6 research outputs found
Biosensors in Biomedical Research: Development and Applications of Gene Chips
Nucleic-acid hybridisation techniques are a central tool for the genetic analysis of biological systems. Gene chips are complex arrays of recombinant plasmids or oligonucleotides immobilised on a glass chip of only 1 cm2. This technology allows, for the first time, the multiparallel expression-analysis of thousands of genes. Gene chips will be indispensable tools for the upcoming analysis of the human genome, once the entire sequence is known
Are the halogenations of simple enols in aqueous solution really diffusion-controlled reactions?
Analysis of Current DNA Encoded Library Screening Data Indicates Higher False Negative Rates for Numerically Larger Libraries
To optimize future
DNA-encoded library design, we have attempted
to quantify the library size at which the signal becomes undetectable.
To accomplish this we (i) have calculated that percent yields of individual
library members following a screen range from 0.002 to 1%, (ii) extrapolated
that ∼1 million copies per library member are required at the
outset of a screen, and (iii) from this extrapolation predict that
false negative rates will begin to outweigh the benefit of increased
diversity at library sizes >10<sup>8</sup>. The above analysis
is
based upon a large internal data set comprising multiple screens,
targets, and libraries; we also augmented our internal data with all
currently available literature data. In theory, high false negative
rates may be overcome by employing larger amounts of library; however,
we argue that using more than currently reported amounts of library
(≫10 nmoles) is impractical. The above conclusions may be generally
applicable to other DNA encoded library platforms, particularly those
platforms that do not allow for library amplification
DNA-Encoded Library-Derived DDR1 Inhibitor Prevents Fibrosis and Renal Function Loss in a Genetic Mouse Model of Alport Syndrome
The importance of Discoidin Domain Receptor 1 (DDR1) in renal fibrosis has been shown via gene knockout and use of antisense oligonucleotides; however, these techniques act via a reduction of DDR1 protein, while we prove the therapeutic potential of inhibiting DDR1 phosphorylation with a small molecule. To date, efforts to generate a selective small-molecule to specifically modulate the activity of DDR1 in an in vivo model have been unsuccessful. We performed parallel DNA encoded library screens against DDR1 and DDR2, and discovered a chemical series that is highly selective for DDR1 over DDR2. Structure-guided optimization efforts yielded the potent DDR1 inhibitor 2.45, which possesses excellent kinome selectivity (including 64-fold selectivity over DDR2 in a biochemical assay), a clean in vitro safety profile, and favorable pharmacokinetic and physicochemical properties. As desired, compound 2.45 modulates DDR1 phosphorylation in vitro as well as prevents collagen-induced activation of renal epithelial cells expressing DDR1. Compound 2.45 preserves renal function and reduces tissue damage in Col4a3-/- mice (the preclinical mouse model of Alport syndrome) when employing a therapeutic dosing regime, indicating the real therapeutic value of selectively inhibiting DDR1 phosphorylation in vivo. Our results may have wider significance as Col4a3-/- mice also represent a model for chronic kidney disease, a disease which affects 10% of the global population
DNA-Encoded Library-Derived DDR1 Inhibitor Prevents Fibrosis and Renal Function Loss in a Genetic Mouse Model of Alport Syndrome
β‑Secretase (BACE1) Inhibitors with High in Vivo Efficacy Suitable for Clinical Evaluation in Alzheimer’s Disease
An
extensive fluorine scan of 1,3-oxazines revealed the power of
fluorine(s) to lower the p<i>K</i><sub>a</sub> and thereby
dramatically change the pharmacological profile of this class of BACE1
inhibitors. The CF<sub>3</sub> substituted oxazine <b>89</b>, a potent and highly brain penetrant BACE1 inhibitor, was able to
reduce significantly CSF Aβ40 and 42 in rats at oral doses as
low as 1 mg/kg. The effect was long lasting, showing a significant
reduction of Aβ40 and 42 even after 24 h. In contrast to <b>89</b>, compound <b>1b</b> lacking the CF<sub>3</sub> group
was virtually inactive in vivo