A total of 221 strains of staphylococci and 98 strains of micrococci isolated from the skins of Eastern gray squirrels, Southern flying squirrels, raccoons, opossums, squirrel monkeys, swine, sheep, horses, cattle, and dogs were characterized in a preliminary attempt to resolve their natural relationships and distribution in nature. Staphylococci demonstrating the widest host range included Staphylococcus xylosus and unnamed Staphylococcus sp. 3. Unnamed Staphylococcus sp. 2 was isolated only from sheep, Staphylococcus sp. 4 only from opossums, Staphylococcus sp. 5 only from squirrel monkeys, and Staphylococcus sp. 6 only from swine. The predominant species isolated from human skin, including S. epidermidis, S. hominis, S. haemolyticus, and S. capitis, were either not isolated or only rarely isolated from animal skin. Micrococcus varians was the predominant Micrococcus species isolated from animal skin. M. luteus was only occasionally isolated. M. lylae, M. sedentarius, M. roseus, M. kristinae, and M. nishinomiyaensis, species occasionally isolated from human skin, were not isolated from animal skin.

Aims Brain-derived Neurotrophic Factor (BDNF) is markedly decreased in heart failure patients. Both BDNF and its receptor, Tropomyosin Related Kinase Receptor (TrkB), are expressed in cardiomyocytes, however the role of myocardial BDNF signaling in cardiac pathophysiology is poorly understood. Here we investigated the role of BDNF/TrkB signaling in cardiac stress response to exercise and pathological stress. Methods and Results We found that myocardial BDNF expression was increased in mice with swimming exercise, but decreased in a mouse heart failure model and human failing hearts. Cardiac-specific TrkB knockout (cTrkB KO) mice displayed a blunted adaptive cardiac response to exercise, with attenuated upregulation of transcription factor networks controlling mitochondrial biogenesis/metabolism, including Peroxisome proliferator-activated receptor gamma coactivator 1 alpha (PGC-1α). In response to pathological stress (transaortic constriction, TAC), cTrkB KO mice showed an exacerbated heart failure progression. The downregulation of PGC-1α in cTrkB KO mice exposed to exercise or TAC resulted in decreased cardiac energetics. We further unraveled that BDNF induces PGC-1α upregulation and bioenergetics through a novel signaling pathway, the pleiotropic transcription factor Yin Yang 1 (YY1). Conclusion Taken together, our findings suggest that myocardial BDNF plays a critical role in regulating cellular energetics in the cardiac stress response.

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The electrophoretic mobilities of non-specific esterases in vertical polyacrylamide slab gels were determined for 184 strains of staphylococci, representing a total of 18 proposed species and subspecies. Markedly uniform esterase patterns were seen within species demonstrating a high degree of human host specificity, while those species demonstrating a wide host range were polytypic and often showed considerable polymorphism. The unique banding patterns found in several species indicate that this technique may serve as a valuable aid to existing taxonomic schemes. Starch gel electrophoresis of representative strains usually produced sharper esterase bands than were found with polyacrylamide electrophoresis. However, the additional molecular-sieving effect produced by the polyacrylamide gels differentiated esterases to a greater extent.

Vertical polyacrylamide slab gel electrophoresis was conducted for the catalase enzymes of representative strains of 18 proposed species and subspecies of the genus Staphylococcus. The catalase bands which resulted were predominantly monomorphic within each of the species and differences in catalase mobilities were observed between many of the species. The electrophoretic mobilities of the catalases were supportive to the scheme of classification used. Many strains of certain species demonstrated multiple catalase bands which are suggestive of multimolecular forms of the enzyme. Horizontal starch gel electrophoresis of representative strains of S. capitis produced catalase bands with relative mobilities that were different from those obtained with polyacrylamide electrophoresis, presumably due to a difference in molecular sieving between the gels.