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J Robertson

Publications and source records attributed to J Robertson.

At least 37 records · Page 2Linked to original sources
PubMed2002

Body image and weight change in middle age: a qualitative study.

AIMS: To explore men's and women's experiences of weight change in adulthood, body image preferences and beliefs about the health consequences of overweight and to inform the development of a primary care intervention to prevent obesity. SAMPLE: Seventy-two men and women aged 35-55, with a range of BMIs from 22 to 29.9, were identified from two UK general practice registers and invited to participate in an interview about experiences of weight change in adulthood. METHODS: Audio tape recorded, semi-structured interviews were conducted in respondents' homes by trained researchers. Open-ended questions were used to collect experiences of weight change since early adulthood and views about weight change in middle age. Illustrations of a range of men's and women's body shapes were used to prompt discussion of respondents' preferences for male and female body shapes and their perspectives of the health, social and practical problems associated with underweight and overweight. The data were analysed using both quantitative and qualitative methods. RESULTS: Some 87% (33/38) of the women and 59% (20/34) of the men said that they had ever tried to lose weight. At least one instance of successful weight loss was reported by 58% of the women and 47% of the men, although many of these attempts were relatively short-lived and often motivated by specific goals such as a holiday or a wedding. Respondents were sceptical of the possibility of controlling weight without considerable personal sacrifice. Explanations for middle-age weight gain included a sedentary lifestyle, as well as several gender-specific reasons, including hormonal changes and comfort eating for women and beer drinking for men. Nearly all (97%) respondents associated heart disease with overweight, while diabetes was mentioned by only 22% and none mentioned cancer. CONCLUSION: People who have gained weight in middle age may be deterred from trying to prevent further gain by pessimism about the effort required. The efficacy of interventions to encourage relatively small substitutions and changes to diet and physical activity need to be tested. Interventions to help prevent weight gain in middle age could include information about the less widely known health risks such as diabetes and cancer.

Adult↗
PubMed2002

Costs of village community, residential campus and dispersed housing provision for people with intellectual disability.

BACKGROUND: In recent years, a growing volume of research evidence has been generated about the relative cost-effectiveness of various types of community-based residential supports for people with intellectual disability (ID) in the UK. However, few reliable data are available to inform planners, commissioners or service providers about the quality and costs of providing support within residential or village communities. METHODS: The evaluation described in the present paper aimed to fill some of the gaps in knowledge by examining the comparative costs of supporting people in village community settings, in National Health Service (NHS) residential campuses and in dispersed, community-based housing schemes. The complete service package received by each study participant was described and costed, and a series of statistical analyses was undertaken to identify factors associated with variations in the cost of support. The analyses reported in the present paper were based on comparisons of 86 people living in village communities, 133 in residential campuses and 281 in dispersed housing schemes. RESULTS: Wide variations in cost were found, not only between models of accommodation, but between individual organizations, settings and service users. Multivariate analysis revealed that higher costs were associated with supports for people with higher levels of ID and more severe challenging behaviour. The cost of support was affected by the size of the residential setting, with smaller facilities likely to be more expensive. Associations were also found between increased costs, and services for younger users, male users and people who had not moved from a NHS hospital. Generally, more sophisticated service processes within the setting were associated with higher costs; although systematic arrangements for supervision and training of staff had a negative effect on cost. CONCLUSIONS: The cost findings should be considered alongside evidence on outcomes. A comparison of village communities and dispersed housing schemes suggests that both models of provision appear be associated with particular benefits, although different types of setting are appropriate for different individuals and therefore, the continued development of a range of residential models is important.

Adult↗
PubMed2002

Sedation effects on responsiveness: evaluating the reduction of antipsychotic medication in people with intellectual disability using a conditional probability approach.

BACKGROUND: The impact of the withdrawal of long-term antipsychotic medication prescribed to adults with intellectual disabilities on behavioural functioning has been investigated using a real-time direct observation methodology. Previous authors have reported a significant post-reduction difference in engagement in activity between the successful drug reduction and control groups. METHOD: In the present study, sequential analysis of the relationship between staff:resident interaction and behavioural engagement was used to give a more precise measure of the extent to which user responsiveness is affected by drug withdrawal. Responsiveness was measured by calculating the likelihood of engagement occurring given the occurrence of staff interaction. This likelihood was represented by the statistic Yule's Q-value. RESULTS: High Yule's Q-value results pre- and post-baseline were found, indicating that clients were highly responsive to staff interaction. However, Yule's Q-value did not significantly increase following drug withdrawal. CONCLUSION: The present study provides no evidence of greater responsiveness following the withdrawal of psychotropic medication.

Adult↗
PubMed2002

Non-lethal viral challenge of influenza haemagglutinin and nucleoprotein DNA vaccinated mice results in reduced viral replication.

Influenza DNA vaccines have been widely studied in experimental animal models and protection documented after lethal viral challenge. In this study, we have investigated the humoral response after a non-lethal viral challenge of mice vaccinated with plasmids encoding the influenza haemagglutinin (HA) or nucleoprotein (NP) genes. BALB/c mice were immunized intramuscularly with three doses (100 microg) of HA, NP or backbone plasmid at 3-week intervals, or alternatively infected intranasally, before being challenged with homologous virus 13 weeks later. Mice were then sacrificed at weekly intervals and the antibody-secreting cell response was examined systemically (spleen and bone marrow) and in the respiratory tract (nasal associated lymphoid tissue (NALT) and lungs). Sera were collected after each dose of vaccine and at sacrifice and analyzed by ELISA, haemagglutination inhibition and virus neutralization assays. We found that previous viral infection apparently elicits sterilizing immunity. Vaccination with HA or NP DNA significantly reduced viral replication in the nasal cavity after viral challenge, however, increases in serum antibody titres were observed after challenge. Prior to challenge, specific antibody-secreting cells were observed in the systemic compartment after HA or NP DNA vaccination but were also found in the NALT after viral challenge. In conclusion, intramuscular DNA vaccination resulted in immunological memory in the systemic compartment, which was rapidly reactivated upon viral challenge.

Animals↗
PubMed2002

Social class gradients in health during adolescence.

STUDY OBJECTIVE: To review existing data on social class gradients in adolescent health and to examine whether such gradients exist in new data concerning US adolescents. DESIGN: Review of relevant publications and unpublished data; regression analyses using adolescent self reported health status data to determine whether there are gradients by social class, using three classes categorised by adolescent reported parental work status and education. PARTICIPANTS: Adolescents of ages 11-17. MAIN RESULTS: Findings from the literature indicate the presence of social class gradients in some but not all aspects of adolescent health. Results from new data showed social class gradients in several domains of health and in profiles of health. The likelihood of being satisfied with one's health, of being more resilient (better family involvement, better problem solving, more physical activity, better home safety), having higher school achievement, and of being in the best health profiles were significantly and progressively greater as social class rose. Moreover, the probability of being in the poorest health profile type group was progressively higher as social class declined. CONCLUSIONS: The review of existing data and the new findings support the existence of social class gradients in satisfaction with one's health, in resilience to health threats, in school achievement, and in being in the best health overall (as manifested by the health profiles composed of four major domains of health). The study had two especially notable findings: (1) the paucity of studies using the same or similar indicators, and (2) the consistent existence of social class gradients in characteristics related to subsequent health, particularly intake of nutritional foods and physical activity. The sparseness of existing data and the different aspects of health investigated in the relatively few studies underscore the need for (1) the development of conceptual models specifically focused on adolescent health and social class; (2) additional inquiry into the measurement of social class and adolescent perceptions of class; (3) inclusion of contextual variables in study design; and (4) longitudinal cohort studies to better understand the specific determinants of health during adolescence.

Adolescent↗
PubMed2001

The receptor tyrosine kinase EphB2 regulates NMDA-dependent synaptic function.

Members of the Eph family of receptor tyrosine kinases control many aspects of cellular interactions during development, including axon guidance. Here, we demonstrate that EphB2 also regulates postnatal synaptic function in the mammalian CNS. Mice lacking the EphB2 intracellular kinase domain showed wild-type levels of LTP, whereas mice lacking the entire EphB2 receptor had reduced LTP at hippocampal CA1 and dentate gyrus synapses. Synaptic NMDA-mediated current was reduced in dentate granule neurons in EphB2 null mice, as was synaptically localized NR1 as revealed by immunogold localization. Finally, we show that EphB2 is upregulated in hippocampal pyramidal neurons in vitro and in vivo by stimuli known to induce changes in synaptic structure. Together, these data demonstrate that EphB2 plays an important role in regulating synaptic function.

Animals↗
PubMed2001

A textile fibre survey as an aid to the interpretation of fibre evidence in the Sydney region.

Frequency figures of the fibre population on textile cinema seats were measured in Sydney, Australia, in winter. Sixteen seats were analysed from a very popular cinema complex, with 3025 fibres classified according to colour, generic class and fluorescence properties (100 grey-black cotton fibres only). The recovered fibres were mostly natural fibres (84%) with cotton the most common generic type (70%). On the contrary, man made fibres were relatively rare (15%) with rayon constituting the majority of these (51%). The most common colour/generic class combinations were grey-black cotton (33%) and blue cotton (30%) accounting for 63% of the total population. All other frequencies were below 5%, most below 1% using only the two properties of colour and generic class. Fluorescence properties were found to be very discriminating as far as grey-black cotton fibres were concerned. These features are considered and discussed and in particular, to emphasise the significance of fibres as evidence of contact.

Australia↗
PubMed2001

Mutational analysis of early region 4 of bovine adenovirus type 3.

The primary objective of characterizing bovine adenovirus type 3 (BAV3) in greater detail is to develop it as a vector for gene therapy and vaccination of humans and animals. A series of BAV3 early region 4 (E4) deletion-mutant viruses, containing deletions in individual E4 open reading frames (Orf) or combinations of Orfs, were generated by transfecting primary fetal bovine retinal cells with E4-modified genomic DNA. Each of these mutants was further analyzed for growth kinetics, viral DNA accumulation, and early-late protein synthesis. Mutant viruses carrying deletions in Orf1, Orf2, Orf3, or Orf4 showed growth characteristics similar to those of the E3-deleted BAV3 (BAV302). DNA accumulation and early/late protein synthesis were also indistinguishable from those of BAV302. However, mutant viruses carrying a deletion in Orf5, Orfs 1-3 (BAV429), or Orfs 3-5 (BAV430) were modestly compromised in their ability to grow in bovine cells and express early/late proteins. E4 mutants containing larger deletions, Orfs 1-3 (BAV429) and Orfs 3-5 (BAV430), were further tested in a cotton rat model. Both mutants replicated as efficiently as BAV3 or BAV302 in the lungs of cotton rats. BAV3-specific IgA and IgG responses were detected in serum and at the mucosal surfaces in cotton rats inoculated with mutant viruses. In vitro and in vivo characterization of these E4 mutants suggests that none of the individual E4 Orfs are essential for viral replication. Moreover, successful deletion of a 1.5-kb fragment in the BAV3 E4 region increased the available insertion capacity of replication-competent BAV3 vector (E3-E4 deleted) to approximately 4.5 kb and that of replication-defective BAV3 vector (E1a-E3-E4 deleted) to approximately 5.0 kb. This is extremely useful for the construction of BAV3 vectors that express multiple genes and/or regulatory elements for gene therapy and vaccination.

Adenoviridae Infections↗
PubMed2001

Apoptotic death of neurons exhibiting peripherin aggregates is mediated by the proinflammatory cytokine tumor necrosis factor-alpha.

Peripherin, a neuronal intermediate filament protein associated with axonal spheroids in amyotrophic lateral sclerosis (ALS), induces the selective degeneration of motor neurons when overexpressed in transgenic mice. To further clarify the selectivity and mechanism of peripherin-induced neuronal death, we analyzed the effects of peripherin overexpression in primary neuronal cultures. Peripherin overexpression led to the formation of cytoplasmic protein aggregates and caused the death not only of motor neurons, but also of dorsal root ganglion (DRG) neurons that were cultured from dissociated spinal cords of peripherin transgenic embryos. Apoptosis of DRG neurons containing peripherin aggregates was dependent on the proinflammatory central nervous system environment of spinal cultures, rich in activated microglia, and required TNF-alpha. This synergistic proapoptotic effect may contribute to neuronal selectivity in ALS.

Amyotrophic Lateral Sclerosis↗
PubMed2001

The impact of specialists on prescribing by general practitioners.

OBJECTIVE: To investigate the direct impact of specialists on prescribing by general practitioners. DESIGN: Cross-sectional, prescription-based study. SUBJECTS AND SETTING: 88 GPs in the Hunter Urban Division of General Practice, Hunter Valley, NSW. MAIN OUTCOME MEASURE: Proportions of specialist-initiated prescriptions for eight commonly prescribed drug classes. RESULTS: The proportion of specialist-initiated prescriptions was greatest for proton pump inhibitors (85%), and lowest for diuretics (8%), newer antidepressants (10%) and H2-receptor antagonists (13%). Specialists initiated 29% of prescriptions for beta-blockers, 26% for calcium-channel blockers, 20% for statins and 19% for angiotensin-converting enzyme inhibitors or angiotensin II antagonists. Specialists were more likely to have been involved in starting therapy with metoprolol than other beta-blockers (51% v 23%) and diltiazem than other calcium-channel blockers (48% v 19%), and this was related to indication for treatment. In contrast, prescriptions for the more recently introduced drugs (angiotensin II antagonists and atorvastatin) were not more likely to have been specialist-initiated than prescriptions for established angiotensin-converting enzyme inhibitors and statins. CONCLUSIONS: The direct impact of specialists on prescribing in the Hunter Urban Division of General Practice is substantial and varies with the drug class. This highlights the need to engage both GPs and specialists in efforts to improve prescribing practices.

Adult↗
PubMed2001

Statistical issues in analyzing 24-hour dietary recall and 24-hour urine collection data for sodium and potassium intakes.

Dietary recalls and urine assays provide different metrics for assessing sodium and potassium intakes. Means, variances, and correlations of data obtained from these two modes of measurement differ. Pooling of these data is not straightforward, and results from studies employing the different modes may not be comparable. To explore differences between these metrics, the authors used data from the Trial of Nonpharmacologic Intervention in the Elderly (TONE), which included repeated standardized 24-hour dietary recalls and 24-hour urine collections administered over 3 years of follow-up, to estimate sodium and potassium intakes. The authors examined data from 341 control participants assigned to usual care that were collected between August 1992 and December 1995. Dietary recalls yielded estimates of sodium intake that averaged 22% less than those from urine assays and estimates of potassium intake that averaged 16% greater than those from urine assays. Sodium intake estimates were less repeatable (r = 0.22 for diet; r = 0.30 for urine) than potassium intake estimates (r = 0.49 for diet; r = 0.50 for urine), making relations with outcomes more difficult to characterize. Overall, the performance of the two measurement modes was fairly similar across demographic subgroups. Errors in separate estimations of long term sodium and potassium intakes using short term data were strongly correlated, more strongly than the underlying long term intakes of these electrolytes. Because of the correlated measurement error, estimated regression coefficients for linear models including both electrolytes as predictors may be confounded such that the separate relations between these nutrients and outcomes such as blood pressure cannot be reliably estimated by common analytical strategies.

Aged↗
PubMed2001

Site-directed mutagenesis of K396R of the 65 kDa glutamic acid decarboxylase active site obliterates enzyme activity but not antibody binding.

The role of K396 in the enzymatic catalysis and the antigenicity of the 65 kDa isoform of glutamate decarboxylase (GAD65) was analyzed using the K396R GAD65 mutant. GAD65 is a major autoantigen in Type 1 diabetes and autoantibodies directed to GAD65 are widely used markers for this disease. We found that (1) recombinant human GAD65 is fully enzymatically active; (2) the K396R mutation abolished GAD65 activity; and (3) the K396R mutant retained full antigenicity to GAD65 autoantibodies in serum from Type 1 diabetes patients, but not to polyclonal antibodies raised to the catalytic domain.

Amino Acid Sequence↗
PubMed2001

Personal formularies. An index of prescribing quality?

OBJECTIVES: (1) To determine the extent to which Australian general practitioners (GPs) restrict the numbers of agents they prescribe within a drug class ('personal formularies'); (2) To assess concordance of these drug choices with standards based on established guidelines or recognised good prescribing practices; (3) To assess the potential of these measures as indicators of the quality of prescribing. METHODS: Australian Health Insurance Commission (HIC) prescription data (1994 1997) for around 15,400 GPs providing 1500 or more Medicare services per year were analysed. Measures of an individual GP's use of a personal formulary (determined by number of agents) and concordance with prescribing criteria based on specified drugs for five classes of commonly prescribed drugs were derived. RESULTS: Non-steroidal anti-inflammatory drugs (NSAIDs): GP concordance was higher with a non-specified personal formulary (any five NSAIDs) than with a list of specified drugs (five NSAIDs of 'low' or 'medium' risk of gastrointestinal toxicity), and concordance with both increased over time. In 1997, around 70% of GPs used five or fewer NSAIDs for 90% of their prescribing; 47% of GPs had 90% of prescribing from five selected agents. Angiotensin converting enzyme inhibitors/angiotensin-II receptor antagonists: The introduction of new agents appeared to increase the size of the GPs' personal formularies, and concordance with defined standards decreased over time. Antibacterial agents: Concordance with a specified drug standard (nine drugs listed in the Australian Antibiotic Guidelines) increased substantially over time but was largely due to increased prescribing of two heavily promoted drugs. Beta-blocking agents: Over time, GPs restricted most prescribing to two agents, atenolol and metoprolol. Calcium channel blockers: GPs did not appear to restrict prescribing of these drugs; most GPs prescribed all five agents available. CONCLUSIONS: Australian GPs use 'personal formularies'. Formulary size varies with the drug class, can change over time as new agents become available, and its contents can be influenced by promotional activities. Prescribing standards based on numbers of drugs used may not always reflect rational prescribing choices. Criteria based on specified drugs provide more rigorous prescribing standards, but may give a misleading picture of prescribing quality in the absence of information on patients and the indications for treatment. Personal formulary measures are potentially useful prescribing indicators but need to be carefully defined and interpreted. GPs should be encouraged to identify their personal formularies and review the drugs included in them.

Australia↗
PubMed2001

Elementary school-aged children's reports of their health: a cognitive interviewing study.

There are no standard methods for assessing the quality of young children's perceptions of their health and well-being and their ability to comprehend the tasks involved in reporting their health. This research involved three cross-sectional studies using cognitive interviews of 5-11-year-old children (N = 114) to determine their ability to respond to various presentations of pictorially illustrated questions about their health. The samples had a predominance of children in the 5-7-year-old range and families of lower and middle socio-economic status. The research questions in Study 1 involved children's ability to convert their health experiences into scaled responses and relate them to illustrated items (n = 35); Study 2 focused on the type of response format most effectively used by children (n = 19); and Study 3 involved testing children's understanding of health-related terms and use of a specific recall period (n = 60). The results of Study 1 showed that children identified with the cartoon drawing of a child depicted in the illustrated items, typically responding that the child was at or near their own age and of the same gender, with no differences related to race. Study 2 results indicated that children responded effectively to circles of graduated sizes to indicate their response and preferred them to same-size circles or a visual analogue scale. Tests of three-, four-, and five-point response formats demonstrated that children could use them all without confusion. In Study 3, expected age-related differences in understanding were obtained. In fact, the 5-year-old children were unable to understand a sufficient number of items to adequately describe their health. Virtually all children 8 years of age and older were able to fully understand the key terms and presentation of items, used the full five-point range of response options, and accurately used a 4-week recall period. Six- and seven-year-olds were more likely than older children to use only the extreme and middle responses on a five-point scale. No pattern of gender differences in understanding or in use of response options was found. We conclude that children as young as eight are able to report on all aspects of their health experiences and can use a five-point response format. Children aged 6-7 had difficulty with some health-related terms and tended to use extreme responses, but they understood the basic task requirements and were able to report on their health experiences. These results provide the guidance needed to develop and test a pediatric health status questionnaire for children 6-11 years old.

Analysis of Variance↗
PubMed2001

IVF births and pregnancies: an exploration of two methods of assessment using life-table analysis.

PURPOSE: Our purpose was to explore two methods of expressing the performance of IVF programs. METHODS: Using life-table methods, hazard and cure rates and a "monthly fecundability rate" were calculated for an Ontario IVF clinic. The rates were evaluated for their meaningfulness as indicators of the clinic's performance. RESULTS AND CONCLUSIONS: While the hazard rate describes monthly fertility among those who will eventually become pregnant, the fecundability rate describes fertility for all patients who enter the program, making it the more appropriate index for program comparisons. However, from a prospective patient's perspective, both methods are valid indices for summarizing a program's performance.

Birth Rate↗
PubMed2001

Factors associated with expressed satisfaction among people with intellectual disability receiving residential supports.

The aim of the present study was to identify factors associated with variations in the levels of expressed satisfaction among adults with intellectual disability (ID) receiving residential supports. Semi-structured interviews were conducted with 96 people with ID. Forty-five subjects lived in village communities and 51 received community-based residential supports. Ratings were made of the participants' expressed levels of satisfaction in seven domains: (1) their home; (2) daytime activities; (3) social and recreational activities; (4) support from services; (5) friendships and relationships; (6) choices available to them; and (7) risks. The data indicated that: (1) interviewees living in village communities expressed greater satisfaction with friendships and relationships than interviewees living in community-based residential supports; (2) in the other six domains of life satisfaction which were investigated, there were no statistically significant differences between groups; (3) interviewees expressed greater satisfaction with their accommodation and day activities than with friendships, risks and support received; and (4) a wide range of variables relating to the personal characteristics of the interviewees and support received were associated with variations in levels of expressed satisfaction. Variation in the levels of expressed satisfaction was reliably associated with variables relating to the personal characteristics of the interviewees and the nature of the support received.

Adult↗
PubMed2001

Bacterial translocation and immunohistochemical measurement of gut immune function.

AIMS: The local immune response in the small bowel mucosa might play a role in bacterial translocation (BT). The aim of this study was to quantify immune cells and secretory antibodies in the small bowel mucosa, and relate this to BT as assessed by culture of a mesenteric lymph node. METHODS: Immunohistochemical techniques were used to measure the frequency of plasma cells and IgA and IgM positive cells in the lamina propria and semiquantitatively to assess mucosal surface IgA and IgM values in small bowel specimens obtained from 11 patients in whom positive evidence of BT had been identified in a mesenteric lymph node harvested at the time of laparotomy. These were compared with similar specimens obtained from 11 patients in whom a similar lymph node had yielded no growth. RESULTS: BT was associated with a significantly increased median frequency of plasma cells (p < 0.01) and IgA positive cells (p < 0.05) in the lamina propria. The frequency of IgM positive cells was also higher in these patients, although this difference was not significant. In addition, semiquantitatively scored IgA and IgM concentrations at the mucosal surface were both significantly higher in the patients in whom BT had been identified (p = 0.006 and 0.016, respectively). CONCLUSION: Higher numbers of plasma cells and higher IgA and IgM values are present in the small bowel mucosa of patients in whom BT has been shown to occur, suggesting an increased local immune response.

Aged↗