Phlorotannins as HIV Vpu inhibitors, an in silico virtual screening study of marine natural products.

The importance of new effective treatment methodologies for human immunodeficiency virus (HIV) is undeniable for the medical society. Viral protein U (Vpu), one of the disparaged accessory proteins of HIV, is responsible for the dissemination of viral particles, and HIV mutants lacking Vpu protein have remarkably reduced pathogenicity. Here, we explored the marine natural products to find the leading structures which can potentially inhibit the activity of Vpu in silico.

Hydroxyapatite as a biomaterial - a gift that keeps on giving.

The synthetic analogue to biogenic apatite, hydroxyapatite (HA) has a number of physicochemical properties that make it an attractive candidate for diagnosis, treatment of disease and augmentation of biological tissues. Here we describe some of the recent studies on HA, which may provide bases for a number of new medical applications. The content of this review is divided to different medical application modes utilizing HA, including tissue engineering, medical implants, controlled drug delivery, gene therapies, cancer therapies and bioimaging.

Nickel Ferrite (NiFe₂O₄) Nanoparticles as Magnetically Recyclable Nanocatalyst for Highly Efficient Synthesis of 4H-Chromene Derivatives.

An adapted one-pot route to nanocatalyst-assisted synthesis of 4H-chromenes via three component condensation reaction between dimedone, malononitrile, and a broad range of aryl aldehydes by the use of magnetic nickel ferrite nanoparticles is described. By this achievement, not only a novel route to highly efficient synthesis of these series of heterocycles was introduced but also the scope of these medicinally important products was developed via preparation of some novel products. Above all, a new application of nickel ferrite nanoparticles (NiFe₂O₄ NPs) as highly efficient, green and magnetically recyclable catalyst has been introduced.

Design, synthesis, biological evaluation, and molecular dynamics of novel cholinesterase inhibitors as anti-Alzheimer's agents.

A series of novel chroman-4-one derivatives were designed and synthesized successfully with good to excellent yield (3a-l). In addition, the obtained products were evaluated for their cholinesterase (ChE) inhibitory activities. The results show that among the various synthesized compounds, analogs bearing the piperidinyl ethoxy side chain with 4-hydroxybenzylidene on the 3-positions of chroman-4-one (3l) showed the most potent activity with respect to acetylcholinesterase (anti-AChE activity; IC  = 1.

Metronidazole aryloxy, carboxy and azole derivatives: Synthesis, anti-tumor activity, QSAR, molecular docking and dynamics studies.

A series of novel metronidazole aryloxy, carboxy and azole derivatives has been synthesized and their cytotoxic activities on three cancer cell lines were evaluated by MTT assay. Compounds 4m, 4l and 4d showed the most potent cytotoxic activity (ICs less than 100 µg/mL). Apoptosis was also detected for these compounds by flow cytometry.

The detour problem in a stochastic environment: Tolman revisited.

We designed a grid world task to study human planning and re-planning behavior in an unknown stochastic environment. In our grid world, participants were asked to travel from a random starting point to a random goal position while maximizing their reward. Because they were not familiar with the environment, they needed to learn its characteristics from experience to plan optimally.

Learning to allocate limited time to decisions with different expected outcomes.

The goal of this article is to investigate how human participants allocate their limited time to decisions with different properties. We report the results of two behavioral experiments. In each trial of the experiments, the participant must accumulate noisy information to make a decision.

Learning to maximize reward rate: a model based on semi-Markov decision processes.

WHEN ANIMALS HAVE TO MAKE A NUMBER OF DECISIONS DURING A LIMITED TIME INTERVAL, THEY FACE A FUNDAMENTAL PROBLEM: how much time they should spend on each decision in order to achieve the maximum possible total outcome. Deliberating more on one decision usually leads to more outcome but less time will remain for other decisions. In the framework of sequential sampling models, the question is how animals learn to set their decision threshold such that the total expected outcome achieved during a limited time is maximized.