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T England

Publications and source records attributed to T England.

9 recordsLinked to original sources

A quantitative risk assessment for the importation of brucellosis-infected breeding cattle into Great Britain from selected European countries.

Great Britain (GB) has been "Officially Brucellosis Free" (OBF) since 1991; because this disease has both public-health and international-trade implications, it is in the country's interest to maintain this freedom. A quantitative risk-assessment model was developed to determine the annual risk of importing brucellosis-infected breeding cattle into GB from Northern Ireland and the Republic of Ireland. (These countries exported the largest number of cattle into GB and were not brucellosis free during the development of the assessment in 2000.) We predicted that we can expect to import brucellosis from Northern Ireland every 2.63 years (1.89, 4.17) and from the Republic of Ireland, every 3.23 years (2.13, 5.88). The estimates of risk are sensitive to the assumed proportion of animals missed during routine surveillance that originate from OBF herds and the uncertainty associated with the surveillance test sensitivities. As a result of the assessment, the Department for Environment, Food and Rural Affairs (Defra) introduced post-calving testing for all cattle imported into British herds.

Animals↗

A simulation model of brucellosis spread in British cattle under several testing regimes.

Brucellosis is a widespread, economically devastating and highly infectious zoonosis. In cattle, infection predominantly is caused by Brucella abortus, and is usually detected in pregnant females through abortions. Great Britain (GB) has been declared free from brucellosis (officially brucellosis free (OBF)) since 1993 and as such is required by European Union (EU) regulations to test > or =20% of both beef and dairy cattle >24 months old routinely. Currently, however, GB serologically tests more cattle than required and the issue of reducing the level of testing has come under consideration. We developed a simulation model to determine the rate of spread of brucellosis under a variety of testing regimes. For dairy herds, we found that reducing the level of testing would have a major effect on the rate of spread of infection, should it be imported. For beef herds, reducing the level of testing would have much less effect. We also found that abortion notification is a very-important additional means of surveillance. As a result of our predictions, policy-makers decided not to reduce the level of testing and actively to promote abortion notification.

Abortion, Veterinary↗

Quantitative estimates of the risk of new outbreaks of foot-and-mouth disease as a result of burning pyres.

The risk of dispersing foot-and-mouth disease virus into the atmosphere, and spreading it to susceptible holdings as a result of burning large numbers of carcases together on open pyres, has been estimated for six selected pyres burned during the 2001 outbreak in the UK. The probability of an animal or holding becoming infected was dependent on the estimated level of exposure to the virus predicted from the concentrations of virus calculated by the Met Office, Bracknell. In general, the probability of infection per animal and per holding decreased as their distance from the pyre increased. In the case of two of the pyres, a holding under the pyre plumes became infected on a date consistent with when the pyre was lit. However, by calculating their estimated probability of infection from the pyres it was concluded that it was unlikely that in either case the pyre was the source of infection.

Animals↗

The steady-state levels of oxidative DNA damage and of lipid peroxidation (F2-isoprostanes) are not correlated in healthy human subjects.

Oxidative damage to DNA in human tissues can be determined by measuring multiple products of oxidative damage to the purine and pyrimidine bases using gas chromatography-mass spectrometry (GC-MS). Oxidative damage to lipids (lipid peroxidation) can be quantitated by the mass spectrometry-based determination of F2-isoprostanes, specific end-products of the peroxidation of arachidonic acid residues in lipids. For both DNA base damage products and 8-epi prostaglandin F2alpha (PGF2alpha), there is a wide variation in levels between different healthy human subjects. We measured multiple products of oxidative damage to DNA bases in white cells, and 8-epi PGF2alpha in plasma, from blood samples obtained from healthy human subjects in the UK and in Portugal. No correlation of 8-epi PGF2alpha levels with levels of any modified DNA base (including 8-hydroxyguanine) was observed. We conclude that no single parameter can be measured as an index of "oxidative stress" or "oxidative damage" in vivo.

Adult↗

Analytic solutions to compartmental models of the HIV/AIDS epidemic.

For many years compartmental models have provided useful insights into the spread of epidemics. Such models are usually fairly easy to set up, but even the simpler models have the disadvantage that they are intractable to analytic solution. In this paper we examine models of the HIV/AIDS epidemic, and show that the equations may be linearized in a piecewise manner over time, thus allowing analytic solutions to be obtained. Indications of the usefulness of this approach are provided. In particular, an analytic solution gives insight into the mechanism of the epidemic, together with a clearer picture of the sensitivity of results to changes in parameter values. Further, the processes of parameter estimation and the methodology of back-calculation also benefit from the provision of functional forms for the state variables.

Acquired Immunodeficiency Syndrome↗

Carbon fibre micro-electrodes for concomitant in vivo electrophysiological and voltammetric measurements: no reciprocal influences.

Differential pulse voltammetry and more recently cyclic voltammetry have been successfully used to monitor basal levels of endogenous chemicals by means of treated carbon fibre microbiosensors inserted in specific brain regions. In this study, feasibility of concomitant in vivo recordings of stable electrophysiological signals and basal ascorbate, catecholaminergic and indolaminergic voltammetric peaks at the same cerebral site by means of a single electrically treated carbon fibre micro electrode (microbiosensor) is presented. The results indicate that these two independent techniques can be combined in vivo at a single electrode, and that voltammetric measurements of unstimulated levels of extracellular compounds do not alter concomitant basal cell firing for a period long enough (more than 6 h) to allow pharmacological manipulations.

3,4-Dihydroxyphenylacetic Acid↗

Spontaneous preference for ethanol in naive rats is influenced by cholecystokinin A receptor antagonism.

Naive adult male Wistar rats free to choose between water or 10% ethanol (v/v) spontaneously became water-preferring (WP) rats, as they drank mainly water (approximately 35 ml per day), or alcohol-drinking (ED) rats, as they also drank a significant amount of ethanol (approximately 14 ml per day). The selective CCKA receptor antagonist L-364,718 at doses selective for the CCKA receptor (5 micrograms/kg, IP) halved the consumption of alcohol of the ED rats without modifying their total liquid in-take. In contrast, the CCKB antagonists L-365,260 or GV150013 were without effect when used at doses selective for the CCKB receptor. These data indicate that the CCK system could be involved in the modulation of alcohol intake. In particular, they suggest that CCKA receptors could play a role in the ethanol preference.

Alcohol Drinking↗