Cyclic AMP Inhibits Secretion From Electroporated Human Neutrophils

It has long been known that Intracellular cAMP inhibits and cGMP enhances intact neutrophil function. However, these effects are modest and require relatively high concentrations of the cyclic nucleotides. We decided to re‐examine the effects of cyclic nucleotides on Ca2+‐induced secretion by electroporated cells. This system allowed us to bypass normal cell surface receptor‐ligand interactions as well as to directly expose the intracellular space to native cyclic nucleotides. We found that concentrations of cAMP as low as 3 μM inhibited Ca2+‐induced secretion; 30–300 μM cAMP was maximally inhibitory. cAMP was actually slightly more potent than dibutyryl cAMP, a membrane‐permeant derivative. In contrast, cGMP was only slightly stimulatory at 3 μM and modestly inhibitory at 300 μM; dibutyryl cGMP was ineffective. A more detailed investigation of the effects of cAMP showed that inhibition was only obtained in the presence of Mg2+. Half‐maximal inhibition by cAMP occurred at 10–30 μM. Inhibition by cAMP was achieved by shifting the Ca2+ dose‐response curve for secretion to the right; this was observed for the release of both specific granules (vitamin B12 binding protein) and azurophil granules (B‐glucuronidase). We previously showed that ATP could enhance Ca2+‐induced secretion in the presence of Mg2+, apparently by interacting with a cell surface purine receptor. However, increasing concentrations of ATP could not overcome inhibition by cAMP; this suggested that cAMP acted at some site other than the purine receptor. Inhibition by cAMP was also less apparent in the presence of the protein kinase C agonist phorbol myristate acetate (PMA), suggesting that the cyclic nucleotide did not produce systemic desensitization of the neutrophils. In summary, these results demonstrate that low, physiologically relevant concentrations of cAMP can modulate neutrophil responsiveness.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/141578/1/jlb0172.pd

Field testing an acoustic lighthouse : Combined acoustic and visual cues provide a multimodal solution that reduces avian collision risk with tall human-made structures

Billions of birds fatally collide with human-made structures each year. These mortalities have consequences for population viability and conservation of endangered species. This source of human-wildlife conflict also places constraints on various industries. Furthermore, with continued increases in urbanization, the incidence of collisions continues to increase. Efforts to reduce collisions have largely focused on making structures more visible to birds through visual stimuli but have shown limited success. We investigated the efficacy of a multimodal combination of acoustic signals with visual cues to reduce avian collisions with tall structures in open airspace. Previous work has demonstrated that a combination of acoustic and visual cues can decrease collision risk of birds in captive flight trials. Extending to field tests, we predicted that novel acoustic signals would combine with the visual cues of tall communication towers to reduce collision risk for birds. We broadcast two audible frequency ranges (4 to 6 and 6 to 8 kHz) in front of tall communication towers at locations in the Atlantic migratory flyway of Virginia during annual migration and observed birds’ flight trajectories around the towers. We recorded an overall 12–16% lower rate of general bird activity surrounding towers during sound treatment conditions, compared with control (no broadcast sound) conditions. Furthermore, in 145 tracked “at-risk” flights, birds reduced flight velocity and deflected flight trajectories to a greater extent when exposed to the acoustic stimuli near the towers. In particular, the 4 to 6 kHz stimulus produced the greater effect sizes, with birds altering flight direction earlier in their trajectories and at larger distances from the towers, perhaps indicating that frequency range is more clearly audible to flying birds. This “acoustic lighthouse” concept reduces the risk of collision for birds in the field and could be applied to reduce collision risk associated with many human-made structures, such as wind turbines and tall buildings

X-ray CT and multiphase flow characterization of a 'bio-grouted' sandstone core : the effect of dissolution on seal longevity

Microbially induced carbonate precipitation (MICP) is a novel method for controlling permeability in the subsurface with potential for sealing or reducing leakage from subsurface engineering works such as carbon sequestration reservoirs. The purpose of this research was to measure, at core scale, the change in reservoir permeability and capillary pressure due to MICP during seal formation, then to monitor the integrity of the seal when exposed to acidic groundwater capable of causing dissolution. The experiment was carried out with a Berea sandstone core mounted in a high pressure core holder within a medical X-ray CT scanner. Multiple full volume CT scans gave spatially resolved maps of the changing porosity and saturation states throughout the experiment. Porosity and permeability decreased with MICP whilst capillary pressure was increased. Dissolution restored much of the original porosity, but not permeability nor capillary pressure. This lead to the conclusion that injection pathways were coupled with carbonate precipitation hence preferential flow paths sealed first and transport of the dissolution fluid was limited. Provided a high enough reduction in permeability can be achieved over a substantial volume, MICP may prove to be a durable bio-grout, even in acidic environments such as a carbon sequestration reservoir

The curatorial consequences of being moved, moveable or portable: the case of carved stones

It matters whether a carved stone is moved, moveable or portable. This influences perceptions of significance and of form and nature – is it a monument or an artefact? This duality may in turn affect understanding and appreciation of the resource. It has implications for how and if carved stones can be legally protected, who owns them, where and how they are administered, and by whom. The complexities of the legislation mean that all too often this is also a grey area. This paper explores these curatorial issues and their impact

Heterologous prime-boost-boost immunisation of Chinese cynomolgus macaques using DNA and recombinant poxvirus vectors expressing HIV-1 virus-like particles

Background: There is renewed interest in the development of poxvirus vector-based HIV vaccines due to the protective effect observed with repeated recombinant canarypox priming with gp120 boosting in the recent Thai placebo-controlled trial. This study sought to investigate whether a heterologous prime-boost-boost vaccine regimen in Chinese cynomolgus macaques with a DNA vaccine and recombinant poxviral vectors expressing HIV virus-like particles bearing envelopes derived from the most prevalent clades circulating in sub-Saharan Africa, focused the antibody response to shared neutralising epitopes. Methods: Three Chinese cynomolgus macaques were immunised via intramuscular injections using a regimen composed of a prime with two DNA vaccines expressing clade A Env/clade B Gag followed by boosting with recombinant fowlpox virus expressing HIV-1 clade D Gag, Env and cholera toxin B subunit followed by the final boost with recombinant modified vaccinia virus Ankara expressing HIV-1 clade C Env, Gag and human complement protein C3d. We measured the macaque serum antibody responses by ELISA, enumerated T cell responses by IFN-gamma ELISpot and assessed seroneutralisation of HIV-1 using the TZM-bl beta-galactosidase assay with primary isolates of HIV-1. Results: This study shows that large and complex synthetic DNA sequences can be successfully cloned in a single step into two poxvirus vectors: MVA and FPV and the recombinant poxviruses could be grown to high titres. The vaccine candidates showed appropriate expression of recombinant proteins with the formation of authentic HIV virus-like particles seen on transmission electron microscopy. In addition the b12 epitope was shown to be held in common by the vaccine candidates using confocal immunofluorescent microscopy. The vaccine candidates were safely administered to Chinese cynomolgus macaques which elicited modest T cell responses at the end of the study but only one out of the three macaques elicited an HIV-specific antibody response. However, the antibodies did not neutralise primary isolates of HIV-1 or the V3-sensitive isolate SF162 using the TZM-bl b-galactosidase assay. Conclusions: MVA and FP9 are ideal replication-deficient viral vectors for HIV-1 vaccines due to their excellent safety profile for use in humans. This study shows this novel prime-boost-boost regimen was poorly immunogenic in Chinese cynomolgus macaques

Glycosaminoglycan profiles of repair tissue formed following autologous chondrocyte implantation differ from control cartilage

Currently, autologous chondrocyte implantation (ACI) is the most commonly used cell-based therapy for the treatment of isolated femoral condyle lesions of the knee. A small number of centres performing ACI have reported encouraging long-term clinical results, but there is currently a lack of quantitative and qualitative biochemical data regarding the nature of the repair tissue. Glycosaminoglycan (GAG) structure influences physiological function and is likely to be important in the long-term stability of the repair tissue. The objective of this study was to use fluorophore-assisted carbohydrate electrophoresis (FACE) to both quantitatively and qualitatively analyse the GAG composition of repair tissue biopsies and compare them with age-matched cadaveric controls. We used immunohistochemistry to provide a baseline reference for comparison. Biopsies were taken from eight patients (22 to 52 years old) 1 year after ACI treatment and from four cadavers (20 to 50 years old). FACE quantitatively profiled the GAGs in as little as 5 μg of cartilage. The pattern and intensity of immunostaining were generally comparable with the data obtained with FACE. In the ACI repair tissue, there was a twofold reduction in chondroitin sulphate and keratan sulphate compared with age-matched control cartilage. By contrast, there was an increase in hyaluronan with significantly shorter chondroitin sulphate chains and less chondroitin 6-sulphate in repair tissue than control cartilage. The composition of the repair tissue thus is not identical to mature articular cartilage

Discard Mortality of Sea Scallops Following Capture and Handling in the Sea Scallop Dredge Fishery - Final Report

The focus of sea scallop, Placopecten magellanicus, management over the past 20 years has been to encourage the harvest of larger animals. This has been accomplished through a series of management measures including gear modifications, effort controls, crew size limitations and spatial management to protect juvenile scallops. While these measures have been effective in reducing the harvest of small scallops, their capture does still occur. Central to fully understanding the impact of the fishery on the resource, is a comprehensive estimate of the non-harvest mortality associated with commercial operations. Non-harvest mortality can be broken down into a number of different processes, with discard mortality being a major category. Discard mortality (DM) is the rate of mortality associated with animals that are captured and subsequently released due to primarily market factors. The latest stock assessment for sea scallops assumes that 20% of all animals discarded will die. There is considerable uncertainty associated with this estimate that is based on a single older tagging study and studies examining a non-Placopecten species under different biotic and abiotic conditions

Communicating the Impacts of Potential Future Climate Change on the Expected Frequency of Extreme Rainfall Events in Cook County, Illinois

A novel methodology for determining future rainfall frequency is described in this report. Isohyetal maps illustrate how heavy precipitation may change in the future, but the results have a high level of uncertainty expressed as very wide confidence limits. Uncertainty in possible future conditions is much greater than the uncertainty identified for current commonly used precipitation analyses. The resulting isohyetal maps do not replace existing sources, such as Illinois State Water Survey (ISWS) Bulletin 70 (Huff and Angel, 1989) or National Oceanic and Atmospheric Administration (NOAA) Atlas 14 (Bonnin et al., 2006). Presently, the ISWS is updating Bulletin 70 (Huff and Angel, 1989) for subregions of Illinois. Some of these updates will include projected rainfall frequency. The key objectives of this study are to i) design a framework to translate future climate scenarios into a product that engineers and planners can use to quantify the impact of climate change, and ii) demonstrate how climate model output can be used to inform and plan adaptive strategies for stormwater and floodplain management. The framework in this study is illustrated using the observed and projected rainfall data in Cook County, Illinois, providing a road map to evaluate climate change impacts on urban flooding and a plan for adaptation. Numerous studies attempt to identify the implications of climate change with respect to hydrologic extremes (e.g., IPCC, 2007; CCSP, 2008; Milly et al., 2008). These studies project future climate conditions with more frequent extreme precipitation events in many regions around the world, including parts of the United States. In particular, it has been projected that northeastern Illinois, including the Chicago metropolitan area, will experience more frequent and more intense rainfall events in the future (Markus et al., 2012), which will lead to more intense and more frequent urban flooding events and to increased human, environmental, and economic risks. Thus, various planning and management measures need to be considered by urban communities which are responsible for administering ordinances governing the construction and maintenance of stormwater management systems, and for floodplain management to address public safety concerns, property damage, and economic interruption from intense precipitation. In these efforts, effective communication of climate change impacts on urban watersheds/sewer sheds is needed. Data should be delivered at the watershed level in a form that can be incorporated in watershed planning at the community level. Delivery of useful climate change information is critical for community planning and adaptation to changing climate conditions. It is common practice that future climate projections, which are based on global circulation models (GCM), are downscaled to finer temporal and spatial scales using statistical or dynamical downscaling models. However, watershed-scale climate data generated by climate models still do not provide precipitation data in a format useful for community engineers and planners to prepare, mitigate, and adapt to future conditions. Furthermore, city managers and decision makers need quantifiable future risk to demonstrate the need for adaptive actions, such as retrofitting storm sewers and other water conveyance structures or adopting higher regulatory design standards within the community. This is not offered by the present climate modeling outputs. In this research, a method is designed to analyze and express climate data in a format that can be readily used to assess future extreme precipitation events in models commonly used for sizing stormwater infrastructure and identifying flooding potential. In this method, future conditions climate data are analyzed to prepare precipitation maps for selected design storm frequencies which can be used to model future climate conditions of stormwater runoff and flood risk. This report presents a newly designed research framework to determine future conditions rainfall frequency maps, illustrating it in Cook County, Illinois, for the 24-hour duration rainfall event and for a range of recurrence intervals (also called return periods). Engineers commonly use these maps to determine the appropriate return period rainfall amount by interpolating between the isohyetals to evaluate options for storm and flood water management. Impacts of future climate conditions can then be convincingly demonstrated using conventional engineering to show changes in flooding frequency and extent, as well as damage comparisons associated with changing intense precipitation. Using standard and familiar models with future conditions precipitation scenarios facilitates communication of quantifiable future risk and supports community decision makers so they can plan, mitigate, and adapt to future conditions. This directly supports climate adaptation and mitigation by providing an understandable method for community engineers and planners to demonstrate the impact of climate change at the local level and develop specific adaptation strategies that will reduce future risk.published or submitted for publicationis peer reviewedOpe