Mice experiment

The two blind mice experiment of Alyan and Jander (1994) used the pup-retrieving behavior of female house mice to determine the visual cues they use for orientation in an arena of Im diameter. A strain of blind mice did not orient as well as intact mice. In different experiments, neither sighted nor blind mice appeared to use olfactory cues such as scent trails in sand, or the odors of wooden blocks in the arena, to find their nest after their arena had been rotated by 90 degrees. Such rotation misled them on their way home, despite landmarks in their arena with odor that should have been familiar to them. We know little on the role of olfactory cues in such short-range orientation. 

The crucial role of this export system in protecting the brain can be illustrated by the use of specially bred mice in which the gene for p-glycoprotein is knocked out. When normal and knockout mice are exposed to the antihelminthic drug ivermectin, the null mice experience neurotoxic effects at doses 100 times less than the normal animals and also have levels of the drug in the brain almost 100 times those in the normal (wild type) mice. 

In vivo studies using mouse models have proved that curcumin modifies apoptosis resistance, leading to the inhibition of tumor formation and the prevention of adenoma development in the intestinal tract. The chemopreven-tive effect of curcumin for intestinal tumors in Min/+ mice was investigated. A dietary level of 0.15% curcumin decreased tumor formation in Min—/— mice by 63%. Examination of intestinal tissue from the treated animals showed the tumor prevention by curcumin was associated with increased enterocyte apoptosis and proliferation. Curcumin also decreased expression of the oncoprotein (S-catenin in the erythrocytes of the Min/+ mouse, an observation previously associated with an antitumor effect. Curcumin enhanced PhlP-induced apoptosis and inhibited PhIP-induced tumorigenesis in the proximal small intestine of Ape (min) mice. Experiments performed on intestinal tumors in C57BL/6J-Min/+ (Min/+) mice demonstrated that curcumin has a regulatory role in lymphocyte-mediated immune function [Churchill et al., 2000]. Furthermore, levels of COX-2 protein expression have been found to reflect the retardation of adenoma development in mouse intestines after treatment with curcumin [Tunstall et al., 2006]. 

Figure 5. In vivo activity of three newer sulfapyrimidines against nine infections in mice Experiments of E. Grunberg...

It is a specific nonanticoagulant rodenticide, acceptable to rodents without prebaiting. Its acute oral toxicity is IS mg/kg for rats, and 20 mg/kg for mice. Experiments are still carried out (Dreikom et al., 1979). 

The enhancement of the SM share in PL under the simultaneous in-erease the relative content of lysoforms is usually eonsidered as the adaptation reaction of the membrane system on the different actions [17]. In this coimection it is interestingly to note following result. The common direct correlation between the LPC content and SM share in PL is revealed for lipids of the liver and brain mice (experiment 2) and the native lecithin,... 

Figure 12 CGD mice lack the gp91 phox subunit of NADPH oxidase, (a) Immunohis-tochemistry (above) and immunoblotting (below, note the lower molecular weight is common in mice) experiments show that CGD mice lack the gp91 phox subunit of the en2yme, compared to wild mice (darker stain). Expression of p22 phox is similar in the CGD versus the wild mice. Note that in the CGD mice, the subunit is absent from the PA and alveolar (A) epithelial cells as well as from phagocytes (arrows). (From Ref. 99.)...

In mice experiments intraperitoneal administration of partially purified P-sitosterol fractions of the fruit extract showed significant estrogenic activity an anti-estrogenic effect has also been demonstrated. ... 

Water extracts of Y. glauca Nutt, in mice experiments have shown antitumor activity against B16 melanoma (foster and duke). 

Table VI. Protocol of long-term mouse experiment...

Design of the mouse experiments has been described elsewhere in detail. In short, a sex-mismatched (male into female) diallelic (CD45.2/Ly5.2 into CD45.1/Ly5.1) C56B1/6J mouse model was used. After 48 and 72 hours... 

In mouse experiments in vivo, dimethylformamide did not induce sister chromatid... 

Ideally, if mouse experiments are to be vised to estimate the rate of induction of gene or chromosomal mutations, chemicals should be tested at enough doses to establish a dose-response curve. However, if the purpose is simply to confirm that a chemical is mutagenic in a mammal, then a single positive result at a single dose is sufficient. A large dose (close to the maximum that is tolerated by the animal) can be given, and the concentration-time relations can be adjusted so that other toxicity does not unduly influence the mutant yield. 

Molnar, Beladii, and Foldes [69] studied antimycobacterial activity of five phenothiazine derivatives including chlorpromazine, levomeprazine, promazine, promethazine, and diethazine. The growth of Mycobacterium tuberculosis, Mycobacterium bovis, and Mycobacterium butyricum was found to be inhibited by chlorpromazine at practically identical concentrations. The minimum inhibitory concentrations for Mycobacterium tuberculosis were chlorpromazine and levomeprazine 10 xg/ml diethazine and promethazine 20 xg/ml whilst chlorpromazine sulphoxide was ineffective even at 100 xg/ml. Chlorpromazine and promethazine exerted a measurable bactericidal activity on Mycobacterium tuberculosis at 50 xg/ml total destruction of the organism and loss of acid fastness in part of the cells were shown at 300 xg/ml. Preliminary studies in mouse experiments revealed that phenothiazine derivatives were ineffective. 

For example, the range of concentrations in 36 digests of fetal tissues sacrificed 1 hour after injection in the mouse experiment ranged from 116 to 30,342 fig (Haque and Vrazel 1998). This variability may due to an inconsistent mass breakthrough of fibers associated with the bolus intravenous administration (Cunningham and Pontefract 1974). It is expected that the extent of transplacental transfer of fibers would be much less with inhalation, oral, or dermal exposures. 

FcRn, can also be influenced by mutations [128, 129]. These mutations must, however, be designed to differentially affect the binding to the receptor in a pH dependent manner, such that recychng of the IgG works properly. Encouraging mouse experiments have been reported (summarized in Presta [125]), but chnical trials in patients have not yet been carried out. 

How is this cell-type specificity achieved As described in Section 4 in this chapter, transfection and transgenic mouse experiments have shown that both the enhancers and the promoters of immunoglobulin genes confer cell-type specificity. The molecular mechanism by which these elements confer cell-type specificity remains to be identified. Nevertheless, it seems likely that it is the cell-type specificity of these transcription elements that accounts for the inability of non-lymph-oid cells to express transfected immunoglobulin genes. However, it is notable that, whereas using both cellular transfection and transgenic mouse assays, the IgH en-... 

Taking various factors into consideration, it is probably impractical and not realistic to make risk estimations from the carcinogenicity data on rodents given a single carcinogen. However, for a simple extrapolation of animal data for risk estimation, TDjq values, which are the doses needed to develop cancers in 50% of animals fed on carcinogens [IQ, Trp-P-1, Trp-P-2, Glu-P-1, Glu-P-2, AaC, and MeAaC] for their fife time, have been calculated based on mouse experiments... 

Thomson s first graduate student, Ernest Rutherford, continued to investigate the nature of the atom. In the early twentieth century, Rutherford carried out a now-fa-mous experiment in which radioactive particles were shot through extremely thin gold foil. While some bounced off of the nuclei in different directions, most of the particles... 

High polarization of nuclear spins through dynamic nuclear polarization in liquid state has enabled the direct monitoring of metabolites in vivo. The design and testing of the compressed sensing suited for a flyback 3D-MRSI sequence are presented. Phantom tests validated the accuracy of the compressed sensing approach and initial mouse experiments demonstrated in vivo feasibility. 

The Pearson-Mawby softness parameter played a central role in this work. Since the use of this parameter does not permit the comparison of ions with different oxidation numbers (Ahrland 1968), the analyses in Turner et al. (1983) and Williams et al. (1982) were confined largely to the application of equation 2 to groups of ions of a given charge. For the 14 divalent ions used in the mouse experiment (Williams et al. 1982), a correlation represented by r = 0.36 was found with standard error s = 0.57. One aim of the present study is to demonstrate a predictive ability for toxicity which can be used for ions of any oxidation number and which is hence independent of ap. 

Participants. Ten participants were recruited from the university, high school and members of the public in the Manchester Area (mean age=18.8, SD=9.1). All participants (8 female, 2 male) have some computer and mouse experience (mean=3.2 years, SD=2.6). None of the participants was familiar with the target acquisition task. All participants signed informed consent forms before the experiment. 

Ca-DTPA (the calcium trisodium salt of diethylene triamine penta-acetic acid) has been used to remove various actinide elements from accidentally contaminated adults. Mays et al. (1) have pointed out that the dose predicted to kill the human foetus (as estimated from rat and mouse experiments) is within or under the range of the previously recommended daily dose of 26—36 /nmole Ca-DTPA. The toxicity of Ca-DTPA is largely due to the depletion of zinc and perhaps manganese, which causes inhibition of DNA synthesis. The authors suggest the use of the zinc salt of DTPA rather than Ca-DTPA. 

Exposure studies have been made using mice and rats (257). These experiments have demonstrated species differences in butadiene toxicity and carcinogenicity. Butadiene was found to be a potent carcinogen in the mouse, but only a weak carcinogen in the rat. The interpretations have focused on differences in toxification rates and detoxification metaboHsms as causative factors (257). The metaboHsm is beHeved to proceed through intermediates involving butadiene monoepoxide and butadiene diepoxide (257). A similar mechanism has been proposed for its biodegradation pathway (258). 

Reproductive Toxicity. No data are available that impHcate either hexavalent or trivalent chromium compounds as reproductive toxins, unless exposure is by way of injection. The observed teratogenic effects of sodium dichromate(VI), chromic acid, and chromium (HI) chloride, adininistered by injection, as measured by dose-response relationships are close to the amount that would be lethal to the embryo, a common trait of many compounds (111). Reported teratogenic studies on hamsters (117,118), the mouse (119—121), and rabbits (122) have shown increased incidence of cleft palate, no effect, and testicular degeneration, respectively. Although the exposures for these experiments were provided by injections, in the final study (122) oral, inhalation, and dermal routes were also tried, and no testicular degeneration was found by these paths. 

If DNA from two different species are mixed, denatured, and allowed to cool slowly so that reannealing can occur, artificial hybrid duplexes may form, provided the DNA from one species is similar in nucleotide sequence to the DNA of the other. The degree of hybridization is a measure of the sequence similarity or relatedness between the two species. Depending on the conditions of the experiment, about 25% of the DNA from a human forms hybrids with mouse DNA, implying that some of the nucleotide sequences (genes) in humans are very similar to those in mice. Mixed RNA DNA hybrids can be created in vitro if single-stranded DNA is allowed to anneal with RNA copies of itself, such as those formed when genes are transcribed into mRNA molecules. 

Desmoplakin is the most abundant desmosomal component that plays a critical role in linking intermediate filament networks to the desmosomal plaque. Desmoplakin forms rod-like dimers that bind to intermediate filaments and to the cadherin-associated proteins plakoglobin and plakophilin. Gene knock-out experiments have revealed an essential role of desmoplakin in establishing cell-cell contacts in early mouse embryos. 

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