Cellular,synaptic, and biochemical features of resilient cognition in Alzheimer's disease

Although neuritic plaques and neurofibrillary tangles in older adults are correlated with cognitive impairment and severity of dementia, it has long been recognized that the relationship is imperfect, as some people exhibit normal cognition despite high levels of Alzheimer's disease (AD) pathology. We compared the cellular, synaptic, and biochemical composition of midfrontal cortices in female subjects from the Religious Orders Study who were stratified into three subgroups: (1) pathological AD with normal cognition (“AD-Resilient”), (2) pathological AD with AD-typical dementia (“AD-Dementia”), and (3) pathologically normal with normal cognition (“Normal Comparison”). The AD-Resilient group exhibited preserved densities of synaptophysin-labeled presynaptic terminals and synaptopodin-labeled dendritic spines compared with the AD-Dementia group, and increased densities of glial fibrillary acidic protein astrocytes compared with both the AD-Dementia and Normal Comparison groups. Further, in a discovery-type antibody microarray protein analysis, we identified a number of candidate protein abnormalities that were associated with a particular diagnostic group. These data characterize cellular and synaptic features and identify novel biochemical targets that may be associated with resilient cognitive brain aging in the setting of pathological AD.     

Food insecurity and mental health: Surprising trends among community health volunteers in Addis Ababa,Ethiopia during the 2008 food crisis

The 2008 food crisis may have increased household food insecurity and caused distress among impoverished populations in low-income countries. Policy researchers have attempted to quantify the impact that a sharp rise in food prices might have on population wellbeing by asking what proportion of households would drop below conventional poverty lines given a set increase in prices. Our understanding of the impact of food crises can be extended by conducting micro-level ethnographic studies. This study examined self-reported household food insecurity (FI) and common mental disorders (CMD) among 110 community health AIDS care volunteers living in Addis Ababa, Ethiopia during the height of the 2008 food crisis. We used generalized estimating equations that account for associations between responses given by the same participants over 3 survey rounds during 2008, to model the longitudinal response profiles of FI, CMD symptoms, and socio-behavioral and micro-economic covariates. To help explain the patterns observed in the response profiles and regression results, we examine qualitative data that contextualize the cognition and reporting behavior of AIDS care volunteers, as well as potential observation biases inherent in longitudinal, community-based research. Our data show that food insecurity is highly prevalent, that is it associated with household economic factors, and that it is linked to mental health. Surprisingly, the volunteers in this urban sample did not report increasingly severe FI or CMD during the peak of the 2008 food crisis. This is a counter-intuitive result that would not be predicted in analyses of population-level data such as those used in econometrics simulations. But when these results are linked to real people in specific urban ecologies, they can improve our understanding of the psychosocial consequences of food price shocks.     

Home and community based care program assessment for people living with HIV/AIDS in Arba Minch, Southern Ethiopia

Background

Homeless populations have complex and diverse end-of-life care needs. However, they typically die outside of the end-of-life care system. To date, few studies have explored barriers to the end-of-life care system for homeless populations. This qualitative study involving health and social services professionals from across Canada sought to identify barriers to the end-of-life care system for homeless populations and generate recommendations to improve their access to end-of-life care.

Methods

Semi-structured qualitative interviews were conducted with 54 health and social services professionals involved in end-of-life care services delivery to homeless persons in six Canadian cities (Halifax, Hamilton, Ottawa, Thunder Bay, Toronto and Winnipeg). Participants included health administrators, physicians, nurses, social workers, harm reduction specialists, and outreach workers. Interviews were audio-recorded, transcribed verbatim and analysed thematically.

Results

Participants identified key barriers to end-of-life care services for homeless persons, including: (1) insufficient availability of end-of-life care services; (2) exclusionary operating procedures; and, (3) poor continuity of care. Participants identified recommendations that they felt had the potential to minimize these barriers, including: (1) adopting low-threshold strategies (e.g. flexible behavioural policies and harm reduction strategies); (2) linking with population-specific health and social care providers (e.g. emergency shelters); and, (3) strengthening population-specific training.

Conclusions

Homeless persons may be underserved by the end-of-life care system as a result of barriers that they face to accessing end-of-life care services. Changes in the rules and regulations that reflect the health needs and circumstances of homeless persons and measures to improve continuity of care have the potential to increase equity in the end-of-life care system for this underserved population.     

Diversity and disparity in dementia: the impact of ethnoracial differences in Alzheimer disease

Debate exists regarding differences in the prevalence of Alzheimer disease (AD) in African Americans and Hispanics in the United States, with some evidence suggesting that the prevalence of AD may be considerably higher in these groups than in non-Hispanic whites. Despite this possible disparity, patients of minority ethnoracial groups often receive delayed diagnosis or inadequate treatment for dementia. This review investigates these disparities by conceptualizing the dementia disease process as a product of both biological and cultural factors. Ethnoracial differences in biological risk factors, such as genetics and cardiovascular disease, may help to explain disparities in the incidence and prevalence of AD, whereas race-specific cultural factors may impact diagnosis and treatment. Cultural factors include differences in perceptions about what is normal aging and what is not, lack of adequate access to medical care, and issues of trust between minority groups and the medical establishment. The diagnosis of AD in diverse populations may also be complicated by racial biases inherent in cognitive screening tools widely used by clinicians, but controlling for literacy level or using savings scores in psychometric analyses has the potential to mitigate these biases. We also suggest that emerging biomarker-based diagnostic tools may be useful in further characterizing diverse populations with AD. Recognizing the gap in communication that exists between minority communities and the medical research community, we propose that education and outreach are a critical next step in the effort to understand AD as it relates to diverse populations.     

The influence of father's child feeding knowledge and practices on children's dietary diversity: a study in urban and rural districts of Northern Ethiopia, 2013

Infant and young child feeding has been recognised as an essential element to improve growth of children, especially in developing countries where malnutrition among children and its dire consequences are very prevalent. However, little attention has been paid on the influence of fathers on child feeding practices, although fathers are very important in raising well‐adjusted, happy and successful children. Therefore, this study aimed to assess the influence of fathers' child feeding knowledge and practice on children's dietary diversity. A community‐based comparative cross‐sectional study was conducted among 850 eligible urban and rural households with children of 6–23 months. The father and mother of the child were interviewed on children's dietary diversity and fathers' knowledge and practice of child feeding. Nearly half (46%) of the children in the rural district did not meet the minimum dietary diversity, and in the urban district, the rate was even worse (72%). Grains were the common food group given to the children in both districts, whereas flesh food was the least commonly consumed food group. Additionally, low vitamin A‐rich food and other fruit and vegetable consumption seem to be a problem in both districts. Almost all dimensions of fathers' knowledge and practice were significantly related to children's minimum dietary diversity; especially, fathers' knowledge of food groups was an important predictor (P‐value < 0.001) in both districts. Interventions that focus on the fathers' knowledge of child feeding, especially about food groups, are recommended to improve children's dietary diversity in the study communities.     

Intranasal immunization strategy to impede pilin-mediated binding of Pseudomonas aeruginosa to airway epithelial cells

Prevention of pulmonary Pseudomonas aeruginosa infections represents a critical unmet medical need for cystic fibrosis (CF) patients. We have examined the tenet that a mucosal immunization approach can reduce interactions of a piliated form of this opportunistic pathogen with respiratory epithelial cells. Vaccinations were performed using ntPEpilinPAK, a protein chimera composed of a nontoxic form of P. aeruginosa exotoxin A (ntPE), where the C-terminal loop amino acid sequence of the PAK strain pilin protein was inserted in place of the ntPE Ib domain. Intranasal (i.n.) immunization of BALB/c mice with ntPEpilinPAK generated both serum and saliva immune responses. A series of in vitro studies showed that diluted samples of saliva obtained from immunized mice reduced pilin-dependent P. aeruginosa binding to polarized human tracheal epithelial cells, protected human pulmonary epithelial cells from cytotoxic actions associated with bacterial challenge, and reduced exotoxin A toxicity. Overall, i.n. administration of ntPEpilinPAK induced mucosal and systemic immune responses that may be beneficial for blocking early stage adhesion and/or infection events of epithelial cell-P. aeruginosa interactions at oropharyngeal surfaces.