Universal DNA methylation age across mammalian tissuesAke T. Lu, Zhe Fei, Amin Haghani et al.|Nature Aging|2023 Aging, often considered a result of random cellular damage, can be accurately estimated using DNA methylation profiles, the foundation of pan-tissue epigenetic clocks. Here, we demonstrate the development of universal pan-mammalian clocks, using 11,754 methylation arrays from our Mammalian Methylation Consortium, which encompass 59 tissue types across 185 mammalian species. These predictive models estimate mammalian tissue age with high accuracy (r > 0.96). Age deviations correlate with human mortality risk, mouse somatotropic axis mutations and caloric restriction. We identified specific cytosines with methylation levels that change with age across numerous species. These sites, highly enriched in polycomb repressive complex 2-binding locations, are near genes implicated in mammalian development, cancer, obesity and longevity. Our findings offer new evidence suggesting that aging is evolutionarily conserved and intertwined with developmental processes across all mammals.
Metabolic and respiratory derangements associated with death in cold-stunned Kemp's ridley turtles (Lepidochelys kempii): 32 cases (2005–2009)Krista A. Keller, Charles J. Innis, Michael F. Tlusty et al.|Journal of the American Veterinary Medical Association|2012 OBJECTIVE: To assess selected clinicopathologic variables at hospital admission (day 1) for cold-stunned Kemp's ridley turtles (Lepidochelys kempii) that died during the first 3 days after admission (nonsurvivors) and turtles that survived (survivors) and to determine the percentage change of each variable from day 1 to day of death (nonsurvivors) or to day 2 or 3 of hospitalization (survivors). DESIGN: Retrospective case-control study. Animals-64 stranded, cold-stunned Kemp's ridley turtles hospitalized from October 2005 through December 2009. PROCEDURES: Blood gas, pH, Hct, and selected biochemical values in blood samples determined on day 1 and day of death (nonsurvivors; n = 32) or day 2 or 3 of hospitalization (survivors; 32) were obtained from medical records. For each variable, initial values and percentage changes (from initial values to values at the day of death or day 2 or 3 of hospitalization) were compared between survivors and nonsurvivors. RESULTS: Compared with blood analysis findings for survivors, nonsurvivors initially had significantly higher potassium concentration and Pco(2) and significantly lower Po(2), pH, and bicarbonate concentration than did survivors. For the first 2 or 3 days of hospitalization, percentage changes in potassium, lactate, and ionized calcium concentrations were significantly higher and percentage changes in pH and plasma glucose and bicarbonate concentrations were significantly lower in nonsurvivors. CONCLUSIONS AND CLINICAL RELEVANCE: At hospital admission, cold-stunned Kemp's ridley turtles were affected by metabolic and respiratory derangements; severe derangements were associated with death. Evaluation of blood gas, pH, Hct, and selected clinicopathologic variables provided useful clinical and prognostic information during rehabilitation of cold-stunned Kemp's ridley turtles.
Diagnosis and management of Enterococcus spp infections during rehabilitation of cold-stunned Kemp's ridley turtles (Lepidochelys kempii): 50 cases (2006–2012)Charles J. Innis, Hillary Braverman, Julie M. Cavin et al.|Journal of the American Veterinary Medical Association|2014 OBJECTIVE: To evaluate clinical data for cold-stunned Kemp's ridley turtles (Lepidochelys kempii) with Enterococcus spp infections during rehabilitation. DESIGN: Retrospective case series. ANIMALS: 50 stranded cold-stunned Kemp's ridley turtles hospitalized between 2006 and 2012. PROCEDURES: Medical records for turtles from which Enterococcus spp were isolated were reviewed retrospectively, and clinical data, including morphometric data, body temperature at admission, physical examination findings, antimicrobial medication history, history of medications administered IV, environmental data, day of diagnosis, clinical signs at diagnosis, microbiological testing results, sources of positive culture results, hematologic and plasma biochemical data, cytologic and histopathologic results, radiographic findings, antimicrobial treatments, time to first negative culture result, treatment duration, results of subsequent cultures, and case outcome, were collated and analyzed. RESULTS: Enterococcus spp were isolated from bacteriologic cultures of blood, bone, joint, and respiratory tract samples and a skin lesion, with supporting evidence of infection provided by histopathologic, cytologic, and radiographic data. Positive culture results were associated with clinical problems such as lethargy, anorexia, and lameness. Most (34/43 [79%]) turtles for which an antemortem diagnosis was made survived with treatment and were released into the wild. CONCLUSIONS AND CLINICAL RELEVANCE: Cold-stunned Kemp's ridley turtles may be affected by serious Enterococcus spp infections during rehabilitation. Recognition and treatment of these infections are important for successful rehabilitation.
Coelioscopic orchiectomy can be effectively and safely accomplished in cheloniansCoelioscopic orchiectomy was performed in 27 male turtles (25 juvenile to adult red-eared sliders (Trachemys scripta elegans), one adult eastern painted turtle (Chrysems picta picta), and one juvenile male yellow-spotted Amazon River turtle (Podocnemis unifilis)). Orchiectomy was conducted under coelioscopic visualisation using ligation and transection of the mesorchium, or transection of the mesorchium with monopolar radiosurgical scissors. In 22 cases, bilateral orchiectomy was performed through a single incision; five turtles required bilateral incisions. All turtles recovered from anaesthesia. Nine turtles died within one year of surgery from conditions believed to be unrelated to surgery. One turtle was lost to follow-up. Seventeen turtles remain clinically healthy one to three years postoperatively. Coelioscopic orchiectomy provides a minimally invasive method for sterilisation of male chelonians and provides excellent visualisation during surgery. This technique is a useful model for the development of additional minimally invasive surgical techniques for chelonians.
Disseminated Fungal Infection in Two Species of Captive SharksDavid Marancik, Aimee L. Berliner, Julie M. Cavin et al.|Journal of Zoo and Wildlife Medicine|2011 In this report, two cases of systemic mycosis in captive sharks are characterized. These cases were progressive and ultimately culminated in terminal disease. Paecilomyces lilacinus, an uncommon pathogen in human and veterinary medicine, was associated with areas of necrosis in the liver, heart, and gill in a great hammerhead shark (Sphyrna mokarran). Fungal growth was observed from samples of kidney, spleen, spinal fluid, and coelomic cavity swabs. Dual fungal infection by Exophiala pisciphila and Mucor circinelloides was diagnosed in a juvenile zebra shark (Stegostoma fasciatum). Both fungi were present in the liver, with more severe tissue destruction associated with E. pisciphila. E. pisciphila also produced significant necrosis in the spleen and gill, while M. circinelloides was associated with only minimal tissue changes in the heart. Fungal cultures from liver, kidney, and spleen were positive for both E. pisciphila and M. circinelloides. Identification of P. lilacinus and M. circinelloides was based on colonial and hyphal morphology. E. pisciphila was identified by sequence analysis of the 28S rRNA D1/D2 region and the internal transcribed spacer (ITS) region between the 18S and 28S rRNA subunit. These cases, and a lack of information in the literature, highlight the need for further research and diagnostic sampling to further characterize the host-pathogen interaction between elasmobranchs and fungi.