Socioeconomic position, growth and physical activity: associations with adult fat and lean mass in the MRC National Survey of Health and Development

Fat and lean mass have important implications for adult health and physical functioning, but few studies have examined their determinants. This thesis used a life course perspective to examine how explanatory factors across life relate to adult measures of fat and lean mass. The MRC National Survey of Health and Development was used—a British birth cohort study originally comprised of 5362 babies born in March 1946. At 60–64 years, 746 males and 812 females had fat and lean mass measures taken using dual energy X-ray absorptiometry. Linear regression was used to examine associations between prospectively ascertained explanatory variables (socioeconomic position, measures of growth, and physical activity) with these masses. Lower childhood and adult socioeconomic position, greater weight gains in childhood and adolescence (7-20 years), and lower current physical activity levels (measured objectively and by self-report) were all associated with higher fat mass, with evidence in females of cumulative benefits of leisure time physical activity across adulthood (36 to 60–64 years) in leading to lower fat mass. Higher childhood (females only) and adult (both sexes) socioeconomic position, higher birth weight, greater weight gain from birth to 20 years, and physical activity participation across adulthood were all associated with higher lean mass; associations with socioeconomic position and physical activity were found after adjustment for fat mass. Associations between lower childhood socioeconomic position and higher fat mass were partly mediated by weight gain from 7–20 years; associations with higher fat and lower lean mass were partly mediated by leisure time physical activity measures. Factors operating in both early and adult life were associated with adult fat and lean mass. These factors could be potential targets for public health strategies which seek to reduce fat mass and increase lean mass in the population

'Skeletal muscle function deficit' in a nationally representative British birth cohort in early old age

BACKGROUND: Recommendations for identifying age-related muscle dysfunction have recently been published. We aimed to compare definitions for clinically relevant weakness and low lean mass proposed by the Foundation for the National Institutes of Health (FNIH) Sarcopenia project with the definition of sarcopenia proposed by the European Working Group on Sarcopenia in Older People (EWGSOP). METHODS: 1566 men and women from a British birth cohort had measures of appendicular lean mass, grip strength and timed up and go speed at ages 60–64. Prevalence of low lean mass, weakness and slowness, identified using the FNIH and EWGSOP recommendations were estimated and compared: using kappa statistics and; by testing cross-sectional associations of both definitions of low lean mass and weakness with slowness and self-reported difficulties walking. RESULTS: The combined prevalence of low lean mass and weakness ranged from 1.1% in men using FNIH criteria to 6.4% in women using EWGSOP criteria. There was limited overlap between the groups identified using the different criteria, driven by limited agreement between the two definitions of low lean mass. Using FNIH criteria, both low lean mass and weakness were associated with higher odds of slowness and difficulties walking whereas low lean mass classified using EWGSOP criteria was not associated with these markers of mobility impairment. CONCLUSIONS: At relatively young ages, signs of skeletal muscle function deficit with potential clinical relevance are already identifiable in the general population. This suggests that implementation of strategies to prevent mobility limitations, related to age-related muscle dysfunction, may need to start at least as early as midlife

Collagen-Like Proteins in Pathogenic E. coli Strains

The genome sequences of enterohaemorrhagic E. coli O157:H7 strains show multiple open-reading frames with collagen-like sequences that are absent from the common laboratory strain K-12. These putative collagens are included in prophages embedded in O157:H7 genomes. These prophages carry numerous genes related to strain virulence and have been shown to be inducible and capable of disseminating virulence factors by horizontal gene transfer. We have cloned two collagen-like proteins from E. coli O157:H7 into a laboratory strain and analysed the structure and conformation of the recombinant proteins and several of their constituting domains by a variety of spectroscopic, biophysical, and electron microscopy techniques. We show that these molecules exhibit many of the characteristics of vertebrate collagens, including trimer formation and the presence of a collagen triple helical domain. They also contain a C-terminal trimerization domain, and a trimeric α-helical coiled-coil domain with an unusual amino acid sequence almost completely lacking leucine, valine or isoleucine residues. Intriguingly, these molecules show high thermal stability, with the collagen domain being more stable than those of vertebrate fibrillar collagens, which are much longer and post-translationally modified. Under the electron microscope, collagen-like proteins from E. coli O157:H7 show a dumbbell shape, with two globular domains joined by a hinged stalk. This morphology is consistent with their likely role as trimeric phage side-tail proteins that participate in the attachment of phage particles to E. coli target cells, either directly or through assembly with other phage tail proteins. Thus, collagen-like proteins in enterohaemorrhagic E. coli genomes may have a direct role in the dissemination of virulence-related genes through infection of harmless strains by induced bacteriophages

How patients understand depression associated with chronic physical disease - A systematic review

Background: Clinicians are encouraged to screen people with chronic physical illness for depression. Screening alone may not improve outcomes, especially if the process is incompatible with patient beliefs. The aim of this research is to understand peoples beliefs about depression, particularly in the presence of chronic physical disease. Methods: A mixed method systematic review involving a thematic analysis of qualitative studies and quantitative studies of beliefs held by people with current depressive symptoms. MEDLINE, EMBASE, PSYCHINFO, CINAHL, BIOSIS, Web of Science, The Cochrane Library, UKCRN portfolio, National Research Register Archive, Clinicaltrials.gov and OpenSIGLE were searched from database inception to 31st December 2010. A narrative synthesis of qualitative and quantitative data, based initially upon illness representations and extended to include other themes not compatible with that framework. Results: A range of clinically relevant beliefs was identified from 65 studies including the difficulty in labeling depression, complex causal factors instead of the biological model, the roles of different treatments and negative views about the consequences of depression. We found other important themes less related to ideas about illness: the existence of a self-sustaining depression spiral; depression as an existential state; the ambiguous status of suicidal thinking; and the role of stigma and blame in depression. Conclusions: Approaches to detection of depression in physical illness need to be receptive to the range of beliefs held by patients. Patient beliefs have implications for engagement with depression screening

Childhood socioeconomic position and adult leisure-time physical activity: A systematic review

Regular leisure-time physical activity (LTPA) benefits health and is thought to be less prevalent in lower socioeconomic groups. Evidence suggests that childhood socioeconomic circumstances can impact on adult health and behaviour however, it is unclear if this includes an influence on adult LTPA. This review tested the hypothesis that a lower childhood socioeconomic position (SEP) is associated with less frequent LTPA during adulthood. Studies were located through a systematic search of MEDLINE, Embase, PsycINFO, CINAHL and SPORTDiscus and by searching reference lists. Eligible studies were English-language publications testing the association between any indicator of childhood SEP and an LTPA outcome measured during adulthood. Forty-five papers from 36 studies, most of which were European, were included. In most samples, childhood SEP and LTPA were self-reported in midlife. Twenty-two studies found evidence to support the review’s hypothesis and thirteen studies found no association. Accounting for own adult SEP partly attenuated associations. There was more evidence of an association in British compared with Scandinavian cohorts and in women compared with men. Results did not vary by childhood SEP indicator or age at assessment of LTPA. This review found evidence of an association between less advantaged childhood SEP and less frequent LTPA during adulthood. Understanding how associations vary by gender and place could provide insights into underlying pathways

Entre a poeira e o silêncio: sobre exposições e construções da memória no Museu do Ceará (1932-1997)

This article discusses some manners to construct the meanings of the past into Museu do Ceará's exhibitions between 1932 and 1997. Based on issues of Social History of Memory, the meanings of dust and silence are highlighted in a way that the past is configured in the space of the exhibitions. The artifacts are treated taking into account underlying values and expectations that guide, in certain circumstances, connections and separations between past and present