1,075 research outputs found
The influence of meridional ice transport on Europa’s ocean stratification and heat content
Jupiter’s moon Europa likely hosts a saltwater ocean beneath its icy surface. Geothermal heating and rotating convection in the ocean may drive a global overturning circulation that redistributes heat vertically and meridionally, preferentially warming the ice shell at the equator. Here we assess the previously unconstrained influence of ocean‐ice coupling on Europa’s ocean stratification and heat transport. We demonstrate that a relatively fresh layer can form at the ice‐ocean interface due to a meridional ice transport forced by the differential ice shell heating between the equator and the poles. We provide analytical and numerical solutions for the layer’s characteristics, highlighting their sensitivity to critical ocean parameters. For a weakly turbulent and highly saline ocean, a strong buoyancy gradient at the base of the freshwater layer can suppress vertical tracer exchange with the deeper ocean. As a result, the freshwater layer permits relatively warm deep ocean temperatures.Key PointsCoupling of Europa’s ocean circulation and the ice shell impacts global stratificationA low‐latitude freshwater layer may suppress vertical heat and tracer transportParameter space is explored based on properties observed by future missionsPeer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/137725/1/grl56051.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/137725/2/grl56051-sup-0001-TextS1.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/137725/3/grl56051_am.pd
The Interrelations Between Spiritual Well-Being, Pain Interference and Depressive Symptoms in Patients with Multiple Sclerosis
Depressive symptoms are common in individuals with multiple sclerosis (MS), and are frequently exacerbated by pain; however, spiritual well-being may allow persons with MS to more effectively cope with pain-related deficits in physical and role functioning. We explored the associations between spiritual well-being, pain interference and depressive symptoms, assessing each as a potential mediator, in eighty-one patients being treated for MS, who completed self-report measures: Functional Assessment of Chronic Illness Therapy-Spiritual Well-Being Scale, Pain Effects Scale, and Center for Epidemiologic Studies Depression Scale Revised. At the bivariate level, spiritual well-being and its subscale of meaning and peace were negatively associated with depression and pain interference. In mediation models, depression was not related to pain interference via spiritual well-being, or to spiritual well-being via pain interference. Pain interference was related to depression via spiritual well-being and meaning/peace, and to spiritual well-being and meaning/peace via depressive symptoms. Finally, spiritual well-being and meaning/peace were related to depression via pain interference, and to pain interference via depressive symptoms. For patients with MS, a multi-faceted approach to treatment that includes pain reduction and promotion of spiritual well-being may be beneficial, although amelioration of depression remains a critical task
A randomized trial of memantine as treatment for spasticity in multiple sclerosis
Abstract We report the results of a single center randomized, double-blind, placebo-controlled, parallel group trial of memantine in adults with multiple sclerosis and spasticity conducted over 12 weeks. Eligible MS patients had to have an Ashworth spasticity rating of 2 or higher in at least one lower extremity muscle group. Subjects were randomized to receive either placebo or memantine 10 mg twice a day. The primary outcome measure for efficacy was the change in Ashworth Spasticity Scale Score. Although well tolerated, memantine treatment did not demonstrate efficacy in treatment of spasticity in this 12-week small exploratory study
A randomized trial of memantine as treatment for spasticity in multiple sclerosis
Abstract We report the results of a single center randomized, double-blind, placebo-controlled, parallel group trial of memantine in adults with multiple sclerosis and spasticity conducted over 12 weeks. Eligible MS patients had to have an Ashworth spasticity rating of 2 or higher in at least one lower extremity muscle group. Subjects were randomized to receive either placebo or memantine 10 mg twice a day. The primary outcome measure for efficacy was the change in Ashworth Spasticity Scale Score. Although well tolerated, memantine treatment did not demonstrate efficacy in treatment of spasticity in this 12-week small exploratory study
Antimalarial activity of the anticancer histone deacetylase inhibitor SB939
Histone deacetylase (HDAC) enzymes posttranslationally modify lysines on histone and nonhistone proteins and play crucial roles in epigenetic regulation and other important cellular processes. HDAC inhibitors (e.g., suberoylanilide hydroxamic acid [SAHA; also known as vorinostat]) are used clinically to treat some cancers and are under investigation for use against many other diseases. Development of new HDAC inhibitors for noncancer indications has the potential to be accelerated by piggy-backing onto cancer studies, as several HDAC inhibitors have undergone or are undergoing clinical trials. One such compound, SB939, is a new orally active hydroxamate-based HDAC inhibitor with an improved pharmacokinetic profile compared to that of SAHA. In this study, the in vitro and in vivo antiplasmodial activities of SB939 were investigated. SB939 was found to be a potent inhibitor of the growth of Plasmodium falciparum asexual-stage parasites in vitro (50% inhibitory concentration [IC50], 100 to 200 nM), causing hyperacetylation of parasite histone and nonhistone proteins. In combination with the aspartic protease inhibitor lopinavir, SB939 displayed additive activity. SB939 also potently inhibited the in vitro growth of exoerythrocytic-stage Plasmodium parasites in liver cells (IC50, similar to 150 nM), suggesting that inhibitor targeting to multiple malaria parasite life cycle stages may be possible. In an experimental in vivo murine model of cerebral malaria, orally administered SB939 significantly inhibited P. berghei ANKA parasite growth, preventing development of cerebral malaria-like symptoms. These results identify SB939 as a potent new antimalarial HDAC inhibitor and underscore the potential of investigating next-generation anticancer HDAC inhibitors as prospective new drug leads for treatment of malaria
The influence of meridional ice transport on Europa's ocean stratification and heat content
Jupiter's moon Europa likely hosts a saltwater ocean beneath its icy surface. Geothermal heating and rotating convection in the ocean may drive a global overturning circulation that redistributes heat vertically and meridionally, preferentially warming the ice shell at the equator. Here we assess the previously unconstrained influence of ocean-ice coupling on Europa's ocean stratification and heat transport. We demonstrate that a relatively fresh layer can form at the ice-ocean interface due to a meridional ice transport forced by the differential ice shell heating between the equator and the poles. We provide analytical and numerical solutions for the layer's characteristics, highlighting their sensitivity to critical ocean parameters. For a weakly turbulent and highly saline ocean, a strong buoyancy gradient at the base of the freshwater layer can suppress vertical tracer exchange with the deeper ocean. As a result, the freshwater layer permits relatively warm deep ocean temperatures
Common Data Elements for Traumatic Brain Injury: Recommendations From the Biospecimens and Biomarkers Working Group
Recent advances in genomics, proteomics, and biotechnology have provided unprecedented opportunities for translational research and personalized medicine. Human biospecimens and biofluids represent an important resource from which molecular data can be generated to detect and classify injury and to identify molecular mechanisms and therapeutic targets. To date, there has been considerable variability in biospecimen and biofluid collection, storage, and processing in traumatic brain injury (TBI) studies. To realize the full potential of this important resource, standardization and adoption of best practice guidelines are required to insure the quality and consistency of these specimens. The aim of the Biospecimens and Biomarkers Working Group was to provide recommendations for core data elements for TBI research and develop best practice guidelines to standardize the quality and accessibility of these specimens. Consensus recommendations were developed through interactions with focus groups and input from stakeholders participating in the interagency workshop on Standardization of Data Collection in TBI and Psychological Health held in Washington, DC, in March 2009. With the adoption of these standards and best practices, future investigators will be able to obtain data across multiple studies with reduced costs and effort and accelerate the progress of genomic, proteomic, and metabolomic research in TBI
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