Plos One
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Cerebrospinal fluid (CSF) dynamics in the cervical spinal subarachnoid space (SSS) have been thought to be important to help diagnose and assess craniospinal disorders such as Chiari I malformation (CM). In this study we obtained time-resolved three directional velocity encoded phase-contrast MRI (4D PC MRI) in three healthy volunteers and four CM patients and compared the 4D PC MRI measurements to subject-specific 3D computational fluid dynamics (CFD) simulations. The CFD simulations considered the geometry to be rigid-walled and did not include small anatomical structures such as nerve roots, denticulate ligaments and arachnoid trabeculae. ⋯ This study represents the first comparison of 4D PC MRI measurements to CFD of CSF flow in the cervical SSS. The results highlight the utility of 4D PC MRI for evaluation of complex CSF dynamics and the need for improvement of CFD methodology. Future studies are needed to investigate whether integration of fine anatomical structures and gross motion of the brain and/or spinal cord into the computational model will lead to a better agreement between the two techniques.
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Given the polymicrobial nature of pulmonary infections in patients with cystic fibrosis (CF), it is essential to enhance our knowledge on the composition of the microbial community to improve patient management. In this study, we developed a pyrosequencing approach to extensively explore the diversity and dynamics of fungal and prokaryotic populations in CF lower airways. ⋯ In light of the recent concept of CF lung microbiota, we viewed the microbial community as a unique pathogenic entity. We thus interpreted our results to highlight the potential interactions between microorganisms and the role of fungi in the context of improving survival in CF.
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To describe trends in the incidence of non-traumatic amputations among people with and without diabetes and estimate the relative risk of an individual with diabetes undergoing a lower extremity amputation compared to an individual without diabetes in the Republic of Ireland. ⋯ This study provides the first national estimate of lower extremity amputation rates in the Republic of Ireland. Diabetes-related amputation rates have remained steady despite an increase in people with diabetes. These estimates provide a base-line and will allow follow-up over time.
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Vaccination against hepatitis B virus is an effective and routine practice that can prevent infection. However, vaccine-induced immunity to hepatitis B varies among individuals. CD4(+) T helper cells, which play an important role in both cellular and humoral immunity, are involved in the immune response elicited by vaccination. ⋯ The minor allele 'C' of rs12133337 continued to show an association with a lower response to hepatitis B vaccination (P = 0.033, odds radio = 1.28, 95% confidence interval = 1.01-1.61). Furthermore, in the stratified analysis for both the first and second populations, the association of the minor allele 'C' of rs12133337 with a lower response to hepatitis B vaccination was more prominent after individuals who were overweight or obese (body mass index ≥25 kg/m(2)) were excluded (1(st) stage: P = 0.003, 2(nd) stage: P = 0.002, P-combined = 9.47e-5). These findings suggest that the rs12133337 polymorphism in the CD3Z gene might affect the immune response to hepatitis B vaccination, and that a lower BMI might increase the contribution of the polymorphism to immunity to hepatitis B vaccination.
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This study investigates strategies in reasoning about mental states of others, a process that requires theory of mind. It is a first step in studying the cognitive basis of such reasoning, as strategies affect tradeoffs between cognitive resources. Participants were presented with a two-player game that required reasoning about the mental states of the opponent. ⋯ Later in games, the probabilities of forward and backward progressions are similar, which seems to imply that participants were either applying backward reasoning or jumping back to previous decision points while applying forward reasoning. Thus, the game-theoretical favorite strategy, backward reasoning, does seem to exist in human reasoning. However, participants preferred the more familiar, practiced, and prevalent strategy: forward reasoning.