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Retinitis Pigmentosa (RP) is a genetically heterogeneous disorder characterized by rod and cone photoreceptor cell dysfunction. X-linked RP (XLRP) is one of the most severe forms of human retinal degeneration, as determined by age-of-set and progression, and accounts for six to 20 % of all RP cases. At least six XLRP loci have been identified, but RP3 is the major subtype of XLRP, accounting for 70 to 80 % of affected families. The RPGR gene is responsible for the RP3 form of XLRP and is mutated in 10–20 % of all RP patients. The pathogenesis of retinitis pigmentosa GTPase regulator (RPGR) mutant-causing RP is not clear, different animal models have been used to understand the pathogenesis of these diseases. In this brief review, we will summarize the functional characterization of RPGR and highlight recent studies in animal models, which will not only shed light on the disease mechanisms in XLRP but will also provide therapeutic strategies for RP treatment. [ABSTRACT FROM AUTHOR]

The inclusion of companion species with naturally occurring tumors provides significant opportunities for optimizing drug development pathways that other model systems cannot provide. Over the past decade, tremendous growth in the field of comparative oncology has occurred, including significant increases in organized consortium infrastructure, availability of investigational reagents and regulatory standardization. These advances are currently being applied to the development of novel cytotoxic, immunologic and biology-based anticancer therapies, innovative drug delivery systems, identification and validation of biological endpoints, noninvasive imaging techniques and surrogate markers critical to the design of Phase I and Phase II human clinical trials. The biotechnology and pharmaceutical industries recognize the utility of the model΄s inclusion and several examples exist where they have initiated studies in companion species to assist in drug development. We are clearly at a period in time where the microscope is turned on this model and while currently a theory, the next 5 or 10 years should determine the degree to which information generated through the inclusion of companion animals with cancer is applicable to human cancer drug development. [ABSTRACT FROM AUTHOR]

In the brain, oxidative damage, loss of synapses, and loss of growth factors such as brain-derived neurotrophic factor (BDNF) are linked to age-associated cognitive decline and Alzheimer΄s disease (AD). Antioxidant treatments to reduce oxidative damage have provided only modest benefits in human clinical trials. Cognitive and physical training, which may promote synapse growth and maintenance and increase BDNF, has proved to be more promising in small clinical trials in normal aged individuals and AD patients. Using a canine model of human brain aging, which naturally accumulates oxidative damage and cognitive dysfunction, we tested the hypothesis that combining treatments that can reduce several age-associated neuropathologies will prove to be more efficacious than targeting a single pathologic cascade. Aged beagles were either fed an antioxidant/mitochondrial cofactor diet (vitamins E and C, fruits and vegetables, lipoic acid and carnitine) or provided with behavioral enrichment that can increase BDNF and synapse and neuron growth (environmental, social, and cognitive enrichment with physical exercise) or treated with a combination of both the diet and behavioral enrichment. Cognitive improvements were observed for each treatment alone, but the combination approach, in particular, led to larger improvements in learning scores, to maintenance of cognitive ability, and to recovery of impaired memory function. Notably, each treatment selectively reduced different types of neuropathology in the brain. The use of a combination of antioxidant supplement or diet and other lifestyle modifications (increased social activity, physical activity, and cognitive engagement) may work additively and be beneficial for healthy human brain aging. [ABSTRACT FROM AUTHOR]

The need for appropriate animal models to conduct translational research is vital for advancements in the diagnosis and treatment of heart disease. The choice of animal model to be employed must be critically evaluated. In this chapter, we present the comparative cardiac anatomy of several of the commonly employed animal models (dog, pig, and sheep). A general comparison focuses on several specific anatomic features: the atria, the ventricles, the valves, the coronary system, lymphatics, and the conduction system. Finally, we present novel qualitative and quantitative data that we have obtained from perfusion fixed specimens of the most commonly used animal models. [ABSTRACT FROM AUTHOR]

Heterogeneous face images come from different lighting conditions or different imaging devices, such as visible light (VIS) and near infrared (NIR) based. Because heterogeneous face images can have different skin spectra-optical properties, direct appearance based matching is no longer appropriate for solving the problem. Hence we need to find facial features common in heterogeneous images. For this, first we use Difference-of-Gaussian filtering to obtain a normalized appearance for all heterogeneous faces. We then apply MB-LBP, an extension of LBP operator, to encode the local image structures in the transformed domain, and further learn the most discriminant local features for recognition. Experiments show that the proposed method significantly outperforms existing ones in matching between VIS and NIR face images. [ABSTRACT FROM AUTHOR]

Prebiotic supplementation of animal diets began in an attempt to increase concentrations of beneficial intestinal microbiota. It was understood that prebiotics inhibited growth of intestinal pathogens and decreased concentrations of stool odor-causing metabolites. Since the use of prebiotics began, several countries have banned the use of antimicrobials in livestock animal feeds, and several more have placed restrictions on the quantity of antimicrobials that can be used. Prebiotic supplementation has become increasingly popular as the body of evidence supporting its use continues to grow. As this literature expands, the number of potential prebiotic substances has grown beyond those that are naturally occurring, such as those found in chicory and yeast products, to include a large number of synthetic or chemically/enzymatically manufactured prebiotics. [ABSTRACT FROM AUTHOR]

The Status of Research Mystified about the origins and cultural development of the strange people they called los indios, the sixteenth-century Spanish conquerors of Mesoamerica could do little more than speculate. Native accounts of the past spoke of successive worldly creations and tribal migrations, but the conquistadores created their own explanatory narratives, founded for the most part in biblical lore and Classical mythology. Ranging from the insightful to the preposterous, these tales stood largely unverified until the latter part of the nineteenth century, when archaeologists first began the task of systematically investigating Mesoamerica's prehistory. Even then research was focused primarily on the more recent pottery-making periods. It is only since the 1950s that any significant headway has been made toward reconstructing the story of the very earliest human inhabitants of Mesoamerica or, for that matter, of the New World as a whole. What we can now say with reasonable certainty is that the prehistory of Mesoamerica begins more than 12,500 years ago, and perhaps as early as 35,000 years ago, with the initial entry into the New World of small bands of hunters and wild-food gatherers from northeast Asia. Adapting to the varied environmental challenges of their new homeland, these nomadic foragers flourished, so that by 9000 b.c. they extended from coast to coast and from the far north in Alaska to Tierra del Fuego at the tip of South America. Over the millennia, with an increasingly large and dense population to support and with the post-Pleistocene extinction of many of the animal species on which they had depended for food, the immigrants evolved new and more productive methods of subsistence, culminating in the development of agriculture and the domestication of maize, beans, squash, and the more than forty other cultigens that came to constitute the Mesoamerican diet. [ABSTRACT FROM AUTHOR]