A triphenylamine-based colorimetric and fluorescent probe with donor­bridge­acceptor structure for detection of G-quadruplex DNA.

In this Letter, three triphenylamine-based dyes (TPA-1, TPA-2a and TPA-2b) with donor­bridge­acceptor (D­p­A) structure were designed and synthesized for the purpose of G-quadruplexes recognition. In aqueous conditions, the interactions of the dyes with G-quadruplexes were studied with the aim to establish the influence of the geometry of the dyes on their binding and probing properties. Results indicate that TPA-2b displays significant selective colorimetric and fluorescent changes upon binding of G-quadruplex DNA. More importantly, its distinct color change enables visual detection and differentiation of G-quadruplexes from single and duplex DNA structures. CD titration date reveals that TPA-2b could induce and stabilize the formation of G-quadruplex structure. All these remarkable properties of TPA-2b suggest that it should have promising application in the field of G-quadruplexes research.

3D-printed bioink loading with stem cells and cellular vesicles for periodontitis-derived bone defect repair.

The suitable microenvironment of bone regeneration is critically important for periodontitis-derived bone defect repair. Three major challenges in achieving a robust osteogenic reaction are the exist of oral inflammation, pathogenic bacteria invasion and unaffluent seed cells. Herein, a customizable and multifunctional 3D-printing module was designed with glycidyl methacrylate (GMA) modified epsilon-poly-L-lysine (EPLGMA) loading periodontal ligament stem cells (PDLSCs) and myeloid-derived suppressive cells membrane vesicles (MDSCs-MV) bioink (EPLGMA/PDLSCs/MDSCs-MVs, abbreviated as EPM) for periodontitis-derived bone defect repair. The EPM showed excellent mechanical properties and physicochemical characteristics, providing a suitable microenvironment for bone regeneration.In vitro, EPMs presented effectively kill the periodontopathic bacteria depend on the natural antibacterial properties of the EPL. Meanwhile, MDSCs-MV was confirmed to inhibit T cells through CD73/CD39/adenosine signal pathway, exerting an anti-inflammatory role. Additionally, seed cells of PDLSCs provide an adequate supply for osteoblasts. Moreover, MDSCs-MV could significantly enhance the mineralizing capacity of PDLSCs-derived osteoblast. In the periodontal bone defect rat model, the results of micro-CT and histological staining demonstrated that the EPM scaffold similarly had an excellent anti-inflammatory and bone regeneration efficacyin vivo. This biomimetic and multifunctional 3D-printing bioink opens new avenues for periodontitis-derived bone defect repair and future clinical application.

"Brill Transition" Shown by Green Material Poly(octamethylene carbonate).

Poly(octamethylene carbonate) (POMC), as the eighth member of the newly developed biodegradable aliphatic polycarbonate family, demonstrates a reversible crystal-crystal transition, which is highly similar to Brill transition extensively studied in the nylon family. With the dipole-dipole interaction in POMC much weaker than the hydrogen bonding, POMC exhibits its "Brill transition" temperature at around 42 °C, much lower than nylons. The two crystalline structures of POMC at below and above the transition temperature can be identified. The transition of POMC is largely associated with the reversible conformation change of methylene sequences from trans-dominated at low temperatures to trans/gauche coexistence at high temperatures.

New Perspectives on Specific Immune-Depletion Technique Using Monoclonal Antibodies against Small Active Molecules in Herbs.

One of the main focuses in Chinese Medicine research is the identification of efficacious components in Chinese herbal medicine (CHM). Studies in such area are difficult due to the complexity and the synergistic characteristics of CHM. Current methods to track and separate active components are not adequate to meet the needs of revealing effects and identify substances and pharmacological mechanisms, which directly restrict the modernization and globalization of CHM. In this paper, a new methodology to deplete a single active component via immunoassay was introduced. The specific active component in a CHM mixture can then be identified and studied through comparative analyses of the pharmacological effects before and after immune depletion. With this new methodology, degree of contribution of a particular component to the whole complex herbal mixture can be elucidated, and its synergistic property with other components can be determined. The new method can reflect not only the overall combined pharmacological effects of CHM but also the effect of individual component. It is an effective way to explain the degree of contribution of one specific component to the overall activity of a CHM prescription.

Allelic distributions of CYP2D6 gene copy number variation in the Eastern Han Chinese population.

AIM: The human cytochrome P450 2D6 (CYP2D6) gene copy number variation, involving CYP2D6 gene deletion (CYP2D6*5) and duplication or multiduplication (CYP2D6*xN), can result in reduced or increased metabolism of many clinically used drugs. The identification of CYP2D6*5 and CYP2D6*xN and the investigation of their allelic distributions in ethnic populations can be important in determining the right drug and dosage for each patient. METHODS: The CYP2D6*5 and CYP2D6 genes, and CYP2D6 gene duplication were identified by 2 modified long PCR, respectively. To determine duplicated alleles, a novel long PCR was developed to amplify the entire duplicated CYP2D6 gene which was used as template for subsequent PCR amplification. A total of 363 unrelated Eastern Han Chinese individuals were analyzed for CYP2D6 gene copy number variation. RESULTS: The frequency of CYP2D6*5 and CYP2D6*xN were 4.82% (n=35) and 0.69% (n=5) in the Eastern Han Chinese population, respectively. Of the 5 duplicated alleles, 3 were CYP2D6*1xN and 2 were CYP2D6*10xN. One individual was a carrier of both CYP2D6*5 and CYP2D6*1xN. Taken together, the CYP2D6 gene rearrangements were present in 10.74% of subjects. CONCLUSION: Allelic distributions of the CYP2D6 gene copy number variation differ among Chinese from different regions, indicating ethnic variety in Chinese. Long PCR are convenient, cost effective, specific and semiquantitative for the detection of the CYP2D6 gene copy number variation, and amplification of the entire duplicated CYP2D6 gene is necessary for the accurate identification of duplicated alleles.