Convergence of marine megafauna movement patterns in coastal and open oceans.

The extent of increasing anthropogenic impacts on large marine vertebrates partly depends on the animals' movement patterns. Effective conservation requires identification of the key drivers of movement including intrinsic properties and extrinsic constraints associated with the dynamic nature of the environments the animals inhabit. However, the relative importance of intrinsic versus extrinsic factors remains elusive. We analyze a global dataset of ∼2.8 million locations from >2,600 tracked individuals across 50 marine vertebrates evolutionarily separated by millions of years and using different locomotion modes (fly, swim, walk/paddle). Strikingly, movement patterns show a remarkable convergence, being strongly conserved across species and independent of body length and mass, despite these traits ranging over 10 orders of magnitude among the species studied. This represents a fundamental difference between marine and terrestrial vertebrates not previously identified, likely linked to the reduced costs of locomotion in water. Movement patterns were primarily explained by the interaction between species-specific traits and the habitat(s) they move through, resulting in complex movement patterns when moving close to coasts compared with more predictable patterns when moving in open oceans. This distinct difference may be associated with greater complexity within coastal microhabitats, highlighting a critical role of preferred habitat in shaping marine vertebrate global movements. Efforts to develop understanding of the characteristics of vertebrate movement should consider the habitat(s) through which they move to identify how movement patterns will alter with forecasted severe ocean changes, such as reduced Arctic sea ice cover, sea level rise, and declining oxygen content.

Stable isotope analyses reveal individual variability in the trophic ecology of a top marine predator, the southern elephant seal.

Identifying individuals' foraging strategies is critical to understanding the ecology of a species, and can provide the means to predict possible ecological responses to environmental change. Our study combines stable isotope analysis and satellite telemetry to study the variability in individual foraging strategies of adult female southern elephant seals (Mirounga leonina). Our hypothesis is that female elephant seals from the Western Antarctica Peninsula (WAP) display individual specialization in their diets. We captured adult female elephant seals (n = 56, 2005-2009) at Livingston Island (Antarctica), and instrumented them with SMRU-CTD satellite tags. We collected blood, fur, and vibrissae samples for δ(13)C and δ(15)N analyses. The mean values for all vibrissae were -21.0 ± 0.7‰ for δ(13)C, and 10.4 ± 0.8‰, for δ(15)N. The individual variability of δ(13)C (60%) was more important than the within-individual variability (40%) in explaining the total variance observed in our data. For δ(15)N, the results showed the opposite trend, with the within-individual variability (64%) contributing more to the total variance than the individual variability (36%), likely associated with the effect that the fasting periods have on δ(15)N values. Most individuals were specialists, as inferred from the low intra-individual variability of δ(13)C values with respect to the population variability, with half the individuals utilizing 31% or less of their available niche. We found eight different foraging strategies for these animals. Female elephant seals from the WAP are a diverse group of predators with individuals utilizing only a small portion of the total available niche, with the consequent potential to expand their foraging habits to exploit other resources or environments in the Southern Ocean.

A global cline in a colour polymorphism suggests a limited contribution of gene flow towards the recovery of a heavily exploited marine mammal.

Evaluating how populations are connected by migration is important for understanding species resilience because gene flow can facilitate recovery from demographic declines. We therefore investigated the extent to which migration may have contributed to the global recovery of the Antarctic fur seal (Arctocephalus gazella), a circumpolar distributed marine mammal that was brought to the brink of extinction by the sealing industry in the eighteenth and nineteenth centuries. It is widely believed that animals emigrating from South Georgia, where a relict population escaped sealing, contributed to the re-establishment of formerly occupied breeding colonies across the geographical range of the species. To investigate this, we interrogated a genetic polymorphism (S291F) in the melanocortin 1 receptor gene, which is responsible for a cream-coloured phenotype that is relatively abundant at South Georgia and which appears to have recently spread to localities as far afield as Marion Island in the sub-Antarctic Indian Ocean. By sequencing a short region of this gene in 1492 pups from eight breeding colonies, we showed that S291F frequency rapidly declines with increasing geographical distance from South Georgia, consistent with locally restricted gene flow from South Georgia mainly to the South Shetland Islands and Bouvetøya. The S291F allele was not detected farther afield, suggesting that although emigrants from South Georgia may have been locally important, they are unlikely to have played a major role in the recovery of geographically more distant populations.

Randomized trial showing equivalent efficacy of filgrastim 5 micrograms/kg/d and 10 micrograms/kg/d following high-dose chemotherapy and autologous bone marrow transplantation in high-risk lymphomas.

PURPOSE: To evaluate the effect of two filgrastim dosages after autologous bone marrow transplantation (ABMT) in patients with Hodgkin's disease (HD) and non-Hodgkin's lymphoma (NHL). PATIENTS AND METHODS: Eighty-six patients were enrolled onto a multicenter, randomized, open-label study. The study compared the efficacy and safety of two different doses of filgrastim, 5-microgram/kg/d subcutaneous (SC) bolus injection and 10-microgram/kg/d SC continuous infusion, starting on day 1 following ABMT. RESULTS: Both patient groups were well matched in terms of demography and disease. The results showed no statistical difference in the median time to reach an absolute neutrophil count (ANC) of 0.5 x 10(9)/L (11 days; P = .685) and no difference in the median duration of neutropenia (10 v 11 days, respectively; P = .567) between either dose of filgrastim. The incidence and duration of fever and neutropenic fever were the same in both groups. The number and mean duration of clinically and documented infections, duration of intravenous (IV) antibiotics, time to discharge from hospital, and tumor response also were similar in both groups. CONCLUSION: This study demonstrates that a dose of filgrastim 5 micrograms/kg/d administered as a daily SC bolus injection has a similar efficacy and safety profile compared with the 10-microgram/kg/d dose administered as a SC continuous infusion. The lower dose of filgrastim has potential cost-saving implications in terms of both the dose of drug administered and the ease of administration. Based on these findings, the recommended dose of filgrastim after ABMT should be 5 micrograms/kg/d.

Contaminated rabbit patellar tendon grafts. In vivo analysis of disinfecting methods.

In Part 1 of our study, 40 central-third bone-patellar tendon-bone grafts were harvested from 20 adult California White rabbits under strict sterile conditions. Ten grafts were placed directly into a thioglycolate broth, incubated, and subcultured; no growth was noted in any specimen. The next 6 grafts were contaminated 20 seconds each with 2 different species of coagulase-negative staphylococci. Organisms were grown with cultures obtained from an operating room floor during anterior cruciate ligament reconstruction. Marked growth of both species was noted in all 6 grafts within 24 hours. A subsequent 3 series of 8 grafts each were harvested sterilely, contaminated as described above, and soaked in 1 of 3 solutions 30 minutes before culture. Both 10% povidone-iodine and a triple-antibiotic solution (gentamicin, clindamycin, polymyxin) were 100% ineffective as both organisms grew; 4% chlorhexidine gluconate effectively decontaminated 8 grafts in all cases. Part 2 involved contamination of harvested grafts with 5 common, virulent organisms: Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa, Klebsiella pneumoniae, and Enterococcus faecalis. Elimination of all except Klebsiella pneumoniae was successful with 4% chlorhexidine gluconate alone for 8 grafts. Using a triple-antibiotic solution after chlorhexidine gluconate in 6 grafts eliminated this organism also.

Predicting Exercise Capacity in Angina Patients on Propranolol.

The equations from this study provide measures that can be obtained with minimum risk and can predict the effects of treatment in angina pectoris patients.

Aerobic dive limit: how often does it occur in nature?

Diving animals offer a unique opportunity to study the importance of physiological constraint in their everyday behaviors. An important component of the physiological capability of any diving animal is its aerobic dive limit (ADL). The ADL has only been measured in a few species. The goal of this study was to estimate the aerobic dive limit from measurements of body oxygen stores and at sea metabolism. This calculated ADL (cADL) was then compared to measurements of diving behavior of individual animals of three species of otariids, the Antarctic fur seal, Arctocephalus gazella, the Australian sea lion, Neophoca cinerea, and the New Zealand sea lion, Phocarctos hookeri. Antarctic fur seals dove well within the cADL. In contrast, many individuals of both sea lion species exceeded the cADL, some by significant amounts. Australian sea lions typically dove 1.4 times longer than the cADL, while New Zealand sea lions on average dove 1.5 times longer than the cADL. The tendency to exceed the cADL was correlated with the dive pattern of individual animals. In both Antarctic Fur Seals and Australian sea lions, deeper diving females made longer dives that approached or exceeded the cADL (P<0.01, r(2)=0.54). Australian and New Zealand sea lions with longer bottom times also exceeded the cADL to a greater degree. The two sea lions forage on the benthos while the fur seals feed shallow in the water column. It appears that benthic foraging requires these animals to reach or exceed their aerobic dive limit.

Effect of a conditioning program in patients taking propranolol for angina pectoris.

17 patients with stable angina pectoris due to coronary occlusive disease had serial graded exercise tests performed while on no medication, after treatment with propranolol and after an 8-week exercise reconditioning regimen while taking propranolol. The patient whose angina-free exercise capacity on beta-blockade is 2.5 METs or greater is likely to benefit from an exercise program.

The ontogeny of metabolic rate and thermoregulatory capabilities of northern fur seal, Callorhinus ursinus, pups in air and water.

Young pinnipeds, born on land, must eventually enter the water to feed independently. The aim of this study was to examine developmental factors that might influence this transition. The ontogeny of metabolic rate and thermoregulation in northern fur seal, Callorhinus ursinus, pups was investigated at two developmental stages in air and water using open-circuit respirometry. Mean in-air resting metabolic rate (RMR) increased significantly from 113+/-5 ml O(2 )min(-)(1) (N=18) pre-molt to 160+/-4 ml O(2 )min(-)(1) (N=16; means +/- s.e.m.) post-molt. In-water, whole-body metabolic rates did not differ pre- and post-molt and were 2.6 and 1.6 times in-air RMRs respectively. Mass-specific metabolic rates of pre-molt pups in water were 2.8 times in-air rates. Mean mass-specific metabolic rates of post-molt pups at 20 degrees C in water and air did not differ (16.1+/-1.7 ml O(2 )min(-)(1 )kg(-)(1); N=10). In-air mass-specific metabolic rates of post-molt pups were significantly lower than in-water rates at 5 degrees C (18.2+/-1.1 ml O(2 )min(-)(1 )kg(-)(1); N=10) and 10 degrees C (19.4+/-1.7 ml O(2 )min(-)(1 )kg(-)(1); N=10; means +/- s.e.m.). Northern fur seal pups have metabolic rates comparable with those of terrestrial mammalian young of similar body size. Thermal conductance was independent of air temperature, but increased with water temperature. In-water thermal conductance of pre-molt pups was approximately twice that of post-molt pups. In-water pre-molt pups matched the energy expenditure of larger post-molt pups while still failing to maintain body temperature. Pre-molt pups experience greater relative costs when entering the water regardless of temperature than do larger post-molt pups. This study demonstrates that the development of thermoregulatory capabilities plays a significant role in determining when northern fur seal pups enter the water.