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1.
Phys Rev Lett ; 129(6): 061301, 2022 Aug 05.
Article in English | MEDLINE | ID: mdl-36018664

ABSTRACT

We report the first detection of the dark matter distribution around Lyman break galaxies (LBGs) at high redshift through the cosmic microwave background (CMB) lensing measurements with the public Planck PR3 κ map. The LBG sample consists of 1 473 106 objects with the median redshift of z∼4 that are identified in a total area of 305 deg^{2} observed by the Hyper Suprime-Cam Strategic Survey Program survey. After careful investigations of systematic uncertainties, such as contamination from foreground galaxies and cosmic infrared background, we obtain the significant detection of the CMB lensing signal at 5.1σ that is dominated by 2-halo term signals of the LBGs. Fitting a simple model consisting of the Navarro-Frenk-White profile and the linear-bias model, we obtain the typical halo mass of M_{h}=2.9_{-2.5}^{+9.5}×10^{11} h^{-1} M_{⊙}. Combining the CMB lensing and galaxy-galaxy clustering signals on the large scales, we demonstrate the first cosmological analysis at z∼4 that constrains (Ω_{m0},σ_{8}). We find that our constraint on σ_{8} is roughly consistent with the Planck cosmology, while this σ_{8} constraint is lower than the Planck cosmology over the 1σ level. This study opens up a new window for constraining cosmological parameters at high redshift by the combination of CMB and high-z galaxies, as well as studying the interplay between galaxy evolution and large-scale structure at such high redshift, by upcoming CMB and optical and near-infrared imaging surveys.

2.
Int J Biol Macromol ; 139: 75-84, 2019 Oct 15.
Article in English | MEDLINE | ID: mdl-31369782

ABSTRACT

Resorcinarenes are macrocyclic molecules that can bind different molecules in a supramolecular fashion. There are some sulfonated water-soluble derivatives that have been investigated to bind proteins avoiding fibrillation. The interaction with enzymes such as catalase (CAT) allows the interpretation of the possible effects of the use of resorcinarenes on human health or environmental applications. The interaction of five sulfonated resorcinarenes with different chemical structures was investigated by using different biophysical methods. The results of the spectroscopic experiments (fluorescence, synchronous fluorescence, and Uv-vis spectrophotometry) show different degrees of structural change, indicating that the binding of the macrocycles that were studied causes alterations on the conformation of CAT. The resorcinarenes reduce the activity of CAT in different extent, two macrocycles (named Na4EtRA and Na4PrRA, according to ethyl or propyl moieties at the lower pendant group) exhibit significant inhibition capacity (until ca. 70%). The study about inhibition types reveals a non-competitive mechanism for all the studied resorcinarenes. The docking calculations reveal that the macrocycles bond mainly to two domains of the CAT structure, which are not related with the active site.


Subject(s)
Calixarenes/chemistry , Calixarenes/metabolism , Catalase/metabolism , Liver/enzymology , Phenylalanine/analogs & derivatives , Sulfonic Acids/chemistry , Water/chemistry , Animals , Calixarenes/pharmacology , Catalase/chemistry , Cattle , Molecular Docking Simulation , Phenylalanine/chemistry , Phenylalanine/metabolism , Phenylalanine/pharmacology , Protein Binding , Protein Conformation , Solubility
3.
Chem Sci ; 8(3): 2003-2009, 2017 Mar 01.
Article in English | MEDLINE | ID: mdl-28451317

ABSTRACT

Amyloid-ß peptides (Aß) fibrillation is the hallmark of Alzheimer's disease (AD). However, it has been challenging to discover potent agents in order to inhibit Aß fibrillation. Herein, we demonstrated the effect of resorcinarene on inhibiting Aß fibrillation in vitro via experimental and computational methods. Aß were incubated with different concentrations of resorcinarene so as to monitor the kinetics by using thioflavin T binding assay. The results, which were further confirmed by far-UV CD spectroscopy and atomic force microscopy, strongly indicated that the higher concentration of resorcinarene, the more effective the inhibition of Aß fibrillation. A cytotoxicity study showed that when sea urchin embryos were exposed to the resorcinarene, the majority survived due to the resorcinarene low toxicity. In addition, when the resorcinarene was added, the formation of toxic Aß 42 species was delayed. Computational studies of Aß fibrillation, including docking simulations and MD simulations, illustrated that the interaction between inhibitor resorcinarene and Aß is driven by the non-polar interactions. These studies display a novel strategy for the exploration of promising antiamyloiddogenic agents for AD treatments.

4.
Langmuir ; 31(4): 1368-75, 2015 Feb 03.
Article in English | MEDLINE | ID: mdl-25588110

ABSTRACT

The host-guest properties of acetylated aryl pyrogallol[4]arene (AcPy) were studied as a Langmuir monolayer at the air-water interface. The self-assembled Langmuir monolayer properties and interactions with monovalent and divalent metal cations were investigated using surface pressure- and surface potential-area isotherms, compression-decompression cycles, stability, and infrared reflection-absorption spectroscopy (IRRAS). A favorable interaction is observed for complexation between acetylated aryl pyrogallol[4]arene with divalent calcium and cadmium cations, while no interaction is observed for monovalent sodium and potassium cations. Spectroscopic techniques allow for discrimination between cadmium and calcium complexation.

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