Recovery animals

Week 8—full necropsy in recovery animals See Appendix C Yes from sternum See Appendix D... 

The rationale for the need of recovery animals was frequently discussed. For drag substances which require chronic (live time) treatment (e.g. oral anti-diabetics, drags for treatment of hypertension, anti-Parkinson drugs, etc.) the question of recovery is less important than in the case of anti-infectives with, in most cases, short treatment periods where mild symptoms of intolerance, e.g. diarrhoea, are observed. However, inclusion of recovery animals is recommended in general because at the stage of development where first clinical studies are conducted, the whole set of indications is not finally known and line extensions can happen. One example is the use of quinolones and other anti-infectives for the treatment of cystic fibrosis. Another example is drugs used for chemotherapy of malignant diseases where recovery has to be studies anyway. 

Deodorant A cAMP phosphodiesterase has been discovered that is found predominantly in olfactory sensory neurons (Yan et al., 1995, Proc. Natl. Acad. Sci. 10 9677). The enzyme is activated by Ca2+. What do you think this enzyme does, and why do you think it is regulated by calcium (Hint Study the response and recovery animations in the Conceptual Insights module on signaling pathways.)... 

Forebrain cholinergic neurons in male rats were le-sioned with ibotenic acid using stereotaxic injections. Following 4-7 days of recovery, animals were tested in a water maze task to find the hidden platform as a measure of spatial working memory. Four trials were conducted... 

Based on tests with laboratory animals, aniline may cause cancer. The National Cancer Institute (NCI) and the Chemical Industry Institute of Toxicology (CUT) conducted lifetime rodent feeding studies, and both studies found tumors of the spleen at high dosage (100 —300 mg/kg pet day of aniline chloride). CUT found no tumors at the 10—30 mg/kg per day feeding rates. The latter value is equivalent to a human 8-h inhalation level of 17—50 ppm aniline vapor. In a short term (10-d) inhalation toxicity test by Du Pont, a no-effect level of 17 ppm aniline vapor was found for rats. At high levels (47—87 ppm), there were blood-related effects which were largely reversible within a 13-d recovery period (70). 

Sevoflurane. Sevoflurane, l,l,l,3,3,3-hexafluoro-2-propyl fluromethyl ether [28523-86-6] is nonpungent, suggesting use in induction of anesthesia. The blood/gas partition coefficient is less than other marketed products (Table 1) yet similar to nitrous oxide, suggesting fast onset and recovery. In animal studies, recovery was faster for sevoflurane than for isoflurane, enflurane, or halothane (76). Sevoflurane is stable to light, oxygen, and metals (28). However, the agent does degrade in soda lime (77). 

Similar results have been reported in sublethaHy and lethaHy irradiated dogs, where G-CSF reduced the severity and duration of neutropenia and the duration of thrombocytopenia (161). G-CSF increases the survival of lethaHy irradiated animals by inducing eadier recovery of neutrophils and platelets. GM-CSF also decreases the severity and duration of neutropenia in dogs exposed to 2.4 Gy (2400 rad) TBI, but does not influence monocyte or lymphocyte recovery (162), indicating its expected selective action. 

Fig. 6. Approaches to minimising entrapment and impingement of fish and large aquatic invertebrates, eg, blue crabs, on trash screens at intakes, (a) An inlet pump house with vertical traveling screens mounted flush with a river shoreline to minimise obstmctions to animal movements (b) parallel flow to direct fish to a recovery chamber that returns to the water body (c) a velocity cap atop a vertical, offshore inlet induces a horizontal flow which fish avoid...

Fecal Goliforms. Eecal coliforms are those originating from the intestines of warm-blooded animals. Eecal coliforms can be deterrnined by a multiple-tube procedure, which must be appHed to a positive presumptive test for optimum recovery of fecal coliforms (20). Incubation must be at 44.5 0.2°C for 24 2 h. Gas production during incubation is positive evidence of fecal coliform poUution. 

Carbon dioxide gas is used to immobilize animals prior to slaughtering them (46). In addition to providing a humane slaughtering technique, this results in better quaHty meat. The CO2 increases the animal s blood pressure, thereby increasing blood recovery. The increased accuracy obtainable in the killing operation reduces meat losses because of cut shoulders. 

By-Products. The biomass from the fungal fermentation process is called mycellium and can be used as a supplement for animal feed since it contains digestable nutrients (25,26). The lime-sulfuric purification and recovery process results in large quantities of calcium sulfate cake, which is usually disposed of into a landfill but can find limited use in making plaster, cement, waUboard, or as an agricultural soil conditioner. The Hquid extraction purification and recovery process has the advantage of Htde soHd by-products. 

Recovery. The principal purpose of recovery is to remove nonproteinaceous material from the enzyme preparation. Enzyme yields vary, sometimes exceeding 75%. Most industrial enzymes are secreted by a microorganism, and the first recovery step is often the removal of whole cells and other particulate matter (19) by centrifugation (20) or filtration (21). In the case of ceU-bound enzymes, the harvested cells can be used as is or dismpted by physical (eg, bead mills, high pressure homogenizer) and/or chemical (eg, solvent, detergent, lysozyme [9001 -63-2] or other lytic enzyme) techniques (22). Enzymes can be extracted from dismpted microbial cells, and ground animal (trypsin) or plant (papain) material by dilute salt solutions or aqueous two-phase systems (23). 

The ability to identify and quantify cyanobacterial toxins in animal and human clinical material following (suspected) intoxications or illnesses associated with contact with toxic cyanobacteria is an increasing requirement. The recoveries of anatoxin-a from animal stomach material and of microcystins from sheep rumen contents are relatively straightforward. However, the recovery of microcystin from liver and tissue samples cannot be expected to be complete without the application of proteolytic digestion and extraction procedures. This is likely because microcystins bind covalently to a cysteine residue in protein phosphatase. Unless an effective procedure is applied for the extraction of covalently bound microcystins (and nodiilarins), then a negative result in analysis cannot be taken to indicate the absence of toxins in clinical specimens. Furthermore, any positive result may be an underestimate of the true amount of microcystin in the material and would only represent free toxin, not bound to the protein phosphatases. Optimized procedures for the extraction of bound microcystins and nodiilarins from organ and tissue samples are needed. 

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