Simulating the Allocation of Organs for Transplantation

The demand for donated organs greatly exceeds supply and many candidates die awaiting transplantation. Policies for allocating deceased donor organs may address equity of access and medical efficacy, but typically must be implemented with incomplete information. Simulation-based analysis can inform the policy process by predicting the likely effects of alternative policies on a wide variety of outcomes of interest. This paper describes a family of simulations developed by the US Scientific Registry of Transplant Recipients and initial experience in the application of one member of this family, the Liver Simulated Allocation Model (LSAM).     

Racializing narratives: obesity, diabetes and the "Aboriginal" thrifty genotype

This post-colonial reading of narratives of obesity, diabetes, and the hypothesized "thrifty genotype" ascribed to Aboriginal peoples shows how scientific and popular texts support the belief in biological "race." Although the scientific consensus is that "race" is not a empirical category, many scientists use it without comment as a "crude proxy" for presumed genetic differences. The division between science and the social sciences/humanities protects such confusing practices from full scientific and social critique, something interdisciplinary research teams, science studies and improved peer review could provide.     

Alcohol outlets, gonorrhea, and the Los Angeles civil unrest: a longitudinal analysis

This study tests the effect of neighborhood changes on gonorrhea rates. Prior studies that indicate gonorrhea rates are associated with alcohol outlet density and neighborhood deterioration have been cross-sectional and cannot establish causality. After the 1992 Civil Unrest in Los Angeles, 270 alcohol outlets surrendered their licenses due to arson and vandalism thus providing a natural experiment. We geocoded all reported gonorrhea cases from 1988 to 1996 in LA County, all annually licensed alcohol outlets, and all properties damaged as a result of the civil unrest. We ran individual growth models to examine the independent effects of changes in alcohol outlets and damaged buildings on gonorrhea. The individual growth model explained over 90% of the residual variance in census tract gonorrhea rates. After the civil unrest, a unit decrease in the number of alcohol outlets per mile of roadway was associated with 21 fewer gonorrhea cases per 100,000 (p<.01) in tracts affected by the Unrest compared to those not affected. Neighborhood alcohol outlets appear to be significantly associated with changes in gonorrhea rates. The findings suggest that efforts to control sexually transmitted diseases, including gonorrhea and HIV, should address contextual factors that facilitate high-risk behaviors and disease transmission.     

Use of focus groups to understand African-Americans' dietary practices: Implications for modifying a food frequency questionnaire

ObjectiveTo generate information about dietary practices, food preferences and food preparation methods from African-Americans in Macon County, Alabama, as a precursor to an intervention designed to modify an existing dietary health questionnaire (DHQ).MethodAfrican-American males (30) and females (31) ages 20 to 75 years participated in eight focus groups in Macon County Alabama between June and July, 2007.ResultsThe core topics identified were dietary practices; food preferences; food preparation methods; fast food practices; and seasonal/specialty foods. The younger focus group participants reported consuming mostly fast foods such as hamburgers for lunch. Fruits, vegetables, salads, fish, chicken and sandwiches were the most common lunch foods for the older males and females. Across the groups, rice, cornbread and potatoes were reportedly the most commonly consumed starchy foods at dinner. Frying and baking were the most common cooking methods. Fewer participants reported removing the skin when cooking chicken versus those who did not remove. Traditional foods including fried green tomatoes and cracklings were selected for addition to the modified DHQ, while those not commonly consumed, were deleted.ConclusionsParticipants described high-fat traditional food preferences, common frying and addition of salted meats to vegetables, which informed the modification of a DHQ.     

Regional risk factors for health inequalities in Scotland and England and the “Scottish effect”

This paper uses data from the Scottish Health Survey 2003 and the comparable Health Survey for England 2003 to look at whether Scotland's poor health image and mortality profile is reflected in regional inequalities in prevalence of four risk factors for cardiovascular disease: fruit and vegetable consumption, smoking, obesity and diabetes. It also looks at the “Scottish effect” – how much of any difference between and within Scotland and England remains once socio-demographic factors have been taken in to account. The paper then uses regional analyses to determine the extent to which areas within England and Scotland contribute to their national health advantage and disadvantage. All 2003 strategic health authorities in England and Scottish health boards were compared with Greater Glasgow health board as the reference category.The results showed that significant geographic variation in the risk factors remained once individual economic status was taken into account, but the relationship was complex and varied in strength and direction depending upon risk factor involved and gender of respondent. A small number of areas had significantly lower odds of fruit and vegetable consumption of five portions or more a day in men, compared with Greater Glasgow. In contrast some areas had significantly higher odds of fruit and vegetable consumption for women compared with Greater Glasgow.There was greater geographic variation in the odds of smoking in women than in men. Respondents in the south west and southeast of England (areas which usually show health advantage) did not show significantly lower odds of smoking compared with Greater Glasgow once socio-economic variation, age and urban residence was taken into account. It was respondents from central England that had lower odds of smoking than might be expected. Obesity stood out as the single risk factor that had demonstrated a “Scottish effect” in women only.     

Glycoalkaloids in potatoes: Content of glycoalkaloids in potatoes for consumption

Potatoes contain glycoalkaloids in varying levels depending upon variety, treatment and so on. Glycoalkaloids are potentially toxic at the natural levels in potatoes, and Nordic assessments recommend that the safety levels of total glycoalkaloids (TGA) in new potato varieties should not exceed 100 mg/kg. Thus the aim of this study was to make a survey of the distribution and contents of TGA in potatoes on the Danish market, including many different and relevant varieties during a 6-year period. A total of 386 samples of potato tubers were analysed for α-solanine and α-chaconine by extraction with acetic acid and determination by RP-HPLC with UV-detection at 202 nm. The results not only confirmed that contents above 100 mg TGA/kg in potato tubers frequently occurred in some years, but also showed the possibility of finding lower contents in the same varieties other years. This led to the cautious conclusion that by careful selection of varieties and environmental conditions, generally providing consumers with potatoes containing less than 100 mg TGA/kg would be possible.     

Basic Exploratory Research versus Guideline-Compliant Studies Used for Hazard Evaluation and Risk Assessment: Bisphenol A as a Case Study

Background

Myers et al. [Environ Health Perspect 117:309–315 (2009)] argued that Good Laboratory Practices (GLPs) cannot be used as a criterion for selecting data for risk assessment, using bisphenol A (BPA) as a case study. They did not discuss the role(s) of guideline-compliant studies versus basic/exploratory research studies, and they criticized both GLPs and guideline-compliant studies and their roles in formal hazard evaluation and risk assessment. They also specifically criticized our published guideline-compliant dietary studies on BPA in rats and mice and 17β-estradiol (E₂) in mice.

Objectives

As the study director/first author of the criticized E₂ and BPA studies, I discuss the uses of basic research versus guideline-compliant studies, how testing guidelines are developed and revised, how new end points are validated, and the role of GLPs. I also provide an overview of the BPA guideline-compliant and exploratory research animal studies and describe BPA pharmacokinetics in rats and humans. I present responses to specific criticisms by Myers et al.

Discussion and conclusions

Weight-of-evidence evaluations have consistently concluded that low-level BPA oral exposures do not adversely affect human developmental or reproductive health, and I encourage increased validation efforts for “new” end points for inclusion in guideline studies, as well as performance of robust long-term studies to follow early effects (observed in small exploratory studies) to any adverse consequences.     

The Impact of Purple-Flesh Potato (Solanum tuberosum L.) cv. “Shadow Queen” on Minor Health Complaints in Healthy Adults: A Randomized,Double-Blind,Placebo-Controlled Study

The purple-flesh potato (Solanum tuberosum L.) cultivar “Shadow Queen” (SQ) naturally contains anthocyanins. This randomized, double-blind, placebo-controlled study determines whether ingesting purple potatoes increases the number of mesenchymal stem cells (MSC) and improves stress response, a minor health complaint in healthy adults (registration number: UMIN000038876). A total of 15 healthy subjects (ages: 50–70 years) with minor health complaints were randomly assigned to one of two groups. For 8 weeks, the placebo group received placebo potatoes cv. “Haruka” and the test group received test potato cv. SQ containing 45 mg anthocyanin. The MSC count and several stress responses were analyzed at weeks 0 and 8 of the intake periods. The ingestion of a SQ potato did not affect the MSC count but markedly improved psychological stress response, irritability, and depression as minor health complaints compared with “Haruka”. No adverse effects were noted. Hence, an 8-week intake of SQ could improve stress responses.     

Evaluation of Serum Selenium Status by Age and Gender: A Retrospective Observational Cohort Study in Western Romania

Selenium, residing in a series of selenoproteins, plays an important role in both female and male reproductive function. Of particular significance for reproduction is the antioxidant glutathione peroxidase (GPx), a main selenoenzyme, whose level is regulated by the availability of Se in the body. We hypothesized that changes in Se status, closely related to GPx activity, would result in an increased risk of reproductive dysfunction in individuals. We retrospectively investigated the serum selenium (SeS) concentrations of 1264 apparently healthy people, aged 16–89 years, from Western Romania. The general analysis revealed a non-normal SeS distribution with a median SeS of 100.26 ± 18.32 μg/L and a significant difference in SeS levels between age groups. The analysis of the young group (16–35 years) revealed that up to 50% of individuals did not reach the SeS threshold corresponding to maximum GPx activity (80 μg/L), and a significant imbalance between the genders was apparent when looking at SeS values outside the range. Our results correlated with the general diminished reproductive ability registered in Romania during the last few years. Serum selenium content proves to offer a proper reflection of the fertility competence of the young population, and its monitoring is important for guiding dietary adjustments and attaining normal reproductive function.     

Bias in Notifiable Disease Data: A Case Study of Environmental Health in the Philippines

Abstract

The French nuclear power industry contracts out 80% of the maintenance work in its plants to independent companies. The workers in these companies are seldom protected by unions or by government regulations. The average dose of radiation received by such a worker is four times that received by a permanent employee of the contracting entity. As the contract worker approaches a specified dose limit, he is laid off, with no support other than welfare and no compensation for medical expenses that may arise as a result of the radiation exposure or occupational stress. There is a danger that this pattern of worker exploitation will spread as nuclear power plants proliferate around the world.     

Strengthening Sugar-Sweetened Beverage Taxation for Non-Communicable Disease Prevention: A Comparative Political Economy Analysis Case Study of Fiji and Tonga

Diet-related fiscal policy is an effective NCD prevention strategy. However, current sugar-sweetened beverage (SSB) taxes in Fiji and Tonga have not had the desired effect; SSB consumption in Fiji, for example, contributes to mortality more than double the global rates and is highest in the WHO Western Pacific Region. We therefore aimed to better understand the perceived underlying political economy drivers that have and continue to affect change in each country. Our study design utilised a comparative case study that triangulated documentary policy and stakeholder analysis with semi-structured stakeholder interviews in both countries and an in-depth corporate political activity analysis in Fiji. We drew on theoretical frameworks relevant to political economy to collect and analyse policy and stakeholder data, and utilised established corporate political activity frameworks to analyse industry activity. Common findings to both Fiji and Tonga suggested that the SSB tax impact could be increased through multisectoral engagement, embracing a whole-of-society approach, strengthened institutional structures and leveraging off competing priorities across sectors towards more common goals. These findings provide opportunities and lessons for Fiji and Tonga as well as other similar settings seeking to strengthen or upscale the impact of diet-related fiscal policy.     

Pre-Pregnancy Body Mass Index and Risk of Macrosomia and Large for Gestational Age Births with Gestational Diabetes Mellitus as a Mediator: A Prospective Cohort Study in Central China

This study aimed to examine the risk of macrosomia and large for gestational age (LGA) births in relation to maternal pre-pregnancy body mass index (BMI) status mediated through gestational diabetes mellitus (GDM). This prospective study included 34,104 singleton pregnancies at 8–14 weeks of gestation. The interesting outcomes were macrosomia (≥4000 g) and LGA (≥90th percentile). Mediation analyses were conducted using log-binomial regression adjusted for age, education, parity, fetal sex, and gestational weight gain. The proportion mediated was estimated based on the risk difference scale, and the E-value was utilized to assess potential confounders. Overall, 15.9% of women had GDM, and there were 4.0% macrosomia and 9.9% LGA births. The proportion mediated by GDM on macrosomia was up to 40% among obese women, and the estimate of the total effect was 6.18 (95% CI: 5.26–7.26), of the natural direct effect was 4.10 (95% CI: 3.35–4.99), and of the natural indirect effect was 1.51 (95% CI: 1.31–1.76). Likewise, among overweight women, the proportion mediated by GDM on macrosomia was up to 40%. Furthermore, consistent findings were evident for the outcome of LGA births. Pre-pregnancy overweight/obesity increased the risk of macrosomia and LGA births independently and partly mediated by GDM.     

Standardization in laboratory medicine: Adoption of common reference intervals to the Croatian population

Considering the fact that the results of laboratory tests provide useful information about the state of health of patients, determination of reference value is considered an intrinsic part in the development of laboratory medicine. There are still huge differences in the analytical methods used as well as in the associated reference intervals which could consequently significantly affect the proper assessment of patient health. In a constant effort to increase the quality of patients’ care, there are numerous international initiatives for standardization and/or harmonization of laboratory diagnostics in order to achieve maximum comparability of laboratory test results and improve patient safety. Through the standardization and harmonization processes of analytical methods the ability to create unique reference intervals is achieved. Such reference intervals could be applied globally in all laboratories using methods traceable to the same reference measuring system and analysing the biological samples from the populations with similar socio-demographic and ethnic characteristics. In this review we outlined the results of the harmonization processes in Croatia in the field of population based reference intervals for clinically relevant blood and serum constituents which are in accordance with ongoing activity for worldwide standardization and harmonization based on traceability in laboratory medicine.     

Low Adherence to the Mediterranean Diet Is Associated with Poor Socioeconomic Status and Younger Age: A Cross-Sectional Analysis of the EpiDoC Cohort

The Mediterranean diet (MD) is recognized as one of the healthiest dietary patterns as it has been consistently associated with several beneficial health outcomes. Adherence to the MD pattern has been decreasing in southern European countries for the last decades, especially among low socioeconomic groups. The aim of this study was to assess the adherence to the MD in Portugal, to evaluate regional differences, and explore associated factors (sociodemographic, economic, and lifestyles behaviors). This study used the third data collection wave of the Epidemiology of Chronic Diseases Cohort Study (EpiDoC 3). MD adherence was assessed using the Portuguese-validated MD adherence score (MEDAS) questionnaire. Non-adjusted and adjusted logistic regression models were used to assess the risk factors for low MD adherence and individual MEDAS items. In this cross-sectional evaluation of the EpiDoC 3 cohort study (n = 5647), 28.8% of the Portuguese population had low adherence to a MD. Azores and Madeira had lower adherence to the MD than the rest of the country. Younger individuals in lower income categories (e.g., OR_{finding it very difficult} = 1.48; 95% CI 1.16–1.91) and with a lower educational level (e.g., OR_{0–4 years} = 2.63; 95% CI 2.09–3.32) had higher odds of having a lower adherence to the MD. Portuguese adults have a high prevalence of low adherence to the MD, especially among those who are younger and have lower socioeconomic status. Public health policies to promote adherence to the MD should pay special attention to these groups.     

Depressive Symptoms in Middle-Aged and Elderly Women Are Associated with a Low Intake of Vitamin B6: A Cross-Sectional Study

This study investigated the nutritional factors that are associated with anxiety and depressive symptoms in Japanese middle-aged and elderly women. We conducted a cross-sectional study with 289 study participants aged ≥40 years (mean age = 52.0 ± 6.9 years). Their dietary habits, menopausal status and symptoms, and varied background factors, such as body composition, lifestyle factors, and cardiovascular parameters, were assessed. Their anxiety and depressive symptoms were evaluated using the Hospital Anxiety and Depression Scale (HADS), where scores of 0–7 points, 8–10 points, and 11–21 points on either the anxiety or depression subscales were categorized as mild, moderate, and severe, respectively. The dietary consumption of nutrients was assessed using a brief self-administered diet history questionnaire. The relationships between the moderate-to-severe anxiety/depressive symptoms and the dietary intake of 43 major nutrients were investigated using multivariate logistic regression analyses. After adjusting for age, menopausal status, and the background factors that were significantly related to depressive symptoms, moderate and severe depression was significantly inversely associated with only vitamin B6 (adjusted odds ratio per 10 μg/MJ in vitamin B6 intake = 0.89, 95% confidence interval = 0.80–0.99). A higher intake of vitamin B6 could help relieve depressive symptoms for this population.     

An fMRI Investigation into the Effects of Ketogenic Medium-Chain Triglycerides on Cognitive Function in Elderly Adults: A Pilot Study

Evidence suggests that oral intake of medium-chain triglycerides (MCTs), which promote the production of ketone bodies, may improve cognitive functions in elderly people; however, the underlying brain mechanisms remain elusive. We tested the hypothesis that cognitive improvement accompanies physiological changes in the brain and reflects the use of ketone bodies as an extra energy source. To this end, by using functional magnetic resonance imaging, cerebral blood oxygenation level-dependent (BOLD) signals were measured while 20 healthy elderly subjects (14 females and 6 males; mean age: 65.7 ± 3.9 years) were engaged in executive function tasks (N-back and Go-Nogo) after ingesting a single MCT meal (Ketonformula^®) or placebo meal in a randomized, double-blind placebo-controlled design (UMIN000031539). Morphological characteristics of the brain were also examined in relation to the effects of an MCT meal. The MCT meal improved N-back task performance, and this was prominent in subjects who had reduced grey matter volume in the dorsolateral prefrontal cortex (DLPFC), a region known to promote executive functions. When the participants were dichotomized into high/low level groups of global cognitive function at baseline, the high group showed improved N-back task performance, while the low group showed improved Go-Nogo task performance. This was accompanied by decreased BOLD signals in the DLPFC, indicative of the consumption of ketone bodies as an extra energy source.