20 research outputs found
CADASIL accelerated by acute hypotension: Arterial and venous contribution to leukoaraiosis
Objective: To underline the importance of blood pressure regulation in cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) and to describe changes that occur in the veins in this condition, specifically venous collagenosis associated with leukoaraiosis. Methods: Case report with neuroimaging and pathologic data. Results: A 61-year-old man with genetically confirmed CADASIL was initially lucid following a motor vehicle accident but subsequently became hypotensive (60/40 mm Hg) due to an open femur fracture and required intubation. Multiple new white matter infarcts appeared on brain imaging. A second hypotensive episode days later was associated with new coin-sized infarcts in the bilateral corona radiata and cerebellar peduncles, and resulted in quadriplegia. No embolic source was found on cardiac or vascular imaging. He died 5 weeks post trauma. Autopsy revealed extensive subcortical and periventricular leukoencephalopathy and multiple cavitations involving deep subcortical gray and white matter. Small arteries had thickened walls, disruption of the muscularis, and intimal periodic acid-Schiff (PAS)-positive material. Both larger periventricular and small caliber veins had thickened walls that were PAS-negative and trichrome-positive, consistent with venous collagenosis. There was no pathologic evidence of global hypoxia or diffuse axonal injury. Conclusions: The findings suggest rapid acceleration of CADASIL pathology from acute hypotension in the setting of impaired vasoreactivity. In addition, collagenosis of veins in the affected white matter regions suggests that the veins may play an important, though largely overlooked, role in maintaining white matter integrity
The role of biofactors in the prevention and treatment of age‐related diseases
The present demographic changes toward an aging society caused a rise in the number of senior citizens and the incidence and burden of age‐related diseases (such as cardiovascular diseases [CVD], cancer, nonalcoholic fatty liver disease [NAFLD], diabetes mellitus, and dementia), of which nearly half is attributable to the population ≥60 years of age. Deficiencies in individual nutrients have been associated with increased risks for age‐related diseases and high intakes and/or blood concentrations with risk reduction. Nutrition in general and the dietary intake of essential and nonessential biofactors is a major determinant of human health, the risk to develop age‐related diseases, and ultimately of mortality in the older population. These biofactors can be a cost‐effective strategy to prevent or, in some cases, even treat age‐related diseases. Examples reviewed herein include omega‐3 fatty acids and dietary fiber for the prevention of CVD, α‐tocopherol (vitamin E) for the treatment of biopsy‐proven nonalcoholic steatohepatitis, vitamin D for the prevention of neurodegenerative diseases, thiamine and α‐lipoic acid for the treatment of diabetic neuropathy, and the role of folate in cancer epigenetics. This list of potentially helpful biofactors in the prevention and treatment of age‐related diseases, however, is not exhaustive and many more examples exist. Furthermore, since there is currently no generally accepted definition of the term biofactors , we here propose a definition that, when adopted by scientists, will enable a harmonization and consistent use of the term in the scientific literature
Molecular Architectures of Trimeric SIV and HIV-1 Envelope Glycoproteins on Intact Viruses: Strain-Dependent Variation in Quaternary Structure
The initial step in target cell infection by human, and the closely related simian immunodeficiency viruses (HIV and SIV, respectively) occurs with the binding of trimeric envelope glycoproteins (Env), composed of heterodimers of the viral transmembrane glycoprotein (gp41) and surface glycoprotein (gp120) to target T-cells. Knowledge of the molecular structure of trimeric Env on intact viruses is important both for understanding the molecular mechanisms underlying virus-cell interactions and for the design of effective immunogen-based vaccines to combat HIV/AIDS. Previous analyses of intact HIV-1 BaL virions have already resulted in structures of trimeric Env in unliganded and CD4-liganded states at ∼20 Å resolution. Here, we show that the molecular architectures of trimeric Env from SIVmneE11S, SIVmac239 and HIV-1 R3A strains are closely comparable to that previously determined for HIV-1 BaL, with the V1 and V2 variable loops located at the apex of the spike, close to the contact zone between virus and cell. The location of the V1/V2 loops in trimeric Env was definitively confirmed by structural analysis of HIV-1 R3A virions engineered to express Env with deletion of these loops. Strikingly, in SIV CP-MAC, a CD4-independent strain, trimeric Env is in a constitutively “open” conformation with gp120 trimers splayed out in a conformation similar to that seen for HIV-1 BaL Env when it is complexed with sCD4 and the CD4i antibody 17b. Our findings suggest a structural explanation for the molecular mechanism of CD4-independent viral entry and further establish that cryo-electron tomography can be used to discover distinct, functionally relevant quaternary structures of Env displayed on intact viruses
The Molecular Identification of Organic Compounds in the Atmosphere: State of the Art and Challenges
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Soluble Epoxide Hydrolase-Derived Linoleic Acid Oxylipins in Serum Are Associated with Periventricular White Matter Hyperintensities and Vascular Cognitive Impairment.
White matter hyperintensities (WMH) are presumed to indicate subcortical ischemic vascular disease but their underlying pathobiology remains incompletely understood. The soluble epoxide hydrolase (sEH) enzyme converts anti-inflammatory and vasoactive cytochrome p450-derived polyunsaturated fatty acid epoxides into their less active corresponding diol species. Under the hypothesis that the activity of sEH might be associated with subcortical ischemic vascular disease and vascular cognitive impairment, this study aimed to compare the relative abundance of sEH substrates and products in peripheral blood between patients with extensive WMH (discovered due to transient ischemic attack; n = 29) and healthy elderly with minimal WMH (n = 25). The concentration of 12,13-DiHOME (a sEH-derived linoleic acid metabolite), and the ratio of 12,13-DiHOME to its sEH substrate, 12,13-EpOME, were elevated in the extensive WMH group (F1,53 = 5.9, p = 0.019), as was the 9,10-DiHOME/9,10-EpOME ratio (F1,53 = 5.4, p = 0.024). The 12,13-DiHOME/12,13-EpOME ratio was associated with poorer performance on a composite score derived from tests of psychomotor processing speed, attention, and executive function (β = - 0.473, p = 0.001, adjusted r2 = 0.213), but not with a composite verbal memory score. In a mediation model, periventricular WMH (but not deep WMH), explained 37% of the effect of the 12,13-DiHOME/12,13-EpOME ratio on the speed/attention/executive function composite score (indirect effect = - 0.50, 95% bootstrap confidence interval [- 0.99, - 0.17] Z-score units). Serum oxylipin changes consistent with higher sEH activity were markers of vascular cognitive impairment, and this association was partly explained by injury to the periventricular subcortical white matter
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Soluble Epoxide Hydrolase-Derived Linoleic Acid Oxylipins in Serum Are Associated with Periventricular White Matter Hyperintensities and Vascular Cognitive Impairment.
White matter hyperintensities (WMH) are presumed to indicate subcortical ischemic vascular disease but their underlying pathobiology remains incompletely understood. The soluble epoxide hydrolase (sEH) enzyme converts anti-inflammatory and vasoactive cytochrome p450-derived polyunsaturated fatty acid epoxides into their less active corresponding diol species. Under the hypothesis that the activity of sEH might be associated with subcortical ischemic vascular disease and vascular cognitive impairment, this study aimed to compare the relative abundance of sEH substrates and products in peripheral blood between patients with extensive WMH (discovered due to transient ischemic attack; n = 29) and healthy elderly with minimal WMH (n = 25). The concentration of 12,13-DiHOME (a sEH-derived linoleic acid metabolite), and the ratio of 12,13-DiHOME to its sEH substrate, 12,13-EpOME, were elevated in the extensive WMH group (F1,53 = 5.9, p = 0.019), as was the 9,10-DiHOME/9,10-EpOME ratio (F1,53 = 5.4, p = 0.024). The 12,13-DiHOME/12,13-EpOME ratio was associated with poorer performance on a composite score derived from tests of psychomotor processing speed, attention, and executive function (β = - 0.473, p = 0.001, adjusted r2 = 0.213), but not with a composite verbal memory score. In a mediation model, periventricular WMH (but not deep WMH), explained 37% of the effect of the 12,13-DiHOME/12,13-EpOME ratio on the speed/attention/executive function composite score (indirect effect = - 0.50, 95% bootstrap confidence interval [- 0.99, - 0.17] Z-score units). Serum oxylipin changes consistent with higher sEH activity were markers of vascular cognitive impairment, and this association was partly explained by injury to the periventricular subcortical white matter
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The dementia-inclusive choices in exercise project: using participatory action research to improve physical activity supports for persons with dementia
Persons with dementia have the right to equal inclusion in rehabilitation, including physical activity. However, the perspectives of persons with dementia are rarely integrated into decision-making related to physical activity programming, services, and supports. Here, we describe the participatory action research (PAR) approach used to develop the Dementia-Inclusive Choices for Exercise (DICE) toolkit, which aims to increase the quality and number of physical activity opportunities available to persons with dementia. The DICE Research Team included persons with dementia, a family care partner, exercise professionals, community and dementia service providers, health care professionals, and researchers who worked to: 1) Engage/maintain the Research Team; 2) Set/ navigate ways of engagement; 3) Understand barriers to physical activity; 4) Prioritize the audience and actions; 5) Develop the toolkit; 6) Conduct usability testing; and 7) Implement and evaluate. Guided by the Behaviour Change Wheel, and informed by interviews, focus groups, and existing research, our PAR Team chose to prioritize training exercise providers; exercise providers can enable exercise for persons with dementia if they understand common changes with dementia and how to support persons with dementia in exercise. The content and format of the toolkit was co- developed: drafted by our Research Team, adapted through a stakeholder workshop, and refined through iterative development and usability testing. The product of our PAR process, the DICE toolkit, includes videos meant to destigmatize dementia, training modules and a training manual for exercise providers, a physical activity handout for persons with dementia, and wallet cards to help persons with dementia communicate their abilities, needs, and preferences. Our usability study indicated that the toolkit could be used by exercise providers and may improve attitudes about dementia. Our vision is that our co-developed DICE toolkit will empower exercise providers to improve physical activity opportunities and support for persons with dementia