Satellite animals

Blood Collection. In rodent studies, large numbers of satellite animals (often close to the number used in the main study phase) are usually needed for pharmacokinetic blood sampling, whereas with most nonrodent species, blood samples can be collected from the main study animals without compromising their health status. 

Includes satellite animals for pharmacokinetic evaluation. bNumber of animals/group includes several animals. 

Repeated blood sampling is easier in the rabbit than in the rat due to its greater blood volume. Satellite animals are not usually required. 

Other assays for geno-toxicity can be performed, e.g. the in vivo/in vitro unscheduled DNA-synthesis in isolated hepatocytes. As this assay is not compatible with routine histopathology, satellite animals have to be used for the fresh isolation of hepatocytes. 

Even with satellite animals, repeated sampling within a rodent species is often not performed. Usually, each animal contributes to the data at a single time point. When the animal is sacrificed to obtain the pharmacokinetic data, these animals are said to be destructively sampled. The number of animals in such studies is large and costly since often a study has many different dose levels, are dosed in both males and females, and samples are collected at many time points. As a com-... 

Interval or satellite groups have been discussed at two earlier points in this chapter. They allow measurement of termination parameters at intervals other than at termination of the study. They are also useftd when the manipulation involved in making a measurement (such as the collection of an extensive blood sample), while not terminal, may compromise (relative to other animals) the subject animals. Another common use of such groups is to evaluate recovery from some observed effect at study termination. 

These data may be obtained from all animals on a toxicity study, or from representative subgroups, from satellite groups, or from separate studies. 

Toxicokinetic measurements performed in the toxicity study, either in all animals or in representative subgroups or in satellite groups. 

Microwaves broadcast from the SPS would be received with about 85% efficiency. A conventional microwave antenna is even better, but the cost and complexity are much greater. Rectennas would be several kilometers across and crops and farm animals could be raised under the rectenna, since the thin wires used only slightly reduce sunlight. For best efficiency the satellite antenna would be between 1 and 1.5 kilometers in diameter and the ground rectenna around 14 kilometers by 10 kilometers. This would allow the transfer of 5 to 10 gigawatts of power. 

And although om natural and personal detector, the retina, shows us a tranquil sky, with a light scatter of stars across it, striking only by its steadfast inaction, the new sky revealed by telescopes and satellites sensitive to invisible emissions is one of tempest. It is animated by the birth of clouds, the creative explosion of stars and the transition of the Universe from opacity to transparence. Human perception now contemplates regions once forbidden to it. 

Silverberg and See also point out that often proper planning will allow assessment of an excipient s toxicity in a relatively efficient manner. A less expensive study within a study can be conducted by developing new excipients concurrently with the development of new drugs. Satellite groups of animals receiving an excipient... 

It has been estimated that 1.3 x 1016 Bq of 239+240 pu has been released to the environment from atmospheric detonation of nuclear weapons that 7.9 x 1014 Bq of 238Pu has been released, mosdy from bum-up of the nuclear powered satellite SNAP-9a and that 3.7 x 1013 Bq of 239+240 Pu was released by the Chernobyl accident (167,168). Many studies have been done to determine the cumulative fallout on soils, plants, bodies of water, animals, and humans. For example, the cumulative 239+240 pu fallout in forest and grasslands and in the liver of eldedy humans in Bavaria, Germany are approximately 50 Bq/m2 and 0.02 Bq/kg wet mass, respectively (167). 

One category of intramolecular RNA catalysis produces a 2, 3 -cyclic phosphate and 5 -OH terminus on the reaction products. A number of small plant pathogenic RNAs (viroids, satellite RNAs, and virusoids), a transcript from a Neurospora mitochondrial DNA plasmid, and the animal vims hepatitis delta vims (HDV) undergo a self-cleavage reaction in vitro in the absence of protein. The reactions require neutral pH and Mg2... 

Animals that comprise the satellite group for follow-up studies should be kept under observation for 14 days without treatment. This procedure detects persistence of toxic effects (if any), as well as manner of recovery. A careful clinical examination should be made every day. Action should be taken to minimize the loss of experimental animals, (e.g., identifying animals that are moribund, doing necropsy, refrigeration of animals that are found dead, sacrificing weak or moribund animals). 

In the subchronic toxicity study, if interim sacrifices are planned, the number of animals should be increased so that there is no shortage of animals at the termination of the study this ensures meaningful conclusions about the test chemical s toxicity. In addition, a satellite group of 20 animals (10 of each gender) may be treated with the high dose of the test chemical for 90 days. These animals should be observed for signs of adverse effects, (e.g., reversibility, persistence, delayed occurrence of toxic effects). The observation period should last for a posttreatment period of appropriate length not less than 28 days. 

The observation period for the subchronic oral toxicity should be at least 90 days. Animals in a satellite group scheduled for follow-up observations should be kept for a further period of 28 days without treatment to detect recovery from, or persistence of, toxic effects. Careful clinical examination should be made at least once each day. Additional observations should be made and appropriate actions taken to minimize loss of animals these actions include necropsy or refrigeration of those found dead, or isolation, or sacrifice of weak or moribund animals. The animals are dosed with the test chemical ideally 7 days per week for 90 days. However, based primarily on practical considerations, dosing by gavage or capsules 5 days per week is acceptable. 

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