The sphingosine-1-phosphate 1 receptor (S1P ) is expressed by lymphocytes, dendritic cells, and vascular endothelial cells and plays a role in the regulation of chronic inflammation and lymphocyte egress from peripheral lymphoid organs. Ozanimod is an oral selective modulator of S1P and S1P receptors in clinical development for the treatment of chronic immune-mediated, inflammatory diseases. This first-in-human study characterized the safety, pharmacokinetics (PK), and pharmacodynamics (PD) of ozanimod in 88 healthy volunteers using a range of single and multiple doses (7 and 28 days) and a dose-escalation regimen.
View Article and Find Full Text PDFBackground: When a physician-directed antibiotic-loaded polymethylmethacrylate (PMMA) bone cement (ALBC) formulation is used in total hip arthroplasties (THAs) and total knee arthroplasties (TKAs), current practice in the United States involves arbitrary choice of the antibiotic loading (herein defined as the ratio of the mass of the antibiotic added to the mass of the cement powder). We suggest there is a need to develop a rational method for determining this loading.
Questions/purposes: We propose a new method for determining the antibiotic loading to use when preparing a physician-directed ALBC formulation and illustrate this method using three in vitro properties of an ALBC in which the antibiotic was daptomycin.
Nucleosides Nucleotides Nucleic Acids
March 2006
Nucleoside reverse transcriptase inhibitors (NRTIs) are prodrugs which require three intracellular phosphorylation steps to yield their corresponding, biologically active, nucleoside triphosphate. In order to circumvent this often inefficient phosphorylation cascade, a plausible approach is to provide the active species directly in the form of a stabilized nucleoside triphosphate mimic. We have previously shown that such a mimic, namely 5'-alpha-Rp-borano-beta,gamma-(difluoromethylene)triphosphate (5'-alphaBCF2TP) is a generic triphosphate mimic that is biologically stable and can render antiviral ddNs with potent inhibitory activity against HIV-1 RT.
View Article and Find Full Text PDF3'-Azido-3',5-dideoxythymidine 5'-phosphonate and 3',5'-dideoxy-5'-difluoromethylenethymidine 5'-phosphonate were prepared by multistep syntheses. The nucleoside 5'-phosphonates were converted to their triphosphates and triphosphate mimics (P3Ms) containing beta,gamma-difluoromethylene, beta,gamma-dichloromethylene, or beta,gamma-imodo by condensation with pyrophosphate or pyrophosphate mimics, respectively. Inhibition of HIV-1 reverse transcriptase by the nucleoside P3Ms is briefly discussed.
View Article and Find Full Text PDFThe triphosphates of antiviral 2',3'-dideoxynucleosides (ddNs) are the active chemical species that inhibit viral DNA synthesis. The inhibition involves incorporation of ddNMP into DNA and subsequent chain termination. A conceivable strategy for antiviral drugs is to employ nucleoside 5'-triphosphate mimics that can entirely bypass cellular phosphorylation.
View Article and Find Full Text PDFIn search of active nucleoside 5'-triphosphate mimics, we have synthesized a series of AZT triphosphate mimics (AZT P3Ms) and evaluated their inhibitory effects on HIV-1 reverse transcriptase as well as their stability in fetal calf serum and in CEM cell extracts. Reaction of AZT with 2-chloro-4H-1,3,2-benzodioxaphosphorin-4-one, followed by treatment of the phosphite intermediate 2 with pyrophosphate analogues, yielded the cyclic triphosphate intermediates 4b-4f, which were subjected to boronation and subsequent hydrolysis to give AZT 5'-alpha-borano-beta,gamma-bridge-modified triphosphates 6b-6f in moderate to good yields. Reaction of the cyclic intermediate 4d with iodine, followed by treatment with a series of nucleophiles, afforded the AZT 5'-beta,gamma-difluoromethylene-gamma-substituted triphosphates (7b-7i).
View Article and Find Full Text PDFNucleosides Nucleotides Nucleic Acids
October 2004
IMPDH inhibitors have potential antimicrobial, anticancer and immunomodulatory effects. Nucleoside inhibitors of IMPDH exert their inhibitory effects via nucleoside 5'-MPs. Conversion of nucleoside analogs to NMPs by cellular nucleoside kinases is not assured, and usually is inefficient.
View Article and Find Full Text PDFEven prior to passage of federal welfare reform, many demonstration programs anticipated key features of the 1996 law, such as "work-first" strategies, time limits on welfare receipt, and financial incentives to work. Over the past decade, 10 experimental evaluations of these programs have extended their studies to examine the impacts on children. This article provides a synthesis of findings from the first seven of these studies to release results concerning child impacts.
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