Novel Object Test

Specifically, these studies found that 5-HT1A-R null animals showed increased anxiety-like behavior in the open field, elevated plus maze, elevated zero maze, and novel object tests. 5-HT1A-R KOs were also less immobile in the forced swim and tail suspension tests, the same response induced in these tests by antidepressant drugs. However, it is unclear whether this decreased immobility truly reflects an antidepressant-like coping reaction mediated by increased 5-HT transmission or whether it simply reflects an increased stress response in these anxiety-prone mutant mice (12). 

A PDE10A inhibitor may also have the potential to treat the cognitive symptoms of schizophrenia. The principal evidence for this claim is papaverine reversal of a PCP-induced deficit in the EDID-set shifting assay in rats [35]. This assay translates into human behavior in the form of the Wisconsin Card Sorting Test (WCST). EDID-set shifting is a test of executive function, a measure in which schizophrenics have a robust deficit. It has also been shown recently that papaverine is efficacious in the Novel Object Recognition cognition assay [36]. 

Any video-tracking system (see Table 18.2 for details) may be useful for measuring amount of movement and position within the test apparatus. Conversely, the apparatus may be sectioned off, and duration in each section can be recorded, comparing the perimeter sections to the novel object section (24) (see Note 34). 

This test exploits a natural tendency of rodents to explore novel objects and to show an exploratory preference for replaced or displaced objects. The dependence of object recognition memory on the hippocampus is related to the protocol of a test. Short delays between initial exploration phase and a memory test make ORtest independent from the hippocampus (136), however, when longer delays (hours) are implemented, OR memory depends on hippocampus function (158, 159). Object memory impairment is demonstrated when an animal shows no preference in exploration (close proximity, nose contact) of a new or displaced object. 

Mice lacking 5-HT3A receptors (5-HT3A-7-) might demonstrate an anxiolytic phenotype. These mice spent more time in the open arms of the elevated plus maze (32,33), were more active with a novel object (33) and, under certain conditions, spent more time in the illuminated area in the light/dark test (33)... 

Novel object discrimination testing was used to measure B(a)P-induced behavioral effects as described in our recent report (Sheng et al., 2010). Data in Figure 20.7 show that control offspring mice were better... 

Our ultimate objective is to produce automatically with laboratory-scale reactors polymers with pre-defined molecular characteristics in reasonable amounts for test purposes. Whatever control is exercised over the chemistry of a polymerization to introduce novel structural features into polymer chains, the final molecular weight distribution (MWD) of the product is always of importance hence attention has been given to... 

More debatable is the use of placebo in conditions when effective treatments already exist. In these situations, ethical objections can be made to assigning patients to an inferior treatment. Moreover, families may refuse enrollment into such studies, thus decreasing the representativeness of the study sample. When testing an experimental medication in situations where effective treatment already exists, different types of questions can arise. We may be interested in testing whether the novel treatment is (2) better than no treatment (or non-specific treatment), (2) comparable to an established treatment of proven efficacy, or (3) superior to... 

It may seem perverse to end such a comprehensive and critical account of the preclinical testing of biopharmaceuticals with ideas that are directed as much at the what and how to investigate as at the ultimate evaluation of experimental results. But, as the depth of the opening quotation subtly suggests, it is essential to consider and reconsider the objectives of toxicity experiments before it is possible to decide the value of their results in permitting safe and effective development of these novel and sometimes surprising products. 

Therefore, an important objective in the theory branch of M/C interface research is to envisage new types of interatomic potentials suitable for modeling M/C interfaces to bridge the length scale gap between theory and experiments. In this context, ab initio studies are very useful firstly, for exploring the qualitative nature of M/C chemistry which must be captured by novel model interaction potentials secondly, to provide a broad database for testing new interaction potentials. 

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