Influence of season, age, sex, and time of day on the endocrine profile of the common bottlenose dolphin (Tursiops truncatus).

Understanding baseline hormone levels, the magnitude of intra-individual variability, and their variation as a function of life history is difficult in toothed whales (e.g. dolphins and porpoises) because of the effects of capture stress. To determine the endocrine profile of the common bottlenose dolphin (Tursiops truncatus) as a function of season, time of day (TOD), age, sex, and reproductive status, blood corticosteroids, thyroid hormones, and catecholamines were repeatedly measured in a managed-care population exposed to ambient light and water temperatures of San Diego Bay. Additionally, fecal hormone metabolites were assessed for cortisol, aldosterone, and triiodothyronine. Samples were collected at two to four-week intervals over a period of two years, and multiple times within a day at monthly intervals over a year. Samples were collected through the voluntary participation of the dolphins in the blood draws and fecal collections in order to avoid the effects of handling stress. All serum hormones except aldosterone significantly varied with season and all serum hormones except total thyroxine significantly varied as a function of TOD. Fecal glucocorticoid metabolites significantly correlated with circulating cortisol levels, and there was a significant seasonal effect on triiodothyronine fecal metabolites. Strong seasonal effects demonstrated complex interactions with age and sex suggesting that contextual information is critical to interpreting differences in endocrine profiles. Strong circadian patterns further suggest that sampling design is important to the interpretation of blood or fecal collections, particularly since diurnal changes in some serum hormone levels are similar to the magnitude of seasonal differences. Despite potential impacts of feeding schedules on diurnal patterns, managed care populations can provide important insights into seasonal and age-related endocrine changes in toothed whales.

Blubber transcriptome response to acute stress axis activation involves transient changes in adipogenesis and lipolysis in a fasting-adapted marine mammal.

Stress can compromise an animal's ability to conserve metabolic stores and participate in energy-demanding activities that are critical for fitness. Understanding how wild animals, especially those already experiencing physiological extremes (e.g. fasting), regulate stress responses is critical for evaluating the impacts of anthropogenic disturbance on physiology and fitness, key challenges for conservation. However, studies of stress in wildlife are often limited to baseline endocrine measurements and few have investigated stress effects in fasting-adapted species. We examined downstream molecular consequences of hypothalamic-pituitary-adrenal (HPA) axis activation by exogenous adrenocorticotropic hormone (ACTH) in blubber of northern elephant seals due to the ease of blubber sampling and its key role in metabolic regulation in marine mammals. We report the first phocid blubber transcriptome produced by RNAseq, containing over 140,000 annotated transcripts, including metabolic and adipocytokine genes of interest. The acute response of blubber to stress axis activation, measured 2 hours after ACTH administration, involved highly specific, transient (lasting <24 hours) induction of gene networks that promote lipolysis and adipogenesis in mammalian adipocytes. Differentially expressed genes included key adipogenesis factors which can be used as blubber-specific markers of acute stress in marine mammals of concern for which sampling of other tissues is not possible.

Prophylaxis against central vein thrombosis with low-dose warfarin.

Low-dose warfarin was given to patients to prevent venous thrombosis. Patients at greatest risk for having thrombi adjacent to central venous catheters were detected by the von Kaulla assay. Patients with normal von Kaulla assays had one thrombus per 1844 days at risk while those with accelerated von Kaulla assays had one thrombus per 500 days at risk. Low-dose warfarin therapy given to patients at high risk reduced the incidence of venous thrombosis from one thrombus per 251 days to one thrombus per 1617 days. Thus low doses of warfarin that do not prolong the prothrombin time appear to offer prophylaxis against venous thrombosis in patients at high risk for developing venous thrombosis adjacent to the central venous catheters.

Periodic reassessment for improved, cost-effective care in home total parenteral nutrition: a case report.

Home parenteral nutrition (HPN) patients need periodic reassessment for compliance, appropriateness of parenteral formulation, infusion regimen, bowel adaptation, and effective oral nutrient intake. Additionally, new technological advances need to be considered for potential use in the home parenteral nutrition population. Since costs for home parenteral nutrition therapy are substantial, cost-effective options should be exercised whenever reasonable. The following case illustrates our approach to the reassessment process, subsequent modifications, and resultant impact on the lifestyle, adequacy, and cost of home parenteral nutrition therapy.

Suboptimal selenium status in home parenteral nutrition patients with small bowel resections.

The selenium status of 13 adult home parenteral nutrition (HPN) patients was evaluated using 12 healthy adult volunteers as controls. Patients had been maintained on HPN for a mean of 36 months and averaged 121 cm of residual small bowel. Prospective diet surveys in patients indicated a mean oral caloric intake of 902 kcal/day. The mean plasma selenium concentrations (microgram/g) were 0.044 in patients and 0.117 in controls (p less than 0.01). The erythrocyte glutathione peroxidase activities, as mumol of NADPH oxidized/g hemoglobin/min, averaged 11.01 in patients and 31.76 in controls (p less than 0.01). Four patients exhibited myalgic symptomatology suggestive of clinical selenium deficiency. No correlations could be ascertained between plasma selenium levels and glutathione peroxidase activities in either patients or controls. Additionally, in the patient group, no significant correlations could be ascertained between selenium status and oral caloric intake, residual small bowel length, symptomatology suggestive of deficiency or HPN duration. However, since sample size was not large, lack of correlations might best be considered suggestive not conclusive. The data indicate that HPN patients with small bowel resections exhibit suboptimal selenium status and may be at risk of developing clinically evident selenium deficiency. HPN patients should be prophylactically supplemented with selenium regardless of oral intake, duration of HPN, or residual length of resected small bowel.

Utilizing selenious acid to reverse selenium deficiency in total parenteral nutrition patients.

The ability of selenious acid to reverse selenium deficiency in eight adult home TPN patients was assessed. Initially, deficiency was documented by comparing both plasma selenium levels in patients (means = 0.035 micrograms/g) to those of 10 controls (means = 0.117 micrograms/g) (p less than 0.001) and by comparing erythrocyte glutathione peroxidase (GSHPx) activity, as mumol NADPH oxidized/g Hb/min, in patients (means = 8.93) to controls (means = 31.76) (p less than 0.002). Subsequently, patients added 100 micrograms/day of selenious acid to their total parenteral nutrition solutions. Postsupplementation selenium status demonstrated a mean plasma level of 0.101 micrograms/g and a mean erythrocyte GSHPx activity of 17.56. Statistically, patients' plasma selenium levels were significantly different (p less than 0.001) when compared to pretreatment levels. Additionally, there was no significant difference between the restored levels and the levels of the controls. Postsupplementation erythrocyte GSHPx activity (means = 17.56) was not significantly different from the initial patient values, although activity did double. Additionally, there existed a significant difference between the postsupplementation enzyme activity and the controls (p less than 0.03). We conclude that selenious acid is able to normalize deficient plasma levels but not deficient erythrocyte GSHPx activity.

Delayed cutaneous hypersensitivity response in patients receiving nutritional support.

The sensitivity and specificity of skin-test antigens were assessed, and the prevalence of anergy was determined in a group of hospitalized patients receiving aggressive nutritional therapy. All patients referred to a nutritional support service during a nine-month period were assessed for intact cellular immunity using Candida albicans, mumps, streptokinase/streptodornase, and tetanus toxoid skin tests for delayed cutaneous hypersensitivity. Some patients were retested at two-week intervals while they were receiving nutritional support. A total of 195 patients (97 men) ranging from 15 to 92 years old were tested; 68 patients received repeat skin tests. Of the 195 patients, 181 (92.8%) reacted positively to one or more antigens when tested initially; all patients (including anergic ones) who were retested reacted positively. Candida and mumps tests produced the highest percentages of positive responses (80 and 75%, respectively); the use of these two antigens concurrently produced a 92.3% response rate. Nonresponding patients to a nonresponding antigen converted to responders to that antigen upon second testing more frequently than responders converted to nonresponders. Candida and mumps skin tests detected anergy and demonstrated that immune responses were maintained and often restored by aggressive nutritional support.