Pacific rats or kiore (Rattus exulans) were commensal with Polynesians, and accompanied them to New Zealand in the 13th century or possibly earlier (Atkinson & Towns 2005). Apart from endemic bats no terrestrial mammals lived on the New Zealand archipelago at that stage. Pacific rats colonised both main islands and many others, and had a deleterious impact on native plant seeds, invertebrates, lizards and birds. With the introduction, by Europeans, of other rodent species and mustelids during the 18th century, the previously ubiquitous distribution of Pacific rats became severely restricted (Atkinson & Towns 2005). On mainland New Zealand, Pacific rats are now known only from seven sites in south-west South Island (Atkinson & Towns 2005). All other locations are on Stewart Island and small offshore islands. It has been suggested that the real distribution of Pacific rats may be more extensive, but disguised by misidentification or lack of trapping effort (Ruscoe 2004).

A large research effort worldwide is directed at reproducing 3D tissue and one recent development in the production of tissue engineering scaffolds is the use of biodegradable materials. This research investigates the possibility of producing biodegradable knitted scaffolds from poly lactic acid yarns. Degradation in the following biodegradable yarns is studied and the effect on their mechanical properties determined: a commercial polylactide (PLA) yarn Lactron (Kanebo Gohsen Ltd) and four yarns extruded in the Biomedical Textiles Research Centre (BTRC) from a medical grade Poly (L-lactide) (PLLA) polymer (purac biochem). To determine the degradation effects the mechanical properties were evaluated on a Nene tensile testing rig and samples observed under the scanning electron microscope; before and after the yarns were immersed in phosphate buffer solution (pH=7.4) for various lengths of time at 37°C. The yarns extruded in-house showed a gradual decline in tenacity over the degradation period, unlike the commercial yarn where the tenacity was maintained. This work shows that the degradation process is affected by factors such as extrusion speed and twist. With further knowledge, it may be possible to produce polylactic acid yarns with known degradation and cell attachment characteristics for textile tissue engineering scaffolds. In conclusion, polylactic acid yarns have good potential and biodegradable textile tissue engineering scaffolds look promising for the future.

An obesigenic environment is a potent force for promoting weight gain. However, not all people exposed to such an environment become obese; some remain lean. This means that some people are susceptible to weight gain (in a weight-promoting environment) and others are resistant. Identifying the characteristics of appetite control and food motivation in these two groups could throw light on the causes of weight gain and how this can be either treated or prevented. We have investigated the issue experimentally by identifying people who habitually consume a high-fat diet (greater than 43% fat energy). These individuals have been termed high-fat phenotypes. We have compared individuals, of the same age (mean=37 years old) and gender (male), who have gained weight (BMI=34) or who have remained lean (BMI=22). The susceptible individuals are characterised by a cluster of characteristics including a weak satiety response to fatty meals, a maintained preference for high-fat over low-energy foods in the post-ingestive satiety period, a strong hedonic attraction to palatable foods and to eating, and high scores on the TFEQ factors of Disinhibition and Hunger. The analysis of large databases suggests that this profile of factors contributes to an average daily positive energy balance from food of approximately 0.5 MJ. This profile of characteristics helps to define the symptomatology of a thrifty phenotype.

The emergence of tissue engineering has led to the development of three‐dimensional cellular scaffolds that reconstruct the tissue structure. Research into the use of biodegradable materials in scaffolds has grown; the aim is that when tissue growth is complete, the scaffold degrades completely. This research aims to design novel scaffolds and investigates biodegradable polylactide (PLA) yarns; in particular, poly(l‐lactide) (PLLA) yarns extruded in‐house. To study degradation and determine the effect on the biodegradable yarns/textiles, they were immersed in phosphate buffer solution (PBS, pH=7.4) for various durations at 37°C. Mechanical properties were evaluated on tensile testing rigs and they were observed, before and after the immersion period. Cells were then cultured (37°C, 5 per cent carbon dioxide in air) on the textiles for 1 week. As expected, after immersion, the yarns exhibit a decrease in elongation and tenacity. Initial results indicate that the yarn properties influence cell attachment and spreading.

There are two key methods in which fat intake may be manipulated; the ‘substitution model’ and the ‘reduction model’. However insufficient information is known about the mechanisms of dietary fat reduction in individuals who have successfully reduced their fat intake, to be clear as to which strategy offers the greatest chance of success. Our objective was to ascertain the most effective dietary intervention for improving cardiovascular risk profile. Eighty female volunteers (high fat consumers) were recruited. Each subject was randomly allocated into one of the following groups. Substitution of high-fat foods was made with reduced-fat products, by the reduction of high-fat foods, by a combination of substitution and reduction strategies, or no advice was given. Each intervention lasted 3 months. Anthropometric measures and fasting blood samples were taken at baseline and follow-up. The substitution intervention resulted in weight loss (mean −1.4 (95% CI −2.4, −0.2) kg) and reduced percentage body fat (mean −1.3 (95% CI −2.0, −0.5)%). There was no significant weight change with the other interventions. Fasting triacylglycerols (−0.2 (SEM 0.07) mM;P=0.04), cholesterol and C-reactive protein (CRP) levels (0.8 (SEM 0.2) mg/l;P=0.04) fell with the substitution intervention, but not with the other interventions. Insulin-like growth factor-1 increased with both substitution and reduction (P=0.02). There was no significant change in fasting insulin or glucose with any intervention. The substitution model of dietary intervention is effective even over a relatively short interval of time in reducing fasting total cholesterol, triacylglycerols and CRP. Although the group size for the present study was small and involved females only, it has significant implications for population intervention strategies.

Participants of the UK Women’s Cohort Study (n = 35,368) completed a 217-item Food Frequency Questionnaire. Low fat (LF) consumers (<68 g fat/day, <30%E from fat) had higher intakes of most nutrients per 1000 kcals compared to high-fat (HF) consumers (>93 g fat/day, >35%E from fat). More LF consumers followed low-fat diets (43%) compared to HF consumers (13%), ate small portion sizes, took nutritional supplements and abstained from alcohol. BMI and age were both higher in LF consumers. Fewer LF consumers lived with their partners compared to HF consumers. More LF consumers had no academic qualifications (20%) compared to HF consumers (14%), but more LF consumers had managerial occupations. A multiple logistic regression model was performed to determine independent predictors of low-fat consumption. The strongest predictors were vegetarian status, marital status, socio-economic group, employment status, education level and “following low-fat and slimming diets”. All differences described above were statistically significant (p < 0.01). These findings support the concept that LF consumers are more health conscious than HF consumers. Health promotion should therefore, be targeted towards non-vegetarian, married housewives who are in the lower socio-economic group for reduction of fat intake.

OBJECTIVE: To evaluate variations in children's attitudes to obesity in relation to age, gender and social class.DESIGN: Evaluation of sex, age and social class differences in judgements of figure drawings varying in body shape.SUBJECTS: 180 children aged from 4-11 from six schools, varying in the social background of their pupils.MEASUREMENTS: Self ratings of body shape, choices of ideal body shape now and in adulthood from a range of line drawings of figures varying in fatness, and behavioural and personality stereotype judgements of illustrations of thin, average and fat children.RESULTS: Few children in this age group were fat and few felt too fat; though a substantial minority felt too thin, Girls selected thinner ideal figures than boys, Children demonstrated strongly negative attitudes to obesity, which were less favourable among those who were older and from the higher social status schools.CONCLUSION: There are significant social variations in attitudes to obesity which might be important in understanding variations in the prevalence of obesity and weight control practices.