

    Science.gov (United States)

    Kleinman, David Z.

    Presented is an outline of a basic course (low level) in biology for students whose interest and background are very limited. The study and dissection of earthworm, crayfish, perch, and bird are included. A detailed study of the frog is undertaken as a representative of the animal kingdom. Performance objectives are presented, as well as a course…

  17. Side effects of pain and analgesia in animal experimentation.

    Science.gov (United States)

    Jirkof, Paulin

    2017-03-22

    This review highlights selected effects of untreated pain and of widely used analgesics such as opioids, non-steroid anti-inflammatory drugs and antipyretics, to illustrate the relevance of carefully planned, appropriate and controlled analgesia for greater reproducibility in animal experiments involving laboratory rodents.

  18. Study of analgesic activity of ethanol extract of Phlogacanthus thyrsiflorus on experimental animal models

    Directory of Open Access Journals (Sweden)

    Apurba Mukherjee

    2009-06-01

    Full Text Available The aim of the study was to evaluate the central and peripheral analgesic action of Phlogacanthus thyrsiflorus in experimental animal models. The extract was prepared by percolation method and acute oral toxicity testing was performed as per OECD guidelines. Analgesic activity was assessed by tail flick method (for central action and glacial acetic acid-induced writhing test (for peripheral action. Leaves extract (500 mg/kg, p.o. and aspirin (100 mg/kg showed significant peripheral analgesic activity (p<0.05. Leaves extract (500 mg/kg, p.o. and pethidine (50 mg/kg, i.p. also showed significant central analgesic activity (p<0.05. Naloxone (1 mg/kg, s.c. was used to find the mechanism of central analgesic action. Some partial agonistic activity for the opioid receptors seems to be probable mechanism of action.

  19. [RESEARCH PROGRESS OF EXPERIMENTAL ANIMAL MODELS OF AVASCULAR NECROSIS OF FEMORAL HEAD].

    Science.gov (United States)

    Yu, Kaifu; Tan, Hongbo; Xu, Yongqing

    2015-12-01

    To summarize the current researches and progress on experimental animal models of avascular necrosis of the femoral head. Domestic and internation literature concerning experimental animal models of avascular necrosis of the femoral head was reviewed and analyzed. The methods to prepare the experimental animal models of avascular necrosis of the femoral head can be mainly concluded as traumatic methods (including surgical, physical, and chemical insult), and non-traumatic methods (including steroid, lipopolysaccharide, steroid combined with lipopolysaccharide, steroid combined with horse serum, etc). Each method has both merits and demerits, yet no ideal methods have been developed. There are many methods to prepare the experimental animal models of avascular necrosis of the femoral head, but proper model should be selected based on the aim of research. The establishment of ideal experimental animal models needs further research in future.

  20. STUDY OF THE TOXIC EFFECTS OF CYPERMETHRIN IN EXPERIMENTAL ANIMALS

    Directory of Open Access Journals (Sweden)

    Syed Mehmood Hasan

    2016-06-01

    Full Text Available This study focuses on the toxic effects of a commercially available pesticide, cypermethrin (CM, on animals. This pesticide was administered in the form of aerosol spray through a nebulizer. The study was performed in four different groups and a constant dose of the pesticide was administered once, twice, thrice and four times a day to the respective group for a period of 30 days. The animals were then dissected to study the pesticide effects on different organs. The organs were preserved in 10% formalin. The tissues were processed by basic histopathological method and the slides were prepared for observation. The results were recorded on a performa and were quantified by a unique scoring system. It is concluded that the injurious effects to the mentioned organs were dose and frequency dependent.

  1. Dry-distillation of experimental animal wastes containing radioisotopes

    International Nuclear Information System (INIS)

    Miyatake, Hideo; Saito, Kazumi; Kurihara, Norio

    1988-01-01

    Mice were dry-distilled at 800deg C for 10 min, after [ 32 P]orthophosphate or L-[4,5- 3 H]leucine was intraperitoneally administered. Phosphorus-32 was quantitatively recovered in the residual solid, whereas 95% of 3 H was found in the distillate (condensed water). When 14 C (L-[U- 14 C]malic acid or L-[U- 14 C]leucine) was administered to mice and they were dry-distilled, 14 C-radioactivity was distributed into two fractions; residual solid and exhaust gas. In these cases, the recovery percentage of 14 C in residual solid was not very high but increased as the treating temperature decreased. It reached about 40% of the administered 14 C at 400deg C for 120 min. By the dry-distillation of animals, their weight was reduced to about 10% in every animal tested (mice, rats and rabbits). The volume was reduced to about 20% in cases of mice and rats, and about 30% in case of rabbits. It was concluded that the dry-distillation can be useful as a pre-treatment for disposal of animal wastes containing radioisotopes. (author)

  2. Studies on the effects of ionizing radiation on the normal and diseased liver in experimental animals

    International Nuclear Information System (INIS)

    Mahmoud, S.A.

    1981-01-01

    The experiments carried out in the present study primarily concerned with the effects of ionizing radiations on the normal and diseased liver in experimental animals (mice). Different radiation intensities and different exposure schemes were used to irradiate both healthy and schistosoma mansoni infected animals. A group of uninfected and unirradiated animals were used as controls. Follow up studies were performed every 6 weeks for 30 weeks. These included histopathological studies of the liver damage at every observation periods for all animal groups

  3. The perception of animal experimentation ethics among Indian teenage school pupils.

    Science.gov (United States)

    Kim, Justin Namuk; Choi, Eun Hee; Kim, Soo-Ki

    2017-03-01

    To promote awareness of animal experimentation ethics among teenagers, we created an educational pamphlet and an accompanying questionnaire. One hundred Indian teenage school pupils were given the pamphlet and subsequently surveyed with the questionnaire, to evaluate: a) their perception of animal experimentation ethics; and b) their opinion on the effectiveness of the pamphlet, according to gender and school grade/age. There was a significant correlation between grade/age and support for animal experimentation, i.e. senior students were more inclined to show support for animal experimentation. There was also a significant correlation between gender and perception of the need to learn about animal experimentation ethics, with girls more likely to feel the need to learn about ethics than boys. In addition, the four questions relating to the usefulness of the pamphlet, and student satisfaction with its content, received positive responses from the majority of the students. Even though the pamphlet was concise, it was apparent that three quarters of the students were satisfied with its content. Gender and age did not influence this level of satisfaction. Overall, our study shows that there is a significant correlation between a pupil`s school grade/age and their support for animal experimentation, and that there is also a significant correlation between gender and the perceived need to learn about animal experimentation ethics. This pilot scheme involving an educational pamphlet and questionnaire could be beneficial in helping to formulate basic strategies for educating teenage school pupils about animal ethics. 2017 FRAME.

  4. Animal models in biological and biomedical research - experimental and ethical concerns.

    Science.gov (United States)

    Andersen, Monica L; Winter, Lucile M F

    2017-09-04

    Animal models have been used in experimental research to increase human knowledge and contribute to finding solutions to biological and biomedical questions. However, increased concern for the welfare of the animals used, and a growing awareness of the concept of animal rights, has brought a greater focus on the related ethical issues. In this review, we intend to give examples on how animals are used in the health research related to some major health problems in Brazil, as well as to stimulate discussion about the application of ethics in the use of animals in research and education, highlighting the role of National Council for the Control of Animal Experimentation (Conselho Nacional de Controle de Experimentação Animal - CONCEA) in these areas. In 2008, Brazil emerged into a new era of animal research regulation, with the promulgation of Law 11794, previously known as the Arouca Law, resulting in an increased focus, and rapid learning experience, on questions related to all aspects of animal experimentation. The law reinforces the idea that animal experiments must be based on ethical considerations and integrity-based assumptions, and provides a regulatory framework to achieve this. This review describes the health research involving animals and the current Brazilian framework for regulating laboratory animal science, and hopes to help to improve the awareness of the scientific community of these ethical and legal rules.

  5. Protein metabolism in marine animals: the underlying mechanism of growth.

    Science.gov (United States)

    Fraser, Keiron P P; Rogers, Alex D

    2007-01-01

    comprise a significant proportion of overall metabolic costs in marine organisms, accurate estimates of the energetic cost per unit of synthesised protein are important. Measured costs of protein metabolism are reviewed, and the very high variability in reported costs highlighted. Two major determinants of protein synthesis rates are the tissue concentration of RNA, often expressed as the RNA to protein ratio, and the RNA activity (k(RNA)). The effects of temperature, nutrition and developmental stage on RNA concentration and activity are considered. This chapter highlights our complete lack of knowledge of protein metabolism in many groups of marine organisms, and the fact we currently have only limited data for animals held under a narrow range of experimental conditions. The potential assistance that genomic methods may provide in increasing our understanding of protein metabolism is described.

  6. Animal Hairs as Water-stimulated Shape Memory Materials: Mechanism and Structural Networks in Molecular Assemblies

    Science.gov (United States)

    Xiao, Xueliang; Hu, Jinlian

    2016-05-01

    Animal hairs consisting of α-keratin biopolymers existing broadly in nature may be responsive to water for recovery to the innate shape from their fixed deformation, thus possess smart behavior, namely shape memory effect (SME). In this article, three typical animal hair fibers were first time investigated for their water-stimulated SME, and therefrom to identify the corresponding net-points and switches in their molecular and morphological structures. Experimentally, the SME manifested a good stability of high shape fixation ratio and reasonable recovery rate after many cycles of deformation programming under water stimulation. The effects of hydration on hair lateral size, recovery kinetics, dynamic mechanical behaviors and structural components (crystal, disulfide and hydrogen bonds) were then systematically studied. SME mechanisms were explored based on the variations of structural components in molecular assemblies of such smart fibers. A hybrid structural network model with single-switch and twin-net-points was thereafter proposed to interpret the water-stimulated shape memory mechanism of animal hairs. This original work is expected to provide inspiration for exploring other natural materials to reveal their smart functions and natural laws in animals including human as well as making more remarkable synthetic smart materials.

  7. compared performances of the experimental digesters of the animal

    African Journals Online (AJOL)

    2014-06-30

    Jun 30, 2014 ... droppings, in different concentrations of Dry Matter (DM), were followed. ... is conditioned largely by the adopted mode of digestion and the physicochemical conditions of ... study proposes the evaluation on an experimental scale, on the one ..... The entry in production of biogas for digester II (with inoculum) ...

  8. CHANGING METABOLIC FUNCTIONS IN EXPERIMENTAL ANIMALS AFTER INTRODUCTION OF THE XENOBIOTIC, IMMUNOTROPIC DRUG AND PROBIOTIC

    Directory of Open Access Journals (Sweden)

    Zvyagintseva O.V.

    2015-05-01

    Full Text Available The aim of the study was to evaluate in vivo changes in metabolic and barrier function of the resistance factors (activity of enzymes of neutrophils, the efficiency of phagocytosis, some biochemical parameters (concentration of ceruloplasmin and haptoglobin and proliferate activity in vitro cells after introduction of copper sulfate, probiotics and immunostimulant "Fungidol" the experimental animals. Material and methods. The in vivo experiments were performed on 6-month-old male rats of Wistar line. Identified the following groups: group 1 - control animals, which were intraperitoneally injected with saline (n = 5; group 2 - animals that were administered saline per os and 48 hours a solution of copper sulphate intraperitoneally (n = 5; group 3 - animals, which were injected with immunotropic drug "Fungidol" per os and 48 hours a solution of copper sulphate intraperitoneally (n = 5; group 4 animals, which were injected with a solution of probiotics per os and 48 hours a solution of copper sulphate intraperitoneally (n = 5. As a probiotic used capsules firm Yogurt that contains active Lactobacillus acidophilus, Lactobacillus rhamnosus, Streptococcus thermophillus, Lactobacillus bulgaricus. The concentration of haptoglobin and ceruloplasmin were determined spectrophotometrically. Oxygen-dependent metabolism of neutrophils was investigated by microscopy according to their ability to absorb nitroblue tetrazolium (NBT-test and restore it to deformazione in the form of granules blue color under the influence of superoxide anion, which is formed in the NADP-oxidase reaction, initiating the process of stimulation of phagocytosis (NBT-test. To determine the barrier function of phagocytic cells by light microscopy to evaluate the activity of phagocytosis of neutrophilic granulocytes with subsequent determination of phagocytic index, phagocytic number and the index of completeness of phagocytosis. As a microbial agent used is a suspension culture of

  9. The use of experimental animals in spa research

    Directory of Open Access Journals (Sweden)

    Iluta Alexandru

    2011-05-01

    Full Text Available A laboratory rat is a rat of species Rattus norvegicus which is bred and kept for scientific research. Laboratory rats have served as an important animal model for reaserch in psychology medicine , and other fields.Laboratory rats share origins with their cousins in domestication , the fancy rats. In 18th century Europe , wild Brown rats ran rampant and this infestation fueled the industry of rat-catching .Rat-cathcers would not only make money by trapping the rodents , but also by turning around and selling them for food , or more importantly , for rat-baiting . Rat-baiting was a popular sport which involved filling a pit with rats and timing how long it took for a terrier to kill them all.

  10. Effects of different ways of fasting in experimental animals

    Directory of Open Access Journals (Sweden)

    Zari Naderi Ghalenoie

    2015-12-01

    Full Text Available While fasting has been practiced for centuries, its beneficial effects was unknown until recently. This review tries to analyze the current literature of how fasting and intermittent fasting (IF could affect clinical pathological parameters, learning, mood and brain plasticity. The effects of different ways of fasting on metabolism and stress were also explored. Animal experiments have elucidated fasting and IF could exert positive effects on learning, mood and brain, plus metabolic functions such lowering plasma glucose and insulin level and improvement in lipid metabolism (reduced visceral fat tissue and increased plasma adiponectin level, and an increased resistance to stress. Thus, more clinical studies are necessary to test the effectiveness of fasting and IF in preventing different diseases.

  11. Research perspectives for pre-screening alternatives to animal experimentation

    International Nuclear Information System (INIS)

    Walum, Erik; Hedander, Jan; Garberg, Per

    2005-01-01

    The MEIC study revealed a high predictivity of in vitro cytotoxicity data for human acute systemic toxicity. The idea, put forward by several authors, that compounds that show high cytotoxicity should not need further testing for confirmation but could be assumed toxic also in vivo provides a convenient concept for the selection of the most relevant compounds for further studies in large sets of chemicals, as in the REACH program. The automated techniques applied in high throughput screening (HTS) by the pharmaceutical and biotech industries to select hits in extensive compound collections represent an opportunity to significantly increase the capacity of cytotoxicity testing. Furthermore, it has been suggested that a combination of cytotoxicity data and some basic biokinetic information would greatly improve the accuracy in the extrapolation from in vitro to in vivo and thus make it possible to identify additional toxic compounds that might have escaped in the initial screen. Such information, which can be obtained in a medium throughput screening mode (MTS), includes biotransformation, absorption and some aspects of distribution. The measurement of the net flux of a compound over a cellular barrier, as the one formed in culture by human Caco-2 cells, gives useful, but limited, information on both gut absorption and blood-brain barrier penetration. The test procedures discussed here, as well as other supplementary in vitro tests, cannot always easily be described in terms of animal-based test replacements. In those instances, the necessary test validation cannot be carried out using animal reference data, and prediction models may have to be adapted to new ideas. Consequently, concepts of prospective validation to supplement the now well-established retrospective validation have to be developed

  12. Experimental investigation of buried tritium in plant and animal tissues

    International Nuclear Information System (INIS)

    Kim, S. B.; Workman, W. J. G.; Davis, P. A.

    2008-01-01

    Buried exchangeable tritium appears as part of organically bound tritium (OBT) in the traditional experimental determination of OBT. Since buried tritium quickly exchanges with hydrogen atoms in the body following ingestion, assuming that it is part of OBT rather than part of tritiated water (HTO) could result in a significant overestimate of the ingestion dose. This paper documents an experimental investigation into the existence, amount and significance of buried tritium in plant and fish samples. OBT concentrations in the samples were determined in the traditional way and also following denaturing with five chemical solutions that break down large molecules and expose buried tritium to exchange with free hydrogen atoms. A comparison of the OBT concentrations before and after denaturing, together with the concentration of HTO in the supernatant obtained after denaturing, suggests that buried OBT may exist but makes up less than 5% of the OBT concentration in plants and at most 20% of the OBT concentration in fish. The effects of rinse time and rinse water volumes were investigated to optimize the removal of exchangeable OBT from the samples. (authors)

  13. Statistics of Scientific Procedures on Living Animals 2014: A new format, and hopefully a new era of diminishing animal experimentation?

    Science.gov (United States)

    Hudson-Shore, Michelle

    2016-03-01

    The Annual Statistics of Scientific Procedures on Living Animals Great Britain 2014 reports a welcome decline in animal experimentation in the UK. However, caution has to be exercised when interpreting these most recent figures, due to the significant changes made to satisfy the requirements of Directive 2010/63/EU as to what information is reported and how it is reported. Comparisons to the figures and trends reported in previous years is difficult, so this paper focuses on the specifics of the current report, providing information on overall animal use and highlighting specific issues associated with genetically-altered animals, fish and primates. There is a detailed discussion of the extent of the changes, commenting on the benefits and disadvantages of the new format, in areas such as severity of procedures, legislation and techniques of special interest. It also considers the consequences of the changes on the effective monitoring of laboratory animal use, the openness and transparency regarding the impacts of animal use, and the implementation of Three Rs initiatives. In addition, suggestions for further improvements to the new format are made to the Home Office. 2016 FRAME.

  14. The importance of reward-evaluating mechanisms for animal welfare

    NARCIS (Netherlands)

    Harst, Johanneke van der; Spruijt, Berry

    An increasing need exists for tools to assess and improve animal welfare in an objective and scientifically based manner. This review presents an overview of knowledge and factors related to animal welfare, and explains a new concept to approach animal welfare research. This concept is based on

  15. Functional aspects of developmental toxicity of polyhalogenated aromatic hydrocarbons in experimental animals and human infants

    NARCIS (Netherlands)

    Brouwer, A.; Ahlborg, U. G.; van den Berg, M.; Birnbaum, L. S.; Boersma, E. R.; Bosveld, B.; Denison, M. S.; Gray, L. E.; Hagmar, L.; Holene, E.

    1995-01-01

    A scientific evaluation was made of functional aspects of developmental toxicity of polychlorinated biphenyls (PCBs), polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs) in experimental animals and in human infants. Persistent neurobehavioral, reproductive and

  16. Experimental liver fibrosis research: update on animal models, legal issues and translational aspects

    Science.gov (United States)

    2013-01-01

    Liver fibrosis is defined as excessive extracellular matrix deposition and is based on complex interactions between matrix-producing hepatic stellate cells and an abundance of liver-resident and infiltrating cells. Investigation of these processes requires in vitro and in vivo experimental work in animals. However, the use of animals in translational research will be increasingly challenged, at least in countries of the European Union, because of the adoption of new animal welfare rules in 2013. These rules will create an urgent need for optimized standard operating procedures regarding animal experimentation and improved international communication in the liver fibrosis community. This review gives an update on current animal models, techniques and underlying pathomechanisms with the aim of fostering a critical discussion of the limitations and potential of up-to-date animal experimentation. We discuss potential complications in experimental liver fibrosis and provide examples of how the findings of studies in which these models are used can be translated to human disease and therapy. In this review, we want to motivate the international community to design more standardized animal models which might help to address the legally requested replacement, refinement and reduction of animals in fibrosis research. PMID:24274743

  17. Experimental determination of mechanical parameters in sensorless ...

    Indian Academy of Sciences (India)

    V S S PAVAN KUMAR HARI

    pulse width modulation (PWM) selected. The three-phase .... and the simulation and experimental results are presented. ... between 0 and Ts due to the process of PWM. Hence, the .... MATLAB SIMULINK with the machine parameters in.

  18. Review of Research Projects on Qualitative and Quantitative Effects of Radiation on Haematopoietic Tissue in Man and Experimental Animal

    Energy Technology Data Exchange (ETDEWEB)

    Hilberg, A. W. [Division of Radiological Health, Department of Health, Education and Welfare, Rockville, MD (United States)

    1967-07-15

    By way of introduction to a review of Research Projects of the Division of Radiological Health concerned with effects of radiation on the haematopoietic tissue in man and the experimental animal, I should like first to discuss briefly the organization of research. Our research is organized into three major disciplines: (1) Epidemiology, (2) Radiation biology, and (3) Environmental sciences. Briefly, epidemiology is concerned with studies, of populations and effects of radiation in.man; radiation biology is concerned with effects in the experimental animal under controlled situations and also concerned with basic research in cellular and sub-cellular effects; and environmental science is concerned with transport mechanisms in the biosphere and how these mechanisms may operate and be interrupted to reduce radiation hazard to man.

  19. Using Computational and Mechanical Models to Study Animal Locomotion

    OpenAIRE

    Miller, Laura A.; Goldman, Daniel I.; Hedrick, Tyson L.; Tytell, Eric D.; Wang, Z. Jane; Yen, Jeannette; Alben, Silas

    2012-01-01

    Recent advances in computational methods have made realistic large-scale simulations of animal locomotion possible. This has resulted in numerous mathematical and computational studies of animal movement through fluids and over substrates with the purpose of better understanding organisms’ performance and improving the design of vehicles moving through air and water and on land. This work has also motivated the development of improved numerical methods and modeling techniques for animal locom...

  20. Ultraviolet radiation-induced carcinogenesis: mechanisms and experimental models

    International Nuclear Information System (INIS)

    Ramasamy, Karthikeyan; Shanmugam, Mohana; Balupillai, Agilan; Govindhasamy, Kanimozhi; Gunaseelan, Srithar; Muthusamy, Ganesan; Robert, Beualah Mary; Nagarajan, Rajendra Prasad

    2017-01-01

    Ultraviolet radiation (UVR) is a very prominent environmental toxic agent. UVR has been implicated in the initiation and progression of photocarcinogenesis. UVR exposure elicits numerous cellular and molecular events which include the generation of inflammatory mediators, DNA damage, epigenetic modifications, and oxidative damages mediated activation of signaling pathways. UVR-initiated signal transduction pathways are believed to be responsible for tumor promotion effects. UVR-induced carcinogenic mechanism has been well studied using various animal and cellular models. Human skin-derived dermal fibroblasts, epidermal keratinocytes, and melanocytes served as excellent cellular model systems for the understanding of UVR-mediated carcinogenic events. Apart from this, scientists developed reconstituted three-dimensional normal human skin equivalent models for the study of UVR signaling pathways. Moreover, hairless mice such as SKH-1, devoid of Hr gene, served as a valuable model for experimental carcinogenesis. Scientists have also used transgenic mice and dorsal portion shaved Swiss albino mice for UVR carcinogenesis studies. In this review, we have discussed the current progress in the study on ultraviolet B (UVB)-mediated carcinogenesis and outlined appropriate experimental models for both ultraviolet A- and UVB-mediated carcinogenesis. (author)

  1. Phototoxicity: Its Mechanism and Animal Alternative Test Methods

    Science.gov (United States)

    Park, Hyeonji; Lim, Kyung-Min

    2015-01-01

    The skin exposure to solar irradiation and photoreactive xenobiotics may produce abnormal skin reaction, phototoxicity. Phototoxicity is an acute light-induced response, which occurs when photoreacive chemicals are activated by solar lights and transformed into products cytotoxic against the skin cells. Multifarious symptoms of phototoxicity are identified, skin irritation, erythema, pruritis, and edema that are similar to those of the exaggerated sunburn. Diverse organic chemicals, especially drugs, are known to induce phototoxicity, which is probably from the common possession of UV-absorbing benzene or heterocyclic rings in their molecular structures. Both UVB (290~320 nm) and UVA (320~400 nm) are responsible for the manifestation of phototoxicity. Absorption of photons and absorbed energy (hv) by photoactive chemicals results in molecular changes or generates reactive oxygen species and depending on the way how endogenous molecules are affected by phototoxicants, mechanisms of phototoxcity is categorized into two modes of action: Direct when unstable species from excited state directly react with the endogenous molecules, and indirect when endogeneous molecules react with secondary photoproducts. In order to identify phototoxic potential of a chemical, various test methods have been introduced. Focus is given to animal alternative test methods, i.e., in vitro, and in chemico assays as well as in vivo. 3T3 neutral red uptake assay, erythrocyte photohemolysis test, and phototoxicity test using human 3-dimensional (3D) epidermis model are examples of in vitro assays. In chemico methods evaluate the generation of reactive oxygen species or DNA strand break activity employing plasmid for chemicals, or drugs with phototoxic potential. PMID:26191378

  2. Experimental status of quaternionic quantum mechanics

    International Nuclear Information System (INIS)

    Brumby, S.P.; Joshi, G.C.

    1995-01-01

    Analysis of the logical foundations of quantum mechanics indicates the possibility of constructing a theory using quaternionic Hilbert spaces. Whether this mathematical structure reflects reality is a matter for experiment to decide. The only direct search for quaternionic quantum mechanics yet carried out is reviewed and is proposed to look for quaternionic effects in correlated multi-particle systems. It is also discussed how such experiments might distinguish between the several quaternionic models proposed in the literature. 21 refs

  3. Irradiation creep mechanism: an experimental perspective

    International Nuclear Information System (INIS)

    Garner, F.A.; Gelles, D.S.

    1988-01-01

    The object of this effort is to determine the mechanisms involved in radiation-induced deformation of structural materials and to apply these insights for extrapolation of available fast reactor data to fusion-relevant conditions. An extensive review was conducted of a variety of radiation-induced microstructural data, searching for microstructural records of various irradiation creep mechanisms. It was found that the stress-affected evolution of dislocation microstructure during irradiation is considerably more complex than envisioned in most theoretical modeling studies, particularly in the types of interactive feedback mechanisms operating. Reasonably conclusive evidence was found for a SIPA-type mechanism (stress-induced preferential absorption) operating on both Frank loops and network dislocations. Stress-induced preferential loop nucleation (SIPN) processes may also participate but are thought to be overshadowed by the stronger action of the SIPA-type processes operating on Frank interstitial loops. It was not possible to discern from microstructural evidence between second-order SIPA and first-order SIPA mechanisms, the latter arising from anisotropic diffusion. Evidence was presented, however, that validates the operation of stress-induced preferential unfaulting of Frank loops and stress-induced growth of previously stressed material following removal of applied stress. Dislocation glide mechanisms are also participating but the rate appears to be controlled by SIPA-type climb processes. Applied stresses were shown to generate very anisotropic distributions of Burgers vector in the irradiation-induced microstructure. 108 references, 15 figures, 1 table

  4. [Possible evolutionary mechanisms of 'culture' in animals: The hypothesis of distributed social learning].

    Science.gov (United States)

    Reznikova, Zh I; Panteleeva, S N

    2015-01-01

    There is a plethora of works on the origin and genesis of behavioral traditions in different animal species. Nevertheless, it still remains unclear as for which factors facilitate and which factors hinder the spreading those forms of behavior that are new for a population. Here, we present an analytical review on the topic, considering also the results of studies on 'culture' in animals and analyzing contradictions that arise when attempting to clarify the ethological mechanisms of cultural succession. The hypothesis of 'distributed social learning' is formulated, meaning that for spreading of complex behavioral stereotypes in a population the presence of few carriers of consistent stereotypes is enough under the condition that the rest of animals carry incomplete genetic programmes that start up these stereotypes. Existence of 'dormant' fragments of such programmes determines an inborn predisposition of their bearer to perform a certain sequence of acts. To complete the consistent stereotype, the simplest forms of social learning ('social alleviation') turn to be enough. The hypothesis is examined at the behavioral level and supported by experimental data obtained when studying the scenarios of hunting behavior development in ants Myrmica rubra L. It makes possible to explain the spreading of behavioral models in animal communities in a simpler way than cultural succession.

  5. Experimental investigation into the mechanism of folding

    NARCIS (Netherlands)

    Kuenen, Ph.H.; Sitter, de L.U.

    1938-01-01

    The investigation of geological structures due to folding led de Sitter to form an opinion on the mechanical problems involved (Bibl. 7). His principal contention is that in simple cases the relative movements of particles with respect to eachother during deformation leading to a fold, have been

  6. Plasma rico em plaquetas de coelhos: introdução a um modelo animal experimental Platelet-rich plasma in rabbits: introduction of one experimental animal model

    Directory of Open Access Journals (Sweden)

    Marco Antonio de Oliveira-Filho

    2008-12-01

    Full Text Available RACIONAL: Muitas dúvidas ainda permanecem no que se refere às ações dos fatores de crescimento e do plasma rico em plaquetas sobre o mecanismo de reparação tissular. Há necessidade de serem esclarecidos pontos controversos ainda existentes. OBJETIVO: Obter o plasma rico em plaquetas em coelhos através de um método simplificado e ao mesmo tempo adequado, introduzindo um modelo experimental que possa ser utilizado em estudos posteriores. MÉTODOS: Foram utilizados 25 coelhas da raça Nova Zelândia e sem doenças prévias. Quinze mL de sangue de cada animal foi coletado, sendo 10 mL submetidos à dupla centrifugação. Para comprovar a efetividade do método proposto realizou-se contagem mecânica do sangue, bem como do produto final. RESULTADO: Obteve-se uma concentração média de plaquetas no plasma rico em plaquetas 687% maior que a contagem inicial observada no sangue venoso periférico. Para as variáveis: contagem inicial de plaquetas, contagem de plaquetas no plasma rico em plaquetas e enriquecimento, foram obtidos os limites de 95% de confiança para suas médias, sendo que, no que se refere ao percentual de enriquecimento, existe 95% de chance de que o intervalo de (530-844 contenha a média real de enriquecimento de plaquetas. CONCLUSÃO: O método simplificado utilizado permite a obtenção de plasma rico em plaquetas adequado permitindo seu uso em estudos dos fatores de crescimento nos mecanismos de reparação tecidual.BACKGROUND: Multiple uncertainties still exist about the action of the growth factors and the platelet-rich plasma on the mechanism of repair. AIM: To obtain the platelet-rich plasma in rabbits through a simplified and suitable method, creating an experimental model. METHODS: Twenty-five female New Zealand rabbits without previous diseases were used. Fifteen mL of blood of each rabbit was collected and 10 mL of the collected blood were twice centrifugated. To check the effectiveness of the proposed method

  7. PET FACE: MECHANISMS UNDERLYING HUMAN-ANIMAL RELATIONSHIPS

    Directory of Open Access Journals (Sweden)

    Marta eBorgi

    2016-03-01

    Full Text Available Accumulating behavioral and neurophysiological studies support the idea of infantile (cute faces as highly biologically relevant stimuli rapidly and unconsciously capturing attention and eliciting positive/affectionate behaviors, including willingness to care. It has been hypothesized that the presence of infantile physical and behavioral features in companion (or pet animals (i.e. dogs and cats might form the basis of our attraction to these species. Preliminary evidence has indeed shown that the human attentional bias toward the baby schema may extend to animal facial configurations. In this review, the role of facial cues, specifically of infantile traits and facial signals (i.e. eyes gaze as emotional and communicative signals is highlighted and discussed as regulating human-animal bond, similarly to what can be observed in the adult-infant interaction context. Particular emphasis is given to the neuroendocrine regulation of social bond between humans and animals through oxytocin secretion. Instead of considering companion animals as mere baby substitutes for their owners, in this review we highlight the central role of cats and dogs in human lives. Specifically, we consider the ability of companion animals to bond with humans as fulfilling the need for attention and emotional intimacy, thus serving similar psychological and adaptive functions as human-human friendships. In this context, facial cuteness is viewed not just as a releaser of care/parental behavior, but more in general as a trait motivating social engagement. To conclude, the impact of this information for applied disciplines is briefly described, particularly in consideration of the increasing evidence of the beneficial effects of contacts with animals for human health and wellbeing.

  8. Pet Face: Mechanisms Underlying Human-Animal Relationships.

    Science.gov (United States)

    Borgi, Marta; Cirulli, Francesca

    2016-01-01

    Accumulating behavioral and neurophysiological studies support the idea of infantile (cute) faces as highly biologically relevant stimuli rapidly and unconsciously capturing attention and eliciting positive/affectionate behaviors, including willingness to care. It has been hypothesized that the presence of infantile physical and behavioral features in companion (or pet) animals (i.e., dogs and cats) might form the basis of our attraction to these species. Preliminary evidence has indeed shown that the human attentional bias toward the baby schema may extend to animal facial configurations. In this review, the role of facial cues, specifically of infantile traits and facial signals (i.e., eyes gaze) as emotional and communicative signals is highlighted and discussed as regulating the human-animal bond, similarly to what can be observed in the adult-infant interaction context. Particular emphasis is given to the neuroendocrine regulation of the social bond between humans and animals through oxytocin secretion. Instead of considering companion animals as mere baby substitutes for their owners, in this review we highlight the central role of cats and dogs in human lives. Specifically, we consider the ability of companion animals to bond with humans as fulfilling the need for attention and emotional intimacy, thus serving similar psychological and adaptive functions as human-human friendships. In this context, facial cuteness is viewed not just as a releaser of care/parental behavior, but, more in general, as a trait motivating social engagement. To conclude, the impact of this information for applied disciplines is briefly described, particularly in consideration of the increasing evidence of the beneficial effects of contacts with animals for human health and wellbeing.

  9. PATHOGENETIC MECHANISMS IN EXPERIMENTAL IMMUNE FEVER

    Science.gov (United States)

    Root, Richard K.; Wolff, Sheldon M.

    1968-01-01

    When rabbits sensitized to human serum albumin (HSA) are challenged intravenously with specific antigen, fever develops and two transferable pyrogens can be demonstrated in the circulation. The first appears prior to the development of fever and has properties consistent with soluble antigen-antibody complexes. These have been shown to be pyrogenic when prepared in vitro and to produce a state of febrile tolerance when repeatedly administered. The second pyrogen, demonstrable during fever in donor rabbits, appears to be similar to endogenous pyrogen described in other experimental fevers. It is postulated that the formation of antigen-antibody complexes constitutes an important initial phase of the febrile reaction in this type of immune fever. PMID:4873023

  10. Exploratory metabolomics study of the experimental opisthorchiasis in a laboratory animal model (golden hamster, Mesocricetus auratus.

    Directory of Open Access Journals (Sweden)

    Daria A Kokova

    2017-10-01

    Full Text Available Opisthorchiasis is a parasitic infection caused by the liver flukes of the Opisthorchiidae family. Both experimental and epidemiological data strongly support a role of these parasites in the etiology of the hepatobiliary pathologies and an increased risk of intrahepatic cholangiocarcinoma. Understanding a functional link between the infection and hepatobiliary pathologies requires a detailed description a host-parasite interaction on different levels of biological regulation including the metabolic response on the infection. The last one, however, remains practically undocumented. Here we are describing a host response on Opisthorchiidae infection using a metabolomics approach and present the first exploratory metabolomics study of an experimental model of O. felineus infection.We conducted a Nuclear Magnetic Resonance (NMR based longitudinal metabolomics study involving a cohort of 30 animals with two degrees of infection and a control group. An exploratory analysis shows that the most noticeable trend (30% of total variance in the data was related to the gender differences. Therefore further analysis was done of each gender group separately applying a multivariate extension of the ANOVA-ASCA (ANOVA simultaneous component analysis. We show that in the males the infection specific time trends are present in the main component (43.5% variance, while in the females it is presented only in the second component and covers 24% of the variance. We have selected and annotated 24 metabolites associated with the observed effects and provided a physiological interpretation of the findings.The first exploratory metabolomics study an experimental model of O. felineus infection is presented. Our data show that at early stage of infection a response of an organism unfolds in a gender specific manner. Also main physiological mechanisms affected appear rather nonspecific (a status of the metabolic stress the data provides a set of the hypothesis for a search

  11. The relevance of animal experimental results for the assessment of radiation genetic risks in man

    International Nuclear Information System (INIS)

    Stephan, G.

    1981-01-01

    No suitable data are available from man for the quantitative assessment of genetic radiation risk. Therefore, the results from experiments on animals must be utilized. Two hypotheses are presented here in drawing analogical conclusions from one species to another. Although the extrapolation of results from animal experiments remains an open question, the use of experimental results from mice seems to be justified for an assessment of the genetic radiation risk in man. (orig.) [de

  12. The European politics of animal experimentation: From Victorian Britain to 'Stop Vivisection'.

    Science.gov (United States)

    Germain, Pierre-Luc; Chiapperino, Luca; Testa, Giuseppe

    2017-08-01

    This paper identifies a common political struggle behind debates on the validity and permissibility of animal experimentation, through an analysis of two recent European case studies: the Italian implementation of the European Directive 2010/63/EC regulating the use of animals in science, and the recent European Citizens' Initiative (ECI) 'Stop Vivisection'. Drawing from a historical parallel with Victorian antivivisectionism, we highlight important threads in our case studies that mark the often neglected specificities of debates on animal experimentation. From the representation of the sadistic scientist in the XIX century, to his/her claimed capture by vested interests and evasion of public scrutiny in the contemporary cases, we show that animals are not simply the focus of the debate, but also a privileged locus at which much broader issues are being raised about science, its authority, accountability and potential misalignment with public interest. By highlighting this common socio-political conflict underlying public controversies around animal experimentation, our work prompts the exploration of modes of authority and argumentation that, in establishing the usefulness of animals in science, avoid reenacting the traditional divide between epistemic and political fora. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.

  13. 2014 Annual Conference on Experimental and Applied Mechanics

    CERN Document Server

    Korach, Chad; Zavattieri, Pablo; Prorok, Barton; Grande-Allen, K; Carroll, Jay; Daly, Samantha; Qi, H; Antoun, Bonnie; Hall, Richard; Lu, Hongbing; Arzoumanidis, Alex; Silberstein, Meredith; Furmanski, Jevan; Amirkhizi, Alireza; Gonzalez-Gutierrez, Joamin; Jin, Helena; Sciammarella, Cesar; Yoshida, Sanichiro; Lamberti, Luciano; Sottos, Nancy; Rowlands, Robert; Dannemann, Kathryn; Tandon, Gyaneshwar; Song, Bo; Casem, Daniel; Kimberley, Jamie; Starman, LaVern; Hay, Jennifer; Shaw, Gordon

    2015-01-01

    Proceedings of the 2014 Annual Conference on Experimental and Applied Mechanics, the seventh volume of eight from the Conference, brings together contributions to this important area of research and engineering.  The collection presents early findings and case studies on a wide range of areas, including: Soft Tissues Mechanics Natural Materials & Bio-Inspiration Tissue Engineering Cells Mechanics

  14. Alexander von Humboldt: galvanism, animal electricity, and self-experimentation part 2: the electric eel, animal electricity, and later years.

    Science.gov (United States)

    Finger, Stanley; Piccolino, Marco; Stahnisch, Frank W

    2013-01-01

    After extensive experimentation during the 1790s, Alexander von Humboldt remained skeptical about "animal electricity" (and metallic electricity), writing instead about an ill-defined galvanic force. With his worldview and wishing to learn more, he studied electric eels in South America just as the new century began, again using his body as a scientific instrument in many of his experiments. As had been the case in the past and for many of the same reasons, some of his findings with the electric eel (and soon after, Italian torpedoes) seemed to argue against biological electricity. But he no longer used galvanic terminology when describing his electric fish experiments. The fact that he now wrote about animal electricity rather than a different "galvanic" force owed much to Alessandro Volta, who had come forth with his "pile" (battery) for multipling the physical and perceptable effects of otherwise weak electricity in 1800, while Humboldt was deep in South America. Humboldt probably read about and saw voltaic batteries in the United States in 1804, but the time he spent with Volta in 1805 was probably more significant in his conversion from a galvanic to an electrical framework for understanding nerve and muscle physiology. Although he did not continue his animal electricity research program after this time, Humboldt retained his worldview of a unified nature and continued to believe in intrinsic animal electricity. He also served as a patron to some of the most important figures in the new field of electrophysiology (e.g., Hermann Helmholtz and Emil du Bois-Reymond), helping to take the research that he had participated in to the next level.

  15. 2012 Annual Conference on Experimental and Applied Mechanics

    CERN Document Server

    Crone, Wendy; Jin, Helena; Sciammarella, Cesar; Furlong, Cosme; Furlong, Cosme; Chalivendra, Vijay; Song, Bo; Casem, Daniel; Antoun, Bonnie; Qi, H; Hall, Richard; Tandon, GP; Lu, Hongbing; Lu, Charles; Yoshida, Sanichiro; Shaw, Gordon; Prorok, Barton; Barthelat, François; Korach, Chad; Grande-Allen, K; Lipke, Elizabeth; Lykofatitits, George; Zavattieri, Pablo; Starman, LaVern; Patterson, Eann; Backman, David; Cloud, Gary; Vol.1 Dynamic Behavior of Materials; Vol.2 Challenges in Mechanics of Time-Dependent Materials and Processes in Conventional and Multifunctional Materials; Vol.3 Imaging Methods for Novel Materials and Challenging Applications; Vol.4 Experimental and Applied Mechanics; Vol.5 Mechanics of Biological Systems and Materials; Vol.6 MEMS and Nanotechnology; Vol.7 Composite Materials and Joining Technologies for Composites

    2013-01-01

    Experimental and Applied Mechanics, Volume 4: Proceedings of the 2012 Annual Conference on Experimental and Applied Mechanics, the fourth volume of seven from the Conference, brings together 54 contributions to this important area of research and engineering. The collection presents early findings and case studies on fundamental and applied aspects of Experimental and Applied Mechanics, including papers on:  Fracture & Fatigue Microscale & Microstructural Effects in Fatigue & Fracture Material Applications Composite Characterization Using Digital Image Correlation Techniques Multi-Scale Simulation and Testing of Composites Residual Stress Inverse Problems/Hybrid Methods Nano-Composites Microstructure Material Characterization Modeling and Uncertainty Quantification Impact Behavior of Composites.

  16. Animals

    International Nuclear Information System (INIS)

    Skuterud, L.; Strand, P.; Howard, B.J.

    1997-01-01

    The radionuclides of most concern with respect to contamination of animals after a nuclear accident are radioiodine, radiocaesium and radiostrontium (ICRP 30, 1979). Of the other significant anthropogenic radionuclides likely to be released in most accidents, only small proportions of that ingested will be absorbed in an animals gut, and the main animal products, milk and meat, will not normally be contaminated to a significant extent. Animal products will mostly be contaminated as a result of ingestion of contaminated feed and possibly, but to a much lesser extent, from inhalation (for radioiodine only). Direct external contamination of animals is of little or no consequence in human food production. Radioiodine and radiostrontium are important with respect to contamination of milk; radiocaesium contaminates both milk and meat. The physical and chemical form of a radionuclide can influence its absorption in the animal gut. For example, following the Chernobyl accident radiocaesium incorporated into vegetation by root uptake was more readily absorbed than that associated with the original deposit. The transfer of radiocaesium and radiostrontium to animals will be presented both as transfer coefficients and aggregated transfer coefficients. For most animal meat products, only radiocaesium is important as other radionuclides do not significantly contaminate muscle. Farm animal products are the most important foodstuff determining radiocaesium intake by the average consumer in the Nordic countries. The major potential source of radioiodine and radiostrontium to humans is milk and milk products. Of the different species, the smaller animals have the highest transfer of radiocaesium from fodder to meat and milk. (EG)

  17. Generation and application of tri-dimensional animation in mechanical design

    International Nuclear Information System (INIS)

    Liu Li

    2003-01-01

    The mechanical design can be understood vividly and accurately and can be improved in time when there is any mistake if it is made in tri-dimensional animation. The author introduces the generation process and methods for animation in mechanical design with an example

  18. Accumulation and Toxicity of Superparamagnetic Iron Oxide Nanoparticles in Cells and Experimental Animals.

    Science.gov (United States)

    Jarockyte, Greta; Daugelaite, Egle; Stasys, Marius; Statkute, Urte; Poderys, Vilius; Tseng, Ting-Chen; Hsu, Shan-Hui; Karabanovas, Vitalijus; Rotomskis, Ricardas

    2016-08-19

    The uptake and distribution of negatively charged superparamagnetic iron oxide (Fe₃O₄) nanoparticles (SPIONs) in mouse embryonic fibroblasts NIH3T3, and magnetic resonance imaging (MRI) signal influenced by SPIONs injected into experimental animals, were visualized and investigated. Cellular uptake and distribution of the SPIONs in NIH3T3 after staining with Prussian Blue were investigated by a bright-field microscope equipped with digital color camera. SPIONs were localized in vesicles, mostly placed near the nucleus. Toxicity of SPION nanoparticles tested with cell viability assay (XTT) was estimated. The viability of NIH3T3 cells remains approximately 95% within 3-24 h of incubation, and only a slight decrease of viability was observed after 48 h of incubation. MRI studies on Wistar rats using a clinical 1.5 T MRI scanner were showing that SPIONs give a negative contrast in the MRI. The dynamic MRI measurements of the SPION clearance from the injection site shows that SPIONs slowly disappear from injection sites and only a low concentration of nanoparticles was completely eliminated within three weeks. No functionalized SPIONs accumulate in cells by endocytic mechanism, none accumulate in the nucleus, and none are toxic at a desirable concentration. Therefore, they could be used as a dual imaging agent: as contrast agents for MRI and for traditional optical biopsy by using Prussian Blue staining.

  19. Developmental programming of metabolic diseases – a review of studies on experimental animal models

    Directory of Open Access Journals (Sweden)

    Iwona Piotrowska

    2014-06-01

    Full Text Available Growth and development in utero is a complex and dynamic process that requires interaction between the mother organism and the fetus. The delivery of macro – and micronutrients, oxygen and endocrine signals has crucial importance for providing a high level of proliferation, growth and differentiation of cells, and a disruption in food intake not only has an influence on the growth of the fetus, but also has negative consequences for the offspring’s health in the future. Diseases that traditionally are linked to inappropriate life style of adults, such as type 2 diabetes, obesity, and arterial hypertension, can be “programmed” in the early stage of life and the disturbed growth of the fetus leads to the symptoms of the metabolic syndrome. The structural changes of some organs, such as the brain, pancreas and kidney, modifications of the signaling and metabolic pathways in skeletal muscles and in fatty tissue, epigenetic mechanisms and mitochondrial dysfunction are the basis of the metabolic disruptions. The programming of the metabolic disturbances is connected with the disruption in the intrauterine environment experienced in the early and late gestation period. It causes the changes in deposition of triglycerides, activation of the hormonal “stress axis” and disturbances in the offspring’s glucose tolerance. The present review summarizes experimental results that led to the identification of the above-mentioned links and it underlines the role of animal models in the studies of this important concept.

  20. Experimental Autoimmune Encephalomyelitis (EAE) as Animal Models of Multiple Sclerosis (MS).

    Science.gov (United States)

    Glatigny, Simon; Bettelli, Estelle

    2018-01-08

    Multiple sclerosis (MS) is a multifocal demyelinating disease of the central nervous system (CNS) leading to the progressive destruction of the myelin sheath surrounding axons. It can present with variable clinical and pathological manifestations, which might reflect the involvement of distinct pathogenic processes. Although the mechanisms leading to the development of the disease are not fully understood, numerous evidences indicate that MS is an autoimmune disease, the initiation and progression of which are dependent on an autoimmune response against myelin antigens. In addition, genetic susceptibility and environmental triggers likely contribute to the initiation of the disease. At this time, there is no cure for MS, but several disease-modifying therapies (DMTs) are available to control and slow down disease progression. A good number of these DMTs were identified and tested using animal models of MS referred to as experimental autoimmune encephalomyelitis (EAE). In this review, we will recapitulate the characteristics of EAE models and discuss how they help shed light on MS pathogenesis and help test new treatments for MS patients. Copyright © 2018 Cold Spring Harbor Laboratory Press; all rights reserved.

  1. Eating frequency, food intake, and weight: a systematic review of human and animal experimental studies

    Directory of Open Access Journals (Sweden)

    Hollie eRaynor

    2015-12-01

    Full Text Available Eating frequently during the day, or grazing, has been proposed to assist with managing food intake and weight. This systematic review assessed the effect of greater eating frequency (EF on intake and anthropometrics in human and animal experimental studies. Studies were identified through the PubMed electronic database. To be included, studies needed to be conducted in controlled settings or use methods that carefully monitored food intake, and measure food intake or anthropometrics. Studies using human or animal models of disease states (i.e., conditions influencing glucose or lipid metabolism, aside from being overweight or obese, were not included. The 25 reviewed studies (15 human and 10 animal studies contained varying study designs, EF manipulations (1 to 24 eating occasions per day, lengths of experimentation (230 min to 28 weeks, and sample sizes (3 to 56 participants/animals per condition. Studies were organized into four categories for reporting results: 1 human studies conducted in laboratory/metabolic ward settings; 2 human studies conducted in field settings; 3 animal studies with experimental periods 1 month. Out of the 13 studies reporting on consumption, 8 (61.5% found no significant effect of EF. Seventeen studies reported on anthropometrics, with 11 studies (64.7% finding no significant effect of EF. Future, adequately powered, studies should examine if other factors (i.e., disease states, physical activity, energy balance and weight status, long-term increased EF influence the relationship between increased EF and intake and/or anthropometrics.

  2. Experimental mechanics in research work and in practice

    International Nuclear Information System (INIS)

    1989-01-01

    The current state of the art in experimental mechanics is reflected and explained by the 34 conference papers of the 12th GESA symposium. Separate records of 12 papers have been prepared for the ENERGY database. (MM) [de

  3. [Effect of the proteolytic enzyme papain on the body organs and systems of experimental animals].

    Science.gov (United States)

    Udod, V M; Storozhuk, V T; Trofimenko, S P; Shabash, E G; Markelov, S I

    1983-01-01

    When administered intravenously and intraarterially papaine (2.5 and 10 mg/kg) produces no toxic effects on respiration, arterial pressure, brain and intracranial circulation. Intrapleural, intraperitoneal and interstitial administration of papaine solutions in doses under 4.5 mg/kg produces no local or general changes on the part of experimental animals' organism.

  4. Animator

    Science.gov (United States)

    Tech Directions, 2008

    2008-01-01

    Art and animation work is the most significant part of electronic game development, but is also found in television commercials, computer programs, the Internet, comic books, and in just about every visual media imaginable. It is the part of the project that makes an abstract design idea concrete and visible. Animators create the motion of life in…

  5. Expanding the three Rs to meet new challenges in humane animal experimentation.

    Science.gov (United States)

    Schuppli, Catherine A; Fraser, David; McDonald, Michael

    2004-11-01

    The Three Rs are the main principles used by Animal Ethics Committees in the governance of animal experimentation, but they appear not to cover some ethical issues that arise today. These include: a) claims that certain species should be exempted on principle from harmful research; b) increased emphasis on enhancing quality of life of research animals; c) research involving genetically modified (GM) animals; and d) animals bred as models of disease. In some cases, the Three Rs can be extended to cover these developments. The burgeoning use of GM animals in science calls for new forms of reduction through improved genetic modification technology, plus continued attention to alternative approaches and cost-benefit analyses that include the large numbers of animals involved indirectly. The adoption of more expanded definitions of refinement that go beyond minimising distress will capture concerns for enhancing the quality of life of animals through improved husbandry and handling. Targeting refinement to the unpredictable effects of gene modification may be difficult; in these cases, careful attention to monitoring and endpoints are the obvious options. Refinement can also include sharing data about the welfare impacts of gene modifications, and modelling earlier stages of disease, in order to reduce the potential suffering caused to disease models. Other issues may require a move beyond the Three Rs. Certain levels of harm, or numbers and use of certain species, may be unacceptable, regardless of potential benefits. This can be addressed by supplementing the utilitarian basis of the Three Rs with principles based on deontological and relational ethics. The Three Rs remain very useful, but they require thoughtful interpretation and expansion in order for Animal Ethics Committees to address the full range of issues in animal-based research.

  6. Animals

    Energy Technology Data Exchange (ETDEWEB)

    Skuterud, L.; Strand, P. [Norwegian Radiation Protection Authority (Norway); Howard, B.J. [Inst. of Terrestrial Ecology (United Kingdom)

    1997-10-01

    The radionuclides of most concern with respect to contamination of animals after a nuclear accident are radioiodine, radiocaesium and radiostrontium (ICRP 30, 1979). Of the other significant anthropogenic radionuclides likely to be released in most accidents, only small proportions of that ingested will be absorbed in an animals gut, and the main animal products, milk and meat, will not normally be contaminated to a significant extent. Animal products will mostly be contaminated as a result of ingestion of contaminated feed and possibly, but to a much lesser extent, from inhalation (for radioiodine only). Direct external contamination of animals is of little or no consequence in human food production. Radioiodine and radiostrontium are important with respect to contamination of milk; radiocaesium contaminates both milk and meat. The physical and chemical form of a radionuclide can influence its absorption in the animal gut. For example, following the Chernobyl accident radiocaesium incorporated into vegetation by root uptake was more readily absorbed than that associated with the original deposit. The transfer of radiocaesium and radiostrontium to animals will be presented both as transfer coefficients and aggregated transfer coefficients. For most animal meat products, only radiocaesium is important as other radionuclides do not significantly contaminate muscle. Farm animal products are the most important foodstuff determining radiocaesium intake by the average consumer in the Nordic countries. The major potential source of radioiodine and radiostrontium to humans is milk and milk products. Of the different species, the smaller animals have the highest transfer of radiocaesium from fodder to meat and milk. (EG). 68 refs.

  7. Invited review: Experimental design, data reporting, and sharing in support of animal systems modeling research.

    Science.gov (United States)

    McNamara, J P; Hanigan, M D; White, R R

    2016-12-01

    The National Animal Nutrition Program "National Research Support Project 9" supports efforts in livestock nutrition, including the National Research Council's committees on the nutrient requirements of animals. Our objective was to review the status of experimentation and data reporting in animal nutrition literature and to provide suggestions for the advancement of animal nutrition research and the ongoing improvement of field-applied nutrient requirement models. Improved data reporting consistency and completeness represent a substantial opportunity to improve nutrition-related mathematical models. We reviewed a body of nutrition research; recorded common phrases used to describe diets, animals, housing, and environmental conditions; and proposed equivalent numerical data that could be reported. With the increasing availability of online supplementary material sections in journals, we developed a comprehensive checklist of data that should be included in publications. To continue to improve our research effectiveness, studies utilizing multiple research methodologies to address complex systems and measure multiple variables will be necessary. From the current body of animal nutrition literature, we identified a series of opportunities to integrate research focuses (nutrition, reproduction and genetics) to advance the development of nutrient requirement models. From our survey of current experimentation and data reporting in animal nutrition, we identified 4 key opportunities to advance animal nutrition knowledge: (1) coordinated experiments should be designed to employ multiple research methodologies; (2) systems-oriented research approaches should be encouraged and supported; (3) publication guidelines should be updated to encourage and support sharing of more complete data sets; and (4) new experiments should be more rapidly integrated into our knowledge bases, research programs and practical applications. Copyright © 2016 American Dairy Science Association

  8. Persistent influence of maternal obesity on offspring health: Mechanisms from animal models and clinical studies.

    Science.gov (United States)

    Wankhade, Umesh D; Thakali, Keshari M; Shankar, Kartik

    2016-11-05

    The consequences of excessive maternal weight and adiposity at conception for the offspring are now well recognized. Maternal obesity increases the risk of overweight and obesity even in children born with appropriate-for-gestational age (AGA) birth weights. Studies in animal models have employed both caloric excess and manipulation of macronutrients (especially high-fat) to mimic hypercaloric intake present in obesity. Findings from these studies show transmission of susceptibility to obesity, metabolic dysfunction, alterations in glucose homeostasis, hepatic steatosis, skeletal muscle metabolism and neuroendocrine changes in the offspring. This review summarizes the essential literature in this area in both experimental and clinical domains and focuses on the translatable aspects of these experimental studies. Moreover this review highlights emerging mechanisms broadly explaining maternal obesity-associated developmental programming. The roles of early developmental alterations and placental adaptations are also reviewed. Increasing evidence also points to changes in the epigenome and other emerging mechanisms such as alterations in the microbiome that may contribute to persistent changes in the offspring. Finally, we examine potential interventions that have been employed in clinical cohorts. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  9. 2016 Annual Conference on Experimental and Applied Mechanics

    CERN Document Server

    Lamberson, Leslie; Kimberley, Jamie; Korach, Chad; Tekalur, Srinivasan; Zavattieri, Pablo; Yoshida, Sanichiro; Lamberti, Luciano; Sciammarella, Cesar; Ralph, W; Singh, Raman; Tandon, Gyaneshwar; Thakre, Piyush; Zavattieri, Pablo; Zhu, Yong; Zehnder, Alan; Zehnder, Alan; Carroll, Jay; Hazeli, Kavan; Berke, Ryan; Pataky, Garrett; Cavalli, Matthew; Beese, Alison; Xia, Shuman; Starman, La; Hay, Jennifer; Karanjgaokar, Nikhil; Quinn, Simon; Balandraud, Xavier; Cloud, Gary; Patterson, Eann; Backman, David

    2017-01-01

    Dynamic Behavior of Materials, Volume 1 of the Proceedings of the 2016 SEM Annual Conference& Exposition on Experimental and Applied Mechanics, the first volume of ten from the Conference, brings together contributions to this important area of research and engineering. The collection presents early findings and case studies on fundamental and applied aspects of Experimental Mechanics, including papers on: Quantitative Visualization Fracture & Fragmentation Dynamic Behavior of Low Impedance Materials Shock & Blast Dynamic Behavior of Composites Novel Testing Techniques Hybrid Experimental & Computational Methods Dynamic Behavior of Geo-materials General Material Behavior.

  10. Mechanical technology unique to laser fusion experimental systems

    International Nuclear Information System (INIS)

    Hurley, C.A.

    1980-01-01

    Hardware design for laser fusion experimental machines has led to a combination of engineering technologies that are critical to the successful operation of these machines. These large opto-mechanical systems are dependent on extreme cleanliness, accommodation to efficient maintenance, and high stability. These three technologies are the primary mechanical engineering criteria for laser fusion devices

  11. Influence of different methods of internal bone fixation on characteristics of bone callus in experimental animals

    Directory of Open Access Journals (Sweden)

    Gajdobranski Đorđe

    2014-01-01

    Full Text Available Introduction. Correct choice of osteosynthesis method is a very important factor in providing the optimal conditions for appropriate healing of the fracture. There are still disagreements about the method of stabilization of some long bone fractures. Critically observed, no method of fracture fixation is ideal. Each osteosynthesis method has both advantages and weaknesses. Objective. The objective of this study was to compare the results of the experimental application of three different internal fixation methods: plate fixation, intramedullary nail fixation and self-dynamisable internal fixator (SIF. Methods. A series of 30 animals were used (Lepus cuniculus as experimental animals, divided into three groups of ten animals each. Femoral diaphysis of each animal was osteotomized and fixed with one of three implants. Ten weeks later all animals were sacrificed and each specimen underwent histological and biomechanical testing. Results. Histology showed that the healing process with SIF was more complete and bone callus was more mature in comparison to other two methods. During biomechanical investigation (computerized bending stress test, it was documented with high statistical significance that using SIF led to stronger healing ten weeks after the operation. Conclusion. According to the results obtained in this study, it can be concluded that SIF is a suitable method for fracture treatment.

  12. [Christian responsibility and experimental medicine. Experiments with and on humans, experiments on animals].

    Science.gov (United States)

    Grosse, Heinrich W

    2002-01-01

    The Jewish-Christian convictions that man was created as the image of God founded the "ethics of unavailability" which contrast with the utilitarian "ethics of interests." As man s nature is imperfect according to biblical understanding, those responsible in the field of experimental medicine should counteract all tendencies in society which promote an utopian definition of health and an eugenic mentality (idea of the "perfection of mankind"). Consequently, scientists must reflect their own image of man and the effects of their actions on this image. The goals of experimental medicine must also be examined under the aspect of fairness: do they only benefit a minority in the rich industrial nations? As in research on humans, the ethical evaluation of animal experiments must consider the question of the underlying image of humanity and the responsibility of mankind connected to it. Because of changes in society's values, the validity of traditional anthropocentrism is increasingly questioned. However, this does not affect the view of the special position of man as the bearer of responsibility. Even though there are different biblical statements on the relationship between man and animal, the Christian maxim to minimise violence towards animals can be derived from them. In the case of animal experiments this means: experiments which cause the animals severe suffering must be avoided by waiving the potential gain of knowledge from them. In general: in an ethical discussion on medical experiments using humans or animals, the public must be informed completely and involved effectively. A moratorium must be possible before plans become facts. Thinking about ethical problems in the area of experimental medicine should not be separated from the far-reaching questions about changes in our lifestyle and consumer behaviour.

  13. Active Cellular Mechanics and its Consequences for Animal Development

    Science.gov (United States)

    Noll, Nicholas B.

    A central goal of developmental biology is to understand how an organism shapes itself, a process referred to as morphogenesis. While the molecular components critical to determining the initial body plan have been well characterized, the control of the subsequent dynamics of cellular rearrangements which ultimately shape the organism are far less understood. A major roadblock to a more complete picture of morphogenesis is the inability to measure tissue-scale mechanics throughout development and thus answer fundamental questions: How is the mechanical state of the cell regulated by local protein expression and global pattering? In what way does stress feedback onto the larger developmental program? In this dissertation, we begin to approach these questions through the introduction and analysis of a multi-scale model of epithelial mechanics which explicitly connects cytoskeletal protein activity to tissue-level stress. In Chapter 2, we introduce the discrete Active Tension Network (ATN) model of cellular mechanics. ATNs are tissues that satisfy two primary assumptions: that the mechanical balance of cells is dominated by cortical tension and that myosin actively remodels the actin cytoskeleton in a stress-dependent manner. Remarkably, the interplay of these features allows for angle-preserving, i.e. 'isogonal', dilations or contractions of local cell geometry that do not generate stress. Asymptotically this model is stabilized provided there is mechanical feedback on expression of myosin within the cell; we take this to be a strong prediction to be tested. The ATN model exposes a fundamental connection between equilibrium cell geometry and its underlying force network. In Chapter 3, we relax the tension-net approximation and demonstrate that at equilibrium, epithelial tissues with non-uniform pressure have non-trivial geometric constraints that imply the network is described by a weighted `dual' triangulation. We show that the dual triangulation encodes all

  14. Mechanisms and genes in human strial presbycusis from animal models.

    Science.gov (United States)

    Ohlemiller, Kevin K

    2009-06-24

    Schuknecht proposed a discrete form of presbycusis in which hearing loss results principally from degeneration of cochlear stria vascularis and decline of the endocochlear potential (EP). This form was asserted to be genetically linked, and to arise independently from age-related pathology of either the organ of Corti or cochlear neurons. Although extensive strial degeneration in humans coincides with hearing loss, EPs have never been measured in humans, and age-related EP reduction has never been verified. No human genes that promote strial presbycusis have been identified, nor is its pathophysiology well understood. Effective application of animal models to this issue requires models demonstrating EP decline, and preferably, genetically distinct strains that vary in patterns of EP decline and its cellular correlates. Until recently, only two models, Mongolian gerbils and Tyrp1(B-lt) mice, were known to undergo age-associated EP reduction. Detailed studies of seven inbred mouse strains have now revealed three strains (C57BL/6J, B6.CAST-Cdh23(CAST), CBA/J) showing essentially no EP decline with age, and four strains ranging from modest to severe EP reduction (C57BL/6-Tyr(c-2J), BALB/cJ, CBA/CaJ, NOD.NON-H2(nbl)/LtJ). Collectively, animal models support five basic principles regarding a strial form of presbycusis: 1) Progressive EP decline from initially normal levels as a defining characteristic; 2) Non-universality, not all age-associated hearing loss involves EP decline; 3) A clear genetic basis; 4) Modulation by environment or stochastic events; and 5) Independent strial, organ of Corti, and neural pathology. Shared features between human strial presbycusis, gerbils, and BALB/cJ and C57BL/6-Tyr(c-2J) mice further suggest this condition frequently begins with strial marginal cell dysfunction and loss. By contrast, NOD.NON-H2(nbl) mice may model a sequence more closely associated with strial microvascular disease. Additional studies of these and other inbred mouse

  15. Mechanical control of mitotic progression in single animal cells

    OpenAIRE

    Cattin, Cedric J.; Düggelin, Marcel; Martinez-Martin, David; Gerber, Christoph; Müller, Daniel J.; Stewart, Martin P.

    2015-01-01

    Despite the importance of mitotic cell rounding in tissue development and cell proliferation, there remains a paucity of approaches to investigate the mechanical robustness of cell rounding. Here we introduce ion beam-sculpted microcantilevers that enable precise force-feedback-controlled confinement of single cells while characterizing their progression through mitosis. We identify three force regimes according to the cell response: small forces (∼5 nN) that accelerate mitotic progression, i...

  16. Prediction of the health effects of inhaled transuranium elements from experimental animal data

    International Nuclear Information System (INIS)

    Bair, W.J.; Thomas, J.M.

    1976-01-01

    Although animal experiments are conducted to obtain data that can be used to predict the consequences of exposure to alpha-emitting elements on human health, scientists have been hesitant to project the results of animal experiments to man. However, since a human data base does not exist for inhaled transuranics, the animal data cannot be overlooked. The paper describes the derivation of linear non-threshold response relationships for lung cancer in rats after inhalation of alpha-emitting transuranium elements. These relationships were used to calculate risk estimates, which were then compared with a value calculated from the incidence of lung cancer in humans who had been exposed to sources of radiation other than the transuranics. Both estimates were compared with the estimated cancer risk associated with the annual whole-body dose limit of 5 rems for occupational exposure. The rat data suggest that the risk from a working lifetime exposure of 15 rem/a to the lungs from transuranium elements may be 5 times the risk incurred with a whole-body exposure of 5 rem/a, while the human data suggest the risk may be less. Since the histological type of plutonium-induced lung cancer that occurs in experimental animals is rare in man, the use of animal data to estimate risks may be conservative. Risk estimates calculated directly from the results of experiments in which animals actually inhaled transuranic particles circumvent such controversial issues as 'hot particles'. (author)

  17. Comparison of Animal Discs Used in Disc Research to Human Lumbar Disc: Torsion Mechanics and Collagen Content

    Science.gov (United States)

    Showalter, Brent L.; Beckstein, Jesse C.; Martin, John T.; Beattie, Elizabeth E.; Orías, Alejandro A. Espinoza; Schaer, Thomas P.; Vresilovic, Edward J.; Elliott, Dawn M.

    2012-01-01

    Study Design Experimental measurement and normalization of in vitro disc torsion mechanics and collagen content for several animal species used in intervertebral disc research and comparing these to the human disc. Objective To aid in the selection of appropriate animal models for disc research by measuring torsional mechanical properties and collagen content. Summary of Background Data There is lack of data and variability in testing protocols for comparing animal and human disc torsion mechanics and collagen content. Methods Intervertebral disc torsion mechanics were measured and normalized by disc height and polar moment of inertia for 11 disc types in 8 mammalian species: the calf, pig, baboon, goat, sheep, rabbit, rat, and mouse lumbar, and cow, rat, and mouse caudal. Collagen content was measured and normalized by dry weight for the same discs except the rat and mouse. Collagen fiber stretch in torsion was calculated using an analytical model. Results Measured torsion parameters varied by several orders of magnitude across the different species. After geometric normalization, only the sheep and pig discs were statistically different from human. Fiber stretch was found to be highly dependent on the assumed initial fiber angle. The collagen content of the discs was similar, especially in the outer annulus where only the calf and goat discs were statistically different from human. Disc collagen content did not correlate with torsion mechanics. Conclusion Disc torsion mechanics are comparable to human lumbar discs in 9 of 11 disc types after normalization by geometry. The normalized torsion mechanics and collagen content of the multiple animal discs presented is useful for selecting and interpreting results for animal models of the disc. Structural composition of the disc, such as initial fiber angle, may explain the differences that were noted between species after geometric normalization. PMID:22333953

  18. Shexiang Baoxin Pills for Coronary Heart Disease in Animal Models: Preclinical Evidence and Promoting Angiogenesis Mechanism

    Directory of Open Access Journals (Sweden)

    Ke-Jian Zhang

    2017-06-01

    Full Text Available Shexiang Baoxin Pill (SBP originated from a classical TCM Fufang Suhexiang Pill for chest pain with dyspnea in the Southern Song Dynasty (1107–110 AD. Here, we aimed to evaluate preclinical evidence and possible mechanism of SBP for experimental coronary heart disease (CHD. Studies of SBP in animal models with CHD were identified from 6 databases until April 2016. Study quality for each included article was evaluated according to the CAMARADES 10-item checklist. Outcome measures were myocardial infarction area, vascular endothelial growth factor (VEGF and microvessel count (MVC. All the data were analyzed by using RevMan 5.1 software. As a consequence, 25 studies with 439 animals were identified. The quality score of studies ranged from 2 to 5, with the median of 3.6. Meta-analysis of seven studies showed more significant effects of SBP on the reduction of the myocardial infarction area than the control (P < 0.01. Meta-analysis of eight studies showed significant effects of SBP for increasing VEGF expression compared with the control (P < 0.01. Meta-analysis of 10 studies indicated that SBP significantly improved MVC compared with the control (P < 0.01. In conclusion, these findings preliminarily demonstrated that SBP can reduce myocardial infarction area, exerting cardioprotective function largely through promoting angiogenesis.

  19. Music in film and animation: experimental semiotics applied to visual, sound and musical structures

    Science.gov (United States)

    Kendall, Roger A.

    2010-02-01

    The relationship of music to film has only recently received the attention of experimental psychologists and quantificational musicologists. This paper outlines theory, semiotical analysis, and experimental results using relations among variables of temporally organized visuals and music. 1. A comparison and contrast is developed among the ideas in semiotics and experimental research, including historical and recent developments. 2. Musicological Exploration: The resulting multidimensional structures of associative meanings, iconic meanings, and embodied meanings are applied to the analysis and interpretation of a range of film with music. 3. Experimental Verification: A series of experiments testing the perceptual fit of musical and visual patterns layered together in animations determined goodness of fit between all pattern combinations, results of which confirmed aspects of the theory. However, exceptions were found when the complexity of the stratified stimuli resulted in cognitive overload.

  20. Investigation the antinociceptive, antipyretic and antiinflammatory activities of Curcuma aeruginosa Roxb. extracts in experimental animals

    Directory of Open Access Journals (Sweden)

    Arunee Khamjun

    2006-09-01

    Full Text Available Curcuma aeruginosa (C. aeruginosa Roxb. (Zingiberaceae is known in Thai as Waan-Ma-Haa-Mek. The rhizomes of this plant have been used as a component of Thai herbal medicinal recipes used for decreasing dysmenorrhea. In the present study, the analgesic, antipyretic and anti-inflammatory actions of this plant were investigated in experimental animals. The rhizomes of C. aeruginosa were extracted with chloroform, methanol and water to give chloroform, methanol and aqueous extracts, respectively. The effects of the three extracts on nociceptive response using writhing, hot plate and formalin tests in mice were performed. The antipyretic activity in yeast-induced fever and the anti-inflammatory activity in carrageenin-induced edema in rats, were examined. The LD50 value of orally administered the chloroform extract and methanol extract in mice was 3.03 g/kg. No dead mice were observed after oral administration of aqueous extract at the dose of 10 g/kg. Oral administration of the chloroform extract and the methanol extract of C. aeruginosa rhizomes (100-400 mg/kg significantly decreased the number of writhings and stretchings induced by acetic acid. Only the chloroform extract suppressed the licking activity of the late phase in the formalin test in mice. All extracts of C. aeruginosa rhizomes had no effects on heat-induced pain in mice, yeast-induced fever and carrageenin-induced edema in rats. These results suggest that the chloroform extract of C. aeruginosa rhizome possesses analgesic effect via a different mechanism from that of the aspirin.

  1. Annual tendency of research papers used ICR mice as experimental animals in biomedical research fields

    OpenAIRE

    Kim, Ji Eun; Nam, Jung Hoon; Cho, Joon Young; Kim, Kil Soo; Hwang, Dae Youn

    2017-01-01

    Institute of Cancer Research (ICR) mice have been widely used in various research fields including toxicology, oncology, pharmacology, and pharmaceutical product safety testing for decades. However, annual tendency of research papers involving ICR mice in various biomedical fields has not been previously analyzed. In this study, we examined the numbers of papers that used ICR mice as experimental animals in the social science, natural science, engineering, medicine-pharmacy, marine agricultur...

  2. Animal experimentation in Spacelab - Present and future U.S. plans

    Science.gov (United States)

    Berry, W. E.; Dant, C. C.

    1983-01-01

    Current development of life-sciences hardware and experiments for the fourth Spacelab mission in the Life Sciences Flight Experiments Program at NASA Ames is reviewed. The research-animal holding facility, the general-purpose work station, and the life sciences laboratory equipment are characterized, and the 14 Ames projects accepted for the mission are listed and discussed. Several hardware systems and experimental procedures will be verified on the Spacelab-3 mission scheduled for late 1984.

  3. Study Design Rigor in Animal-Experimental Research Published in Anesthesia Journals.

    Science.gov (United States)

    Hoerauf, Janine M; Moss, Angela F; Fernandez-Bustamante, Ana; Bartels, Karsten

    2018-01-01

    Lack of reproducibility of preclinical studies has been identified as an impediment for translation of basic mechanistic research into effective clinical therapies. Indeed, the National Institutes of Health has revised its grant application process to require more rigorous study design, including sample size calculations, blinding procedures, and randomization steps. We hypothesized that the reporting of such metrics of study design rigor has increased over time for animal-experimental research published in anesthesia journals. PubMed was searched for animal-experimental studies published in 2005, 2010, and 2015 in primarily English-language anesthesia journals. A total of 1466 publications were graded on the performance of sample size estimation, randomization, and blinding. Cochran-Armitage test was used to assess linear trends over time for the primary outcome of whether or not a metric was reported. Interrater agreement for each of the 3 metrics (power, randomization, and blinding) was assessed using the weighted κ coefficient in a 10% random sample of articles rerated by a second investigator blinded to the ratings of the first investigator. A total of 1466 manuscripts were analyzed. Reporting for all 3 metrics of experimental design rigor increased over time (2005 to 2010 to 2015): for power analysis, from 5% (27/516), to 12% (59/485), to 17% (77/465); for randomization, from 41% (213/516), to 50% (243/485), to 54% (253/465); and for blinding, from 26% (135/516), to 38% (186/485), to 47% (217/465). The weighted κ coefficients and 98.3% confidence interval indicate almost perfect agreement between the 2 raters beyond that which occurs by chance alone (power, 0.93 [0.85, 1.0], randomization, 0.91 [0.85, 0.98], and blinding, 0.90 [0.84, 0.96]). Our hypothesis that reported metrics of rigor in animal-experimental studies in anesthesia journals have increased during the past decade was confirmed. More consistent reporting, or explicit justification for absence

  4. Experimental studies in the bronchial circulation. Which is the ideal animal model?

    Science.gov (United States)

    Panagiotou, Ioannis; Tsipas, Panteleimon; Melachrinou, Maria; Alexopoulos, Dimitrios; Dougenis, Dimitrios

    2014-01-01

    Background The importance of the role of bronchial arteries is notable in modern days thoracic surgery. The significance of their anastomoses with adjusted structures has not yet been sufficiently rated, especially in cases of haemoptysis, heart-lung transplantations and treatment of aneurysms of the thoracic aorta. The need of a thorough study is more relevant than ever and appropriate laboratory animals are required. Methods We review the literature in order to highlight the ideal experimental animal for the implementation of pilot programs relative to the bronchial circulation. A comparative analysis of the anatomy of the bronchial arterial system in humans along with these of pigs, dogs, rats, and birds, as being the most commonly used laboratory animals, is presented in details. Results The pig has the advantage that the broncho-oesophageal artery usually originates from the aorta as a single vessel, which makes the recognition and dissection of the artery easy to perform. In dogs, there is significant anatomical variation of the origin of the bronchial arteries. In rats, bronchial artery coming from the aorta is a rare event while in birds the pattern of the bronchial artery tree is clearly different from the human analog. Conclusions The pig is anatomically and physiologically suited for experimental studies on the bronchial circulation. The suitable bronchial anatomy and physiology along with the undeniable usefulness of the pig in experimental research and the low maintenance cost make the pig the ideal model for experiments in bronchial circulation. PMID:25364530

  5. A Knockout Experiment: Disciplinary Divides and Experimental Skill in Animal Behaviour Genetics.

    Science.gov (United States)

    Nelson, Nicole C

    2015-07-01

    In the early 1990s, a set of new techniques for manipulating mouse DNA allowed researchers to 'knock out' specific genes and observe the effects of removing them on a live mouse. In animal behaviour genetics, questions about how to deploy these techniques to study the molecular basis of behaviour became quite controversial, with a number of key methodological issues dissecting the interdisciplinary research field along disciplinary lines. This paper examines debates that took place during the 1990s between a predominately North American group of molecular biologists and animal behaviourists around how to design, conduct, and interpret behavioural knockout experiments. Drawing from and extending Harry Collins's work on how research communities negotiate what counts as a 'well-done experiment,' I argue that the positions practitioners took on questions of experimental skill reflected not only the experimental traditions they were trained in but also their differing ontological and epistemological commitments. Different assumptions about the nature of gene action, eg., were tied to different positions in the knockout mouse debates on how to implement experimental controls. I conclude by showing that examining representations of skill in the context of a community's knowledge commitments sheds light on some of the contradictory ways in which contemporary animal behaviour geneticists talk about their own laboratory work as a highly skilled endeavour that also could be mechanised, as easy to perform and yet difficult to perform well.

  6. The effectiveness of health animations in audiences with different health literacy levels: an experimental study.

    Science.gov (United States)

    Meppelink, Corine S; van Weert, Julia C M; Haven, Carola J; Smit, Edith G

    2015-01-13

    Processing Web-based health information can be difficult, especially for people with low health literacy. Presenting health information in an audiovisual format, such as animation, is expected to improve understanding among low health literate audiences. The aim of this paper is to investigate what features of spoken health animations improve information recall and attitudes and whether there are differences between health literacy groups. We conducted an online experiment among 231 participants aged 55 years or older with either low or high health literacy. A 2 (spoken vs written text) x 2 (illustration vs animation) design was used. Participants were randomly exposed to one of the four experimental messages, all providing the same information on colorectal cancer screening. The results showed that, among people with low health literacy, spoken messages about colorectal cancer screening improved recall (P=.03) and attitudes (P=.02) compared to written messages. Animations alone did not improve recall, but when combined with spoken text, they significantly improved recall in this group (P=.02). When exposed to spoken animations, people with low health literacy recalled the same amount of information as their high health literate counterparts (P=.12), whereas in all other conditions people with high health literacy recalled more information compared to low health literate individuals. For people with low health literacy, positive attitudes mediated the relationship between spoken text and the intention to have a colorectal cancer screening (b=.12; 95% CI 0.02-0.25). We conclude that spoken animation is the best way to communicate complex health information to people with low health literacy. This format can even bridge the information processing gap between audiences with low and high health literacy as the recall differences between the two groups are eliminated. As animations do not negatively influence high health literate audiences, it is concluded that

  7. The Effectiveness of Health Animations in Audiences With Different Health Literacy Levels: An Experimental Study

    Science.gov (United States)

    van Weert, Julia CM; Haven, Carola J; Smit, Edith G

    2015-01-01

    Background Processing Web-based health information can be difficult, especially for people with low health literacy. Presenting health information in an audiovisual format, such as animation, is expected to improve understanding among low health literate audiences. Objective The aim of this paper is to investigate what features of spoken health animations improve information recall and attitudes and whether there are differences between health literacy groups. Methods We conducted an online experiment among 231 participants aged 55 years or older with either low or high health literacy. A 2 (spoken vs written text) x 2 (illustration vs animation) design was used. Participants were randomly exposed to one of the four experimental messages, all providing the same information on colorectal cancer screening. Results The results showed that, among people with low health literacy, spoken messages about colorectal cancer screening improved recall (P=.03) and attitudes (P=.02) compared to written messages. Animations alone did not improve recall, but when combined with spoken text, they significantly improved recall in this group (P=.02). When exposed to spoken animations, people with low health literacy recalled the same amount of information as their high health literate counterparts (P=.12), whereas in all other conditions people with high health literacy recalled more information compared to low health literate individuals. For people with low health literacy, positive attitudes mediated the relationship between spoken text and the intention to have a colorectal cancer screening (b=.12; 95% CI 0.02-0.25). Conclusions We conclude that spoken animation is the best way to communicate complex health information to people with low health literacy. This format can even bridge the information processing gap between audiences with low and high health literacy as the recall differences between the two groups are eliminated. As animations do not negatively influence high health

  8. New experimental model for single liver lobe hyperthermia in small animals using non-directional microwaves.

    Directory of Open Access Journals (Sweden)

    Ionuț Tudorancea

    Full Text Available Our aim was to develop a new experimental model for in vivo hyperthermia using non-directional microwaves, applicable to small experimental animals. We present an affordable approach for targeted microwave heat delivery to an isolated liver lobe in rat, which allows rapid, precise and stable tissue temperature control.A new experimental model is proposed. We used a commercial available magnetron generating 2450 MHz, with 4.4V and 14A in the filament and 4500V anodic voltage. Modifications were required in order to adjust tissue heating such as to prevent overheating and to allow for fine adjustments according to real-time target temperature. The heating is controlled using a virtual instrument application implemented in LabView® and responds to 0.1° C variations in the target. Ten healthy adult male Wistar rats, weighing 250-270 g were used in this study. The middle liver lobe was the target for controlled heating, while the rest of the living animal was protected.In vivo microwave delivery using our experimental setting is safe for the animals. Target tissue temperature rises from 30°C to 40°C with 3.375°C / second (R2 = 0.9551, while the increment is lower it the next two intervals (40-42°C and 42-44°C with 0.291°C/ s (R2 = 0.9337 and 0.136°C/ s (R2 = 0.7894 respectively, when testing in sequences. After reaching the desired temperature, controlled microwave delivery insures a very stable temperature during the experiments.We have developed an inexpensive and easy to manufacture system for targeted hyperthermia using non-directional microwave radiation. This system allows for fine and stable temperature adjustments within the target tissue and is ideal for experimental models testing below or above threshold hyperthermia.

  9. Impact of Animal Waste Application on Runoff Water Quality in Field Experimental Plots

    Directory of Open Access Journals (Sweden)

    Paul B. Tchounwou

    2005-08-01

    Full Text Available Animal waste from dairy and poultry operations is an economical and commonly used fertilizer in the state of Louisiana. The application of animal waste to pasture lands not only is a source of fertilizer, but also allows for a convenient method of waste disposal. The disposal of animal wastes on land is a potential nonpoint source of water degradation. Water degradation and human health is a major concern when considering the disposal of large quantities of animal waste. The objective of this research was to determine the effect of animal waste application on biological (fecal coliform, Enterobacter spp. and Escherichia coli and physical/chemical (temperature, pH, nitrate nitrogen, ammonia nitrogen, phosphate, copper, zinc, and sulfate characteristics of runoff water in experimental plots. The effects of the application of animal waste have been evaluated by utilizing experimental plots and simulated rainfall events. Samples of runoff water were collected and analyzed for fecal coliforms. Fecal coliforms isolated from these samples were identified to the species level. Chemical analysis was performed following standard test protocols. An analysis of temperature, ammonia nitrogen, nitrate nitrogen, iron, copper, phosphate, potassium, sulfate, zinc and bacterial levels was performed following standard test protocols as presented in Standard Methods for the Examination of Water and Wastewater [1]. In the experimental plots, less time was required in the tilled broiler litter plots for the measured chemicals to decrease below the initial pre-treatment levels. A decrease of over 50% was noted between the first and second rainfall events for sulfate levels. This decrease was seen after only four simulated rainfall events in tilled broiler litter plots whereas broiler litter plots required eight simulated rainfall events to show this same type of reduction. A reverse trend was seen in the broiler litter plots and the tilled broiler plots for potassium

  10. Impact of animal waste application on runoff water quality in field experimental plots.

    Science.gov (United States)

    Hill, Dagne D; Owens, William E; Tchoounwou, Paul B

    2005-08-01

    Animal waste from dairy and poultry operations is an economical and commonly used fertilizer in the state of Louisiana. The application of animal waste to pasture lands not only is a source of fertilizer, but also allows for a convenient method of waste disposal. The disposal of animal wastes on land is a potential nonpoint source of water degradation. Water degradation and human health is a major concern when considering the disposal of large quantities of animal waste. The objective of this research was to determine the effect of animal waste application on biological (fecal coliform, Enterobacter spp. and Escherichia coli) and physical/chemical (temperature, pH, nitrate nitrogen, ammonia nitrogen, phosphate, copper, zinc, and sulfate) characteristics of runoff water in experimental plots. The effects of the application of animal waste have been evaluated by utilizing experimental plots and simulated rainfall events. Samples of runoff water were collected and analyzed for fecal coliforms. Fecal coliforms isolated from these samples were identified to the species level. Chemical analysis was performed following standard test protocols. An analysis of temperature, ammonia nitrogen, nitrate nitrogen, iron, copper, phosphate, potassium, sulfate, zinc and bacterial levels was performed following standard test protocols as presented in Standard Methods for the Examination of Water and Wastewater [1]. In the experimental plots, less time was required in the tilled broiler litter plots for the measured chemicals to decrease below the initial pre-treatment levels. A decrease of over 50% was noted between the first and second rainfall events for sulfate levels. This decrease was seen after only four simulated rainfall events in tilled broiler litter plots whereas broiler litter plots required eight simulated rainfall events to show this same type of reduction. A reverse trend was seen in the broiler litter plots and the tilled broiler plots for potassium. Bacteria numbers

  11. Animal Assisted Interactions to Alleviate Psychological Symptoms in Patients on Mechanical Ventilation.

    Science.gov (United States)

    Hetland, Breanna; Bailey, Tanya; Prince-Paul, Maryjo

    2017-12-01

    Mechanical ventilation is a common life support intervention for critically ill patients that can cause stressful psychological symptoms. Animal assisted interactions have been used in variety of inpatient settings to reduce symptom burden and promote overall well-being. Due to the severity of illness associated with critical care, use of highly technological equipment, and heightened concern for infection control and patient safety, animal-assisted interaction has not been widely adopted in the intensive care unit. This case study of the therapeutic interaction between a canine and a mechanically ventilated patient provides support for the promotion of animal-assisted interactions as an innovative symptom management strategy in the intensive care unit.

  12. Optimizing laboratory animal stress paradigms: The H-H* experimental design.

    Science.gov (United States)

    McCarty, Richard

    2017-01-01

    Major advances in behavioral neuroscience have been facilitated by the development of consistent and highly reproducible experimental paradigms that have been widely adopted. In contrast, many different experimental approaches have been employed to expose laboratory mice and rats to acute versus chronic intermittent stress. An argument is advanced in this review that more consistent approaches to the design of chronic intermittent stress experiments would provide greater reproducibility of results across laboratories and greater reliability relating to various neural, endocrine, immune, genetic, and behavioral adaptations. As an example, the H-H* experimental design incorporates control, homotypic (H), and heterotypic (H*) groups and allows for comparisons across groups, where each animal is exposed to the same stressor, but that stressor has vastly different biological and behavioral effects depending upon each animal's prior stress history. Implementation of the H-H* experimental paradigm makes possible a delineation of transcriptional changes and neural, endocrine, and immune pathways that are activated in precisely defined stressor contexts. Copyright © 2016 Elsevier Ltd. All rights reserved.

  13. Biological cell as a soft magnetoelectric material: Elucidating the physical mechanisms underpinning the detection of magnetic fields by animals

    Science.gov (United States)

    Krichen, S.; Liu, L.; Sharma, P.

    2017-10-01

    Sharks, birds, bats, turtles, and many other animals can detect magnetic fields. Aside from using this remarkable ability to exploit the terrestrial magnetic field map to sense direction, a subset is also able to implement a version of the so-called geophysical positioning system. How do these animals detect magnetic fields? The answer to this rather deceptively simple question has proven to be quite elusive. The currently prevalent theories, while providing interesting insights, fall short of explaining several aspects of magnetoreception. For example, minute magnetic particles have been detected in magnetically sensitive animals. However, how is the detected magnetic field converted into electrical signals given any lack of experimental evidence for relevant electroreceptors? In principle, a magnetoelectric material is capable of converting magnetic signals into electricity (and vice versa). This property, however, is rare and restricted to a rather small set of exotic hard crystalline materials. Indeed, such elements have never been detected in the animals studied so far. In this work we quantitatively outline the conditions under which a biological cell may detect a magnetic field and convert it into electrical signals detectable by biological cells. Specifically, we prove the existence of an overlooked strain-mediated mechanism and show that most biological cells can act as nontrivial magnetoelectric materials provided that the magnetic permeability constant is only slightly more than that of a vacuum. The enhanced magnetic permeability is easily achieved by small amounts of magnetic particles that have been experimentally detected in magnetosensitive animals. Our proposed mechanism appears to explain most of the experimental observations related to the physical basis of magnetoreception.

  14. The Magnus-Rademaker Scientific Film Collection: Ethical Issues on Animal Experimentation (1908-1940).

    Science.gov (United States)

    Koehler, Peter J; Lameris, Bregt

    2016-01-01

    The Magnus-Rademaker scientific film collection (1908-1940) deals with the physiology of body posture by the equilibrium of reflex musculature contractions for which experimental studies were carried out with animals (e.g., labyrinthectomies, cerebellectomies, and brain stem sections) as well as observations done on patients. The films were made for demonstrations at congresses as well as educational objectives and film stills were published in their books. The purpose of the present study is to position these films and their makers within the contemporary discourse on ethical issues and animal rights in the Netherlands and the earlier international debates. Following an introduction on animal rights and antivivisection movements, we describe what Magnus and Rademaker thought about these issues. Their publications did not provide much information in this respect, probably reflecting their adherence to implicit ethical codes that did not need explicit mentioning in publications. Newspaper articles, however, revealed interesting information. Unnecessary suffering of an animal never found mercy in Magnus' opinion. The use of cinematography was expanded to the reduction of animal experimentation in student education, at least in the case of Rademaker, who in the 1930s was involved in a governmental committee for the regulation of vivisection and cooperated with the antivivisection movement. This resulted not only in a propaganda film for the movement but also in films that demonstrate physiological experiments for students with the purpose to avert repetition and to improve the teaching of experiments. We were able to identify the pertinent films in the Magnus-Rademaker film collection. The production of vivisection films with this purpose appears to have been common, as is shown in news messages in European medical journals of the period.

  15. [Change of blood antioxidant capacity of experimental animals during nutritional correction under oxidative stress].

    Science.gov (United States)

    Basov, A A; Bykov, I M

    2013-01-01

    The effect of nutritional correction (a diet high in foods with antioxidant content) on blood parameters in laboratory animals with metabolic disorders associated with oxidative stress has been studied. In experimental models of laboratory animals (male rabbits weighing 3.5-4.0 kg, n = 40) with purulent septic diseases it has been demonstrated that the use of nutritive correction (replacement of 100 g of the cereal mixture through day on a mixture of cabbage 50 g, carrots 50 g, beet 25 g, apple 25 g, kiwi 10 g and garnet 10 g per 1 rabbit) is not inferior to its efficiency of glutathione use (2 g per day). The use of these antioxidants in laboratory animals significantly reduced the phenomenon of oxidative stress on the 5th day: blood antioxidant capacity significantly increased by 14.9 and 26.6%, and the area of the flash of luminol-dependent H2O2-induced chemiluminescence of blood plasma reduced by 44.2 and 48.6% in the experimental groups receiving respectively nutritive correction and glutathione. The low-molecula level of blood antioxidant capacity was restored and the balance of the activity of superoxide dismutase (decrease) and catalase (increase) was achieved on the 10th day of the experiment. These figures significantly (p < 0.05) differed from than in the group of animals receiving no antioxidant correction. The latter studied parameters of prooxidant-antioxidant system reached values comparable with those in intact animals (n = 10) only on the 30th day, confirming the advisability of appointing a complex antioxidant therapy.

  16. Experimental analysis of nonlinear problems in solid mechanics

    International Nuclear Information System (INIS)

    1982-01-01

    The booklet presents abstracts of papers from the Euromech Colloqium No. 152 held from Sept. 20th to 24th, 1982 in Wuppertal, Federal Republic of Germany. All the papers are dealing with Experimental Analysis of Nonlinear Problems in Solid Mechanics. (RW)

  17. The Animal Model of Spinal Cord Injury as an Experimental Pain Model

    OpenAIRE

    Nakae, Aya; Nakai, Kunihiro; Yano, Kenji; Hosokawa, Ko; Shibata, Masahiko; Mashimo, Takashi

    2011-01-01

    Pain, which remains largely unsolved, is one of the most crucial problems for spinal cord injury patients. Due to sensory problems, as well as motor dysfunctions, spinal cord injury research has proven to be complex and difficult. Furthermore, many types of pain are associated with spinal cord injury, such as neuropathic, visceral, and musculoskeletal pain. Many animal models of spinal cord injury exist to emulate clinical situations, which could help to determine common mechanisms of patholo...

  18. DOES AEROBIC EXERCISE TRAINING PROMOTE CHANGES IN STRUCTURAL AND BIOMECHANICAL PROPERTIES OF THE TENDONS IN EXPERIMENTAL ANIMALS? A SYSTEMATIC REVIEW

    Directory of Open Access Journals (Sweden)

    Márcio A. Bezerra

    2012-11-01

    Full Text Available To develop a systematic review to evaluate, through the best scientific evidence available, the effectiveness of aerobic exercise in improving the biomechanical characteristics of tendons in experimental animals. Two independent assessors conducted a systematic search in the databases Medline/PUBMED and Lilacs/BIREME, using the following descriptors of Mesh in animal models. The ultimate load of traction and the elastic modulus tendon were used as primary outcomes and transverse section area, ultimate stress and tendon strain as secondary outcomes. The assessment of risk of bias in the studies was carried out using the following methodological components: light/dark cycle, temperature, nutrition, housing, research undertaken in conjunction with an ethics committee, randomization, adaptation of the animals to the training and preparation for the mechanical test. Eight studies, comprising 384 animals, were selected; it was not possible to combine them into one meta-analysis due to the heterogeneity of the samples. There was a trend to increasing ultimate load without changes in the other outcomes studied. Only one study met more than 80% of the quality criteria. Physical training performed in a structured way with imposition of overloads seems to be able to promote changes in tendon structure of experimental models by increasing the ultimate load supported. However, the results of the influence of exercise on the elastic modulus parameters, strain, transverse section area and ultimate stress, remain controversial and inconclusive. Such a conclusion must be evaluated with reservation as there was low methodological control in the studies included in this review.

  19. From experimental zoology to big data: Observation and integration in the study of animal development.

    Science.gov (United States)

    Bolker, Jessica; Brauckmann, Sabine

    2015-06-01

    The founding of the Journal of Experimental Zoology in 1904 was inspired by a widespread turn toward experimental biology in the 19th century. The founding editors sought to promote experimental, laboratory-based approaches, particularly in developmental biology. This agenda raised key practical and epistemological questions about how and where to study development: Does the environment matter? How do we know that a cell or embryo isolated to facilitate observation reveals normal developmental processes? How can we integrate descriptive and experimental data? R.G. Harrison, the journal's first editor, grappled with these questions in justifying his use of cell culture to study neural patterning. Others confronted them in different contexts: for example, F.B. Sumner insisted on the primacy of fieldwork in his studies on adaptation, but also performed breeding experiments using wild-collected animals. The work of Harrison, Sumner, and other early contributors exemplified both the power of new techniques, and the meticulous explanation of practice and epistemology that was marshaled to promote experimental approaches. A century later, experimentation is widely viewed as the standard way to study development; yet at the same time, cutting-edge "big data" projects are essentially descriptive, closer to natural history than to the approaches championed by Harrison et al. Thus, the original questions about how and where we can best learn about development are still with us. Examining their history can inform current efforts to incorporate data from experiment and description, lab and field, and a broad range of organisms and disciplines, into an integrated understanding of animal development. © 2015 Wiley Periodicals, Inc.

  20. Mechanical properties of jennite: A theoretical and experimental study

    Energy Technology Data Exchange (ETDEWEB)

    Moon, Juhyuk, E-mail: juhyuk.moon@stonybrook.edu [Civil Engineering Program, Department of Mechanical Engineering, Stony Brook University, NY 11794 (United States); Yoon, Seyoon [School of Engineering, Kings College, University of Aberdeen, Aberdeen AB24 3UE (United Kingdom); Monteiro, Paulo J.M. [Department of Civil and Environmental Engineering, University of California, Berkeley, CA 94720 (United States)

    2015-05-15

    The objective of this study is to determine the mechanical properties of jennite. To date, several hypotheses have been proposed to predict the structural properties of jennite. For the first time as reported herein, the isothermal bulk modulus of jennite was measured experimentally. Synchrotron-based high-pressure x-ray diffraction experiments were performed to observe the variation of lattice parameters under pressure. First-principles calculations were applied to compare with the experimental results and predict additional structural properties. Accurately measured isothermal bulk modulus herein (K{sub 0} = 64(2) GPa) and the statistical assessment on experimental and theoretical results suggest reliable mechanical properties of shear and Young's modulus, Poisson's ratio, and elastic tensor coefficients. Determination of these fundamental structural properties is the first step toward greater understanding of calcium–silicate–hydrate, as well as provides a sound foundation for forthcoming atomic level simulations.

  1. Monkeypox disease transmission in an experimental setting: prairie dog animal model.

    Directory of Open Access Journals (Sweden)

    Christina L Hutson

    Full Text Available Monkeypox virus (MPXV is considered the most significant human public health threat in the genus Orthopoxvirus since the eradication of variola virus (the causative agent of smallpox. MPXV is a zoonotic agent endemic to forested areas of Central and Western Africa. In 2003, MPXV caused an outbreak in the United States due to the importation of infected African rodents, and subsequent sequential infection of North American prairie dogs (Cynomys ludovicianus and humans. In previous studies, the prairie dog MPXV model has successfully shown to be very useful for understanding MPXV since the model emulates key characteristics of human monkeypox disease. In humans, percutaneous exposure to animals has been documented but the primary method of human-to-human MPXV transmission is postulated to be by respiratory route. Only a few animal model studies of MPXV transmission have been reported. Herein, we show that MPXV infected prairie dogs are able to transmit the virus to naive animals through multiple transmission routes. All secondarily exposed animals were infected with MPXV during the course of the study. Notably, animals secondarily exposed appeared to manifest more severe disease; however, the disease course was very similar to those of experimentally challenged animals including inappetence leading to weight loss, development of lesions, production of orthopoxvirus antibodies and shedding of similar levels or in some instances higher levels of MPXV from the oral cavity. Disease was transmitted via exposure to contaminated bedding, co-housing, or respiratory secretions/nasal mucous (we could not definitively say that transmission occurred via respiratory route exclusively. Future use of the model will allow us to evaluate infection control measures, vaccines and antiviral strategies to decrease disease transmission.

  2. Biofilms and mechanics: a review of experimental techniques and findings

    International Nuclear Information System (INIS)

    Gordon, Vernita D; Davis-Fields, Megan; Kovach, Kristin; Rodesney, Christopher A

    2017-01-01

    Biofilms are developmentally-dynamic communities of sessile microbes that adhere to each other and, often, to other structures in their environment. The cohesive mechanical forces binding microbes to each other confer mechanical and structural stability on the biofilm and give rise to biofilm viscoelasticity. The adhesive mechanical forces binding microbes to other structures in their environment can promote biofilm initiation and mechanosensing that leads to changes in biological activity. Thus, physical mechanics is intrinsic to characteristics that distinguish biofilms from free-swimming or free-floating microbes in liquid culture. However, very little is known about the specifics of what mechanical traits characterize different types of biofilms at different stages of development. Even less is known about how mechanical inputs impact microbial biology and how microbes can adjust their mechanical coupling to, and interaction with, their environment. These knowledge gaps arise, in part, from the challenges associated with experimental measurements of microbial and biofilm biomechanics. Here, we review extant experimental techniques and their most-salient findings to date. At the end of this review we indicate areas where significant advances in the state-of-the art are heading. (topical review)

  3. Biofilms and mechanics: a review of experimental techniques and findings

    Science.gov (United States)

    Gordon, Vernita D.; Davis-Fields, Megan; Kovach, Kristin; Rodesney, Christopher A.

    2017-06-01

    Biofilms are developmentally-dynamic communities of sessile microbes that adhere to each other and, often, to other structures in their environment. The cohesive mechanical forces binding microbes to each other confer mechanical and structural stability on the biofilm and give rise to biofilm viscoelasticity. The adhesive mechanical forces binding microbes to other structures in their environment can promote biofilm initiation and mechanosensing that leads to changes in biological activity. Thus, physical mechanics is intrinsic to characteristics that distinguish biofilms from free-swimming or free-floating microbes in liquid culture. However, very little is known about the specifics of what mechanical traits characterize different types of biofilms at different stages of development. Even less is known about how mechanical inputs impact microbial biology and how microbes can adjust their mechanical coupling to, and interaction with, their environment. These knowledge gaps arise, in part, from the challenges associated with experimental measurements of microbial and biofilm biomechanics. Here, we review extant experimental techniques and their most-salient findings to date. At the end of this review we indicate areas where significant advances in the state-of-the art are heading.

  4. Mechanical properties of experimental composites with different calcium phosphates fillers.

    Science.gov (United States)

    Okulus, Zuzanna; Voelkel, Adam

    2017-09-01

    Calcium phosphates (CaPs)-containing composites have already shown good properties from the point of view of dental restorative materials. The purpose of this study was to examine the crucial mechanical properties of twelve hydroxyapatite- or tricalcium phosphate-filled composites. The raw and surface-treated forms of both CaP fillers were applied. As a reference materials two experimental glass-containing composites and one commercial dental restorative composite were applied. Nano-hardness, elastic modulus, compressive, flexural and diametral tensile strength of all studied materials were determined. Application of statistical methods (one-way analysis of variance and cluster agglomerative analysis) allowed for assessing the similarities between examined materials according to the values of studied parameters. The obtained results show that in almost all cases the mechanical properties of experimental CaPs-composites are comparable or even better than mechanical properties of examined reference materials. Copyright © 2017 Elsevier B.V. All rights reserved.

  5. Models, simulation, and experimental issues in structural mechanics

    CERN Document Server

    Maceri, Franco; Vairo, Giuseppe

    2017-01-01

    The reader aware in Structural Mechanics will find in this book a source of fruitful knowledge and effective tools useful for imagining, creating, and promoting novel and challenging developments. It addresses a wide range of topics, such as mechanics and geotechnics, vibration and damping, damage and friction, experimental methods, and advanced structural materials. It also discusses analytical, experimental and numerical findings, focusing on theoretical and practical issues, and leading to innovations in the field. Collecting some of the latest results from the Lagrange Laboratory, a European scientific research group, mainly consisting of Italian and French engineers, mechanicians and mathematicians, the book presents the most recent example of the long-term scientific cooperation between well-established French and Italian Mechanics, Mathematics and Engineering Schools. .

  6. [Animal experimental study of compression anastomosis ring for low anterior resection].

    Science.gov (United States)

    Liang, Jian-Wei; Wang, Zheng; Zhang, Xing-Mao; Zhan, Da-Wei; Zhou, Zhi-Xiang

    2011-05-01

    To evaluate the feasibility and safety of nickel-titanium compression anastomosis ring (CAR27) in colorectal anastomosis after low anterior rectal resection in animal models. End-to-end colorectal anastomosis was performed using CAR27 in 6 experimental pigs after resection of the middle and lower third of the rectum. The animals were observed postoperatively for up to 56 days. Five pigs were sacrificed at day 14 and the other at day 56. Distance from anal verge to anastomosis and anastomotic circumference were measured. Histopathologic examination was performed. The median distance from anal verge was 5.3(4-6) cm. No anastomotic leak or other complications were observed. All the pigs recovered and gained weight. In 5 animals sacrificed at day 14, the mean circumference of the anastomosis was 6.8(6.5-7.0) cm, and histopathological examination showed mild inflammatory reaction and fibrosis. In the one sacrificed at day 56, the circumference expanded to 9.3 cm, and no inflammation and fibrosis were observed. Minor adhesion was noticed in only one pig, while smooth and intact serosa in the anastomosis was seen in the rest of the animals. CAR27 is a promising device for mid and low colorectal anastomosis.

  7. Prospects for new information relevant to radiation protection from studies of experimental animals

    International Nuclear Information System (INIS)

    McClellan, R.O.

    1988-01-01

    The theory underlying radiation protection was developed from studies of people, laboratory animals, tissues, cells and macromolecules. Data on people were obtained from opportunistic studies of individuals previously exposed to radiation. Rarely has it been possible to conduct prospective studies of people exposed to known quantities of radiation, which sharply restricts the nature of questions that they can address. In contrast, studies using laboratory animals and simpler biological systems can be designed to address specific questions, using controlled exposure conditions. In-vitro research with macromolecules, cells and tissues leads to understanding normal and disease processes in isolated biological components. Studies of the intact animals provide opportunities to study in vivo interactive mechanisms observed in vitro and their role in development of radiation-induced diseases such as cancer. In the future, studies of intact animals should prove increasingly valuable in linking new knowledge at the subanimal level with the more fragmentary information obtained from direct observations on people. This will provide insight into important issues such as (a) effects of low-level radiation exposures, (b) mechanism of cancer induction at high versus low radiation doses, and (c) influence of factors such as nutrition and exposure to chemicals on radiation-induced cancer. This presentation describes strategies for conducting and integrating results of research using macromolecules, cells, tissues, laboratory animals and people to improve our understanding of radiation-induced cancer. It will also emphasize the problems encountered in studies at all levels of biological organization when the disease is observed in low excess incidence long after exposure to the toxicant

  8. Animal model of atherosclerosis using rabbit experimentally induced by combination of X-ray and hypercholesterolemia

    International Nuclear Information System (INIS)

    Ishiyama, Tomotoshi; Sawai, Takashi; Okuma, Tsuneo; Mori, Shozo

    1995-01-01

    An attempt was made to prepare an animal model of atherosclerosis similar to human lesions. The experimental animals were male Japanese white rabbits weighting about 2 kg. Hypercholesterolemia was experimentally induced by giving a 1% cholesterol diet. Four weeks later, a single dose of 45 Gy was delivered to the femur to produce vascular changes. Soon after irradiation, immunohistochemical examination revealed the adhesion and invasion of macrophages to endothelial cells, followed by accumulation of foam cells and thickness of the intimal plaques. Three months after irradiation, these thickened plaques became fibrotic, calcified, and necrotic. The tunica media was thinned and the internal elastic lamella was destroyed. Irradiated arteries exhibited not only severe narrowing of the lumen but also aneurysmal dilation and the lesions of the irradiated arteries resembled human atherosclerosis. In conclusion, the atherosclerotic model produced by combining experimental hypercholesterolemia and X-ray irradiaiton may serve as a useful model for studies on atherosclerosis because it can be prepared with no need of complicated or time-consuming procedures. (N.K.)

  9. Macroscopic quantum mechanics: theory and experimental concepts of optomechanics

    International Nuclear Information System (INIS)

    Chen Yanbei

    2013-01-01

    Rapid experimental progress has recently allowed the use of light to prepare macroscopic mechanical objects into nearly pure quantum states. This research field of quantum optomechanics opens new doors towards testing quantum mechanics, and possibly other laws of physics, in new regimes. In the first part of this article, I will review a set of techniques of quantum measurement theory that are often used to analyse quantum optomechanical systems. Some of these techniques were originally designed to analyse how a classical driving force passes through a quantum system, and can eventually be detected with an optimal signal-to-noise ratio—while others focus more on the quantum-state evolution of a mechanical object under continuous monitoring. In the second part of this article, I will review a set of experimental concepts that will demonstrate quantum mechanical behaviour of macroscopic objects—quantum entanglement, quantum teleportation and the quantum Zeno effect. Taking the interplay between gravity and quantum mechanics as an example, I will review a set of speculations on how quantum mechanics can be modified for macroscopic objects, and how these speculations—and their generalizations—might be tested by optomechanics. (invited review)

  10. [F18]-FDG imaging of experimental animal tumours using a hybrid gamma-camera

    International Nuclear Information System (INIS)

    Lausson, S.; Maurel, G.; Kerrou, K.; Montravers, F.; Petegnief, Y.; Talbot, J.N.; Fredelizi, D.

    2001-01-01

    Positron emission tomography (PET) has been widely used in clinical studies. This technology permits detection of compounds labelled with positron emitting radionuclides and in particular, [F18]-fluorodeoxyglucose ([F18]-FDG).[F18]-FDG uptake and accumulation is generally related to malignancy; some recent works have suggested the usefulness of PET camera dedicated to small laboratory animals (micro-PET). Our study dealt with the feasibility of [F18]-FDG imaging of malignant tumours in animal models by means of an hybrid camera dedicated for human scintigraphy. We evaluated the ability of coincidence detection emission tomography (CDET) using this hybrid camera to visualize in vivo subcutaneous tumours grafted to mice or rats. P815 murine mastocytoma grafted in syngeneic DBA/2 mice resulted with foci of very high FDG uptake. Tumours with a diameter of only 3 mm were clearly visualized. Medullary thyroid cancer provoked by rMTC 6/23 and CA77 lines in syngeneic Wag/Rij rat was also detected. The differentiated CA77 tumours exhibited avidity for [F18]-FDG and a tumour, which was just palpable (diameter lower than 2 mm), was identified. In conclusion, CDET-FDG is a non-invasive imaging tool which can be used to follow grafted tumours in the small laboratory animal, even when their size is smaller than 1 cm. It has the potential to evaluate experimental anticancer treatments in small series of animals by individual follow-up. It offers the opportunity to develop experimental PET research within a nuclear medicine or biophysics department, the shift to a dedicated micro-PET device being subsequently necessary. It is indeed compulsory to strictly follow the rules for non contamination and disinfection of the hybrid camera. (authors)

  11. Cardiovascular effects of Helichrysum ceres S Moore [Asteraceae] ethanolic leaf extract in some experimental animal paradigms.

    Science.gov (United States)

    Musabayane, Cephas T; Kamadyaapa, Dave R; Gondwe, Mavuto; Moodley, Kogi; Ojewole, John A O

    2008-01-01

    The aim of this study was to examine some in vivo and in vitro cardiovascular effects of Helichrysum ceres leaf ethanolic extract (HCE) in experimental animal paradigms. The acute effects of HCE on blood pressure were studied in anaesthetised normotensive male Wistar rats challenged with intravenous hypotonic saline infusion after a 3.5-hour equilibration for four hours of one-hour control, 1.5-hour treatment and 1.5-hour recovery periods. HCE was added to the infusate during the treatment period. Sub-chronic hypotensive effects of HCE were examined in weanling Dahl saltsensitive (DSS) genetically hypertensive rats, which progressively develop hypertension with age, treated with HCE (80 mg/kg) every third consecutive day for seven weeks. Isolated atrial muscle strips, portal veins and descending thoracic aortic rings of healthy normotensive Wistar rats were used to investigate the vascular effects of HCE. Acute HCE administration caused a significant (p < 0.05) fall in blood pressure in the normotensive anaesthetised Wistar rats. DSS hypertensive rats treated with HCE displayed low arterial blood pressure and heart rate values from weeks five to seven. HCE produced concentrationdependent negative inotropic and chronotropic effects on rat isolated electrically driven left, and spontaneously beating right atrial muscle preparations, respectively. HCE also evoked concentration-dependent relaxation responses of endothelium-intact aortic rings and portal veins isolated from healthy normotensive Wistar rats. The vasorelaxant effects of HCE in intact aortic rings were significantly reduced, but not completely abolished by adding endothelial- derived factor (EDRF) inhibitor, L-NAME, suggesting that the vasorelaxant effect of the extract is mediated via EDRF-dependent and independent mechanisms. The results of the study suggest that the hypotensive action of HCE is elicited, in part, directly by decreasing myocardial contractile performance and total peripheral vascular

  12. Strain preservation of experimental animals: vitrification of two-cell stage embryos for multiple mouse strains.

    Science.gov (United States)

    Eto, Tomoo; Takahashi, Riichi; Kamisako, Tsutomu

    2015-04-01

    Strain preservation of experimental animals is crucial for experimental reproducibility. Maintaining complete animal strains, however, is costly and there is a risk for genetic mutations as well as complete loss due to disasters or illness. Therefore, the development of effective vitrification techniques for cryopreservation of multiple experimental animal strains is important. We examined whether a vitrification method using cryoprotectant solutions, P10 and PEPeS, is suitable for preservation of multiple inbred and outbred mouse strains. First, we investigated whether our vitrification method using cryoprotectant solutions was suitable for two-cell stage mouse embryos. In vitro development of embryos exposed to the cryoprotectant solutions was similar to that of fresh controls. Further, the survival rate of the vitrified embryos was extremely high (98.1%). Next, we collected and vitrified two-cell stage embryos of 14 mouse strains. The average number of embryos obtained from one female was 7.3-33.3. The survival rate of vitrified embryos ranged from 92.8% to 99.1%, with no significant differences among mouse strains. In vivo development did not differ significantly between fresh controls and vitrified embryos of each strain. For strain preservation using cryopreserved embryos, two offspring for inbred lines and one offspring for outbred lines must be produced from two-cell stage embryos collected from one female. The expected number of surviving fetuses obtained from embryos collected from one female of either the inbred or outbred strains ranged from 2.9 to 19.5. The findings of the present study indicated that this vitrification method is suitable for strain preservation of multiple mouse strains. Copyright © 2015 The Authors. Published by Elsevier Inc. All rights reserved.

  13. Harmaline Tremor: Underlying Mechanisms in a Potential Animal Model of Essential Tremor

    Directory of Open Access Journals (Sweden)

    Adrian Handforth

    2012-09-01

    Full Text Available Background: Harmaline and harmine are tremorigenic β-carbolines that, on administration to experimental animals, induce an acute postural and kinetic tremor of axial and truncal musculature. This drug-induced action tremor has been proposed as a model of essential tremor. Here we review what is known about harmaline tremor.Methods: Using the terms harmaline and harmine on PubMed, we searched for papers describing the effects of these β-carbolines on mammalian tissue, animals, or humans.Results: Investigations over four decades have shown that harmaline induces rhythmic burst-firing activity in the medial and dorsal accessory inferior olivary nuclei that is transmitted via climbing fibers to Purkinje cells and to the deep cerebellar nuclei, then to brainstem and spinal cord motoneurons. The critical structures required for tremor expression are the inferior olive, climbing fibers, and the deep cerebellar nuclei; Purkinje cells are not required. Enhanced synaptic norepinephrine or blockade of ionic glutamate receptors suppresses tremor, whereas enhanced synaptic serotonin exacerbates tremor. Benzodiazepines and muscimol suppress tremor. Alcohol suppresses harmaline tremor but exacerbates harmaline-associated neural damage. Recent investigations on the mechanism of harmaline tremor have focused on the T-type calcium channel.Discussion: Like essential tremor, harmaline tremor involves the cerebellum, and classic medications for essential tremor have been found to suppress harmaline tremor, leading to utilization of the harmaline model for preclinical testing of antitremor drugs. Limitations are that the model is acute, unlike essential tremor, and only approximately half of the drugs reported to suppress harmaline tremor are subsequently found to suppress tremor in clinical trials.

  14. Hypoxia and oxidation levels of DNA and lipids in humans and animal experimental models

    DEFF Research Database (Denmark)

    Møller, Peter; Risom, Lotte; Lundby, Carsten

    2008-01-01

    The objective of this review was to evaluate the association between hypoxia and oxidative damage to DNA and lipids. Evaluation criteria encompassed specificity and validation status of the biomarkers, study design, strength of the association, dose-response relationship, biological plausibility......, analogous exposures, and effect modification by intervention. The collective interpretation indicates persuasive evidence from the studies in humans for an association between hypoxia and elevated levels of oxidative damage to DNA and lipids. The levels of oxidatively generated DNA lesions and lipid...... in subjects at high altitude. Most of the animal experimental models should be interpreted with caution because the assays for assessment of lipid peroxidation products have suboptimal validity....

  15. Experimental validation of a new heterogeneous mechanical test design

    Science.gov (United States)

    Aquino, J.; Campos, A. Andrade; Souto, N.; Thuillier, S.

    2018-05-01

    Standard material parameters identification strategies generally use an extensive number of classical tests for collecting the required experimental data. However, a great effort has been made recently by the scientific and industrial communities to support this experimental database on heterogeneous tests. These tests can provide richer information on the material behavior allowing the identification of a more complete set of material parameters. This is a result of the recent development of full-field measurements techniques, like digital image correlation (DIC), that can capture the heterogeneous deformation fields on the specimen surface during the test. Recently, new specimen geometries were designed to enhance the richness of the strain field and capture supplementary strain states. The butterfly specimen is an example of these new geometries, designed through a numerical optimization procedure where an indicator capable of evaluating the heterogeneity and the richness of strain information. However, no experimental validation was yet performed. The aim of this work is to experimentally validate the heterogeneous butterfly mechanical test in the parameter identification framework. For this aim, DIC technique and a Finite Element Model Up-date inverse strategy are used together for the parameter identification of a DC04 steel, as well as the calculation of the indicator. The experimental tests are carried out in a universal testing machine with the ARAMIS measuring system to provide the strain states on the specimen surface. The identification strategy is accomplished with the data obtained from the experimental tests and the results are compared to a reference numerical solution.

  16. Effects of experimental radiotherapy and hyperthermia on tumors and normal tissues in small animals

    International Nuclear Information System (INIS)

    Wondergem, J.

    1985-01-01

    Experiments on responses of tumors, implanted subcutaneously in the leg, to irradiation alone or combined with heat are reported. The influence of factors modifying the fraction of hypoxic cells (e.g. anesthesia of the animal and tumor volume) is also discussed. The radiosensitivity of developing lung tumors was examined for spontaneous as well as for artificial lung metastases. Both experimental tumor models were compared with regard to their value in experimental radiotherapy. Data obtained on the response of artificial metastases and lung tissue to combined treatment with irradiation and several drugs are presented. Data on damage of the mouse foot, as a result of heat and/or irradiation treatments are presented. In particular the influence of thermotolerance on thermal enhancement of the radiation induced skin reaction was studied. Tolerance of the skin of previously irradiated mice to retreatment with irradiation, to hyperthermia alone and combined with X-rays was assessed. (Auth.)

  17. Lignin biodegradation: experimental evidence, molecular, biochemical and physiological mechanisms

    Energy Technology Data Exchange (ETDEWEB)

    Monties, B

    1985-01-01

    A critical review is presented of English, French and some German language literature, mainly from 1983 onwards. It examines experimental evidence on the behaviour as barriers to biodegradation of lignins and phenolic polymers such as tannins and suberins. The different molecular mechanisms of lignolysis by fungi (mainly), actinomycetes and bacteria are examined. A new biochemical approach to the physiological mechanism of regulation of lignolytic activities is suggested based on the discoveries of ligniolytic enzymes: effects of nitrogen, oxygen and substrate are discussed. It is concluded that a better knowledge of the structure and reactivity of phenolic barriers is needed in order to control the process of lignolysis.

  18. The Animal Model of Spinal Cord Injury as an Experimental Pain Model

    Directory of Open Access Journals (Sweden)

    Aya Nakae

    2011-01-01

    Full Text Available Pain, which remains largely unsolved, is one of the most crucial problems for spinal cord injury patients. Due to sensory problems, as well as motor dysfunctions, spinal cord injury research has proven to be complex and difficult. Furthermore, many types of pain are associated with spinal cord injury, such as neuropathic, visceral, and musculoskeletal pain. Many animal models of spinal cord injury exist to emulate clinical situations, which could help to determine common mechanisms of pathology. However, results can be easily misunderstood and falsely interpreted. Therefore, it is important to fully understand the symptoms of human spinal cord injury, as well as the various spinal cord injury models and the possible pathologies. The present paper summarizes results from animal models of spinal cord injury, as well as the most effective use of these models.

  19. The Animal Model of Spinal Cord Injury as an Experimental Pain Model

    Science.gov (United States)

    Nakae, Aya; Nakai, Kunihiro; Yano, Kenji; Hosokawa, Ko; Shibata, Masahiko; Mashimo, Takashi

    2011-01-01

    Pain, which remains largely unsolved, is one of the most crucial problems for spinal cord injury patients. Due to sensory problems, as well as motor dysfunctions, spinal cord injury research has proven to be complex and difficult. Furthermore, many types of pain are associated with spinal cord injury, such as neuropathic, visceral, and musculoskeletal pain. Many animal models of spinal cord injury exist to emulate clinical situations, which could help to determine common mechanisms of pathology. However, results can be easily misunderstood and falsely interpreted. Therefore, it is important to fully understand the symptoms of human spinal cord injury, as well as the various spinal cord injury models and the possible pathologies. The present paper summarizes results from animal models of spinal cord injury, as well as the most effective use of these models. PMID:21436995

  20. Experimental study on synchronization of three coupled mechanical metronomes

    Science.gov (United States)

    Hu, Qiang; Liu, Weiqing; Yang, Hujiang; Xiao, Jinghua; Qian, Xiaolan

    2013-03-01

    In this paper, a CCD acquisition system is set up to explore the dynamics of three coupled mechanical metronomes in order to compensate for the defects of visual observation. The facility is efficient to observe rich dynamics in an experiment, such as phase synchronization, partial phase synchronization and quasi-periodical oscillation, by accurately recording the trajectory of three coupled metronomes. The parameters, e.g., pendulum length and rolling friction are deemed to significantly influence the dynamics of three coupled mechanical metronomes judging from the experimental phenomena. The experimental results are confirmed by the numerical simulation based on the model with different intrinsic frequencies between three metronomes. The metronome and CCD acquisition systems are excellent demonstration apparatuses for a class and an undergraduate physics laboratory.

  1. Experimental study on synchronization of three coupled mechanical metronomes

    International Nuclear Information System (INIS)

    Hu Qiang; Yang Hujiang; Xiao Jinghua; Liu Weiqing; Qian Xiaolan

    2013-01-01

    In this paper, a CCD acquisition system is set up to explore the dynamics of three coupled mechanical metronomes in order to compensate for the defects of visual observation. The facility is efficient to observe rich dynamics in an experiment, such as phase synchronization, partial phase synchronization and quasi-periodical oscillation, by accurately recording the trajectory of three coupled metronomes. The parameters, e.g., pendulum length and rolling friction are deemed to significantly influence the dynamics of three coupled mechanical metronomes judging from the experimental phenomena. The experimental results are confirmed by the numerical simulation based on the model with different intrinsic frequencies between three metronomes. The metronome and CCD acquisition systems are excellent demonstration apparatuses for a class and an undergraduate physics laboratory. (paper)

  2. Experimental study of mechanical properties on spacer in NHR

    International Nuclear Information System (INIS)

    Jiang Yueyuan; Shi Jibing; Xu Yong

    2007-01-01

    The spacer of NHR-200 is composed mainly of the inner, outer and cornual strips which are ranged in egg-crate of 12 x 12-3. First, the pre-distortion of three kinds of three-arc springs on reactor working condition and their related clipping-force ranges are analyzed in this paper. Secondly, the mechanical experiments of 1:1 prototype, such as the load-distortion experiments, which the load and distortion are respectively measured by strain gauge and displacement sensor, of three kinds of springs, rigid supports and the spacers in two different directions are carried out on a special experimental facility. The experimental results show that the spacer can completely meet the design demands of mechanical properties of the fuel assemblies in NHR-200. (authors)

  3. The approval mechanism solves the prisoner's dilemma theoretically and experimentally

    OpenAIRE

    Tatsuyoshi Saijo; Yoshitaka Okano; Takafumi Yamakawa

    2015-01-01

    Consider a situation where players in a prisoner's dilemma game can approve or reject the other's choice such as cooperation or defection. If both players approve the other's choice, the outcome is the one they chose, whereas if either one rejects the other's choice, the outcome is the one when both defect, which we name the approval mechanism herein (this is inspired by the Cold War doctrine of mutually assured destruction). Experimentally, we find that the cooperation rate with the approval...

  4. Investigations in the scintiscanning of joints of animals with experimental and rheumatoid arthritis

    International Nuclear Information System (INIS)

    Hanheide, M.

    1982-01-01

    In 69 guinea pigs with experimental hyperergic arthritis scintiscanning was done to study the course of the inflammation and the deposition of the radionuclides used. During the first days there was an added storage in the inflamed joints of those animals on whom scintiscanning with Tc99m04 had been performed. The accumulation of Tc99m04 in the joints was due to its uptake by synovial tissue and hydrarthrosis as shown by scintiscanning after haemorrhage and perfusion, macroscopic autoradiography and measurements of radioactivity in tissue samples. In 13 animals with rheumatoid arthritis scintiscanning was done twice with Tc99m04 and three times with Tc99mMDP over a period of 13 to 21 months; concomitantly laboratory tests and X-rays were conducted. After Tc99m04 there was a fall in the scintigraphic inflammation index during treatment. That index was determined by forming the quotient from the activities established above the proximal interphalangeal joints and the tibial head. Scintiscanning with Tc99mMDP led to a fall of the inflammation index in animals with classical rheumatoid arthritis, whereas in the ones with probable rheumatoid arthritis it again rose after an initial fall. Unlike x-ray investigation, scintiscanning permits an early diagnosis and course control. (orig.) [de

  5. Ethical issues associated with the use of animal experimentation in behavioral neuroscience research.

    Science.gov (United States)

    Ohl, Frauke; Meijboom, Franck

    2015-01-01

    This chapter briefly explores whether there are distinct characteristics in the field of Behavioral Neuroscience that demand specific ethical reflection. We argue that although the ethical issues in animal-based Behavioral Neuroscience are not necessarily distinct from those in other research disciplines using animal experimentation, this field of endeavor makes a number of specific, ethically relevant, questions more explicit and, as a result, may expose to discussion a series of ethical issues that have relevance beyond this field of science. We suggest that innovative research, by its very definition, demands out-of-the-box thinking. At the same time, standardization of animal models and test procedures for the sake of comparability across experiments inhibits the potential and willingness to leave well-established tracks of thinking, and leaves us wondering how open minded research is and whether it is the researcher's established perspective that drives the research rather than the research that drives the researcher's perspective. The chapter finishes by introducing subsequent chapters of this book volume on Ethical Issues in Behavioral Neuroscience.

  6. Multiscale experimental mechanics of hierarchical carbon-based materials.

    Science.gov (United States)

    Espinosa, Horacio D; Filleter, Tobin; Naraghi, Mohammad

    2012-06-05

    Investigation of the mechanics of natural materials, such as spider silk, abalone shells, and bone, has provided great insight into the design of materials that can simultaneously achieve high specific strength and toughness. Research has shown that their emergent mechanical properties are owed in part to their specific self-organization in hierarchical molecular structures, from nanoscale to macroscale, as well as their mixing and bonding. To apply these findings to manmade materials, researchers have devoted significant efforts in developing a fundamental understanding of multiscale mechanics of materials and its application to the design of novel materials with superior mechanical performance. These efforts included the utilization of some of the most promising carbon-based nanomaterials, such as carbon nanotubes, carbon nanofibers, and graphene, together with a variety of matrix materials. At the core of these efforts lies the need to characterize material mechanical behavior across multiple length scales starting from nanoscale characterization of constituents and their interactions to emerging micro- and macroscale properties. In this report, progress made in experimental tools and methods currently used for material characterization across multiple length scales is reviewed, as well as a discussion of how they have impacted our current understanding of the mechanics of hierarchical carbon-based materials. In addition, insight is provided into strategies for bridging experiments across length scales, which are essential in establishing a multiscale characterization approach. While the focus of this progress report is in experimental methods, their concerted use with theoretical-computational approaches towards the establishment of a robust material by design methodology is also discussed, which can pave the way for the development of novel materials possessing unprecedented mechanical properties. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  7. Annual tendency of research papers used ICR mice as experimental animals in biomedical research fields.

    Science.gov (United States)

    Kim, Ji Eun; Nam, Jung Hoon; Cho, Joon Young; Kim, Kil Soo; Hwang, Dae Youn

    2017-06-01

    Institute of Cancer Research (ICR) mice have been widely used in various research fields including toxicology, oncology, pharmacology, and pharmaceutical product safety testing for decades. However, annual tendency of research papers involving ICR mice in various biomedical fields has not been previously analyzed. In this study, we examined the numbers of papers that used ICR mice as experimental animals in the social science, natural science, engineering, medicine-pharmacy, marine agriculture-fishery, and art-kinesiology fields by analyzing big data. Numbers of ICR mouse-used papers gradually increased from 1961 to 2014, but small decreases were observed in 2015 and 2016. The largest number of ICR-used papers were published in the medicine-pharmacy field, followed by natural science and art-kinesiology fields. There were no ICR mouse-used papers in other fields. Furthermore, ICR mice have been widely employed in cell biology studies within the natural science field as well as in biochemistry and pathology in the medicine-pharmacy field. Few ICR mouse-used papers were published in exercise biochemistry and exercise nutrition in the art-kinesiology field. Regardless in most fields, the total numbers of published papers involving ICR mice were higher in 2014 than in other years, although the numbers in some fields including dentistry, veterinary science, and dermatology were high in 2016. Taken together, the present study shows that various ICR stocks, including Korl:ICR mice, are widely employed as experimental animals in various biomedical research fields.

  8. Ethics and Animal Experimentation in the Laboratory. A Critical Analysis of the Arguments for"Animal Rights"and"Animal Equality"

    OpenAIRE

    Tagha, Yuninui Eric

    2005-01-01

    Growing up as a child, we had a Dog. To us, it was like a means to an end. That is, hunting other animals for food and for protection, with no special care and treatment given to this animal. Butas days passed by I began to witness a wind of change against such actions. I was made to understand that we were committing two crimes-: using the Dog as a means to an end (for hunting and for eating animals). Today almost every newspaper has something to say about the treatment of animals by humans,...

  9. Novel animal model for Achilles tendinopathy: Controlled experimental study of serial injections of collagenase in rabbits.

    Science.gov (United States)

    de Cesar Netto, Cesar; Godoy-Santos, Alexandre Leme; Augusto Pontin, Pedro; Natalino, Renato Jose Mendonça; Pereira, Cesar Augusto Martins; Lima, Francisco Diego de Oliveira; da Fonseca, Lucas Furtado; Staggers, Jackson Rucker; Cavinatto, Leonardo Muntada; Schon, Lew Charles; de Camargo, Olavo Pires; Fernandes, Túlio Diniz

    2018-01-01

    Our goal was to develop a novel technique for inducing Achilles tendinopathy in animal models which more accurately represents the progressive histological and biomechanical characteristic of chronic Achilles tendinopathy in humans. In this animal research study, forty-five rabbits were randomly assigned to three groups and given bilateral Achilles injections. Low dose (LD group) (n = 18) underwent a novel technique with three low-dose (0.1mg) injections of collagenase that were separated by two weeks, the high dose group (HD) (n = 18) underwent traditional single high-dose (0.3mg) injections, and the third group were controls (n = 9). Six rabbits were sacrificed from each experimental group (LD and HD) at 10, 12 and 16 weeks. Control animals were sacrificed after 16 weeks. Histological and biomechanical properties were then compared in all three groups. At 10 weeks, Bonar score and tendon cross sectional area was highest in HD group, with impaired biomechanical properties compared to LD group. At 12 weeks, Bonar score was higher in LD group, with similar biomechanical findings when compared to HD group. After 16 weeks, Bonar score was significantly increased for both LD group (11,8±2,28) and HD group (5,6±2,51), when compared to controls (2±0,76). LD group showed more pronounced histological and biomechanical findings, including cross sectional area of the tendon, Young's modulus, yield stress and ultimate tensile strength. In conclusion, Achilles tendinopathy in animal models that were induced by serial injections of low-dose collagenase showed more pronounced histological and biomechanical findings after 16 weeks than traditional techniques, mimicking better the progressive and chronic characteristic of the tendinopathy in humans.

  10. COMPARISON OF ANTI - INFLAMMATORY ACTIVITY OF ALPINIA GALANGAL IN THREE EXPERIMENTAL ANIMAL MODELS

    Directory of Open Access Journals (Sweden)

    Venuturumilli Lakshmi

    2015-05-01

    Full Text Available Inflammation is not a disease but a non - specific response of the body defence 1 . Anti - inflammatory drugs have become popular because of their ability in controlling the inflammatory reaction and mitigating the suffering in such clinical situations. Edema represents the early phase of inflammation. 2 In the present study acute and subacute experimental methods were compared with standard drug Indomethacin. R at hind paw edema, formalin induced peritonitis in mice were used as acute methods, paper disc induced granuloma in rats was used as subacute method. Institutional animal ethics committee permission was taken for all the methods as per CPCSEA guide lines. Inflammation was induced by the following 3 methods: i Hind paw edema was produced by sub plantar injection of 0.1ml of1% carrageenin 3 and paw volume was measured by digital plethysmometer at 0, 3hours. ii Intraperitoneal injection of 1.5% formalin 3 was given to albino mice in peritonitis method and ascitic fluid was measured after 6hours by sacrificing the animals. iii Under ether anesthesia, sterilized &weighed paper discs were implanted subcutaneously in each axilla and groin of male wistar rats sutur ed under sterilized conditions in granuloma 4 method. The discs were cleared of extraneous tissue, dried and weighed on the 5 th day by sacrificing the animals. In all the methods 6 animals in each group (test, standard and control were taken. Results were tabulated in each method separately and statistical analysis was done by student t test. P value < 0.05 considered significant. Percentage inhibition in each method was calculated.

  11. They see a rat, we seek a cure for diseases: the current status of animal experimentation in medical practice.

    Science.gov (United States)

    Kehinde, Elijah O

    2013-01-01

    The objective of this review article was to examine current and prospective developments in the scientific use of laboratory animals, and to find out whether or not there are still valid scientific benefits of and justification for animal experimentation. The PubMed and Web of Science databases were searched using the following key words: animal models, basic research, pharmaceutical research, toxicity testing, experimental surgery, surgical simulation, ethics, animal welfare, benign, malignant diseases. Important relevant reviews, original articles and references from 1970 to 2012 were reviewed for data on the use of experimental animals in the study of diseases. The use of laboratory animals in scientific research continues to generate intense public debate. Their use can be justified today in the following areas of research: basic scientific research, use of animals as models for human diseases, pharmaceutical research and development, toxicity testing and teaching of new surgical techniques. This is because there are inherent limitations in the use of alternatives such as in vitro studies, human clinical trials or computer simulation. However, there are problems of transferability of results obtained from animal research to humans. Efforts are on-going to find suitable alternatives to animal experimentation like cell and tissue culture and computer simulation. For the foreseeable future, it would appear that to enable scientists to have a more precise understanding of human disease, including its diagnosis, prognosis and therapeutic intervention, there will still be enough grounds to advocate animal experimentation. However, efforts must continue to minimize or eliminate the need for animal testing in scientific research as soon as possible. © 2013 S. Karger AG, Basel.

  12. Building foundations for transcatheter intervascular anastomoses: 3D anatomy of the great vessels in large experimental animals

    NARCIS (Netherlands)

    Sizarov, Aleksander; de Bakker, Bernadette S.; Klein, Karina; Ohlerth, Stefanie

    2014-01-01

    To provide comprehensive illustrations of anatomy of the relevant vessels in large experimental animals in an interactive format as preparation for developing an effective and safe transcatheter technique of aortopulmonary and bidirectional cavopulmonary intervascular anastomoses. Computed

  13. Compliance of the legal treatment of experimental animals in Serbian legislation with the legislation of the European Union

    Directory of Open Access Journals (Sweden)

    Vidić-Trninić Jelena

    2013-01-01

    Full Text Available The author focuses on compliance of the legal treatment of experimental animals in Serbian law with the provisions of the European legislation. Analysing, on one hand, the treatment that experimental animals have under the law of European Union, and on the other hand, the treatment that they have in the law of Serbia, in accordance with the relevant acts and subordinate legislation acts, this article seeks to answer the question whether the degree of legal protection of experimental animals in domestic law is satisfactory, as well as whether and to what extent the relevant national legislation complies with the European standards. At the same time, the article attempts to point out the appropriate measures necessary to be taken in the future in order to achieve as high quality and comprehensive protection of experimental animals as possible in Serbian law.

  14. Experimental psychiatric illness and drug abuse models: from human to animal, an overview.

    Science.gov (United States)

    Edwards, Scott; Koob, George F

    2012-01-01

    Preclinical animal models have supported much of the recent rapid expansion of neuroscience research and have facilitated critical discoveries that undoubtedly benefit patients suffering from psychiatric disorders. This overview serves as an introduction for the following chapters describing both in vivo and in vitro preclinical models of psychiatric disease components and briefly describes models related to drug dependence and affective disorders. Although there are no perfect animal models of any psychiatric disorder, models do exist for many elements of each disease state or stage. In many cases, the development of certain models is essentially restricted to the human clinical laboratory domain for the purpose of maximizing validity, whereas the use of in vitro models may best represent an adjunctive, well-controlled means to model specific signaling mechanisms associated with psychiatric disease states. The data generated by preclinical models are only as valid as the model itself, and the development and refinement of animal models for human psychiatric disorders continues to be an important challenge. Collaborative relationships between basic neuroscience and clinical modeling could greatly benefit the development of new and better models, in addition to facilitating medications development.

  15. Induction of a chronic myocardial infarction in the laboratory animal - experimental model

    Science.gov (United States)

    POP, IONEL CIPRIAN; GRAD, NICOLAE-OVIDIU; PESTEAN, COSMIN; TAULESCU, MARIAN; MIRCEAN, MIRCEA; MIRONIUC, ION-AUREL

    2013-01-01

    Introduction Ischemic heart disease is a major public health problem in western countries. Appropriate animal experimental models of chronic myocardial infarction is an essential first step in order to investigate and develop new therapeutic interventions. Aim The aim of this study was to find an optimal place for a coronary artery ligation to induce an optimal chronic myocardial infarction and also a new heart approach that will not require oro-tracheal intubation. Material and methods To achieve these goals we used a group of rabbits and after induction of anesthesia and cardiac exposure by rib osteotomy (rib III, IV and V) at the costo-sternal junction level on the right side we performed three different left anterior descending artery (LAD) ligation at different distances (5, 10 and 15 mm) in relation to the apex. Thirty days after the acute myocardial infarction, we correlated laboratory investigations (serology, ECG, cardiac ultrasound) with histopathological findings. Results Heart approach achieved by rib osteotomy (rib III, IV and V) at the costo-sternal junction level on the right side, maintains the integrity of the ribcage, allowing it to take part in respiratory movements and the animal model does not need oro-tracheal intubation. Ligation of LAD at 15 mm from the apex was incompatible with life; ligation of LAD at 5 mm from the apex does not achieved transmural myocardial infarction and ligation of LAD at 10 mm from the apex achieved a transmural myocardial infarction of the left ventricle which also involved the distal part of the interventricular septum. Conclusion Ligation of LAD at 10 mm from the apex achieved a transmural myocardial infarction of the left ventricle, is in an easily accessible area from technical point of view, it is sufficiently expanded to induce hemodynamic effects that can be quantified with paraclinical examination and also it is compatible with the experimental animal life. If the heart is approached by rib III, IV and V

  16. A cyber-physical approach to experimental fluid mechanics

    Science.gov (United States)

    Mackowski, Andrew Williams

    This Thesis documents the design, implementation, and use of a novel type of experimental apparatus, termed Cyber-Physical Fluid Dynamics (CPFD). Unlike traditional fluid mechanics experiments, CPFD is a general-purpose technique that allows one to impose arbitrary forces on an object submerged in a fluid. By combining fluid mechanics with robotics, we can perform experiments that would otherwise be incredibly difficult or time-consuming. More generally, CPFD allows a high degree of automation and control of the experimental process, allowing for much more efficient use of experimental facilities. Examples of CPFD's capabilites include imposing a gravitational force in the horizontal direction (allowing a test object to "fall" sideways in a water channel), simulating nonlinear springs for a vibrating fluid-structure system, or allowing a self-propelled body to move forward under its own force. Because experimental parameters (including forces and even the mass of the test object) are defined in software, one can define entire ensembles of experiments to run autonomously. CPFD additionally integrates related systems such as water channel speed control, LDV flow speed measurements, and PIV flowfield measurements. The end result is a general-purpose experimental system that opens the door to a vast array of fluid-structure interaction problems. We begin by describing the design and implementation of CPFD, the heart of which is a high-performance force-feedback control system. Precise measurement of time-varying forces (including removing effects of the test object's inertia) is more critical here than in typical robotic force-feedback applications. CPFD is based on an integration of ideas from control theory, fluid dynamics, computer science, electrical engineering, and solid mechanics. We also describe experiments using the CPFD experimental apparatus to study vortex-induced vibration (VIV) and oscillating-airfoil propulsion. We show how CPFD can be used to simulate

  17. Elucidating Grinding Mechanism by Theoretical and Experimental Investigations

    Directory of Open Access Journals (Sweden)

    AMM Sharif Ullah

    2018-02-01

    Full Text Available Grinding is one of the essential manufacturing processes for producing brittle or hard materials-based precision parts (e.g., optical lenses. In grinding, a grinding wheel removes the desired amount of material by passing the same area on the workpiece surface multiple times. How the topography of a workpiece surface evolves with these passes is thus an important research issue, which has not yet been addressed elaborately. The present paper tackles this issue from both the theoretical and the experimental points of view. In particular, this paper presents the results of experimental and theoretical investigations on the multi-pass surface grinding operations where the workpiece surface is made of glass and the grinding wheel consists of cBN abrasive grains. Both investigations confirm that a great deal of stochasticity is involved in the grinding mechanism, and the complexity of the workpiece surface gradually increases along with the number of passes.

  18. Elucidating Grinding Mechanism by Theoretical and Experimental Investigations.

    Science.gov (United States)

    Ullah, Amm Sharif; Caggiano, Alessandra; Kubo, Akihiko; Chowdhury, M A K

    2018-02-09

    Grinding is one of the essential manufacturing processes for producing brittle or hard materials-based precision parts (e.g., optical lenses). In grinding, a grinding wheel removes the desired amount of material by passing the same area on the workpiece surface multiple times. How the topography of a workpiece surface evolves with these passes is thus an important research issue, which has not yet been addressed elaborately. The present paper tackles this issue from both the theoretical and the experimental points of view. In particular, this paper presents the results of experimental and theoretical investigations on the multi-pass surface grinding operations where the workpiece surface is made of glass and the grinding wheel consists of cBN abrasive grains. Both investigations confirm that a great deal of stochasticity is involved in the grinding mechanism, and the complexity of the workpiece surface gradually increases along with the number of passes.

  19. Grading Gradients: Evaluating Evidence for Time-dependent Memory Reorganization in Experimental Animals

    Directory of Open Access Journals (Sweden)

    Katherine G. Akers

    2009-01-01

    Full Text Available In humans, hippocampal damage typically produces temporally graded retrograde amnesia, with relative sparing of remote memories compared to recent memories. This observation led to the idea that as memories age, they are reorganized in a time-dependent manner. Here, we evaluate evidence for time-dependent memory reorganization in animal models. We conclude that, although hippocampal lesions may not always produce temporal gradients under all conditions, studies using alternate experimental approaches consistently support the idea that memories reorganize over time—becoming less dependent on the hippocampus and more dependent on a cortical network. We further speculate on the processes that drive memory reorganization such as sleep, memory reactivation, synaptic plasticity, and neurogenesis.

  20. Vivisecting Major: a Victorian gentleman scientist defends animal experimentation, 1876-1885.

    Science.gov (United States)

    Boddice, Rob

    2011-06-01

    Through an investigation of the public, professional, and private life of the Darwinian disciple George John Romanes, this essay seeks a better understanding of the scientific motivations for defending the practice of vivisection at the height of the controversy in late Victorian Britain. Setting aside a historiography that has tended to focus on the arguments of antivivisectionists, it reconstructs the viewpoint of the scientific community through an examination of Romanes's work to help orchestrate the defense of animal experimentation. By embedding his life in three complicatedly overlapping networks-the world of print, interpersonal communications among an increasingly professionalized body of scientific men, and the intimacies of private life-the essay uses Romanes as a lens with which to focus the physiological apprehension of the antivivisection movement. It is a story of reputation, self-interest, and affection.

  1. Manual versus mechanical cardiopulmonary resuscitation. An experimental study in pigs

    Directory of Open Access Journals (Sweden)

    Wohlfart Björn

    2010-10-01

    Full Text Available Abstract Background Optimal manual closed chest compressions are difficult to give. A mechanical compression/decompression device, named LUCAS, is programmed to give compression according to the latest international guidelines (2005 for cardiopulmonary resuscitation (CPR. The aim of the present study was to compare manual CPR with LUCAS-CPR. Methods 30 kg pigs were anesthetized and intubated. After a base-line period and five minutes of ventricular fibrillation, manual CPR (n = 8 or LUCAS-CPR (n = 8 was started and run for 20 minutes. Professional paramedics gave manual chest compression's alternating in 2-minute periods. Ventilation, one breath for each 10 compressions, was given to all animals. Defibrillation and, if needed, adrenaline were given to obtain a return of spontaneous circulation (ROSC. Results The mean coronary perfusion pressure was significantly (p Conclusions LUCAS-CPR gave significantly higher coronary perfusion pressure and significantly fewer rib fractures than manual CPR in this porcine model.

  2. Experimental Assessment of Mechanical Night Ventilation on Inner Wall Surfaces

    DEFF Research Database (Denmark)

    Ji, Wenhui; Heiselberg, Per Kvols; Wang, Houhua

    2016-01-01

    The cooling potential of night ventilation largely depends on the heat exchange at the internal room surfaces. During night time, increased heat transfer on a vertical wall is expected due to cool supply air that flows along the internal wall surface from the top of the wall. This paper presents ...... an experimental study of the cooling of wall surfaces in a test room by mechanical night-time ventilation. Significant improvement of indoor thermal environment is presented resulting from the enhanced internal convection heat transfer....

  3. 2013 Annual Conference on Experimental and Applied Mechanics

    CERN Document Server

    Casem, Dan; Kimberley, Jamie; Barthelat, François; Zavattieri, Pablo; Antoun, Bonnie; Qi, H; Hall, Richard; Tandon, G; Lu, Hongbing; Lu, Charles; Furmanski, Jevan; Amirkhizi, Alireza; Korach, Chad; Prorok, Barton; Grande-Allen, K; III, Gordon; Prorok, Barton; Starman, LaVern; Furlong, Cosme; Tandon, G; Tekalur, Srinivasan; Ralph, Carter; Sottos, Nancy; Blaiszik, Benjamin; Jay, Carroll; Rossi, Marco; Sasso, Marco; Connesson, Nathanael; Singh, Raman; DeWald, Adrian; Backman, David; Gloeckner, Paul; Jin, Helena; Sciammarella, Cesar; Yoshida, Sanichiro; Lamberti, Luciano; Vol.1 Dynamic Behavior of Materials; Vol.2 Challenges In Mechanics of Time-Dependent Materials and Processes in Conventional and Multifunctional Materials; Vol.3 Advancement of Optical Methods in Experimental Mechanics; Vol.4 Mechanics of Biological Systems and Materials; Vol.5 MEMS and Nanotechnology; Vol.6 Experimental Mechanics of Composite, Hybrid, and Multifunctional Materials; Vol.7 Fracture and Fatigue; Vol.8 Residual Stress, Thermomechanics & Infrared Imaging, Hybrid Techniques and Inverse Problems; SEM 2013

    2014-01-01

    This critical collection examines a range of topics in fracture and fatigue, including environmental and loading effects in fracture and fatigue and DIC and fracture, as presented in early findings and case studies from the Proceedings of the 2013 Annual Conference on Experimental and Applied Mechanics. The collection includes papers in the following general technical research areas: • Microstructural Effects in Fatigue & Fracture • Fracture of Interfaces • Fracture of Composites and Interface Cracks • Fatigue & Fracture: Environmental & Loading Eff ects • Fracture & Digital Image Correlation Fracture and Fatigue

  4. Animal experimental investigations of the problem of the decorporation of radioactive metal ions

    International Nuclear Information System (INIS)

    Berner, W.

    1973-01-01

    Basically, it is possible to reduce the radiation exposure by excretion intensification of incorporated radioactive materials. Chelate agents have proved to be particularly effective for the accelerated elimination of radioactive metal ions. The kinetics of the distribution and excretion of 57 CoCl 2 , 65 ZnCl 2 and 203 HgCl 2 on the rat under the influence of the chelating agent penicillamin (D-ββ-dimethylcystein) was investigated and the reduction of the radiation exposure in man was calculated from the animal-experimentally gained data. At various times after the incorporation of metal ions, the whole body radioactivity and, after killing the animals, the radioactivity of the organs liver, kidney, spleen, skeleton, muscles and blood, were measured. From the course of the measured radioactivities with time, the biokinetic data of the radioactive metal ions (effective half-lives, selection factors and their components) were determined by means of regression analyses. The chelating agent was applied at different times before or after incorporation of the radioactive metal ions. (EK/LH) [de

  5. Sildenafil Can Affect Innate and Adaptive Immune System in Both Experimental Animals and Patients.

    Science.gov (United States)

    Kniotek, Monika; Boguska, Agnieszka

    2017-01-01

    Sildenafil, a type 5 phosphodiesterase inhibitor (PDE5-I), is primarily used for treating erectile dysfunction. Sildenafil inhibits the degradation of cyclic guanosine monophosphate (cGMP) by competing with cGMP for binding site of PDE5. cGMP is a secondary messenger activating protein kinases and a common regulator of ion channel conductance, glycogenolysis, and cellular apoptosis. PDE5 inhibitors (PDE-Is) found application in cardiology, nephrology, urology, dermatology, oncology, and gynecology. Positive result of sildenafil treatment is closely connected with its immunomodulatory effects. Sildenafil influences angiogenesis, platelet activation, proliferation of regulatory T cells, and production of proinflammatory cytokines and autoantibodies. Sildenafil action in humans and animals appears to be different. Surprisingly, it also acts differently in males and females organisms. Although the immunomodulatory effects of PDE5 inhibitors appear to be promising, none of them reached the point of being tested in clinical trials. Data on the influence of selective PDE5-Is on the human immune system are limited. The main objective of this review is to discuss the immunomodulatory effects of sildenafil in both patients and experimental animals. This is the first review of the current state of knowledge about the effects of sildenafil on the immune system.

  6. An experimental test on large animals of MCNP application for whole body counting

    International Nuclear Information System (INIS)

    Borisov, N.; Yatsenko, V.; Kochetkov, O.; Gusev, I.; Vlasov, P.; Kalistratova, V.; Nisimov, P.; Levochkin, F.; Borovkov, M.; Stolyarov, V.; Tsedish, S.; Tyurin, I.; Franck, D.; Carlan, L. de

    2005-01-01

    Measurements of actinide body burden using whole body counting spectrometry is hampered due to intensive absorption of γ-rays inside the patient's body, which depends on the anatomy of a patient. To establish the correspondence between pulse-height-spectra intensity and radionuclide activity, Monte Carlo calculations are widely used. For such calculations, the radiation transport geometry is usually described in terms of small rectangular boxes (voxels) retrieved from computed tomography or magnetic resonance images. The software for Monte Carlo-assisted calibration of whole body counting, which performs automatic creation of individual MCNP voxel phantoms, was checked in a quasi-in vivo experiment on large animals. During the experiment, pigs of 35-40 kg body mass were used as phantoms for measurement of actinides body burden. 241 Am was administered (via injection of a radioactive solution or via implantation of plastic capsules containing the radioactive material) into the lungs of pigs. The pigs were measured using the pure germanium low-energy γ-spectrometers. The images of animals were obtained using the computed tomography machine. On the base of these tomograms, MCNP4c2 calculations were done to obtain the pulse-height-spectra of the whole body counters. The experimental results were reproduced in calculations with error of less than 30% for 241 Am administered via injection and less than 10% for 241 Am administered inside the capsules. (authors)

  7. The difficult relationship between occlusal interferences and temporomandibular disorder - insights from animal and human experimental studies.

    Science.gov (United States)

    Xie, Q; Li, X; Xu, X

    2013-04-01

    The aetiology of temporomandibular disorder (TMD) is multifactorial, and numerous studies have addressed that occlusion may be of great importance. However, whether occlusion plays a crucial role in the pathogenesis of TMD remains controversial. Study designs utilising animal models have been used to study the effects of artificial occlusal alterations. Experimental traumatic occlusion affects blood flow in the temporomandibular joint and results in changes in the condylar cartilage, and artificial occlusal interference induces masticatory muscle nociceptive responses that are associated with peripheral sensitisation and lead to central sensitisation, which maintains masticatory muscle hyperalgesia. The possibility that occlusal interference results in TMD has been investigated in humans using a double-blind randomised design. Subjects without a history of TMD show fairly good adaptation to interferences. In contrast, subjects with a history of TMD develop a significant increase in clinical signs and self-report stronger symptoms (occlusal discomfort and chewing difficulties) in response to interferences. Meanwhile, psychological factors appear meaningful for symptomatic responses to artificial interferences in subjects with a history of TMD. Thus, individual differences in vulnerability to occlusal interferences do exist. Although there are advantages and disadvantages to using human and animal occlusal interference models, these approaches are indispensable for discovering the role of occlusion in TMD pathogenesis. © 2013 Blackwell Publishing Ltd.

  8. Innovativeness as an emergent property: a new alignment of comparative and experimental research on animal innovation.

    Science.gov (United States)

    Griffin, Andrea S

    2016-03-19

    Innovation and creativity are key defining features of human societies. As we face the global challenges of the twenty-first century, they are also facets upon which we must become increasingly reliant. But what makes Homo sapiens so innovative and where does our high innovation propensity come from? Comparative research on innovativeness in non-human animals allows us to peer back through evolutionary time and investigate the ecological factors that drove the evolution of innovativeness, whereas experimental research identifies and manipulates underpinning creative processes. In commenting on the present theme issue, I highlight the controversies that have typified this research field and show how a paradigmatic shift in our thinking about innovativeness will contribute to resolving these tensions. In the past decade, innovativeness has been considered by many as a trait, a direct product of cognition, and a direct target of selection. The evidence I review here suggests that innovativeness will be hereon viewed as one component, or even an emergent property of a larger array of traits, which have evolved to deal with environmental variation. I illustrate how research should capitalize on taxonomic diversity to unravel the full range of psychological processes that underpin innovativeness in non-human animals. © 2016 The Author(s).

  9. Measuring reinforcement learning and motivation constructs in experimental animals: relevance to the negative symptoms of schizophrenia

    Science.gov (United States)

    Markou, Athina; Salamone, John D.; Bussey, Timothy; Mar, Adam; Brunner, Daniela; Gilmour, Gary; Balsam, Peter

    2013-01-01

    The present review article summarizes and expands upon the discussions that were initiated during a meeting of the Cognitive Neuroscience Treatment Research to Improve Cognition in Schizophrenia (CNTRICS; http://cntrics.ucdavis.edu). A major goal of the CNTRICS meeting was to identify experimental procedures and measures that can be used in laboratory animals to assess psychological constructs that are related to the psychopathology of schizophrenia. The issues discussed in this review reflect the deliberations of the Motivation Working Group of the CNTRICS meeting, which included most of the authors of this article as well as additional participants. After receiving task nominations from the general research community, this working group was asked to identify experimental procedures in laboratory animals that can assess aspects of reinforcement learning and motivation that may be relevant for research on the negative symptoms of schizophrenia, as well as other disorders characterized by deficits in reinforcement learning and motivation. The tasks described here that assess reinforcement learning are the Autoshaping Task, Probabilistic Reward Learning Tasks, and the Response Bias Probabilistic Reward Task. The tasks described here that assess motivation are Outcome Devaluation and Contingency Degradation Tasks and Effort-Based Tasks. In addition to describing such methods and procedures, the present article provides a working vocabulary for research and theory in this field, as well as an industry perspective about how such tasks may be used in drug discovery. It is hoped that this review can aid investigators who are conducting research in this complex area, promote translational studies by highlighting shared research goals and fostering a common vocabulary across basic and clinical fields, and facilitate the development of medications for the treatment of symptoms mediated by reinforcement learning and motivational deficits. PMID:23994273

  10. Measuring reinforcement learning and motivation constructs in experimental animals: relevance to the negative symptoms of schizophrenia.

    Science.gov (United States)

    Markou, Athina; Salamone, John D; Bussey, Timothy J; Mar, Adam C; Brunner, Daniela; Gilmour, Gary; Balsam, Peter

    2013-11-01

    The present review article summarizes and expands upon the discussions that were initiated during a meeting of the Cognitive Neuroscience Treatment Research to Improve Cognition in Schizophrenia (CNTRICS; http://cntrics.ucdavis.edu) meeting. A major goal of the CNTRICS meeting was to identify experimental procedures and measures that can be used in laboratory animals to assess psychological constructs that are related to the psychopathology of schizophrenia. The issues discussed in this review reflect the deliberations of the Motivation Working Group of the CNTRICS meeting, which included most of the authors of this article as well as additional participants. After receiving task nominations from the general research community, this working group was asked to identify experimental procedures in laboratory animals that can assess aspects of reinforcement learning and motivation that may be relevant for research on the negative symptoms of schizophrenia, as well as other disorders characterized by deficits in reinforcement learning and motivation. The tasks described here that assess reinforcement learning are the Autoshaping Task, Probabilistic Reward Learning Tasks, and the Response Bias Probabilistic Reward Task. The tasks described here that assess motivation are Outcome Devaluation and Contingency Degradation Tasks and Effort-Based Tasks. In addition to describing such methods and procedures, the present article provides a working vocabulary for research and theory in this field, as well as an industry perspective about how such tasks may be used in drug discovery. It is hoped that this review can aid investigators who are conducting research in this complex area, promote translational studies by highlighting shared research goals and fostering a common vocabulary across basic and clinical fields, and facilitate the development of medications for the treatment of symptoms mediated by reinforcement learning and motivational deficits. Copyright © 2013 Elsevier

  11. Experimental approach and micro-mechanical modeling of the mechanical behavior of irradiated zirconium alloys

    International Nuclear Information System (INIS)

    Onimus, F.

    2003-12-01

    Zirconium alloys cladding tubes containing nuclear fuel of the Pressurized Water Reactors constitute the first safety barrier against the dissemination of radioactive elements. Thus, it is essential to predict the mechanical behavior of the material in-reactor conditions. This study aims, on the one hand, to identify and characterize the mechanisms of the plastic deformation of irradiated zirconium alloys and, on the other hand, to propose a micro-mechanical modeling based on these mechanisms. The experimental analysis shows that, for the irradiated material, the plastic deformation occurs by dislocation channeling. For transverse tensile test and internal pressure test this channeling occurs in the basal planes. However, for axial tensile test, the study revealed that the plastic deformation also occurs by channeling but in the prismatic and pyramidal planes. In addition, the study of the macroscopic mechanical behavior, compared to the deformation mechanisms observed by TEM, suggested that the internal stress is higher in the case of irradiated material than in the case of non-irradiated material, because of the very heterogeneous character of the plastic deformation. This analysis led to a coherent interpretation of the mechanical behavior of irradiated materials, in terms of deformation mechanisms. The mechanical behavior of irradiated materials was finally modeled by applying homogenization methods for heterogeneous materials. This model is able to reproduce adequately the mechanical behavior of the irradiated material, in agreement with the TEM observations. (author)

  12. Demystifying animal 'personality' (or not): why individual variation matters to experimental biologists.

    Science.gov (United States)

    Roche, Dominique G; Careau, Vincent; Binning, Sandra A

    2016-12-15

    Animal 'personality', defined as repeatable inter-individual differences in behaviour, is a concept in biology that faces intense controversy. Critics argue that the field is riddled with terminological and methodological inconsistencies and lacks a sound theoretical framework. Nevertheless, experimental biologists are increasingly studying individual differences in physiology and relating these to differences in behaviour, which can lead to fascinating insights. We encourage this trend, and in this Commentary we highlight some of the benefits of estimating variation in (and covariation among) phenotypic traits at the inter- and intra-individual levels. We focus on behaviour while drawing parallels with physiological and performance-related traits. First, we outline some of the confusion surrounding the terminology used to describe repeatable inter-individual differences in behaviour. Second, we argue that acknowledging individual behavioural differences can help researchers avoid sampling and experimental bias, increase explanatory power and, ultimately, understand how selection acts on physiological traits. Third, we summarize the latest methods to collect, analyse and present data on individual trait variation. We note that, while measuring the repeatability of phenotypic traits is informative in its own right, it is only the first step towards understanding how natural selection and genetic architecture shape intra-specific variation in complex, labile traits. Thus, understanding how and why behavioural traits evolve requires linking repeatable inter-individual behavioural differences with core aspects of physiology (e.g. neurophysiology, endocrinology, energy metabolism) and evolutionary biology (e.g. selection gradients, heritability). © 2016. Published by The Company of Biologists Ltd.

  13. Nutritional Status Driving Infection by Trypanosoma cruzi: Lessons from Experimental Animals

    Directory of Open Access Journals (Sweden)

    Guilherme Malafaia

    2011-01-01

    Full Text Available This paper reviews the scientific knowledge about protein-energy and micronutrient malnutrition in the context of Chagas disease, especially in experimental models. The search of articles was conducted using the electronic databases of SciELO (Scientific Electronic Library Online, PubMed and MEDLINE published between 1960 and March 2010. It was possible to verify that nutritional deficiencies (protein-energy malnutrition and micronutrient malnutrition exert a direct effect on the infection by T. cruzi. However, little is known about the immunological mechanisms involved in the relationship “nutritional deficiencies and infection by T. cruzi”. A hundred years after the discovery of Chagas disease many aspects of this illness still require clarification, including the effects of nutritional deficiencies on immune and pathological mechanisms of T. cruzi infection.

  14. Enhancing search efficiency by means of a search filter for finding all studies on animal experimentation in PubMed.

    Science.gov (United States)

    Hooijmans, Carlijn R; Tillema, Alice; Leenaars, Marlies; Ritskes-Hoitinga, Merel

    2010-07-01

    Collecting and analysing all available literature before starting an animal experiment is important and it is indispensable when writing a systematic review (SR) of animal research. Writing such review prevents unnecessary duplication of animal studies and thus unnecessary animal use (Reduction). One of the factors currently impeding the production of 'high-quality' SRs in laboratory animal science is the fact that searching for all available literature concerning animal experimentation is rather difficult. In order to diminish these difficulties, we developed a search filter for PubMed to detect all publications concerning animal studies. This filter was compared with the method most frequently used, the PubMed Limit: Animals, and validated further by performing two PubMed topic searches. Our filter performs much better than the PubMed limit: it retrieves, on average, 7% more records. Other important advantages of our filter are that it also finds the most recent records and that it is easy to use. All in all, by using our search filter in PubMed, all available literature concerning animal studies on a specific topic can easily be found and assessed, which will help in increasing the scientific quality and thereby the ethical validity of animal experiments.

  15. Experimental setting for assessing mechanical strength of gas hydrate pellet

    Energy Technology Data Exchange (ETDEWEB)

    Jeong, S.J.; Choi, J.H.; Koh, B.H. [Dongguk Univ., Phil-dong, Chung-gu, Seoul (Korea, Republic of). Dept. of Mechanical Engineering

    2008-07-01

    Due to the constant increase in global demand for clean energy, natural gas production from stranded medium and small size gas wells has drawn significant interest. Because the ocean transport of natural gas in the form of solid hydrate pellets (NGHP) has been estimated to be economically feasible, several efforts have been made to develop a total NGHP ocean transport chain. The investigation of mechanical strength of solid-form hydrate pellet has been an important task in fully exploiting the benefit of gas hydrate in the perspective of mass transportation and storage. This paper provided the results of a preliminary study regarding the assessment of mechanical properties of the gas hydrate pellet. The preliminary study suggested some of the key issues regarding formation and strength of gas hydrate pellets. Instead of utilizing the gas hydrate pellet, the study focused on a preliminary test setup for developing the ice pellet which was readily applied to the gas hydrate pellet in the future. The paper described the pelletization of ice powder as well as the experimental setup. Several photographs were illustrated, including samples of ice pellets; compression test for ice pellet using air press and load cell; and the initiation of crack in the cross section of an ice pellet. It was found that mechanical strength, especially, compression strength was not significantly affected by different level of press-forming force up to a certain level. 4 refs., 1 tab., 4 figs.

  16. Numerical and Experimental Study of Mechanisms Involved in Boiling Histotripsy.

    Science.gov (United States)

    Pahk, Ki Joo; Gélat, Pierre; Sinden, David; Dhar, Dipok Kumar; Saffari, Nader

    2017-12-01

    The aim of boiling histotripsy is to mechanically fractionate tissue as an alternative to thermal ablation for therapeutic applications. In general, the shape of a lesion produced by boiling histotripsy is tadpole like, consisting of a head and a tail. Although many studies have demonstrated the efficacy of boiling histotripsy for fractionating solid tumors, the exact mechanisms underpinning this phenomenon are not yet well understood, particularly the interaction of a boiling vapor bubble with incoming incident shockwaves. To investigate the mechanisms involved in boiling histotripsy, a high-speed camera with a passive cavitation detection system was used to observe the dynamics of bubbles produced in optically transparent tissue-mimicking gel phantoms exposed to the field of a 2.0-MHz high-intensity focused ultrasound (HIFU) transducer. We observed that boiling bubbles were generated in a localized heated region and cavitation clouds were subsequently induced ahead of the expanding bubble. This process was repeated with HIFU pulses and eventually resulted in a tadpole-shaped lesion. A simplified numerical model describing the scattering of the incident ultrasound wave by a vapor bubble was developed to help interpret the experimental observations. Together with the numerical results, these observations suggest that the overall size of a lesion induced by boiling histotripsy is dependent on the sizes of (i) the heated region at the HIFU focus and (ii) the backscattered acoustic field by the original vapor bubble. Copyright © 2017 World Federation for Ultrasound in Medicine and Biology. Published by Elsevier Inc. All rights reserved.

  17. Mechanisms of Osteoarthritic Pain. Studies in Humans and Experimental Models

    Directory of Open Access Journals (Sweden)

    Annett Eitner

    2017-11-01

    Full Text Available Pain due to osteoarthritis (OA is one of the most frequent causes of chronic pain. However, the mechanisms of OA pain are poorly understood. This review addresses the mechanisms which are thought to be involved in OA pain, derived from studies on pain mechanisms in humans and in experimental models of OA. Three areas will be considered, namely local processes in the joint associated with OA pain, neuronal mechanisms involved in OA pain, and general factors which influence OA pain. Except the cartilage all structures of the joints are innervated by nociceptors. Although the hallmark of OA is the degradation of the cartilage, OA joints show multiple structural alterations of cartilage, bone and synovial tissue. In particular synovitis and bone marrow lesions have been proposed to determine OA pain whereas the contribution of the other pathologies to pain generation has been studied less. Concerning the peripheral neuronal mechanisms of OA pain, peripheral nociceptive sensitization was shown, and neuropathic mechanisms may be involved at some stages. Structural changes of joint innervation such as local loss and/or sprouting of nerve fibers were shown. In addition, central sensitization, reduction of descending inhibition, descending excitation and cortical atrophies were observed in OA. The combination of different neuronal mechanisms may define the particular pain phenotype in an OA patient. Among mediators involved in OA pain, nerve growth factor (NGF is in the focus because antibodies against NGF significantly reduce OA pain. Several studies show that neutralization of interleukin-1β and TNF may reduce OA pain. Many patients with OA exhibit comorbidities such as obesity, low grade systemic inflammation and diabetes mellitus. These comorbidities can significantly influence the course of OA, and pain research just began to study the significance of such factors in pain generation. In addition, psychologic and socioeconomic factors may aggravate

  18. Anticonvulsant activity of the fractionated extract of Crinum jagus bulbs in experimental animals

    Directory of Open Access Journals (Sweden)

    Azikiwe CCA

    2012-05-01

    Full Text Available Objective: To investigate the anticonvulsant activity of the bulbs of Crinum jagus in experimental animals. Methods: The uprooted bulbs were air dried for a week and ground into creamy-paste. 200g of paste was macerated each in 2 litres of water, ethanol and petroleum ether and filtered after 48 h. The obtained filtrates were each evaporated at the appropriate temperature to solid residue. The residues were further fractionated with successive changes of petroleum ether, ethyl acetate and n-butanol into a pooled filtrate which was further evaporated to dry solid brown-paste. Phytochemistry was carried out based on Treas and Evans method of 1987. The acute toxicity study (LD50 was carried based on Lorke ’s 1983 method. Convulsion was induced using maximum electric shock (MEST, pentylenetetrazole(PTZ, strychnine and Picrotoxin in the appropriate animal models. Seizures onset time and death time were used as successful induction of convulsion while prolongations of these features were taken as anticonvulsant activity. Results where possible, were statistically analyzed using SPSS-16.0 version. Results: The LD 50 was got at 1118.003mg/kg (IP in mice using Lorke ’s 1983 method. Fractionated extract of Crinum jagus exhibited dose dependent antiseizure against MEST induced seizure (P<0.001 and comparable to that of phenytoin, a standard anti generalized tonic-clonic seizure. There were also observable antiseizure activity of the fractionated extracts against PTZ, strychnine and Picrotoxin induced seizure and comparable to their standard corresponding antiseizures. Conclusions: We conclude that the bulbs of Crinum jagus possess proven broad spectrum antiseizure and perhaps antiepileptogenic activity thus justifies its use in traditional medicine. Clinical trial in man is recommended.

  19. Communication and Collective Consensus Making in Animal Groups via Mechanical Interactions

    Science.gov (United States)

    Várkonyi, Péter L.

    2011-06-01

    Mechanical constraints have a strong influence on the dynamics and structure of granular aggregations. The contact forces within dense suspensions of active particles may give rise to intriguing phenomena, including anomalous density fluctuations, long-range orientational ordering, and spontaneous pattern formation. Various authors have proposed that these physical phenomena contribute to the ability of animal groups to move coherently. Our systematic numerical simulations confirm that spontaneous interactions of elongated individuals can trigger oriented motion in small groups. They are, however, insufficient in larger ones, despite their significant imprint on the group's internal structure. It is also demonstrated that preferred directions of motion of a minority of group members can be communicated to others solely by mechanical interactions. These findings strengthen the link between pattern formation in active nematics and the collective decision making of social animals.

  20. Exercise training on cardiovascular diseases: Role of animal models in the elucidation of the mechanisms

    Directory of Open Access Journals (Sweden)

    Bruno Rodrigues

    2017-05-01

    Full Text Available Abstract Cardiovascular diseases, which include hypertension, coronary artery disease/myocardial infarction and heart failure, are one of the major causes of disability and death worldwide. On the other hand, physical exercise acts in the preventionand treatment of these conditions. In fact, several experiments performed in human beings have demonstrated the efficiency of physical exercise to alter clinical signals observed in these diseases, such as high blood pressure and exercise intolerance. However, even if human studies demonstrated the clinical efficiency of physical exercise, most extensive mechanisms responsible for this phenomenon still have to be elucidated. In this sense, studies using animal models seem to be a good option to demonstrate such mechanisms. Therefore, the aims of the present study are describing the main pathophysiological characteristics of the animal models used in the study of cardiovascular diseases, as well as the main mechanismsassociated with the benefits of physical exercise.

  1. Mechanical properties and grindability of experimental Ti-Au alloys.

    Science.gov (United States)

    Takahashi, Masatoshi; Kikuchi, Masafumi; Okuno, Osamu

    2004-06-01

    Experimental Ti-Au alloys (5, 10, 20 and 40 mass% Au) were made. Mechanical properties and grindability of the castings of the Ti-Au alloys were examined. As the concentration of gold increased to 20%, the yield strength and the tensile strength of the Ti-Au alloys became higher without markedly deteriorating their ductility. This higher strength can be explained by the solid-solution strengthening of the a titanium. The Ti-40%Au alloy became brittle because the intermetallic compound Ti3Au precipitated intensively near the grain boundaries. There was no significant difference in the grinding rate and grinding ratio among all the Ti-Au alloys and the pure titanium at any speed.

  2. Mechanical design of the small-scale experimental ADS: MYRRHA

    Energy Technology Data Exchange (ETDEWEB)

    Maes, Dirk [SCKCEN, Reactor Physics and MYRRHA Department, Boeretang 200, B-2400 Mol (Belgium)

    2006-10-15

    Since 1998, SCK*CEN, in partnership with IBA s.a. and many European research laboratories, is designing a multipurpose Accelerator Driven System (ADS) - MYRRHA - and is conducting an associated R and D support programme. MYRRHA aims to serve as a basis for the European experimental ADS to provide protons and neutrons for various R and D applications. Besides an overall configuration of the MYRRHA reactor internals, the description in this paper is limited to the mechanical design of the main components of the Primary System and Associated Equipment (vessel and cover, diaphragm, spallation loop, sub-critical core, primary cooling system, emergency cooling system, in-vessel fuel storage and fuel transfer machine), the conceptual design of the robotics for In-Service Inspection and Repair (ISIR), together with the remote handling for operation and maintenance (O and M). (author)

  3. Experimental investigation of the mechanical properties of Alfas stone

    Directory of Open Access Journals (Sweden)

    Konstas N. Kaklis

    2017-04-01

    Full Text Available This paper focuses on the experimental investigation of the mechanical properties of the Alfas natural building stone. Two series of uniaxial compression tests and indirect tensile tests (Brazilian tests were performed in order to determine the uniaxial compressive strength and the indirect tensile strength respectively. Different sets of cylindrical specimens and circular discs were prepared by varying their geometry in order to examine the size effect on the respective strength values. Also, the size effect was investigated with respect to the calculated intact rock modulus and Poisson’s ratio. All specimens were prepared by following the ISRM suggested methods and the load was applied using a stiff 1600 kN MTS hydraulic testing machine and a 500 kN load cell. Strain was measured using biaxial 0/90 stacked rosettes appropriately attached on each specimen.

  4. Understanding organometallic reaction mechanisms and catalysis experimental and computational tools computational and experimental tools

    CERN Document Server

    Ananikov, Valentin P

    2014-01-01

    Exploring and highlighting the new horizons in the studies of reaction mechanisms that open joint application of experimental studies and theoretical calculations is the goal of this book. The latest insights and developments in the mechanistic studies of organometallic reactions and catalytic processes are presented and reviewed. The book adopts a unique approach, exemplifying how to use experiments, spectroscopy measurements, and computational methods to reveal reaction pathways and molecular structures of catalysts, rather than concentrating solely on one discipline. The result is a deeper

  5. Annular tautomerism: experimental observations and quantum mechanics calculations

    Science.gov (United States)

    Cruz-Cabeza, Aurora J.; Schreyer, Adrian; Pitt, William R.

    2010-06-01

    The use of MP2 level quantum mechanical (QM) calculations on isolated heteroaromatic ring systems for the prediction of the tautomeric propensities of whole molecules in a crystalline environment was examined. A Polarisable Continuum Model was used in the calculations to account for environment effects on the tautomeric relative stabilities. The calculated relative energies of tautomers were compared to relative abundances within the Cambridge Structural Database (CSD) and the Protein Data Bank (PDB). The work was focussed on 84 annular tautomeric forms of 34 common ring systems. Good agreement was found between the calculations and the experimental data even if the quantity of these data was limited in many cases. The QM results were compared to those produced by much faster semiempirical calculations. In a search for other sources of the useful experimental data, the relative numbers of known compounds in which prototropic positions were often substituted by heavy atoms were also analysed. A scheme which groups all annular tautomeric transformations into 10 classes was developed. The scheme was designed to encompass a comprehensive set of known and theoretically possible tautomeric ring systems generated as part of a previous study. General trends across analogous ring systems were detected as a result. The calculations and statistics collected on crystallographic data as well as the general trends observed should be useful for the better modelling of annular tautomerism in the applications such as computer-aided drug design, small molecule crystal structure prediction, the naming of compounds and the interpretation of protein—small molecule crystal structures.

  6. Comparison of the environmental performance of light mechanization and animal traction using a modular LCA approach

    DEFF Research Database (Denmark)

    Cerutti, Alessandro K.; Calvo, Angela; Bruun, Sander

    2014-01-01

    Animal traction has supported humans in most field operations since the origin of agriculture. With the introduction of mechanization, humans gained access to much more work power at similar management costs and were able to significantly increase the productivity and time efficiency of field...... Italy, while use of machine traction was evaluated using field data on two-wheel tractors performing the operations in similar production systems, converted to the specific functional unit. Owing to the differing properties of mechanical and living systems, it was difficult to establish a reliable...

  7. Review of reproductive and developmental toxicity induced by organotins in aquatic organisms and experimental animals

    Energy Technology Data Exchange (ETDEWEB)

    Hirose, A.; Takagi, A.; Nishimura, T.; Kanno, J.; Ema, M. [National Inst. of Health Sciences, Tokyo (Japan)

    2004-09-15

    Widespread use of organotins has caused increasing amounts to be released into the environment. The most important non-pesticidal route of entry of organotins into the environment is through leaching of organotin-stabilized PVC in water, and the use in antifouling agents, resulting in the introduction of organotin into the aquatic environment. Data are available regarding the detection of butyltins and phenyltins in aquatic marine organisms and marine products. Food chain bioamplification of butyltin in oysters, mud crabs, marine mussels, chinook salmons, dolphins, tunas, and sharks and of phenyltin in carps and horseshoe crabs has been reported. These findings indicate that organotins accumulate in the food chain and are bioconcentrated, and that humans can be exposed to organotins via seafood. The levels of organotin compounds in seafood are not considered to be sufficiently high to affect human health. However, Belfroid et al. (2000) noted that more research on residual TBT levels in seafood was needed before a definitive conclusion on possible health risks could be drawn. Although the toxicity of organotins has been extensively reviewed, the reproductive and developmental toxicity of organotins is not well understood. We summarized the data of the studies on reproductive and developmental toxicity of organotins in aquatic organisms and experimental animals.

  8. Comparison of Immunoprotection of Leptospira Recombinant Proteins with conventional vaccine in experimental animals.

    Science.gov (United States)

    Parthiban, M; Kumar, S Senthil; Balachandran, C; Kumanan, K; Aarthi, K S; Nireesha, G

    2015-12-01

    Leptospirosis is a bacterial disease caused by bacteria of the genus Leptospira affecting humans and animals. Untreated leptospirosis may result in severe kidney damage, meningitis, liver failure, respiratory distress, and even death. Virulent leptospirosis can rapidly enter kidney fibroblasts and induce a programmed cell death. Thus, it is a challenge for immunologists to develop an effective and safe leptospirosis vaccine. Here, we compared the commercial canine leptospira vaccine and recombinant proteins (OmpL1 and LipL41) with and without adjuvant in terms of immune response and challenge studies in hamsters and immune response studies alone in experimental dogs. The outer membrane proteins viz., lipL41 and OmpL1 of leptospira interrogans serovars icterohaemorrhagiae were amplified. The primers were designed in such a way that amplified products of OmpL1 and lipL41 were ligated and cloned simultaneously into a single vector. The cloned products were expressed in E. coli BL21 cells. The immunoprotection studies were conducted for both recombinant proteins and commercial vaccine. The challenge experiment studies revealed that combination of both rLip41 and rOmpL1 and commercial vaccine gave 83% and 87% protection, respectively. Histopathological investigation revealed mild sub lethal changes were noticed in liver and kidney in commercially vaccinated group alone. The immune responses against recombinant leptospiral proteins were also demonstrated in dogs.

  9. Experimental strategies for the identification and characterization of adhesive proteins in animals: a review

    Science.gov (United States)

    Hennebert, Elise; Maldonado, Barbara; Ladurner, Peter; Flammang, Patrick; Santos, Romana

    2015-01-01

    Adhesive secretions occur in both aquatic and terrestrial animals, in which they perform diverse functions. Biological adhesives can therefore be remarkably complex and involve a large range of components with different functions and interactions. However, being mainly protein based, biological adhesives can be characterized by classical molecular methods. This review compiles experimental strategies that were successfully used to identify, characterize and obtain the full-length sequence of adhesive proteins from nine biological models: echinoderms, barnacles, tubeworms, mussels, sticklebacks, slugs, velvet worms, spiders and ticks. A brief description and practical examples are given for a variety of tools used to study adhesive molecules at different levels from genes to secreted proteins. In most studies, proteins, extracted from secreted materials or from adhesive organs, are analysed for the presence of post-translational modifications and submitted to peptide sequencing. The peptide sequences are then used directly for a BLAST search in genomic or transcriptomic databases, or to design degenerate primers to perform RT-PCR, both allowing the recovery of the sequence of the cDNA coding for the investigated protein. These sequences can then be used for functional validation and recombinant production. In recent years, the dual proteomic and transcriptomic approach has emerged as the best way leading to the identification of novel adhesive proteins and retrieval of their complete sequences. PMID:25657842

  10. Selective segmental sclerotherapy of the liver by transportal absolute ethanol injection: an animal experimental study

    International Nuclear Information System (INIS)

    Pan Jie; Yang Ning; Zhang Zhongzhong; Hu Libin; Chen Jie; Wu Wei; Jin Zhengyu; Liu Wei

    2003-01-01

    Objective: To evaluate the safety and efficacy of selective segmental sclerotherapy (SSS) of the liver by transportal absolute ethanol injection with an animal experimental study, and to discuss several technical points involved in this method. Methods: Thirty dogs received SSS of the liver by transportal absolute ethanol injection with the injection dose of 0.2-1.0 ml/kg, repeated examinations of blood ethanol level, WBC, and liver functions were done, and CT and pathological examinations of the liver were performed. Results: All dogs treated with SSS survived during the study. The maximum elevation of blood ethanol values occurred in group F. Its average value was (1.603 ± 0.083) mg/ml, which was much lower than that of death level. Transient elevations of blood WBC and ALT were seen. The average values of WBC and ALT were (46.36 ± 7.28) x 10 9 and (827.36 ± 147.25) U/L, respectively. CT and pathological examinations proved that the dogs given SSS by transportal absolute ethanol injection with the injection dose of 0.3-1.0 ml/kg had a complete wedge-shaped necrosis in the liver. Conclusion: Selective segmental sclerotherapy of the liver by transportal ethanol injection was quite safe and effective if the proper dose of ethanol was injected. SSS may be useful in the treatment of HCC

  11. 'I think it will eventually be done away with': Attitudes among healthcare professionals towards the current system of animal experimentation.

    Science.gov (United States)

    Dignon, Andrée

    2016-08-01

    This article describes a study of attitudes to the current system of animal experimentation (for the production of health interventions) among 52 UK healthcare professionals. These healthcare professionals participated in three separate focus groups (of 18, 17 and 17 participants) and were invited to respond to the question 'what is your opinion about the current system of animal testing?' The study focused specifically on their views of the current system (rather than their views of animal testing in general). The healthcare professionals were critical of the current system, particularly with regard to regulation, secrecy, validity, unnecessary suffering and welfare. © The Author(s) 2014.

  12. Influence of haemodynamic disturbances caused by acceleration on distribution of 125J-albumin in eyes of experimental animals

    International Nuclear Information System (INIS)

    Kozuchowska, I.; Wojtkowiak, M.; Tajchert, J.

    1975-01-01

    Examination of radioactivity in eyes of experimental animals (50 guinea pigs) was performed in order to investigate the disturbances in the intraocular blood circulation under the influence of centripetal accelerations. After an intracordial injection of 125 J-albumin the animals were whirled, up to the moment of bradycardia pointing to a breakdown of compensatory reactions of the circulatory system. Particular groups of animals were frozen in fluid nitrogen in various time. Results showed an increase of permeability of the blood-aqueous barrier for ablumins. (author)

  13. Astragaloside IV for Experimental Focal Cerebral Ischemia: Preclinical Evidence and Possible Mechanisms

    Directory of Open Access Journals (Sweden)

    Hui-Lin Wang

    2017-01-01

    Full Text Available Astragaloside IV (AST-IV is a principal component of Radix Astragali seu Hedysari (Huangqi and exerts potential neuroprotection in experimental ischemic stroke. Here, we systematically assessed the effectiveness and possible mechanisms of AST-IV for experimental acute ischemic stroke. An electronic search in eight databases was conducted from inception to March 2016. The study quality score was evaluated using the CAMARADES. Rev Man 5.0 software was used for data analyses. Thirteen studies with 244 animals were identified. The study quality score of included studies ranged from 3/10 to 8/10. Eleven studies showed significant effects of AST-IV for ameliorating the neurological function score (P<0.05; seven studies for reducing the infarct volume (P<0.05; and three or two studies for reducing the brain water content and Evans blue leakage (P<0.05, respectively, compared with the control. The mechanisms of AST-IV for ischemic stroke are multiple such as antioxidative/nitration stress reaction, anti-inflammatory, and antiapoptosis. In conclusion, the findings of present study indicated that AST-IV could improve neurological deficits and infarct volume and reduce the blood-brain barrier permeability in experimental cerebral ischemia despite some methodological flaws. Thus, AST-IV exerted a possible neuroprotective effect during the cerebral ischemia/reperfusion injury largely through its antioxidant, anti-inflammatory, and antiapoptosis properties.

  14. Experimental study on L-[1-13C] phenylalanine breath test for quantitative assessment of liver function with animal

    International Nuclear Information System (INIS)

    Yan Weili; Fudan Univ., Shanghai; Lin Xiangtong; Sun Dayu; Jiang Yibin; Sun Xu; Rong Lan; Liang Qi

    2006-01-01

    Objective: Using a small animal breath test model we designed and L-[1- 13 C] phenylalanine breath test ( 13 C-PheBT) of rats, the authors investigated its feasibility and validity and determined effective parameter of the test. Methods: Twenty male Sprague-Dawley (SD) weighting 280-290 g rats randomized into two groups acute hepatitis rats (n=10) and control rats (n=10). Hepatitis was induced by carbon tetrachloride (CCl 4 ) olive oil administration through intragastric gavage. PheBT was assisted by small mechanical ventilator improved and air samples were collected discontinuously, 20 mg/kg body weight L-[1- 13 C] phenylalanine ( 13 C-Phe) was administered intravenously. Twenty-nine breath samples were taken before and different intervals within sixty minutes after administration. 13 Cenrichment was measured by isotope ratio mass spectrometer. Results: All time phase curves of 13 C enrichment in rat breath reached a peak almost at 2 min after the intravenous administration of 13 C-Phe. The PheBT parameters, 13 C excretion rate constant (PheBT-K), of CCl 4 hepatitis rats were significantly lower than that of normal control rats [(2.45 ± 0.25) x 10 -2 min -1 vs (2.98 ± 0.19) x 10 -2 min -1 , t = 5.40, P 13 C fast phase disposition constant did not statistically differ between the two groups (t=0.58, P>0.05). PheBT-K had significant negative cor-relation with serum ALT, AKP, TBA and total bilirum TBIL (the correlation coefficient r is -0.74, -0.73, -0.82 and -0.67 respectively, P 0.05). Conclusions: It was indicated that the small animal breath test model we designed was a virtual tool to use in experimental study on breath test and PheBT-K was a sensitive index. (authors)

  15. Mechanical forces as information: an integrated approach to plant and animal development

    Directory of Open Access Journals (Sweden)

    Valeria eHernández-Hernández

    2014-06-01

    Full Text Available Mechanical forces such as tension and compression act throughout growth and development of multicellular organisms. These forces not only affect the size and shape of the cells and tissues but are capable of modifying the expression of genes and the localization of molecular components within the cell, in the plasma membrane, and in the plant cell wall. The magnitude and direction of these physical forces change with cellular and tissue properties such as elasticity. Thus, mechanical forces and the mesoscopic fields that emerge from their local action constitute important sources of positional information. Moreover, physical and biochemical processes interact in non-linear ways during tissue and organ growth in plants and animals. In this review we discuss how such mechanical forces are generated, transmitted, and sensed in these two lineages of multicellular organisms to yield long-range positional information. In order to do so we first outline a potentially common basis for studying patterning and mechanosensing that relies on the structural principle of tensegrity, and discuss how tensegral structures might arise in plants and animals. We then provide some examples of morphogenesis in which mechanical forces appear to act as positional information during development, offering a possible explanation for ubiquitous processes, such as the formation of periodic structures. Such examples, we argue, can be interpreted in terms of tensegral phenomena. Finally, we discuss the hypothesis of mechanically isotropic points as a potentially generic mechanism for the localization and maintenance of stem-cell niches in multicellular organisms. This comparative approach aims to help uncovering generic mechanisms of morphogenesis and thus reach a better understanding of the evolution and development of multicellular phenotypes, focusing on the role of physical forces in these processes.

  16. Synthetic torpor: A method for safely and practically transporting experimental animals aboard spaceflight missions to deep space

    Science.gov (United States)

    Griko, Yuri; Regan, Matthew D.

    2018-02-01

    Animal research aboard the Space Shuttle and International Space Station has provided vital information on the physiological, cellular, and molecular effects of spaceflight. The relevance of this information to human spaceflight is enhanced when it is coupled with information gleaned from human-based research. As NASA and other space agencies initiate plans for human exploration missions beyond low Earth orbit (LEO), incorporating animal research into these missions is vitally important to understanding the biological impacts of deep space. However, new technologies will be required to integrate experimental animals into spacecraft design and transport them beyond LEO in a safe and practical way. In this communication, we propose the use of metabolic control technologies to reversibly depress the metabolic rates of experimental animals while in transit aboard the spacecraft. Compared to holding experimental animals in active metabolic states, the advantages of artificially inducing regulated, depressed metabolic states (called synthetic torpor) include significantly reduced mass, volume, and power requirements within the spacecraft owing to reduced life support requirements, and mitigated radiation- and microgravity-induced negative health effects on the animals owing to intrinsic physiological properties of torpor. In addition to directly benefitting animal research, synthetic torpor-inducing systems will also serve as test beds for systems that may eventually hold human crewmembers in similar metabolic states on long-duration missions. The technologies for inducing synthetic torpor, which we discuss, are at relatively early stages of development, but there is ample evidence to show that this is a viable idea and one with very real benefits to spaceflight programs. The increasingly ambitious goals of world's many spaceflight programs will be most quickly and safely achieved with the help of animal research systems transported beyond LEO; synthetic torpor may

  17. Considerations for Experimental Animal Models of Concussion, Traumatic Brain Injury, and Chronic Traumatic Encephalopathy—These Matters Matter

    Directory of Open Access Journals (Sweden)

    Mark W. Wojnarowicz

    2017-06-01

    Full Text Available Animal models of concussion, traumatic brain injury (TBI, and chronic traumatic encephalopathy (CTE are widely available and routinely deployed in laboratories around the world. Effective animal modeling requires careful consideration of four basic principles. First, animal model use must be guided by clarity of definitions regarding the human disease or condition being modeled. Concussion, TBI, and CTE represent distinct clinical entities that require clear differentiation: concussion is a neurological syndrome, TBI is a neurological event, and CTE is a neurological disease. While these conditions are all associated with head injury, the pathophysiology, clinical course, and medical management of each are distinct. Investigators who use animal models of these conditions must take into account these clinical distinctions to avoid misinterpretation of results and category mistakes. Second, model selection must be grounded by clarity of purpose with respect to experimental questions and frame of reference of the investigation. Distinguishing injury context (“inputs” from injury consequences (“outputs” may be helpful during animal model selection, experimental design and execution, and interpretation of results. Vigilance is required to rout out, or rigorously control for, model artifacts with potential to interfere with primary endpoints. The widespread use of anesthetics in many animal models illustrates the many ways that model artifacts can confound preclinical results. Third, concordance between key features of the animal model and the human disease or condition being modeled is required to confirm model biofidelity. Fourth, experimental results observed in animals must be confirmed in human subjects for model validation. Adherence to these principles serves as a bulwark against flawed interpretation of results, study replication failure, and confusion in the field. Implementing these principles will advance basic science discovery and

  18. Survey of basic medical researchers on the awareness of animal experimental designs and reporting standards in China.

    Directory of Open Access Journals (Sweden)

    Bin Ma

    Full Text Available To investigate the awareness and use of the Systematic Review Center for Laboratory Animal Experimentation's (SYRCLE risk-of-bias tool, the Animal Research: Reporting of In Vivo Experiments (ARRIVE reporting guidelines, and Gold Standard Publication Checklist (GSPC in China in basic medical researchers of animal experimental studies.A national questionnaire-based survey targeting basic medical researchers was carried in China to investigate the basic information and awareness of SYRCLE's risk of bias tool, ARRIVE guidelines, GSPC, and animal experimental bias risk control factors. The EpiData3.1 software was used for data entry, and Microsoft Excel 2013 was used for statistical analysis in this study. The number of cases (n and percentage (% of classified information were statistically described, and the comparison between groups (i.e., current students vs. research staff was performed using chi-square test.A total of 298 questionnaires were distributed, and 272 responses were received, which included 266 valid questionnaires (from 118 current students and 148 research staff. Among the 266 survey participants, only 15.8% was aware of the SYRCLE's risk of bias tool, with significant difference between the two groups (P = 0.003, and the awareness rates of ARRIVE guidelines and GSPC were only 9.4% and 9.0%, respectively; 58.6% survey participants believed that the reports of animal experimental studies in Chinese literature were inadequate, with significant difference between the two groups (P = 0.004. In addition, only approximately 1/3 of the survey participants had read systematic reviews and meta-analysis reports of animal experimental studies; only 16/266 (6.0% had carried out/participated in and 11/266 (4.1% had published systematic reviews/meta-analysis of animal experimental studies.The awareness and use rates of SYRCLE's risk-of-bias tool, the ARRIVE guidelines, and the GSPC were low among Chinese basic medical researchers. Therefore

  19. Experimental animal studies on effects of hyperthermia on the central nervous system: an overview

    Energy Technology Data Exchange (ETDEWEB)

    Haveman, J; Hulshof, M C.C.M. [Department of Radiotherapy, Academisch Medisch Centrum, Amsterdam (Netherlands); Sminia, P [Department of Radiation Oncology, Section Radiobiology, VU Medical Center, Amsterdam (Netherlands); Wondergem, J [Department of Occupational Health and Risk Assessment, Leids Universitair Medisch Centrum, Leiden (Netherlands); Zee van der, J [Department of Radiation Oncology, Hyperthermia Unit, Erasmus MC - Daniel den Hoed Cancer Center, Rotterdam (Netherlands)

    2005-07-01

    Full text: From the experimental studies reported in the literature it may be concluded that the maximum tolerable heat dose in CNS is 42{sup o}C to 42.5{sup o}C for 40 to 60 min or 43{sup o}C for 10 to 30 min. This in spite of diversity in animal species studied, as well as the different endpoints for assessment of effects, the different parts of CNS treated, differences in procedures used for anesthesia, thermometry and heating techniques applied. The effects of hyperthermia are expressed immediately or within a few days after treatment and heat injury to neural tissue apparently results in neurological abnormalities which, unless lethal, are transient in most cases. Histological studies show irreversible lesions after high heat dose, characterized by coagulation necrosis. Thermal injury to normal neural tissue is repaired by fibrotic or gliotic scarring. Surviving neuronal elements my be responsible for functional recovery from heat injury, which is, however, dependent on the injured volume and anatomical site of the lesion. Hence, the data indicate a correlation between the exposed volume and toxicity of the heat treatment. The relatively high heat dose tolerated in interstitial heating can be ascribed to this volume effect, since the heated volume of normal neural tissue generally was small and not responsible for vital functions. Late effects, many months after treatment have not been reported. The spinal cord data on maximum tolerable heat dose, point in the same direction as the data on the brain. All studies show that, as with brain, the spinal cord is sensitive to heat. The maximum tolerated heat dose of the cervical part after local hyperthermia lies in the range of 40-60 min at 42-42.5{sup o}C, or less than 30 min at 43{sup o}C. No late effects were reported. The observations on neurology and heat sensitivity of the spinal cord in mice are very similar to those of the rat. There is good evidence indicating that white matter is more heat resistant than

  20. Experimental animal studies on effects of hyperthermia on the central nervous system: an overview

    International Nuclear Information System (INIS)

    Haveman, J.; Hulshof, M.C.C.M.; Sminia, P.; Wondergem, J.; Zee van der, J.

    2005-01-01

    Full text: From the experimental studies reported in the literature it may be concluded that the maximum tolerable heat dose in CNS is 42 o C to 42.5 o C for 40 to 60 min or 43 o C for 10 to 30 min. This in spite of diversity in animal species studied, as well as the different endpoints for assessment of effects, the different parts of CNS treated, differences in procedures used for anesthesia, thermometry and heating techniques applied. The effects of hyperthermia are expressed immediately or within a few days after treatment and heat injury to neural tissue apparently results in neurological abnormalities which, unless lethal, are transient in most cases. Histological studies show irreversible lesions after high heat dose, characterized by coagulation necrosis. Thermal injury to normal neural tissue is repaired by fibrotic or gliotic scarring. Surviving neuronal elements my be responsible for functional recovery from heat injury, which is, however, dependent on the injured volume and anatomical site of the lesion. Hence, the data indicate a correlation between the exposed volume and toxicity of the heat treatment. The relatively high heat dose tolerated in interstitial heating can be ascribed to this volume effect, since the heated volume of normal neural tissue generally was small and not responsible for vital functions. Late effects, many months after treatment have not been reported. The spinal cord data on maximum tolerable heat dose, point in the same direction as the data on the brain. All studies show that, as with brain, the spinal cord is sensitive to heat. The maximum tolerated heat dose of the cervical part after local hyperthermia lies in the range of 40-60 min at 42-42.5 o C, or less than 30 min at 43 o C. No late effects were reported. The observations on neurology and heat sensitivity of the spinal cord in mice are very similar to those of the rat. There is good evidence indicating that white matter is more heat resistant than grey matter as data

  1. Experimental investigations of nonlinearities and destruction mechanisms of an experimental phospholipid-based ultrasound contrast agent.

    Science.gov (United States)

    Casciaro, Sergio; Palmizio Errico, Rosa; Errico, Rosa Palmizio; Conversano, Francesco; Demitri, Christian; Distante, Alessandro

    2007-02-01

    We sought to characterize the acoustical behavior of the experimental ultrasound contrast agent BR14 by determining the acoustic pressure threshold above which nonlinear oscillation becomes significant and investigating microbubble destruction mechanisms. We used a custom-designed in vitro setup to conduct broadband attenuation measurements at 3.5 MHz varying acoustic pressure (range, 50-190 kPa). We also performed granulometric analyses on contrast agent solutions to accurately measure microbubble size distribution and to evaluate insonification effects. Attenuation did not depend on acoustic pressure less than 100 kPa, indicating this pressure as the threshold for the appearance of microbubble nonlinear behavior. At the lowest excitation amplitude, attenuation increased during insonification, while, at higher excitation levels, the attenuation decreased over time, indicating microbubble destruction. The destruction rate changed with pressure amplitude suggesting different destruction mechanisms, as it was confirmed by granulometric analysis. Microbubbles showed a linear behavior until 100 kPa, whereas beyond this value significant nonlinearities occurred. Observed destruction phenomena seem to be mainly due to gas diffusion and bubble fragmentation mechanisms.

  2. Novel Experimental Techniques to Investigate Wellbore Damage Mechanisms

    Science.gov (United States)

    Choens, R. C., II; Ingraham, M. D.; Lee, M.; Dewers, T. A.

    2017-12-01

    A new experimental technique with unique geometry is presented investigating deformation of simulated boreholes using standard axisymmetric triaxial deformation equipment. The Sandia WEllbore SImulation, SWESI, geometry, uses right cylinders of rock 50mm in diameter and 75mm in length. A 11.3mm hole is drilled perpendicular to the axis of the cylinder in the center of the sample to simulate a borehole. The hole is covered with a solid metal cover, and sealed with polyurethane. The metal cover can be machined with a high-pressure port to introduce different fluid chemistries into the borehole at controlled pressures. Samples are deformed in a standard load frame under confinement, allowing for a broad range of possible stresses, load paths, and temperatures. Experiments in this study are loaded to the desired confining pressure, then deformed at a constant axial strain rate or 10-5 sec-1. Two different suites of experiments are conducted in this study on sedimentary and crystalline rock types. The first series of experiments are conducted on Mancos Shale, a finely laminated transversely isotropic rock. Samples are cored at three different orientations to the laminations. A second series of experiments is conducted on Sierra White granite with different fluid chemistries inside the borehole. Numerical modelling and experimental observations including CT-microtomography demonstrate that stresses are concentrated around the simulated wellbore and recreate wellbore deformation mechanisms. Borehole strength and damage development is dependent on anisotropy orientation and fluid chemistry. Observed failure geometries, particularly for Mancos shale, can be highly asymmetric. These results demonstrate uncertainties in in situ stresses measurements using commonly-applied borehole breakout techniques in complicated borehole physico-chemical environments. Sandia National Laboratories is a multimission laboratory managed and operated by National Technology and Engineering

  3. Molecular Mechanisms of Curcumin Renoprotection in Experimental Acute Renal Injury

    Directory of Open Access Journals (Sweden)

    Youling Fan

    2017-12-01

    Full Text Available As a highly perfused organ, the kidney is especially sensitive to ischemia and reperfusion. Ischemia-reperfusion (IR-induced acute kidney injury (AKI has a high incidence during the perioperative period in the clinic and is an important link in ischemic acute renal failure (IARF. Therefore, IR-induced AKI has important clinical significance and it is necessary to explore to develop drugs to prevent and alleviate IR-induced AKI. Curcumin [diferuloylmethane, 1,7-bis(4-hydroxy-3-methoxiphenyl-1,6-heptadiene-3,5-dione] is a polyphenol compound derived from Curcuma longa (turmeric and was shown to have a renoprotective effect on ischemia-reperfusion injury (IRI in a previous study. However, the specific mechanisms underlying the protective role of curcumin in IR-induced AKI are not completely understood. APPL1 is a protein coding gene that has been shown to be involved in the crosstalk between the adiponectin-signaling and insulin-signaling pathways. In the study, to investigate the molecular mechanisms of curcumin effects in kidney ischemia/reperfusion model, we observed the effect of curcumin in experimental models of IR-induced AKI and we found that curcumin treatment significantly increased the expression of APPL1 and inhibited the activation of Akt after IR treatment in the kidney. Our in vitro results showed that apoptosis of renal tubular epithelial cells was exacerbated with hypoxia-reoxygenation (HR treatment compared to sham control cells. Curcumin significantly decreased the rate of apoptosis in renal tubular epithelial cells with HR treatment. Moreover, knockdown of APPL1 activated Akt and subsequently aggravated apoptosis in HR-treated renal tubular epithelial cells. Conversely, inhibition of Akt directly reversed the effects of APPL1 knockdown. In summary, our study demonstrated that curcumin mediated upregulation of APPL1 protects against ischemia reperfusion induced AKI by inhibiting Akt phosphorylation.

  4. Anticonvulsant action of gamma-irradiated diazepam with correlation to certain brain amino acids and electrocorticogram activity in experimental animals

    International Nuclear Information System (INIS)

    Saad, S.F.; Roushdy, H.M.; Hassan, S.H.M.; Elkashef, H.S.; Mahdy, A.M.; Elsayeh, B.M.

    1994-01-01

    The effect of sterilization by gamma irradiation (215 KGy) of diazepam on is anticonvulsant action, on norma and depleted cerebral gamma aminobutyric acid (GABA), on glutamic acid, as well as electrocorticogram activity (ECOG) was determined in the experimental animals. For the evaluation of the anticonvulsant action of either diazepam (D) or irradiated diazepam (ID), pentyl ene tetrazole seizure test, was used and the protective dose 50 (PD50) was determined in adult male mice. GABA, the main central inhibitory transmitter which is implicated in the mechanism of the anticonvulsant action of D and its precursor glutamic acid, were electrophoretically separated and spectrophotometrical evaluated. Moreover, brain electrical activity was recorded using an electroencephalograph apparatus. Although the PD50 of ID as well the effect on normal brain cerebral GABA and glutamic acids did not differ significantly from that of D, yet there was certain variabilities. Thus, the effect of D was about 4 times more potent than the ID on elevating depleted cerebral GABA. Also, electrocorticogram records demonstrated that D produced a slight inhibition while ID induced a decrease in B rhythm with remarkable in the amplitude of ECOG waves. The same pattern of effects were obtained when D or ID were used in combination with INH (250 mg kg-1). 1 tab. 1 fig

  5. Vitamin D for the Treatment of Epilepsy: Basic Mechanisms, Animal Models and Clinical Trials

    Directory of Open Access Journals (Sweden)

    Kevin Pendo

    2016-12-01

    Full Text Available There is increasing evidence supporting dietary and alternative therapies for epilepsy, including the ketogenic diet, modified Atkins diet, and omega-3 fatty acids. Vitamin D is actively under investigation as a potential intervention for epilepsy. Vitamin D is fat soluble steroid which shows promise in animal models of epilepsy. Basic research has shed light on the possible mechanisms by which Vitamin D may reduce seizures, and animal data support the efficacy of Vitamin D in rat and mouse models of epilepsy. Very little clinical data exists to support the treatment of human epilepsy with Vitamin D, but positive findings from preliminary clinical trials warrant larger Phase I and II clinical trials in order to more rigorously determine the potential therapeutic value of Vitamin D as a treatment for human epilepsy.

  6. Adaptive Response in Animals Exposed to Non-Ionizing Radiofrequency Fields: Some Underlying Mechanisms

    Directory of Open Access Journals (Sweden)

    Yi Cao

    2014-04-01

    Full Text Available During the last few years, our research group has been investigating the phenomenon of adaptive response in animals exposed to non-ionizing radiofrequency fields. The results from several separate studies indicated a significant increase in survival, decreases in genetic damage as well as oxidative damage and, alterations in several cellular processes in mice pre-exposed to radiofrequency fields and subsequently subjected to sub-lethal or lethal doses of γ-radiation or injected with bleomycin, a radiomimetic chemical mutagen. These observations indicated the induction of adaptive response providing the animals the ability to resist subsequent damage. Similar studies conducted by independent researchers in mice and rats have supported our observation on increased survival. In this paper, we have presented a brief review of all of our own and other independent investigations on radiofrequency fields-induced adaptive response and some underlying mechanisms discussed.

  7. Hypogonadotropic hypogonadism and metabolic syndrome: insights from the high-fat diet experimental rabbit animal model.

    Science.gov (United States)

    Morelli, Annamaria; Vignozzi, Linda; Maggi, Mario

    2016-06-01

    The etiology of metabolic syndrome (MetS) is complex and involves the interplay between environmental, lifestyle and genetic determinants. MetS in men can be associated with a biochemical pattern of partial hypogonadotropic hypogonadism (HH). A similar pattern has been noted in both men and women with a variety of acute illnesses and chronic diseases, and there is ongoing debate regarding whether this phenomenon might adaptive (e.g. diverting resources from reproduction into survival), or maladaptive (e.g. anemia, sarcopenia, osteopenia and fatigue of androgen-deficiency amplify and widen the adverse consequences of the original disease-trigger). In women with hypothalamic amenorrhea (HA-HH secondary to chronic bioenergetic deficit from dietary restriction and/or intensive exercise), a genetic link to congenital HH (CHH) was recently established; women carrying monoallelic CHH gene mutations will typically not develop CHH, but are significantly more susceptible to HA. However, the male reproductive axis seems to be more resistant to similar environmental insults. In contrast, MetS-associated HH (mHH) is specifically a male phenomenon; the reproductive phenotype of females with MetS tending instead towards hyperandrogenism, rather than hypogonadism. The underlying pathogenic mechanisms responsible for mHH have not been clearly identified and, as yet, there has been no investigation of a potential role for CHH mutation carriage in its etiology. Over the decades, the use of either genetic- or diet-induced obesity and/or MetS animal models has greatly helped to illuminate the complex etiology of metabolic dysregulation, but the strong relationship between obesity/MetS and mHH in males has been largely neglected, with little or no information about the regulation of reproductive function by metabolic factors under conditions of bioenergetic excess. However, the pathogenic link between MetS and HH in males has been recently investigated in an animal model of high fat

  8. Study of {sup 99m}Tc-DMSA biodistribution in experimental animals

    Energy Technology Data Exchange (ETDEWEB)

    Castro, Thais O.M. de; Silva, Natanael G. da; Colturato, Maria T.; Felgueiras, Carlos F.; Mengatti, Jair; Fukumori, Neuza T.O.; Matsuda, Margareth M.N.; Araújo, Elaine B. de, E-mail: thais.castrom@gmail.com [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil). Centro de Radiofarmacia

    2017-11-01

    {sup 99m}Tc-DMSA, succimer ({sup 99m}Tc), is a radiopharmaceutical commonly used in nuclear medicine for renal function evaluation by imaging. In order to achieve adequate labeling of the product with good radiochemical yield and standardized biological distribution, the interval of 185 - 3700 MBq should be kept in a maximum volume of 3 mL for product labeling. Moreover, one should avoid exposing the reconstituted solution to oxygen and using the product after four hours post labeling. The aim of the study was to quantify and evaluate the influence of different DMSA complexes on biological distribution of the radiopharmaceutical in experimental animals, taking in account variations in the labeling parameters. Radiochemical purity was determined by paper and thin layer chromatography using both acetone/Whatman 3MM, 0.9% NaCl/TLC-SG and n-propanol/ H{sub 2}O/acetic acid (4:3:1 V/V/V)/TLC-SG systems respectively for quantification of {sup 99m}TcO{sub 4} - and {sup 99m}TcO{sub 2} plus some {sup 99m}Tc-DMSA complexes. The labeling activity did not significantly affect the extent of the main complex generation. The presence of oxygen and the concentration of {sup 99}Tc did not markedly change the percentage of the radiochemical impurities in the preparation. Radiochemical purity tests of the DMSA-{sup 99m}Tc based on IPEN-CNEN DMSA-TEC reagent and on another producer's reagent showed similar results. Although the routine method used by IPEN-CNEN to determine the radiochemical yield of {sup 99m}Tc-DMSA was not able to discriminate among {sup 99m}Tc-DMSA complexes, the renal uptake and the kidney to liver plus spleen uptake ratio in rats met the official compendia criteria for the radiopharmaceutical. (author)

  9. Effect of insertion torque on titanium implant osseointegration: an animal experimental study.

    Science.gov (United States)

    Duyck, Joke; Roesems, Rutger; Cardoso, Marcio V; Ogawa, Toru; De Villa Camargos, Germana; Vandamme, Katleen

    2015-02-01

    To evaluate the effect of implant insertion torque on the peri-implant bone healing and implant osseointegration. Bilaterally in the tibia of five adult New Zealand white rabbits, 20 implants were installed, subdivided into four groups, corresponding to two insertion torque conditions (low, 50 Ncm) and 2 experimental periods (2 weeks vs. 4 weeks of healing). The implant insertion torque was determined by the surgical drill diameter relative to the implant diameter. Implant osseointegration was evaluated by quantitative histology (bone-to-implant contact with host bone [BIC-host], with neoformed bone [BIC-de novo], with both bone types [BIC-total], and peri-implant bone [BA/TA]). Every response was modelled over time using GEE (general estimation equation) with an unstructured variance-covariance matrix to correct for dependency between the measurements from one animal. The statistical significance level of α = 0.05 was applied. Significantly, more BIC-host and BIC-total were recorded for H implants compared with L implants after 2 week of healing (P = 0.010 and P = 0.0001, respectively). However, this result was no longer found for the extended healing period. Furthermore, BIC-total significantly increased over time for L implants (P torque led to an increased BA/TA after 4 week of healing (P torque implants installed in the rabbit tibial bone osseointegrate with considerable de novo bone formation. This bone neoformation enables L implants to catch up, already during the early osseointegration stage, the initial inferior amount BIC contact compared with that of H implants. A negative impact of the created strain environment accompanying H insertion torque implant installation on the biological process of osseointegration could not be observed, at least not at tissue level. © 2013 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  10. Study of "9"9"mTc-DMSA biodistribution in experimental animals

    International Nuclear Information System (INIS)

    Castro, Thais O.M. de; Silva, Natanael G. da; Colturato, Maria T.; Felgueiras, Carlos F.; Mengatti, Jair; Fukumori, Neuza T.O.; Matsuda, Margareth M.N.; Araújo, Elaine B. de

    2017-01-01

    "9"9"mTc-DMSA, succimer ("9"9"mTc), is a radiopharmaceutical commonly used in nuclear medicine for renal function evaluation by imaging. In order to achieve adequate labeling of the product with good radiochemical yield and standardized biological distribution, the interval of 185 - 3700 MBq should be kept in a maximum volume of 3 mL for product labeling. Moreover, one should avoid exposing the reconstituted solution to oxygen and using the product after four hours post labeling. The aim of the study was to quantify and evaluate the influence of different DMSA complexes on biological distribution of the radiopharmaceutical in experimental animals, taking in account variations in the labeling parameters. Radiochemical purity was determined by paper and thin layer chromatography using both acetone/Whatman 3MM, 0.9% NaCl/TLC-SG and n-propanol/ H_2O/acetic acid (4:3:1 V/V/V)/TLC-SG systems respectively for quantification of "9"9"mTcO_4 - and "9"9"mTcO_2 plus some "9"9"mTc-DMSA complexes. The labeling activity did not significantly affect the extent of the main complex generation. The presence of oxygen and the concentration of "9"9Tc did not markedly change the percentage of the radiochemical impurities in the preparation. Radiochemical purity tests of the DMSA-"9"9"mTc based on IPEN-CNEN DMSA-TEC reagent and on another producer's reagent showed similar results. Although the routine method used by IPEN-CNEN to determine the radiochemical yield of "9"9"mTc-DMSA was not able to discriminate among "9"9"mTc-DMSA complexes, the renal uptake and the kidney to liver plus spleen uptake ratio in rats met the official compendia criteria for the radiopharmaceutical. (author)

  11. Tetrathyridia of Mesocestoides lineatus in Chinese Snakes and Their Adults Recovered from Experimental Animals

    Science.gov (United States)

    Cho, Shin-Hyeong; Kim, Tong-Soo; Kong, Yoon; Na, Byoung-Kuk

    2013-01-01

    Morphological characteristics of Mesocestoides lineatus tetrathyridia collected from Chinese snakes and their adults recovered from experimental animals were studied. The tetrathyridia were detected mainly in the mesentery of 2 snake species, Agkistrodon saxatilis (25%) and Elaphe schrenckii (20%). They were 1.73 by 1.02 mm in average size and had an invaginated scolex with 4 suckers. Adult tapeworms were recovered from 2 hamsters and 1 dog, which were orally infected with 5-10 larvae each. Adults from hamsters were about 32 cm long and those from a dog were about 58 cm long. The scolex was 0.56 mm in average width with 4 suckers of 0.17 by 0.15 mm in average size. Mature proglottids measured 0.29 by 0.91 mm (av.). Ovaries and vitellaria bilobed and located in the posterior portion of proglottids. The cirrus sac was oval-shaped and located median. Testes were follicular, distributed in both lateral fields of proglottids, and 41-52 in number per proglottid. Gravid proglottids were 1.84 by 1.39 mm (av.) with a characteristic paruterine organ. Eggs were 35 by 27 µm in average size with a hexacanth embryo. These morphological characteristics of adult worms were identical with those of M. lineatus reported previously. Therefore, it has been confirmed that the tetrathyridia detected in 2 species of Chinese snakes are the metacestodes of M. lineatus, and 2 snake species, A. saxatilis and E. schrenckii, play the role of intermediate hosts. PMID:24327778

  12. Monitoringsprogramma experimentele gecombineerde luchtwassers op veehouderijbedrijven = Measurement program on experimental multi-pollutant air scrubbers at animal houses

    NARCIS (Netherlands)

    Melse, R.W.; Hol, J.M.G.; Mosquera Losada, J.; Nijeboer, G.M.; Huis in 'T Veld, J.W.H.; Hattum, van T.G.; Kwikkel, R.K.; Dousma, F.; Ogink, N.W.M.

    2011-01-01

    A measurement program was carried out in which the performance of 5 experimental scrubbers on animal farms was monitored for the removal of ammonia, odour and fine dust (PM10, PM2.5). This reports discusses and evaluates the realization of the program and its results.

  13. Perceptions of Animal Experimentation: A Longitudinal Survey with Veterinary Students in Araçatuba, São Paulo, Brazil

    Science.gov (United States)

    Machado, Gisele F.; Melo, Guilherme D.; Perri, Silvia H. V.; Fernandes, Fernando V.; Moraes, Olívia C.; Souza, Milena S.; Grano, Fernanda G.; Silva, José E. S.; Nunes, Cáris M.

    2017-01-01

    Animal experimentation is a controversial topic, especially among the general public and the scientific community. Thirty-eight undergraduate students attending the College of Veterinary Medicine--São Paulo State University in the municipality of Araçatuba, São Paulo, Brazil, were followed up between 2008 and 2011 and were asked to complete an…

  14. Design and Experimental Investigation of Pneumatic Movement Mechanism Supported by Mechanic Cam and Crank Shaft

    Directory of Open Access Journals (Sweden)

    Salih KORUCU

    2015-02-01

    Full Text Available The pressurized air is applied to many sectors required purity and velocity. One of these sectors is to use of air as impulsive force in the moving mechanisms. In this study, the movement mechanism prototype worked with compressed air was designed and produced forlight vehicle engine as motorbike and ATV (All-Terrain Vehicle. In developed mechanisms, pneumatic artificial muscles were used for a given movement of crankshaft. A cam system was also designed for synchronization pneumatic muscles. In this way, these muscles transmit the synchronous movement to crankshaft. At the end of the study, the developed mechanism was mounted on an ATV vehicle(110 cc/ Cubic Centimeter, engine displacement capacityand its performance was tested using the four different weights (50, 75, 100 and 150 kg, three different pressures (4, 5 and 6 bar and two different hoses (Ø 6 and Ø 8 mm. By considering experimental results and design criteria, power of the movement mechanism was obtained as 886 Watt. With this study, minimization of energy consumption for movement of passenger cars, and using clean and cheap energy as ATV which can be alternative for single or two passenger vehicles.

  15. Experimentação animal: ética e legislação brasileira Animal experimentation: ethics and the Brazilian legislation

    Directory of Open Access Journals (Sweden)

    Angélica Heringer de Rezende

    2008-04-01

    Full Text Available Este artigo trata da experimentação animal sob os pontos de vista da ética e da política, fazendo uma abordagem histórica do tema no cenário legislativo brasileiro. Os animais de laboratório desempenharam um papel decisivo para o desenvolvimento da ciência e continuam tendo um papel essencial na pesquisa biomédica, no entanto, sua utilização sempre despertou manifestação de diferentes naturezas. Apesar de as primeiras incursões na pesquisa experimental terem sido iniciadas há, pelo menos, quatro séculos, é incipiente o estabelecimento de normas que regulamentem a utilização de animais na América Latina. No Brasil, embora não haja uma lei específica em relação a essa utilização, algumas iniciativas já foram tomadas. As discussões sobre este tema continuam ocorrendo, contudo, a demora para definir uma lei que regulamente o uso de animais em pesquisa tem dificultado a padronização de procedimentos necessários à sistematização dos conhecimentos desenvolvidos no País.This article covers animal experimentation under the viewpoint of ethics and politics, and does a historical review of the theme in the Brazilian legislative scenario. Laboratory animals play a decisive role in the development of science and continue to have an essential role in biomedical research. However, their use always provoked manifestations of different natures. Even though the first incursions in experimental research began at least four centuries ago, the establishment of norms that regulate the use of animals in Latin America is incipient. In Brazil, although a specific law regarding this use does not exist, some initiatives have already been taken. The discussions on this theme continue to happen, however the delay to define a law that regulates the use of animals in research has hindered the standardization of procedures that are necessary to the systematization of the knowledge produced in the country.

  16. Numerical and experimental investigation of bump foil mechanical behaviour

    DEFF Research Database (Denmark)

    Larsen, Jon Steffen; Cerda Varela, Alejandro Javier; Santos, Ilmar

    2014-01-01

    Corrugated foils are utilized in air foil bearings to introduce compliance and damping thus accurate mathematical predictions are important. A corrugated foil behaviour is investigated experimentally as well as theoretically. The experimental investigation is performed by compressing the foil...

  17. Teaching Neurophysiology, Neuropharmacology, and Experimental Design Using Animal Models of Psychiatric and Neurological Disorders

    Science.gov (United States)

    Morsink, Maarten C.; Dukers, Danny F.

    2009-01-01

    Animal models have been widely used for studying the physiology and pharmacology of psychiatric and neurological diseases. The concepts of face, construct, and predictive validity are used as indicators to estimate the extent to which the animal model mimics the disease. Currently, we used these three concepts to design a theoretical assignment to…

  18. Experimental qualification of mechanical and electrical sub-systems of a complex mechanism against fatigue failure

    International Nuclear Information System (INIS)

    Patri, Sudheer; Vijayashree, R.; Rajan Babu, V.; Suresh Kumar, S.; Chandramouli, S.; Meikandamurthy, C.; Prakash, V.; Rajan, K.K.; Srinivasan, G.

    2016-01-01

    Absorber rod drive mechanisms (ARDM) play an important role in ensuring safety of a reactor by rapid insertion of an Absorber rod (AR) during abnormal conditions. Various components/sub-systems of ARDMs, both mechanical and electrical, are subjected to different cyclic loadings during service life. Thus, qualifying these systems against fatigue is an important step for gaining confidence in their safe operation for the design life. ASME in Sec. III, Div. 1, Appendices (Para II - 1500) provides guidelines for the experimental evaluation of the capability of components to withstand cyclic loading. These rules are developed for static components like pressure vessels. Since no such rules are available for moving components like mechanisms, the same were adopted for the ARDMs, with an understanding that the effect of inertia loads of a moving component are to be accounted in the experiments. In application of these rules to a complex mechanisms such as ARDM, various special cases arise which are not addressed explicitly in the code. The paper describes the intelligent adoption of the fatigue life rules given in ASME to various special cases and their extension to electrical systems. The paper also outlines the experiments carried out for qualifying the ARDM against fatigue. (author)

  19. Unraveling the disease consequences and mechanisms of modular structure in animal social networks

    Science.gov (United States)

    Sah, Pratha; Leu, Stephan T.; Cross, Paul C.; Hudson, Peter J.; Bansal, Shweta

    2017-01-01

    Disease risk is a potential cost of group living. Although modular organization is thought to reduce this cost in animal societies, empirical evidence toward this hypothesis has been conflicting. We analyzed empirical social networks from 43 animal species to motivate our study of the epidemiological consequences of modular structure in animal societies. From these empirical studies, we identified the features of interaction patterns associated with network modularity and developed a theoretical network model to investigate when and how subdivisions in social networks influence disease dynamics. Contrary to prior work, we found that disease risk is largely unaffected by modular structure, although social networks beyond a modular threshold experience smaller disease burden and longer disease duration. Our results illustrate that the lowering of disease burden in highly modular social networks is driven by two mechanisms of modular organization: network fragmentation and subgroup cohesion. Highly fragmented social networks with cohesive subgroups are able to structurally trap infections within a few subgroups and also cause a structural delay to the spread of disease outbreaks. Finally, we show that network models incorporating modular structure are necessary only when prior knowledge suggests that interactions within the population are highly subdivided. Otherwise, null networks based on basic knowledge about group size and local contact heterogeneity may be sufficient when data-limited estimates of epidemic consequences are necessary. Overall, our work does not support the hypothesis that modular structure universally mitigates the disease impact of group living.

  20. The radiopharmacological behaviour of Ida-derivatives in normal experimental animals

    International Nuclear Information System (INIS)

    Cox, P.H.

    1981-01-01

    Whilst Technetium-Ida derivatives all show basically similar patterns of biodistribution and as such are suited for cholescintigraphy they nevertheless differ significantly enough from each other to have warranted more detailed comparisons to select the reagent most suited for cholescintigraphy in humans. A review of the basic biological behaviour in animals immediately demonstrates that not only are there observable differences between derivatives but there are also differences in the biological behaviour of any one derivative in different species of animal. Animal data does not therefore directly relate to human biodistribution although many qualitative resemblances can be found. (Auth.)

  1. How to become a top model: impact of animal experimentation on human Salmonella disease research.

    Science.gov (United States)

    Tsolis, Renée M; Xavier, Mariana N; Santos, Renato L; Bäumler, Andreas J

    2011-05-01

    Salmonella serotypes are a major cause of human morbidity and mortality worldwide. Over the past decades, a series of animal models have been developed to advance vaccine development, provide insights into immunity to infection, and study the pathogenesis of human Salmonella disease. The successive introduction of new animal models, each suited to interrogate previously neglected aspects of Salmonella disease, has ushered in important conceptual advances that continue to have a strong and sustained influence on the ideas driving research on Salmonella serotypes. This article reviews important milestones in the use of animal models to study human Salmonella disease and identify research needs to guide future work.

  2. Beagle: an appropriate experimental animal for extrapolating the organ distribution pattern of Th in humans

    International Nuclear Information System (INIS)

    Singh, N.P.; Zimmerman, C.J.; Taylor, G.N.; Wrenn, M.E.

    1988-01-01

    The concentrations and the organ distribution patterns of 228Th, 230Th and 232Th in two 9-y-old dogs of our beagle colony were determined. The dogs were exposed only to background environmental levels of Th isotopes through ingestion (food and water) and inhalation as are humans. The organ distribution patterns of the isotopes in the beagles were compared to the organ distribution patterns in humans to determine if it is appropriate to extrapolate the beagle organ burden data to humans. Among soft tissues, only the lungs, lymph nodes, kidney and liver, and skeleton contained measurable amounts of Th isotopes. The organ distribution pattern of Th isotopes in humans and dog are similar, the majority of Th being in the skeleton of both species. The average skeletal concentrations of 228Th in dogs were 30 to 40 times higher than the average skeletal concentrations of the parent 232Th, whereas the concentration of 228Th in human skeleton was only four to five times higher than 232Th. This suggests that dogs have a higher intake of 228Ra through food than humans. There is a similar trend in the accumulations of 232Th, 230Th and 228Th in the lungs of dog and humans. The percentages of 232Th, 230Th and 228Th in human lungs are 26, 9.7 and 4.8, respectively, compared to 4.2, 2.6 and 0.48, respectively, in dog lungs. The larger percentages of Th isotopes in human lungs may be due simply to the longer life span of humans. If the burdens of Th isotopes in human lungs are normalized to an exposure time of 9.2 y (mean age of dogs at the time of sacrifice), the percent burden of 232Th, 230Th and 228Th in human lungs are estimated to be 3.6, 1.3 and 0.66, respectively. These results suggest that the beagle may be an appropriate experimental animal for extrapolating the organ distribution pattern of Th in humans

  3. Morphostructural characterization of soil conventionally tilled with mechanized and animal traction with and without cover crop

    Directory of Open Access Journals (Sweden)

    Ricardo Ralisch

    2010-12-01

    Full Text Available The structural stability and restructuring ability of a soil are related to the methods of crop management and soil preparation. A recommended strategy to reduce the effects of soil preparation is to use crop rotation and cover crops that help conserve and restore the soil structure. The aim of this study was to evaluate and quantify the homogeneous morphological units in soil under conventional mechanized tillage and animal traction, as well as to assess the effect on the soil structure of intercropping with jack bean (Canavalia ensiformis L.. Profiles were analyzed in April of 2006, in five counties in the Southern-Central region of Paraná State (Brazil, on family farms producing maize (Zea mays L., sometimes intercropped with jack bean. The current structures in the crop profile were analyzed using Geographic Information Systems (GIS and subsequently principal component analysis (PCA to generate statistics. Morphostructural soil analysis showed a predominance of compact units in areas of high-intensity cultivation under mechanized traction. The cover crop did not improve the structure of the soil with low porosity and compact units that hamper the root system growth. In areas exposed to animal traction, a predominance of cracked units was observed, where roots grew around the clods and along the gaps between them.

  4. Mechanisms Involved in Secondary Cardiac Dysfunction in Animal Models of Trauma and Hemorrhagic Shock.

    Science.gov (United States)

    Wilson, Nick M; Wall, Johanna; Naganathar, Veena; Brohi, Karim; De'Ath, Henry D

    2017-10-01

    Clinical evidence reveals the existence of a trauma-induced secondary cardiac injury (TISCI) that is associated with poor patient outcomes. The mechanisms leading to TISCI in injured patients are uncertain. Conversely, animal models of trauma hemorrhage have repeatedly demonstrated significant cardiac dysfunction following injury, and highlighted mechanisms through which this might occur. The aim of this review was to provide an overview of the animal studies describing TISCI and its pathophysiology.Basic science models of trauma show evidence of innate immune system activation via Toll-like receptors, the exact protagonists of which remain unclear. Shortly following trauma and hemorrhage, cardiomyocytes upregulate gene regulatory protein and inflammatory molecule expression including nuclear factor kappa beta, tumor necrosis factor alpha, and interleukin-6. This is associated with expression of membrane bound adhesion molecules and chemokines leading to marked myocardial leukocyte infiltration. This cell activation and infiltration is linked to a rise in enzymes that cause oxidative and nitrative stress and subsequent protein misfolding within cardiomyocytes. Such protein damage may lead to reduced contractility and myocyte apoptosis. Other molecules have been identified as cardioprotective following injury. These include p38 mitogen-activated protein kinases and heat shock proteins.The balance between increasing damaging mediators and a reduction in cardio-protective molecules appears to define myocardial function following trauma. Exogenous therapeutics have been trialled in rodents with promising abilities to favorably alter this balance, and subsequently lead to improved cardiac function.

  5. BIOCHEMICAL SUBSTANTIATION OF COMBINED THERAPY APPLICATION IN THE ACUTE PHASE OF EXPERIMENTAL HELMINTHIASIS OF ANIMALS

    Directory of Open Access Journals (Sweden)

    E. A. Grishina

    2017-01-01

    Full Text Available The purpose of this study was to investigate the influence of the invasion process and different strategies of treatment on some biochemical blood indices of mice infested with Syphacia obvelata and Trichocephalus muris of gastrointestinal tract, in order to optimize etiotropic therapy and improve its efficiency. Materials and methods. In the experiment were used albino mice, divided into the following groups: intact animals (control group; animals infected with Syphacia obvelata; animals infected with Trichocephalus muris; infected animals, who received a single dose of albendazole (7 mg/kg; infected animals, who received a single dose of albendazole (7 mg/kg and gamavit dose intramuscularly (0.3 cm3/kg simultaneously. Blood for the studies was taken from the animals at 1, 3, 7, 10, 14, 17, 21 days after the infection and after drug administration. From biochemical parameters were determined activities of next enzymes: alanine aminotransferase (ALT, aspartate aminotransferase (AST, gamma-glutamyl transferase (γ-GTP and alkaline phosphatase (AP – with kinetic method IFCC. Results. Infecting animals with helminthes caused a noticeable increase in AP and gamma-GTP levels and cytolytic activity of enzymes: ALT and AST compared with intact group. The above-mentioned complex of metabolic changes clearly reveals a disturbance in hepatocyte metabolism that leads to the decrease in detoxifying function of the liver. This can be apparently explained with toxic effects of helminthes waste products. Albendazole mono-therapy in the therapeutic dose (7 mg/kg of mice infected with both Syphacia and Trichocephalus caused an even greater increase in ALT and AST levels and also increased serum levels of alkaline phosphatase and γ-GTP, compared with the control and infected animals, that clearly shows an additional toxic effect from the antihelmintic drug. The use of albendazole in combination with a complex antioxidant “Gamavit” in animals infected with

  6. Iodine based radiopacity of experimental blood clots for testing of mechanical thrombectomy devices

    International Nuclear Information System (INIS)

    Luo, Zhong Hua; Chung, Alex; Choi, Gibok; Lin, Yih Huie; Pang, Huajin; Uchida, Barry T.; Pavcnik, Dusan; Jeromel, Miran; Keller, Frederick S.; Rösch, Josef

    2013-01-01

    Barium sulfate powder used for radiopacity of experimental blood clots (EBCs) for testing mechanical thrombectomy devices (MTD) has negative effects on EBCs mechanical properties. In vitro and in vivo exploration was performed to determine if the iodine based contrast medium will have less negative effects on the EBCs than barium. Fresh blood from 2 swine was used to create fibrinogen enhanced and thrombin initiated EBC in tubes. Iodine radiopacity was achieved by mixing the blood with 65% Iohexol or by soaking the EBCs for 2 or 24 hours in Iohexol. The EBCs opacified with barium served as controls. In vitro study: The EBCs were subjected to four tests, manual elongation, catheter injection, radiopacity and contrast wash out tests. In vivo study: The common carotid arteries of 2 swine were embolized by either barium EBC or EBC soaked for 24 hours in Iohexol. The duration of radiopacity of the different EBCs was compared. The EBCs opacified with Iohexol initially had higher radiopacity than the barium opacified EBCs. However, their opacity rapidly decreased with saline soaking and, particularly, after they were embolized in live animals. The mechanical properties of Iohexol opacified EBCs were inferior to barium opacified EBCs. The Iohexol mixed EBCs were less firm and elastic and half of them fragmented during catheter injection. The Iohexol soaked EBCs exhibited decreased tensile strength and elasticity compared to the barium EBCs. Compared to barium, iodine based contrast medium does not offer any advantage for opacifying EBCs

  7. Intervertebral Foramen Injection of Ozone Relieves Mechanical Allodynia and Enhances Analgesic Effect of Gabapentin in Animal Model of Neuropathic Pain.

    Science.gov (United States)

    Luo, Wen-Jun; Yang, Fan; Yang, Fei; Sun, Wei; Zheng, Wei; Wang, Xiao-Liang; Wu, Fang-Fang; Wang, Jiang-Lin; Wang, Jia-Shuang; Guan, Su-Min; Chen, Jun

    2017-07-01

    In a 5-year follow-up study in a hospital in southern China, it was shown that intervertebral foramen (IVF) injection of ozone at the involved segmental levels could significantly alleviate paroxysmal spontaneous pain and mechanical allodynia in patients with chronic, intractable postherpetic neuralgia (PHN) and improve the quality of life. However, so far no proof-of-concept studies in animals have been available. This study was designed to investigate whether IVF ozone has an analgesic effect on animal models of neuropathic and inflammatory pain. Experimental trial in rats. Institute for Biomedical Sciences of Pain. By IVF injection, a volume of 50 µl containing 30 µg/mL ozone-oxygen mixture or 50 µl air was carried out on male Sprague-Dawley rats of naïve, inflammatory pain states produced by injections of either bee venom or complete Freud's adjuvant, and neuropathic pain state produced by spared nerve injury, respectively. The effects of IVF ozone on pain-related behaviors were evaluated for 2 weeks or one month. Then combined use of gabapentin (100 mg/1 kg body weight) with IVF ozone was evaluated in rats with neuropathic pain by intraperitoneal administration 5 days after the ozone treatment. Finally, the analgesic effects of another 4 drugs, AMD3100 (a CXCR4 antagonist), A-803467 (a selective Nav1.8 blocker), rapamycin (the mTOR inhibitor), and MGCD0103 (a selective histone deacetylase inhibitor) were evaluated for long term through IVF injection, respectively. (1) IVF injection of ozone at L4-5 was only effective in suppression of mechanical allodynia in rats with neuropathic pain but not with inflammatory pain; (2) the analgesic effects of IVF ozone lasted much longer (> 14 days) than other selective molecular target drugs (bee venom, complete Freud's adjuvant.

  8. Studies on food in experimental animal and possible role of irradiation detoxification

    International Nuclear Information System (INIS)

    EL-Shennawy, H.M.

    1998-01-01

    Rapeseed is one of the important oilseed crops in the far east and in the northern parts of europe and north america (daun and bushuk 1983). It was introduce to egypt during 1980 by the agriculture research center, ministry of agriculture, egypt (moharam et al., 1982). rapeseed is mainly used as a source of oil and its meal used as animal feed and it could be used as a potential source of a protein. The oil content ranges from 33.2 to 476% and protein content from 29.5 to 57.5% (Anjou et al., 1977). Rapeseed contains some biologically active substances, which act as anti nutritional factors glucosinolates and their hydrolysis products have presented a major obstacle to the utilization of rapeseed meal in animal or human nutrition. They have been implicated in several physiological disorders in animal including goiter and haemorrhagic liver syndrome

  9. Experimental econophysics properties and mechanisms of laboratory markets

    CERN Document Server

    Huang, Ji-Ping

    2015-01-01

    Experimental Econophysics describes the method of controlled human experiments, which is developed by physicists to study some problems in economics or finance, namely, stylized facts, fluctuation phenomena, herd behavior, contrarian behavior, hedge behavior, cooperation, business cycles, partial information, risk management, and stock prediction. Experimental econophysics together with empirical econophysics are two branches of the field of econophysics. The latter one has been extensively discussed in the existing books, while the former one has been seldom touched. In this book, the author will focus on the branch of experimental econophysics. Empirical econophysics is based on the analysis of data in real markets by using some statistical tools borrowed from traditional statistical physics. Differently, inspired by the role of controlled experiments and system modelling (for computer simulations and/or analytical theory) in developing modern physics, experimental econophysics specially relies on controlle...

  10. Evaluation of photon-absorptiometry for determination of bone mineral content in experimental animals

    International Nuclear Information System (INIS)

    Krasznai, I.; Szathmary, M.; Horvath, Cs.; Hollo, G.; Fabu, G.

    1994-01-01

    Instruments commonly used for determination of bone mineral content in human were evaluated for their use in small laboratory animals. By measuring bone phantoms and rat femurs in vitro, authors found 0.015 and 0.034 g/cm sensitivity for (SPA) and (DEXA) methods, respectively. High reproducibility was obtained, with values of relative standard deviations being <2 and approximately 4% for SPA and DEXA, respectively. Both techniques were found suitable for determination of bone mineral content of laboratory animals, but DEXA is suggested as the preferred method for evaluations under in vivo circumstances. (N.T.)

  11. Pathomorphological features of the skin and muscle tissue of experimental animals in the case of lifetime and postmortem damage

    Directory of Open Access Journals (Sweden)

    A. V. Kis

    2013-04-01

    Full Text Available The problem of forensic medical diagnosis of tissue injury is currently the subject of numerous investigations. Pathomorphological changes of the skin and muscle tissue of experimental animals, resulting in the case of lifetime and postmortem traumatic injuries, depending on the time and temperature, were revealed by the author. Data obtained by the author is very necessary for improving the forensic medical diagnosis of traumatic soft tissue injuries.

  12. An experimental analysis of fracture mechanisms by acoustic ...

    African Journals Online (AJOL)

    Afin d'analyser le comportement mécanique globale de l'assemblage, des essais de traction .... named as Groups A, B and C (Tab. 5). Table.1: Mechanical properties of epoxy matrix Vicotex 914. Table.2: Mechanical properties of fibers T300. Young. 's modul us. E. Poisson's ratio. Ν shear modulus. G. Tensile strength yield.

  13. The Effectiveness of Health Animations in Audiences With Different Health Literacy Levels : An Experimental Study

    NARCIS (Netherlands)

    Meppelink, Corine S.; van Weert, Julia C. M.; Haven, Carola J.; Smit, Edith G.

    Background: Processing Web-based health information can be difficult, especially for people with low health literacy. Presenting health information in an audiovisual format, such as animation, is expected to improve understanding among low health literate audiences. Objective: The aim of this paper

  14. The effects of radiation on the diseases of aging in experimental animals: gerontological significance

    International Nuclear Information System (INIS)

    Hollander, C.F.; Zwieten, M.J. van; Broerse, J.J.

    1979-01-01

    A study of the effect of different types and doses of ionizing radiation on the induction of mammary tumours in rats and the role of ovarian hormones in tumour indication is reported. The occurrence of other diseases in the irradiated animals is also studied and compared to those occurring in non-irradiated controls. (Auth.)

  15. Sensitivity analysis by experimental design and metamodelling : case study on simulation in national animal disease control

    NARCIS (Netherlands)

    Vonk Noordegraaf, A.; Nielen, M.; Kleijnen, J.P.C.

    2003-01-01

    Simulation is a frequently applied tool in the discipline of animal health economics. Application of sensitivity analysis, however, is often limited to changing only one factor at a time (OAT designs). In this study, the statistical techniques of Design of Experiments (DOE) and regression

  16. Pneumothorax monitoring by remittance measurement: Comparison between experimental model and animal studies

    NARCIS (Netherlands)

    Beek, J. F.; Menovsky, T.; van Straaten, H. L.; Sterenborg, H. J.; Koppe, J. G.; van Gemert, M. J.

    1999-01-01

    Pneumothorax monitoring by remittance measurement in neonatology is investigated using model experiments. The results are compared to previous animal experiments. A multifibre probe is used to measure the change in remittance at 632.8 nm and 790 nm as a function of the thickness of a layer of air

  17. Reducing animal experimentation in foot-and-mouth disease vaccine potency tests.

    Science.gov (United States)

    Reeve, Richard; Cox, Sarah; Smitsaart, Eliana; Beascoechea, Claudia Perez; Haas, Bernd; Maradei, Eduardo; Haydon, Daniel T; Barnett, Paul

    2011-07-26

    The World Organisation for Animal Health (OIE) Terrestrial Manual and the European Pharmacopoeia (EP) still prescribe live challenge experiments for foot-and-mouth disease virus (FMDV) immunogenicity and vaccine potency tests. However, the EP allows for other validated tests for the latter, and specifically in vitro tests if a "satisfactory pass level" has been determined; serological replacements are also currently in use in South America. Much research has therefore focused on validating both ex vivo and in vitro tests to replace live challenge. However, insufficient attention has been given to the sensitivity and specificity of the "gold standard"in vivo test being replaced, despite this information being critical to determining what should be required of its replacement. This paper aims to redress this imbalance by examining the current live challenge tests and their associated statistics and determining the confidence that we can have in them, thereby setting a standard for candidate replacements. It determines that the statistics associated with the current EP PD(50) test are inappropriate given our domain knowledge, but that the OIE test statistics are satisfactory. However, it has also identified a new set of live animal challenge test regimes that provide similar sensitivity and specificity to all of the currently used OIE tests using fewer animals (16 including controls), and can also provide further savings in live animal experiments in exchange for small reductions in sensitivity and specificity. Copyright © 2011 Elsevier Ltd. All rights reserved.

  18. The effectiveness of health animations in audiences with different health literacy levels: An experimental study

    NARCIS (Netherlands)

    Meppelink, C.S.; van Weert, J.C.M.; Haven, C.J.; Smit, E.G.

    2015-01-01

    Background: Processing Web-based health information can be difficult, especially for people with low health literacy. Presenting health information in an audiovisual format, such as animation, is expected to improve understanding among low health literate audiences. Objective: The aim of this paper

  19. Experimental protocols for behavioral imaging: seeing animal models of drug abuse in a new light.

    Science.gov (United States)

    Aarons, Alexandra R; Talan, Amanda; Schiffer, Wynne K

    2012-01-01

    Behavioral neuroimaging is a rapidly evolving discipline that represents a marriage between the fields of behavioral neuroscience and preclinical molecular imaging. This union highlights the changing role of imaging in translational research. Techniques developed for humans are now widely applied in the study of animal models of brain disorders such as drug addiction. Small animal or preclinical imaging allows us to interrogate core features of addiction from both behavioral and biological endpoints. Snapshots of brain activity allow us to better understand changes in brain function and behavior associated with initial drug exposure, the emergence of drug escalation, and repeated bouts of drug withdrawal and relapse. Here we review the development and validation of new behavioral imaging paradigms and several clinically relevant radiotracers used to capture dynamic molecular events in behaving animals. We will discuss ways in which behavioral imaging protocols can be optimized to increase throughput and quantitative methods. Finally, we discuss our experience with the practical aspects of behavioral neuroimaging, so investigators can utilize effective animal models to better understand the addicted brain and behavior.

  20. Ethical Issues Associated with the Use of Animal Experimentation in Behavioral Neuroscience Research

    NARCIS (Netherlands)

    Ohl, Frauke; Meijboom, Franck

    2015-01-01

    This chapter briefly explores whether there are distinct characteristics in the field of Behavioral Neuroscience that demand specific ethical reflection. We argue that although the ethical issues in animal-based Behavioral Neuroscience are not necessarily distinct from those in other research

  1. Experimental Analysis of Tensile Mechanical Properties of Sprayed FRP

    Directory of Open Access Journals (Sweden)

    Zhao Yang

    2016-01-01

    Full Text Available To study the tensile mechanical properties of sprayed FRP, 13 groups of specimens were tested through uniaxial tensile experiments, being analyzed about stress-strain curve, tensile strength, elastic modulus, breaking elongation, and other mechanical properties. Influencing factors on tensile mechanical properties of sprayed FRP such as fiber type, resin type, fiber volume ratio, fiber length, and composite thickness were studied in the paper too. The results show that both fiber type and resin type have an obvious influence on tensile mechanical properties of sprayed FRP. There will be a specific fiber volume ratio for sprayed FRP to obtain the best tensile mechanical property. The increase of fiber length can lead to better tensile performance, while that of composite thickness results in property degradation. The study can provide reference to popularization and application of sprayed FRP material used in structure reinforcement.

  2. Experimental studies of animal social learning in the wild: Trying to untangle the mystery of human culture.

    Science.gov (United States)

    Hill, Kim

    2010-08-01

    Here I discuss how studies on animal social learning may help us understand human culture. It is an evolutionary truism that complex biological adaptations always evolve from less complex but related adaptations, but occasionally evolutionary transitions lead to major biological changes whose end products are difficult to anticipate. Language-based cumulative adaptive culture in humans may represent an evolutionary transition of this type. Most of the social learning observed in animals (and even plants) may be due to mechanisms that cannot produce cumulative cultural adaptations. Likewise, much of the critical content of socially transmitted human culture seems to show no parallel in nonhuman species. Thus, with regard to the uniquely human extent and quality of culture, we are forced to ask: Are other species only a few small steps away from this transition, or do they lack multiple critical features that make us the only truly cultural species? Only future research into animal social learning can answer these questions.

  3. Mechanical behaviour of the heel pad: experimental and numerical approach

    DEFF Research Database (Denmark)

    Matteoli, Sara; Fontanella, C. G.; Virga, A.

    The aim of the present work was to investigate the stress relaxation phenomena of the heel pad region under different loading conditions. A 31-year-old healthy female was enrolled in this study and her left foot underwent both MRI and experimental compression tests. Experimental results were...... compared with those obtained from finite element analysis performed on numerical 3D subject-specific heel pad model built on the basis of MRI. The calcaneal fat pad tissue was described with a visco-hyperelastic model, while a fiber-reinforced hyperelastic model was formulated for the skin. The reliability...

  4. Neuroendocrine mechanisms of development of experimental hyperandrogen-induced anovulation.

    Science.gov (United States)

    Reznikov, A G; Sinitsyn, P V; Tarasenko, L V; Polyakova, L I

    2003-10-01

    An experimental model of hyperandrogen-induced anovulatory infertility (s.c. implantation of Silastic capsules containing testosterone into adult female rats) was used to study morphological, hormonal, and biochemical measures characterizing the state of the hypothalamo-hypophyseal-ovarian system. Impairments in functional androgen metabolism in the hypothalamus were seen, with decreases in the Luliberin sensitivity of the hypophysis, changes in the structure of estral cycles, and morphological changes in the ovaries; these findings are evidence for neuroendocrine disturbances in the control of ovulation. Flutamide, an experimental antiandrogen, led to partial normalization of the hormonal, biochemical, and morphological characteristics, as well as to recovery of fertility in females with anovulatory infertility.

  5. An experimental analysis of fracture mechanisms by acoustic ...

    African Journals Online (AJOL)

    This work is focused on the study of the evolution of damage mode and failure mechanisms of woven composite bolted assembly carbon fiber/epoxy. In the present paper three configurations are studied [0°,45°,0°,45°], [0°,45°,0°,45°]s and [0°,45°,0°,45,0°]s. In order to analyze a global mechanical behavior of the assembly, ...

  6. Holostrain system: a powerful tool for experimental mechanics

    Science.gov (United States)

    Sciammarella, Cesar A.; Bhat, Gopalakrishna K.

    1992-09-01

    A portable holographic interferometer that can be used to measure displacements and strains in all kinds of mechanical components and structures is described. The holostrain system captures images on a TV camera that detects interference patterns produced by laser illumination. The video signals are digitized. The digitized interferograms are processed by a fast processing system. The output of the system are the strains or the stresses of the observed mechanical component or structure.

  7. Histologic alterations of the normal bladder wall following to variably fractionated irradiation - an experimentation on animals

    International Nuclear Information System (INIS)

    Fueller, J.; Fritzsche, V.; Kob, D.; Arndt, J.; Kriester, A.; Friedrich-Schiller-Universitaet, Jena

    1986-01-01

    The histopathologic alterations of the bladder wall were investigated in 180 rabbits irradiated with different fractionations and total focal doses. Animals sacrified one week after the end of irradiation showed alterations of the urothelium (desquamation, increased polymorphism of nuclei vacuolizations) as well as oedematous and hyperemic reactions in submucosa and muscularis. These alterations became stronger when the single and total focal dose and the ret values were increased. Animals sacrified three to six months after the end of irradiation showed dystrophic-sclerotic processes as well as vascular obliterations in the submucosa and muscularis. The alterations were only clearly visible in case of a total focal dose of at least 30 Gy. With regard to a minimization of histopathologic alterations of the bladder wall, a fractionation of 1.5 Gy per day has to be considered as favorable in radiotherapy of the carcinoma of the urinary bladder. (orig.) [de

  8. Evaluation of analgesic and anti-inflammatory activity of a combination of tramadol-ibuprofen in experimental animals

    Directory of Open Access Journals (Sweden)

    Chidambarann Suthakaran

    2017-01-01

    Full Text Available Background: Pain is the major concern of patients attending dental clinics, and satisfactory pain relief has always been difficult to achieve. Since the pathophysiology of pain is a complex, central and peripheral nervous system process, combined analgesic regimens with different mechanisms of action as a multimodal approach are becoming popular among the clinicians and dentists. Objectives: The aim of the present study was to evaluate the analgesic and anti-inflammatory activity of ibuprofen and tramadol when used alone or in combination in animal models of pain and inflammation. Animals and Methods: The animals were divided into six groups with six animals in each group. Analgesic activity was assessed by hot plate method in rats and by acetic acid-induced writhing test in mice. Paw edema model in rats after induction with 0.1 mL of 1% carrageenan was used to assess the anti-inflammatory activity. Statistical Analysis: Analysis of variance followed by Tukey's honestly significant difference post hoc test was used for statistical analysis. Results and Conclusion: Combined use of tramadol and ibuprofen provided enhanced analgesic and anti-inflammatory effects in animal models of pain and inflammation.

  9. Cariogenicity Of Different Types Of Milk: An Experimental Study Using Animal Model.

    OpenAIRE

    Peres R.C.; Coppi L.C.; Franco E.M.; Volpato M.C.; Groppo F.C.; Rosalen P.L.

    2002-01-01

    This study evaluated the cariogenic potential of infant formulas and cow's milk, using a high cariogenic challenge in the animal model. Sixty female Wistar rats infected with Streptococcus sobrinus and desalivated were randomly divided into 6 groups, which received ad libitum: 1) sterilized deionized distilled water (SDW) with 5% sucrose; 2) cow's milk; 3) Nan 2; 4) Nestogeno 2; 5) Ninho growth supporting; 6) SDW. Groups 1 and 6 also received essential diet NCP#2 by gavage, twice a day. After...

  10. Indirect caudal lymphography using a new water-soluble contrast agent - animal experimental studies in pigs

    International Nuclear Information System (INIS)

    Apitzsch, D.E.; Kroll, H.U.; Zuehlke, H.V.

    1981-01-01

    Animal experiments on caudal lymphography in pigs are presented, using a new water-soluble contrast medium which is renally excreted. Indirect cutaneous administration renders possible the radiological visualization of the entire lymphatic drainage system of the lower limb, the retro-peritoneal space and the thoracic duct. Visualization of the lymphatic system is rapid, homogeneous and can be repeated as often as desired. The quality of the lymphogram is as good as that obtained by the current methods in common use. (orig.)

  11. Sutureless vascular anastomoses by N-butyl-2 cyanoacrylate adhesive: an experimental animal study.

    Science.gov (United States)

    Saba, D; Yilmaz, M; Yavuz, H; Noyan, S; Avci, B; Ercan, A; Ozkan, H; Cengiz, M

    2007-01-01

    The purpose of this animal study was to find out whether sutureless anastomoses using N-butyl-2-cyanoacrylate were effective in the suppression of neointimal hyperplasia or not. Ten male adult mongrel dogs were used in this animal study. The animals were randomly divided into a control group (n = 5) and a study group (n = 5). The study group underwent sutureless anastomoses using N-buthyl-2-cyanoacrylate adhesive. Infrarenal aortoaortic graft was interposed using polytetrafluoroethylene. In the study group, the mean intimal thickness at the proximal anastomosis was 27.4 +/- 1.94 microm and 27.4 +/- 1.51 microm at the distal anastomosis. In the control group, the mean intimal thickness was 138.4 +/- 5.02 mum at the proximal anastomosis and 67.6 +/- 6.42 microm at the distal anastomosis. Intimal thickness at the proximal and distal anastomoses in the control group was significantly (p anastomoses using with N-butyl-2-cyanoacrylate adhesive might be a good alternative to conventional suture technique. Copyright 2007 S. Karger AG, Basel.

  12. Brownian motion or Lévy walk? Stepping towards an extended statistical mechanics for animal locomotion.

    Science.gov (United States)

    Gautestad, Arild O

    2012-09-07

    Animals moving under the influence of spatio-temporal scaling and long-term memory generate a kind of space-use pattern that has proved difficult to model within a coherent theoretical framework. An extended kind of statistical mechanics is needed, accounting for both the effects of spatial memory and scale-free space use, and put into a context of ecological conditions. Simulations illustrating the distinction between scale-specific and scale-free locomotion are presented. The results show how observational scale (time lag between relocations of an individual) may critically influence the interpretation of the underlying process. In this respect, a novel protocol is proposed as a method to distinguish between some main movement classes. For example, the 'power law in disguise' paradox-from a composite Brownian motion consisting of a superposition of independent movement processes at different scales-may be resolved by shifting the focus from pattern analysis at one particular temporal resolution towards a more process-oriented approach involving several scales of observation. A more explicit consideration of system complexity within a statistical mechanical framework, supplementing the more traditional mechanistic modelling approach, is advocated.

  13. Effects of flunixin meglumine on experimental tendon wound healing: A histopathological and mechanical study in rabbits

    Directory of Open Access Journals (Sweden)

    Mehdi Behfar

    2014-12-01

    Full Text Available Tendons are frequently targets of injury in sports and work. Whether nonsteroidal anti-inflammatory drugs (NSAIDs have beneficial effects on tendon healing is still a matter of debate. This study was conducted to evaluate effects of flunixin meglumine (FM on tendon healing after experimentally induced acute trauma. Twenty eight adult male New Zealand White rabbits were subjected to complete transection of deep digital flexor tendons followed by suture placement. Treatment group received intramuscular injection of FM for three days, and controls received placebo. Subsequently, cast immobilization was continued for two weeks. Animals were sacrificed four weeks after surgery and tissue samples were taken. The histological evaluations revealed improved structural characteristics of neotendon formation including fibrillar linearity, fibrillar continuity and neovascularization in treatment group compared to those of controls (p 0.05. Mechanical evaluation revealed significant increase in load-related material properties including ultimate load, yield load, energy absorption and ultimate stress in treatment group compared to those of control group (p 0.05. The present study showed that intramuscular injection of FM resulted in improved structural and mechanical properties of tendon repairs and it could be an effective treatment for acute tendon injuries like severance and laceration.

  14. Is there a need for special preventive medical check-ups in employees exposed to experimental animal dust?

    Science.gov (United States)

    Schmid, Klaus; Jüngert, Barbara; Hager, Meta; Drexler, Hans

    2009-02-01

    Due to new legal requirements in Germany, the employer must request preventive medical check-ups for activities involving exposure to dust from experimental animals in the rooms in which the animals are kept. The objective is to report our first experiences with these medical check-ups in the context of academic research. The check-ups were carried out since November 2005 and comprised a questionnaire and a medical examination, including a pulmonary function test with whole-body plethysmography. Respiratory, nasal and ocular symptoms related to occupational exposure to animals were documented. Participation in skin prick tests (ubiquitous inhalation allergens and laboratory animal allergens), a bronchial provocation test with methacholine, and serological examinations for total IgE and specific IgE antibodies was voluntary. Data on 132 persons are presented. One hundred and six of these had already been exposed for at least 1 year. Main complaints at the workplace were sneezing and runny nose. Ocular symptoms and bronchial asthma were reported infrequently. The development of at least one of these symptoms occurred in 34% of employees with an exposure of at least 1 year. If the weekly exposure duration was at least 5 h, the proportion of employees with complaints rose to 44.9%. In employees occupationally exposed to mice and rats, work-related complaints occurred in 33.7 and 37.8%, respectively, and sensitisation rates were 12.7 and 16.3%, respectively. Employees with and without complaints differed in history of allergic symptoms, and workplace safety measures. In employees with occupational contact with laboratory animal dust, the frequency of complaints was high. The results confirm the necessity of regular medical check-ups for employees with contact with laboratory animal dust. Nevertheless, the medical check-ups must be part of a prevention strategy including education, engineering controls, administrative controls, use of personal protective equipment and

  15. Constructive anthropomorphism: a functional evolutionary approach to the study of human-like cognitive mechanisms in animals.

    Science.gov (United States)

    Arbilly, Michal; Lotem, Arnon

    2017-10-25

    Anthropomorphism, the attribution of human cognitive processes and emotional states to animals, is commonly viewed as non-scientific and potentially misleading. This is mainly because apparent similarity to humans can usually be explained by alternative, simpler mechanisms in animals, and because there is no explanatory power in analogies to human phenomena when these phenomena are not well understood. Yet, because it is also difficult to preclude real similarity and continuity in the evolution of humans' and animals' cognitive abilities, it may not be productive to completely ignore our understanding of human behaviour when thinking about animals. Here we propose that in applying a functional approach to the evolution of cognitive mechanisms, human cognition may be used to broaden our theoretical thinking and to generate testable hypotheses. Our goal is not to 'elevate' animals, but rather to find the minimal set of mechanistic principles that may explain 'advanced' cognitive abilities in humans, and consider under what conditions these mechanisms were likely to enhance fitness and to evolve in animals. We illustrate this approach, from relatively simple emotional states, to more advanced mechanisms, involved in planning and decision-making, episodic memory, metacognition, theory of mind, and consciousness. © 2017 The Author(s).

  16. Experimental Platform for Ultra-high Dose Rate FLASH Irradiation of Small Animals Using a Clinical Linear Accelerator

    Energy Technology Data Exchange (ETDEWEB)

    Schüler, Emil; Trovati, Stefania; King, Gregory; Lartey, Frederick; Rafat, Marjan; Villegas, Manuel; Praxel, A. Joe [Department of Radiation Oncology, Stanford University School of Medicine, Stanford, California (United States); Loo, Billy W., E-mail: BWLoo@stanford.edu [Department of Radiation Oncology, Stanford University School of Medicine, Stanford, California (United States); Stanford Cancer Institute, Stanford University School of Medicine, Stanford, California (United States); Maxim, Peter G., E-mail: PMaxim@stanford.edu [Department of Radiation Oncology, Stanford University School of Medicine, Stanford, California (United States); Stanford Cancer Institute, Stanford University School of Medicine, Stanford, California (United States)

    2017-01-01

    Purpose: A key factor limiting the effectiveness of radiation therapy is normal tissue toxicity, and recent preclinical data have shown that ultra-high dose rate irradiation (>50 Gy/s, “FLASH”) potentially mitigates this effect. However, research in this field has been strongly limited by the availability of FLASH irradiators suitable for small animal experiments. We present a simple methodologic approach for FLASH electron small animal irradiation with a clinically available linear accelerator (LINAC). Methods and Materials: We investigated the FLASH irradiation potential of a Varian Clinac 21EX in both clinical mode and after tuning of the LINAC. We performed detailed FLUKA Monte Carlo and experimental dosimetric characterization at multiple experimental locations within the LINAC head. Results: Average dose rates of ≤74 Gy/s were achieved in clinical mode, and the dose rate after tuning exceeded 900 Gy/s. We obtained 220 Gy/s at 1-cm depth for a >4-cm field size with 90% homogeneity throughout a 2-cm-thick volume. Conclusions: We present an approach for using a clinical LINAC for FLASH irradiation. We obtained dose rates exceeding 200 Gy/s after simple tuning of the LINAC, with excellent dosimetric properties for small animal experiments. This will allow for increased availability of FLASH irradiation to the general research community.

  17. Experimental Platform for Ultra-high Dose Rate FLASH Irradiation of Small Animals Using a Clinical Linear Accelerator.

    Science.gov (United States)

    Schüler, Emil; Trovati, Stefania; King, Gregory; Lartey, Frederick; Rafat, Marjan; Villegas, Manuel; Praxel, A Joe; Loo, Billy W; Maxim, Peter G

    2017-01-01

    A key factor limiting the effectiveness of radiation therapy is normal tissue toxicity, and recent preclinical data have shown that ultra-high dose rate irradiation (>50 Gy/s, "FLASH") potentially mitigates this effect. However, research in this field has been strongly limited by the availability of FLASH irradiators suitable for small animal experiments. We present a simple methodologic approach for FLASH electron small animal irradiation with a clinically available linear accelerator (LINAC). We investigated the FLASH irradiation potential of a Varian Clinac 21EX in both clinical mode and after tuning of the LINAC. We performed detailed FLUKA Monte Carlo and experimental dosimetric characterization at multiple experimental locations within the LINAC head. Average dose rates of ≤74 Gy/s were achieved in clinical mode, and the dose rate after tuning exceeded 900 Gy/s. We obtained 220 Gy/s at 1-cm depth for a >4-cm field size with 90% homogeneity throughout a 2-cm-thick volume. We present an approach for using a clinical LINAC for FLASH irradiation. We obtained dose rates exceeding 200 Gy/s after simple tuning of the LINAC, with excellent dosimetric properties for small animal experiments. This will allow for increased availability of FLASH irradiation to the general research community. Copyright © 2016 Elsevier Inc. All rights reserved.

  18. Experimental study on mechanical properties of three steels

    OpenAIRE

    Wen X.J.; Lu F.Y.; Lin Y.L.; Qin J.G.

    2012-01-01

    Tensile properties of three steels named A, B, and C were investigated. The quasi-static experiments were carried out by using WDW-100D computer control testing machine while the high strain-rate experiments were testing by using the Split Hopkinson Tensile Bars (SHTB). The stress-strain curves of the materials were obtained, tensile strength, elongation, and energy dissipated were acquired. From the experimental results, the Jonson-Cook constitutive model was use to describe the behaviours o...

  19. Experimental hydrocephalus following mechanical increment of intraventricular pulse pressure.

    Science.gov (United States)

    Di Rocco, C; Pettorossi, V E; Caldarelli, M; Mancinelli, R; Velardi, F

    1977-11-15

    Experimental hydrocephalus has been induced in lambs by artificial increase of the amplitude of intraventricular cerebrospinal fluid (CSF) oscillations related to arterial pulsations, without concomitant changes of the mean CSF-pressure. The characteristics of this hydrocephalus demonstrate that the intraventricular CSF-pulsations can play a role in the genesis of ventricular dilation. Such a method may be used to produce an original model of hydrocephalus independent of changes of CSF-circulation or absorption.

  20. Pathological mechanism of musculoskeletal manifestations associated with CRPS type II: an animal study.

    Science.gov (United States)

    Ota, Hideyuki; Arai, Tetsuya; Iwatsuki, Katsuyuki; Urano, Hideki; Kurahashi, Toshikazu; Kato, Shuichi; Yamamoto, Michiro; Hirata, Hitoshi

    2014-10-01

    Patients with complex regional pain syndrome (CRPS) often complain of abnormal sensations beyond the affected body part, but causes of this spread of musculoskeletal manifestations into contiguous areas remain unclear. In addition, immobilization can predispose to the development of CRPS. We examined functional, biochemical, and histological alterations in affected parts, including contiguous zones, using an animal model. Ten-week-old male Wistar rats were assigned to 5 groups: a normal group receiving no treatment, a sham operation group with surgical exploration, an immobilization group with surgical exploration plus internal knee joint immobilization, a surgical neuropathy group prepared by spinal nerve ligation (SNL) of the left L5 nerve root, and a surgical neuropathy+immobilization group with simultaneous SNL and knee joint immobilization. Mechanical allodynia and knee contracture were compared between groups, and tissues were harvested for histological assessments and gene and protein expression analyses. Neither surgical procedures nor immobilization induced detectable mechanical sensitivity. However, the addition of nerve injury resulted in detectable mechanical allodynia, and immobilization not only accelerated hyperalgesia, but also resulted in muscle fibrosis. Nerve growth factor (NGF) and other mediators of neurogenic inflammation were highly expressed not only in denervated muscles, but also in innervated muscles in contiguous areas, suggesting the spread of NGF production beyond the myotome of the injured nerve. Transforming growth factor β was involved in the development of contracture in CRPS. These findings imply that neuroinflammatory components play major roles in the progression and dispersion of both sensory pathologies and pathologies that are exacerbated by immobilization. Copyright © 2014 International Association for the Study of Pain. Published by Elsevier B.V. All rights reserved.

  1. An Experimental Study to Measure the Mechanical Properties of the Human Liver.

    Science.gov (United States)

    Karimi, Alireza; Shojaei, Ahmad

    2018-01-01

    Since the liver is one of the most important organs of the body that can be injured during trauma, that is, during accidents like car crashes, understanding its mechanical properties is of great interest. Experimental data is needed to address the mechanical properties of the liver to be used for a variety of applications, such as the numerical simulations for medical purposes, including the virtual reality simulators, trauma research, diagnosis objectives, as well as injury biomechanics. However, the data on the mechanical properties of the liver capsule is limited to the animal models or confined to the tensile/compressive loading under single direction. Therefore, this study was aimed at experimentally measuring the axial and transversal mechanical properties of the human liver capsule under both the tensile and compressive loadings. To do that, 20 human cadavers were autopsied and their liver capsules were excised and histologically analyzed to extract the mean angle of a large fibers population (bundle of the fine collagen fibers). Thereafter, the samples were cut and subjected to a series of axial and transversal tensile/compressive loadings. The results revealed the tensile elastic modulus of 12.16 ± 1.20 (mean ± SD) and 7.17 ± 0.85 kPa under the axial and transversal loadings respectively. Correspondingly, the compressive elastic modulus of 196.54 ± 13.15 and 112.41 ± 8.98 kPa were observed under the axial and transversal loadings respectively. The compressive axial and transversal maximum/failure stress of the capsule were 32.54 and 37.30 times higher than that of the tensile ones respectively. The capsule showed a stiffer behavior under the compressive load compared to the tensile one. In addition, the axial elastic modulus of the capsule was found to be higher than that of the transversal one. The findings of the current study have implications not only for understanding the mechanical properties of the human capsule tissue under tensile

  2. Design standards for experimental and field studies to evaluate diagnostic accuracy of tests for infectious diseases in aquatic animals.

    Science.gov (United States)

    Laurin, E; Thakur, K K; Gardner, I A; Hick, P; Moody, N J G; Crane, M S J; Ernst, I

    2018-05-01

    Design and reporting quality of diagnostic accuracy studies (DAS) are important metrics for assessing utility of tests used in animal and human health. Following standards for designing DAS will assist in appropriate test selection for specific testing purposes and minimize the risk of reporting biased sensitivity and specificity estimates. To examine the benefits of recommending standards, design information from published DAS literature was assessed for 10 finfish, seven mollusc, nine crustacean and two amphibian diseases listed in the 2017 OIE Manual of Diagnostic Tests for Aquatic Animals. Of the 56 DAS identified, 41 were based on field testing, eight on experimental challenge studies and seven on both. Also, we adapted human and terrestrial-animal standards and guidelines for DAS structure for use in aquatic animal diagnostic research. Through this process, we identified and addressed important metrics for consideration at the design phase: study purpose, targeted disease state, selection of appropriate samples and specimens, laboratory analytical methods, statistical methods and data interpretation. These recommended design standards for DAS are presented as a checklist including risk-of-failure points and actions to mitigate bias at each critical step. Adherence to standards when designing DAS will also facilitate future systematic review and meta-analyses of DAS research literature. © 2018 John Wiley & Sons Ltd.

  3. Deposition, translocation and effects of transuranic particles inhaled by experimental animals

    International Nuclear Information System (INIS)

    Craig, D.K.; Ballou, J.E.; Dagle, G.E.; Mahlum, D.D.; Park, J.F.; Sanders, C.L.; Sikov, M.R.; Stuart, B.O.

    1977-01-01

    Inhalation exposure constitutes the most likely route of entrance for transuranics into the body. Cancer is the most likely consequence of exposure, but several thousand workers have been exposed during the last 30 yrs without, so far, evidence of exposure-related effects. Several soluble and insoluble transuranic compounds have been studied in rodents and dogs, either alone or combined with exposure to other materials (e.g., PuO/sub 2/--UO/sub 2/ fuel and Na). These studies have provided a wide variety of spatial and temporal dose distribution patterns in the lung. The distribution and total initial deposition in the respiratory tract is a function of the physical characteristics of the inhaled aerosols (size distribution, shape, hygroscopicity) and of the morphology and physiology of the animal. Translocation rates, organ and tissue distribution and excretion in urine and feces, are a function of the physicochemical characteristics of the deposited material (solubility, specific activity, chemical compound, etc.). Differences in rate of translocation of the solubilized material, primarily to the liver and bone, determines the radiation dose to the various tissues involved. Insoluble particles of plutonium dioxide are transferred to the thoracic lymph nodes, which may be functionally destroyed as a consequence. Radiation pneumonitis and pulmonary fibrosis are the main causes of death in animals with cumulative radiation doses to the lung of a few thousand rads. The most significant long-term effect of inhaled transuranic compounds in animals is the development of lung and bone tumors. The main type of lung tumor in both dog and rat is the bronchioloalveolar carcinoma (adenocarcinoma). However, tumor type is a function of radiation dose and dose-distribution at high doses. Bone ranks next to lung as the tissue developing the most tumors following inhalation of transuranics

  4. Deposition, translocation, and effects of transuranic particles inhaled by experimental animals

    International Nuclear Information System (INIS)

    Craig, D.K.; Ballou, J.E.; Dagle, G.E.; Mahlum, D.D.; Park, J.F.; Sanders, C.L.; Sikov, M.R.; Stuart, B.O.

    1977-01-01

    Inhalation exposure constitutes the most likely route of entrance for transuranics into the body. Cancer is the most likely consequence of exposure, but several thousand workers have been exposed during the last 30 yrs without, so far, evidence of exposure-related effects. Several soluble and insoluble transuranic compounds have been studied in rodents and dogs, either alone or combined with exposure to other materials (e.g., PuO 2 --UO 2 fuel and Na). These studies have provided a wide variety of spatial and temporal dose distribution patterns in the lung. The distribution and total initial deposition in the respiratory tract is a function of the physical characteristics of the inhaled aerosols (size distribution, shape, hygroscopicity) and of the morphology and physiology of the animal. Translocation rates, organ and tissue distribution and excretion in urine and feces, are a function of the physicochemical characteristics of the deposited material (solubility, specific activity, chemical compound, etc.). Differences in rate of translocation of the solubilized material, primarily to the liver and bone, determines the radiation dose to the various tissues involved. Insoluble particles of plutonium dioxide are transferred to the thoracic lymph nodes, which may be functionally destroyed as a consequence. Radiation pneumonitis and pulmonary fibrosis are the main causes of death in animals with cumulative radiation doses to the lung of a few thousand rads. The most significant long-term effect of inhaled transuranic compounds in animals is the development of lung and bone tumors. The main type of lung tumor in both dog and rat is the bronchioloalveolar carcinoma (adenocarcinoma). However, tumor type is a function of radiation dose and dose-distribution at high doses. Bone ranks next to lung as the tissue developing the most tumors following inhalation of transuranics

  5. Conservation of Mechanical and Electric Energy: Simple Experimental Verification

    Science.gov (United States)

    Ponikvar, D.; Planinsic, G.

    2009-01-01

    Two similar experiments on conservation of energy and transformation of mechanical into electrical energy are presented. Both can be used in classes, as they offer numerous possibilities for discussion with students and are simple to perform. Results are presented and are precise within 20% for the version of the experiment where measured values…

  6. Anorexia in human and experimental animal models: physiological aspects related to neuropeptides.

    Science.gov (United States)

    Yoshimura, Mitsuhiro; Uezono, Yasuhito; Ueta, Yoichi

    2015-09-01

    Anorexia, a loss of appetite for food, can be caused by various physiological and pathophysiological conditions. In this review, firstly, clinical aspects of anorexia nervosa are summarized in brief. Secondly, hypothalamic neuropeptides responsible for feeding regulation in each hypothalamic nucleus are discussed. Finally, three different types of anorexigenic animal models; dehydration-induced anorexia, cisplatin-induced anorexia and cancer anorexia-cachexia, are introduced. In conclusion, hypothalamic neuropeptides may give us novel insight to understand and find effective therapeutics strategy essential for various kinds of anorexia.

  7. Spectroscopic characterization of bone tissue of experimental animals after glucocorticoid treatment and recovery period

    Science.gov (United States)

    Mitić, Žarko J.; Najman, Stevo J.; Cakić, Milorad D.; Ajduković, Zorica R.; Ignjatović, Nenad L.; Nikolić, Ružica S.; Nikolić, Goran M.; Stojanović, Sanja T.; Vukelić, Marija Đ.; Trajanović, Miroslav D.

    2014-09-01

    The influence of glucocorticoids on the composition and mineral/organic content of the mandible in tested animals after recovery and healing phase was investigated in this work. The results of FTIR analysis demonstrated that bone tissue composition was changed after glucocorticoid treatment. The increase of calcium, magnesium, phosphorus content and mineral part of bones was statistically significant in recovery phase and in treatment phase that included calcitonin and thymus extract. Some changes also happened in the organic part of the matrix, as indicated by intensity changes for already present IR bands and the appearance of new IR bands in the region 3500-1300 cm-1.

  8. Evaluation of experimental animal biological state at exposure to low-dose ionizing radiation

    International Nuclear Information System (INIS)

    Rozanov, V.A.; Rejtarova, T.Je.; Chernyikov, G.B.; Timoshevs'ka, Je.V.; Kozozojeva, O.O.

    1997-01-01

    New approaches to quantitative evaluation of ionizing radiation absorbed dose within the low-dose range (up to 400 mGy) according to the degree of the organism biological response was developed. The purpose of the stage of the work published in Communication 1 is to evaluate the shifts in the animal behaviour and cellular composition of the blood at irradiation by the dose of 100,200 and 400 mGy. Distinct dose dependence of behaviour reactions and hematological indices within the dose range of 100-400 mGy was not noted

  9. Time-dependent cytokine expression in bone of experimental animals after hydroxyapatite (Hap) implantation

    International Nuclear Information System (INIS)

    Pilmane, M; Salms, G; Salma, I; Skagers, A; Locs, J; Loca, D; Berzina-Cimdina, L

    2011-01-01

    Proinflammatory cytokines mediate bone loss around the implants in patients with peri-implant disease. However, there is no complete data about the expression of cytokines into the bone around the implants. The aim of this work was to investigate the distribution and appearance of inflammatory cytokines and anti-inflammatory proteins in the bone of jaw of experimental rabbits in different time periods after HAp implantation. Material was obtained from 8 rabbits in lower jaw 6 and 8 months after HAp implants were placed. Tissues were processed for immunohistochemical detection of tumor necrosis factor alfa (TNFα), Interleukin 1, 6, 8, 10 (IL-1, IL-6, IL-8, IL-10) and defensin 2. Results demonstrated practically unchanged expression of IL-6 and IL-10 between both - experimental and control side 6 months after implantation, while IL-1 and IL-8 notably increased in control side. IL-1 and IL-10 expression did not change in either the experimental side nor the controle side after 8 months HAP implantation, but IL-6 and IL-8 demonstrated a decrease in the control sites. Only IL-8 was elevated with time in experimental sites, while IL-10 showed individual variations in 2 cases.

  10. Time-dependent cytokine expression in bone of experimental animals after hydroxyapatite (Hap) implantation

    Energy Technology Data Exchange (ETDEWEB)

    Pilmane, M [Riga Stradins University, Institute of Anatomy and Anthropology, Dzirciema 16, LV-1007, Riga (Latvia); Salms, G; Salma, I; Skagers, A [Riga Stradins University, Department of Oral and Maxillofacial Surgery, Dzirciema 20. LV-1007, Riga (Latvia); Locs, J; Loca, D; Berzina-Cimdina, L, E-mail: pilmane@latnet.lv [Riga Technical University, Riga Biomaterials innovation and development centre, Pulka 3/3, LV-1007, Riga (Latvia)

    2011-06-23

    Proinflammatory cytokines mediate bone loss around the implants in patients with peri-implant disease. However, there is no complete data about the expression of cytokines into the bone around the implants. The aim of this work was to investigate the distribution and appearance of inflammatory cytokines and anti-inflammatory proteins in the bone of jaw of experimental rabbits in different time periods after HAp implantation. Material was obtained from 8 rabbits in lower jaw 6 and 8 months after HAp implants were placed. Tissues were processed for immunohistochemical detection of tumor necrosis factor alfa (TNF{alpha}), Interleukin 1, 6, 8, 10 (IL-1, IL-6, IL-8, IL-10) and defensin 2. Results demonstrated practically unchanged expression of IL-6 and IL-10 between both - experimental and control side 6 months after implantation, while IL-1 and IL-8 notably increased in control side. IL-1 and IL-10 expression did not change in either the experimental side nor the controle side after 8 months HAP implantation, but IL-6 and IL-8 demonstrated a decrease in the control sites. Only IL-8 was elevated with time in experimental sites, while IL-10 showed individual variations in 2 cases.

  11. Modular Organization of Mechanisms of Achromatic Vision in Human and Animals

    Directory of Open Access Journals (Sweden)

    Aleksander M. Chernorizov

    2011-01-01

    Full Text Available Psychophysiological research into achromatic vision in humans and vertebrates displays that light intensity is coded by a two-dimensional "excitation vector". The components of that vector are responses of brightness and darkness neurons (or, according to another classification, on- and o/f-neurons. It means that a current sensation of brightness is determined by a corresponding interrelation between activities of those two systems responding in opponent way to set. The present research is devoted to testing of a hypothesis asserting that two-module organization of achromatic vision is a universal principle of brightness coding in a wide raw of animals including invertebrates. The paper represents certain results of registration and analysis of electroretinogram and total activity of the optical nerve in snail Helix lucorum to diffuse light flashes of different intensities. The obtained experimental data, along with the already existing reference data, allow us to assume that on- and off-systems may constitute the neural basis for brightness coding in the invertebrates. The peculiarity of on- and o/f-systems in vertebrates is that they are formed already at the photoreceptor level.

  12. Evaluation of the effect of conventionally prepared swarna makshika bhasma on different bio-chemical parameters in experimental animals

    Directory of Open Access Journals (Sweden)

    Sudhaldev Mohapatra

    2011-01-01

    Full Text Available Swarna makshika (chalcopyrite bhasma (SMB has been used for different therapeutic purposes since long in Ayurveda. The present study is conducted to evaluate the effect of conventionally prepared SMB on different bio-chemical parameters in experimental animals, for providing scientific data base for its logical use in clinical practice. The genuine SMB was prepared by following classical techniques of shodhana and marana most commonly used by different Ayurvedic drug manufacturers. Shodhana was done by roasting raw swarna makshika with lemon juice for three days and marana was performed by 11 putas . The experimental animals (rats were divided into two groups. SMB mixed with diluted honey was administered orally in therapeutic dose to Group SMB and diluted honey only was administered to vehicle control Group, for 30 days. The blood samples were collected twice, after 15 days and after 30 days of drug administration and different biochemical investigations were done. Biochemical parameters were chosen based on references from Ayurvedic classics and contemporary medicine. It was observed that Hb% was found significantly increased and LDL and VLDL were found significantly decreased in Group SMB when compared with vehicle control group. This experimental data will help the clinician for the logical use of SMB in different disease conditions with findings like low Hb% and high LDL, VLDL levels.

  13. Domestic Pig (Sus scrofa) as an Animal Model for Experimental Trypanosoma cruzi Infection

    Science.gov (United States)

    Yauri, Verónica; Castro-Sesquen, Yagahira E.; Verastegui, Manuela; Angulo, Noelia; Recuenco, Fernando; Cabello, Ines; Malaga, Edith; Bern, Caryn; Gavidia, Cesar M.; Gilman, Robert H.

    2016-01-01

    Pigs were infected with a Bolivian strain of Trypanosoma cruzi (genotype I) and evaluated up to 150 days postinoculation (dpi) to determine the use of pigs as an animal model of Chagas disease. Parasitemia was observed in the infected pigs during the acute phase (15–40 dpi). Anti-T.cruzi immunoglobulin M was detected during 15–75 dpi; high levels of anti-T.cruzi immunoglobulin G were detected in all infected pigs from 75 to 150 dpi. Parasitic DNA was observed by western blot (58%, 28/48) and polymerase chain reaction (27%, 13/48) in urine samples, and in the brain (75%, 3/4), spleen (50%, 2/4), and duodenum (25%, 1/4), but no parasitic DNA was found in the heart, colon, and kidney. Parasites were not observed microscopically in tissues samples, but mild inflammation, vasculitis, and congestion was observed in heart, brain, kidney, and spleen. This pig model was useful for the standardization of the urine test because of the higher volume that can be obtained as compared with other small animal models. However, further experiments are required to observe pathological changes characteristic of Chagas disease in humans. PMID:26928841

  14. Effect of intraoperative PEEP application on colonic anastomoses healing: An experimental animal study.

    Science.gov (United States)

    Turkoglu, Mehmet; Bostancı, Erdal Birol; Bilgili, Hasan; Türkoğlu, Yıldız; Karadeniz, Ümit; Aydoğ, Gülden; Erçin, Uğur; Bilgihan, Ayşe; Özer, İlter; Akoğlu, Musa

    2015-07-27

    This study aimed to assess the effect of intraoperative PEEP intervention on the healing of colonic anastomoses in rabbits. Thirty-two New Zealand type male rabbits were divided into two groups of sixteen animals each. Following ventilation with tracheostomy, colonic resection and anastomosis were performed in both groups. While 10 cm H2O PEEP level was applied in Group I (PEEP), Group II (ZEEP) was ventilated without PEEP throughout the surgery. Half of the both PEEP and ZEEP group animals were killed on the third postoperative day, while the remaining half on the seventh. Anastomotic bursting pressures, the tissue concentrations in hydroxyproline, and histological assessments were performed. Besides, intraoperative oxygen saturation and postoperative arterial blood gas parameters were also compared. On the first postoperative day, both arterial oxygen tension (PO2) and oxygen saturation (SO2) in the PEEP group were significantly higher than in the ZEEP group. On the seventh postoperative day, the bursting pressures of the anastomoses were significantly higher in the PEEP group, however the hydroxyproline content was significantly lower in the PEEP group than that in the ZEEP group. At day 7, PEEP group was significantly associated with increased neoangiogenesis compared with the ZEEP group. The anastomotic healing process is positively influenced by the intraoperative PEEP application.

  15. Anti-inflammatory and antinociceptive activities A of eugenol essential oil in experimental animal models

    Directory of Open Access Journals (Sweden)

    Apparecido N. Daniel

    Full Text Available Eugenia caryophyllata, popular name "clove", is grown naturally in Indonesia and cultivated in many parts of the world, including Brazil. Clove is used in cooking, food processing, pharmacy; perfumery, cosmetics and the clove oil (eugenol have been used in folk medicine for manifold conditions include use in dental care, as an antiseptic and analgesic. The objective of this study was evaluated the anti-inflammatory and antinociceptive activity of eugenol used for dentistry purposes following oral administration in animal models in vivo. The anti-inflammatory activity of eugenol was evaluated by inflammatory exudates volume and leukocytes migration in carrageenan-induced pleurisy and carrageenan-induced paw edema tests in rats. The antinociceptive activity was evaluated using the acetic acid-induced writhing and hot-plate tests in mice. Eugenol (200 and 400 mg/kg reduced the volume of pleural exudates without changing the total blood leukocyte counts. At dose of 200 mg/kg, eugenol significantly inhibited carrageenan-induced edema, 2-4 h after injection of the flogistic agent. In the hot-plate test, eugenol administration (100 mg/kg showed unremarkable activity against the time-to-discomfort reaction, recorded as response latency, which is blocked by meperidine. Eugenol at doses of 50, 75 and 100 mg/kg had a significant antinociceptive effect in the test of acetic-acid-induced abdominal writhing, compared to the control animals. The data suggest that eugenol possesses anti-inflammatory and peripheral antinociceptive activities.

  16. Effect of the timing of tourniquet release on postoperative hematoma formation: an experimental animal study

    Energy Technology Data Exchange (ETDEWEB)

    Himel, H.N.; Ahmad, M.; Parmett, S.R.; Strauss, H.W.; May, J.W. Jr.

    1989-04-01

    There is a controversy over when to release a pneumatic tourniquet after completing a hand surgical procedure. To study this controversy, we performed a standardized operation with tourniquet inflow occlusion on both lower legs of a series of rabbits. Total tourniquet time and the procedure performed, including intraoperative Bovie electrocautery of actual and potential bleeding points identified with 2.5 X loupe magnification, were identical on the two sides, except for the method of tourniquet release. On one leg, the tourniquet was released and all new bleeding points were controlled prior to wound closure. On the other leg, the tourniquet was released after the wound had been closed and dressed. Animals were injected with technetium-99m-labeled red blood cells and scanned to measure hematoma formation. Qualitatively, we observed more label in the leg whose tourniquet was released after wound closure in 17 of the 20 animals (p less than 0.005). Quantitatively, we also measured more mean label in the leg whose tourniquet was released after the wound was closed (p less than 0.001). Tourniquet release after wound closure was associated with greater hematoma formation.

  17. Effect of the timing of tourniquet release on postoperative hematoma formation: an experimental animal study

    International Nuclear Information System (INIS)

    Himel, H.N.; Ahmad, M.; Parmett, S.R.; Strauss, H.W.; May, J.W. Jr.

    1989-01-01

    There is a controversy over when to release a pneumatic tourniquet after completing a hand surgical procedure. To study this controversy, we performed a standardized operation with tourniquet inflow occlusion on both lower legs of a series of rabbits. Total tourniquet time and the procedure performed, including intraoperative Bovie electrocautery of actual and potential bleeding points identified with 2.5 X loupe magnification, were identical on the two sides, except for the method of tourniquet release. On one leg, the tourniquet was released and all new bleeding points were controlled prior to wound closure. On the other leg, the tourniquet was released after the wound had been closed and dressed. Animals were injected with technetium-99m-labeled red blood cells and scanned to measure hematoma formation. Qualitatively, we observed more label in the leg whose tourniquet was released after wound closure in 17 of the 20 animals (p less than 0.005). Quantitatively, we also measured more mean label in the leg whose tourniquet was released after the wound was closed (p less than 0.001). Tourniquet release after wound closure was associated with greater hematoma formation

  18. Experimental evaluation of mechanical properties of softwood using acoustic methods

    Czech Academy of Sciences Publication Activity Database

    Tippner, J.; Hrivnák, J.; Kloiber, Michal

    2016-01-01

    Roč. 11, č. 1 (2016), s. 503-518 ISSN 1930-2126 R&D Projects: GA MK(CZ) DF11P01OVV001 Keywords : non destructive testing * Norway spruce * Scots pine * Silver fir * sound speed * strength * stress wave Subject RIV: AL - Art, Architecture, Cultural Heritage Impact factor: 1.321, year: 2016 http://ojs.cnr.ncsu.edu/index.php/BioRes/article/view/BioRes_11_1_503_Tippner_Mechanical_Properties_Acoustic_Methods/4018

  19. Evaluation of analgesic and anti-inflammatory activity of a combination of tramadol-ibuprofen in experimental animals.

    Science.gov (United States)

    Suthakaran, Chidambarann; Kayalvizhi, Muniyagounder K; Nithya, Karnam; Raja, Thozhudalangudy Ar

    2017-01-01

    Pain is the major concern of patients attending dental clinics, and satisfactory pain relief has always been difficult to achieve. Since the pathophysiology of pain is a complex, central and peripheral nervous system process, combined analgesic regimens with different mechanisms of action as a multimodal approach are becoming popular among the clinicians and dentists. The aim of the present study was to evaluate the analgesic and anti-inflammatory activity of ibuprofen and tramadol when used alone or in combination in animal models of pain and inflammation. The animals were divided into six groups with six animals in each group. Analgesic activity was assessed by hot plate method in rats and by acetic acid-induced writhing test in mice. Paw edema model in rats after induction with 0.1 mL of 1% carrageenan was used to assess the anti-inflammatory activity. Analysis of variance followed by Tukey's honestly significant difference post hoc test was used for statistical analysis. Combined use of tramadol and ibuprofen provided enhanced analgesic and anti-inflammatory effects in animal models of pain and inflammation.

  20. Kinetics of sup(99m)Tc-EHDP administered by intramuscular injection in man and in experimental animals

    Energy Technology Data Exchange (ETDEWEB)

    Vattimo, A.; Lore, F.; Pisani, M.

    1981-06-01

    With the aim of assessing the kinetics of a diphosphonate administered by intramuscular injection, we have studied the behaviour of sup(99m)Tc-labelled 1-hydroxy-1, 1-diphosphonate in man and in experimental animals, after intramuscular injection. The curves of plasma and urine radioactivity were analyzed in a six-compartment kinetic model containing seven transition coefficients. The results show that the diphosphonate given by intramuscular injection is absorbed rapidly and completely. Therefore the possibility of using this way of administration should be considered in the pathological conditions in which diphosphonates are used as therapeutic agents.

  1. Variability of the dose effect in the radio-biologic experimentation on animals

    International Nuclear Information System (INIS)

    Peters, R.; Sailer, U.; Peters, K.

    1981-01-01

    As already demonstrated for Wistar rats, the radioresistance of Siv-50 male and female rats increases continually during their first months of life. Furthermore, males show a higher radioresistance than females during this period. The authors show with the same animals that a very radiosensitive rat strain can become a highly radioresistant strain after 2 1/2 years. After whole-body irradiation with 800-900 R, the increase of resistance of 85 days old males was between 62% and 68%. As a cause of this resistance increase, a mixed infection with Bordetella bronchiseptica and other germs is discussed. On the basis of literature, the authors discuss the occurrence of radioresistance increases after immunization or preconditioning with various bacterial vaccines and bacterial endotoxins. (orig.) [de

  2. Consequences of the exposure at low dose rates-contribution of animal experimentation

    International Nuclear Information System (INIS)

    Masse, R.

    1990-01-01

    The exposure of laboratory animals to the various types of radiations will induce cancers in relation with the tissue absorbed doses. The shape of the dose-effet relationship is most variable. It is important to distinguish which tumours are comparable to human tumours. Those showing more analogies answer but seldom to the classical lineo-quadratic relationship; however, a strong attenuation of induction is demonstrated at low dose rates. Quasi-threshold relationships are seen after the exposure of some tissues to high-LET radiations. These observations question the validity of generalizing the radiobiologists' dual action theory, setting the origin of the dose-effect relationship in the induction of events within the DNA molecule. There is an alternative in the cellular collaboration events; it assumes that the effectiveness per dose unit decreases constantly as an inverse function of the dose rate [fr

  3. Histopathological changes in the kidney of experimental animals caused by lethal doses of thallium

    Energy Technology Data Exchange (ETDEWEB)

    Danilewicz, M; Danilewicz, M; Kurnatowski, A

    1979-01-01

    The experiment was carried out on 65 white male Wistar rats and 65 white male Swiss mice poisoned with thallium sulfate in doses 30 to 40 mg/kg body weight. The animals were sacrificed in the 4, 8, 24, 48th hours of experiment and their kidneys were submitted to light and an electron microscopic examination. With the light microscope necrosis of epithelium of Henle loops, hydropic degeneration, swelling and focal necrosis of epithelium of proximal convoluted tubules, and stromal oedema were seen. An electron microscopic study pointed out swelling and degenerative changes in the mitochondria, loss of microvilli in many cells, dilatation of endoplasmic reticulum and decrease of electron density of basement membranes. Urea level in blood serum and protein level in urine increased.

  4. A new mechanism of macrophyte mitigation: how submerged plants reduce malathion's acute toxicity to aquatic animals.

    Science.gov (United States)

    Brogan, William R; Relyea, Rick A

    2014-08-01

    A growing body of evidence suggests that aquatic plants can mitigate the toxicity of insecticides to sensitive aquatic animals. The current paradigm is that this ability is driven primarily by insecticide sorption to plant tissues, especially for hydrophobic compounds. However, recent work shows that submerged plants can strongly mitigate the toxicity of the relatively hydrophilic insecticide malathion, despite the fact that this compound exhibits a slow sorption rate to plants. To examine this disparity, we tested the hypothesis that the mitigating effect of submerged plants on malathion's toxicity is driven primarily by the increased water pH from plant photosynthesis causing the hydrolysis of malathion, rather than by sorption. To do this, we compared zooplankton (Daphnia magna) survival across five environmentally relevant malathion concentrations (0, 1, 4, 6, or 36 μg L(-1)) in test containers where we chemically manipulated water pH in the absence of plants or added the submerged plant (Elodea canadensis) but manipulated plant photosynthetic activity via shading or no shading. We discovered that malathion was equally lethal to Daphnia at all concentrations tested when photosynthetically inactive (i.e. shaded) plants were present (pH at time of dosing=7.8) or when pH was chemically decreased (pH=7.7). In contrast, when photosynthetically active (i.e. unshaded) plants were present (pH=9.8) or when pH was chemically increased (pH=9.5), the effects of 4 and 6 μg L(-1) of malathion on Daphnia were mitigated strongly and to an equal degree. These results demonstrate that the mitigating effect of submerged plants on malathion's toxicity can be explained entirely by a mechanism of photosynthesizing plants causing an increase in water pH, resulting in rapid malathion hydrolysis. Our findings suggest that current ecotoxicological models and phytoremediation strategies may be overlooking a critical mechanism for mitigating pesticides. Copyright © 2014 Elsevier Ltd

  5. Evaluation of agents to detect inflammatory foci using an experimental animal model

    International Nuclear Information System (INIS)

    Shimpi, H.H.; Noronha, O.P.D.; Samuel, A.M.

    1997-01-01

    We have evaluated the propensities of four agents- two metal complexes and two protein species, viz. 67 Ga-citrate, 99m Tc-citrate, 99m Tc-human immunoglobulin ( 99m Tc-HIG); and 99m Tc-human serum albumin ( 99m Tc-HSA), for localization of (turpentine- induced) inflammatory lesions in a rat and rabbit animal model systems. All these radiopharmaceuticals showed fairly good uptake in inflammatory lesions. 99m Tc-HIG, 99m Tc-HSA and 67 Ga-citrate showed slower blood clearance and higher liver uptakes. On the other hand 99m Tc-citrate demonstrated faster blood clearance and negligible liver and gut accumulation. The respective inflamed/normal muscle (IM/NM) ratios obtained with these agents in this animal model were in the following order: 99m Tc-HIG> 99m Tc-HSA> 67 Ga-citrate> 99m Tc-citrate at 5 h post injection. Although the IM/NM was relatively low in the case of 99m Tc-citrate as compared with other radiopharmaceuticals the inflammation could be detected within 1-3 h. post injection because of the higher activities that could be injected with this radiopharmaceutical. Since 99m Tc-citrate is predominantly excreted via renal pathway it is rapidly cleared from blood and shows fairly good accumulation in infection/inflammatory lesions at early time periods along with low uptakes in liver and adjacent organs. This agent can therefore be beneficially used to detect the abdominal abscess(es)/inflammation(s) within 1-3 h post injection. Because of its favourable characteristics, physical, biological, clinical, and even cost-effectiveness, it is suggested that 99m Tc-citrate could be tried out as an agent for detection of inflammation including abdominal and vertebral abscess(es). (author)

  6. Experimental evaluation of air distribution in mechanically ventilated residential rooms

    DEFF Research Database (Denmark)

    Tomasi, R.; Krajčík, M.; Simone, A.

    2013-01-01

    The effect of low ventilation rates (1 or 0.5 air change per hour) on thermal comfort and ventilation effectiveness was experimentally studied in a simulated residential room equipped with radiant floor heating/cooling and mixing ventilation systems. The tests were performed for various positions...... of supply and extract air terminals and different winter and summer boundary conditions. Vertical air temperature, operative temperature and air velocity profiles were measured in different positions in the room, and equivalent temperatures were derived, in order to characterize thermal comfort. Contaminant...... with unconditioned outdoor air supply, i.e. at the supply air temperatures higher than the room air temperature. Moreover, low floor temperatures were needed to maintain the desired reference temperature in the stratified thermal environment. Mainly in cooling conditions the ventilation effectiveness depended...

  7. Mechanical behavior of nanotwinned materials – experimental and computational approaches

    Energy Technology Data Exchange (ETDEWEB)

    Yavas, Hakan [Iowa State Univ., Ames, IA (United States)

    2016-12-17

    Nanotwinned materials exhibit high strength combined with excellent thermal stability, making them potentially attractive for numerous applications. When deposited on cold substrates at high rates, for example, silver films can be prepared with a high-density of growth twins with an average twin boundary spacing of less than 10 nm. These films show a very strong {111} texture, with the twin boundaries being perpendicular to the growth direction. The origins of superior mechanical and thermal properties of nanotwinned materials, however, are not yet fully understood and need further improvements.

  8. Signaling in a polluted world: oxidative stress as an overlooked mechanism linking contaminants to animal communication

    Directory of Open Access Journals (Sweden)

    Valeria Marasco

    2016-08-01

    Full Text Available The capacity to communicate effectively with other individuals plays a critical role in the daily life of an individual and can have important fitness consequences. Animals rely on a number of visual and non-visual signals, whose production brings costs to the individual. The theory of honest signaling states that these costs are higher for low than for high-quality individuals, which prevents cheating and makes signals, such as skin and plumage colouration, indicators of individual’s quality or condition. The condition-dependent nature of signals makes them ideally suited as indicators of environmental quality, implying that signal production might be affected by contaminants. In this mini-review article, we have made the point that oxidative stress (OS is one overlooked mechanism linking exposure to contaminants to signaling because (i many contaminants can influence the individual’s oxidative balance, and (ii generation of both visual and non-visual signals is sensitive to oxidative stress. To this end, we have provided the first comprehensive review on the way both non-organic (heavy metals, especially mercury and organic (persistent organic pollutants contaminants may influence either OS or sexual signaling. We have also paid special attention to emerging classes of pollutants like brominated flame-retardants and perfluoroalkoxy alkanes in order to stimulate research in this area. We have finally provided suggestions and warnings for future work on the links among OS, sexual signaling and contaminant exposure.

  9. Laser irradiation effects and its possible mechanisms of action on spermatozoa functions in domestic animals

    Directory of Open Access Journals (Sweden)

    S A Lone

    2017-01-01

    Full Text Available This article presents a review pertains the laser irradiation effects and its possible mechanisms of action on spermatozoa functions in domestic animals. To improve artificial insemination, laser is sensitive and cost effective technique, when compared to other conventional methods. Laser may have both positive and negative effects on spermatozoa functions. Since the effects of light are mediated by reactive oxygen species, and the levels of these reactive oxygen species following irradiating spermatozoa with laser may be responsible for determining the effects of laser on sperm. Dose of laser may be regarded as of great significance and this dosage of laser may be responsible for determining its effects on spermatozoa. Optimum dosage of laser for improving seminal attributes may vary among various species and this need to be standardized in each of them. The beneficial effects include improving sperm livability, acrosomal integrity, hypo-osmotic swelling response, mitochondrial function and computer-aided sperm analysis parameters. The increase in cytochrome c oxidase activity, ATP levels and mitochondrial membrane potential, in laser irradiated cells may be responsible for enhanced sperm quality parameters. Improving fertility with laser irradiated spermatozoa has been reported in few species like boar and need to be elaborated in other species. In conclusion laser may be regarded as an easy, cheap and time saving technology for improving artificial insemination; in addition, laser may have various potential applications in the field of reproductive biotechnology as well as in livestock farms and veterinary polyclinics.

  10. An experimental investigation on mechanical behaviour of eco - friendly concrete

    Science.gov (United States)

    Narender Reddy, A.; Meena, T.

    2017-11-01

    Fly ash (FA) and Alccofine are the eco-friendly materials that can be used in the production of concrete composites. Initially, concrete mixes of M30 grade with replacement of cement by 0%, 5%, 10%, 15%, 20% and 25% by weight of Fly ash were prepared. They were subjected to compression test so as to select the optimum replacement percentage of FA. Keeping this optimum percentage of FA as constant, additional replacement of cement with Alccofine was done varying its replacement in the range of 8%, 10%, 12% and 14%. The mechanical properties such as compressive, split tensile and flexural strengths of these mixes were computed for 7, 14 and 28 days. The results of Eco-Friendly Concrete (EFC) are compared with those of control concrete. It was observed that EFC mixes exhibited superior qualities like quick setting and enhanced workability, their mechanical properties were found to be higher than that of the conventional concrete. This goes to prove that the combination of FA and Alccofine together as replacement for cement would enhance the properties of EFC.

  11. An experimental study on the thermal valorization of municipal and animal wastes

    Energy Technology Data Exchange (ETDEWEB)

    Vamvuka, Despina; Sfakiotakis, Stelios [Department of Mineral Resources Engineering, Technical University of Crete, Crete (Greece); Panopoulos, Kyriakos D. [Centre for Research and Technology Hellas / Institute for Solid Fuels Technology and Applications (CERTH/ISFTA), 4th klm. Nat. Rd. Ptolemais-Kozani-P.O. box 95 – GR 50200 Ptolemais (Greece)

    2013-07-01

    Poultry wastes and refused derived fuel disposal through thermochemical processes, such as combustion, has been proposed. These fuels have calorific values that in many cases exceed 20MJ kg-1. An extensive analysis has been performed of pyrolysis and combustion results obtained by thermal analysis measurements. The weight loss data were recorded continuously, under dynamic conditions, in the range 25-1300 deg C. A first order parallel reactions model and a power low model fitted the experimental results accurately for pyrolysis and combustion, respectively. The pyrolysis of poultry waste was a complex process, occurring up to 1300 deg C with high activation energies.

  12. Morbillivirus Experimental Animal Models: Measles Virus Pathogenesis Insights from Canine Distemper Virus.

    Science.gov (United States)

    da Fontoura Budaszewski, Renata; von Messling, Veronika

    2016-10-11

    Morbilliviruses share considerable structural and functional similarities. Even though disease severity varies among the respective host species, the underlying pathogenesis and the clinical signs are comparable. Thus, insights gained with one morbillivirus often apply to the other members of the genus. Since the Canine distemper virus (CDV) causes severe and often lethal disease in dogs and ferrets, it is an attractive model to characterize morbillivirus pathogenesis mechanisms and to evaluate the efficacy of new prophylactic and therapeutic approaches. This review compares the cellular tropism, pathogenesis, mechanisms of persistence and immunosuppression of the Measles virus (MeV) and CDV. It then summarizes the contributions made by studies on the CDV in dogs and ferrets to our understanding of MeV pathogenesis and to vaccine and drugs development.

  13. A new system using NMR technology for measurement of body composition in experimental animals

    International Nuclear Information System (INIS)

    Suzuki, Jun; Nishikibe, Masaru

    2004-01-01

    Measurement of body composition (fat mass) is an important item in pathophysiological and pharmacological studies using small animals (mice) in the fields of obesity and diabetes. The existing methods are, however, difficult, time consuming, and require a shielding facility. Now a novel system using nuclear magnetic resonance (NMR) technique was developed for measurement of body composition in small animals (mice) that provides noninvasive and rapid measurement without anesthetics; we introduced and evaluated this system and tried another application of this system. First, we validated this system using canola oil, soft tissues (adipose and skeletal muscle), and various kinds of rodent chows. Accuracy, precision, and reproducibility of this system were demonstrated to be equal to those in standard chemical methods. A strong positive correlation (y=x) between the results of NMR and chemical methods was found. Secondly, we evaluated accuracy and assay range of the NMR method using live mice that were fasted overnight or fed high fat diet (HFD). In fasted mice, a small but quantitative decrease of fat mass (5.1% from 9.1%) was detected. Total decrease of fat and lean mass (5.0 g) in fasted mice was equivalent to the decrease of body weight (5.0 g). In mice fed the HFD, increase of fat mass with relative decrease of lean mass were qualitatively detected in a time-dependent manner. We would like to emphasize that operation of the system was actually easy and measurements were accomplished in a short time (1 minute). Thirdly, we tried to use the NMR system for determination of hepatic fat contents using mice fasted or treated with a peroxisome proliferator-activated receptor (PPAR)γ agonist; our results showed a quantitative increase in fat by fasting or in decrease in fat by the drug treatment. The changes of fat contents determined by the NMR method were well correlated with the changes in triglyceride and total cholesterol values obtained by the biochemical assays

  14. Experimental study of different carbon dust growth mechanisms

    International Nuclear Information System (INIS)

    Arnas, C.; Dominique, C.; Roubin, P.; Martin, C.; Laffon, C.; Parent, P.; Brosset, C.; Pegourie, B.

    2005-01-01

    Laboratory experiments are proposed to understand the growth mechanisms of spheroid carbon dust grains observed in Tokamaks with inside wall elements in graphite based materials. Different categories of solid grains in the nanometer size range are produced from graphite sputtering in rare gas plasmas. Dense primary particles are observed either individually or in the form of spherical agglomerates. The agglomeration process is likely to be stopped by Coulomb repulsion. Other particulates of higher size and cauliflower texture are formed by atomic-molecule accretion. Examples of these different cases are presented with specific characteristics provided by ex situ diagnostics. A comparison with dust samples collected in Tore Supra or observed in other Tokamaks is proposed

  15. [Modulation of scoliotic spine growth in experimental animals using intelligent metal bars].

    Science.gov (United States)

    Sánchez-Márquez, J M; Sánchez Pérez-Grueso, F J; Fernández-Baíllo, N; Gil-Garay, E; Antuña-Antuña, S

    2013-01-01

    To create an experimental structural scoliosis model in mice to evaluate the efficacy of shape-memory metals to gradually correct the deformity over time. Experimental scoliosis was generated in 3 week-old mice by means of a suture between the left scapula and pelvis for 8 weeks. They were then randomised into two groups: a control group, in which the suture was cut, and another, in those that also had a Nitinol straight memory-wire implant fixed to the column. Serial X-rays were performed to determine the efficacy of the Nitinol in the correction of the scoliosis. In a second time, the histological changes at apical vertical body level and the adjacent discs were evaluated pre- and post-correction. A mean 81.5° kyphoscoliosis was gradually induced. In the control group, after cutting the suture, an initial reduction in the deformity was observed, but later it remained stable throughout the time (54° at two weeks). In the Nitinol group, a gradual reduction was observed in the scoliosis angle value, to a mean of 8.7° at two weeks. The curvature of the apical vertebral body and adjacent discs were partially corrected after two weeks of correcting the deformity. This scoliosis model has demonstrated the efficacy of a straight Nitinol wire fixed to the spinal column in the gradual correction of kyphoscoliosis and in the changes in its adjacent structures. Copyright © 2013 SECOT. Published by Elsevier Espana. All rights reserved.

  16. Experimental and histological studies on appearance mechanism of ring enhancement

    International Nuclear Information System (INIS)

    Takasugi, Shinsuke; Kageyama, Takefumi; Yamashita, Shigeru; Kusaka, Kazumasa; Ueda, Shin

    1980-01-01

    Intracerebral hematoma was experimentally induced in 26 adult dogs of mixed breed by injecting autologous venous blood into the internal capsule of dogs. CT images and histological findings of these dogs with intracerebral hematoma were compared with time, and causes of changes in contrast enhancement (CE) CT images and CE positive images were discussed pathologically. It was thought that CE-CT positive images of intracerebral hematoma did not show special phenomena which occurred variously according to causes of hematoma, but general phenomena observed in the process of recovery of general intracerebral hematoma. Ring enhancement appeared mostly about 9 days after hematoma formation. There was a close relationship between appearance of ring enhancement and new vascularization which appeared in the process of recovery of hematoma. It was also thought that blood-brain barrier (B.B.B.) such as normal cerebral capillary vessels did not exist because new vascularization had the fine structure similar to muscle type capillary vessels. Ring enhancement might be seen probably because of the accumulation of contrast medium in regions where new vascularization without B.B.B. appeared. (Tsunoda, M.)

  17. Biological effects of daily inhalation of radon and its short-lived daughters in experimental animals

    International Nuclear Information System (INIS)

    Palmer, R.F.; Stuart, B.O.; Filipy, R.E.

    1973-01-01

    Syrian golden hamsters, C57BL mice, and specific-pathogen-free rats were exposed simultaneously in groups of 16 animals each for 90 hours per week to aerosols consisting of radon plus 3000--6000 Working Levels of radon-daughters with and without 18 mg/m 3 carnotite uranium ore dust. Condensation nuclei concentrations ranged from 2000--4000 per ml and from 90,000--120,000 per ml in the chamber without and with uranium ore dust, respectively. At 4 months of exposure only one of the rodents remained alive. Histopathology of radon-daughter exposed mice includes acute interstitial pneumonitis, severe pulmonary congestion, and supperative rhinitis; mice inhaling radon-daughters with ore showed these lesions plus macrophage proliferation, alveolar septal cell hyperplasia, and bronchial epithelial hyperplasia. Hamsters inhaling radon-daughters showed proliferating lesions characterized by alveolar septal thickening, bronchiolar epithelial hyperplasia, septal fibrosis, and occasionally adenomatoid metaplasia and squamous metaplasia. Hamsters inhaling radon-daughters with ore dust showed similar effects plus granulomatous response and intense septal fibrosis. Rats inhaling radon-daughters showed lesions similar to those of hamsters but more focalized with classic radiation pneumonitis; rats exposed to radon-daughters with ore showed similar lesions, with greater consolidation and pneumoconiosis. These findings will be discussed in relation to pulmonary pathology in uranium miners

  18. Experimental flow and perfusion measurement in an animal model with magnetic resonance tomography

    International Nuclear Information System (INIS)

    Schoenberg, S.O.; Bock, M.; Just, A.

    2001-01-01

    Aim. Validation of non-invasive methods for morphologic and functional imaging of the kidney under physiologic and pathophysiologic conditions. Material and Methods. In chronically instrumented animals (foxhounds) comparative measurements of renal flow and perfusion were performed. Magnetic resonance imaging techniques were compared to data obtained from implanted flow probes and total kidney weight post mortem. In the MR system, different degrees of renal artery stenosis could be induced by means of an implanted inflatable cuff. The degree of stenosis was verified with high-resolution 3D contrast-enhanced MR angiography (3D-CE-MRA) using an intravascular contrast agent. Results. The MR-data agreed well with the invasively obtained results. Artifacts resulting from the implanted flow probes and other devices could be kept to a minimum due to appropriate selection of the probe materials and measurement strategies. Stenoses could be reproduced reliably and quantified from the induced morphologic and functional changes. Conclusion. Morphologic and functional MR techniques are well suited for non-invasive in vivo assessment of renal blood flow physiology. (orig.) [de

  19. Experimental Animal Models of Pancreatic Carcinogenesis for Prevention Studies and Their Relevance to Human Disease

    Directory of Open Access Journals (Sweden)

    Hitoshi Nakagama

    2011-02-01

    Full Text Available Pancreatic cancer is difficult to cure, so its prevention is very important. For this purpose, animal model studies are necessary to develop effective methods. Injection of N-nitrosobis(2-oxopropylamine (BOP into Syrian golden hamsters is known to induce pancreatic ductal adenocarcinomas, the histology of which is similar to human tumors. Moreover, K-ras activation by point mutations and p16 inactivation by aberrant methylation of 5’ CpG islands or by homozygous deletions have been frequently observed in common in both the hamster and humans. Thus, this chemical carcinogenesis model has an advantage of histopathological and genetic similarity to human pancreatic cancer, and it is useful to study promotive and suppressive factors. Syrian golden hamsters are in a hyperlipidemic state even under normal dietary conditions, and a ligand of peroxizome proliferator-activated receptor gamma was found to improve the hyperlipidemia and suppress pancreatic carcinogenesis. Chronic inflammation is a known important risk factor, and selective inhibitors of inducible nitric oxide synthase and cyclooxygenase-2 also have protective effects against pancreatic cancer development. Anti-inflammatory and anti-hyperlipidemic agents can thus be considered candidate chemopreventive agents deserving more attention.

  20. Variability of the dose effect in the radio-biologic experimentation on animals

    International Nuclear Information System (INIS)

    Peters, R.; Sailer, U.; Peters, K.

    1981-01-01

    The radioresistance of Wistar males and females as well as of Siv-50 rat males increases more and more when they are between two and five months old. This increase of resistance is inversely proportional to the intensity of their growth. During this period of life, Wistar males show a practically linear increase of resistance while females have an exponential curve of resistance. There are differences in radiosensibility between the two sexes of one breed. a) Until the age of four months, the resistance of females is 50 to 60R below that of males of the same breed and the same age. b) About the age of five months, the sensibility values of Wistar males and females are approaching. It might be possible that females now develop a higher radioresistance than males. Studies of Crossfill, Kohn und Kallmann suggest a possible reversal of the situation of resistance between mouse males and females. Different breeds posses different radiosensibility thresholds. The Siv-50 rat which becomes bigger and grows more rapidly, shows a higher radiosensibility than Wistar rats of the same age. The development of radioresistance in mice and rats which is changing several times during the life of these animals is discussed in consideration of literature and the own results. The authors underline the scale of variation of the LD-50 values which comprises several 100R. The theory pretending that adult mice are more radioresistant than rats cannot be maintained any longer. (orig.) [de

  1. Studies on the fate of poisonous metals in experimental animal, (2)

    International Nuclear Information System (INIS)

    Omori, Yoshihito; Takanaka, Akira; Onoda, Kin-ichi; Nakaura, Shinsuke; Urakubo, Goro

    1975-01-01

    Three doses of cadmium chloride solutions (1, 5 and 10 mg/kg/day) were given orally and repeatedly to 3 groups of male rats (27--28 rats per 1 group) for 20 days. In 1 mg/kg group, depression of daily gain of body weight was observed to some extent after 13th day, and significant depression was noted earlier in 5 and 10 mg/kg groups. Decrease of daily food and water consumption was observed after 10--12th day, and mortality of each group until 21st day was 2/27, 8/27 and 9/28, respectively. At 21st day, solution of sup(115m)CdCl 2 (2μCi/mg CdCl 2 /2 ml/kg) was given orally to investigate the alternative distribution of this metal, dissecting the animals and measuring the radioactivities. Comparing with the control group, increase of adrenal weight, decrease of seminal vesicle weight, relaxation of gastrointestinal tract and increase of the contents of the tract were found in every pretreated group. Thicker distribution of sup(115m)Cd were seen in many organs and tissues, including blood, or every pretreated group compared with control group, however, the concentration in liver and bone was lower contrarily. Especially, the amount of remaining sup(115m)Cd in stomach was more in 1 and 5 mg/kg groups than the control group, and the fact suggested the delay of gastric emptying rate. (auth.)

  2. Dose and effect relationship of radiation induced cancer and its influencing factors in experimental animals, 1

    International Nuclear Information System (INIS)

    Sasaki, Shunsaku; Sato, Fumiaki; Eto, Hideo

    1975-01-01

    The data of risk evaluation of external irradiation were integrated with animal experiments from the aspects of qualitative generalizations of characteristics of radiation induced tumors. Studies covered competition of cause of death, figure of dose-to-effect relationship, characteristics of low dose rate of irradiation, relative biological effectiveness (RBE) of high LET radiation, effects of feactionated irradiation, complex actions with chemical substances, effects of protectional medium, differences of radiosensitivity by species and strains, and age dependency of sensitivities. Competition of cause of death by time length of latent period and degree of malignancy of the disease. Discussion on competition of death suggested the following idea: 1) incidence of tumor induction in the individual level did not correspond to transformation in the cellular level, and 2) relative incidence of tumor induction after a certain dose of whole body irradiation did not indicate the relative sensitivity of each tissue, for the relationship between tumor incidence and exposure dose was not a linear relationship. The dose-to-effect relationship of tumor induction was decided by following factors: i) sensitivity on transformation of cells, ii) sensitivity on the death of potential tumor cells, and iii) competition of the cause of death. Tumor induction by low dose rate irradiation was also studied by comparing qualitative and quantitative differences between high dose rate single irradiation and a series of low dose rate irradiation. (Serizawa, K.)

  3. Circuit Models and Experimental Noise Measurements of Micropipette Amplifiers for Extracellular Neural Recordings from Live Animals

    Directory of Open Access Journals (Sweden)

    Chang Hao Chen

    2014-01-01

    Full Text Available Glass micropipettes are widely used to record neural activity from single neurons or clusters of neurons extracellularly in live animals. However, to date, there has been no comprehensive study of noise in extracellular recordings with glass micropipettes. The purpose of this work was to assess various noise sources that affect extracellular recordings and to create model systems in which novel micropipette neural amplifier designs can be tested. An equivalent circuit of the glass micropipette and the noise model of this circuit, which accurately describe the various noise sources involved in extracellular recordings, have been developed. Measurement schemes using dead brain tissue as well as extracellular recordings from neurons in the inferior colliculus, an auditory brain nucleus of an anesthetized gerbil, were used to characterize noise performance and amplification efficacy of the proposed micropipette neural amplifier. According to our model, the major noise sources which influence the signal to noise ratio are the intrinsic noise of the neural amplifier and the thermal noise from distributed pipette resistance. These two types of noise were calculated and measured and were shown to be the dominating sources of background noise for in vivo experiments.

  4. Experimental Animal Models of Pancreatic Carcinogenesis for Prevention Studies and Their Relevance to Human Disease

    International Nuclear Information System (INIS)

    Takahashi, Mami; Hori, Mika; Mutoh, Michihiro; Wakabayashi, Keiji; Nakagama, Hitoshi

    2011-01-01

    Pancreatic cancer is difficult to cure, so its prevention is very important. For this purpose, animal model studies are necessary to develop effective methods. Injection of N-nitrosobis(2-oxopropyl)amine (BOP) into Syrian golden hamsters is known to induce pancreatic ductal adenocarcinomas, the histology of which is similar to human tumors. Moreover, K-ras activation by point mutations and p16 inactivation by aberrant methylation of 5′ CpG islands or by homozygous deletions have been frequently observed in common in both the hamster and humans. Thus, this chemical carcinogenesis model has an advantage of histopathological and genetic similarity to human pancreatic cancer, and it is useful to study promotive and suppressive factors. Syrian golden hamsters are in a hyperlipidemic state even under normal dietary conditions, and a ligand of peroxizome proliferator-activated receptor gamma was found to improve the hyperlipidemia and suppress pancreatic carcinogenesis. Chronic inflammation is a known important risk factor, and selective inhibitors of inducible nitric oxide synthase and cyclooxygenase-2 also have protective effects against pancreatic cancer development. Anti-inflammatory and anti-hyperlipidemic agents can thus be considered candidate chemopreventive agents deserving more attention

  5. A first vascularized skin equivalent as an alternative to animal experimentation.

    Science.gov (United States)

    Groeber, Florian; Engelhardt, Lisa; Lange, Julia; Kurdyn, Szymon; Schmid, Freia F; Rücker, Christoph; Mielke, Stephan; Walles, Heike; Hansmann, Jan

    2016-01-01

    Tissue-engineered skin equivalents mimic key aspects of the human skin, and can thus be employed as wound coverage for large skin defects or as in vitro test systems as an alternative to animal models. However, current skin equivalents lack a functional vasculature limiting clinical and research applications. This study demonstrates the generation of a vascularized skin equivalent with a perfused vascular network by combining a biological vascularized scaffold (BioVaSc) based on a decellularized segment of a porcine jejunum and a tailored bioreactor system. Briefly, the BioVaSc was seeded with human fibroblasts, keratinocytes, and human microvascular endothelial cells. After 14 days at the air-liquid interface, hematoxylin & eosin and immunohistological staining revealed a specific histological architecture representative of the human dermis and epidermis including a papillary-like architecture at the dermal-epidermal-junction. The formation of the skin barrier was measured non-destructively using impedance spectroscopy. Additionally, endothelial cells lined the walls of the formed vessels that could be perfused with a physiological volume flow. Due to the presence of a complex in-vivo-like vasculature, the here shown skin equivalent has the potential for skin grafting and represents a sophisticated in vitro model for dermatological research.

  6. Catheter visualisation in MR tomography: first animal experimental experiences with field inhomogeneity catheters

    International Nuclear Information System (INIS)

    Adam, G.; Glowinski, A.; Neuerburg, J.; Buecker, A.; Vaals, J.J. van; Hurtak, W.; Guenther, R.W.

    1997-01-01

    Purpose: To assess the feasibility of a new developed field inhomogeneity catheter for interventional MR imaging in vivo. Materials and methods: Three different prototypes of a field inhomogeneity catheter were investigated in 6 pigs. The catheters were introduced in Seldinger technique via the femoral vessels over a guide wire on an interventional MR system (Philips Gyroscan NT combined with a C-arm fluoroscopy unit [Philips BV 212[). Catheters were placed in veins and arteries. The catheter position was controlled by a fast gradient echo sequence (Turbo Field Echo [TEF[). Results: Catheters were introduced over a guide wire without complications in all cases. Using the field inhomogeneity concept, catheters were easily visualised in the inferior vena cava and the aorta by the fast gradient echo technique on MR in all cases. Although aortic branches were successfully cannulated, the catheters were not displayed by the TFE technique due to the complex and tortuous anatomy. All animals survived the experiments without complications. Conclusion: MR guided visualisation of a field inhomogeneity catheter is a simple concept which can be realised on each MR scanner and may allow intravascular MR guided interventions in future. (orig.) [de

  7. Experimental Animal Models of Pancreatic Carcinogenesis for Prevention Studies and Their Relevance to Human Disease

    Energy Technology Data Exchange (ETDEWEB)

    Takahashi, Mami, E-mail: mtakahas@ncc.go.jp; Hori, Mika; Mutoh, Michihiro [Division of Cancer Development System, Carcinogenesis Research Group, National Cancer Center Research Institute, 1-1, Tsukiji 5-chome, Chuo-ku, Tokyo 104-0045 (Japan); Wakabayashi, Keiji [Graduate School of Nutritional and Environmental Sciences, University of Shizuoka, Yada 52-1, Suruga-ku, Shizuoka 422-8526 (Japan); Nakagama, Hitoshi [Division of Cancer Development System, Carcinogenesis Research Group, National Cancer Center Research Institute, 1-1, Tsukiji 5-chome, Chuo-ku, Tokyo 104-0045 (Japan)

    2011-02-09

    Pancreatic cancer is difficult to cure, so its prevention is very important. For this purpose, animal model studies are necessary to develop effective methods. Injection of N-nitrosobis(2-oxopropyl)amine (BOP) into Syrian golden hamsters is known to induce pancreatic ductal adenocarcinomas, the histology of which is similar to human tumors. Moreover, K-ras activation by point mutations and p16 inactivation by aberrant methylation of 5′ CpG islands or by homozygous deletions have been frequently observed in common in both the hamster and humans. Thus, this chemical carcinogenesis model has an advantage of histopathological and genetic similarity to human pancreatic cancer, and it is useful to study promotive and suppressive factors. Syrian golden hamsters are in a hyperlipidemic state even under normal dietary conditions, and a ligand of peroxizome proliferator-activated receptor gamma was found to improve the hyperlipidemia and suppress pancreatic carcinogenesis. Chronic inflammation is a known important risk factor, and selective inhibitors of inducible nitric oxide synthase and cyclooxygenase-2 also have protective effects against pancreatic cancer development. Anti-inflammatory and anti-hyperlipidemic agents can thus be considered candidate chemopreventive agents deserving more attention.

  8. Hematological Changes Induced by Mercury Ions and Ionizing Radiation in Experimental Animals

    International Nuclear Information System (INIS)

    Kim, Jin-Kyu; Lee, Yun-Jong; Choi, Dae-Seong; Kim, Ji-Hyang; Cebulska-Wasilewska, Antonina

    2006-01-01

    Toxic metals such as lead, chromium, cadmium, mercury and arsenic are widely found in our environment. Humans are exposed to these metals from numerous sources, including contaminated air, water, soil and food. Mercury, one of the most diffused and hazardous organ specific environmental contaminants, exists in a wide variety of physical and chemical states, each of which has unique characteristics for a target organ specificity. Although reports indicate that mercury induces deleterious damage, little is known about its effects on living organisms. Ionizing radiation, an extensively used therapeutic modality in oncology, not only eradicates neoplastic cells but also generates inevitable side effects for normal tissues. Such biological effects are made through the production of reactive oxygen species which include a superoxide anion, a hydroxyl radical and a hydrogen peroxide. These reactive species may contribute to the radiation-induced cytotoxicity (e.g., chromosome aberrations, protein oxidation, and muscle injury) and to the metabolic and morphologic changes (e.g., increased muscle proteolysis and changes in the central nervous system) in animals and humans. In the present study, radioimmunoassay of the cortisol in the serum and the analysis of the hematological components and enzymes related to a tissue injury were carried out to evaluate the effects of mercury chloride in comparison with those of ionizing radiation

  9. Hematological Changes Induced by Mercury Ions and Ionizing Radiation in Experimental Animals

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Jin-Kyu; Lee, Yun-Jong; Choi, Dae-Seong [Korea Atomic Energy Research Institute, Taejon (Korea, Republic of); Kim, Ji-Hyang [Biotechnology Research Institute, Seoul (Korea, Republic of); Cebulska-Wasilewska, Antonina [The Henryk Niewodniczanski Institute of Nuclear Physics, Krakow (Poland)

    2006-07-01

    Toxic metals such as lead, chromium, cadmium, mercury and arsenic are widely found in our environment. Humans are exposed to these metals from numerous sources, including contaminated air, water, soil and food. Mercury, one of the most diffused and hazardous organ specific environmental contaminants, exists in a wide variety of physical and chemical states, each of which has unique characteristics for a target organ specificity. Although reports indicate that mercury induces deleterious damage, little is known about its effects on living organisms. Ionizing radiation, an extensively used therapeutic modality in oncology, not only eradicates neoplastic cells but also generates inevitable side effects for normal tissues. Such biological effects are made through the production of reactive oxygen species which include a superoxide anion, a hydroxyl radical and a hydrogen peroxide. These reactive species may contribute to the radiation-induced cytotoxicity (e.g., chromosome aberrations, protein oxidation, and muscle injury) and to the metabolic and morphologic changes (e.g., increased muscle proteolysis and changes in the central nervous system) in animals and humans. In the present study, radioimmunoassay of the cortisol in the serum and the analysis of the hematological components and enzymes related to a tissue injury were carried out to evaluate the effects of mercury chloride in comparison with those of ionizing radiation.

  10. Fourier Analysis: Graphical Animation and Analysis of Experimental Data with Excel

    Directory of Open Access Journals (Sweden)

    Margarida Oliveira

    2012-05-01

    Full Text Available According to Fourier formulation, any function that can be represented in a graph may be approximated by the “sum” of infinite sinusoidal functions (Fourier series, termed as “waves”.The adopted approach is accessible to students of the first years of university studies, in which the emphasis is put on the understanding of mathematical concepts through illustrative graphic representations, the students being encouraged to prepare animated Excel-based computational modules (VBA-Visual Basic for Applications.Reference is made to the part played by both trigonometric and complex representations of Fourier series in the concept of discrete Fourier transform. Its connection with the continuous Fourier transform is demonstrated and a brief mention is made of the generalization leading to Laplace transform.As application, the example presented refers to the analysis of vibrations measured on engineering structures: horizontal accelerations of a one-storey building deriving from environment noise. This example is integrated in the curriculum of the discipline “Matemática Aplicada à Engenharia Civil” (Mathematics Applied to Civil Engineering, lectured at ISEL (Instituto Superior de Engenharia de Lisboa. In this discipline, the students have the possibility of performing measurements using an accelerometer and a data acquisition system, which, when connected to a PC, make it possible to record the accelerations measured in a file format recognizable by Excel.

  11. Effect of x irradiation on the vascularization of experimental animal tumors

    Energy Technology Data Exchange (ETDEWEB)

    Saeki, Y; Ogawa, F; Nishiguchi, H; Tanaka, N; Murakami, K [Kyoto Prefectural Univ. of Medicine (Japan)

    1975-03-01

    The authors studied the effect of ionizing radiation on blood vessels and tumor growth in two animal tumor systems: a third generation isoplants of a mammary cancer and a spontaneously arising squamous cell carcinoma. Single cell suspensions were transplanted into a C3H and a C3Hf mouse respectively. They were irradiated once with 2000 rad when the tumors reached about 8 mm in diameter. Microangiography was performed at a constant temperature and pressure, and a contrast medium containing lead-oxide and gelatin was flushed the vena cava for 10 min. at 120 mmHg. Tumor shrinkage was followed by continuous regrowth. The basic vasculature of the mammary carcinoma consisted of abundant large and fine blood vessels corkscrewed or stretched from the periphery of the tumor to its center in complex reticular networks. One day after irradiation there were small scattered avascular areas which, by the third day formed a large central necrosis. Supervascularization was also observed, indicating that some hypoxic tumor cells could be reoxygenized. In 5 days vascularization was similar to that of a nonirradiated tumor. Conversely, The squamous cell carcinoma showed peripheral and central vascularization with abundant vascular and avascular areas and extravasion in the large avascular area. Two days after irradiation the vessels were dilated. At 3 days peripheral fine vessels were damaged but the central vasculature remained intact. Unlike the mammary carcinoma, supervascularization was not the typical finding. At 5 days, vascularization was similar to that of a nonirradiated tumor.

  12. Discrepant Results of Experimental Human Mesenchymal Stromal Cell Therapy after Myocardial Infarction: Are Animal Models Robust Enough?

    Directory of Open Access Journals (Sweden)

    Melina C den Haan

    Full Text Available Human mesenchymal stromal cells (MSCs have been reported to preserve cardiac function in myocardial infarction (MI models. Previously, we found a beneficial effect of intramyocardial injection of unstimulated human MSCs (uMSCs on cardiac function after permanent coronary artery ligation. In the present study we aimed to extend this research by investigating the effect of intramyocardial injection of human MSCs pre-stimulated with the pro-inflammatory cytokine interferon-gamma (iMSCs, since pro-inflammatory priming has shown additional salutary effects in multiple experimental disease models.MI was induced in NOD/Scid mice by permanent ligation of the left anterior descending coronary artery. Animals received intramyocardial injection of uMSCs, iMSCs or PBS. Sham-operated animals were used to determine baseline characteristics. Cardiac performance was assessed after 2 and 14 days using 7-Tesla magnetic resonance imaging and pressure-volume loop measurements. Histology and q-PCR were used to confirm MSC engraftment in the heart.Both uMSC and iMSC therapy had no significant beneficial effect on cardiac function or remodelling in contrast to our previous studies.Animal models for cardiac MSC therapy appear less robust than initially envisioned.

  13. Experimental task-based optimization of a four-camera variable-pinhole small-animal SPECT system

    Science.gov (United States)

    Hesterman, Jacob Y.; Kupinski, Matthew A.; Furenlid, Lars R.; Wilson, Donald W.

    2005-04-01

    We have previously utilized lumpy object models and simulated imaging systems in conjunction with the ideal observer to compute figures of merit for hardware optimization. In this paper, we describe the development of methods and phantoms necessary to validate or experimentally carry out these optimizations. Our study was conducted on a four-camera small-animal SPECT system that employs interchangeable pinhole plates to operate under a variety of pinhole configurations and magnifications (representing optimizable system parameters). We developed a small-animal phantom capable of producing random backgrounds for each image sequence. The task chosen for the study was the detection of a 2mm diameter sphere within the phantom-generated random background. A total of 138 projection images were used, half of which included the signal. As our observer, we employed the channelized Hotelling observer (CHO) with Laguerre-Gauss channels. The signal-to-noise (SNR) of this observer was used to compare different system configurations. Results indicate agreement between experimental and simulated data with higher detectability rates found for multiple-camera, multiple-pinhole, and high-magnification systems, although it was found that mixtures of magnifications often outperform systems employing a single magnification. This work will serve as a basis for future studies pertaining to system hardware optimization.

  14. An environmental friendly animal waste disposal process with ammonia recovery and energy production: Experimental study and economic analysis.

    Science.gov (United States)

    Shen, Ye; Tan, Michelle Ting Ting; Chong, Clive; Xiao, Wende; Wang, Chi-Hwa

    2017-10-01

    Animal manure waste is considered as an environmental challenge especially in farming areas mainly because of gaseous emission and water pollution. Among all the pollutants emitted from manure waste, ammonia is of greatest concern as it could contribute to formation of aerosols in the air and could hardly be controlled by traditional disposal methods like landfill or composting. On the other hand, manure waste is also a renewable source for energy production. In this work, an environmental friendly animal waste disposal process with combined ammonia recovery and energy production was proposed and investigated both experimentally and economically. Lab-scale feasibility study results showed that 70% of ammonia in the manure waste could be converted to struvite as fertilizer, while solid manure waste was successfully gasified in a 10kW downdraft fixed-bed gasifier producing syngas with the higher heating value of 4.9MJ/(Nm 3 ). Based on experimental results, economic study for the system was carried out using a cost-benefit analysis to investigate the financial feasibility based on a Singapore case study. In addition, for comparison, schemes of gasification without ammonia removal and incineration were also studied for manure waste disposal. The results showed that the proposed gasification-based manure waste treatment process integrated with ammonia recovery was most financially viable. Copyright © 2017 Elsevier Ltd. All rights reserved.

  15. Effects of experimental sleep deprivation on anxiety-like behavior in animal research: Systematic review and meta-analysis.

    Science.gov (United States)

    Pires, Gabriel Natan; Bezerra, Andréia Gomes; Tufik, Sergio; Andersen, Monica Levy

    2016-09-01

    Increased acute anxiety is a commonly reported behavioral consequence of sleep deprivation in humans. However, rodent studies conducted so far produced inconsistent results, failing to reproduce the same sleep deprivation induced-anxiety observed in clinical experiments. While some presented anxiogenesis as result of sleep deprivation, others reported anxiolysis. In face of such inconsistencies, this article explores the effects of experimental sleep deprivation on anxiety-like behavior in animal research through a systematic review and a series of meta-analyses. A total of 50 of articles met our inclusion criteria, 30 on mice, 19 on rats and one on Zebrafish. Our review shows that sleep deprivation induces a decrease in anxiety-like behavior in preclinical models, which is opposite to results observed in human settings. These results were corroborated in stratified analyses according to species, sleep deprivation method and anxiety measurement technique. In conclusion, the use of animal models for the evaluation of the relationship between sleep deprivation lacks translational applicability and new experimental tools are needed to properly evaluate sleep deprivation-induced anxiogenesis in rodents. Copyright © 2016 Elsevier Ltd. All rights reserved.

  16. Striatal increase of neurotrophic factors as a mechanism of nicotine protection in experimental parkinsonism.

    Science.gov (United States)

    Maggio, R; Riva, M; Vaglini, F; Fornai, F; Racagni, G; Corsini, G U

    1997-01-01

    The repeated finding of an apparent protective effect of cigarette smoking on the risk of Parkinson's disease is one of the few consistent results in the epidemiology of this disorder. Among the innumerous substances that originate from tobacco smoke, nicotine is by far the most widely studied, and the most likely candidate for a protective effect against neuronal degeneration in Parkinson's disease. Nicotine is a natural alkaloid that has considerable stimulatory effects on the central nervous system (CNS). Its effects on the CNS are mediated by the activation of neuronal heteromeric acetylcholine-gated ion channel receptors (nAChR, also termed nicotinic acetylcholine receptors). In the present study, we describe the neuroprotective effects of (-)nicotine in two animal models of parkinsonism: the diethyldithiocarbamate (DDC)-induced enhancement of 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) toxicity in mice, and the methamphetamine-induced neurotoxicity in rats and mice. In parallel experiments, we found that (-)nicotine induces the basic fibroblast growth factor (FGF-2) and the brain-derived neurotrophic factor (BDNF) in rat striatum. As FGF-2 and BDNF have been reported to be neuroprotective for dopaminergic cells, our data indicate that the increase in neurotrophic factors is a possible mechanism by which (-)nicotine protects from experimental parkinsonisms. Moreover, they suggest that nAChR agonists could be of potential benefit in the progression of Parkinson's disease.

  17. Psychological and neural mechanisms of experimental extinction: a selective review.

    Science.gov (United States)

    Delamater, Andrew R; Westbrook, R Frederick

    2014-02-01

    The present review examines key psychological concepts in the study of experimental extinction and implications these have for an understanding of the underlying neurobiology of extinction learning. We suggest that many of the signature characteristics of extinction learning (spontaneous recovery, renewal, reinstatement, rapid reacquisition) can be accommodated by the standard associative learning theory assumption that extinction results in partial erasure of the original learning together with new inhibitory learning. Moreover, we consider recent behavioral and neural evidence that supports the partial erasure view of extinction, but also note shortcomings in our understanding of extinction circuits as these relate to the negative prediction error concept. Recent work suggests that common prediction error and stimulus-specific prediction error terms both may be required to explain neural plasticity both in acquisition and extinction learning. In addition, we suggest that many issues in the content of extinction learning have not been fully addressed in current research, but that neurobiological approaches should be especially helpful in addressing such issues. These include questions about the nature of extinction learning (excitatory CS-No US, inhibitory CS-US learning, occasion setting processes), especially as this relates to studies of the micro-circuitry of extinction, as well as its representational content (sensory, motivational, response). An additional understudied problem in extinction research is the role played by attention processes and their underlying neural networks, although some research and theory converge on the idea that extinction is accompanied by attention decrements (i.e., habituation-like processes). Copyright © 2013 Elsevier Inc. All rights reserved.

  18. FRAME, animal experimentation and the Three Rs: past, present and future.

    Science.gov (United States)

    Balls, Michael

    2009-12-01

    At the opening of a meeting to celebrate the 50th anniversary of the publication of The Principles of Humane Experimental Technique, by W.M.S. Russell and R.L. Burch, and the 40th anniversary of the establishment of FRAME, some comments on the early days of the Charity are made, with particular reference to the special contributions made by its founder-Chairman, Dorothy Hegarty, and the author's own appointment as a Trustee, and later as Chairman. Reference is made to some key events and successes, and especially to the importance of FRAME's move from London to Nottingham, and the establishment of an ongoing collaboration with the University of Nottingham, including the setting-up of the FRAME Alternatives Laboratory. 2009 FRAME.

  19. Experimental and computational investigation of temperature effects on soot mechanisms

    Directory of Open Access Journals (Sweden)

    Bi Xiaojie

    2014-01-01

    Full Text Available Effects of initial ambient temperatures on combustion and soot emission characteristics of diesel fuel were investigated through experiment conducted in optical constant volume chamber and simulation using phenomenological soot model. There are four difference initial ambient temperatures adopted in our research: 1000 K, 900 K, 800 K and 700 K. In order to obtain a better prediction of soot behavior, phenomenological soot model was revised to take into account the soot oxidation feedback on soot number density and good agreement was observed in the comparison of soot measurement and prediction. Results indicated that ignition delay prolonged with the decrease of initial ambient temperature. The heat release rate demonstrated the transition from mixing controlled combustion at high ambient temperature to premixed combustion mode at low ambient temperature. At lower ambient temperature, soot formation and oxidation mechanism were both suppressed. But finally soot mass concentration reduced with decreasing initial ambient temperature. Although the drop in ambient temperature did not cool the mean in-cylinder temperature during the combustion, it did shrink the total area of local high equivalence ratio, in which soot usually generated fast. At 700 K initial ambient temperature, soot emissions were almost negligible, which indicates that sootless combustion might be achieved at super low initial temperature operation conditions.

  20. An Experimental Evaluation of Mechanical Properties of Hybrid Reinforcements

    Science.gov (United States)

    Sai Kumar, A.; Ganesan, G.; Karthikeyan, K.

    2017-07-01

    This paper presents the mechanical properties of unidirectional hybrid reinforcements formed from continuous fibres impregnated with a fibre binding material which are used for reinforcing the concrete. Recently FRP (Fibre Reinforced Polymer) manufacturers and suppliers have been increased all over the world because of the superior performance of FRP products in the construction industry. Its non-corrosive nature has turned the attention of many researchers to make several studies on different type of FRP products. Through a vast research, several standards also have been formulated. In this regard a new combination of FRP materials is tried in this paper and its properties have been derived. Carbon fibre and glass fibres fuse in this study to form a new hybrid rebar. The design properties such as tensile strength, tensile modulus, and compressive strength have been studied as per ASTM standards and it has been identified that the Hybrid rebar show a superior performance in comparison with GFRP (Glass FRP) and Steel rebars. This extraordinary performance of hybrid composite material increases the extensive engineering applications such as transport industry, aeronautics, naval, automotive industries.

  1. Experimental Study on Basic Mechanical Properties of BFRP Bars

    Science.gov (United States)

    Fan, Xiaochun; Xu, Ting; Zhou, Zhengrong; Zhou, Xun

    2017-10-01

    Basalt Fiber Reinforced Polymer (BFRP) bars have the advantages of corrosion resistance, high strength, light weight, good dielectric properties, and they are new type of green reinforced alternative material. In order to determine the mechanical properties of BFRP bars, the tensile strength of basalt fiber bars was necessary to be studied. The diameters of the basalt fiber bars were compared by means of uniaxial tensile test in this article. Then the stress-strain curve can be drawn out. The results show that the stress - strain curve of BFRP bars present straight line relation, and there is no sign before failure; there is no yield platform on the stress-strain curve of BFRP bars, which are typical brittle material;the tensile strength of BFRP bars is about 3 times higher than that of ordinary steel bars. and the elastic modulus is about 1/5 of that of ordinary steel; the ultimate tensile strength of BFRP bars varies little with the increase of diameter, but there exist some differences in modulus values.

  2. An animal experimental study of porous magnesium scaffold degradation and osteogenesis

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Y.J.; Yang, Z.Y. [The Third Hospital of Hebei Medical University, Shijiazhuang (China); Tan, L.L. [Institute of Metal Research, Chinese Academy of Sciences, Shenyang (China); Li, H. [The Third Hospital of Hebei Medical University, Shijiazhuang (China); Zhang, Y.Z. [The Third Hospital of Hebei Medical University, Shijiazhuang (China); The Key Orthopedic Biomechanics Laboratory of Hebei Province, Shijiazhuang (China)

    2014-08-19

    Our objective was to observe the biodegradable and osteogenic properties of magnesium scaffolding under in vivo conditions. Twelve 6-month-old male New Zealand white rabbits were randomly divided into two groups. The chosen operation site was the femoral condyle on the right side. The experimental group was implanted with porous magnesium scaffolds, while the control group was implanted with hydroxyapatite scaffolds. X-ray and blood tests, which included serum magnesium, alanine aminotransferase (ALT), creatinine (CREA), and blood urea nitrogen (BUN) were performed serially at 1, 2, and 3 weeks, and 1, 2, and 3 months. All rabbits were killed 3 months postoperatively, and the heart, kidney, spleen, and liver were analyzed with hematoxylin and eosin (HE) staining. The bone samples were subjected to microcomputed tomography scanning (micro-CT) and hard tissue biopsy. SPSS 13.0 (USA) was used for data analysis, and values of P<0.05 were considered to be significant. Bubbles appeared in the X-ray of the experimental group after 2 weeks, whereas there was no gas in the control group. There were no statistical differences for the serum magnesium concentrations, ALT, BUN, and CREA between the two groups (P>0.05). All HE-stained slices were normal, which suggested good biocompatibility of the scaffold. Micro-CT showed that magnesium scaffolds degraded mainly from the outside to inside, and new bone was ingrown following the degradation of magnesium scaffolds. The hydroxyapatite scaffold was not degraded and had fewer osteoblasts scattered on its surface. There was a significant difference in the new bone formation and scaffold bioabsorption between the two groups (9.29±1.27 vs 1.40±0.49 and 7.80±0.50 vs 0.00±0.00 mm{sup 3}, respectively; P<0.05). The magnesium scaffold performed well in degradation and osteogenesis, and is a promising material for orthopedics.

  3. Influence of a productive solution of uranium on some biochemical parameters of blood of an organism at experimental animals

    International Nuclear Information System (INIS)

    Svambaev, Z.A.; Svambaev, E.A.; Sultanbekov, G.A; Tusupbekova, S.T.

    2010-01-01

    In the work authors inform results on studying influence of a productive solution of uranium on some biochemical parameters of blood of an organism at experimental animals. It is established that all samples of a productive solution of uranium possesses high toxicity and causes destruction of experimental animals with infringement of a picture of blood. Experiments on influence on biochemical and hematology defined parameters of blood on chickens - broilers and on which female quails from daily age raised on cellular batteries in communities on 50 heads in conditions adequate to the requirement. Fed in plenty with the dry forages prepared according to 'Recommendations on the normalized feeding an agricultural bird' (1996), recipes 5-2; 6-1. To chickens in plenty allowed water from auto drinking bowls. Conditions of a micro climate corresponded to hygienic requirements. At carrying out of experiences studied the following parameters: preservation of a livestock, the reason of a withdrawal, weight of a body - weekly up to the end of experience, consumption of a forage, an expense of a forage for 1 kg of a gain have established weight of a body the methods standard in poultry farming. After application of a productive solution took blood from under wings of a vein and in blood have established maintenance of hemoglobin, quantity of red cells, leukocytes and a leukocyte of the formula, the maintenance of calcium and phosphorus. An application of a productive solution for experimental birds for the fifth day has caused clinical symptoms of a poisoning and destruction in groups. At the survived birds in blood it has been established changes biochemical and hematology. Week age chickens of skilled group lagged behind in growth development in comparison with control group on 30 % and at the end of the skilled period skilled have lagged behind in growth and development on 62 %. Among a livestock of chickens of skilled group of a case was more on 53 % on comparisons with the

  4. Mechanisms of impaired exercise capacity in short duration experimental hyperthyroidism.

    Science.gov (United States)

    Martin, W H; Spina, R J; Korte, E; Yarasheski, K E; Angelopoulos, T J; Nemeth, P M; Saffitz, J E

    1991-01-01

    To investigate the mechanism of reduced exercise tolerance in hyperthyroidism, we characterized cardiovascular function and determinants of skeletal muscle metabolism in 18 healthy subjects aged 26 +/- 1 yr (mean +/- SE) before and after 2 wk of daily ingestion of 100 micrograms of triiodothyronine (T3). Resting oxygen uptake, heart rate, and cardiac output increased and heart rate and cardiac output at the same submaximal exercise intensity were higher in the hyperthyroid state (P less than 0.05). However, maximal oxygen uptake decreased after T3 administration (3.08 +/- 0.17 vs. 2.94 +/- 0.19 l/min; P less than 0.001) despite increased heart rate and cardiac output at maximal exercise (P less than 0.05). Plasma lactic acid concentration at an equivalent submaximal exercise intensity was elevated 25% (P less than 0.01) and the arteriovenous oxygen difference at maximal effort was reduced (P less than 0.05) in the hyperthyroid state. These effects were associated with a 21-37% decline in activities of oxidative (P less than 0.001) and glycolytic (P less than 0.05) enzymes in skeletal muscle and a 15% decrease in type IIA muscle fiber cross-sectional area (P less than 0.05). Lean body mass was reduced (P less than 0.001) and the rates of whole body leucine oxidation and protein breakdown were enhanced (P less than 0.05). Thus, exercise tolerance is impaired in short duration hyperthyroidism because of decreased skeletal muscle mass and oxidative capacity related to accelerated protein catabolism but cardiac pump function is not reduced. PMID:1752962

  5. MECHANISMS OF MELATONIN EFFECTS UPON IMMUNE STATE IN EXPERIMENTAL DESYNCHRONOSES PRODUCED UNDER THE LED ILLUMINATION CONDITIONS

    Directory of Open Access Journals (Sweden)

    M. V. Osikov

    2015-01-01

    Full Text Available Disorders of immune state in desynchronosis may be associated with reduced concentrations of melatonin in blood, thus being a prerequisite for pharmacological correction of appropriate homeostatic changes. The purpose of this work was to explore some mechanisms of exogenous melatonin actions upon parameters of innate and adaptive immunity in experimental model of desynchronosis under the conditions of LED illumination. The study was performed with 196 adult guinea pigs. Light desynchronosis was produced by day-and-night illumination of the animals having been continued for 30 days. Melatonin was administered applied per os daily at the total dose of 30 mg/kg. A solution of melatonin in isotonic NaCl solution was prepared from the Melaxen drug (INN: melatonin, “Unipharm Inc.,” USA ex tempore. To study innate immunity of blood cells, we determined leukocyte numbers, WBC differential counts, and functional activity of phagocytes, as spontaneous and induced NBT test, as well as engulfment of polystyrene latex particles. Th1-specific immune response was studied according to degree of delayed type hypersensitivity reaction; Th2-dependent response was assessed as the numbers of antibody-forming cells in the spleen of the animals after immunization with allogeneic erythrocytes. Serum concentrations of interleukin 4 (IL-4, interferon-gamma (IFNγ, melatonin, and cortisol were measured by enzyme immunoassay, using the “Immulayt 2000” (USA with guinea pigspecific test systems. It was found that experimental desynchronosis was associated with leukocytosis, lymphoand monocytopenia, activation of oxygen-dependent metabolism of blood phagocytes, suppression of Th1-and Th2-dependent immune response. Desynchronosis was also accompanied by decreased concentrations of serum melatonin, IFNγ and IL-4, along with increased cortisol concentrations. Reduced IFNγ and IL-4 amounts was associated with decreased melatonin concentrations

  6. Consistency of feed efficiency ranking and mechanisms associated with inter-animal variation among growing calves.

    Science.gov (United States)

    Asher, A; Shabtay, A; Cohen-Zinder, M; Aharoni, Y; Miron, J; Agmon, R; Halachmi, I; Orlov, A; Haim, A; Tedeschi, L O; Carstens, G E; Johnson, K A; Brosh, A

    2018-04-03

    This study investigated the possible mechanisms for explaining interanimal variation in efficiency of feed utilization in intact male Holstein calves. Additionally, we examined whether the feed efficiency (FE) ranking of calves (n = 26) changed due to age and/or diet quality. Calves were evaluated during three periods (P1, P2, and P3) while fed a high-quality diet (calculated mobilizable energy [ME] of 11.8 MJ/kg DM) during P1 and P3, and a low-quality diet (calculated ME of 7.7 MJ/kg DM) during P2. The study periods were 84, 119, and 127 d, respectively. Initial ages of the calves in P1, P2, and P3 were 7, 11, and 15 mo, respectively, and initial body weight (BW) were 245, 367, and 458 kg, respectively. Individual dry matter intake (DMI), average daily gain (ADG), diet digestibility, and heat production (HP) were measured in all periods. The measured FE indexes were: residual feed intake (RFI), the gain-to-feed ratio (G:F), residual gain (RG), residual gain and intake (RIG), the ratio of HP-to-ME intake (HP/MEI), and residual heat production (RHP). For statistical analysis, animals' performance data in each period, were ranked by RFI, and categorized into high-, medium-, and low-RFI groups (H-RFI, M-RFI, and L-RFI). RFI was not correlated with in vivo digestibility, age, BW, BCS, or ADG in all three periods. The L-RFI group had lowest DMI, MEI, HP, retained energy (RE), and RE/ADG. Chemical analysis of the longissimus dorsi muscle shows that the L-RFI group had a higher percentage of protein and a lower percentage of fat compared to the H-RFI group. We suggested that the main mechanism separating L- from H-RFI calves is the protein-to-fat ratio in the deposited tissues. When efficiency was related to kg/day (DMI and ADG) and not to daily retained energy, the selected efficient L-RFI calves deposited more protein and less fat per daily gain than less efficient H-RFI calves. However, when the significant greater heat increment and maintenance energy requirement of

  7. 'If you are empathetic you care about both animals and people. I am a nurse and I don't like to see suffering anywhere': Findings from 103 healthcare professionals on attitudes to animal experimentation.

    Science.gov (United States)

    Dignon, Andrée

    2016-11-01

    This report presents qualitative and quantitative data from 103 UK healthcare professionals describing attitudes to the current system of animal testing (to produce medicines and health interventions). To gather qualitative testimony, these healthcare professionals were organised into six separate focus groups (of 18, 17, 17, 15, 17 and 19 participants) where they were asked 'what is your opinion about the current system of animal testing?' The study focussed on attitudes to the current system rather than attitudes to animal testing in general. The healthcare professionals also completed a quantitative attitude scale questionnaire consisting of 20 statements (all favourable) towards the system of animal testing as currently practised. Statements such as 'Testing agencies abide by legislation to safeguard animal welfare' were displayed and the healthcare professionals were invited to agree or disagree with these statements. The results from both the quantitative and qualitative data suggest that healthcare professionals were opposed to the current system of animal experimentation.

  8. Animal experimental study of safety for a self-made vena cava stent-filter

    International Nuclear Information System (INIS)

    Qin Dingwen; Shi Haibin; Liu Sheng; Li Linsun

    2008-01-01

    Objective: To evaluate the safety of a self-made vena cava stent-filter(VCSF)for prevention of pulmonary embolism. Methods: Fusiform unmhrella-like vena cava filter was made of Nitinol wires and stainless steel metal pole, and then ten mongrel dogs were implanted with these self-made filters and divided into 5 groups according to the different periods (2, 3, 4, 5 and 6 w) of filter placement, with 2 dogs in each group. After the VCSFs were placed in inferior vena cava via the right femoral vein approach, the dogs in each group were bred for 2-6 weeks, respectively. The blood flow of inferior vena cava and the position of the filters were inspected by inferior vena-cavography according to the indwelling periods. Finally the metal pole was retrieved via the femoral vein, leaving the VCSF as permanent venousz stent. The feasibility of retrieval and the free state of filter net with the adhering vascular wall were evaluated. Laparotomies were performed to remove the inferior vena cava from the animals for gross and electron microscopic examinations of the inferior vena cava intimal changes of the involved segment. Results: All 10 VCSFs were placed at the right positions of the dogs successfully. Angiography showed patent inferior vena cava without filter thrombosis at 2-6 weeks. There were no tilting and migration of the filter and all the metal poles were successfully retrieved. The superior and inferior extremities of filter nets could be set free with all the filters turning into venous stents. Postmortem displayed retroperitoneal hemorrhage and caval thrombosis. The barbs of the filters penetrated over the caval adventitial coat. Under electron microscope, a thin layer of neointima already covered the braiding net of VCSFs at 2 weeks after the deployment. The tunica intima became slightly thick at 3-4 weeks and with moderate proliferation at 5-6 weeks. Conclusions: The self-made vena cava stent-filter possesses rather long indwelling period according to the

  9. Amperometric cell for subcutaneous detection of hydrogen sulfide in anesthetized experimental animals

    International Nuclear Information System (INIS)

    Nagy, L; Nagy, G; Filotás, D; Boros, M; Pozsgai, G; Pintér, E

    2014-01-01

    Hydrogen sulfide (H 2 S) is a toxic gas. It has been recognized that H 2 S evolving in biochemical reactions in living organisms has an important role in different physiologic processes. Nowadays, H 2 S is known as an endogenous messenger molecule. Natural sulfurous spring water has been proved beneficial in the therapy of diseases of the skin and other organs (Boros et al 2013). In vivo real-time detection of local H 2 S concentration is an important but challenging task. We developed a two-electrode amperometric cell for selective subcutaneous detection of H 2 S in anesthetized mice. The cell is a small size implantable gas sensor containing a platinum disc anode and a silver cathode. The selectivity is provided by a membrane permeable only by gases. There is a buffered reversible electrochemical mediator solution in an oxidized form inside the cell. As gaseous H 2 S penetrates into the cell the mediator is reduced, and +0.4 V versus the reference is employed on the platinum working electrode. The reduced mediator is oxidized on the anode surface. The current provides an analytical signal representing the concentration of H 2 S. Appropriate shape, size and membrane material were selected, and optimal working parameters—such as mediator concentration, pH and cell voltage—were determined in vitro. The lower limit of detection in the stirred sample solution at pH = 5.5 was as small as 9.4  ×  10 −7  M and a dynamic concentration range of 0–6  ×  10 –4  M could be achieved. The detecting surfaces of the cell were covered with freshly dissected mouse skin to test dermal H 2 S permeability. In other experiments, the cell was implanted subcutaneously in an anesthetized mouse and the animal was submerged in a buffer solution containing different concentrations of H 2 S so that the skin surface over the sensor was covered by the solution. Measurements of subcutaneous H 2 S concentration were taken. The experiments clearly proved that H 2 S

  10. Labeling method of 17-allylamino, 17-demethoxygeldanamycin with 131I and its biodistribution in experimental animals

    International Nuclear Information System (INIS)

    Jiang Xinyu; Liu Lu; Gao Wen; Chen Daozhen; Huang Ying; Yang Min; Luo Shineng

    2008-01-01

    Objective: The aims of the study were to find out the optimal 131 I labeling method with 17-allylamino, 17-demethoxygeldanamycin (17-AAG) and also to study its biodistribution in animals. Methods: 131 I-17-AAG was prepared by the reaction of 17-AAG with Na 131 I in the presence of hydrogen peroxide. The labeling efficiency and the stability of 131 I-17-AAG were measured by paper chromatograph. The biodistribution in the ICR normal mice was observed by the blood samplings and major organs that were taken out from mice at 0.5, 1, 4, 8, 24 h after 131 I-17-AAG injection through tail veins. VX2 tumor was also implanted in rabbit liver for in vivo imaging with SPECT. Results: The optimal labeling conditions of 17-AAG with mi were determined. The labeling efficiency was 85.65%. The radiochemical purity of 131 I- 17-AAG in acetoacetate solution was (96.51 ± 0.80)% after purification and its radiochemical purity in normal saline solution was (95.57 ± 0.09)%. The radiochemical purity could keep to 90% in normal saline after 5 d at 4 degree C. The biodistribution study in normal mice showed that the uptake (percentage activity of injection dose per gram of tissue, % ID/g) in liver and kidney was less than that in cholecyst [(3.0963 ± 1.3394) %ID/g] at 0.5 h post-injection, and the uptake in stomach and intestine reached to the highest level at 4 h post-injection. The SPECT images showed that the 131 I-17-AAG was obviously concentrated in the tumor after injection at 2 h and 4 d, 6 d, 14 d with the highest tumor to non-tumor (T/NT) radioactivity ratio of 10.36. Conclusions: The labeling method of 17-AAG with 131 I was successfully established. The 131 I-17-AAG in normal saline had a good stability. The main biodistribution in mice was in digestive system and was excreted through the intestinal tract. The SPECT images showed that 131 I-17-AAG might be a potential target-directed agent to the tumor. (authors)

  11. Effect of verapamil on bronchial goblet cells of asthma: an experimental study on sensitized animals.

    Science.gov (United States)

    Khakzad, Mohammad Reza; Mirsadraee, Majid; Mohammadpour, Amirhooshang; Ghafarzadegan, Kamram; Hadi, Raziye; Saghari, Mahdiye; Meshkat, Mojtaba

    2012-04-01

    Goblet cell hyperplasia (GCH) and mucus hypersecretion in the airway is recognized as an important contributor to morbidity and mortality in asthma and COPD. Verapamil is a calcium channel blocker that binds to the alpha-subunit of L-type calcium channels and inhibits the mucin gene via the calmodulin and CaM kinase pathway. The objective of this study was to determine the in vivo effect of verapamil on GCH and eosinophilic inflammation in sensitized mice. Male BALB/c mice were sensitized to ovalbumin using the standard method. Two groups of animals were received verapamil via an intramuscular injection: 1-low dose (0.5 mg/kg/day for two weeks), 2-high dose (1.5 mg/kg/day for two weeks). Serum and bronchoalveolar lavage fluid (BALF) was collected and analyzed for inflammatory cells, interferon-γ and IL-4. The left lung was sent for histopathological evaluation, especially for periodic acid-Schiff (PAS), to identify goblet cells in the epithelium. The degree of inflammatory cell infiltration, including eosinophils, mucus plugging, and smooth muscle thickness of the airways were classified on a semi quantitative scale. Inflammatory cell infiltration in peribronchial and perivascular areas was observed in all sensitized groups. Eosinophils percentage in the BALF significantly decreased in verapamil-treated mice compared with sensitized mice (from 19.8% in asthmatic to 5.4% for low dose and 4.4% for high dose). The ratio of airway goblet cells per epithelial cells were significantly lower in verapamil-treated mice versus sensitized mice (1.57±1.30% for low dose; 1.50±0.93% for high dose versus 12.93±7.55%, Pcells decreased significantly in verapamil-treated mice versus sensitized mice (mean score was 1.45±0.30 for low dose; 0.81±1.00 for high dose versus 2.85±0.86 in the sensitized control group, P<0.05, respectively). The concentration of serum and BALF-IFN-γ in verapamil-treated mice markedly increased by the verapamil treatment when compared to sensitized

  12. The selective cathepsin K inhibitor MIV-711 attenuates joint pathology in experimental animal models of osteoarthritis.

    Science.gov (United States)

    Lindström, Erik; Rizoska, Biljana; Tunblad, Karin; Edenius, Charlotte; Bendele, Alison M; Maul, Don; Larson, Michael; Shah, Neha; Yoder Otto, Valerie; Jerome, Chris; Grabowska, Urszula

    2018-03-09

    MIV-711 is a highly potent and selective cathepsin K inhibitor. The current article summarizes the therapeutic effects of MIV-711 on joint pathology in rabbits subjected to anterior cruciate ligament transection (ACLT), and the prophylactic effects on joint pathology in dogs subjected to partial medial meniscectomy, two surgical models of osteoarthritis (OA). Starting 1 week after surgery, rabbits were dosed daily via oral gavage with either MIV-711 or vehicle (n = 7/group) for 7 weeks. The four treatment groups were: (1) sham + vehicle; (2) ACLT + vehicle; (3) ACLT + MIV-711, 30 µmol/kg and (4) ACLT + MIV-711, 100 µmol/kg. Subchondral bone and articular cartilage structures were assessed by µCT, histomorphometry, and scoring. Dogs subjected to partial medial meniscectomy received either MIV-711 (30 µmol/kg) or vehicle (n = 15/group) via oral gavage once daily, starting 1 day before meniscectomy, for 28 days. Cartilage degradation was assessed at the macroscopic and microscopic levels. The exposures of MIV-711 were assessed in both studies and biomarkers reflecting bone resorption (HP-1 in rabbits, CTX-I in dogs) and cartilage degradation (CTX-II) were measured. In ACLT rabbits, MIV-711 decreased HP-1 levels by up to 72% (p subchondral bone plate and reduced trabecular bone volume in the femur and tibia. These effects were reversed by MIV-711. ACLT resulted in cartilage thickening, which was attenuated by MIV-711. MIV-711 did not affect osteophyte formation or Mankin scores. In dogs, MIV-711 reduced CTX-I and CTX-II levels by 86% (p subchondral bone loss and partially attenuates cartilage pathology in two animal models of OA. These beneficial effects of MIV-711 on joint pathology are observed in conjunction with decreases in bone and cartilage biomarkers that have been shown to be clinically attainable in human. The data support the further development of MIV-711 for the treatment of OA.

  13. REAC regenerative treatment efficacy in experimental chondral lesions: a pilot study on ovine animal model

    Directory of Open Access Journals (Sweden)

    Sanna Passino E

    2017-09-01

    Full Text Available Eraldo Sanna Passino,1,2 Stefano Rocca,1 Sabrina Caggiu,1 Nicolò Columbano,1,2 Alessandro Castagna,3 Vania Fontani,3–5 Salvatore Rinaldi3–51Department of Veterinary Medicine, University of Sassari, Sassari, Italy; 2Comparative Surgery Research Laboratory, University of Sassari, Sassari, Italy; 3Department of Regenerative Medicine, Rinaldi Fontani Institute, Florence, Italy; 4Research Department, Rinaldi Fontani Foundation, Florence, Italy; 5Research Department, IRF Shanghai Biomedical Sciences, Shanghai, People’s Republic of China Abstract: Radioelectric asymmetric conveyor (REAC technology is a platform designed to optimize cell polarity. Cell polarity is a universal biological phenomenon that is implicated in cell differentiation, proliferation, morphogenesis, aging, and rejuvenation. In this work, we investigate a timing and administration protocol for tissue optimization regenerative treatment type C, in order to treat aging-related chondral damage or injuries and gain insights into regenerative processes of articular cartilage in humans. The chondral lesion produced in this study in an animal model (6 knee joints of 4 adult sheep was 6 mm in diameter and about 2 mm deep. These lesions, which did not involve subchondral bone, tend to increase in size and depth and are not completely repaired with normal hyaline articular cartilage since adult articular cartilage is avascular and has a very slow turnover at the cellular and molecular level. Moreover, the hydration of articular cartilage is reduced with aging and with decreased mitotic activity, synthesis, and population size of chondrocytes. Six months posttreatment, lesions appeared filled, though not completely, with newly generated tissue of the light opalescent color of healthy articular cartilage, which otherwise covered the underlying subchondral bone. The newly formed tissue surface appeared to be quite regular. Nearly complete regeneration of subchondral bone occurred, with

  14. Nephro-protective potential of Morus alba, a prospective experimental study on animal models.

    Science.gov (United States)

    Ullah, Naveed; Khan, Mir Azam; Khan, Salimullah; Ahmad, Habib; Asif, Afzal Haq; Khan, Taous

    2016-01-01

    Morus alba L. (Moraceae) is traditionally used for the treatment of urinary incontinency due its strong diuretic properties. The present study explores the renal protective effects of M. alba, due to its free radical scavenging properties, in order to provide experimental evidence for its established use. Ethanolic extract (200 mg/kg/d) derived from M. alba fruit was employed in rabbits as a co-therapy (GM-al) with gentamicin (80 mg/kg/d) for a period of 3 weeks. Biochemical kidney functioning parameters, urinary isozymes, and histopathological examination were performed. The results showed that ethanol extract of Morus alba L. prevented alterations in serum creatinine (4.02 ± 0.14, p alba with gentamicin prevented renal functioning alterations expected with the use of gentamicin alone. Therefore, it can be concluded that M. alba to protect from kidney damage, which may be because of its free radical scavenging and diuretic properties.

  15. [Use of adipose-derived stem cells in an experimental rotator cuff fracture animal model].

    Science.gov (United States)

    Barco, R; Encinas, C; Valencia, M; Carrascal, M T; García-Arranz, M; Antuña, S

    2015-01-01

    Rotator cuff repairs have shown a high level of re-ruptures. We hypothesized that the use of adipose-derived stem cells (ASC) could improve the biomechanical and histological properties of the repair. Controlled experimental study conducted on 44 BDIX rats with section and repair of the supraspinatus tendon and randomization to one of three groups: group A, no intervention (control); group B, local applications of a fibrin sealant; and group C, application of the fibrin sealant with 2 x 10(6) ASC. At 4 and 8 weeks a biomechanical and histological analysis was performed. There were no differences in load-to-failure at 4 and 8 weeks between groups. The load-to-failure did increase between week 4 and week 8. Histologically the tendon-to bone union showed a disorganized fibrovascular tissue. Group C showed a different inflammatory pattern, with less presence of neutrophils and more presence of plasma cells. The use of ASC does not improve the biomechanical or histological properties of the repair site. More studies are needed to improve techniques that enhance the healing site of the repair. Copyright © 2014 SECOT. Published by Elsevier Espana. All rights reserved.

  16. The nonstructural proteins of Nipah virus play a key role in pathogenicity in experimentally infected animals.

    Directory of Open Access Journals (Sweden)

    Misako Yoneda

    Full Text Available Nipah virus (NiV P gene encodes P protein and three accessory proteins (V, C and W. It has been reported that all four P gene products have IFN antagonist activity when the proteins were transiently expressed. However, the role of those accessory proteins in natural infection with NiV remains unknown. We generated recombinant NiVs lacking V, C or W protein, rNiV(V-, rNiV(C-, and rNiV(W-, respectively, to analyze the functions of these proteins in infected cells and the implications in in vivo pathogenicity. All the recombinants grew well in cell culture, although the maximum titers of rNiV(V- and rNiV(C- were lower than the other recombinants. The rNiV(V-, rNiV(C- and rNiV(W- suppressed the IFN response as well as the parental rNiV, thereby indicating that the lack of each accessory protein does not significantly affect the inhibition of IFN signaling in infected cells. In experimentally infected golden hamsters, rNiV(V- and rNiV(C- but not the rNiV(W- virus showed a significant reduction in virulence. These results suggest that V and C proteins play key roles in NiV pathogenicity, and the roles are independent of their IFN-antagonist activity. This is the first report that identifies the molecular determinants of NiV in pathogenicity in vivo.

  17. Antipyretic activity of the extracts of Hibiscus sabdariffa calyces L. in experimental animals

    Directory of Open Access Journals (Sweden)

    Wantana Reanmongkol

    2007-03-01

    Full Text Available The effects of the extracts from Hibiscus sabdariffa calyces L. (H. sabdariffa on nociceptive response using writhing, hot plate and formalin test in mice and the antipyretic activity in yeast-induced fever in rats, were examined. Anti-inflammatory activity was also investigated on carrageenin-induced paw edema in rats. No acute toxicity was observed in mice after oral administration of the ethanol and aqueous extract of H. sabdariffa calyces at the dose of 15 g/kg. Oral administration of the ethanol extract at the dose of 800 mg/kg significantly decreased the number of contortions and stretchings induced by acetic acid in mice. The aqueous extracts had no effect on this test. Neither the ethanol nor aqueous extract had an effect in the formalin and hot plate tests in mice. The ethanol and the vacuum dried extract of H. sabdariffa calyces (200-800 mg/kg, p.o. decreased the yeast-induced fever in rats. The H. sabdariffa extract had no effect on carrageenininduced paw edema in rats. These results suggest that the ethanol and aqueous extract (vacuum dry of H. sabdariffa calyces possess antipyretic action through mechanisms that are different from that of aspirin.

  18. Evaluation of Biochemical Changes in Experimental Animals Treated with Some Anticancer and Radiosynthetizers

    International Nuclear Information System (INIS)

    EL-Shawy, O.E.M.

    2009-01-01

    Cancer constitutes the largest cause of mortality in the world and claims over 6 million lives every year (Abdullaev et al. 2000).It is a disease in which cellular growth regulatory networks are disrupted(Chen et al.2003). An extremely promising strategy for cancer prevention today is chemo prevention, which is defined as the use of synthetic or natural agents (alone or in combination) to block the development of cancer in humans (Gupta et al. 2004). Most of anticancer drugs have side effects on human normal cells when they were used to treat tumor cells (Bi and Jiang ,2006).Therefore cancer drugs development has moved from conventional cytotoxic chemotherapeutics to a more mechanism-based targeted approach towards the common goal of tumor growth arrest (McLaughlin and La Thangue 2004). Histones are a family of nuclear proteins that interact with DNA, resulting in DNA being wrapped around a core of histone octamer within the nucleosome (Rasheed et al. 2008).They may act through the transcriptional reactivation of dormant tumor suppressor genes and they also modulate expression of several other genes related to cell cycle, apoptosis, and angiogenesis (Shankar ans Srivastava, 2008). Histone acetylation is a reversible process: histone acetyl transferases (HAT) transfer the acetyl moiety from acetyl coenzyme A to the lysine, and histone de acetylases (HDAC) remove the acetyl groups reestablishing the positive charge in the histones (Fang, 2005).In particular, imbalance in histone acetylation can lead to changes in chromatin structure and transcriptional dysregulation of genes that are involved in the control of proliferation, cell-cycle progression, differentiation and/or apoptosis

  19. Brain Mechanisms Underlying Individual Differences in Reaction to Stress: An Animal Model

    National Research Council Canada - National Science Library

    Siegel, Jerome

    1997-01-01

    .... We developed an animal model of this important dimension of behavior in which we reported that cats and rats who display high levels of exploration, activity, aggression, and risk taking show VEP...

  20. Effects of urbanization on animal behaviour : patterns, underlying mechanisms and ultimate causes

    OpenAIRE

    Miranda, Ana Catarina Sequeira Nunes Coutinho de

    2014-01-01

    Human-altered environmental conditions affect many species at the global scale. An extreme form of anthropogenic alteration is the existence and rapid increase of urban areas. A key question is how animals cope with urbanization. In order to live in cities, animals have to adjust their behaviour and life histories to the urban novel environment.The main objectives of this thesis were to investigate (i) the existence of behavioural changes related to the urbanization process, (ii) the ultimate...

  1. Animal mortality resulting from uniform exposures to photon radiations: Calculated LD50s and a compilation of experimental data

    International Nuclear Information System (INIS)

    Jones, T.D.; Morris, M.D.; Wells, S.M.; Young, R.W.

    1986-12-01

    Studies conducted during the 1950s and 1960s of radiation-induced mortality to diverse animal species under various exposure protocols were compiled into a mortality data base. Some 24 variables were extracted and recomputed from each of the published studies, which were collected from a variety of available sources, primarily journal articles. Two features of this compilation effort are (1) an attempt to give an estimate of the uniform dose received by the bone marrow in each treatment so that interspecies differences due to body size were minimized and (2) a recomputation of the LD 50 where sufficient experimental data are available. Exposure rates varied in magnitude from about 10 -2 to 10 3 R/min. This report describes the data base, the sources of data, and the data-handling techniques; presents a bibliography of studies compiled; and tabulates data from each study. 103 refs., 44 tabs

  2. A study of the anti-inflammatory effect of the leaves of Psidium guajava Linn. on experimental animal models

    Science.gov (United States)

    Dutta, Sarmistha; Das, Swarnamoni

    2010-01-01

    Introduction: The aim is to study the anti-inflammatory effect of the ethanolic extract of the leaves of Psidium guajava(PGE) on experimental animal models. Materials and Methods: Fresh leaves were collected, air-dried, powdered, and percolated in 95% ethanol. Acute toxicity test was done according to OECD guidelines. Four groups of animals of either sex, weighing 150–200g of the species Rattus norvegicus were taken for the study (n = 6). Group A was taken as control (3% gum acacia in 10 mL/kg body weight), Group B as test group (PGE 250 mg/kg body weight), Group C as test group (PGE 500 mg/kg body weight), and Group D as standard (Aspirin 100 mg/kg body weight). The animals were studied for acute inflammation by Carrageenan-induced rat paw edema, subacute inflammation by Granuloma pouch method, and chronic inflammation by Freund’s adjuvant-induced arthritis method. Statistical analysis was done by one-way analysis of variance followed by multiple comparison tests. Results: In acute inflammation, there was significant inhibition of paw edema in Groups B, C, and D in comparison with Group A (P < 0.05). In subacute inflammation, there was significant inhibition of exudate formation in Groups B, C, and D in comparison to Group A (P < 0.05). In chronic inflammation, there was significant inhibition of paw edema and inhibition of weight reduction in Groups B, C, and D compared with Group A. Downregulation of arthritis index was also significant in Groups B, C, and D in comparison with Group A (P < 0.05). Conclusion: The ethanolic extract of PGE has significant anti-inflammatory activity. PMID:21589759

  3. Initial study of sediment antagonism and characteristics of silver nanoparticle-coated biliary stents in an experimental animal model.

    Science.gov (United States)

    Tian, Yigeng; Xia, Mingfeng; Zhang, Shuai; Fu, Zhen; Wen, Qingbin; Liu, Feng; Xu, Zongzhen; Li, Tao; Tian, Hu

    2016-01-01

    Plastic biliary stents used to relieve obstructive jaundice are frequently blocked by sediment, resulting in loss of drainage. We prepared stents coated with silver nanoparticles (AgNPs) and compared their ability to resist sedimentation with Teflon stents in a beagle model of obstructive jaundice. AgNP-coated Teflon biliary stents were prepared by chemical oxidation-reduction and evaluated in an obstructive jaundice model that was produced by ligation of common bile duct (CBD); animals were randomized to two equal groups for placement of AgNP-coated or Teflon control stents. Liver function and inflammatory index were found to be similar in the two groups, and the obstruction was relieved. Stents were removed 21 days after insertion and observed by scanning and transmission electron microscopy. The AgNP coating was analyzed by energy dispersive X-ray analysis (EDXA), and the composition of sediment was assayed by Fourier-transform infrared (FTIR) spectroscopy. Electron microscopy revealed a black, closely adherent AgNP stent coating, with thicknesses of 1.5-6 µm. Sediment thickness and density were greater on Teflon than on AgNP-coated stents. EDXA confirmed the stability and integrity of the AgNP coating before and after in vivo animal experimentation. FTIR spectroscopy identified stent sediment components including bilirubin, cholesterol, bile acid, protein, calcium, and other substances. AgNP-coated biliary stents resisted sediment accumulation in this canine model of obstructive jaundice caused by ligation of the CBD.

  4. Recruiting "Friends of Medical Progress": Evolving Tactics in the Defense of Animal Experimentation, 1910s and 1920s.

    Science.gov (United States)

    Ross, Karen D

    2015-07-01

    In 1923, Thomas Barbour of Harvard announced the creation of a national lay organization, the Society of Friends of Medical Progress (FMP), to defend animal research in the United States against a resurgent antivivisection movement. After decades of successful behind-the-scenes lobbying and avoiding the public spotlight, medical scientists significantly altered their tactics and sought public engagement, at least by proxy. Although the authority of scientific medicine was rising, women's suffrage, the advent of the ballot initiative, and a growing alliance of antivivisectionists and other groups in opposition to allopathic medicine so altered the political landscape that medical scientists reconsidered formerly rejected ideas such partnering with laymen. Medical scientists, Walter B. Cannon and Simon Flexner chief among them, hoped that the FMP would relieve the scientists of a time-consuming burden and defend against government regulation of medical institutions without the charge of material self-interest. However, financial problems and the frequent conflicts that arose between the lay leadership and Flexner eventually undermined the FMP's value as a defender of animal experimentation and reveal the distrust of reformers like Flexner who did not believe that laymen could speak for scientific medicine. © The Author 2014. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  5. Establishment of Experimental Apparatus and Mechanical Test for SFR Metallic Fuel

    International Nuclear Information System (INIS)

    Kim, Sun Ki; Lee, Chong Tak; Oh, Seok Jin; Ko, Young Mo; Kim, Ki Hwan; Woo, Yoon Myung; Lee, Chan Bock

    2010-12-01

    U-Zr binary alloys and U-Zr-Ce ternary alloys as SFR surrogate metallic fuels were fabricated by a casting process. Tensile tests were performed to evaluate the mechanical properties of the fuels. As a results, the mechanical properties such as yield strength, ultimate tensile strength, and elongation were measured. In this report, these experimental results are presented

  6. Animal models of Duchenne muscular dystrophy: from basic mechanisms to gene therapy

    Science.gov (United States)

    McGreevy, Joe W.; Hakim, Chady H.; McIntosh, Mark A.; Duan, Dongsheng

    2015-01-01

    Duchenne muscular dystrophy (DMD) is a progressive muscle-wasting disorder. It is caused by loss-of-function mutations in the dystrophin gene. Currently, there is no cure. A highly promising therapeutic strategy is to replace or repair the defective dystrophin gene by gene therapy. Numerous animal models of DMD have been developed over the last 30 years, ranging from invertebrate to large mammalian models. mdx mice are the most commonly employed models in DMD research and have been used to lay the groundwork for DMD gene therapy. After ~30 years of development, the field has reached the stage at which the results in mdx mice can be validated and scaled-up in symptomatic large animals. The canine DMD (cDMD) model will be excellent for these studies. In this article, we review the animal models for DMD, the pros and cons of each model system, and the history and progress of preclinical DMD gene therapy research in the animal models. We also discuss the current and emerging challenges in this field and ways to address these challenges using animal models, in particular cDMD dogs. PMID:25740330

  7. Retention time variability as a mechanism for animal mediated long-distance dispersal.

    Directory of Open Access Journals (Sweden)

    Vishwesha Guttal

    Full Text Available Long-distance dispersal (LDD events, although rare for most plant species, can strongly influence population and community dynamics. Animals function as a key biotic vector of seeds and thus, a mechanistic and quantitative understanding of how individual animal behaviors scale to dispersal patterns at different spatial scales is a question of critical importance from both basic and applied perspectives. Using a diffusion-theory based analytical approach for a wide range of animal movement and seed transportation patterns, we show that the scale (a measure of local dispersal of the seed dispersal kernel increases with the organisms' rate of movement and mean seed retention time. We reveal that variations in seed retention time is a key determinant of various measures of LDD such as kurtosis (or shape of the kernel, thinkness of tails and the absolute number of seeds falling beyond a threshold distance. Using empirical data sets of frugivores, we illustrate the importance of variability in retention times for predicting the key disperser species that influence LDD. Our study makes testable predictions linking animal movement behaviors and gut retention times to dispersal patterns and, more generally, highlights the potential importance of animal behavioral variability for the LDD of seeds.

  8. Animal models of Duchenne muscular dystrophy: from basic mechanisms to gene therapy.

    Science.gov (United States)

    McGreevy, Joe W; Hakim, Chady H; McIntosh, Mark A; Duan, Dongsheng

    2015-03-01

    Duchenne muscular dystrophy (DMD) is a progressive muscle-wasting disorder. It is caused by loss-of-function mutations in the dystrophin gene. Currently, there is no cure. A highly promising therapeutic strategy is to replace or repair the defective dystrophin gene by gene therapy. Numerous animal models of DMD have been developed over the last 30 years, ranging from invertebrate to large mammalian models. mdx mice are the most commonly employed models in DMD research and have been used to lay the groundwork for DMD gene therapy. After ~30 years of development, the field has reached the stage at which the results in mdx mice can be validated and scaled-up in symptomatic large animals. The canine DMD (cDMD) model will be excellent for these studies. In this article, we review the animal models for DMD, the pros and cons of each model system, and the history and progress of preclinical DMD gene therapy research in the animal models. We also discuss the current and emerging challenges in this field and ways to address these challenges using animal models, in particular cDMD dogs. © 2015. Published by The Company of Biologists Ltd.

  9. Relative willingness to pay and surplus comparison mechanism in experimental auctions

    OpenAIRE

    COMBRIS Pierre; SEABRA PINTO Alexandra; GIRAUD HERAUD Eric

    2015-01-01

    We study the relative willingness-to-pay (WTP) of consumers according to the diversity of supply in a market and we show how the presence of substitutes for a given product leads to question the incentive mechanisms commonly used in experimental auctions. We propose a Surplus Comparison Mechanism (SCM) in order to yield WTP estimates which better take into account the choice set available to consumers. After showing the efficiency of this mechanism we test the SCM in a laboratory experiment, ...

  10. Hepatoprotective effect of Solanum xanthocarpum fruit extract against CCl4 induced acute liver toxicity in experimental animals.

    Science.gov (United States)

    Gupta, Ramesh K; Hussain, Talib; Panigrahi, G; Das, Avik; Singh, Gireesh Narayan; Sweety, K; Faiyazuddin, Md; Rao, Chandana Venkateswara

    2011-12-01

    To investigate the hepatoprotective potential of Solanum xanthocarpum (Solanaceae) (S. xanthocarpum) in experimental rats to validate its traditional claim. 50% ethanolic fruit extract of S. xanthocarpum (SXE, 100, 200 or 400 mg/kg body weight) was administered daily for 14 days in experimental animals. Liver injury was induced chemically, by CCl(4) administration (1 mL/kg i. p.). The hepatoprotective activity was assessed using various biochemical parameters like aspartate aminotransferase (AST), alanine aminotransferase (ALT), Serum alkaline phosphatise (SALP) and total bilirubin. Meanwhile, in vivo antioxidant activities as lipid peroxidation (LPO), reduced glutathione (GSH), superoxide dismutase (SOD) and catalase (CAT) were screened along with histopathological studies. Obtained results demonstrated that the treatment with SXE significantly (P<0.05-<0.001) and dose-dependently prevented chemically induced increase in serum levels of hepatic enzymes. Furthermore, SXE significantly (up to P<0.001) reduced the lipid peroxidation in the liver tissue and restored activities of defence antioxidant enzymes GSH, SOD and catalase towards normal levels. Histopathology of the liver tissue showed that SXE attenuated the hepatocellular necrosis and led to reduction of inflammatory cells inflltration. The results of this study strongly indicate the protective effect of SXE against acute liver injury which may be attributed to its hepatoprotective activity, and there by scientifically support its traditional use. Copyright © 2011 Hainan Medical College. Published by Elsevier B.V. All rights reserved.

  11. Symposium on Recent Advances in Experimental Mechanics : in honor of Isaac M. Daniel

    CERN Document Server

    2002-01-01

    This book contains 71 papers presented at the symposium on “Recent Advances in Experimental Mechanics” which was organized in honor of Professor Isaac M. Daniel. The symposium took place at Virginia Polytechnic Institute and State University on th June 23-28, 2002, in conjunction with the 14 US National Congress of Applied Mechanics. The book is a tribute to Isaac Daniel, a pioneer of experimental mechanics and composite materials, in recognition of his continuous, original, diversified and outstanding contributions for half a century. The book consists of invited papers written by leading experts in the field. It contains original contributions concerning the latest developments in experimental mechanics. It covers a wide range of subjects, including optical methods of stress analysis (photoelasticity, moiré, etc.), composite materials, sandwich construction, fracture mechanics, fatigue and damage, nondestructive evaluation, dynamic problems, fiber optic sensors, speckle metrology, digital image process...

  12. Development and Characterisation of a Human Chronic Skin Wound Cell Line-Towards an Alternative for Animal Experimentation.

    Science.gov (United States)

    Caley, Matthew; Wall, Ivan B; Peake, Matthew; Kipling, David; Giles, Peter; Thomas, David W; Stephens, Phil

    2018-03-27

    Background : Chronic skin wounds are a growing financial burden for healthcare providers, causing discomfort/immobility to patients. Whilst animal chronic wound models have been developed to allow for mechanistic studies and to develop/test potential therapies, such systems are not good representations of the human chronic wound state. As an alternative, human chronic wound fibroblasts (CWFs) have permitted an insight into the dysfunctional cellular mechanisms that are associated with these wounds. However, such cells strains have a limited replicative lifespan and therefore a limited reproducibility/usefulness. Objectives : To develop/characterise immortalised cell lines of CWF and patient-matched normal fibroblasts (NFs). Methods and Results : Immortalisation with human telomerase resulted in both CWF and NF proliferating well beyond their replicative senescence end-point (respective cell strains senesced as normal). Gene expression analysis demonstrated that, whilst proliferation-associated genes were up-regulated in the cell lines (as would be expected), the immortalisation process did not significantly affect the disease-specific genotype. Immortalised CWF (as compared to NF) also retained a distinct impairment in their wound repopulation potential (in line with CWF cell strains). Conclusions : These novel CWF cell lines are a credible animal alternative and could be a valuable research tool for understanding both the aetiology of chronic skin wounds and for therapeutic pre-screening.

  13. Development and Characterisation of a Human Chronic Skin Wound Cell Line—Towards an Alternative for Animal Experimentation

    Science.gov (United States)

    Wall, Ivan B.; Peake, Matthew; Kipling, David; Giles, Peter; Thomas, David W.

    2018-01-01

    Background: Chronic skin wounds are a growing financial burden for healthcare providers, causing discomfort/immobility to patients. Whilst animal chronic wound models have been developed to allow for mechanistic studies and to develop/test potential therapies, such systems are not good representations of the human chronic wound state. As an alternative, human chronic wound fibroblasts (CWFs) have permitted an insight into the dysfunctional cellular mechanisms that are associated with these wounds. However, such cells strains have a limited replicative lifespan and therefore a limited reproducibility/usefulness. Objectives: To develop/characterise immortalised cell lines of CWF and patient-matched normal fibroblasts (NFs). Methods and Results: Immortalisation with human telomerase resulted in both CWF and NF proliferating well beyond their replicative senescence end-point (respective cell strains senesced as normal). Gene expression analysis demonstrated that, whilst proliferation-associated genes were up-regulated in the cell lines (as would be expected), the immortalisation process did not significantly affect the disease-specific genotype. Immortalised CWF (as compared to NF) also retained a distinct impairment in their wound repopulation potential (in line with CWF cell strains). Conclusions: These novel CWF cell lines are a credible animal alternative and could be a valuable research tool for understanding both the aetiology of chronic skin wounds and for therapeutic pre-screening. PMID:29584680

  14. Enhancing search efficiency by means of a search filter for finding all studies on animal experimentation in PubMed.

    NARCIS (Netherlands)

    Hooijmans, C.R.; Tillema, A.; Leenaars, M.; Ritskes-Hoitinga, M.

    2010-01-01

    Collecting and analysing all available literature before starting an animal experiment is important and it is indispensable when writing a systematic review (SR) of animal research. Writing such review prevents unnecessary duplication of animal studies and thus unnecessary animal use (Reduction).

  15. An investigation to evaluate the analgesic and central nervous system depressant activities of Solanum nigrum (Linn. in Homoeopathic potencies in experimental animal models

    Directory of Open Access Journals (Sweden)

    Echur Natarajan Sundaram

    2015-01-01

    Full Text Available Background and Objective: In Homoeopathy, Solanum nigrum is clinically used in the treatment of ergotism, meningitis, irritation during dentition and some of the symptoms of neurological disorders but its Central Nervous System (CNS potential has not been explored experimentally yet. Therefore, a preliminary study was conducted with an objective to evaluate the analgesic and CNS depressant effects of homoeopathic potencies of S. nigrum in experimental animal models. Materials and Methods: The study was conducted in Wistar albino rats using a hot plate, ice plate and Randall-Selitto assay for analgesic; rota-rod and open field test for CNS depressant activities. The different potencies (3X, 6X, 12X and 30C of Solanum nigrum were administered orally (0.5 ml/rat/day for 30 days and response was assessed after 30 minutes of drug administration on 10 th , 20 th and 30 th day. Results: The result shows that all the four potencies of Solanum nigrum has increased the latency time required to raise and lick the paws for thermal sensation on hot plate test and for cold sensation on ice plate test and also increased the degree of threshold pressure to mechanically induced pain on Randall-Selitto assay but depressed the motor coordination and locomotor activities. Conclusion: The result obtained from this preliminary study suggests that homoeopathic preparation of Solanum nigrum in different potencies possess analgesic and CNS depressant activities. Further detailed investigations are required for its possible human use.

  16. Thermoradiotherapy in animal experimentation

    International Nuclear Information System (INIS)

    Dietzel, F.; Linhart, G.; Kovacs, G.; Giessen Univ.

    1978-01-01

    Solid Ehrlich carcinomas were transplanted to the neck of mice and, having reached 1 ml of volume, were irradiated with X-rays (150 kV) or treated with local high-frequency hyperthermia or with a combination of both the therapeutic techniques (thermoradiotherapy). Then, curves of tumor growth and of cure rates were ascertained. Tumor growth decreases following irradiation, whereas survival and cure rates are increasing with the doses delivered. The effect upon survival and cure rates seen after sole treatment with hyperthermia is of no importance, even if the heating was intensified. A more than additive, distinctly enhanced total effect, however, was observed following a combined treatment with graded heating and acute X-irradiation delivering a dose of 2000 R. This intensifying effect of hyperthermia appears already with low doses and is most marked with medium doses of hyperthermia. The sequence of the therapeutic components seems to be of no account if hyperthermia and X-irradiation immediately succeed one another. Values between 1.6 and 2.0 have been calculated for the thermal enhancement ratio (TER) within the optimal range of hyperthermia (41 to 42 0 C). The mortality due to the treatment is less than 1%. (orig.) [de

  17. Numerical and experimental characterization of ceramic pebble beds under cycling mechanical loading

    Energy Technology Data Exchange (ETDEWEB)

    Pupeschi, S., E-mail: pupeschi.simone@hotmail.it [Institute for Applied Materials, Karlsruhe Institute of Technology (KIT) (Germany); Knitter, R.; Kamlah, M. [Institute for Applied Materials, Karlsruhe Institute of Technology (KIT) (Germany); Gan, Y. [School of Civil Engineering, The University of Sydney, Sydney, NSW, 2006 (Australia)

    2016-11-15

    Highlights: • The effect of cyclic loading on the mechanical response of pebble beds was assessed. • Numerical simulations were performed with KIT-DEM code. • The numerical simulations were compared with the experimental outcomes. • A good qualitative agreement between experimental and simulation results was found. • The pebble size distribution affects the mechanical response of the assemblies. - Abstract: All solid breeder concepts considered to be tested in ITER (International Thermonuclear Experimental Reactor), make use of lithium-based ceramics in the form of pebble-packed beds as tritium breeder. A thorough understanding of the thermal and mechanical properties of the ceramic pebble beds under fusion relevant conditions is essential for the design of the breeder blanket modules of future fusion reactors. In this study, the effect of cyclic loading on the mechanical behaviour of pebble bed assemblies was investigated using a Discrete Element Method (DEM) code. The numerical simulations were compared with the experimental outcomes. The results of numerical simulations show that the pebble size distribution affects noticeably the stress-strain behaviour of the assemblies. A good qualitative agreement between experimental and simulation results was found in terms of difference between residual strains of consecutive cycles. An increase of the oedometric modulus with the compressive load was observed for all investigated compositions in both experimental and DEM simulations. The numerical results show an increase of the oedometric modulus (E) with progressive compaction of the assemblies due to the cycling loading, while no significant influence of the pebbles size distribution was observed.

  18. Favorable results from the use of herbal and plant products in inflammatory bowel disease: evidence from experimental animal studies

    Science.gov (United States)

    Triantafillidis, John K.; Triantafyllidi, Aikaterini; Vagianos, Constantinos; Papalois, Apostolos

    2016-01-01

    The use of herbal therapy for inflammatory bowel disease is increasing worldwide. The aim of this study was to review the available literature on the efficacy of herbal therapy in experimental colitis. All relevant studies published in Medline and Embase up to June 2015 have been reviewed. The results of bowel histology and serum parameters have been recorded. A satisfactory number of published experimental studies, and a quite large one of both herbal and plant products tested in different studies have been reported. The results showed that in the majority of the studies, herbal therapy reduced the inflammatory activity of experimental colitis and diminished the levels of many inflammatory indices, including serum cytokines and indices of oxidative stress. The most promising plant and herbal products were tormentil extracts, wormwoodherb, Aloe vera, germinated barley foodstuff, curcumin, Boswellia serrata, Panax notoginseng, Ixeris dentata, green tea, Cordia dichotoma, Plantago lanceolata, Iridoidglycosides, and mastic gum. Herbal therapies exert their therapeutic benefit via various mechanisms, including immune regulation, anti-oxidant activity, inhibition of leukotriene B4 and nuclear factor-κB, and antiplatelet activity. Large, double-blind clinical studies assessing these natural substances should be urgently conducted. PMID:27366027

  19. Dynamicimagestoaddressconceptualnodes about mechanical waves: Example materials and preliminary results of the experimentation of the teacher training module IMAGONDE

    Science.gov (United States)

    Testa, I.; Lombardi, S.; Monroy, G.; Sassi, E.

    2004-09-01

    In the framework of the 2002-03 project “Fisica per la Formazione Culturale - FORMazione Insegnanti" funded by Italy ministry of Education, a set of training materials, focused on mechanical waves, has been developed. The core of the materials is represented by animated images purposely designed in order to: 1) address intrinsically dynamic aspects of one-dimensional impulses/waves propagation on a string; 2) have the trainees reflect upon students' difficulties in reading/interpreting static images (as the ones which are featured in common textbooks) and animations. In this paper we discuss example materials concerning transversal impulses on strings to address conceptual nodes such as: 1) configuration of the string at a given time and its aaabstract representation; 2) displacement vs. time graph of a string element and its aaabstract representation; 3) relationships between the two aaabstract representations; 4) modelization of mechanical wave propagation in one dimension. Moreover the results of the experimentation of the training materials in the framework of the Post Graduate School to Became Physics Teacher in Secondary Schools are presented and commented.

  20. Initial study of sediment antagonism and characteristics of silver nanoparticle-coated biliary stents in an experimental animal model

    Directory of Open Access Journals (Sweden)

    Tian Y

    2016-04-01

    Full Text Available Yigeng Tian,1,* Mingfeng Xia,2,* Shuai Zhang,3 Zhen Fu,4 Qingbin Wen,2 Feng Liu,4 Zongzhen Xu,4 Tao Li,4 Hu Tian4 1Department of Physics, School of Physics and Technology, University of Jinan, Jinan, Shandong, People’s Republic of China; 2Department of Surgery, Shandong University of Traditional Chinese Medicine, Jinan, Shandong, People’s Republic of China; 3Department of General Surgery, Sixth People’s Hospital of Jinan, Jinan, Shandong, People’s Republic of China; 4Department of General Surgery, Shandong Provincial Qianfoshan Hospital, Shandong University, Jinan, Shandong, People’s Republic of China *These authors contributed equally to this work Objective: Plastic biliary stents used to relieve obstructive jaundice are frequently blocked by sediment, resulting in loss of drainage. We prepared stents coated with silver nanoparticles (AgNPs and compared their ability to resist sedimentation with Teflon stents in a beagle model of obstructive jaundice.Methods: AgNP-coated Teflon biliary stents were prepared by chemical oxidation–reduction and evaluated in an obstructive jaundice model that was produced by ligation of common bile duct (CBD; animals were randomized to two equal groups for placement of AgNP-coated or Teflon control stents. Liver function and inflammatory index were found to be similar in the two groups, and the obstruction was relieved. Stents were removed 21 days after insertion and observed by scanning and transmission electron microscopy. The AgNP coating was analyzed by energy dispersive X-ray analysis (EDXA, and the composition of sediment was assayed by Fourier-transform infrared (FTIR spectroscopy.Results: Electron microscopy revealed a black, closely adherent AgNP stent coating, with thicknesses of 1.5–6 µm. Sediment thickness and density were greater on Teflon than on AgNP-coated stents. EDXA confirmed the stability and integrity of the AgNP coating before and after in vivo animal experimentation. FTIR

  1. Signaling in a polluted world: oxidative stress as an overlooked mechanism linking contaminants to animal communication

    OpenAIRE

    Valeria Marasco; David Costantini; David Costantini

    2016-01-01

    The capacity to communicate effectively with other individuals plays a critical role in the daily life of an individual and can have important fitness consequences. Animals rely on a number of visual and non-visual signals, whose production brings costs to the individual. The theory of honest signaling states that these costs are higher for low than for high-quality individuals, which prevents cheating and makes signals, such as skin and plumage colouration, indicators of individual’s quality...

  2. Signaling in a Polluted World: Oxidative Stress as an Overlooked Mechanism Linking Contaminants to Animal Communication

    OpenAIRE

    Marasco, Valeria; Costantini, David

    2016-01-01

    The capacity to communicate effectively with other individuals plays a critical role in the daily life of an individual and can have important fitness consequences. Animals rely on a number of visual and non-visual signals, whose production brings costs to the individual. The theory of honest signaling states that these costs are higher for low than for high-quality individuals, which prevents cheating and makes signals, such as skin and plumage coloration, indicators of individual's quality ...

  3. Health Status of Male Adult Wistar Rats from Two Experimental Animal Houses of UFMG: Leukocyte Counts, Feces and Lung Histological Exams

    Directory of Open Access Journals (Sweden)

    Andrade Bruno Horta

    2002-01-01

    Full Text Available A study was conducted to compare health status of male adult Wistar rats from two Experimental Animal Houses of UFMG with literature data of SPF (free from specific pathogens and conventional rats. The animals were divided into two groups: Group I (n=10, rats from the experimental animal houses of FAFICH and Group II (n=10 from ICB and following aspects were studied: a evident clinical signs (behavior modification, hair loss (alopecia, b leukocyte counts, c feces exam and d histological study of the lungs. The rats did not show clinical signs. However, when compared with SPF and conventional rats, both the groups showed a significant increase (p<0,05 of leukocyte count. On feces exam we detected some parasites and on lung histological exam we observed fungus (Group I and bacteria (Group II. These results showed that the health status of the rats was not satisfactory and required improvements in the conditions of the animal houses.

  4. Quantum Mechanics and locality in the K0 K-bar0 system experimental verification possibilities

    International Nuclear Information System (INIS)

    Muller, A.

    1994-11-01

    It is shown that elementary Quantum Mechanics, applied to the K 0 K-bar 0 system, predicts peculiar long range EPR correlations. Possible experimental verifications are discussed, and a concrete experiment with anti-protons annihilations at rest is proposed. A pedestrian approach to local models shows that K 0 K-bar 0 experimentation could provide arguments to the local realism versus quantum theory controversy. (author). 17 refs., 23 figs

  5. micro-mechanical experimental investigation and modelling of strain and damage of argillaceous rocks under combined hydric and mechanical loads

    International Nuclear Information System (INIS)

    Wang, L.

    2012-01-01

    The hydro-mechanical behavior of argillaceous rocks, which are possible host rocks for underground radioactive nuclear waste storage, is investigated by means of micro-mechanical experimental investigations and modellings. Strain fields at the micrometric scale of the composite structure of this rock, are measured by the combination of environmental scanning electron microscopy, in situ testing and digital image correlation technique. The evolution of argillaceous rocks under pure hydric loading is first investigated. The strain field is strongly heterogeneous and manifests anisotropy. The observed nonlinear deformation at high relative humidity (RH) is related not only to damage, but also to the nonlinear swelling of the clay mineral itself, controlled by different local mechanisms depending on RH. Irreversible deformations are observed during hydric cycles, as well as a network of microcracks located in the bulk of the clay matrix and/or at the inclusion-matrix interface. Second, the local deformation field of the material under combined hydric and mechanical loadings is quantified. Three types of deformation bands are evidenced under mechanical loading, either normal to stress direction (compaction), parallel (microcracking) or inclined (shear). Moreover, they are strongly controlled by the water content of the material: shear bands are in particular prone to appear at high RH states. In view of understanding the mechanical interactions a local scale, the material is modeled as a composite made of non-swelling elastic inclusions embedded in an elastic swelling clay matrix. The internal stress field induced by swelling strain incompatibilities between inclusions and matrix, as well as the overall deformation, is numerically computed at equilibrium but also during the transient stage associated with a moisture gradient. An analytical micro-mechanical model based on Eshelby's solution is proposed. In addition, 2D finite element computations are performed. Results

  6. Comparative experimental studies into radioimmunoscintigraphy using radioactive antibodies in animals with HeLa cell carcinomas and Yoshida sarcomas

    International Nuclear Information System (INIS)

    Zettl, T.

    1988-01-01

    TPA-positive and TPA-negative tumour-bearing animal systems (HeLa cell carcinomas in RNU rats and Yoshida sarcomas in Wistar rats) were examined to show that the method of scanning can well be used to visualise tumour tissue. In this connection, further attempts were made to shed light on the specifity of immunoscintigraphy in the search for tumour tissue. 125-Iodine-anti-TPA was found to be a specific carcinoma-seeking substance. The amount of antibodies accumulating in the tumour was multiplied by previous intravenous treatment of test animals with unspecific immunoglobulin. In control studies using 125-iodine-immunoglobulin the site of the carcinomatous tissue could not be determined with sufficient diagnostic accuracy. It was found that the discriminating power of radioimmunoscintigraphy using 125-iodine-anti-TPA is quite unrelated to an increased circulation in the proliferating carcinomatous tissue. For the detection of TPA in HeLa cell carcinomas anti-TPA PAP stains were prepared. Radionuclide studies using 125-iodine-anti-TPA were also useful in the visualisation of the Yoshida sarcoma, even though this scores negative on TPA. Here, the amounts of radioactivity accumulating in the tumour were smaller than with the HeLa cell carcinoma. Moreover, peak levels were measured after no less than one day, as compared to the five days required for HeLa cell tumours to reach maximum levels. This finding would appear to provide presumptive evidence that there are other, unspecific mechanisms of tumour selectivity. (orig/MG) [de

  7. Seizures triggered by food intake in antimuscarinic-treated fasted animals: evaluation of the experimental findings in terms of similarities to eating-triggered epilepsy.

    Science.gov (United States)

    Enginar, Nurhan; Nurten, Asiye

    2010-07-01

    Food intake triggers convulsions in fasted mice and rats treated with antimuscarinic drugs, scopolamine or atropine. Bearing some similarities in triggering factor and manifestations of the seizures in patients with eating-evoked epilepsy, seizures in fasted animals may provide insight into the mechanism(s) of this rare and partially controlled form of reflex epilepsy.

  8. Labelling study of galacturonic acid with Tc-99m and investigation of the biokinetic behaviour in experimental animals

    International Nuclear Information System (INIS)

    1988-01-01

    The main criterion in the selection of a proper ligand to be labelled with Technetium is to match the requirement of a radiopharmaceutical of good biological specificity, where the target organ-to-background ratio is considerably high. Perliminary study on experimental animals has shown, that galacturonic acid is among those ligands of high renal specificity after complexing with Tc-99. In this communication we describe for the first time the labelling of galacturonic acid with Tc-99, using stannous chloride as a reducing agent for pertechnetate. The radioanalytical results assessed by gelchromatography column scanning (GCS) method, reveal that, the labelling efficiency of (Tc)99-galacturonate complex is promoted by raising the pH of the reaction mixture to a value higher than 7 using tris (hydroxymethyl) aminomethane buffer. The optimal amounts of the reactants to obtain a high labelled and stable complex with high kidney uptake, were found to be not less than 50 mg galacturonic acid and not more than 200 Mg SnCl2.H2O in the preparation

  9. Experimental study on oral sulfhydryl as an adjuvant for improving nitrate ester tolerance in an animal model.

    Science.gov (United States)

    Chen, L; Jiang, J-Q; Zhang, Y; Feng, H

    2018-03-01

    As an initial step in exploring the feasibility of oral sulfhydryl as an adjuvant for improving nitrate ester tolerance, this study was designed to experimentally test the adjuvant therapy in a rabbit model of atherosclerosis (AS). New Zealand white rabbits with induced AS were randomly divided into four groups: AS group, AS + nitrate ester group, AS + nitrate ester tolerance group, and AS + drug combination group. Additionally, four equivalent groups with healthy New Zealand white rabbits without AS were also conformed. After feeding the animals for 5 days, the concentrations of superoxide anion (•O2-), superoxide dismutase (SOD), malondialdehyde (MDA), nitric oxide (NO), and endothelin-1 (ET-1) in blood and the relaxation response of the aortic ring were determined in each subject. The vascular plaques in different treatment groups were assessed by Hematoxylin and eosin (HE) staining to investigate the therapeutic value of sulfhydryl as coadjuvant for improving nitrate ester tolerance, and changes in blood vessels in different treatment groups were studied by immunohistochemical assays. Our results showed no significant differences through time in the concentrations of •O2-, SOD, MDA, NO, ET-1 between the healthy control and the nitrate ester groups (p > 0.05). The levels of SOD and MDA in the nitrate ester tolerance group increased with time, however, the levels of •O2-, NO and ET-1 decreased gradually (p tolerance groups were significantly decreased, but SOD and MDA were significantly increased (p tolerance, and this strategy was safe and looks promising for humans.

  10. Research ethics I: Responsible conduct of research (RCR)--historical and contemporary issues pertaining to human and animal experimentation.

    Science.gov (United States)

    Horner, Jennifer; Minifie, Fred D

    2011-02-01

    In this series of articles--Research Ethics I, Research Ethics II, and Research Ethics III--the authors provide a comprehensive review of the 9 core domains for the responsible conduct of research (RCR) as articulated by the Office of Research Integrity. In Research Ethics I, they present a historical overview of the evolution of RCR in the United States then examine the evolution of human and animal experimentation from the birth of scientific medicine through World War II to the present day. They relied on authoritative documents, both historical and contemporary, insightful commentary, and empirical research in order to identify current issues and controversies of potential interest to both faculty and students. The authors have written this article from a historical perspective because they think all readers interested in RCR should appreciate how the history of science and all the good--and harm--it has produced can inform how researchers practice responsible research in the 21st century and beyond.

  11. Experimental MRI-SPECT insert system with Hybrid Semiconductor detectors Timepix for MR animal scanner Bruker 47/20

    Science.gov (United States)

    Zajicek, J.; Burian, M.; Soukup, P.; Novak, V.; Macko, M.; Jakubek, J.

    2017-01-01

    Multimodal medical imaging based on Magnetic Resonance is mainly combinated with one of the scintigraphic method like PET or SPECT. These methods provide functional information whereas magnetic resonance imaging provides high spatial resolution of anatomical information or complementary functional information. Fusion of imaging modalities allows researchers to obtain complimentary information in a single measurement. The combination of MRI with SPECT is still relatively new and challenging in many ways. The main complication of using SPECT in MRI systems is the presence of a high magnetic field therefore (ferro)magnetic materials have to be eliminated. Furthermore the application of radiofrequency fields within the MR gantry does not allow for the use of conductive structures such as the common heavy metal collimators. This work presents design and construction of an experimental MRI-SPECT insert system and its initial tests. This unique insert system consists of an MR-compatible SPECT setup with CdTe pixelated sensors Timepix tungsten collimators and a radiofrequency coil. Measurements were performed on a gelatine and tissue phantom with an embedded radioisotopic source (57Co 122 keV γ ray) inside the RF coil by the Bruker BioSpec 47/20 (4.7 T) MR animal scanner. The project was performed in the framework of the Medipix Collaboration.

  12. Chemistry, Antimicrobial Mechanisms, and Antibiotic Activities of Cinnamaldehyde against Pathogenic Bacteria in Animal Feeds and Human Foods.

    Science.gov (United States)

    Friedman, Mendel

    2017-12-06

    Cinnamaldehyde is a major constituent of cinnamon essential oils produced by aromatic cinnamon plants. This compound has been reported to exhibit antimicrobial properties in vitro in laboratory media and in animal feeds and human foods contaminated with disease-causing bacteria including Bacillus cereus, Campylobacter jejuni, Clostridium perfringens, Escherichia coli, Listeria monocytogenes, and Salmonella enterica. This integrated review surveys and interprets our current knowledge of the chemistry, analysis, safety, mechanism of action, and antibiotic activities of cinnamaldehyde in food animal (cattle, lambs, calves, pigs, poultry) diets and in widely consumed liquid (apple, carrot, tomato, and watermelon juices, milk) and solid foods. Solid foods include various fruits (bayberries, blueberries, raspberries, and strawberries), vegetables (carrots, celery, lettuce, spinach, cucumbers, and tomatoes), meats (beef, ham, pork, and frankfurters), poultry (chickens and turkeys), seafood (oysters and shrimp), bread, cheese, eggs, infant formula, and peanut paste. The described findings are not only of fundamental interest but also have practical implications for food safety, nutrition, and animal and human health. The collated information and suggested research needs will hopefully facilitate and guide further studies needed to optimize the use of cinnamaldehyde alone and in combination with other natural antimicrobials and medicinal antibiotics to help prevent and treat food animal and human diseases.

  13. An experimental study of mechanical behavior of natural fiber reinforced polymer matrix composites

    Science.gov (United States)

    Ratna, Sanatan; Misra, Sheelam

    2018-05-01

    Fibre-reinforced polymer composites have played a dominant role for a long time in a variety of applications for their high specific strength and modulus. The fibre which serves as a reinforcement in reinforced plastics may be synthetic or natural. Past studies show that only synthetic fibres such as glass, carbon etc., have been used in fibre reinforced plastics. Although glass and other synthetic fibre-reinforced plastics possess high specific strength, their fields of application are very limited because of their inherent higher cost of production. In this connection, an investigation has been carried out to make use of horse hair, an animal fibre abundantly available in India. Animal fibres are not only strong and lightweight but also relatively very cheaper than mineral fibre. The present work describes the development and characterization of a new set of animal fiber based polymer composites consisting of horse hair as reinforcement and epoxy resin. The newly developed composites are characterized with respect to their mechanical characteristics. Experiments are carried out to study the effect of fibre length on mechanical behavior of these epoxy based polymer composites. Composite made form horse hair can be used as a potential reinforcing material for many structural and non-structural applications. This work can be further extended to study other aspects of such composites like effect of fiber content, loading pattern, fibre treatment on mechanical behavior of horse hair based polymer horse hair.

  14. Experimental research on the residual mechanical properties of an ordinary concretes after fire

    OpenAIRE

    Santos, C.C.; Rodrigues, J.P.

    2015-01-01

    This paper summarizes the results of an experimental research to assess the residual mechanical properties of an ordinary concrete after fire. It was studied the influence of the cooling process, the maximum temperature that the concrete was subjected to and the loading level on the residual mechanical properties of calcareous and granite aggregate concretes. The properties studied were the residual compressive, tensile, splitting and flexural strengths and modulus of elasticit...

  15. Resveratrol and endometriosis: In vitro and animal studies and underlying mechanisms (Review).

    Science.gov (United States)

    Kolahdouz Mohammadi, Roya; Arablou, Tahereh

    2017-07-01

    Endometriosis is characterized by the existence of endometrial tissue and stroma exterior to the uterus. Despite the high prevalence, the etiology of endometriosis remains elusive. The search for the most promising compounds for treatment of endometriosis has led to the identification of resveratrol. Resveratrol, a plant-derived polyphenolic phytoalexin, demonstrates broad-spectrum health beneficial effects, including anti-proliferative, anti-inflammatory, antineoplastic and antioxidant. Because of these properties and its wide distribution in plants, resveratrol is proposed as a great potential to treat endometriosis. In animal models of endometriosis, resveratrol supplementation has displayed beneficial results as it decreased the number and volume of endometrial implants, suppressed proliferation, vascularization, inflammation, cell survival and increased apoptosis. On the other hand, resveratrol treatment in-vitro studies, reduced invasiveness of endometriotic stromal cells (ESCs) and suppressed their inflammatory responses. In this review, we will summarize the recent studies in in-vitro and animal studies on resveratrol and endometriosis. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

  16. An Examination of Drag Reduction Mechanisms in Marine Animals, with Potential Applications to Uninhabited Aerial Vehicles

    Science.gov (United States)

    Musick, John A.; Patterson, Mark R.; Dowd, Wesley W.

    2002-01-01

    Previous engineering research and development has documented the plausibility of applying biomimetic approaches to aerospace engineering. Past cooperation between the Virginia Institute of Marine Science (VIMS) and NASA focused on the drag reduction qualities of the microscale dermal denticles of shark skin. This technology has subsequently been applied to submarines and aircraft. The present study aims to identify and document the three-dimensional geometry of additional macroscale morphologies that potentially confer drag reducing hydrodynamic qualities upon marine animals and which could be applied to enhance the range and endurance of Uninhabited Aerial Vehicles (UAVs). Such morphologies have evolved over eons to maximize organismal energetic efficiency by reducing the energetic input required to maintain cruising speeds in the viscous marine environment. These drag reduction qualities are manifested in several groups of active marine animals commonly encountered by ongoing VIMS research programs: namely sharks, bony fishes such as tunas, and sea turtles. Through spatial data acquired by molding and digital imagery analysis of marine specimens provided by VIMS, NASA aims to construct scale models of these features and to test these potential drag reduction morphologies for application to aircraft design. This report addresses the efforts of VIMS and NASA personnel on this project between January and November 2001.

  17. Neural mechanisms regulating different forms of risk-related decision-making: Insights from animal models.

    Science.gov (United States)

    Orsini, Caitlin A; Moorman, David E; Young, Jared W; Setlow, Barry; Floresco, Stan B

    2015-11-01

    Over the past 20 years there has been a growing interest in the neural underpinnings of cost/benefit decision-making. Recent studies with animal models have made considerable advances in our understanding of how different prefrontal, striatal, limbic and monoaminergic circuits interact to promote efficient risk/reward decision-making, and how dysfunction in these circuits underlies aberrant decision-making observed in numerous psychiatric disorders. This review will highlight recent findings from studies exploring these questions using a variety of behavioral assays, as well as molecular, pharmacological, neurophysiological, and translational approaches. We begin with a discussion of how neural systems related to decision subcomponents may interact to generate more complex decisions involving risk and uncertainty. This is followed by an overview of interactions between prefrontal-amygdala-dopamine and habenular circuits in regulating choice between certain and uncertain rewards and how different modes of dopamine transmission may contribute to these processes. These data will be compared with results from other studies investigating the contribution of some of these systems to guiding decision-making related to rewards vs. punishment. Lastly, we provide a brief summary of impairments in risk-related decision-making associated with psychiatric disorders, highlighting recent translational studies in laboratory animals. Copyright © 2015 Elsevier Ltd. All rights reserved.

  18. Chapel Hill bisphenol A expert panel consensus statement: Integration of mechanisms, effects in animals and potential to impact human health at current levels of exposure

    Science.gov (United States)

    vom Saal, Frederick S.; Akingbemi, Benson T.; Belcher, Scott M.; Birnbaum, Linda S.; Crain, D. Andrew; Eriksen, Marcus; Farabollini, Francesca; Guillette, Louis J.; Hauser, Russ; Heindel, Jerrold J.; Ho, Shuk-Mei; Hunt, Patricia A.; Iguchi, Taisen; Jobling, Susan; Kanno, Jun; Keri, Ruth A.; Knudsen, Karen E.; Laufer, Hans; LeBlanc, Gerald A.; Marcus, Michele; McLachlan, John A.; Myers, John Peterson; Nadal, Angel; Newbold, Retha R.; Olea, Nicolas; Prins, Gail S.; Richter, Catherine A.; Rubin, Beverly S.; Sonnenschein, Carlos; Soto, Ana M.; Talsness, Chris E.; Vandenbergh, John G.; Vanderberg, Laura N.; Walser-Kuntz, Debby R.; Watson, Cheryl S.; Welshons, Wade V.; Wetherill, Yelena; Zoeller, R. Thomas

    2007-01-01

    This document is a summary statement of the outcome from the meeting: “Bisphenol A: An Examination of the Relevance of Ecological, In vitro and Laboratory Animal Studies for Assessing Risks to Human Health” sponsored by both the NIEHS and NIDCR at NIH/DHHS, as well as the US-EPA and Commonweal on the estrogenic environmental chemical bisphenol A (BPA, 2,2-bis(4-hydroxyphenyl)propane; CAS# 80-05-7). The meeting was held in Chapel Hill, NC, 28–30 November 2006 due to concerns about the potential for a relationship between BPA and negative trends in human health that have occurred in recent decades. Examples include increases in abnormal penile/urethra development in males, early sexual maturation in females, an increase in neurobehavioral problems such as attention deficit hyperactivity disorder (ADHD) and autism, an increase in childhood and adult obesity and type 2 diabetes, a regional decrease in sperm count, and an increase in hormonally mediated cancers, such as prostate and breast cancers. Concern has been elevated by published studies reporting a relationship between treatment with “low doses” of BPA and many of theses negative health outcomes in experimental studies in laboratory animals as well as in vitro studies identifying plausible molecular mechanisms that could mediate such effects. Importantly, much evidence suggests that these adverse effects are occurring in animals within the range of exposure to BPA of the typical human living in a developed country, where virtually everyone has measurable blood, tissue and urine levels of BPA that exceed the levels produced by doses used in the “low dose” animal experiments.

  19. Experimental and numerical study of the micro-mechanical failure in composites

    DEFF Research Database (Denmark)

    Ashouri Vajari, Danial; Martyniuk, Karolina; Sørensen, Bent F.

    2013-01-01

    The fibre/matrix interfacial debonding is found to be the first microscale failure mechanism leading to subsequent macroscale transverse cracks in composite materials under tensile load. In this paper, the micromechanical interface failure in fiber-reinforced composites is studied experimentally ...

  20. Early age mechanical behaviour of 3D printed concrete : Numerical modelling and experimental testing

    NARCIS (Netherlands)

    Wolfs, R.J.M.; Bos, F.P.; Salet, T.A.M.

    2018-01-01

    A numerical model was developed to analyse the mechanical behaviour of fresh, 3D printed concrete, in the range of 0 to 90 min after material deposition. The model was based on a time-dependent Mohr-Coulomb failure criterion and linear stress-strain behaviour up to failure. An experimental program,

  1. Experimental study on the scram of electromagnetic movable coil control rod drive mechanism

    International Nuclear Information System (INIS)

    Sun Changlong; Bo Hanliang; Jiang Shengyao; Zhang Hongchao; Ma Cang; Wang Jinhua; Qin Benke

    2006-01-01

    Electromagnetic movable coil control rod drive mechanism is a new type drive mechanism. The drive mechanism is experimentally studied to gain the characteristic of scram time. Further more, the reason of the different scram phenomena is analyzed and the disciplinarian of scram is also summarized. On the base of series experiments it can be concluded that scram time of AC break is longer than that of DC break and the residual current of coil's can distinctly influence the scram time. The scram time of AC break is 300-700 ms longer than that of DC break. (authors)

  2. Theoretical and experimental determination of mechanical properties of superconducting composite wire

    International Nuclear Information System (INIS)

    Gray, W.H.; Sun, C.T.

    1976-07-01

    The mechanical properties of a composite superconducting (NbTi/Cu) wire are characterized in terms of the mechanical properties of each constituent material. For a particular composite superconducting wire, five elastic material constants were experimentally determined and theoretically calculated. Since the Poisson's ratios for the fiber and the matrix material were very close, there was essentially no (less than 1 percent) difference among all the theoretical predictions for any individual mechanical constant. Because of the expense and difficulty of producing elastic constant data of 0.1 percent accuracy, and therefore conclusively determining which theory is best, no further experiments were performed

  3. Experimental study and constitutive modeling of the viscoelastic mechanical properties of the human prolapsed vaginal tissue.

    Science.gov (United States)

    Peña, Estefania; Calvo, B; Martínez, M A; Martins, P; Mascarenhas, T; Jorge, R M N; Ferreira, A; Doblaré, M

    2010-02-01

    In this paper, the viscoelastic mechanical properties of vaginal tissue are investigated. Using previous results of the authors on the mechanical properties of biological soft tissues and newly experimental data from uniaxial tension tests, a new model for the viscoelastic mechanical properties of the human vaginal tissue is proposed. The structural model seems to be sufficiently accurate to guarantee its application to prediction of reliable stress distributions, and is suitable for finite element computations. The obtained results may be helpful in the design of surgical procedures with autologous tissue or prostheses.

  4. Experimental study and modelling of the high temperature mechanical behavior of oxide dispersion strengthened ferritic steels

    International Nuclear Information System (INIS)

    Steckmeyer, A.

    2012-01-01

    The strength of metals, and therefore their maximum operating temperature, can be improved by oxide dispersion strengthening (ODS). Numerous research studies are carried out at the French Atomic Energy Commission (CEA) in order to develop a cladding tube material for Gen IV nuclear power reactors. Oxide dispersion strengthened steels appear to be the most promising candidates for such application, which demands a minimum operating temperature of 650 C. The present dissertation intends to improve the understanding of the mechanical properties of ODS steels, in terms of creep lifetime and mechanical anisotropy. The methodology of this work includes mechanical tests between room temperature and 900 C as well as macroscopic and polycrystalline modelling. These tests are carried out on a Fe-14Cr1W0,26Ti + 0,3 Y 2 O 3 ODS ferritic steel processed at CEA by mechanical alloying and hot extrusion. The as-received material is a bar with a circular section. The mechanical tests reveal the high mechanical strength of this steel at high temperature. A strong influence of the strain rate on the ductility and the mechanical strength is also observed. A macroscopic mechanical model has been developed on the basis of some experimental statements such as the high kinematic contribution to the flow stress. This model has a strong ability to reproduce the mechanical behaviour of the studied material. Two different polycrystalline models have also been developed in order to reproduce the mechanical anisotropy of the material. They are based on its specific grain morphology and crystallographic texture. The discrepancy between the predictions of both models and experimental results reveal the necessity to formulate alternate assumptions on the deformation mechanisms of ODS ferritic steels. (author) [fr

  5. Mechanisms of quinolone resistance and implications for human and animal health

    Directory of Open Access Journals (Sweden)

    Velhner Maja

    2010-01-01

    Full Text Available Quinolone antibiotics have been widely used in human and veterinary medicine. This has caused the development of resistance and difficulties in the treatment of complicated bacterial infections in humans. The resistance to quinolones develops due to chromosome mutations and it can also be transferred by plasmids. The target enzyme for quinolones in Gram-negative bacteria is Gyrasa A, while the target enzyme in Grampositive bacteria is mostly topoisomerase IV. Gyrase A consists of two subunits encoded by genes gyrA and gyrB. The function of the enzyme is to introduce negative super coiling in DNA and therefore is essential for the replication of bacteria. Quinolone resistance develops if point mutations at 83 and/or 87 codon are introduced on gyrA. Establishing a minimal inhibitory concentration (MIC to this group of antimicrobials will reveal possible mutations. Recently it was discovered that quinolone resistance is transmittable by plasmid termed PMQR (plasmid mediated quinolone resistance. The target gene marked qnr encodes a pentapeptide repeat family protein. Pentapeptide repeats form sheets, involved in protein-protein interactions. Qnr protein binds to GyrA protecting the enzyme from the inhibitory effect of ciprofloxacin. The distribution of qnr related resistance is higher in humans than in animals. In poultry, however, this type of resistance is present more than in other animals. Plasmid mediated resistance contributes to the faster spread of quinolone resistance. Proper food handling will significantly contribute to decreasing the risk from infection to which people are exposed. In medical and veterinary laboratories antimicrobial resistance monitoring in clinical and environmental isolates is advised. Since correlation between antibiotics application and antimicrobial resistance is often suggested, antimicrobial use must be under strict control of the authorities both in human and in veterinary medicine. .

  6. Genetic resistance in experimental autoimmune encephalomyelitis. I. Analysis of the mechanism of LeR resistance using radiation chimeras

    International Nuclear Information System (INIS)

    Pelfrey, C.M.; Waxman, F.J.; Whitacre, C.C.

    1989-01-01

    Experimental autoimmune encephalomyelitis (EAE) is a cell-mediated autoimmune disease of the central nervous system that has been extensively studied in the rat. The Lewis rat is highly susceptible to the induction of EAE, while the Lewis resistant (LeR) rat is known to be resistant. In this paper, we demonstrate that the LeR rat, which was derived from the Lewis strain by inbreeding of fully resistant animals, is histocompatible with the Lewis strain. Radiation chimeras, a tool for distinguishing between immunologic and nonimmunologic resistance mechanisms, were utilized to analyze the cellular mechanisms involved in genetic resistance to EAE. By transplanting bone marrow cells from LeR rats into irradiated Lewis recipients, Lewis rats were rendered resistant to EAE induction. Likewise, transplanting Lewis bone marrow cells into irradiated LeR recipients rendered LeR rats susceptible. Mixed lymphoid cell chimeras using bone marrow, spleen, and thymus cells in Lewis recipient rats revealed individual lymphoid cell types and cell interactions that significantly affected the incidence and severity of EAE. Our results suggest that LeR resistance is mediated by hematopoietic/immune cells, and that cells located in the spleen appear to play a critical role in the resistance/susceptibility to EAE induction. Depletion of splenic adherent cells did not change the patterns of EAE resistance. In vivo cell mixing studies suggested the presence of a suppressor cell population in the LeR spleen preparations which exerted an inhibitory effect on Lewis autoimmune responses. Thus, the mechanism of LeR resistance appears to be different from that in other EAE-resistant animals

  7. Possible analgesic effect of vigabatrin in animal experimental chronic neuropathic pain Possível efeito analgésico da vigabatrina na dor neuropática crônica experimental animal

    Directory of Open Access Journals (Sweden)

    NILZA D. ALVES

    1999-12-01

    Full Text Available Since anticonvulsants have been used for treating neuralgias, an interest has arisen to experimentally test vigabatrin for its gabaergic mechanism of action. For this, 41 Wistar rats were used, and in 25 of them a constrictive sciatic neuropathy was induced (Bennet & Xie model. For testing pain symptoms, spontaneous (scratching and evoked behaviors to noxious (46o C and non-noxious (40o C thermal stimuli were quantified. Moreover, a comparative pharmacological study of vigabatrin with other analgesic anticonvulsant drugs was also performed. The results showed a possible dose-dependent analgesic effect of vigabatrin (gamma-vinyl-GABA on experimental neuropathic pain, as shown by the significant (pO uso de anticonvulsivantes no tratamento de neuralgias despertou um interesse em testar novas drogas anticonvulsivantes, e dentre essas a vigabatrina por possuir mecanismo de ação gabaérgico. Para isso, foram usados 41 ratos Wistar e em 25 deles induziu-se neuropatia ciática constritiva (modelo de Bennett & Xie. Para testar sintomas de dor, foram quantificados comportamentos espontâneos (coçar-se e evocados, por meio de estímulos térmicos nocivos (46oC e não-nocivos (40oC. Além disso, realizou-se estudo comparativo da vigabatrina com outros anticonvulsivantes analgésicos. Os resultados mostraram um possível efeito analgésico, dose-dependente, de vigabatrina (gama-vinil-GABA em dor neuropática experimental. Isso foi evidenciado pela diminuição significativa (p<0,05 do comportamento de coçar-se e pelo aumento significativo (p<0,05 da latência de retirada da pata posterior direita a estímulos térmicos nocivos. Isso foi corroborado por achados semelhantes em experimentos com anticonvulsivantes (carbamazepina, fenitoína e ácido valpróico analgésicos. Esse possível efeito analgésico da vigabatrina (ainda não descrito na literatura não é mediado pelo sistema opióide.

  8. Preface to special issue of selected papers from Theoretical, Experimental, and Computational Mechanics (TECM)

    DEFF Research Database (Denmark)

    Jabbari, Masoud; Sarlak Chivaee, Hamid; Hattel, Jesper Henri

    2017-01-01

    We are pleased to introduce this special issue of the Applied Mathematical Modelling journal with highlights from theTheoretical, Experimental, and Computational Mechanics Symposium (TECM-2015). This special issue consists of four rigorouslyselected papers originally presented at TECM-2015...... as a part of the 13th International Conference of Numerical Analysisand Applied Mathematics 2015 (ICNAAM 2015), which was held on 23-29 September 2015 in Rhodes, Greece.The symposium attracted a broad range of international and local leaders in theoretical, experimental, and computational mechanics across...... various fields and application. The symposium did an excellent job of outlining the current landscape of computational mechanics and its capabilities in solving complex industrial problems in the process industries, and we agree with the editor-in-chief of the journal that it is certainly worthwhile...

  9. Fundamental steps in experimental design for animal studies Passos fundamentais em desenhos experimentais de estudos envolvendo animais

    Directory of Open Access Journals (Sweden)

    José Eduardo de Aguilar-Nascimento

    2005-02-01

    Full Text Available Animal studies continue to have a vital role in science development. The aim of this review is to provide to new investigators an overview of the important steps involved in experimental designs and also to suggest some practical information that is commonly associated with this process. Investigators should adhere to the ethical procedure and follow strictly the scientific method. Both the aims and well-formulated hypothesis are essential and practical. In this regard a profound literature search and the aid of an experienced statistician is encouraged. The need of randomization, blinding, and attempting to minimize variation is discussed and recommended. The choosing of good control groups and the employment of pilot studies are useful. Finally, the formulation of new questions to be further responded is expected.Estudos em animais continuam a ser vital para o desenvolvimento da ciência. O objetivo dessa revisão é o de apresentar a novos pesquisadores, uma visão geral dos passos importantes envolvidos no desenho experimental e, ao mesmo tempo, sugerir algumas informações de ordem prática que geralmente estão incluídas no processo da pesquisa. Os pesquisadores devem atentar sempre aos princípios éticos e seguir estritamente o método científico. Hipóteses bem formuladas e objetivas claros são essenciais e práticos. Nesse contexto, uma pesquisa bibliográfica profunda deve ser executada previamente e o pesquisador deve contar, se possível, com o auxilio de um estatístico experiente. A necessidade de randomização, de planejar um estudo cego e de se minimizar a variação são discutidas e enfatizadas. A escolha de bons grupos controles e o emprego de um estudo piloto são recomendados. Finalmente, a formulação de novas questões para serem respondidas por novas pesquisas é esperada.

  10. Experimental and numerical study on mechanical properties of aluminum alloy under uniaxial tensile test

    Directory of Open Access Journals (Sweden)

    O. Daghfas

    2017-01-01

    Full Text Available The main objective is to model the behavior of 7075 aluminum alloy and built an experimental database to identify the model parameters. The first part of the paper presents an experimental database on 7075 aluminum alloy. Thus, uniaxial tensile tests are carried in three loading directions relative to the rolling direction, knowing that the fatigue of aircraft structures is traditionally managed based on the assumption of uniaxial loads. From experimental database, the mechanical properties are extracted, particularly the various fractures owing to pronounced anisotropy relating to material. In second part, plastic anisotropy is then modeled using the identification strategy which depends on yield criteria, hardening law and evolution law. In third part, a comparison with experimental data shows that behavior model can successfully describe the anisotropy of the Lankford coefficient.

  11. A Study of the Protective Effect of Triticum aestivum L. in an Experimental Animal Model of Chronic Fatigue Syndrome.

    Science.gov (United States)

    Borah, Mukundam; Sarma, Phulen; Das, Swarnamoni

    2014-10-01

    Oxidative stress plays a major role in the pathogenesis of chronic fatigue syndrome (CFS). Keeping in view the proven antioxidant activity of Triticum aestivum L., this study has been undertaken to explore the potential therapeutic benefit of this plant in the treatment of CFS. To study the protective effect of the ethanolic extract of the leaves of Triticum aestivum (EETA) in an experimental mice model of CFS. Five groups of albino mice (20-25 g) were selected for the study, with five animals in each group. Group A served as the naïve control and Group B served as the stressed control. Groups C and D received EETA (100 mg/kg and 200 mg/kg b.w.). Group E received imipramine (20 mg/kg b.w.). Except for Group A, mice in each group were forced to swim 6 min each for 7 days to induce a state of chronic fatigue. Duration of immobility was measured on every alternate day. After 7 days, various behavioral tests (mirror chamber and elevated plus maize test for anxiety, open field test for locomotor activity) and biochemical estimations (malondialdehyde [MDA] and catalase activity) in mice brain were performed. Forced swimming in the stressed group resulted in a significant increase in immobility period, decrease in locomotor activity and elevated anxiety level. The brain homogenate showed significantly increased MDA and decreased catalase levels. The extract-treated groups showed significantly (P < 0.05) improved locomotor activity, decreased anxiety level, elevated catalase levels and reduction of MDA. The study confirms the protective effects of EETA in CFS.

  12. Transfer of elements relevant to nuclear fuel cycle from soil to boreal plants and animals in experimental meso- and microcosms

    Energy Technology Data Exchange (ETDEWEB)

    Tuovinen, Tiina S., E-mail: tiina.tuovinen@uef.fi [Department of Environmental Science, University of Eastern Finland, P.O. Box 1627, FI-70211 Kuopio (Finland); Kasurinen, Anne; Häikiö, Elina [Department of Environmental Science, University of Eastern Finland, P.O. Box 1627, FI-70211 Kuopio (Finland); Tervahauta, Arja [Department of Biology, University of Eastern Finland, P.O. Box FI-70211, Kuopio (Finland); Makkonen, Sari; Holopainen, Toini; Juutilainen, Jukka [Department of Environmental Science, University of Eastern Finland, P.O. Box 1627, FI-70211 Kuopio (Finland)

    2016-01-01

    Uranium (U), cobalt (Co), molybdenum (Mo), nickel (Ni), lead (Pb), thorium (Th) and zinc (Zn) occur naturally in soil but their radioactive isotopes can also be released into the environment during the nuclear fuel cycle. The transfer of these elements was studied in three different trophic levels in experimental mesocosms containing downy birch (Betula pubescens), narrow buckler fern (Dryopteris carthusiana) and Scandinavian small-reed (Calamagrostis purpurea ssp. Phragmitoides) as producers, snails (Arianta arbostorum) as herbivores, and earthworms (Lumbricus terrestris) as decomposers. To determine more precisely whether the element uptake of snails is mainly via their food (birch leaves) or both via soil and food, a separate microcosm experiment was also performed. The element uptake of snails did not generally depend on the presence of soil, indicating that the main uptake route was food, except for U, where soil contact was important for uptake when soil U concentration was high. Transfer of elements from soil to plants was not linear, i.e. it was not correctly described by constant concentration ratios (CR) commonly applied in radioecological modeling. Similar nonlinear transfer was found for the invertebrate animals included in this study: elements other than U were taken up more efficiently when element concentration in soil or food was low. - Highlights: • We studied transfer of elements in boreal food chain using meso- and microcosms. • Elements related to nuclear fuel cycle and mining were examined. • Higher uptake at lower soil concentrations was observed for primary producers. • Snails took up elements mainly from food but for U also soil was an element source. • Non-linear transfer of essential elements was observed for herbivore and decomposer.

  13. Stimulation of tendon repair by platelet concentrate, CDMP-2 and mechanical loading in animal models

    OpenAIRE

    Virchenko, Olena

    2007-01-01

    Growth factor delivery may be useful to accelerate the rate of tendon healing. We studied Platelet Concentrate, which in effect can be regarded as a cocktail of growth factors relevant for tendon healing. In a rat Achilles tendon transection model, one postoperative injection of Platelet Concentrate resulted in increased strength even 3 weeks later. Mechanical stimulation improves the repair of ruptured tendons. We studied the effects of platelets upon Achilles tendon regenerates in rats 3, 5...

  14. Multiple mitigation mechanisms: Effects of submerged plants on the toxicity of nine insecticides to aquatic animals.

    Science.gov (United States)

    Brogan, William R; Relyea, Rick A

    2017-01-01

    Understanding the processes that regulate contaminant impacts in nature is an increasingly important challenge. For insecticides in surface waters, the ability of aquatic plants to sorb, or bind, hydrophobic compounds has been identified as a primary mechanism by which toxicity can be mitigated (i.e. the sorption-based model). However, recent research shows that submerged plants can also rapidly mitigate the toxicity of the less hydrophobic insecticide malathion via alkaline hydrolysis (i.e. the hydrolysis-based model) driven by increased water pH resulting from photosynthesis. However, it is still unknown how generalizable these mitigation mechanisms are across the wide variety of insecticides applied today, and whether any general rules can be ascertained about which types of chemicals may be mitigated by each mechanism. We quantified the degree to which the submerged plant Elodea canadensis mitigated acute (48-h) toxicity to Daphnia magna using nine commonly applied insecticides spanning three chemical classes (carbamates: aldicarb, carbaryl, carbofuran; organophosphates: malathion, diazinon, chlorpyrifos; pyrethroids: permethrin, bifenthrin, lambda-cyhalothrin). We found that insecticides possessing either high octanol-water partition coefficients (log K ow ) values (i.e. pyrethroids) or high susceptibility to alkaline hydrolysis (i.e. carbamates and malathion) were all mitigated to some degree by E. canadensis, while the plant had no effect on insecticides possessing intermediate log K ow values and low susceptibility to hydrolysis (i.e. chlorpyrifos and diazinon). Our results provide the first general insights into which types of insecticides are likely to be mitigated by different mechanisms based on known chemical properties. We suggest that current models and mitigation strategies would be improved by the consideration of both mitigation models. Copyright © 2016 Elsevier Ltd. All rights reserved.

  15. Muscular heat and mechanical pain sensitivity after lengthening contractions in humans and animals.

    Science.gov (United States)

    Queme, Fernando; Taguchi, Toru; Mizumura, Kazue; Graven-Nielsen, Thomas

    2013-11-01

    Mechanical sensitivity of muscle nociceptors was previously shown to increase 2 days after lengthening contractions (LC), but heat sensitivity was not different despite nerve growth factor (NGF) being upregulated in the muscle during delayed-onset muscle soreness (DOMS). The discrepancy of these results and lack of other reports drove us to assess heat sensitivity during DOMS in humans and to evaluate the effect of NGF on the heat response of muscle C-fibers. Pressure pain thresholds and pain intensity scores to intramuscular injection of isotonic saline at 48°C and capsaicin were recorded in humans after inducing DOMS. The response of single unmyelinated afferents to mechanical and heat stimulations applied to their receptive field was recorded from muscle-nerve preparations in vitro. In humans, pressure pain thresholds were reduced but heat and capsaicin pain responses were not increased during DOMS. In rats, the mechanical but not the heat sensitivity of muscle C-fibers was increased in the LC group. NGF applied to the receptive field facilitated the heat sensitivity relative to the control. The absence of facilitated heat sensitivity after LC, despite the NGF sensitization, may be explained if the NGF concentration produced after LC is not sufficient to sensitize nociceptor response to heat. This article presents new findings on the basic mechanisms underlying hyperalgesia during DOMS, which is a useful model to study myofascial pain syndrome, and the role of NGF on muscular nociception. This might be useful in the search for new pharmacologic targets and therapeutic approaches. Copyright © 2013 American Pain Society. Published by Elsevier Inc. All rights reserved.

  16. Experimental characterization of the hydro-mechanical behaviour of Meuse/Haute-Marne argilites

    International Nuclear Information System (INIS)

    Escoffier, S.

    2002-04-01

    Within the framework of a feasibility study of underground radioactive waste repository the experimental characterization of the coupled behavior of the host layer is of first importance. This work concerns the experimental characterization in laboratory of the poro-elastic behavior of argillite which constitutes the host layer of the future underground laboratory of ANDRA located at the limit of the Meuse/Haute-Marne. The theoretical approach is the Mechanics of Porous Media defined by Coussy [1991] which has the advantage of providing a formulation of the behavior laws using measurable parameters in laboratory. The difficulties or the feasibility of the characterization tests of these rocks coupled behavior are related to their very low permeability which requires an adaptation of the experimental devices initially used on more permeable rocks. Initially a synthesis on the knowledge of the poro-elastic parameters of Meuse/Haute-Marne argillite is given. Thereafter a first approach of the use of the studies of sensitivity as tools of decision-making aid is proposed. The experimental difficulties encountered by the various experimenters are illustrated by the diversity of the experimental choices, the test duration or by the results disparity. Because of economic, political and ecological stake, the studies of sensitivity could make it possible to direct the experimental efforts by giving indications on the dominating parameters in the coupled behavior of a rock. In the second time after the presentation of the test results of physical characterization 3 types of tests are described: permeability test (pulse test), determination of Biot coefficient under odometric loading and isotropic drained test. The complexity of these tests is related to the attack of the experimental limits. They are presented in detail: theoretical recalls, experimental set up, experimental protocol, unfolding and test results. (author)

  17. A mini-overview of single muscle fibre mechanics: the effects of age, inactivity and exercise in animals and humans.

    Science.gov (United States)

    Jee, Hyunseok; Kim, Jong-Hee

    2017-09-05

    Many basic movements of living organisms are dependent on muscle function. Muscle function allows for the coordination and harmonious integrity of movement that is necessary for various biological processes. Gross and fine motor skills are both regulated at the micro-level (single muscle fibre level), controlled by neuronal regulation, and it is therefore important to understand muscle function at both micro- and macro-levels to understand the overall movement of living organisms. Single muscle mechanics and the cellular environment of muscles fundamentally allow for the harmonious movement of our bodies. Indeed, a clear understanding of the functionality of muscle at the micro-level is indispensable for explaining muscular function at the macro-(whole gross muscle) level. By investigating single muscle fibre mechanics, we can also learn how other factors such Ca2+ kinetics, enzyme activity and contractile proteins can contribute to muscle mechanics at the micro- and macro-levels. Further, we can also describe how aging affects the capacity of skeletal muscle cells, as well as how exercise can prevent aging-based sarcopenia and frailty. The purpose of this review is to introduce and summarise the current knowledge of single muscle fibre mechanics in light of aging and inactivity. We then describe how exercise mitigates negative muscle adaptations that occur under those circumstances. In addition, single muscle fibre mechanics in both animal and human models are discussed.

  18. Transgenic animal model for studying the mechanism of obesity-associated stress urinary incontinence.

    Science.gov (United States)

    Wang, Lin; Lin, Guiting; Lee, Yung-Chin; Reed-Maldonado, Amanda B; Sanford, Melissa T; Wang, Guifang; Li, Huixi; Banie, Lia; Xin, Zhengcheng; Lue, Tom F

    2017-02-01

    To study and compare the function and structure of the urethral sphincter in female Zucker lean (ZL) and Zucker fatty (ZF) rats and to assess the viability of ZF fats as a model for female obesity-associated stress urinary incontinence (SUI). Two study arms were created: a ZL arm including 16-week-old female ZL rats (ZUC-Lepr fa 186; n = 12) and a ZF arm including 16-week-old female ZF rats (ZUC-Lepr fa 185; n = 12). I.p. insulin tolerance testing was carried out before functional study. Metabolic cages, conscious cystometry and leak point pressure (LPP) assessments were conducted. Urethral tissues were harvested for immunofluorescence staining to check intramyocellular lipid (IMCL) and sphincter muscle (smooth muscle and striated muscle) composition. The ZF rats had insulin resistance, a greater voiding frequency and lower LPP compared with ZL rats (P Obesity impairs urethral sphincter function via IMCL deposition and leads to atrophy and distortion of urethral striated muscle. The ZF rats could be a consistent and reliable animal model in which to study obesity-associated SUI. © 2016 The Authors BJU International © 2016 BJU International Published by John Wiley & Sons Ltd.

  19. Experimental results and first {sup 22}Na source image reconstruction by two prototype modules in coincidence of a liquid xenon positron emission tomograph for small animal imaging

    Energy Technology Data Exchange (ETDEWEB)

    Gallin-Martel, M.-L., E-mail: mlgallin@lpsc.in2p3.fr [Laboratoire de Physique Subatomique et de Cosmologie, Universite Joseph Fourier Grenoble 1, CNRS/IN2P3, Institut National Polytechnique de Grenoble, 53 avenue des Martyrs 38026 Grenoble Cedex (France); Grondin, Y. [Laboratoire TIMC/IMAG, CNRS et Universite Joseph Fourier, Pavillon Taillefer 38706 La Tronche Cedex (France); Gac, N. [Laboratoire L2S, UMR 8506 CNRS - SUPELEC - Univ Paris-Sud, Gif sur Yvette F-91192 (France); Carcagno, Y.; Gallin-Martel, L.; Grondin, D.; Marton, M.; Muraz, J.-F; Rossetto, O.; Vezzu, F. [Laboratoire de Physique Subatomique et de Cosmologie, Universite Joseph Fourier Grenoble 1, CNRS/IN2P3, Institut National Polytechnique de Grenoble, 53 avenue des Martyrs 38026 Grenoble Cedex (France)

    2012-08-01

    A detector with a very specific design using liquid Xenon (LXe) in the scintillation mode is studied for Positron Emission Tomography (PET) of small animals. Two prototype modules equipped with Position Sensitive Photo Multiplier Tubes (PSPMTs) operating in the VUV range (178 nm) and at 165 K were built and studied in coincidence. This paper reports on energy, time and spatial resolution capabilities of this experimental test bench. Furthermore, these experimental results were used to perform the first image reconstruction of a {sup 22}Na source placed in the experimental setup.

  20. Experimental results and first 22Na source image reconstruction by two prototype modules in coincidence of a liquid xenon positron emission tomograph for small animal imaging

    International Nuclear Information System (INIS)

    Gallin-Martel, M.-L.; Grondin, Y.; Gac, N.; Carcagno, Y.; Gallin-Martel, L.; Grondin, D.; Marton, M.; Muraz, J.-F; Rossetto, O.; Vezzu, F.

    2012-01-01

    A detector with a very specific design using liquid Xenon (LXe) in the scintillation mode is studied for Positron Emission Tomography (PET) of small animals. Two prototype modules equipped with Position Sensitive Photo Multiplier Tubes (PSPMTs) operating in the VUV range (178 nm) and at 165 K were built and studied in coincidence. This paper reports on energy, time and spatial resolution capabilities of this experimental test bench. Furthermore, these experimental results were used to perform the first image reconstruction of a 22 Na source placed in the experimental setup.

  1. Process, System, Causality, and Quantum Mechanics: A Psychoanalysis of Animal Faith

    Science.gov (United States)

    Etter, Tom; Noyes, H. Pierre

    We shall argue in this paper that a central piece of modern physics does not really belong to physics at all but to elementary probability theory. Given a joint probability distribution J on a set of random variables containing x and y, define a link between x and y to be the condition x=y on J. Define the {\\it state} D of a link x=y as the joint probability distribution matrix on x and y without the link. The two core laws of quantum mechanics are the Born probability rule, and the unitary dynamical law whose best known form is the Schrodinger's equation. Von Neumann formulated these two laws in the language of Hilbert space as prob(P) = trace(PD) and D'T = TD respectively, where P is a projection, D and D' are (von Neumann) density matrices, and T is a unitary transformation. We'll see that if we regard link states as density matrices, the algebraic forms of these two core laws occur as completely general theorems about links. When we extend probability theory by allowing cases to count negatively, we find that the Hilbert space framework of quantum mechanics proper emerges from the assumption that all D's are symmetrical in rows and columns. On the other hand, Markovian systems emerge when we assume that one of every linked variable pair has a uniform probability distribution. By representing quantum and Markovian structure in this way, we see clearly both how they differ, and also how they can coexist in natural harmony with each other, as they must in quantum measurement, which we'll examine in some detail. Looking beyond quantum mechanics, we see how both structures have their special places in a much larger continuum of formal systems that we have yet to look for in nature.

  2. Density profile and cholesterol concentration of serum lipoproteins in experimental animals and human subjects on hypercholesterolaemic diets

    NARCIS (Netherlands)

    Beynen, A.C.; Terpstra, A.H.M.

    1984-01-01

    1. 1. The density profile of Sudan black stained serum lipoproteins was studied in human subjects and various animal species on diets supplemented with cholesterol. 2. 2. In the animals studied (rabbits, calves, mice, chickens, rats and guinea-pigs), the feeding of cholesterol resulted in an

  3. Principles of animal extrapolation

    Energy Technology Data Exchange (ETDEWEB)

    Calabrese, E.J.

    1991-01-01

    Animal Extrapolation presents a comprehensive examination of the scientific issues involved in extrapolating results of animal experiments to human response. This text attempts to present a comprehensive synthesis and analysis of the host of biomedical and toxicological studies of interspecies extrapolation. Calabrese's work presents not only the conceptual basis of interspecies extrapolation, but also illustrates how these principles may be better used in selection of animal experimentation models and in the interpretation of animal experimental results. The book's theme centers around four types of extrapolation: (1) from average animal model to the average human; (2) from small animals to large ones; (3) from high-risk animal to the high risk human; and (4) from high doses of exposure to lower, more realistic, doses. Calabrese attacks the issues of interspecies extrapolation by dealing individually with the factors which contribute to interspecies variability: differences in absorption, intestinal flora, tissue distribution, metabolism, repair mechanisms, and excretion. From this foundation, Calabrese then discusses the heterogeneticity of these same factors in the human population in an attempt to evaluate the representativeness of various animal models in light of interindividual variations. In addition to discussing the question of suitable animal models for specific high-risk groups and specific toxicological endpoints, the author also examines extrapolation questions related to the use of short-term tests to predict long-term human carcinogenicity and birth defects. The book is comprehensive in scope and specific in detail; for those environmental health professions seeking to understand the toxicological models which underlay health risk assessments, Animal Extrapolation is a valuable information source.

  4. Experimental and numerical investigation of a phase-only control mechanism in the linear intensity regime.

    Science.gov (United States)

    Brühl, Elisabeth; Buckup, Tiago; Motzkus, Marcus

    2018-06-07

    Mechanisms and optimal experimental conditions in coherent control still intensely stimulate debates. In this work, a phase-only control mechanism in an open quantum system is investigated experimentally and numerically. Several parameterizations for femtosecond pulse shaping (combination of chirp and multipulses) are exploited in transient absorption of a prototype organic molecule to control population and vibrational coherence in ground and excited states. Experimental results are further numerically simulated and corroborated with a four-level density-matrix model, which reveals a phase-only control mechanism based on the interaction between the tailored phase of the excitation pulse and the induced transient absorption. In spite of performing experiment and numerical simulations in the linear regime of excitation, the control effect amplitude depends non-linearly on the excitation energy and is explained as a pump-dump control mechanism. No evidence of single-photon control is observed with the model. Moreover, our results also show that the control effect on the population and vibrational coherence is highly dependent on the spectral detuning of the excitation spectrum. Contrary to the popular belief in coherent control experiments, spectrally resonant tailored excitation will lead to the control of the excited state only for very specific conditions.

  5. Understanding flocculation mechanism of graphene oxide for organic dyes from water: Experimental and molecular dynamics simulation

    Directory of Open Access Journals (Sweden)

    Jun Liu

    2015-11-01

    Full Text Available Flocculation treatment processes play an important role in water and wastewater pretreatment. Here we investigate experimentally and theoretically the possibility of using graphene oxide (GO as a flocculant to remove methylene blue (MB from water. Experimental results show that GO can remove almost all MB from aqueous solutions at its optimal dosages and molecular dynamics simulations indicate that MB cations quickly congregate around GO in water. Furthermore, PIXEL energy contribution analysis reveals that most of the strong interactions between GO and MB are of a van der Waals (London dispersion character. These results offer new insights for shedding light on the molecular mechanism of interaction between GO and organic pollutants.

  6. Toward an understanding of the neural mechanisms underlying dual-task performance: Contribution of comparative approaches using animal models.

    Science.gov (United States)

    Watanabe, Kei; Funahashi, Shintaro

    2018-01-01

    The study of dual-task performance in human subjects has received considerable interest in cognitive neuroscience because it can provide detailed insights into the neural mechanisms underlying higher-order cognitive control. Despite many decades of research, our understanding of the neurobiological basis of dual-task performance is still limited, and some critical questions are still under debate. Recently, behavioral and neurophysiological studies of dual-task performance in animals have begun to provide intriguing evidence regarding how dual-task information is processed in the brain. In this review, we first summarize key evidence in neuroimaging and neuropsychological studies in humans and discuss possible reasons for discrepancies across studies. We then provide a comprehensive review of the literature on dual-task studies in animals and provide a novel working hypothesis that may reconcile the divergent results in human studies toward a unified view of the mechanisms underlying dual-task processing. Finally, we propose possible directions for future dual-task experiments in the framework of comparative cognitive neuroscience. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.

  7. 5th International Symposium on Experimental Mechanics (5-ISEM) and 9th Symposium on Optics in Industry

    CERN Document Server

    Furlong, Cosme; Barrientos, Bernardino; Pryputniewicz, Ryszard

    2017-01-01

    This book contains papers of the 5th International Symposium on Experimental Mechanics (5-ISEM) and the 9th Symposium on Optics in Industry (9-SOI), whose general theme is Emerging Challenges for Experimental Mechanics in Energy and Environmental Applications. These symposia are organized by Centro de Investigaciones en Optica (CIO) and Mexican Academy for Optics (AMO), under the sponsorship of the Society of Experimental Mechanics (SEM) and other national and international Organizations; Symposia are interdisciplinary forums for engineers, technicians, researchers and managers involved in all fields of Optics, Opto-mechatronics, Mechanics and Mechanical Engineering. · Addresses a broad readership including graduate and postgraduate students, researchers, and engineers working in experimental mechanics and in the application of optical methods · Covers a broad spectrum of topics highlighting the use of optical methods in experimental mechanics, energy, and in the environment.

  8. [Interactions of DNA bases with individual water molecules. Molecular mechanics and quantum mechanics computation results vs. experimental data].

    Science.gov (United States)

    Gonzalez, E; Lino, J; Deriabina, A; Herrera, J N F; Poltev, V I

    2013-01-01

    To elucidate details of the DNA-water interactions we performed the calculations and systemaitic search for minima of interaction energy of the systems consisting of one of DNA bases and one or two water molecules. The results of calculations using two force fields of molecular mechanics (MM) and correlated ab initio method MP2/6-31G(d, p) of quantum mechanics (QM) have been compared with one another and with experimental data. The calculations demonstrated a qualitative agreement between geometry characteristics of the most of local energy minima obtained via different methods. The deepest minima revealed by MM and QM methods correspond to water molecule position between two neighbor hydrophilic centers of the base and to the formation by water molecule of hydrogen bonds with them. Nevertheless, the relative depth of some minima and peculiarities of mutual water-base positions in' these minima depend on the method used. The analysis revealed insignificance of some differences in the results of calculations performed via different methods and the importance of other ones for the description of DNA hydration. The calculations via MM methods enable us to reproduce quantitatively all the experimental data on the enthalpies of complex formation of single water molecule with the set of mono-, di-, and trimethylated bases, as well as on water molecule locations near base hydrophilic atoms in the crystals of DNA duplex fragments, while some of these data cannot be rationalized by QM calculations.

  9. Accelerating recovery from jet lag: prediction from a multi-oscillator model and its experimental confirmation in model animals

    Science.gov (United States)

    Kori, Hiroshi; Yamaguchi, Yoshiaki; Okamura, Hitoshi

    2017-04-01

    The endogenous circadian clock drives oscillations that are completely synchronized with the environmental day-night rhythms with a period of approximately 24 hours. Temporal misalignment between one’s internal circadian clock and the external solar time often occurs in shift workers and long-distance travelers; such misalignments are accompanied by sleep disturbances and gastrointestinal distress. Repeated exposure to jet lag and rotating shift work increases the risk of lifestyle-related diseases, such as cardiovascular complaints and metabolic insufficiencies. However, the mechanism behind the disruption of one’s internal clock is not well understood. In this paper, we therefore present a new theoretical concept called “jet lag separatrix” to understand circadian clock disruption and slow recovery from jet lag based on the mathematical model describing the hierarchical structure of the circadian clock. To demonstrate the utility of our theoretical study, we applied it to predict that re-entrainment via a two-step jet lag in which a four-hour shift of the light-dark cycle is given in the span of two successive days requires fewer days than when given as a single eight-hour shift. We experimentally verified the feasibility of our theory in C57BL/6 strain mice, with results indicating that this pre-exposure of jet lag is indeed beneficial.

  10. Alexander von Humboldt: galvanism, animal electricity, and self-experimentation part 1: formative years, naturphilosophie, and galvanism.

    Science.gov (United States)

    Finger, Stanley; Piccolino, Marco; Stahnisch, Frank W

    2013-01-01

    During the 1790s, Alexander von Humboldt (1769-1859), who showed an early interest in many facets of natural philosophy and natural history, delved into the controversial subject of galvanism and animal electricity, hoping to shed light on the basic nature of the nerve force. He was motivated by his broad worldview, the experiments of Luigi Galvani, who favored animal electricity in more than a few specialized fishes, and the thinking of Alessandro Volta, who accepted specialized fish electricity but was not willing to generalize to other animals, thinking Galvani's frog experiments flawed by his use of metals. Differing from many German Naturphilosophen, who shunned "violent" experiments, the newest instruments, and detailed measurement, Humboldt conducted thousands of galvanic experiments on animals and animal parts, as well as many on his own body, some of which caused him great pain. He interpreted his results as supporting some but not all of the claims made by both Galvani and Volta. Notably, because of certain negative findings and phenomenological differences, he remained skeptical about the intrinsic animal force being qualitatively identical to true electricity. Hence, he referred to a "galvanic force," not animal electricity, in his letters and publications, a theoretical position he would abandon with Volta's help early in the new century.

  11. Progress in animal experimentation ethics: a case study from a Brazilian medical school and from the international medical literature.

    Science.gov (United States)

    Ramalli, Edvaldo Luiz; Ho, Wanli; Alves, Mônica; Rocha, Eduardo Melani

    2012-09-01

    This study describes in Brazil and in the global biomedical community the time course of the development of animal research welfare guidelines. The database of the Ethics Committee of the Faculty of Medicine of Ribeirao Preto (EC/FMRP-USP), Brazil, was surveyed since its inception in 2002 as the regulations became more stringent to provide better protection of animal research welfare at this institution. Medline database was evaluated to identify the number of publications in the period between 1968 and 2008 that used research animals and were in compliance with established ethics guidelines. The EC/FMRP-USP evaluated 979 projects up until 2009. Most of the applications came from Department of Physiology and the most frequently requested species was the rat. In 2004, national research funding agencies started to request prior approval from institutional review ethics committees prior to application review and this requirement became federal law in Brazil in 2008. The analysis of international publications revealed a relative reduction in studies involving research animals (18% in 1968 to 7.5% in 2008). The present work showed that in the last four decades major changes occurred in the guidelines dictating use of research animals occurred and they are being adopted by developing countries. Moreover, animal welfare concern in the scientific community preceded the introduction of journal guidelines for this purpose. Furthermore, in Brazil it was anticipated that laws were needed to protect animal research welfare from being not upheld.

  12. Shock wave effects in copper: Design of an experimental device for post recovery mechanical testing

    International Nuclear Information System (INIS)

    Buy, Francois; Llorca, Fabrice

    2002-01-01

    The mechanical behavior of metals may prove high changes with strain rate and pressure loading history. In order to investigate the effect of a shock on the ulterior mechanical behavior of high purity copper, we set up an experimental device inspired from G. T. Gray III'