21 research outputs found
Comparing Direct Factor Xa Inhibitors and Warfarin in the Prevention of Stroke in Patients with Atrial Fibrillation
Objective: To evaluate the overall efficacy, advantages, and disadvantages of treatment with direct factor Xa inhibitors as compared to warfarin in the prevention of stroke in patients with atrial fibrillation. Methods: A quantitative meta-analysis was performed on three separate studies, each of which evaluated the efficacy and safety outcomes of a direct factor Xa inhibitor versus warfarin in preventing stroke in patients with atrial fibrillation. The direct factor Xa inhibitors that were evaluated included apixaban, edoxaban, and rivaroxaban. Results: The direct factor Xa inhibitors were found to be as effective, and in some cases more effective, than warfarin in preventing stroke in patients with atrial fibrillation. In addition, the direct factor Xa inhibitors were associated with a significantly decreased rate of major bleeding events, as compared to warfarin
Flavocoxid Inhibits Phospholipase A2, Peroxidase Moieties of the Cyclooxygenases (COX), and 5-Lipoxygenase, Modifies COX-2 Gene Expression, and Acts as an Antioxidant
The multiple mechanisms of action for flavocoxid relating to arachidonic acid (AA) formation and metabolism were studied in vitro. Flavocoxid titrated into rat peritoneal macrophage cultures inhibited cellular phospholipase A2 (PLA2) (IC50 = 60 μg/mL). In in vitro enzyme assays, flavocoxid showed little anti-cyclooxygenase (CO) activity on COX-1/-2 enzymes, but inhibited the COX-1 (IC50 = 12.3) and COX-2 (IC50 = 11.3 μg/mL) peroxidase (PO) moieties as well as 5-lipoxygenase (5-LOX) (IC50 = 110 μg/mL). No detectable 5-LOX inhibition was found for multiple traditional and COX-2 selective NSAIDs. Flavocoxid also exhibited strong and varied antioxidant capacities in vitro and decreased nitrite levels (IC50 = 38 μg/mL) in rat peritoneal macrophages. Finally, in contrast to celecoxib and ibuprofen, which upregulated the cox-2 gene, flavocoxid strongly decreased expression. This work suggests that clinically favourable effects of flavocoxid for management of osteoarthritis (OA) are achieved by simultaneous modification of multiple molecular pathways relating to AA metabolism, oxidative induction of inflammation, and neutralization of reactive oxygen species (ROS)
Preparation and frst biological evaluation of novel Re-188/Tc-99m peptide conjugates with substance-P
Introduction: New 188Re and 99mTc peptide conjugates with substance- P (SP) were prepared and biologically evaluated. The radiopharmaceuticals have been labelled with the [M=N]2+ (M=99mTc, 188Re) core using a combination of pi-donor tridentate and pi-acceptor monodentate ancillary ligands.
Methods: The new radiopharmaceuticals have been prepared through a two-step reaction by simultaneous addition of the tridentate and monodentate ligands to a vial containing a preformed [M=N]2+ core. The tridentate ligand was formed by linking two cysteine residues to the terminal arginine of the undecapeptide SP, whereas the monodentate ligand was a tertiary phosphine. The preparation of the corresponding Re-188 derivative required developing a more complex chemical procedure to obtain the [Re=N]2+ core in satisfactory yields. Characterization of the resulting products was obtained by chromatographic methods. Biological evaluation was performed for both Tc-99m and Re-188 derivatives by in-vitro studies on isolated cells expressing NK1-receptors. In-vivo imaging in mice was carried out using a small-animal YAP(S)PET tomograph.
Conclusion: New Tc-99m and Re-188 peptide radiopharmaceuticals with SP have been prepared in high yield and with high-specifc activity. Both Tc-99m and Re-188 peptide radioconjugates exhibit high
affnity for NK1 receptors, thus giving further evidence to the empirical rule that structurally related Tc-99m and Re-188 radiopharmaceuticals exhibit identical biological properties
CPEB2, CPEB3 and CPEB4 are coordinately regulated by miRNAs recognizing conserved binding sites in paralog positions of their 3′-UTRs
The cytoplasmic polyadenylation element binding-protein (CPEB) is an RNA-binding protein that participates in translational control. CPEB2, CPEB3 and CPEB4 are paralog proteins very similar among themselves referred as the CPEB2 subfamily. To gain insight into common mechanisms of regulation of the CPEB2 subfamily transcripts, we looked for putative cis-acting elements present in the 3′-UTRs of the three paralogs. We found different families of miRNAs predicted to target all subfamily members. Most predicted target sites for these families are located in paralog positions suggesting that these putative regulatory motifs were already present in the ancestral gene. We validated target sites for miR-92 and miR-26 in the three paralogs using mutagenesis of miRNA-binding sites in reporter constructs combined with over-expression and depletion of miRNAs. Both miR-92 and miR-26 induced a decrease in Luciferase activity associated to a reduction in mRNA levels of the reporter constructs. We also showed that the endogenous miRNAs co-regulate CPEB2, CPEB3 and CPEB4 transcripts, supporting our hypothesis that these genes have a common regulatory mechanism mediated by miRNAs. We also suggest that the ancestral pattern of miRNA-binding motifs was maintained throughout the generation of highly conserved elements in each of the 3′-UTRs
The JWST Galactic Center Survey -- A White Paper
The inner hundred parsecs of the Milky Way hosts the nearest supermassive
black hole, largest reservoir of dense gas, greatest stellar density, hundreds
of massive main and post main sequence stars, and the highest volume density of
supernovae in the Galaxy. As the nearest environment in which it is possible to
simultaneously observe many of the extreme processes shaping the Universe, it
is one of the most well-studied regions in astrophysics. Due to its proximity,
we can study the center of our Galaxy on scales down to a few hundred AU, a
hundred times better than in similar Local Group galaxies and thousands of
times better than in the nearest active galaxies. The Galactic Center (GC) is
therefore of outstanding astrophysical interest. However, in spite of intense
observational work over the past decades, there are still fundamental things
unknown about the GC. JWST has the unique capability to provide us with the
necessary, game-changing data. In this White Paper, we advocate for a JWST
NIRCam survey that aims at solving central questions, that we have identified
as a community: i) the 3D structure and kinematics of gas and stars; ii)
ancient star formation and its relation with the overall history of the Milky
Way, as well as recent star formation and its implications for the overall
energetics of our galaxy's nucleus; and iii) the (non-)universality of star
formation and the stellar initial mass function. We advocate for a large-area,
multi-epoch, multi-wavelength NIRCam survey of the inner 100\,pc of the Galaxy
in the form of a Treasury GO JWST Large Program that is open to the community.
We describe how this survey will derive the physical and kinematic properties
of ~10,000,000 stars, how this will solve the key unknowns and provide a
valuable resource for the community with long-lasting legacy value.Comment: This White Paper will be updated when required (e.g. new authors
joining, editing of content). Most recent update: 24 Oct 202