Akinyi C Nyaoke

Publications of Akinyi C Nyaoke

• Pathologic and parasitologic findings of cold-stunned kemp's ridley sea turtles (lepidochelys kempii) stranded on cape cod, massachusetts, 2001-2006.

  Authors: Charles Innis, Akinyi C Nyaoke, C Rogers Williams, Bridget Dunnigan, Constance Merigo, Denise L Woodward, E Scott Weber, Salvatore Frasca

  Journal of wildlife diseases. 08/2009; 45(3):594-610.

  Necropsy reports for 28 stranded, cold-stunned Kemp's ridley sea turtles (Lepidochelys kempii) that died between 2001 and 2006 were reviewed retrospectively. Gross and microscopic lesions wereNecropsy reports for 28 stranded, cold-stunned Kemp's ridley sea turtles (Lepidochelys kempii) that died between 2001 and 2006 were reviewed retrospectively. Gross and microscopic lesions were compiled to describe the pathologic and parasitologic findings in turtles that were found freshly dead on the beach or that died within 48 hr of stranding. Anatomic lesions of varying severity were identified in each of the examined turtles and were identified in tissues of the alimentary, respiratory, integumentary, nervous and sensory, and urogenital systems in order of decreasing frequency. Necrotizing enterocolitis and bacterial or fungal pneumonia were the most frequently encountered lesions that were considered clinically significant. Parasites and parasitic lesions were identified primarily in tissues of the alimentary system and included intestinal cestodiasis and parasitic granulomas containing larval cestodes or nematodes. Postlarval cestodes were also found in the coelom of two turtles. In many cases, the extent and severity of lesions were judged to be insufficient to have solely caused mortality, suggesting that additional factors such as metabolic, respiratory, and electrolyte derangements; hypothermia; and drowning may be important proximate causes of death in cold-stunned turtles. Results of this study provide insight into pathologic conditions that may be of clinical relevance to rehabilitation efforts for cold-stunned sea turtles.

• Eastern equine encephalitis in a captive harbor seal (Phoca vitulina).

  Authors: Michael P McBride, Michele A Sims, Robert W Cooper, Akinyi C Nyaoke, Cheryl Cullion, Matti Kiupel, Salvatore Frasca, Naomi Forrester, Scott C Weaver, E Scott Weber

  Journal of zoo and wildlife medicine : official publication of the American Association of Zoo Veterinarians. 01/2009; 39(4):631-7.

  A 31-yr-old male, captive harbor seal (Phoca vitulina) was evaluated for a 48-hr period of anorexia followed by the onset of seizures. A prolonged seizure failed to respond to anticonvulsant therapyA 31-yr-old male, captive harbor seal (Phoca vitulina) was evaluated for a 48-hr period of anorexia followed by the onset of seizures. A prolonged seizure failed to respond to anticonvulsant therapy and the animal was euthanized. At necropsy, no significant gross lesions were identified. Reverse transcriptase-polymerase chain reaction testing of brain samples was positive for eastern equine encephalitis virus (EEEV) RNA, and serum was positive for anti-EEEV antibodies by plaque reduction neutralization. Histopathologic evaluation revealed severe and multifocal encephalitis with leptomeningitis, characterized by neutrophilic infiltrates in neuropil, neuronal necrosis, satellitosis, neuronophagia, and perivascular cuffs of lymphocytes, macrophages, and neutrophils. Additionally there was moderate, multifocal, adrenal cortical necrosis. Immunohistochemical staining for EEEV demonstrated viral antigen within necrotic neurons and glial cells. Virus was isolated from frozen brain tissue, sequenced for comparison to other strains, and determined to be a typical North American strain. EEEV should be included as a possible cause of neurologic disease in harbor seals with compatible signs located in geographic regions where vector transmission of EEEV is encountered.

• Chemokine and cytokine gene expression profiles in chickens inoculated with Mycoplasma gallisepticum strains Rlow or GT5.

  Authors: Javed Mohammed, Salvatore Frasca, Katharine Cecchini, Debra Rood, Akinyi C Nyaoke, Steven J Geary, Lawrence K Silbart

  Vaccine. 01/2008; 25(51):8611-21.

  Mycoplasma gallisepticum infection in chickens leads to tracheitis, airsacculitis, poor feed conversion and reduced egg production, resulting in considerable economic hardship on the poultryMycoplasma gallisepticum infection in chickens leads to tracheitis, airsacculitis, poor feed conversion and reduced egg production, resulting in considerable economic hardship on the poultry industry. The chemokines and cytokines responsible for recruitment, activation and proliferation of leukocytes in affected tissues have not been described. In the current study, chemokine and cytokine gene expression profiles were investigated in tracheas of chickens inoculated with M. gallisepticum strains R(low) (pathogenic) and GT5 (attenuated) at days 1, 4 and 8 post-inoculation. Expression of lymphotactin mRNA was higher in R(low)-inoculated chickens than GT5- or PBS-inoculated chickens, while CXCL13/BCA1 mRNA expression level was higher in both GT5- or R(low)-inoculated chickens than in PBS-inoculated controls on day 1 post-inoculation. However, both R(low) and GT5 strains induced a down-regulation in mRNA expression of CCL20, IL-1beta, IL-8 and IL-12p40 genes, with CCL20 and IL-12 mRNA levels remaining lower on days 4 and 8 post-inoculation. On day 4, R(low)-inoculated chickens exhibited significantly higher tracheal lesion scores and higher levels of lymphotactin, CXCL13, CXCL14, RANTES, MIP-1beta, IL-1beta and IFN-gamma mRNA compared to PBS-inoculated controls. The mRNA levels of these genes were also higher in R(low)-inoculated chickens that had moderate to severe tracheal lesion scores on day 8 post-inoculation. These results reflect the importance of lymphocyte and monocyte chemotactic factors in the development of tracheal lesions in chickens inoculated with M. gallisepticum strain R(low). Our data also suggest that M. gallisepticum may modulate the host response causing dramatic decreases in CCL20, IL-8 and IL-12 mRNA levels in GT5- or R(low)-inoculated chickens as early as one day post-inoculation.

• Chemokine and cytokine gene expression profiles in chickens inoculated with Mycoplasma gallisepticum strains Rlow or GT5

  Authors: Javed Mohammed, Salvatore Frasca, Katharine Cecchini, Debra Rood, Akinyi C. Nyaoke, Steven J. Geary, Lawrence K. Silbart

  Vaccine.

  Mycoplasma gallisepticum infection in chickens leads to tracheitis, airsacculitis, poor feed conversion and reduced egg production, resulting in considerable economic hardship on the poultryMycoplasma gallisepticum infection in chickens leads to tracheitis, airsacculitis, poor feed conversion and reduced egg production, resulting in considerable economic hardship on the poultry industry. The chemokines and cytokines responsible for recruitment, activation and proliferation of leukocytes in affected tissues have not been described. In the current study, chemokine and cytokine gene expression profiles were investigated in tracheas of chickens inoculated with M. gallisepticum strains Rlow (pathogenic) and GT5 (attenuated) at days 1, 4 and 8 post-inoculation. Expression of lymphotactin mRNA was higher in Rlow-inoculated chickens than GT5- or PBS-inoculated chickens, while CXCL13/BCA1 mRNA expression level was higher in both GT5- or Rlow-inoculated chickens than in PBS-inoculated controls on day 1 post-inoculation. However, both Rlow and GT5 strains induced a down-regulation in mRNA expression of CCL20, IL-1β, IL-8 and IL-12p40 genes, with CCL20 and IL-12 mRNA levels remaining lower on days 4 and 8 post-inoculation. On day 4, Rlow-inoculated chickens exhibited significantly higher tracheal lesion scores and higher levels of lymphotactin, CXCL13, CXCL14, RANTES, MIP-1β, IL-1β and IFN-γ mRNA compared to PBS-inoculated controls. The mRNA levels of these genes were also higher in Rlow-inoculated chickens that had moderate to severe tracheal lesion scores on day 8 post-inoculation. These results reflect the importance of lymphocyte and monocyte chemotactic factors in the development of tracheal lesions in chickens inoculated with M. gallisepticum strain Rlow. Our data also suggest that M. gallisepticum may modulate the host response causing dramatic decreases in CCL20, IL-8 and IL-12 mRNA levels in GT5- or Rlow-inoculated chickens as early as one day post-inoculation.