Estropause, sex hormones and metal homeostasis in the mouse brain

Alterations in brain metal ion homeostasis have been reported with aging and are implicated in the pathogenesis of neurodegenerative diseases. To assess whether age-related changes in hypothalamic-pituitary-gonadal (HPG) hormones might be involved in modulating brain metal ion homeostasis, we treated 7.5-month intact, sham-ovariecomized and ovariectomized C57B6SJL mice with vehicle or leuprolide acetate (for 9-months) to differentiate between whether sex steroids or gonadotropins might modulate brain metal ion concentrations. Unlike other aging mammals, there was no increase in plasma luteinizing hormone (LH) and follicle-stimulating hormone (FSH) concentrations following estropause in mice, suggesting there was sufficient residual production by the follicle depleted ovary, of sex steroids like estrogens and protein hormones like the inhibins, in order to suppress pituitary LH/FSH production. Castration on the other hand induced significant increases in circulating LH and FSH. Modulation of plasma sex steroid and gonadotropin levels did not significantly alter the concentrations of brain metals tested (Fe, Zn, Cu, Mn, Co, Ni, Al, Li), although there was a tendency for a decrease in all brain metals following ovariectomy (low estrogens and progesterone, high gonadotropins), a response that was reversed with leuprolide acetate treatment (low sex steroids, low gonadotropins). Brain Cu concentration was the only metal correlated with plasma LH (−0.37, n = 30, p \u3c 0.05) and FSH (−0.42, n = 29, p \u3c 0.01). This study demonstrates that sex hormones do not markedly alter brain metal ion homeostasis, unlike previously reported studies of circulating metal ion homeostasis. The role of gonadotropins in regulating metal ion homeostasis does however warrant further study

Viral shedding of clade 2.3.4.4 H5 highly pathogenic avian influenza A viruses by American robins

American robins (Turdus migratorius) are commonly associated with farmsteads in the United States and have shown previous evidence of exposure to an H5 avian influenza A virus (IAV) near a poultry production facility affected by a highly pathogenic (HP) H5 virus in Iowa, USA during 2015. We experimentally infected American robins with three clade 2.3.4.4 HP H5 viruses (H5N2 and H5N8). A total of 22/24 American robins shed virus, and all three strains were represented. The highest virus titres shed were 104.3, 104.3 and 104.8 PFU/ml, associated respectively with viruses isolated from poultry, a captive gyrfalcon (Falco rusticolus), and a Northern pintail (Anas acuta). Of those birds that shed, viral shedding was initiated 1 or 2 days post‐infection (DPI) and shedding ceased in all birds by 7 DPI. This study adds an additional synanthropic wildlife species to a growing list of animals that can successfully replicate and shed IAVs

Viral shedding of clade 2.3.4.4 H5 highly pathogenic avian influenza A viruses by American robins

American robins (Turdus migratorius) are commonly associated with farmsteads in the United States and have shown previous evidence of exposure to an H5 avian influenza A virus (IAV) near a poultry production facility affected by a highly pathogenic (HP) H5 virus in Iowa, USA during 2015. We experimentally infected American robins with three clade 2.3.4.4 HP H5 viruses (H5N2 and H5N8). A total of 22/24 American robins shed virus, and all three strains were represented. The highest virus titres shed were 104.3, 104.3 and 104.8 PFU/ml, associated respectively with viruses isolated from poultry, a captive gyrfalcon (Falco rusticolus), and a Northern pintail (Anas acuta). Of those birds that shed, viral shedding was initiated 1 or 2 days post‐infection (DPI) and shedding ceased in all birds by 7 DPI. This study adds an additional synanthropic wildlife species to a growing list of animals that can successfully replicate and shed IAVs

Cottontail rabbits shed clade 2.3.4.4 H5 highly pathogenic avian influenza A viruses

During 2014-2015, clade 2.3.4.4 H5Nx highly pathogenic (HP) avian influenza A viruses (IAV) were first detected in North America and subsequently caused one of the largest agricultural emergencies in U.S. history. Recent evidence has suggested that cottontail rabbits can shed multiple IAV subtypes. We experimentally infected cottontail rabbits with three HP H5Nx IAVs. All rabbits tested shed virus on at least one day by at least one route. Cottontail rabbits appear to be an exception to the limited capacity for replication that has been previously reported for certain other mammalian species inoculated with clade 2.3.4.4 HP H5Nx avian influenza A viruses

Experimental Inoculation of Coyotes with \u3ci\u3eMycobacterium bovis\u3c/i\u3e Susceptibility and Shedding

Several wildlife species have tested positive for bovine tuberculosis in Michigan and may potentially transmit the disease to other animals. Coyotes have the highest known prevalence in the endemic area and thus, our objective was to investigate the shedding of Mycobacterium bovis by coyotes. Four coyotes were orally inoculated with 1 ml of 1 x 105 CFU/ml of M. bovis. Oral and nasal swabs, and feces were collected regularly and tested by culture. Fecal samples were also tested by exposing guinea pigs to the coyotes\u27 feces. All animals were necropsied to determine if infection occurred. All swabs, feces and tissues were negative on culture. The dosage of M. bovis given to these coyotes was considered biologically relevant, but was insufficient for causing infection. Due to the lack of infection, we still do not know the risk coyotes pose for shedding M. bovis

Initial Data and Coordinates for Multiple Black Hole Systems

We present here an alternative approach to data setting for spacetimes with multiple moving black holes generalizing the Kerr-Schild form for rotating or non-rotating single black holes to multiple moving holes. Because this scheme preserves the Kerr-Schild form near the holes, it selects out the behaviour of null rays near the holes, may simplify horizon tracking, and may prove useful in computational applications. For computational evolution, a discussion of coordinates (lapse function and shift vector) is given which preserves some of the properties of the single-hole Kerr-Schild form