8 research outputs found

    The weaker sex: Male lingcod (Ophiodon elongatus) with blue color polymorphism are more burdened by parasites than are other sex–color combinations

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    The unusual blue color polymorphism of lingcod (Ophiodon elongatus) is the subject of much speculation but little empirical research; ~20% of lingcod individuals exhibit this striking blue color morph, which is discrete from and found within the same populations as the more common brown morph. In other species, color polymorphisms are intimately linked with host–parasite interactions, which led us to ask whether blue coloration in lingcod might be associated with parasitism, either as cause or effect. To test how color and parasitism are related in this host species, we performed parasitological dissection of 89 lingcod individuals collected across more than 26 degrees of latitude from Alaska, Washington, and California, USA. We found that male lingcod carried 1.89 times more parasites if they were blue than if they were brown, whereas there was no difference in parasite burden between blue and brown female lingcod. Blue individuals of both sexes had lower hepatosomatic index (i.e., relative liver weight) values than did brown individuals, indicating that blueness is associated with poor body condition. The immune systems of male vertebrates are typically less effective than those of females, due to the immunocompromising properties of male sex hormones; this might explain why blueness is associated with elevated parasite burdens in males but not in females. What remains to be determined is whether parasites induce physiological damage that produces blueness or if both blue coloration and parasite burden are driven by some unmeasured variable, such as starvation. Although our study cannot discriminate between these possibilities, our data suggest that the immune system could be involved in the blue color polymorphism–an exciting jumping-off point for future research to definitively identify the cause of lingcod blueness and a hint that immunocompetence and parasitism may play a role in lingcod population dynamics

    D-CARE: The Dementia Care Study: Design of a Pragmatic Trial of the Effectiveness and Cost Effectiveness of Health System-Based Versus Community-Based Dementia Care Versus Usual Dementia Care.

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    Background/objectivesAlthough several approaches have been developed to provide comprehensive care for persons living with dementia (PWD) and their family or friend caregivers, the relative effectiveness and cost effectiveness of community-based dementia care (CBDC) versus health system-based dementia care (CBDC) and the effectiveness of both approaches compared with usual care (UC) are unknown.DesignPragmatic randomized three-arm superiority trial. The unit of randomization is the PWD/caregiver dyad.SettingFour clinical trial sites (CTSs) based in academic and clinical health systems.ParticipantsA total of 2,150 English- or Spanish-speaking PWD who are not receiving hospice or residing in a nursing home and their caregivers.InterventionsEighteen months of (1) HSDC provided by a nurse practitioner or physician's assistant dementia care specialist who works within the health system, or (2) CBDC provided by a social worker or nurse care consultant who works at a community-based organization, or (3) UC with as needed referral to the Alzheimer's Association Helpline.MeasurementsPrimary outcomes: PWD behavioral symptoms and caregiver distress as measured by the Neuropsychiatric Inventory Questionnaire (NPI-Q) Severity and Modified Caregiver Strain Index scales.Secondary outcomesNPI-Q Distress, caregiver unmet needs and confidence, and caregiver depressive symptoms. Tertiary outcomes: PWD long-term nursing home placement rates, caregiver-reported PWD functional status, cognition, goal attainment, "time spent at home," Dementia Burden Scale-Caregiver, a composite measure of clinical benefit, Quality of Life of persons with dementia, Positive Aspects of Caregiving, and cost effectiveness using intervention costs and Medicare claims.ResultsThe results will be reported in the spring of 2024.ConclusionD-CARE will address whether emphasis on clinical support and tighter integration with other medical services has greater benefit than emphasis on social support that is tied more closely to community resources. It will also assess the effectiveness of both interventions compared with UC and will evaluate the cost effectiveness of each intervention

    Proceedings from the 9th annual conference on the science of dissemination and implementation

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    Proceedings from the 9th annual conference on the science of dissemination and implementation

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