Photoinduced Radical Approach for Desulfurative Alkylation of Cysteine Derivatives to Make Unnatural Amino Acids.

Unnatural amino acids (UAAs) are highly valuable molecules in organic synthesis, pharmaceutical sciences, and material science. Herein, we present a photocatalytic radical approach for desulfurative alkylation of cysteine derivatives with arenethiol as the hydrogen atom transfer catalyst for making UAAs and peptides. The formate salt, acting as the hydrogen atom donor, in situ generates the highly reductive CO radical anion species, which is the key to unlocking the C-S bond cleavage process with a simple benzoyl protecting group.

Complex effects of testosterone level on ectoparasite load in a ground squirrel: an experimental test for the immunocompetence handicap hypothesis.

Background: The immunocompetence handicap hypothesis suggests that males with a higher testosterone level should be better at developing male secondary traits, but at a cost of suppressed immune performance. As a result, we should expect that males with an increased testosterone level also possess a higher parasite load. However, previous empirical studies aimed to test this prediction have generated mixed results.

Effects of involuntary treadmill running in combination with swimming on adult neurogenesis in an Alzheimer's mouse model.

Physical exercise plays a role on the prevention and treatment of Alzheimer's disease (AD), but the exercise mode and the mechanism for these positive effects is still ambiguous. Here, we investigated the effect of an aerobic interval exercise, running in combination with swimming, on behavioral dysfunction and associated adult neurogenesis in a mouse model of AD. We demonstrate that 4 weeks of the exercise could ameliorate Aβ oligomer-induced cognitive impairment in mice utilizing Morris water maze tests.

Enhanced expression of microtubule-associated protein 7 functioned as a contributor to cervical cancer cell migration and is predictive of adverse prognosis.

Background: Cervical cancer (CC) is one of the most common female malignancies over the world. Microtubule-associated protein 7 (MAP7) belongs to the family of microtubule-associated proteins (MAPs) which involve in microtubule dynamics and are critical in several important cellular and intracellular activities. This study aimed to investigate the expression and potential role of MAP7 in CC.

Design, synthesis, and biological evaluations of phenylpropiolic acid derivatives as novel GPR40 agonists.

GPR40, also known as free fatty acid receptor 1 (FFAR1), is a member of G protein-coupled receptors (GPCR) family and has emerged as an attractive target for the treatment of type 2 diabetes mellitus. So far, most of the synthetic GPR40 agonists, including several drug candidates discontinued in clinical trials, were derived from the phenylpropionic acid scaffold. For discovering novel GPR40 agonists with diverse chemical structures, a series of phenylpropiolic acid derivatives were designed, synthesized, and evaluated under a battery of bioassays.

Effect of N-Perfluorooctane on Hypoxia/Reoxygenation Injury in Human Umbilical Vein Endothelial Cells.

Background: This study investigated the effect of n-perfluorooctane (PFC) on hypoxia/reoxygenation (H/R) injury in human umbilical vein endothelial cells (HUVECs).

Methods: In this study, the H/R models were prepared by chemical methods (using dithionite solution). The experimental groups included the control group, the PFC group with a culture volume ratio of 10%, the H/R model group, and treatment groups with various doses of PFC + H/R (i.

Effects of cattle grazing on small mammal communities in the Hulunber meadow steppe.

Small mammals play important roles in many ecosystems, and understanding their response to disturbances such as cattle grazing is fundamental for developing sustainable land use strategies. However, how small mammals respond to cattle grazing remains controversial. A potential cause is that most of previous studies adopt rather simple experimental designs based solely on the presence/absence of grazing, and are thus unable to detect any complex relationships between diversity and grazing intensity.

Electrophysiological and behavioral responses of Diaphania glauculalis males to female sex pheromone.

The aim of this study is to identify the pheromone active component of female moths, Diaphania glauculalis, an important pest of Anthocephalus chinensis in China. The sex pheromone was extracted from sex pheromone gland extracts of virgin female moth of D. glauculalis using n-hexane, and the pheromone gland extracts of females were analyzed using coupled gas chromatography-electroantennogram detection (GC-EAD) and gas chromatography-mass spectrometry (GC-MS).

[The first confirmed human case of avian influenza A (H5N1) in mainland, China].

Objective: To ascertain the causation of a family cluster involving two undefined pneumonia cases, a 12-year-old girl and her brother, reported October, 2005 in Xiangtan county, Hunan province.

Methods: Information on epidemiology and clinical manifestation of the cases was collected from interviewing the keyman and referring to related medical records. The environment exposure of the cases to their households and the timeline of the illness were reproduced, using this information.