Publications by authors named "S B Petkova"

Human cytomegalovirus (HCMV) encodes four viral Fc-gamma receptors (vFcγRs) that counteract antibody-mediated activation in vitro, but their role in infection and pathogenesis is unknown. To examine their in vivo function in an animal model evolutionarily closely related to humans, we identified and characterized Rh05, Rh152/151 and Rh173 as the complete set of vFcγRs encoded by rhesus CMV (RhCMV). Each one of these proteins displays functional similarities to their prospective HCMV orthologs with respect to antagonizing host FcγR activation in vitro.

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The free radical nitric oxide (NO) and Ca are critical regulators of skeletal muscle exercise performance and fatigue. The major source of NO in skeletal muscle cells is the neuronal form of the enzyme Nitric oxide synthase (nNOS). One of the most peculiar characteristics of the Nurse cell of () is the complete loss of the contractile capabilities of its derivative striated muscle fiber.

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Human cytomegalovirus (HCMV) encodes four viral Fc-gamma receptors (vFcγRs) that counteract antibody-mediated activation , but their role in infection and pathogenesis is unknown. To examine the function of vFcγRs in animal hosts closely related to humans, we identified and characterized vFcγRs encoded by rhesus CMV (RhCMV). We demonstrate that Rh05, Rh152/151 and Rh173 represent the complete set of RhCMV vFcγRs, each displaying functional similarities to their respective HCMV orthologs with respect to antagonizing host FcγR activation .

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Hemocyanins are oxygen-transporting glycoproteins in the hemolymph of some invertebrate species that attracted scientific interest as potential anticancer agents. The present study aims to assess the and anticancer activity of hemocyanins isolated from , , and in the Graffi myeloid tumor model. The antitumor activity of the hemocyanins was determined by a MTT test and cytomorphological analysis by fluorescent and transmission electron microscopy.

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Sensory experiences in early development shape higher cognitive functions such as language acquisition in humans and song learning in birds. Zebra finches (Taeniopygia guttata) sequentially exposed to two different song 'tutors' during the sensitive period in development are able to learn from their second tutor and eventually imitate aspects of his song, but the neural substrate involved in learning a second song is unknown. We used fMRI to examine neural activity associated with learning two songs sequentially.

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