Researchers in the post-genome era are confronted with the daunting task of assigning structure and function to tens of thousands of encoded proteins. To realize this goal, new technologies are emerging for the analysis of protein function on a global scale, such as activity-based protein profiling (ABPP), which aims to develop active site-directed chemical probes for enzyme analysis in whole proteomes. For the pursuit of such chemical proteomic technologies, it is helpful to derive inspiration from protein-reactive natural products. Natural products use a remarkably diverse set of mechanisms to covalently modify enzymes from distinct mechanistic classes, thus providing a wellspring of chemical concepts that can be exploited for the design of active-site-directed proteomic probes. Herein, we highlight several examples of protein-reactive natural products and illustrate how their mechanisms of action have influenced and continue to shape the progression of chemical proteomic technologies like ABPP.

http://www.scripps.edu/cravatt/pdf/Drahl2005.pdf

Protein-reactive natural products.

Composite materials formed by the combination of inorganic materials and organic polymers are attractive for the purpose of creating high-performance or high-functional polymeric materials. Of particular interest is the molecular level combination of two different components that may lead to new composite materials, termed ‘organic—inorganic hybrid materials’. Recently, new methods for preparing these hybrid materials have been reported. Some improvements of the properties or modifications of these materials have also been explored from the viewpoint of industrial applications.

Organic—inorganic hybrid materials

Natural products against Alzheimer's disease: Pharmaco-therapeutics and biotechnological interventions

Azetidine, pyrrole, pyrrolidine, piperidine, and pyridine alkaloids

In addition to their well-established self-renewal and multipotent differentiation properties, mesenchymal stem cells (MSCs) also possess potent immunomodulatory functions both in vitro and in vivo, which render them a potential novel immunotherapeutic tool for a variety of autoimmune and inflammation-related diseases. The major mechanisms may involve (1) the secretion of an array of soluble factors such as prostaglandin E2 (PGE2 ), indoleamine 2, 3-dioxygenase (IDO), transforming growth factor-β (TGF-β), and human leukocyte antigen G5 (HLA-G5); (2) interactions between MSCs and immune cells such as T cells, B cells, macrophages, and dendritic cells. Recently, increasing evidence has supported that MSCs derived from dental tissues are promising alternative sources of multipotent MSCs. We here provide a thorough and extensive review about new findings in the immunomodulatory functions of MSCs derived from several dental tissues, including dental pulp, periodontal ligament, gingiva, exfoliated deciduous teeth, apical papilla, and dental follicle, respectively. The immunomodulatory properties of dental MSCs place them as a more accessible cell source than bone marrow-derived MSCs for cell-based therapy of immune and inflammation-related diseases.

Immunomodulatory properties of dental tissue-derived mesenchymal stem cells

Purpose: The aim of this study was to investigate the immunomodulatory effects of canine periodontal ligament stem cells on allogenic and xenogenic immune cells in vitro. Methods: Mixed cell cultures consisting of canine stem cells (periodontal ligament stem cells and bone marrow stem cells) and allogenic canine/xenogenic human peripheral blood mononuclear cells (PBMCs) were established following the addition of phytohemagglutinin. The proliferation of PBMCs was evaluated using the MTS assay. The cell division of PBMCs was analyzed using the CFSE assay. The apoptosis of PBMCs was assessed using the trypan blue uptake method. Results: Periodontal ligament stem cells and bone marrow stem cells inhibited the proliferation of allogenic and xenogenic PBMCs. Both periodontal ligament stem cells and bone marrow stem cells suppressed the cell division of PBMCs despite the existence of a mitogen. No significant differences in the percentages of apoptotic PBMCs were found among the groups. Conclusions: Canine periodontal ligament stem cells have an immunomodulatory effect on allogenic and xenogenic PBMCs. This effect is not a product of apoptosis of PBMCs but is caused by the inhibition of cell division of PBMCs.

/pdf/immunomodulatory-effect-of-canine-periodontal-ligament-stem-4nltxfxcbr.pdf

Immunomodulatory effect of canine periodontal ligament stem cells on allogenic and xenogenic peripheral blood mononuclear cells

In order to improve the mechanical properties of glass fiber–poly(phenylene sulfide) (GF–PPS) composite, silane coupling agents were used to modify the glass fiber surface. RC-2 silane and styryl silane were applied to the surface treatment of glass fiber with various concentrations. The interlaminar shear strength and the flexural strength of the silane treated GF–PPS composite increased compared with the untreated one. The optimum silane concentrations for the glass surface treatment were observed in RC-2 silane and styryl silane, respectively. RC-2 silane was more effective in the enhancement of the interlaminar shear strength and the flexural strength of the GF-PPS composite. © 1996 John Wiley & Sons, Inc.

Hak Sung Kim

Papers

Immunomodulatory effect of canine periodontal ligament stem cells on allogenic and xenogenic peripheral blood mononuclear cells

Performance improvement of glass fiber–poly(phenylene sulfide) composite

An asymmetric total synthesis of (−)-fumagillol

A total synthesis of spirocyclic alkaloids via an intramolecular sn2' lactam enolate alkylation

A stereoselective synthesis of (±)-elemol via an intramolecular SN2′ ester enolate alkylation