1,206 research outputs found

    Curcumin/Melatonin Hybrids as Neuroprotective Agents for Alzheimer\u27s disease

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    Alzheimer\u27s disease (AD) is a progressive neurodegenerative disorder and the leading cause of dementia, affecting ~5.2 million Americans. Current FDA approved medications provide mainly symptomatic relief and there are no agents available to delay or cure this disease. Multiple factors such as amyloid-β aggregates, dyshomeostasis of biometals, oxidative stress, and neuroinflammation have been implicated in the development of AD. Even though significant advances have been made in understanding the mechanisms leading to AD, the exact etiology still remains elusive. Given AD’s multifactorial nature, a multifunctional strategy of small molecule design would help to identify novel chemical templates. Recently our lab has developed hybrid molecules of curcumin and melatonin that exhibited potent neuroprotective ability in various AD models. Further modifications identified a lead compound with potent neuroprotective and antioxidative activity in MC65 cells, while also establishing the hybrid strategy as a viable approach in providing unique chemotypes with novel pharmacology. Further preliminary biological studies suggest that the lead is orally available and exhibits multifunctional properties both in vitro and in vivo on AD pathologies, thus strongly encouraging further structural examination. Herein, we report the structural exploration of this chemical template through structure-activity relationship studies at three domains: the phenyl domain, α,β-unsaturated β-ketone amide domain, and the indole domain. Collectively, the results show that the chemical space around the curcumin portion doesn’t favor electronic or steric/hydrophobic interactions, but might favor pi-pi (π-π) and hydrogen-bond interactions. Additionally, the α,β-unsaturated β-ketone amide domain is not as important as the linearity of the β-ketone acetamide. Moreover, the results indicate that a free rotatable β-OH might be the actual moiety that is important for the observed biological activity through favorable hydrogen bonds. Finally, steric interactions are not favored in the chemical space surrounding the indole nitrogen, suggesting that hydrogen bond interactions are required for the observed neuroprotective activity. Conversely, a hydrogen bond acceptor is necessary at the 5-position of the indole ring and bulky substitutions can be accommodated, with restrictions, suggesting steric tolerance and hydrophobic interactions at this position. These modifications have yielded a series of novel compounds that are capable of modifying AD pathology while shedding further light onto the chemical scaffold thus warranting future investigations into the development, optimization, and characterization of these curcumin/melatonin hybrids as potential treatments for AD

    Suicide Terrorism: Performance Violence as Public Plunge

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    This article explores the relationship between the social psychology of the individual and the final abyss of suicide terrorism. The boy on the high dive is a metaphor for the fearful pause before the leap. For a young child, the dive is exciting and dangerous: the fearful pause is somewhat analogous to thoughts and feelings before the terrorist’s catastrophically destructive contemplated homicidal/suicidal behavior. If we think about the leap itself, there may be a better analogy. Is there any corollary to a specific group of suicide completers? What can be learned from others who have contemplated and undertaken perhaps the most public type of suicide—plunging from an extreme height? To what degree are those individuals fully committed compared with ambivalent? For those who are ambivalent and turn back, what is it that dissuades them? For those who appear committed and fail in their attempt, what is the likelihood of their returning again? Because suicidal jumping and suicide terrorism are both public acts, do these two groups on the pathway to fatal performance violence share similar motivations and ambivalence? If there are similarities among those who act publicly in fatal ways, are there policy-related means or measures that have been successful in decreasing public suicide that might also be applicable for decreasing the incidence of suicide terrorism? Through an examination of the content and process of public suicide, this article focuses on those individuals whose behavior is essential to the actual terrorist violence, especially if that behavior results in expected death to the individual. Not all persons engaged in terrorist activities will engage in a final fatal personal drama. Even in situations where lone actors conceive and execute terrorist actions, research has shown that there are bystanders who may have some preliminary knowledge of the event long before the audience to terroristic performance violence will witness the destructive event

    The Effect of Zinc Plating on Torque Coefficient

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    Short Summary of the EFCA Symposium on Ultrafine Particles - Brussels May 15th - 16th, 2019

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