A Yeast Chemical Genetic Screen Identifies Inhibitors of Human Telomerase

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Highlights? Growth arrest induced by human telomerase in yeast is chemically reversible ? Readout is sensitive to telomerase catalytic activity and telomere recruitment ? Three cell-permeable compounds also inhibit purified human telomerase ? Yeast can be successfully used to screen for human telomerase inhibitors     

Substrate Envelope-Designed Potent HIV-1 Protease Inhibitors to Avoid Drug Resistance

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Biochemical and Structural Studies of Conserved Maf Proteins Revealed Nucleotide Pyrophosphatases with a Preference for Modified Nucleotides

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TDAG51 deficiency promotes oxidative stress-induced apoptosis through the generation of reactive oxygen species in mouse embryonic fibroblasts

Apoptosis has an important role in maintaining tissue homeostasis in cellular stress responses such as inflammation, endoplasmic reticulum stress, and oxidative stress. T-cell death-associated gene 51 (TDAG51) is a member of the pleckstrin homology-like domain family and was first identified as a pro-apoptotic gene in T-cell receptor-mediated cell death. However, its pro-apoptotic function remains controversial. In this study, we investigated the role of TDAG51 in oxidative stress-induced apoptotic cell death in mouse embryonic fibroblasts (MEFs). TDAG51 expression was highly increased by oxidative stress responses. In response to oxidative stress, the production of intracellular reactive oxygen species was significantly enhanced in TDAG51-deficient MEFs, resulting in the activation of caspase-3. Thus, TDAG51 deficiency promotes apoptotic cell death in MEFs, and these results indicate that TDAG51 has a protective role in oxidative stress-induced cell death in MEFs.     

Evaluating a four-directional benzene-centered aliphatic polyamine curing agent for epoxy resins

A four-directional benzene-centered aliphatic polyamine, MXBDP, with high functionality and low volatility, is used to cure epoxy resin (DGEBA). Herein we originally report the isothermal cure kinetics and dynamic mechanical properties of DGEBA/MXBDP. Differential scanning calorimetry confirms that MXDBP is more reactive than commercial linear metaxylenediamine and branched Jeffamine T-403 and the isothermal curing reaction is autocatalytic. The Kamal model is found to be able to well describe the curing rate up to the onset of diffusion control, and the excellent match over the whole conversion range is achieved using the extended Kamal model. Interestingly, the isoconversional kinetic analysis indicates that the effective reaction activation energy (E _α ) changes substantially with conversion, and ultimately decreases to a very small value (<10 kJ mol^?1) because of the diffusion-controlled reaction kinetics. Then, dynamic mechanical analysis reveals that DGEBA/MXBDP exhibits the higher α- and β-relaxation temperatures and the much higher crosslink density than DGEBA/metaxylenediamine. Our experiment results support that MXBDP has the high reactivity and improved thermal resistance in combination with the advantages of the high functionality, low volatility and decreased CO₂ absorption. Therefore, MXBDP may be especially suitable for room temperature-cure epoxy coatings and adhesives.     

Highly sensitive lable-free electrochemical aptasensor for thrombin detection with cobalt hexacyanoferrate as the electrochemical probe

A highly sensitive label-free electrochemical aptasensor has been constructed for the electrochemical detection of thrombin (TB), where two layers of cobalt hexacyanoferrate (CoHCF) redox probes sandwiched with carbon nanotubes–Nafion were directly immobilized on the electrode surface by electrodeposition. Through the strong interaction between CN^? (CoHCF) and gold nanoparticles (GNPs), GNPs were assembled on the CoHCF-modified electrode for the immobilization of thiolated thrombin aptamers (TBA). In the presence of target TB, TBA on the electrode surface could catch TB to form TBA–TB complex, which made a barrier for the electron transfer, resulting in a greater decrease in CoHCF redox probe signals. Thus, the proposed aptasensor showed a high sensitivity and a much wider linearity to TB in the range of 1.0 pg/mL?～?1.0 μg/mL with a detection limit of 0.28 pg/mL.