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Connor, R. J., Kawaoka, Y., Webster, R. G., & Paulson, J. C. (1994). Receptor specificity in human, avian, and equine H2 and H3 influenza virus isolates. Virology, 205(1), 17–23.
Abstract: The receptor specificity of 56 H2 and H3 influenza virus isolates from various animal species has been determined to test the relevance of receptor specificity to the ecology of influenza virus. The results show that the receptor specificity of both H2 and H3 isolates evaluated for sialic acid linkage specificity and inhibition of hemagglutination by horse serum correlates with the species of origin, as postulated earlier for H3 strains based on a limited survey of five human, three avian, and one equine strain. Elucidation of the amino acid sequence of several human H2 receptor variants and analysis of known sequences of H2 and H3 isolates revealed that receptor specificity varies in association with an amino acid change at residues 228 in addition to the change at residue 226 previously documented to affect receptor specificity of H3 but not H1 isolates. Residues 226 and 228 are leucine and serine in human isolates, which preferentially bind sialic acid alpha 2,6-galactose beta 1,4-N-acetyl glucosamine (SA alpha 2,6Gal), and glutamine and glycine in avian and equine isolates, which exhibit specificity for sialic acid alpha-2,3-galactose beta-1,3-N-acetyl galactosamine (SA alpha 2,3Gal). The results demonstrate that the correlation of receptor specificity and species of origin is maintained across both H2 and H3 influenza virus serotypes and provide compelling evidence that influenza virus hosts exert selective pressure to maintain the receptor specificity characteristics of strains isolated from that species.
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Cook, R. G., & Tauro, T. L. (1999). Object-goal positioning influences spatial representation in rats. Anim. Cogn., 2(1), 55–62.
Abstract: Three tests investigated how the geometric relation between object/landmarks and goals influenced spatial choice behavior in rats. Two groups searched for hidden food in an object-filled circular arena containing 24 small poles. For the “Proximal” group, four distinct objects in a square configuration were placed close to four baited poles. For the “Distal” group, the identical configuration of objects was rotated 45° relative to the poles containing the hidden food. The Proximal group learned to locate the baited poles more quickly than the Distal group. Tests with removed and rearranged landmarks indicated that the two groups learned to use the objects differently. The results suggested that close proximity of objects to goals encouraged their use as beacons, while greater distance of objects from goals resulted in the global encoding of the geometric properties of the arena and the use of the objects as landmarks.
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Cook, R. G., Shaw, R., & Blaisdell, A. P. (2001). Dynamic object perception by pigeons: discrimination of action in video presentations. Anim. Cogn., 4(3), 137–146.
Abstract: Two experiments examined the discrimination by pigeons of relative motion using computer-generated video stimuli. Using a go/no-go procedure, pigeons were tested with video stimuli in which the camera's perspective went either “around” or “through” an approaching object in a semi-realistic context. Experiment 1 found that pigeons could learn this discrimination and transfer it to videos composed from novel objects. Experiment 2 found that the order of the video's frames was critical to the discrimination of the videos. We hypothesize that the pigeons perceived a three-dimensional representation of the objects and the camera's relative motion and used this as the primary basis for discrimination. It is proposed that the pigeons might be able to form generalized natural categories for the different kinds of motions portrayed in the videos.
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Cooper, J. J., & Mason, G. J. (1998). The identification of abnormal behaviour and behavioural problems in stabled horses and their relationship to horse welfare: a comparative review. Equine Vet J Suppl, (27), 5–9.
Abstract: Many behaviours in domestic animals, such as the 'stable vices' of horses, are treated because they are considered undesirable for economic or cultural reasons, and not because the activity affects the horse's quality of life. The impact of a behaviour on the human reporter is not a function of its impact on the animal performer, and an understanding of the causes and effects of the particular activity is necessary to assess the costs and benefits of treatment. Where the behaviour is a sign of poor welfare, such as an inadequate environment, treatment can best be achieved by removing these underlying causal factors. Pharmacological or physical prevention of a behaviour can be justified only if the behaviour causes harm to the performer or to others. In these cases, prevention of the behaviour without addressing its causes is no cure and may result in its perseverance in a modified form or the disruption of the animal's ability to adapt to its environment. Where the behavioural 'problem' causes no harm and is not related to poor housing, then the education of the reporter, rather than treatment of the performer, may be the best solution.
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Couzin, I. D., Krause, J., James, R., Ruxton, G. D., & Franks, N. R. (2002). Collective Memory and Spatial Sorting in Animal Groups. J. Theor. Biol., 218(1), 1–11.
Abstract: We present a self-organizing model of group formation in three-dimensional space, and use it to investigate the spatial dynamics of animal groups such as fish schools and bird flocks. We reveal the existence of major group-level behavioural transitions related to minor changes in individual-level interactions. Further, we present the first evidence for collective memory in such animal groups (where the previous history of group structure influences the collective behaviour exhibited as individual interactions change) during the transition of a group from one type of collective behaviour to another. The model is then used to show how differences among individuals influence group structure, and how individuals employing simple, local rules of thumb, can accurately change their spatial position within a group (e.g. to move to the centre, the front, or the periphery) in the absence of information on their current position within the group as a whole. These results are considered in the context of the evolution and ecological importance of animal groups.
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Cox, G., & Ashford, T. (1998). Riddle Me This: The Craft and Concept of Animal Mind. Science Technology Human Values, 23(4), 425–438.
Abstract: This article examines the relations between methods used in both animal work and study and concepts of animal mind. By “animal work” the authors mean humans and animals working together, and by “animal study” they mean the discipline of ethology, especially the emerging area of cognitive ethology. Within these areas the wide range of conceptions of animal mind includes varying emphases on intelligence, forms of rationality and language, cognition, consciousness, and intentionality. The authors' central concern is to elucidate the vocabulary and the concepts which seem necessary to establishing successful working relationships with sheepdogs and gundogs. Their argument moves toward an emphasis on the appreciation of particular intentional states and recognizes that they invariably deploy elements of a moral vocabulary in achieving creative teamwork performances with dogs and other animals. The article concludes by consid enng the relevance of accounts of work with animals for associated considerations of intentionality.
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Crosby, M. B., Svenson, J. L., Zhang, J., Nicol, C. J., Gonzalez, F. J., & Gilkeson, G. S. (2005). Peroxisome proliferation-activated receptor (PPAR)gamma is not necessary for synthetic PPARgamma agonist inhibition of inducible nitric-oxide synthase and nitric oxide. J Pharmacol Exp Ther, 312(1), 69–76.
Abstract: Peroxisome proliferation-activated receptor (PPAR)gamma agonists inhibit inducible nitric-oxide synthase (iNOS), tumor necrosis factor-alpha, and interleukin-6. Because of these effects, synthetic PPARgamma agonists, including thiazolidinediones, are being studied for their impact on inflammatory disease. The anti-inflammatory concentrations of synthetic PPARgamma agonists range from 10 to 50 microM, whereas their binding affinity for PPARgamma is in the nanomolar range. The specificity of synthetic PPARgamma agonists for PPARgamma at the concentrations necessary for anti-inflammatory effects is thus in question. We report that PPARgamma is not necessary for the inhibition of iNOS by synthetic PPARgamma agonists. RAW 264.7 macrophages possess little PPARgamma, yet lipopolysaccharide (LPS)/interferon (IFN)gamma-induced iNOS was inhibited by synthetic PPARgamma agonists at 20 microM. Endogenous PPARgamma was inhibited by the transfection of a dominant-negative PPARgamma construct into murine mesangial cells. In the transfected cells, synthetic PPARgamma agonists inhibited iNOS production at 10 microM, similar to nontransfected cells. Using cells from PPARgamma Cre/lox conditional knockout mice, baseline and LPS/IFNgamma-induced nitric oxide levels were higher in macrophages lacking PPARgamma versus controls. However, synthetic PPARgamma agonists inhibited iNOS at 10 microM in the PPARgamma-deficient cells, similar to macrophages from wild-type mice. These results indicate that PPARgamma is not necessary for inhibition of iNOS expression by synthetic PPARgamma agonists at concentrations over 10 microM. Intrinsic PPARgamma function, in the absence of synthetic agonists, however, may play a role in inflammatory modulation.
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Crosby, M. B., Zhang, J., Nowling, T. M., Svenson, J. L., Nicol, C. J., Gonzalez, F. J., et al. (2006). Inflammatory modulation of PPAR gamma expression and activity. Clin Immunol, 118(2-3), 276–283.
Abstract: Nitric oxide (NO) production increases with age in the lupus-prone MRL/lpr mouse, paralleling disease activity. One mechanism for excess NO production in MRL/lpr mice may be a defect in down-regulatory mechanisms of the iNOS pathway. A potential modulator of NO is the nuclear hormone receptor peroxisome proliferation activated receptor gamma (PPARgamma). We demonstrate that renal PPARgamma protein expression was altered as disease progressed in MRL/lpr mice, which paralleled increased iNOS protein expression. Additionally, MRL/lpr-derived primary mesangial cells expressed less PPARgamma than BALB/c mesangial cells and produced more NO in response to LPS and IFNgamma. Furthermore, PPARgamma activity was reduced in mesangial cells following exposure to inflammatory mediators. This activity was restored with the addition of a NOS enzyme inhibitor. These results indicate that the activation of inflammatory pathways may lead to reduced activity and expression of PPARgamma, further exacerbating the disease state.
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Czerlinski, G. H., Erickson, J. O., & Theorell, H. (1979). Chemical relaxation studies on the horse liver alcohol dehydrogenase system. Physiol Chem Phys, 11(6), 537–569.
Abstract: Chemical relaxation studies on the system horse liver alcohol dehydrogenase, nicotinamide adenine dinucleotide, and ethanol were conducted observing fluorescence changes between 400 and 500 nm. Temperature-jump experiments were performed at pH 6.5, 7.0, 8.0, and 9.0; concentration-jump experiments at pH 9.0. The reciprocal of the slowest relaxation time was found to be linearly dependent upon the enzyme concentration for relatively low enzyme concentrations, as predicted earlier. Use of the wide pH-range necessitated expression of the four apparent dissociation constants of the catalytic reaction cycle in terms of pH-independent constants. The system was described in terms of only one (or two) catalysis-linked protons not associated with the electron transfer. Protonic steps in a buffered system are in rapid equilibrium, too fast to be measured with the equipment available. Assuming only two of the four bimolecular reaction steps in the four-step cycle are fast compared to the remaining two, six cases may be considered with six expressions for the reciprocal of the slowest relaxation time. Comparison with the experimental data revealed that the bimolecular reaction steps governing the slowest relaxation time change with pH. Above the effective time resolution of the temperature-lump instrument with fluorescence detection (0.1 msec) only one other relaxation time was detectable and only at pH 9. This relaxation time, found to be independent of the concentration of all reactants within experimental error (r = 10 +/- 5 msec), is most likely due to an interconversion among ternary complexes.
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Czerlinski, G. H., Wagner, M., Erickson, J. O., & Theorell, H. (1975). Chemical relaxation studies on the system liver alcohol dehydrogenase, NADH and imidazole. Acta Chem Scand B, 29(8), 797–810.
Abstract: Several years ago, Theorell and Czerlinski conducted experiments on the system of horse liver alcohol dehydrogenase, reduced nicotinamide adenine dinucleotide and imidazole, using the first version of the temperature jump apparatus with detection of changes in fluorescence. These early experiments were repeated with improved instrumentation and confirmed the early experiments in general terms. However, the improved detection system allowed to measure a slight concentration dependence of the relaxation time of around 3 ms. Furthermore, the chemical relaxation time was smaller than the one determined earlier (by factor 2). The data were evaluated much more rigorously than before, allowing an appropriate interpretation of the results. The observed relaxation time is largely due to rate constants in an interconversion of ternary complexes, which are faster than three (of the four) dissociation rate constants, determined previously by Theorell and McKinley-McKee.1,2 This fact contributed to earlier difficulties of finding any concentration dependence. However, the binding of imidazole to the binary enzyme-coenzyme complex can be made to couple kinetically into the interconversion rate of the two ternary complexes. The observed signal derives largely from the ternary complex(es). A substantial fluorescence signal change is associated with the observed relaxation process, suggesting a relocation of the imidazole in reference to the nicotinamide moiety of the bound coenzyme. Nine models are considered with two types of coupling of pre-equilibria (none-all). Quantitative evaluations favor the model with two ternary complexes connected by an interconversion outside the four-step (bimolecular) cycle. The ternary complex outside the cycle has much higher fluorescence yield than the one inside. The interconversion equilibrium is near unity for imidazole. If it would be shifted very much to the side of the “dead-end” complex (as in isobutyramide?!), stimulating action could not take place.
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