Cholesterol metabolism: A review of how ageing disrupts the biological mechanisms responsible for its regulation

Cholesterol plays a vital role in the human body as a precursor of steroid hormones and bile acids, in addition to providing structure to cell membranes. Whole body cholesterol metabolism is maintained by a highly coordinated balancing act between cholesterol ingestion, synthesis, absorption, and excretion. The aim of this review is to discuss how ageing interacts with these processes. Firstly, we will present an overview of cholesterol metabolism. Following this, we discuss how the biological mechanisms which underpin cholesterol metabolism are effected by ageing. Included in this discussion are lipoprotein dynamics, cholesterol absorption/synthesis and the enterohepatic circulation/synthesis of bile acids. Moreover, we discuss the role of oxidative stress in the pathological progression of atherosclerosis and also discuss how cholesterol biosynthesis is effected by both the mammalian target of rapamycin and sirtuin pathways. Next, we examine how diet and alterations to the gut microbiome can be used to mitigate the impact ageing has on cholesterol metabolism. We conclude by discussing how mathematical models of cholesterol metabolism can be used to identify therapeutic interventions

Neighborhood-level socioeconomic and urban land use risk factors of canine leptospirosis: 94 cases (2002–2009)

Associations of housing, population, and agriculture census variables, and presence near public places were retrospectively evaluated as potential risk factors for canine leptospirosis using Geographic Information Systems (GIS). The sample population included 94 dogs positive for leptospirosis based on a positive polymerase chain reaction test for leptospires on urine, isolation of leptospires on urine culture, a single reciprocal serum titer of 12,800 or greater, or a four-fold rise in reciprocal serum titers over a 2–4 week period; and 185 dogs negative for leptospirosis based on a negative polymerase chain reaction test and reciprocal serum titers less than 400. Multivariable logistic regressions revealed different risk factors among different census units; however, houses lacking complete plumbing facilities [OR = 2.80, 95% C.I. = 1.82, 4.32 (census unit, block group); OR = 1.36, 95% C.I. = 1.28, 1.45 (census tract); OR = 3.02, 95% C.I. = 2.60, 3.52 (county)]; and poverty status by age (18–64) [OR = 2.04, 95% C.I. = 1.74, 2.39 (block group); OR = 1.53, 95% C.I. = 1.41, 1.67 (census tract); and OR = 1.62, 95% C.I. = 1.50, 1.76 (county)] were consistent risk factors for all census units. Living within 2500 m of a university/college and parks/forests were also significantly associated with leptospirosis status in dogs. Dogs that live under these circumstances are at higher risk for leptospirosis and pet owners should consider vaccination

Beyond dressing and driving: Using occupation to facilitate community integration in neurorehabilitation

During the process of community integration, individuals with acquired brain injury may experience difficulties in all areas of occupational performance including self-care, home management, community access, leisure, social activities and vocational pursuits. Community based rehabilitation services provide opportunities to minimise such difficulties by working with clients as they engage in meaningful real-life context-based occupations. The therapeutic use of occupation is at the core of occupational therapy practice. We reflect on the nature and principles of occupation and highlight particular benefits for facilitating community integration after brain injury. This is illustrated using the example of executive dysfunction. Several challenges for the occupational therapy profession arise from the shift in focus from hospital to community based rehabilitation, and the need for further research on community integration after brain injury from an occupational perspective is recognised