Chronic renal homograft function. Correlation with histology and lymphocyte antigen matching

Renal function was studied in twenty-nine of thirty-four surviving renal allograft recipients from an initial group of sixty-four patients two years after transplantation. Mean clearances of inulin and PAH were, respectively, greater than and equal to half the donors' initial predicted clearances. Minimum urine osmolality during water diuresis was greater, and maximum urine osmolality during hydropenia was less than normal, an effect attributable partly to enhanced solute load in a single transplanted kidney. Patients with compatible donor-recipient lymphocyte antigens demonstrated statistically better function than those with one or more incompatibilities, although there was a definite degree of overlap between the two groups. In contrast, little correlation could be demonstrated between the cumulative histopathology and renal clearances. Renal function in patients with compatible donors was statistically greater than half the donors' initial predicted function. Serial increase in renal clearances was documented in one patient with a compatible donor. Serial decreases were demonstrated in two patients with incompatible donors. These findings suggest that hypertrophy of the denervated, transplanted kidney occurs when immune reaction is minimal. © 1967

Variable strength of forest stand attributes and weather conditions on the questing activity of Ixodes ricinus ticks over years in managed forests

Given the ever-increasing human impact through land use and climate change on the environment, we crucially need to achieve a better understanding of those factors that influence the questing activity of ixodid ticks, a major disease-transmitting vector in temperate forests. We investigated variation in the relative questing nymph densities of Ixodes ricinus in differently managed forest types for three years (2008–2010) in SW Germany by drag sampling. We used a hierarchical Bayesian modeling approach to examine the relative effects of habitat and weather and to consider possible nested structures of habitat and climate forces. The questing activity of nymphs was considerably larger in young forest successional stages of thicket compared with pole wood and timber stages. Questing nymph density increased markedly with milder winter temperatures. Generally, the relative strength of the various environmental forces on questing nymph density differed across years. In particular, winter temperature had a negative effect on tick activity across sites in 2008 in contrast to the overall effect of temperature across years. Our results suggest that forest management practices have important impacts on questing nymph density. Variable weather conditions, however, might override the effects of forest management practices on the fluctuations and dynamics of tick populations and activity over years, in particular, the preceding winter temperatures. Therefore, robust predictions and the detection of possible interactions and nested structures of habitat and climate forces can only be quantified through the collection of long-term data. Such data are particularly important with regard to future scenarios of forest management and climate warming

Investigating the association between obesity and asthma in 6- to 8-year-old Saudi children:a matched case-control study

Background: Previous studies have demonstrated an association between obesity and asthma, but there remains considerable uncertainty about whether this reflects an underlying causal relationship. Aims: To investigate the association between obesity and asthma in pre-pubertal children and to investigate the roles of airway obstruction and atopy as possible causal mechanisms. Methods: We conducted an age- and sex-matched case–control study of 1,264 6- to 8-year-old schoolchildren with and without asthma recruited from 37 randomly selected schools in Madinah, Saudi Arabia. The body mass index (BMI), waist circumference and skin fold thickness of the 632 children with asthma were compared with those of the 632 control children without asthma. Associations between obesity and asthma, adjusted for other potential risk factors, were assessed separately in boys and girls using conditional logistic regression analysis. The possible mediating roles of atopy and airway obstruction were studied by investigating the impact of incorporating data on sensitisation to common aeroallergens and measurements of lung function. Results: BMI was associated with asthma in boys (odds ratio (OR)=1.14, 95% confidence interval (CI), 1.08–1.20; adjusted OR=1.11, 95% CI, 1.03–1.19) and girls (OR=1.37, 95% CI, 1.26–1.50; adjusted OR=1.38, 95% CI, 1.23–1.56). Adjusting for forced expiratory volume in 1 s had a negligible impact on these associations, but these were attenuated following adjustment for allergic sensitisation, particularly in girls (girls: OR=1.25; 95% CI, 0.96–1.60; boys: OR=1.09, 95% CI, 0.99–1.19). Conclusions: BMI is associated with asthma in pre-pubertal Saudi boys and girls; this effect does not appear to be mediated through respiratory obstruction, but in girls this may at least partially be mediated through increased risk of allergic sensitisation

The virtual supermarket: An innovative research tool to study consumer food purchasing behaviour

<p>Abstract</p> <p>Background</p> <p>Economic interventions in the food environment are expected to effectively promote healthier food choices. However, before introducing them on a large scale, it is important to gain insight into the effectiveness of economic interventions and peoples' genuine reactions to price changes. Nonetheless, because of complex implementation issues, studies on price interventions are virtually non-existent. This is especially true for experiments undertaken in a retail setting. We have developed a research tool to study the effects of retail price interventions in a virtual-reality setting: the Virtual Supermarket. This paper aims to inform researchers about the features and utilization of this new software application.</p> <p>Results</p> <p>The Virtual Supermarket is a Dutch-developed three-dimensional software application in which study participants can shop in a manner comparable to a real supermarket. The tool can be used to study several food pricing and labelling strategies. The application base can be used to build future extensions and could be translated into, for example, an English-language version. The Virtual Supermarket contains a front-end which is seen by the participants, and a back-end that enables researchers to easily manipulate research conditions. The application keeps track of time spent shopping, number of products purchased, shopping budget, total expenditures and answers on configurable questionnaires. All data is digitally stored and automatically sent to a web server. A pilot study among Dutch consumers (n = 66) revealed that the application accurately collected and stored all data. Results from participant feedback revealed that 83% of the respondents considered the Virtual Supermarket easy to understand and 79% found that their virtual grocery purchases resembled their regular groceries.</p> <p>Conclusions</p> <p>The Virtual Supermarket is an innovative research tool with a great potential to assist in gaining insight into food purchasing behaviour. The application can be obtained via an URL and is freely available for academic use. The unique features of the tool include the fact that it enables researchers to easily modify research conditions and in this way study different types of interventions in a retail environment without a complex implementation process. Finally, it also maintains researcher independence and avoids conflicts of interest that may arise from industry collaboration.</p

Project FIT: Rationale, design and baseline characteristics of a school- and community-based intervention to address physical activity and healthy eating among low-income elementary school children

<p>Abstract</p> <p>Background</p> <p>This paper describes Project FIT, a collaboration between the public school system, local health systems, physicians, neighborhood associations, businesses, faith-based leaders, community agencies and university researchers to develop a multi-faceted approach to promote physical activity and healthy eating toward the general goal of preventing and reducing childhood obesity among children in Grand Rapids, MI, USA.</p> <p>Methods/design</p> <p>There are four overall components to Project FIT: school, community, social marketing, and school staff wellness - all that focus on: 1) increasing access to safe and affordable physical activity and nutrition education opportunities in the schools and surrounding neighborhoods; 2) improving the affordability and availability of nutritious food in the neighborhoods surrounding the schools; 3) improving the knowledge, self-efficacy, attitudes and behaviors regarding nutrition and physical activity among school staff, parents and students; 4) impacting the 'culture' of the schools and neighborhoods to incorporate healthful values; and 5) encouraging dialogue among all community partners to leverage existing programs and introduce new ones.</p> <p>Discussion</p> <p>At baseline, there was generally low physical activity (70% do not meet recommendation of 60 minutes per day), excessive screen time (75% do not meet recommendation of < 2 hours per day), and low intake of vegetables and whole grains and high intake of sugar-sweetened beverages, French fries and chips and desserts as well as a high prevalence of overweight and obesity (48.5% including 6% with severe obesity) among low income, primarily Hispanic and African American 3^rd-5^thgrade children (n = 403).</p> <p>Trial registration</p> <p><b>ClinicalTrials.gov <a href="http://www.clinicaltrials.gov/ct2/show/NCT01385046">NCT01385046</a></b></p