Centimeter-Sized Single Crystals of Tetrahedral Manganese (II) Halide Hybrids for Wide-Color Gamut Backlighting Displays.

Phosphors with narrow-band green emissions and high photoluminescent quantum efficiency (PLQY) are significantly required for backlighting displays with wider color gamut. In this work, two centimeter-sized manganese (II) halide single crystals TMG2 MnCl4 and TMG2 MnBr4 (TMG = 1,1,3,3-tetramethylguanidine) are synthesized, exhibiting bright narrow-band green emissions with high PLQYs up to 62% and 90%, respectively. The narrow-band green light emission is located at 520 nm with a full-width at half-maximum (FWHM) of only 57 nm. The photoluminescence mechanisms of two single crystals are elaborated. Two white-light-emitting diodes for backlighting displays (BD-WLEDs) based on them are fabricated, exhibiting the widest color gamut of 122% National Television Standards Committee (NTSC), and a luminous efficacy reached ≈93 lm W-1 with excellent luminescence stability at high temperatures. These properties indicate the potential applications of tetrahedral manganese (II) hybrids in wide-color gamut backlighting displays.

Co-grafting of neural stem cells with olfactory en sheathing cells promotes neuronal restoration in traumatic brain injury with an anti-inflammatory mechanism.

BACKGROUND: We sought to investigate the effects of co-grafting neural stem cells (NSCs) with olfactory ensheathing cells (OECs) on neurological behavior in rats subjected to traumatic brain injury (TBI) and explore underlying molecular mechanisms. METHODS: TBI was established by percussion device made through a weight drop (50 g) from a 30 cm height. Cultured NSCs and OECs isolated from rats were labeled by Hoechst 33342 (blue) and chloromethyl-benzamidodialkyl carbocyanine (CM-Dil) (red), respectively. Then, NSCs and/or OECs, separately or combined, were transplanted into the area surrounding the injury site. Fourteen days after transplantation, neurological severity score (NSS) were recorded. The brain tissue was harvested and processed for immunocytochemistry, terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL), and reverse transcription-polymerase chain reaction (RT-PCR). RESULTS: Significant neurological function improvement was observed in the three transplant groups, compared to the TBI group, and co-transplantation gave rise to the best improvement. Morphological evaluation showed that the number of neurons in cortex from combination implantation was more than for other groups (P <0.05); conversely, the number of apoptotic cells showed a significant decrease by TUNEL staining. Transplanted NSCs and OECs could survive and migrate in the brain, and the number of neurons differentiating from NSCs in the co-transplantation group was significantly greater than in the NSCs group. At the molecular level, the expressions of IL-6 and BAD in the co-graft group were found to be down regulated significantly, when compared to either the NSC or OEC alone groups. CONCLUSION: The present study demonstrates for the first time the optimal effects of co-grafting NSCs and OECs as a new strategy for the treatment of TBI via an anti-inflammation mechanism.

OECs transplantation results in neuropathic pain associated with BDNF regulating ERK activity in rats following cord hemisection.

BACKGROUND: The olfactory ensheathing cells (OECs) derived from olfactory bulb (OB) may improve motor function after transplantation in injured spinal cord. However, the effects of OEC transplantation on sensory function have not been reported yet. The purpose of this study is to investigate whether OEC transplantation could affect the sensory function and to analyze the underlying mechanism. RESULTS: OEC transplantation into the hemisected spinal cords can result in hyperalgesia, indicated by radiant and mechanical stimuli towards the plantar surface in rats. This could be associated with upregulation of Brain Derived Neurotrophic Factor (BDNF), indicated by RT-PCR. Immunofluorecent staining showed that BDNF was mainly located in the neurons of the laminas I and II of the dorsal horn. Moreover, a notable upregulation on the level of p-ERK (phosphorylation of extracellular signal-regulated kinase), the downstream molecule of BDNF, was detected by using Western Blot. These findings indicate that the increased BDNF level associated with the p-ERK was possibly involved in neuropathic pain in hemisected spinal cord subjected to OEC transplantation. CONCLUSIONS: The transplantation of OECs may induce the noticeable pain hypersensitivity in rats after hemisected spinal cord injury, and the possible mechanism may be associated with the phosphorylation of ERK and the activated BDNF overexpression.

A new series of C-6 unsubstituted tetrahydropyrimidines: convenient one-pot chemoselective synthesis, aggregation-induced and size-independent emission characteristics.

A new series of C-6 unsubstituted tetrahydropyrimidines 6 have been directly synthesized via a convenient urea-catalyzed chemoselective five-component reaction (5CR) under mild conditions. Compounds 6 show typical aggregation-induced emission enhancement (AIEE) characteristics because they are practically no emissive in solution but emit blue or green fluorescence in aggregates with fluorescence yield up to 93%. One of the 5CR products, 6aa, exhibits blue- and green-fluorescence aggregates (bf- and gf-aggregates). The bf- and gf-aggregates are prepared under different conditions and proved to result from different J-aggregations by single-crystal X-ray analysis. In addition, the bf- and gf-aggregates of 6aa show unusual size-independent emission (SIE) characteristics because their maximum emission wavelengths in different sizes (suspension particles, film, powder and crystals) are the same, 434 and 484 nm, respectively. Based on the obtained experimental results, the 5CR mechanism, the origins of AIEE and SIE characteristics are discussed.

Two Novel Two-Dimensional Organic-Inorganic Hybrid Lead Halides with Broadband Emission for White-Light-Emitting Diodes.

Low-dimensional organic-inorganic metal halides (LOMHs) recently have attracted much attention due to their tunable crystal structures and excellent photoelectric properties. The configuration and arrangement of organic cations in LOMHs have significant effect on the structure of inorganic frameworks and luminescence properties. In this work, we systematically explored the "spatial effect" and "hydrogen bonding effect" of organic cations on the structure and properties of LOMHs, by synthesizing three LOMHs including (N-AD)PbCl4, (N-AD)2Pb2Br7, and (N-AD)4Pb3I12 (N-AD: N-acetylethylenediamine, C4H10N2O). Specifically, (110)-oriented two-dimensional (N-AD)PbCl4 and (N-AD)2Pb2Br7 with manifest blue-white emissions, originating from the free excitons (FEs) and self-trapped excitons (STEs), respectively. The UV-pumped light-emitting diode (LED)-based on (N-AD)2Pb2Br7 was prepared, and the highest color rendering index (CRI) and correlated color temperature (CCT) were up to 80 and 4484 K, respectively. This proves its potential application in solid-state lighting.

TMC120 displayed potent cytotoxic effect on human cervical carcinoma through enhancing the polymerization of microtubules.

OBJECTIVE: In the post-HAART era, the incidence of some AIDS-defining cancers declined markedly likely reflecting HAART-related improvements in immunity, whereas incidence of some cancers such as cervical cancer has not been affected. Therefore, it is valuable to find whether antiretroviral drugs or prophylactic microbicides could treat or prevent these cancers, especially the cervical cancer. DESIGN: We screened the anti-HIV drugs, approved or in phase III clinical trials, to identify a potential anticancer drug candidate. METHODS: We chose cervical HeLa and SiHa cancer cells and focused on studying the antitumor effects in vitro and in vivo. Cell proliferation was measured by MTT assay, the cytotoxic effect was obtained through apoptosis as evidenced by Annexin V flow cytometry assay because of the arresting of cancer cells in G2/M phase of cell cycle. Nude mice xenograft model was performed to detect the antitumor effect in vivo. RESULTS: TMC120 was identified as a potential anticancer drug candidate. TMC120 displayed potent cytotoxic effect on various human cancer cells, including cervical carcinoma cell line HeLa and SiHa. Further mechanism study showed that TMC120 enhanced the polymerization of microtubules, which was followed by mitotic arrest, as well as abnormal mitotic spindles. TMC120 also substantially retarded the growth rate of the tumor in vivo. CONCLUSION: TMC120 is a potential chemoprophylactic and therapeutic agent for cervical cancers in a manner similar to paclitaxel, and could be suitable for helping healthy women to prevent HIV infection and cervical cancer.

Combined Bone Mesenchymal Stem Cell and Olfactory Ensheathing Cell Transplantation Promotes Neural Repair Associated With CNTF Expression in Traumatic Brain-Injured Rats.

This study examined the role of bone mesenchymal stem cell (BMSC) and olfactory ensheathing cell (OEC) cografting on neural function and underlying molecular mechanisms in acute stage of traumatic brain injury (TBI) rats. Eighty Sprague-Dawley (SD) female rats were randomly divided into five groups (n = 16 per category): sham operated group (Sham), weight-drop-induced TBI group (TBI), BMSC transplantation group (BMSC), OEC transplantation group (OEC), and cotransplantation group (CO). Eight rats were randomly selected from each group for behavioral and morphological assessment. Another category (n = 8 rats) was employed in the genetic expression detection. BMSCs were isolated from GFP mice and identified by CD44 antibody. OECs were isolated from the SD rats, identified by P75 antibody and labeled by Hoechst 33342. They were then transplanted into the surrounding tissue of the epicenter of TBI rats. The result of neurological severity scores revealed that BMSC or OEC transplantation alone and BMSC and OEC cografting significantly ameliorated the neurological deficits of TBI rats. Quantitative immunohistochemical analysis showed that graft-recipient animals possessed dramatically more neurons and regenerated axons and smaller amounts of astrocytes than controls 14 days posttransplantation (p < 0.05). However, the expressional level of ciliary neurotrophic factor significantly decreased in the cografting group as determined by RT-PCR (p < 0.05), and the Janus kinase/signal transducer and activator of transcription pathway was significantly activated at 7 days after cell transplantation (p < 0.05). This study is the first to report the role of cotransplantation of BMSCs and OECs in the therapy of TBI and explore its potential molecular mechanisms, therefore providing the important morphological and molecular biological evidence for the clinical application of BMSC and/or OEC transplantation in TBI.

A novel synthetic dibenzocyclooctadiene lignan analog XLYF-104-6 attenuates lipopolysaccharide-induced inflammatory response in RAW264.7 macrophage cells and protects BALB/c mice from sepsis.

The wide range of inflammation mechanisms under control by NF-κB makes this pathway as an attractive target for new anti-inflammatory drugs. Herein, we showed that a new dibenzocyclooctadiene lignan analog XLYF-104-6, with a chemical name of 1,2,3,10,11-pentamethoxydibenzocycloocta-6,7-[c] pyrrole-1,3-dione, inhibited lipopolysaccharide (LPS)-induced NF-κB activation in RAW264.7 cells through preventing IκBα degradation and p65 nuclear translocation. The inhibitory activity of this compound on NF-κB activation contributes to the reduction of LPS-induced TNF-α and IL-6 productions. Notably, XLYF-104-6 suppressed LPS-induced iNOS expression and NO production in a NF-κB independent manner, since IKK inhibitor BAY 11-7082 has failed to exert similar inhibitory effect on iNOS expression and NO production. In addition, XLFY-104-6 also exerted anti-inflammatory action in endotoxemic mice by decreasing plasma LPS-induced TNF-α and IL-1ß levels as well as increasing plasma LPS-induced IL-10 concentrations. These findings suggest XLYF-104-6 could act as a leading compound for developing a potential anti-inflammatory drug.

Development of four-component synthesis of tetra- and pentasubstituted polyfunctional dihydropyrroles: free permutation and combination of aromatic and aliphatic amines.

We previously reported the novel efficient proton/heat-promoted four-component reactions (4CRs) of but-2-ynedioates, two same/different primary amines, and aldehydes for the synthesis of tetra- and pentasubstituted polyfunctional dihydropyrroles. If aromatic and aliphatic amines were used as reagents, four different series of products should be obtained via the permutation and combination of aromatic and aliphatic primary amines. However, only three/two rather four different series of tetra-/pentasubstisuted dihydropyrroles could be prepared via the proton/heat-promoted 4CRs. Herein, Cu(OAc)2·H2O, a Lewis acid being stable in air and water, was found to be an efficient catalyst for the 4CR synthesis of all the four different series of tetra-/pentasubstisuted dihydropyrroles. The copper-catalyzed 4CR could produce target products at room temperature in good to excellent yields. Interestingly, benzaldehyde, in addition to being used as a useful reactant for the synthesis of pentasubstituted dihydropyrroles, was found to be an excellent additive for preventing the oxidation of aromatic amines with copper(II) and ensuring the sooth conduct of the 4CRs for the synthesis of tetrasubstituted dihydropyrroles with aryl R(3). In addition, salicylic acid was found to be needed to increase the activities and yields of the copper-catalyzed 4CRs for the synthesis of petasubstituted diyhydropyrroles. On the basis of experimental results, the enamination/amidation/intramolecular cyclization mechanism was proposed and amidation is expected to be the rate-limited step in the copper-catalyzed 4CRs.