Experiments, animal, evaluating

To determine the nociceptive threshold of the mice, the hot plate test and the tail flick test were used. Drugs used are dissoved in sterile distilled water from icv administration immediately prior to injection at 5 pl/kg or 5pi mouse, respectively. The icv injection was performed and the site of administration of the peptide was verified in all animals by the injection of 1% methylene blue and the examination of the dye distribution in the cerebral ventricles at the termination of the experiment. To evaluate the hot plate and tail flick test responses detailed below, a control latency (To) was obtained from the mean of two latencies determined prior to drug injection test latencies (T1) were determined at various times after injection for each animal. The percentage of analgesia was calculated as (Ti -To)/ (T2 -To) x 100 where the cut off times (T2) for the hot plate and tail flick test were 60 and 15s, respectively. The median antinociceptive dose (ED50) and 95% confidence limits were calculated according to the method of Litchfield and Wilcox. 

Biomedical Research. Veterinarians in charge of laboratory animals are responsible for the health and well-being of the animals used in the laboratory. They may oversee as many as 70,000 such animals, many of which are genetically engineered mice. They supervise teams of veterinary technicians and other trained personnel who take care of these animals on a daily basis. They also assess proposed experiments and evaluate how well they conform to regulations regarding laboratory animals. 

The degree of confidence in the final estimation of risk depends on variability, uncertainty, and assumptions identified in all previous steps. The nature of the information available for risk characterization and the associated uncertainties can vary widely, and no single approach is suitable for all hazard and exposure scenarios. In cases in which risk characterization is concluded before human exposure occurs, for example, with food additives that require prior approval, both hazard identification and hazard characterization are largely dependent on animal experiments. And exposure is a theoretical estimate based on predicted uses or residue levels. In contrast, in cases of prior human exposure, hazard identification and hazard characterization may be based on studies in humans and exposure assessment can be based on real-life, actual intake measurements. The influence of estimates and assumptions can be evaluated by using sensitivity and uncertainty analyses. - Risk assessment procedures differ in a range of possible options from relatively unso-... 

The term alternative includes all procedures which can completely replace the need for animal experiments, reduce the number of animals required, or diminish the amount of distress or pain suffered by animals in meeting the essential needs of man and other animals. Its purpose is to promote the development and implementation of new methods to Replace, Reduce, Refine (the 3 Rs ) animal testing with modem alternative approaches. Russell and Burch [4] proposed the framework of the 3 Rs more than 40 year ago. The authors proposed that all research using animals should be evaluated to see if the 3 Rs could be applied. Since that landmark publication, significant progress has been made, especially in the arena of regulatory testing [5]. 

It is imperative, however, to understand the probabilistic nature of such experiments a promising profile on pharmacogenomic and toxicogenomic screens will enhance the likelihood of having selected an ultimately successful compound, and will achieve this goal quicker than conventional animal experimentation, but will do so only with a certain likelihood of success. The less reductionist approach of the animal experiment will still be needed. It is to be anticipated, however, that such approaches will constitute an important, time- and resource-saving first evaluation or screening step that will help to focus and reduce the number of animal experiments that will ultimately need to be conducted. 

Phytochemicals have been the subject of many studies evaluating their effects in relation to common chronic human illnesses such as cancer and cardiovascular diseases. These studies encounter difficulties in using this information to influence the dietary patterns of consumers because in the past they have used models or experiments with animals. However, in the last decade, researchers have moved away from animal studies in favour of human cell models or human intervention studies. Scientists still need to determine the likely incidence of illness from exposure to known amounts of a given natural compound in the diet and specifically in relation to the complex matrices of whole foods. Therefore, it is inevitable that some animal studies have to be continued for toxicological studies. 

Thus, the tetravalency, anti-inflammatory properties and molecular stability of slgA make it particularly suitable for protective passive immunity when applied to mucosal surfaces. To date, the clinical evaluation of slgA protection in humans and animal models has been very limited. Indeed most studies have employed monomeric IgA monoclonal antibodies [3,15]. Hence, differences in IgA and IgG protective activities at the mucosal level have often not been observed [15]. Only a few studies have demonstrated the superior activity of polymeric IgA or slgA compared with monomeric IgG or IgA [16]. In order to determine the efficacy of slgA, future animal experiments and clinical trials are needed to compare the activities of IgG monoclonal antibodies and their slgA counterparts. The ability to engineer slgAs in plants will allow these comparisons to be made [17]. 

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