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Biomedical subjects

T A Gough

Publications and source records attributed to T A Gough.

At least 19 recordsLinked to original sources
PubMed1992

Some features of Cannabis plants grown in the United Kingdom from seeds of known origin.

The cannabinoid content of UK-grown plants (up to the 6th generation) from Moroccan, Sri Lankan and Zambian seedstock was determined by TLC, GLC and HPLC. All plants from the 5th and 6th series resembled their parents, and UK-grown plants were always much greener than those grown overseas. Cannabinoid content remained broadly typical of the source countries. However, tetrahydrocannabinolic acid (THCA) consistently predominated over tetrahydrocannabinol (THC) to a far greater extent than in the original plants; the THCA/THC ratio was 17 in UK-grown plants compared with 2.0 in the plants from the original areas. Two types of plant emerged from the Moroccan seedstock, one tending to increased cannabidiol (CBD), the other tending to zero levels of this component. The first generation Sri Lankan plants revealed one type of plant with an increased CBD/THC ratio (1.7 compared with 0.11) but this returned to the original value in the succeeding generations. Other Sri Lankan plants had low or undetectable levels of CBD. Moroccan and Sri Lankan CBD-rich plants did not contain cannabichromene, although this cannabinoid was found in THC-rich plants. Zambian plants did not appear to show such a pattern. Zambian seedstock plants had total tetrahydrocannabivarin (diol and acid) levels greater than THC but the ratio was progressively reversed in succeeding generations. The study concludes that the ratios of particular cannabinoids is greatly influenced by the environment.

Cannabinoids↗
PubMed1979

The rapid determination of cocaine and other local anesthetics using field tests and chromatography.

The application of field tests and chromatography to the detection of cocaine and some other local anesthetics that have been used to adulterate cocaine is described. Initial screening of samples by field tests, followed by concurrent TLC and GC, enables rapid identification of these compounds to be achieved. In particular, the use of flow-programmed GC shortens the time for analysis compared with conventional GC and requires negligible equilibration time between consecutive runs [12]. The method gives reliable quantitative data.

Anesthetics, Local↗
PubMed1978

Analysis for volatile nitrosamines in salt-preserved foodstuffs traditionally consumed by southern Chinese.

Six types of salted fish and 10 other sorts of salted food products traditionally consumed by southern Chinese were analysed by GC-MS for the presence of volatile nitrosamines. The detection limit in the original raw food was 1 microg/kg for each nitrosamine. Only NDMA, in the range of 1-35 microg/kg, could be detected, in four of the six types of salted fish samples examined; and no nitrosamines were found in the other salted food products.

Animals↗
PubMed1978

Diffusion of nitrosamines through protective gloves.

A simple experimental demonstration of the permeability of protective gloves to volatile nitrosamines has been carried out. Rubber and polyvinyl chloride (PVC) gloves were turned inside out and the fingers filled with dilute solutions of nitrosamines in hexane. The outer faces of the fingers were washed with water at various times and the nitrosamine content of these washings determined. From these measurements the proportions of the various nitrosamines passing through the gloves were calculated. For both types of gloves N-nitrosopyrrolidine (NPYR) permeated the fingers most rapidly and to the greatest extent. Only a relatively small amount of N-nitrosodibutylamine (NDBA) was transmitted. It was also established that the rubber gloves themselves did not contain any of the common volatile nitrosamines; N-nitrosomethylphenylamine and N-nitrosodiphenylamine were also absent.

Chromatography, Gas↗
PubMed1977

Simple chemiluminescent detector for the screening of foodstuffs for the presence of volatile nitrosamines.

The construction and subsequent evaluation of an apparatus for the detection of trace amounts of nitrosamines is described. The apparatus consists of a gas chromatograph, a catalytic chamber to generate nitric oxide from eluted nitrosamines, and a chemiluminescent detector to measure the infra-red emission resulting from interaction of this gas with ozone. Examples of the use of the system for determining the nitrosamine concentration in food extracts and other materials are given.

Chromatography, Gas↗
PubMed1977

A search for volatile nitrosamines in East African spirit.

Spirits from areas of high and low incidence of cancer of the oesophagus were examined for volatile nitrosamines using a chemiluminescent detector. No nitrosamines were found, the detection limit being 0.001 microng/ml.

Africa, Eastern↗