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Invasive non-native species are widespread in freshwaters but their capacity to establish in new lakes has seldom been assessed. In this fouryear study (2006–2009), we used Side-scan Sonar and underwater video to illustrate how a 200 ha urban, amenity lake at Cardiff Bay (Wales, UK) was invaded extensively by zebra mussels Dreissena polymorpha (Pallas) within 2–3 years of creation in 2001. Veliger surveys and artificial substrates were used to assess conditions affecting juvenile settlement. Within 5–8 years of lake formation, all hard substrates at 0.5–7 m held mussel densities of 250–6600 m-2 which, coupled with a crude estimate of habitat available, suggested a lake-wide population of at least 9–31 million adults. Veligers reached 8 (± 2 SE) to 14 (± 4) L-1 during May–September when water temperatures were >14 °C, but densities and juvenile settlement declined at high discharge when lake flushing rates increased: settled densities in a drier year (2007) exceeded those in a wet year (2008) by 120× implying more effective colonisation under low flows and longer residence times. These data illustrate how rapid invasion by non-native species should be appropriately factored into planning and risk assessments for new water bodies, and potential effects on amenity, ecosystem processes and ecosystem services considered. Our data suggest that drought and low flow under future climates could be a particular risk factor affecting Dreissena colonisation. [ABSTRACT FROM AUTHOR]

Lymphocyte-depleting induction lowers acute rejection ( AR) rates among high-immunologic risk ( HIR) renal transplant recipients, including African Americans ( AAs), retransplants, and the sensitized. It is unclear whether different HIR subgroups experience similarly low rates of AR. We aimed to describe the incidence of AR and de novo donor-specific antibody (dn DSA) among HIR recipients categorized by age, race, or donor type. All received antithymocyte globulin ( ATG) induction and triple maintenance immunosuppression. A total of 464 HIR recipients from 2007 to 2014 were reviewed. AR and dn DSA rates at 1 year for the entire population were 14% and 27%, respectively. AR ranged from 6.7% among living donor ( LD) recipients to 30% in younger AA deceased donor ( DD) recipients. De novo donor-specific antibody at 1 year ranged from 7% in older non- AA LD recipients to 32% in AAs. AA race remained as an independent risk factor for AR among DD recipients and for dn DSA among all HIR recipients. Development of both AR and dn DSA within the first year was associated with a 54% graft survival at 5 years and was an independent risk factor for graft loss. Despite utilization of recommended immunosuppression for HIR recipients, substantial disparities exist among subgroups, warranting further consideration of individualized immunosuppression in certain HIR subgroups. [ABSTRACT FROM AUTHOR]

Objective: [2-18F] 2-fluorodeoxyglucose (FDG) is widely used to trace glucose metabolism for cardiac imaging with positron emission tomography. Because the transport and phosphorylation rates differ for glucose and FDG, a lumped constant (LC) is used to correct for these differences. The effects of ischemia and reperfusion on the LC in vivo are unknown. To determine the validity of FDG as a tracer of glucose metabolism in post-ischemic myocardium in vivo, the relationship between glucose uptake (GU) and FDG metabolic rate (FDG-MR) was assessed early post-reperfusion following a transient ischemic event. Methods: FDG metabolic rate, measured with FDG and PET, was compared to invasive measurements of substrate metabolism in reperfused and global myocardium of dogs subjected to 25 min ischemia and 2 h reperfusion. Results: The FDG metabolic rate was decreased 20±4% in reperfused relative to remote myocardium. Glucose oxidation and lactate uptake were also decreased in reperfused relative to global myocardium, by 26±6% and 60±8% respectively. Glucose uptake did not differ significantly between reperfused and global myocardium. A linear correlation between FDG metabolic rate and glucose uptake was found in both reperfused and remote myocardium. Estimates of the LC from the slopes of the regression lines were similar in reperfused and remote myocardium, 1.25 and 1.44 respectively, and did not differ significantly from the LC determined in control dogs, 1.1. Conclusions: We conclude that the FDG metabolic rate continues to correlate well with glucose metabolism in reperfused myocardium. While FDG metabolic rate was modestly decreased in the absence of a significant change in glucose uptake, large alterations in the LC are not found 2 h post-reperfusion in vivo. [ABSTRACT FROM PUBLISHER]

Objective: Myocardial reperfusion following brief periods of ischaemia is associated with prolonged, reversible periods of metabolic dysfunction. As the glycolytic enzyme glyceraldehyde-3-phosphate dehydrogenase (GAPDH) is inhibited in vitro by reactive oxygen species, we hypothesized that production of reactive oxygen species during reperfusion would lead to inhibition of GAPDH in post-ischaemic myocardium. Methods: Anaesthetized closed-chest dogs were subjected to 20 min balloon occlusion of the left anterior descending coronary artery. Biopsy samples were taken after 3 and 24 h of reperfusion, to determine the activity of GAPDH and the concentrations of glycolytic intermediates in post-ischaemic and remote, non-ischaemic territories. Results: A significant reduction in GAPDH activity was observed in post-ischaemic relative to remote tissue after 3 h reperfusion (4.8 ± 0.5 vs. 2.9 ± 0.2 μmol/min/mg protein; P < 0.01). Western blotting revealed no reduction in the levels of GAPDH protein. Analysis of enzyme kinetics showed the loss of activity to be associated with decreased Vmax (5.9 ± 0.5 vs. 3.2 ± 0.2 μmol/min/mg protein; P < 0.01) with no significant change in the Km for glyceraldehyde-3-phosphate (GAP). Incubation of the inhibited enzyme under both mild and strong reducing conditions failed to reactivate the enzyme. The acute reduction in enzyme activity in post-ischaemic tissue was accompanied by regional differences in glycolytic intermediates, notably a twofold accumulation of GAP (P < 0.05), and a reduction in the glucose metabolic rate (GMR) determined by positron emission tomography and [18F]2-fluorodeoxyglucose. By 24 h reperfusion, no regional differences in GAPDH activity, reaction Vmax or Km, GAP concentrations or GMR were detectable. Conclusions: These results suggest that inhibition of GAPDH activity may represent an important point at which glycolysis is limited during reperfusion, and further, that the mechanisms of enzyme inhibition do not involve simple oxidation or S-thiolation of critical active site thiol groups. [ABSTRACT FROM PUBLISHER]