Biomedical subjects

Claire Robertson

Publications and source records attributed to Claire Robertson.

4 recordsLinked to original sources

PubMed2005

Attainment of precision in implementation of 24 h dietary recalls: INTERMAP UK.

Collection of complete and accurate dietary intake data is necessary to investigate the association of nutrient intakes with disease outcomes. A standardised multiple-pass 24 h dietary recall method was used in the International Collaborative Study of Macro- and Micronutrients and Blood Pressure (INTERMAP) to obtain maximally objective data. Dietary interviewers were intensively trained and recalls taped, with consent, for randomly selected evaluations by the local site nutritionist (SN) and/or country nutritionists (CN) using a twelve-criterion checklist marked on a four-point scale (1, retrain, to 4, excellent). In the Belfast centre, seven dietary interviewers collected 932 24 h recalls from 40-59-year-old men and women. Total scores from the 134 evaluated recalls ranged from thirty-four to the maximum forty-eight points. All twelve aspects of the interviews were completed satisfactorily on average whether scored by the SN (n 53, range: probing 3.25 to privacy of interview 3.98) or CN (n 19, range: probing 3.26 to pace of interview and general manner of interviewer 3.95); the CN gave significantly lower scores than the SN for recalls evaluated by both nutritionists (n 31, Wilcoxon signed rank test, P=0.001). Five evaluations of three recalls identified areas requiring retraining or work to improve performance. Reporting accuracy was estimated using BMR; energy intake estimates less than 1.2 x BMR identifying under-reporting. Mean ratios in all age, sex and body-mass groups were above this cut-off point; overall, 26.1 % were below. Experiences from the INTERMAP Belfast centre indicate that difficulties in collection of dietary information can be anticipated and contained by the systematic use of methods to prevent, detect and correct errors.

Blood Pressure↗

PubMed2004

Properties of SEPT9 isoforms and the requirement for GTP binding.

Members of the evolutionarily conserved septin family of genes are emerging as key components of several cellular processes including membrane trafficking, cytokinesis, and cell-cycle control events. SEPT9 has been shown to have a complex genomic architecture, such that up to 15 different isoforms are possible by the shuffling of five alternate amino termini and three alternate carboxy termini. Genomic and transcriptional alterations of SEPT9 have been associated with neoplasia. The present study has used a Sept9-specific antibody to determine the pattern of isoform expression in a range of tumour cell lines. Western blot analysis indicated considerable variation in the relative amounts and isoform content of Sept9. Immunofluorescence studies showed a range of patterns of cytoplasmic localization ranging from mainly particulate to mainly filamentous. Expression constructs were also generated for each amino terminal isoform to investigate the patterns of localization of individual isoforms and the effects on cells of ectopic expression. The present study shows that the epsilon isoform appears filamentous in this overexpression system while the remaining isoforms are particulate and cytoplasmic. Transient transfection of individual constructs into tumour cell lines results in cell-cycle perturbation with a G2/M arrest and dramatic growth suppression, which was greatest in cell lines with the lowest amounts of endogenous Sept9. Similar phenotypic observations were made with GTP-binding mutants of all five N-terminal variants of Sept9. However, dramatic differences were observed in the kinetics of accumulation of wild-type versus mutant septin protein in transfected cells. In conclusion, the present study shows that the expression patterns of Sept9 protein are very varied in a panel of tumour cell lines and the functional studies are consistent with a model of septin function as a component of a molecular scaffold that contributes to diverse cellular functions. Alterations in the levels of Sept9 protein by overexpression of individual isoforms can clearly perturb cellular behaviour and may thus provide a mechanistic explanation for observations of deranged septin expression in neoplasia.

Actins↗

PubMed2004

Standardised coding of diet records: experiences from INTERMAP UK.

Coding diet records is a basic element of most dietary surveys, yet it often receives little attention even though errors in coding can lead to flawed study results. In the INTERnational study of MAcro- and micronutrients and blood Pressure (INTERMAP study), efforts were made to minimise errors in coding the 18, 720 diet records. Staff were centrally trained and certified before being able to process study data and ongoing quality control checks were performed. This involved the senior (site) nutritionist re-coding randomly selected diet records. To facilitate standardisation of coding in the UK, a code book was designed; it included information about coding brand items, density and portion size information, and default codes to be assigned when limited information was available for food items. It was found that trainees, despite previous experience in coding elsewhere, made coding errors that resulted in errors in estimates of daily energy and nutrient intakes. As training proceeded, the number of errors decreased. Compilation of the code book was labour-intensive, as information from food manufacturers and retailers had to be collected. Strategies are required to avoid repetition of this effort by other research groups. While the methods used in INTERMAP to reduce coding errors were time consuming, the experiences suggest that such errors are important and that they can be reduced.

Diet↗

PubMed2004

Tracing ingestion of 'novel' foods in UK diets for possible health surveillance--a feasibility study.

OBJECTIVE: To investigate the feasibility of using commercially available data on household food consumption to carry out food and nutritional surveillance. DESIGN: Taylor Nelson Sofres (TNS) collects information on foods brought home for consumption among a representative quota sample of the British population. In total, 33,177 households and 105,667 individuals provided data between 1991 and 2000. These were used to investigate sociodemographic, geographical and temporal trends in purchase patterns of the main macronutrients and four groups of marker products. RESULTS: Sociodemographic characteristics of the TNS sample were broadly consistent with those of the British population. Estimated energy intakes were slightly low (1667+/-715 kcal) in comparison with other national data. However, percentage energy contributions were consistent with national trends: e.g. consumption of alcohol in the home increased between 1991 and 2000 with higher intakes among more affluent households, while fat intakes decreased slightly over the same period. Significant temporal, geographic and socio-economic trends were found for all nutrients (P<0.0001). Intakes of marker products were sparse (purchased by <4% of households), but significant variations were detected in the proportion of households purchasing some or all of the marker products across temporal, geographic and socio-economic strata. CONCLUSIONS: A prospective nutrient surveillance system could be used to trace consumption patterns of foods or nutrients to inform nutritional surveillance. However, existing data sources would require a number of modifications to increase their suitability for such a project. Increasing surveillance to consider ingredients would require the development of a central coding system, with electronically linked barcode, ingredient and nutrient information.

Adolescent↗