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Synthetic studies toward the daphnane and tigliane diterpenes, a large family of natural products from the plant families Euphorbiaceae and Thymelaeaceae , are reported. Retrosynthetic analysis traced these molecules back to an aromatic precursor and several routes were explored in the forward direction to access such motifs. Two strategies ultimately proved capable of forging complex 5,7,6 -fused tricyclic ring systems, one of which proceeded in only seven steps. Image 1 [ABSTRACT FROM AUTHOR]

Background Although the concept of conservative treatment for paediatric condylar fracture is well understood, there is still a lack of a recognized method for treating child patients with a condylar fracture. The purpose of this study was to investigate the effect of the removable occlusal splint in treating condylar fractures in children and adolescents. Materials and methods Forty children and adolescents with condylar fracture, aged 3–16, were included in this study. A removable occlusal splint with varying thickness was fabricated according to the age, developmental stage of the mandible, and degree of condylar dislocation. This was worn for 1–3 months, accompanied by functional exercises. Follow-up was carried out by clinical observation and panoramic X-ray. Results Clinically satisfactory results with good occlusion were obtained in all the patients, along with unimpaired function and normal growth and development of the mandible. The panoramic image showed remodelling and reconstruction of the fractured condyles. Conclusions Our results confirm that conservative treatment has a satisfactory clinical outcome in treating condylar fracture in children. The removable occlusal splint is a promising approach for treating condylar fracture in children and adolescents. [ABSTRACT FROM AUTHOR]

Abstract: The role of voltage-dependent potassium channel currents in glutamate-treated rat hippocampal neurons was investigated. Cell viability was evaluated by MTT reduction assay and morphological changes. Apoptosis was detected by Hoechst33342 staining with fluorescent microscopy and propidium iodide staining with flow cytometry. Membrane potassium channel currents were recorded with whole-cell patch clamp recordings. Results showed that after shortly exposed to glutamate, about 25 and 50% cells died in 3h and 24h, respectively. Meanwhile, the enhancement of I K was observed within 6h after the glutamate insult. TEA selectively blocked I K and significantly reduced cell apoptosis. I A did not change in the insult though 4-AP, the blocker of this current, showed a protective effect against the injury. These data were in consistent with the hypothesis that K+ efflux contributed to glutamate-triggered apoptosis and I K channels might have a therapeutic effect on the treatment of cerebral ischemia. [Copyright &y& Elsevier]

Antiphospholipid antibodies are a family of closely related but heterogeneous autoantibodies that may have different biological and pathogenic properties. The article investigates the distribution of six kinds of Antiphospholipid antibodies (aPL) in the serum of healthy volunteers. Whole peripheral blood samples of 82 healthy volunteers were drawn from blood donors with median age of 39.3 years. The findings suggest that healthy volunteers possess aPL. Some aPL are natural autoantibodies that are present in healthy individuals. Other aPL present in sera from healthy individuals are those that may be uncovered by heating sera at 56 degrees Celsius for 30 minutes.

In this work, we present the details of the first unified chemical synthesis of cephalotaxus diterpenoids with three distinct carbon skeleton structures. Drawing on our previous synthesis of cephalotane-type C18 dinorditerpenoid and inspired by the proposed biosynthetic synthesis pathway, we formulated a biosynthetic reversed chemical synthetic strategy. This strategy facilitated the conversion of C18 dinorditerpenoid into troponoid-type C19 norditerpenoid and intact cephalotane-type C20 diterpenoid through pivotal one-carbon introduction and ring expansion reactions. In the synthesis of troponoid-type C19 norditerpenoid, we utilized TMSCHN 2 as one-carbon unit and meticulously examined the selective regulatory effect of halogen substituents in ring expansion and rearrangement reactions. This endeavor culminated in the successful synthesis of natural product molecules within this subclass, notably including cephinoid H and fortalpinoid C, marking the first chemical total synthesis in this line of research. In the investigation of intact cephalotane-type C20 diterpenoid synthesis, while adhering to the overall synthesis strategy, we initially pursued a ring expansion before carbon introduction approach, which proved unsuccessful. Subsequently, we explored a synthetic route of introducing carbon first and then expanding the ring, leading to a successful outcome and resulting in the first chemical total synthesis of the representative molecule cephanolide E within this subclass. Various challenges such as establishing crucial quaternary carbon stereocenters, selecting appropriate one-carbon units, and controlling ring expansion reactions were effectively addressed throughout this process. Moreover, enantioselective synthesis of natural products within this family was achieved through the development of asymmetric Michael reactions. A detailed research summary is presented for introducing the unified total synthesis of three subgroups of cephalotaxus diterpenoids, with a novel synthetic route possessing a reverse order with potential biosynthetic route. The troponoid-type C19 norditerpenoids cephinoid H and fortalpinoid C could be synthesized from cephalotane-type C18 dinorditerpenoid-cephanolide B through regioselective ring expansion modulated by introducing a chlorine atom at the C15 site. For intact cephalotane-type C20 diterpenoids, we develop two synthetic routes to explore their syntheses from cephalotane-type C18 dinorditerpenoid-cephanolide B, involving ring expansion/C17-introduction and its reverse process. The first synthetic route is unsuccessful due to the great difficulty of C17-introduction and the first total synthesis cephalotane-type C20 diterpenoid cephanolide E is finally realized via the second synthetic route. [Display omitted] [ABSTRACT FROM AUTHOR]

[Display omitted] • Poly (poly (ethylene glycol) methacrylate) (PPEGMA) was grafted onto PP separator by N-hydroxyphthalimide (NHPI) catalysis combined with ARGET-ATRP. • Electrolyte wettability of PPEGMA functionalized PP was enhanced evidently compared to that of pristine PP separator. • Rate performance and long cycle ability for cell with the modified PP separator was improved significantly. • The proposed strategy was also applied to modify other polyolefine membranes for advanced applications. Surface modification of polyolefine separators for high performance lithium-ion batteries has been a worthwhile research topic. In this work, poly (poly (ethylene glycol) methacrylate) (PPEGMA) was firstly grafted onto polypropylene (PP) separator based on N-hydroxyphthalimide (NHPI) catalysis and activators regenerated by electron transfer atom transfer radical polymerization (ARGET-ATRP). Bis(2,2,2-trichloroethyl) azodicarboxylate (BTCEAD) was anchored on the surface of PP separators in the presence of NHPI. Then BTCEAD functionalized PP separator initiated the polymerization of PEGMA by ARGET-ATRP. Thus, structure controllable PPEGMA was grafted on the surface of PP separators. The results of contact angle and electrolyte uptake tests demonstrated that electrolyte wettability of PPEGMA functionalized PP separator has been significantly improved. Electrochemical measurements indicated that the ionic conductivity and discharge capacity retention of cells assembled with PPEGMA functionalized PP separators were distinctly higher than that of cells with pristine PP separator. Herein, we presented a new methodology with high efficiency to modify PP separators under mild condition, which was also applied to other polyolefine separator for high performance lithium-ion batteries. The proposed approach might have many other potential applications in membrane modification field. [ABSTRACT FROM AUTHOR]

Two hole transporting materials (HTMs), SFX-PT1 and SFX-PT2 , were designed and synthesized by combing a spiro[fluorene-9, 9′-xanthene] (SFX) core with tetra- phenothiazine substituted at the 2,2′,7,7′- and 2,3′,6,′7-positions, respectively. As comparison, a HTM with tetra-phenothiazine substituted at the 2,2′,7,7′-positions of a 9, 9′-spirobifluorene core ( Spiro-PT ) was also synthesized. Their photophysical and electrochemical properties, thermal stability and hole mobility were investigated. It was demonstrated that SFX-centered HTMs exhibited superior Stokes shift, thermal stability and hole mobility than those of Spiro-PT . Combining with the substituted positions modification, SFX-PT1 has the largest Stokes shift of 197 nm, the highest decomposition temperature of 435 °C and hole mobility of 2.08 × 10 −3 cm 2 V −1 S −1 . Moreover, the energy levels of the HTMs were matched very well with that of CH 3 NH 3 PbI 3 . Our results indicated that SFX-centered, phenothiazole substituted HTMs might be potential candidates for efficient perovskite solar cells. [ABSTRACT FROM AUTHOR]