Publications by authors named "Greta Doden"

3 Publications

  • Page 1 of 1

A RETROSPECTIVE SURVEY OF NEOPLASIA IN MANAGED GIRAFFES ().

J Zoo Wildl Med 2021 Apr;52(1):332-336

College of Veterinary Medicine, University of Illinois at Urbana-Champaign, Urbana, IL 61802, USA,

Giraffes () are commonly managed in zoos and conservation programs worldwide, but the current understanding of the occurrence and progression of neoplastic disease in this species is limited by the scarcity of published reports. This study collated documented cases of neoplasia on the basis of gross and histologic evaluation of ante- and postmortem samples. In total, 30 giraffes from 22 institutions across the United States were included. Subspecies was not reported in all cases, but those identified included Masai (), Rothschild (), and reticulated subspecies (). Thirteen animals died natural deaths, 15 were euthanized, and 2 were alive at the time of this article. A total of 38 tumors were reported and classified as 18 different diagnoses, including leiomyoma (7), adenoma (4), luteoma (4), lymphoma (4), pheochromocytoma (3), squamous cell carcinoma (3), adenocarcinoma (2), ameloblastic fibroma (1), carcinomatosis of undetermined cell lineage (1), cavernous hemangioma (1), cystic granulosa cell tumor (1), dysgerminoma (1), fibrosarcoma (1), leukemia (1), lipoma (1), pituitary nerve sheath tumor (1), rhabdomyosarcoma (1), and teratoma (1). Multiple concurrent neoplastic lesions were documented in six cases. Mesenchymal tumors (18) were the majority of neoplasms. The most prevalent location, regardless of tumor type, was the female reproductive tract (14). Twenty-four neoplastic lesions were incidental findings at necropsy, whereas eight neoplasms were considered to be the primary cause of death. The findings reported here identify multiple neoplastic lesions in giraffes and could provide insight to the future management of this species.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1638/2020-0100DOI Listing
April 2021

COMPARING THE EFFECTS OF LITHIUM HEPARIN AND DIPOTASSIUM ETHYLENEDIAMINETETRAACETIC ACID ON HEMATOLOGIC VALUES IN EASTERN BOX TURTLES ().

J Zoo Wildl Med 2021 Jan;51(4):999-1006

Wildlife Epidemiology Laboratory, College of Veterinary Medicine, University of Illinois, Urbana, IL 61802, USA,

Anticoagulants are employed to prevent clotting and preserve cellular morphology for clinical pathology tests. Lithium heparin (LH) is the most frequently used anticoagulant in chelonians; however, dipotassium ethylenediaminetetraacetic acid (EDTA) may be superior in some species. Although eastern box turtles' () hematologic parameters are well studied, the effects of different anticoagulants on hematology in this species are unknown. This study evaluated the effects of LH and EDTA on hematologic values in free-living eastern box turtles ( = 59). Blood samples were collected from eastern box turtles in Illinois and immediately divided between LH and EDTA microtainers, and complete blood counts were performed on each sample. Grossly, plasma from EDTA blood samples was frequently and significantly hemolyzed. Blood mixed with LH had higher packed cell volume (PCV) ( = 0.04), white blood cell count (WBC) determined by Leukopet ( < 0.0001), WBC determined by blood film estimate ( < 0.0001), absolute heterophils ( = 0.007), absolute lymphocytes ( < 0.0001), and lower total solids ( < 0.0001) and absolute monocytes ( = 0.0001) than blood mixed with EDTA. All relative leukocyte counts were significantly different between the anticoagulants ( < 0.0001). EDTA apparently lysed turtle erythrocytes in this study, making it difficult to accurately count white blood cells and artificially lowering PCV. These findings demonstrate that EDTA should not be used in eastern box turtles.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1638/2020-0109DOI Listing
January 2021

Metabolism of Oxo-Bile Acids and Characterization of Recombinant 12α-Hydroxysteroid Dehydrogenases from Bile Acid 7α-Dehydroxylating Human Gut Bacteria.

Appl Environ Microbiol 2018 05 1;84(10). Epub 2018 May 1.

Microbiome Metabolic Engineering Theme, Carl R. Woese Institute for Genomic Biology, Urbana, Illinois, USA

Bile acids are important cholesterol-derived nutrient signaling hormones, synthesized in the liver, that act as detergents to solubilize dietary lipids. Bile acid 7α-dehydroxylating gut bacteria generate the toxic bile acids deoxycholic acid and lithocholic acid from host bile acids. The ability of these bacteria to remove the 7-hydroxyl group is partially dependent on 7α-hydroxysteroid dehydrogenase (HSDH) activity, which reduces 7-oxo-bile acids generated by other gut bacteria. 3α-HSDH has an important enzymatic activity in the bile acid 7α-dehydroxylation pathway. 12α-HSDH activity has been reported for the low-activity bile acid 7α-dehydroxylating bacterium ; however, this activity has not been reported for high-activity bile acid 7α-dehydroxylating bacteria, such as , , and Here, we demonstrate that these strains express bile acid 12α-HSDH. The recombinant enzymes were characterized from each species and shown to preferentially reduce 12-oxolithocholic acid to deoxycholic acid, with low activity against 12-oxochenodeoxycholic acid and reduced activity when bile acids were conjugated to taurine or glycine. Phylogenetic analysis suggests that 12α-HSDH is widespread among , in the family, and human gut 12α-HSDH activity has been established in the medically important bile acid 7α-dehydroxylating bacteria , , and Experiments with recombinant 12α-HSDHs from these strains are consistent with culture-based experiments that show a robust preference for 12-oxolithocholic acid over 12-oxochenodeoxycholic acid. Phylogenetic analysis identified novel members of the gut microbiome encoding 12α-HSDH. Future reengineering of 12α-HSDH enzymes to preferentially oxidize cholic acid may provide a means to industrially produce the therapeutic bile acid ursodeoxycholic acid. In addition, a cholic acid-specific 12α-HSDH expressed in the gut may be useful for the reduction in deoxycholic acid concentration, a bile acid implicated in cancers of the gastrointestinal (GI) tract.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1128/AEM.00235-18DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5930368PMC
May 2018