The multiple merger assembly of a hyperluminous obscured quasar at redshift 4.6

Galaxy mergers and gas accretion from the cosmic web drove the growth of galaxies and their central black holes at early epochs. We report spectroscopic imaging of a multiple merger event in the most luminous known galaxy, WISE J224607.56-052634.9 (W2246-0526), a dust-obscured quasar at redshift 4.6, 1.3 billion years after the Big Bang. Far-infrared dust continuum observations show three galaxy companions around W2246-0526 with disturbed morphologies, connected by streams of dust likely produced by the dynamical interaction. The detection of tidal dusty bridges shows that W2246-0526 is accreting its neighbors, suggesting that merger activity may be a dominant mechanism through which the most luminous galaxies simultaneously obscure and feed their central supermassive black holes.

Author Correction: Nearly all the sky is covered by Lyman-α emission around high-redshift galaxies

Change history: In this Letter, author M. Akhlaghi should be associated with affiliation (2) rather than (3). This error has been corrected online.

Indirect micromanipulation of single molecules in water-in-oil emulsion

Based on real-time observation and micromanipulation, analytical methods for single DNA molecules have been under development for some time. Precise manipulation, however, is still difficult because single molecules are too small for conventional techniques. We have developed a chemical reaction system that uses water droplets in oil as containers of materials. The water droplets can be manipulated by optical force. The manipulation of the water droplets permits the fusion of two selected droplets. This process corresponds to mixing of different samples. We designate this system as "w/o (water-in-oil emulsion) microreactor system", and each droplet can be thought of as a "microreactor". In this system, single molecules can be manipulated readily, as a molecule can be contained in a microm-sized microreactor. The microreactor utilizes extremely small quantities of samples, therefore, reactions are rapid, as diffusion times in the microreactor are very short. The manipulation technique of the microreactors based on optical force has been applied to induce fusion between microreactors loaded with DNA and YOYO, a fluorescent dye that binds to DNA. This fusion induced a rapid binding of YOYO.

A novel class of inhibitors for human and rat steroid 5alpha-reductases: synthesis and biological evaluation of indoline and aniline derivatives. III

While searching for novel nonsteroidal inhibitors of human and rat prostatic 5alpha-reductases, we found a new series of indoline and aniline derivatives that showed potent inhibitory activities for both enzymes. Among them, 3-chloro-4-¿[1-(4-phenoxybenzyl)indolin-5-yl]oxylbenzoic acid (2e, YM-36117) showed a more potent inhibitory activity for the human enzyme than ONO-3805 with an IC50 value of 5.3 nM and a reduced rat prostatic dihydrotestosterone (DHT) concentration by oral administration. The synthesis and the structure-activity relationships of these indoline and aniline derivatives are presented.

A novel class of inhibitors for human steroid 5alpha-reductase: synthesis and biological evaluation of indole derivatives. II

In a search for novel nonsteroidal inhibitors of human prostatic 5alpha-reductase, we found a new series of indole derivatives that showed potent inhibitory activities for the human enzyme. Among them, 4-[(1-benzyl-1H-indol-5-yl)oxyl-3-chlorobenzoic acid (2d, YM-32906) showed more potent inhibitory activity than finasteride with an IC50 value of 0.44 nM. 3-Chloro-4-[[1-(4-phenoxybenzyl)-1H-indol-5-yl]oxy]benzoic acid (2m) showed inhibitory activities for both human and rat prostatic 5alpha-reductase with IC50 values of 2.1 and 73 nM, respectively. The synthesis and structure-activity relationships of these indole derivatives are presented.

In-vitro characterization of YM872, a selective, potent and highly water-soluble alpha-amino-3-hydroxy-5-methylisoxazole-4-propionate receptor antagonist

The in-vitro pharmacological properties of (2,3-dioxo-7-(1H-imidazol-1-yl)-6-nitro-1,2,3,4-tetrahydro-1-quinoxal inyl)-acetic acid monohydrate, YM872, a novel and highly water-soluble alpha-amino-3-hydroxy-5-methylisoxazole-4-propionate (AMPA)-receptor antagonist were investigated. YM872 is highly water soluble (83 mg mL(-1) in Britton-Robinson buffer) compared with 2,3-dihydroxy-6-nitro-7-sulphamoyl-benzo(F)quinoxaline (NBQX), 6-(1H-imidazol-1-yl)-7-nitro-2,3(1H,4H)-quinoxalinedione hydrochloride (YM90K) or 6-cyano-7-nitroquinoxaline-2,3-dione (CNQX). YM872 potently inhibits [3H]AMPA binding with a Ki (apparent equilibrium dissociation constant) value of 0.096 +/- 0.0024 microM. However, YM872 had very low affinity for other ionotropic glutamate receptors, as measured by competition with [3H]kainate (high-affinity kainate binding site, concentration resulting in half the maximum inhibition (IC50) = 4.6 +/- 0.14 microM), [3H]glutamate (N-methyl-D-aspartate (NMDA) receptor glutamate binding site, IC50 > 100 microM) and [3H]glycine (NMDA receptor glycine-binding site, IC50 > 100 microM). YM872 competitively antagonized kainate-induced currents in Xenopus laevis oocytes which express rat AMPA receptors, with a pA2 value of 6.97 +/- 0.01. In rat hippocampal primary cultures, YM872 blocked a 20-microM AMPA-induced increase of intracellular Ca2+ concentration with an IC50 value of 0.82 +/- 0.031 microM, and blocked 300-microM kainate-induced neurotoxicity with an IC50 value of 1.02 microM. These results show that YM872 is a potent and highly water-soluble AMPA antagonist with great potential for treatment of neurodegenerative disorders such as stroke.