Projections of climate-driven changes in tuna vertical habitat based on species-specific differences in blood oxygen affinity

Oxygen concentrations are hypothesized to decrease in many areas of the ocean as a result of anthropogenically driven climate change, resulting in habitat compression for pelagic animals. The oxygen partial pressure, pO(2), at which blood is 50% saturated (P-50) is a measure of blood oxygen affinity and a gauge of the tolerance of animals for low ambient oxygen. Tuna species display a wide range of blood oxygen affinities (i.e., P-50 values) and therefore may be differentially impacted by habitat compression as they make extensive vertical movements to forage on subdaily time scales. To project the effects of end-of-the-century climate change on tuna habitat, we calculate tuna P-50 depths (i.e., the vertical position in the water column at which ambient pO(2) is equal to species-specific blood P-50 values) from 21st century Earth System Model (ESM) projections included in the fifth phase of the Climate Model Intercomparison Project (CMIP5). Overall, we project P-50 depths to shoal, indicating likely habitat compression for tuna species due to climate change. Tunas that will be most impacted by shoaling are Pacific and southern bluefin tunas-habitat compression is projected for the entire geographic range of Pacific bluefin tuna and for the spawning region of southern bluefin tuna. Vertical shifts in P-50 depths will potentially influence resource partitioning among Pacific bluefin, bigeye, yellowfin, and skipjack tunas in the northern subtropical and eastern tropical Pacific Ocean, the Arabian Sea, and the Bay of Bengal. By establishing linkages between tuna physiology and environmental conditions, we provide a mechanistic basis to project the effects of anthropogenic climate change on tuna habitats

Community-based recruitment of patients with COPD into clinical research.

Identifying subjects for clinical trials is difficult and the evidence base for recruitment strategies is limited, particularly in the field of COPD. We compared the efficiency and patient characteristics of different community-based recruitment strategies during a non-commercial COPD trial in the UK. Recruiting from general practice COPD registers was less efficient and identified patients with significantly milder disease than recruiting through pulmonary rehabilitation and patient groups. We report our experience and propose that pulmonary rehabilitation and patient groups may represent an enriched pool of COPD patients to recruit into clinical trials

Effects of different antibiotic classes on airway bacteria in stable COPD using culture and molecular techniques: a randomised controlled trial

Long-term antibiotic therapy is used to prevent exacerbations of COPD but there is uncertainty over whether this reduces airway bacteria. The optimum antibiotic choice remains unknown. We conducted an exploratory trial in stable patients with COPD comparing three antibiotic regimens against placebo

Breast Cancer Presenting as Unilateral Arm Edema

CONTEXT: Symptomatic arm lymphedema as the presenting symptom of invasive breast carcinoma is a rare occurrence. DESIGN: We report a case of invasive breast cancer presenting with unilateral arm swelling. The patient was initially thought to have venous thrombosis. A thorough physical examination and a mammogram revealed the presence of breast cancer and associated subclinical axillary lymphadenopathy. CONCLUSION: Failure to recognize this presentation can lead to misdiagnosis or a significant delay in diagnosis and treatment

Modelling multiphase flow in vertical pipe using CFD method.

Investigations of gas-liquid-solid flows in large diameter vertical pipes are scarce and detailed three phase flow study is still required to understand the flow interactions. Further investigation using high fidelity modelling is thus necessary due to complex flow interactions of the phases. In this study, a Computational Fluid Dynamics (CFD) method is used to investigate multiphase gas-liquid-solid flow in vertical pipe. Firstly, an appropriate validated numerical simulation scheme for two phase gas-liquid flow using ANSYS Fluent has been used to simulate possible flow regime transitions in vertical pipe. The scheme could predict the various flow regimes spanning bubbly to annular flow without prior knowledge of the flow patterns. The scheme was further extended to investigate the impact of solid particles in the flow field. More importantly the impact of solid concentration on the flow regime development and sand deposition was investigated. The results showed that the particulate deposition is greatly influenced by the particle concentration. In addition, the regime transitions and development in gas-liquid flows are different than that of gas-liquid-solid flows

Targeted Retreatment of Incompletely Recovered Chronic Obstructive Pulmonary Disease Exacerbations with Ciprofloxacin. A Double-Blind, Randomized, Placebo-controlled, Multicenter, Phase III Clinical Trial

RATIONALE: COPD exacerbations are prone to non-recovery but there are no data about the effectiveness of retreatment on these prolonged events. We examined whether further therapy with ciprofloxacin for incompletely resolved COPD exacerbations prolonged the time until the next event. METHODS: This multi-centre randomised double-blind placebo-controlled trial studied retreatment with oral ciprofloxacin 500mg or matched placebo twice daily for 7 days in patients with GOLD stage II - IV COPD with persistent symptoms and/or serum C-reactive protein (CRP) ≥8mg/L initiated 14 (+/- 3) days after an index COPD exacerbation. The primary outcome was the time to the next exacerbation within a 90-day period. RESULTS: Of 826 patients screened at 4 centres, 144 eligible participants with incomplete recovery were randomised to receive ciprofloxacin (n=72) or placebo (n=72). 57% of patients in the ciprofloxacin group had experienced 1 or more exacerbations, compared to 53% in the placebo group. The median time to the next exacerbation was 32.5 days (IQR 13-50) in the placebo arm and 34 days (IQR 17-62) in the ciprofloxacin arm, which was not significantly different (adjusted hazard ratio = 1.07, 95% CI 0.68-1.68; p=0.76). No significant differences were seen in quality of life scores or lung function between treatment groups. CONCLUSION: In patients with persistent symptoms and/or raised CRP 14 days following a COPD exacerbation, an additional course of ciprofloxacin resulted in no additional benefit compared to placebo. This suggests that non-recovered exacerbations are not driven by ongoing bacterial infection and may potentially be targeted with anti-inflammatory therapy

Dispersal Routes and Habitat Utilization of Juvenile Atlantic Bluefin Tuna, Thunnus thynnus, Tracked with Mini PSAT and Archival Tags

Between 2005 and 2009, we deployed 58 miniature pop-up satellite archival tags (PSAT) and 132 implanted archival tags on juvenile Atlantic bluefin tuna (age 2–5) in the northwest Atlantic Ocean. Data returned from these efforts (n = 26 PSATs, 1 archival tag) revealed their dispersal routes, horizontal and vertical movements and habitat utilization. All of the tagged bluefin tuna remained in the northwest Atlantic for the duration observed, and in summer months exhibited core-use of coastal seas extending from Maryland to Cape Cod, MA, (USA) out to the shelf break. Their winter distributions were more spatially disaggregated, ranging south to the South Atlantic Bight, northern Bahamas and Gulf Stream. Vertical habitat patterns showed that juvenile bluefin tuna mainly occupied shallow depths (mean  = 5–12 m, sd  = 15–23.7 m) and relatively warm water masses in summer (mean  = 17.9–20.9°C, sd  = 4.2–2.6°C) and had deeper and more variable depth patterns in winter (mean  = 41–58 m, sd  = 48.9–62.2 m). Our tagging results reveal annual dispersal patterns, behavior and oceanographic associations of juvenile Atlantic bluefin tuna that were only surmised in earlier studies. Fishery independent profiling from electronic tagging also provide spatially and temporally explicit information for evaluating dispersals rates, population structure and fisheries catch patterns

Pathogenic huntingtin inhibits fast axonal transport by activating JNK3 and phosphorylating kinesin

Author Posting. © The Author(s), 2009. This is the author's version of the work. It is posted here by permission of Nature America for personal use, not for redistribution. The definitive version was published in Nature Neuroscience 12 (2009): 864-871, doi:10.1038/nn.2346.Selected vulnerability of neurons in Huntington’s disease (HD) suggests alterations in a cellular process particularly critical for neuronal function. Supporting this idea, pathogenic Htt (polyQ-Htt) inhibits fast axonal transport (FAT) in various cellular and animal HD models (mouse and squid), but the molecular basis of this effect remains unknown. Here we show that polyQ-Htt inhibits FAT through a mechanism involving activation of axonal JNK. Accordingly, increased activation of JNK was observed in vivo in cellular and animal HD models. Additional experiments indicate that polyQ-Htt effects on FAT are mediated by the neuron-specific JNK3, and not ubiquitously expressed JNK1, providing a molecular basis for neuron-specific pathology in HD. Mass spectrometry identified a residue in the kinesin-1 motor domain phosphorylated by JNK3, and this modification reduces kinesin-1 binding to microtubules. These data identify JNK3 as a critical mediator of polyQ-Htt toxicity and provides a molecular basis for polyQ-Htt-induced inhibition of FAT.This work was supported by 2007/2008 MBL summer fellowship to GM; an HDSA grant to GM; NIH grants MH066179 to GB; and ALSA, Muscular Dystrophy Association, and NIH (NS23868, NS23320, NS41170) grants to STB