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J C Sharp

Publications and source records attributed to J C Sharp.

At least 37 records · Page 2Linked to original sources
PubMed1993

Epidemiological aspects of outbreaks of food-borne salmonellosis in Scotland between 1980 and 1989.

Between 1980 and 1989, 2,212 outbreaks of food-borne infection were reported in Scotland. Of 2,073 episodes for which a causative agent was established, 1,732 (84%) were caused by salmonellae. An average of 980 people were affected each year, while the average number of individuals infected per general outbreak was 16.8. The infected foods were consumed outside Scotland in 25% of the outbreaks. In 75% of 1,107 episodes where the location was specified, the implicated foods were consumed in the home; hotels and restaurants accounted for 15%. Specific food items were identified in 603 (35%) of the 1,732 outbreaks; poultry meat was responsible for 332 (55%) and milk 49 (8%), while eggs accounted for 23 (4%) outbreaks.

Animals↗
PubMed1992

Rapid localization of concave volumes by conformal NMR spectroscopy.

"Conformal" spectroscopy is a method for the acquisition of accurately localized NMR spectra from noncuboidal regions with optimum signal-to-noise ratio, and is based upon the localization of volumes defined by a number of oblique intersecting selected slices. We have previously demonstrated conformal localization of volumes with convex surfaces. In this paper we extend the technique to the localization of concave volumes.

Humans↗
PubMed1991

Rugby injuries.

Explore the source record for details and available documents.

Football↗
PubMed1991

A quantitative analysis of the accuracy of in vivo pH measurements with 31P NMR spectroscopy: assessment of pH measurement methodology.

31P NMR spectroscopy provides a means of monitoring intracellular pH (pHi). In order to determine the significance of observed pH changes, an assessment of the measurement uncertainty is required. This paper considers the possible sources of error involved, firstly in chemical shift assignment and, secondly, in relating chemical shift to pH. A statistical analysis of these errors is presented and an expression for the accuracy of pH measurements obtained using in vivo 31P NMR spectroscopy is derived. Computer simulations and clinical measurements are considered to determine the likely error in clinical measurements. A comparison of pH measurement methodology using a centre-of-gravity calculation, Gaussian and Lorentzian fitting is also presented and discussed.

Humans↗
PubMed1990

Padé-Laplace method for the analysis of time-resolved fluorescence decay curves.

The interpretation of fluorescence intensity decay times in terms of protein structure and dynamics depends on the accuracy and sensitivity of the methods used for data analysis. The are many methods available for the analysis of fluorescence decay data, but justification for choosing any one of them is unclear. In this paper we generalize the recently proposed Padé-Laplace method to include deconvolution with respect to the instrument response function. In this form the method can be readily applied to the analysis of time-correlated single photon counting data. By extensive simulations we have shown that the Padé-Laplace method provides more accurate results than the standard least squares method with iterative reconvolution under the condition of closely spaced lifetimes. The application of the Padé-Laplace method to several experimental data sets yielded results consistent with those obtained by use of the least squares analysis.

Fluorescence↗
PubMed1990

Tryptophan-47 rotational isomerization in variant-3 scorpion neurotoxin. A combination thermodynamic perturbation and umbrella sampling study.

A combination thermodynamic perturbation and umbrella sampling study predicts two free energy wells for the rotational isomerization of the variant-3 scorpion neurotoxin tryptophan-47 indole side chain. One well has the indole side chain in the crystallographic orientation; the other has the indole rotated approximately 220 degrees to form a new conformation with a relative free energy of 3 +/- 2 kcal/mol. The activation barrier is 8.5 kcal/mol from the crystallographic well, from which transition state theory predicts a rate of escape of 2 x 10(5) s-1. Correlations in the displacements of side chains neighboring tryptophan-47 and the isomerization reaction coordinate last up to 20 ps. Favorable conditions of experimental verification are discussed.

Algorithms↗
PubMed1990

Comparison of 5-fluorouracil pharmacokinetics following intraperitoneal and intravenous administration using in vivo 19F magnetic resonance spectroscopy.

Intrahepatic pharmacokinetic studies of 5-Fluorouracil (5 FU) metabolism following intravenous and intraperitoneal administration have been undertaken in four patients using in vivo 19F nuclear magnetic resonance spectroscopy. Following intravenous administration, 5 FU decayed with "half times" ranging from 5 to 17 min. There was considerable variation of 5 FU pharmacokinetics between patients following intraperitoneal administration. Peritoneal contamination by infused 5 FU was considered to be a significant problem in one patient. A technique for providing superficial signal suppression was therefore investigated and its efficacy for excluding signal from the peritoneal space has been demonstrated. Owing to the potential for contamination from peritoneal 5 FU, the accumulation of fluoro-beta-alanine (FBAL) is a more reliable indicator of drug catabolism than the measurement of unlocalized "hepatic" 5 FU. Rapid intrahepatic catabolism of 5 FU to FBAL was demonstrated in all patients. However, there was greater pharmacokinetic variation following intraperitoneal administration than following intravenous administration. Therapeutic implications of intravenous compared with intraperitoneal administration of 5 FU are discussed.

Fluorouracil↗
PubMed1989

Conformal NMR spectroscopy: accurate localization to noncuboidal volumes with optimum SNR.

"Conformal Spectroscopy" is a general method for the acquisition of accurately localized NMR spectra from noncuboidal regions with optimum signal-to-noise ratio (SNR). The method is based upon the localization of volumes defined by a number of intersecting oblique slices and may be implemented using standard imager hardware. Conformal techniques can enhance many existing localization sequences such as ISIS (31P) and STEAM (1H) resulting in typical SNR improvements of around 1.8, equivalent to a more than threefold reduction in acquisition time. Applications include in vivo tumor spectroscopy.

Breast Neoplasms↗
PubMed1989

The use of an improved inversion pulse with the spin-echo/inversion-recovery sequence to give increased accuracy and reduced imaging time for T1 measurements.

The hyperbolic secant inversion pulse has been incorporated into the interleaved saturation-recovery/inversion-recovery sequence to provide T1 measurements combining high precision with a significantly reduced imaging time (a mean accuracy of 2% over a T1 range of 300 to 1650 ms for standard gel phantoms, with Tr1 = Tr2 = 2.0 s, Ti = 0.67 s).

Humans↗
PubMed1989

An outbreak of waterborne cryptosporidiosis caused by post-treatment contamination.

An outbreak of waterborne cryptosporidiosis affecting 27 persons, diagnosed stool positive, occurred in Ayrshire in April 1988. Twenty-one in 27 confirmed cases required some form of fluid replacement therapy. Local general practitioners indicated a two- to fivefold increase in diarrhoeal disease during the outbreak, and following enquiries made by Environmental Health Officers it became apparent that many hundreds of people had suffered a diarrhoeal illness at that time. Cryptosporidium spp. oocysts were detected in the treated chlorinated water supply system, in the absence of faecal bacterial indicators. Oocyst contamination of a break-pressure tank containing final water for distribution was the cause of this waterborne outbreak. An irregular seepage of oocyst-containing water, which increased during heavy rains, was the cause of the break-pressure tank contamination, rather than a failure of the water-treatment processes. The waterborne route should be considered when clusters of cryptosporidiosis-associated with potable water occur. Waterborne cryptosporidiosis can occur in the absence of other faecal indicators of contamination.

Adult↗
PubMed1988

Poultry-borne salmonellosis in Scotland.

Between 1980-5, 224 outbreaks of salmonellosis associated with poultry-meat were reported in Scotland. In total 2245 persons were affected, 12 of whom died. Twenty-one salmonella serotypes were identified from those affected, while 33 serotypes were isolated from poultry during routine monitoring and disease investigation. Existing measures to prevent the spread of salmonellae within poultry flocks and processing plants are failing. It is suggested that irradiation of poultry-meat may be the only effective method of reducing the public health problem of poultry-borne salmonellosis.

Animals↗