Theories of adult brain development, based on neuropsychological test results and structural neuroimaging, suggest differential rates of age‐related change in function across cortical and subcortical sub‐regions. However, it remains unclear if these trends also extend to the aging dopamine system. Here we examined cross‐sectional adult age differences in estimates of D2‐like receptor binding potential across several cortical and subcortical brain regions using PET imaging and the radiotracer [18F]Fallypride in two samples of healthy human adults (combined N = 132). After accounting for regional differences in overall radioligand binding, estimated percent difference in receptor binding potential by decade (linear effects) were highest in most temporal and frontal cortical regions (~6–16% per decade), moderate in parahippocampal gyrus, pregenual frontal cortex, fusiform gyrus, caudate, putamen, thalamus, and amygdala (~3–5%), and weakest in subcallosal frontal cortex, ventral striatum, pallidum, and hippocampus (~0–2%). Some regions showed linear effects of age while many showed curvilinear effects such that binding potential declined from young adulthood to middle age and then was relatively stable until old age. Overall, these data indicate that the rate and pattern of decline in D2 receptor availability is regionally heterogeneous. However, the differences across regions were challenging to organize within existing theories of brain development and did not show the same pattern of regional change that has been observed in gray matter volume, white matter integrity, or cognitive performance. This variation suggests that existing theories of adult brain development may need to be modified to better account for the spatial dynamics of dopaminergic system aging. 相似文献
Cardiovascular disease represents a significant portion of pregnancy‐related complications and is associated with high rates of morbidity and mortality in this cohort. Cardiac valvulopathy, and aortic valve pathologies, in particular, pose a significant challenge to women who are pregnant and to the health care professionals who look after them. Depending on the type and severity of aortic valve pathology, pregnancy may exacerbate or accelerate the progression of valvulopathy sequelae because of the hemodynamic changes that occur from conception, throughout gestation, up to Labor and postpartum. Management of such patients ranges from basic conservative measures such as bed‐rest, extending to high‐risk emergency open heart surgery. This nonstructured review aims to highlight the current evidence available relating to the management of aortic valve disease in pregnancy, with a key focus on cases which requires intervention beyond that of medical therapy. In conclusion, the management of aortic valvulopathy in pregnancy is a challenging field with only a small amount of clinical experience and retrospective study supporting evidence‐based decisions in this field. A greater understanding of the most recent advances is recommended to support decision making in this specialist field of clinical medicine. 相似文献
Reflex epilepsies have been demonstrated to exploit specific networks that subserve normal physiological function. It is unclear whether more common forms of epilepsy share this particular feature. By measuring interictal spikes in patients with a range of epilepsies, we show that 2 tasks known to specifically engage the hippocampus and temporal neocortex promoted increased interictal spiking within these regions, whereas a nonhippocampal dependent task did not. This indicates that interictal spike frequency may reflect the processing demands being placed on specific functional–anatomical networks in epilepsy. ANN NEUROL 2019;86:304–309 相似文献
Dermatofibrosarcoma protuberans with fibrosarcomatous transformation (DFSP-FS) is a higher grade tumor arising from dermatofibrosarcoma protuberans (DFSP). Recent literature highlights its impact on recurrence rates, metastatic rates, and survival. In this article, we aim to describe our experience with 13 cases of DFSP-FS in terms of pathologic findings, molecular alterations, clinical outcomes, management, and also perform a short recent literature review. 相似文献
Discrimination and internalized stigma are barriers to engagement in HIV self-care among men who have sex with men (MSM) living with HIV. However, differences in perceptions of discrimination and internalized stigmas by age, year of HIV-diagnosis, and race are poorly understood. We assessed differences in reported discrimination related to HIV, race, sexual orientation, and substance use and internalized stigmas among 202 MSM living with HIV who use substances. Younger participants reported higher levels of all types of discrimination and internalized stigmas (p-values < 0.001–0.030). Those diagnosed after the advent of antiretrovirals reported higher levels of discrimination related to HIV, sexual orientation, and substance use, as well as internalized stigma related to HIV and substance use (p-values 0.001–0.049). We explored perceived community HIV stigma, which accounted for associations involving age and year of diagnosis. Age, year of diagnosis, and race should be considered when assessing and intervening with stigma.