Spatial distribution of the active surveillance of sheep scrapie in Great Britain: an exploratory analysis

Background  

This paper explores the spatial distribution of sampling within the active surveillance of sheep scrapie in Great Britain. We investigated the geographic distribution of the birth holdings of sheep sampled for scrapie during 2002 – 2005, including samples taken in abattoir surveys (c. 83,100) and from sheep that died in the field ("fallen stock", c. 14,600). We mapped the birth holdings by county and calculated the sampling rate, defined as the proportion of the holdings in each county sampled by the surveys. The Moran index was used to estimate the global spatial autocorrelation across Great Britain. The contributions of each county to the global Moran index were analysed by a local indicator of spatial autocorrelation (LISA).     

Biophysical basis of brain activity: implications for neuroimaging

In vivo 13C magnetic resonance spectroscopy (MRS) studies of the brain have quantitatively assessed rates of glutamate-glutamine cycle (Veye) and glucose oxidation (CMRGle(ox)) by detecting 13C label turnover from glucose to glutamate and glutamine. Contrary to expectations from in vitro and ex vivo studies, the in vivo 13C-MRS results demonstrate that glutamate recycling is a major metabolic pathway, inseparable from its actions of neurotransmission. Furthermore, both in the awake human and in the anesthetized rat brain, Veye and CMRGle(ox) are stoichiometrically related, where more than two thirds of the energy from glucose oxidation supports events associated with glutamate neurotransmission. The high energy consumption of the brain measured at rest and its quantitative relation to neurotransmission reflects a sizeable activity level for the resting brain. The high activity of the non-stimulated brain, as measured by cerebral metabolic rate of oxygen use (CMRO2), establishes a new neurophysiological basis of cerebral function that leads to reinterpreting functional imaging data because the large baseline signal is commonly discarded in cognitive neuroscience paradigms. Changes in energy consumption (delta CMRO2%) can also be obtained from magnetic resonance imaging (MRI) experiments, using the blood oxygen level-dependent (BOLD) image contrast, provided that all the separate parameters contributing to the functional MRI (fMRI) signal are measured. The BOLD-derived delta CMRO2% when compared with alterations in neuronal spiking rate (delta v%) during sensory stimulation in the rat reveals a stoichiometric relationship, in good agreement with 13C-MRS results. Hence fMRI when calibrated so as to provide delta CMRO2% can provide high spatial resolution evaluation of neuronal activity. Our studies of quantitative measurements of changes in neuroenergetics and neurotransmission reveal that a stimulus does not provoke an arbitrary amount of activity in a localized region, rather a total level of activity is required where the increment is inversely related to the level of activity in the non-stimulated condition. These biophysical experiments have established relationships between energy consumption and neuronal activity that provide novel insights into the nature of brain function and the interpretation of fMRI data.     

Searching for responsible and sustainable recreational fisheries in the Anthropocene

Recreational fisheries that use rod and reel (i.e., angling) operate around the globe in diverse freshwater and marine habitats, targeting many different gamefish species and engaging at least 220 million participants. The motivations for fishing vary extensively; whether anglers engage in catch-and-release or are harvest-oriented, there is strong potential for recreational fisheries to be conducted in a manner that is both responsible and sustainable. There are many examples of recreational fisheries that are well-managed where anglers, the angling industry and managers engage in responsible behaviours that both contribute to long-term sustainability of fish populations and the sector. Yet, recreational fisheries do not operate in a vacuum; fish populations face threats and stressors including harvest from other sectors as well as environmental change, a defining characteristic of the Anthropocene. We argue that the future of recreational fisheries and indeed many wild fish populations and aquatic ecosystems depends on having responsible and sustainable (R&S) recreational fisheries whilst, where possible, addressing, or at least lobbying for increased awareness about the threats to recreational fisheries emanating from outside the sector (e.g., climate change). Here, we first consider how the concepts of R&S intersect in the recreational fishing sector in an increasingly complex socio-cultural context. Next, we explore the role of the angler, angling industry and decision-makers in achieving R&S fisheries. We extend this idea further by considering the consequences of a future without recreational fisheries (either because of failures related to R&S) and explore a pertinent case study situated in Uttarakahand, India. Unlike other fisheries sectors where the number of participants is relatively small, recreational angling participants are numerous and widespread, such that if their actions are responsible, they have the potential to be a key voice for conservation and serve as a major force for good in the Anthropocene. What remains to be seen is whether this will be achieved, or if failure will occur to the point that recreational fisheries face increasing pressure to cease, as a result of external environmental threats, the environmental effects of recreational fishing and emerging ethical concerns about the welfare of angled fish.     

Refilling of ocular lens capsule with copolymeric hydrogel containing reversible disulfide

Polymer solutions can fill any potential irregular cavity using minimally invasive techniques and thus have potential uses in ophthalmology. We prepared acrylamide hydrogels containing disulfide bonds by free radical polymerization in aqueous ethanol. The hydrogels were liquefied using dithiothreitol to yield water-soluble acrylamide copolymers containing pendant thiol (-SH) groups. The weight average molecular weights of the copolymers ranged from 1.43 x 10(5) to 9.22 x 10(5) daltons by GPC. Ellman's analysis and Raman spectroscopy confirmed the presence of -SH. The aqueous solutions of these purified thiol-containing copolymers were oxidized with 3,3'-dithiodipropionic acid or air to reform the hydrogels. The moduli of the reformed hydrogels ranged from 0.27 to 1.1 kPa depending on concentration and thiol content. Rapid endocapsular gelation yielded optically clear gel within the lens capsular bag. This technique now enables us to validate methods to determine the biomechanics of the lens and its role in accommodation.     

Immortalization of swine umbilical vein endothelial cells (SUVECs) with the simian virus 40 large-T antigen

Implementation of the swine umbilical vein endothelial cells (SUVECs) model in vitro can be instrumental in determining the biology of endothelial cells. We have generated an immortalized endothelial cell line, G-1410, using Simian virus 40 T-antigen (SV40 T-ag) primarily to overcome the short life span before the onset of senescence and high variability among enzymatically isolated cells of primary cultures. Fast proliferating cells were selected from cultures and, after a fifth passage, examined for the presence of the SV40 T-ag by PCR and immunocytochemistry. Phase contrast and transmission electron microscopy revealed that G-1410 cells did not differ morphologically from SUVECs. The G-1410 cells exhibited positive staining for vascular endothelial (VE)-cadherin and von Willebrand factor (vWF), and formed capillary-like tube structures on Matrigel. Despite the strong oncogenic signal provided by SV40 T-ag, these transformed G-1410 cells have remained karyotypically normal and non-tumorigenic. G-1410 cells also responded to stimulation with VEGF, FGF-2, and newborn calf serum. Moreover, G-1410 cells showed elevated expression of VEGF120, VEGF164 (VEGF-A), and FGF-2 at both mRNA and protein levels. In conclusion, based on the cytological and functional evaluation of the newly obtained immortalized cell line, it can be concluded that G-1410 cells provide a useful tool for studying the effects of VEGF and FGF systems, and other signal transduction pathways related to angiogenesis.     

Preparing for a changing future in recreational fisheries: 100 research questions for global consideration emerging from a horizon scan

Reviews in Fish Biology and Fisheries - Recreational fisheries hold immense ecological, social, and economic value. The management of these fisheries is increasingly important as we move forward in...     

Quality improvement report: The “jaundice hotline” for the rapid assessment of patients with jaundice

ProblemPatients with jaundice require rapid diagnosis and treatment, yet such patients are often subject to delay.DesignAn open referral, rapid access jaundice clinic was established by reorganisation of existing services and without the need for significant extra resources.

Background and setting

A large general hospital in a largely rural and geographically isolated area.

Key measures for improvement

Waiting times for referral, consultation, diagnosis, and treatment, length of stay in hospital, and general practitioners'' and patients'' satisfaction with the service.

Strategies for change

Referrals were made through a 24 hour telephone answering machine and fax line. Initial assessment of patients was carried out by junior staff as part of their working week. Dedicated ultrasonography appointments were made available.

Effects of change

Of 107 patients seen in the first year of the service, 62 had biliary obstruction. The mean time between referral and consultation was 2.5 days. Patients who went on to endoscopic retrograde cholangiopancreatography waited 5.7 days on average. The mean length of stay in hospital in the 69 patients who were admitted was 6.1 days, compared with 11.5 days in 1996, as shown by audit data. Nearly all the 36 general practices (95%) and the 30 consecutive patients (97%) that were surveyed rated the service as above average or excellent.

Lessons learnt

An open referral, rapid access service for patients with jaundice can shorten time to diagnosis and treatment and length of stay in hospital. These improvements can occur through the reorganisation of existing services and with minimal extra cost.     

Selective pharyngeal brain cooling]

Whole-body cooling can be used in the treatment of various brain pathologies, for example, after hypoxic events. Potential complications include haemodynamic instability, coagulation disorders and infection. Selective brain cooling (SBC) would therefore appear to make good sense. In an animal model a new approach to SBC was therefore evaluated. A rat weighing 350 g was sedated with alpha-chloralose (40 mg/kg/h) and d-tubocurarine (4.05 mg/kg/h), mechanically ventilated and placed on a heating pad. A thermocouple was introduced into the somatosensory cortex to a depth of 2.5 mm. SBC was achieved using a novel approach: PTFE tubing (ID 100 microns) with an inlet and an outlet was wrapped around and glued to a piece of wood, and introduced non traumatically into the pharynx. The tubing was perfused with cold water (+4 degrees C). Under SBC the cortical temperature dropped from 38.4 degrees C to 27.7 degrees C while the core temperature remained stable. In an animal model SBC was successfully accomplished via the pharynx. Further studies should now be done to evaluate the effectiveness of this approach in larger animals with potentially different anatomical features.