University of Kentucky

About: University of Kentucky is a education organization based out in Lexington, Kentucky, United States. It is known for research contribution in the topics: Population & Poison control. The organization has 43933 authors who have published 92195 publications receiving 3256087 citations. The organization is also known as: UK.

Estradiol Modulates bcl-2 in Cerebral Ischemia: A Potential Role for Estrogen Receptors

Abstract: We have shown that physiological levels of estradiol exert profound protective effects on the cerebral cortex in ischemia induced by permanent middle cerebral artery occlusion. The major goal of this study was to begin to elucidate potential mechanisms of estradiol action in injury. Bcl-2 is a proto-oncogene that promotes cell survival in a variety of tissues including the brain. Because estradiol is known to promote cell survival via Bcl-2 in non-neural tissues, we tested the hypothesis that estradiol decreases cell death by influencing bcl-2 expression in ischemic brain injury. Furthermore, because estradiol may protect the brain through estrogen receptor-mediated mechanisms, we examined expression of both receptor subtypes ERα and ERβ in the normal and injured brain. We analyzed gene expression by RT-PCR in microdissected regions of the cerebral cortex obtained from injured and sham female rats treated with estradiol or oil. We found that estradiol prevented the injury-induced downregulation of bcl-2 expression. This effect was specific to bcl-2 , as expression of other members of the bcl-2 family ( bax, bcl-x L , bcl-x S, and bad ) was unaffected by estradiol treatment. We also found that estrogen receptors were differentially modulated in injury, with ERβ expression paralleling bcl-2 expression. Finally, we provide the first evidence of functional ERβ protein that is capable of binding ligand within the region of the cortex where estradiol-mediated neuroprotection was observed in cerebral ischemia. These findings indicate that estradiol modulates the expression of bcl-2 in ischemic injury. Furthermore, our data suggest that estrogen receptors may be involved in hormone-mediated neuroprotection.

Unnatural Selection: Perverse Incentives and the Misallocation of Credit in Japan

Abstract: We examine the misallocation of credit in Japan associated with the perverse incentives faced by banks to provide additional credit to the weakest firms. Firms are more likely to receive additional bank credit if they arein poor financial condition, because troubled Japanese banks have an incentive to allocate credit to severely impaired borrowers in order to avoid the realization of losses on their own balance sheets. This "evergreening" behavior is more prevalent among banks that have reported capital ratios close to the required minimum, and is compounded by the incentives arising from extensive corporate affiliations.

Engineering of human brain organoids with a functional vascular-like system

Abstract: Human cortical organoids (hCOs), derived from human embryonic stem cells (hESCs), provide a platform to study human brain development and diseases in complex three-dimensional tissue. However, current hCOs lack microvasculature, resulting in limited oxygen and nutrient delivery to the inner-most parts of hCOs. We engineered hESCs to ectopically express human ETS variant 2 (ETV2). ETV2-expressing cells in hCOs contributed to forming a complex vascular-like network in hCOs. Importantly, the presence of vasculature-like structures resulted in enhanced functional maturation of organoids. We found that vascularized hCOs (vhCOs) acquired several blood-brain barrier characteristics, including an increase in the expression of tight junctions, nutrient transporters and trans-endothelial electrical resistance. Finally, ETV2-induced endothelium supported the formation of perfused blood vessels in vivo. These vhCOs form vasculature-like structures that resemble the vasculature in early prenatal brain, and they present a robust model to study brain disease in vitro.

Psychopathy and the Five-factor model of personality: a replication and extension.

Abstract: It has recently been argued that psychopathy can be understood and represented using common dimensions of personality taken from the Five-factor model (FFM). In this research, we examined this possibility by using the Revised NEO Personality Inventory (NEO-PI-R; Costa & McCrae, 1992) to assess psychopathy in an undergraduate sample. Specifically, we matched individuals' NEO-PI-R profiles with an expert-generated psychopathy prototype to yield a psychopathy score. These scores were correlated with self-reports of drug use, delinquency, risky sex, aggression, and several laboratory tasks. FFM psychopathy was significantly related to all forms of deviance, although the effects tended to be small in size. Moreover, individuals who more closely resembled the prototypic FFM psychopath were more aggressive in a laboratory aggression task, less willing to delay gratification in a time discounting task, and demonstrated a preference for aggressive responses in a social information-processing paradigm.

The interaction between impulsivity and neighborhood context on offending: The effects of impulsivity are stronger in poorer neighborhoods

Abstract: This research blends 2 traditions of theorizing on the causes of crime, one focused on the role of individual differences and the other focused on structural and contextual variables. Two related studies examined the relations among impulsivity, neighborhood context, and juvenile offending. The first, cross-sectional study uses a large sample of 13-year-old inner-city boys, whereas the second, longitudinal study offers a conceptual replication using 17-year-old inner-city boys who are a subset of the original sample. Across both studies, results indicate that the effects of impulsivity on juvenile offending are stronger in poorer neighborhoods. Furthermore, nonimpulsive boys in poor neighborhoods were at no greater risk for delinquency than nonimpulsive boys in better-off neighborhoods.