PubMed Health⌕ Search

Biomedical subjects

G Widdowson

Publications and source records attributed to G Widdowson.

7 recordsLinked to original sources
PubMed1982

A candidate reference method for uric acid in serum. II. Interlaboratory testing.

We describe the interlaboratory testing of a candidate Reference Method (Part I) for uric acid in serum. The method is based on the ultrasound spectrophotometric quantitation of uric acid before and after incubation with uricase. A comprehensive investigation involving 12 laboratories was organized to document the transferability, intra- and interlaboratory precision, and general reliability of the candidate Reference Method. The interlaboratory CV with this method was about 2 to 6% for uric acid concentrations ranging from 0.12 to 0.60 mmol/L. The results detailed here demonstrate that the method can be successfully duplicated among different laboratories.

Evaluation Studies as Topic↗
PubMed1979

An abnormality of cell behaviour in human dystrophic muscle cultures: a time-lapse study.

The initiation of monolayer mass cell cultures from adult human biopsies has revealed a striking abnormality in the growth and development pattern of muscle cultures from Duchenne-type dystrophy. This abnormality in cell behaviour was seen as early as 4 days in culture, well before myotube formation or confluence, and consisted of areas where cells clustered together in a multilayered mass rather than showing the typical monolayer distribution normally observed. To gain some insight into the mechanism of cell cluster development, we have examined such a culture by time-lapse cinematography and also the cell behaviour of other control cultures. The results of this study show that the clusters enlarged primarily by cell division and, to a lesser extent, by the acquisition of neighbouring cells. Furthermore, none of the single cells surrounding the clusters exhibited contact inhibition of movement. This behaviour was not observed in the other cultures examined. These findings could be indicative of an abnormality in the cell surface or cell-locomotory machinery of dystrophic cells.

Adolescent↗
PubMed1977

Plasma high-density lipoprotein cholesterol level. Influence of risk factor intervention.

Determinants of circulating high density lipoproteins (HDL) were sought in 301 men studied during a year of participation in a coronary prevention program. Mean plasma HDL-cholesterol concentration rose by 2.8 mg/dl (6%) in the group receiving multifactor intervention, but the change did not differ significantly from that in the comparison group. Larger changes in both directions were seen in many individuals. Multiple regression analysis of these changes indicates that increased plasma HDL levels occur when plasma triglyceride level is decreased, cigarette smoking is reduced, and habitual alcohol intake is increased. Increases in the concentration of HDL-cholesterol also tended to accompany adherence to the fat-controlled diet, reduction in LDL-cholesterol level, and loss of body weight. Conventional coronary prevention programs are unlikely to have an adverse influence on this new, risk-lowering factor.

Adult↗
PubMed1977

Expired air carbon monoxide and serum thiocyanate as objective measures of cigarette exposure.

Expired air carbon monoxide (CO) and serum thiocyanate (SCN) were used to asses exposure to cigarettes in 139 middle-aged men. Subjects who reported smoking cigarettes generally had CO levels exceeding 8ppm and SCN levels exceeding 100umol/L; non-smokers had lower levels. For both tests the mean concentration among men smoking more than one pack daily was three times that of non-smokers. The is a high correlation between the two tests (r=.571 for smokers), an association that was largely independent of the smaller correlations between either test and reported smoking frequency (r=.476 for CO; r=.479 for SCN). The ability to distinguish between individuals who reported "typical" smoking habits and non-smokers was best when the CO and SCN analyses were used together to take advantage of their separate sources of variance; it was 99 per cent when the two tests were mutually concordant (91 per cent of cases). The CO and SCN measurements allowed 16 individuals who reported light smoking habits to be categorized into high and low presumptive tobacco exposure groups. The two tests are inexpensive and suitable for use in epidemiologic and health care delivery programs.

Adult↗