RESUMO
Shape complementarity is a biological craft for precisely binding substrates at protein-protein interfaces. An analogy to such a function can be drawn conceptually for crystalline porous solids; yet the manifested entities are rare in reticular chemistry. The bottleneck-shaped pores carved out of a metal-organic framework, Zn(MIBA)2 (aka. MAF-stu-13), can perfectly accommodate benzene molecules. Remarkably, its framework adapts to the optimal guest binding-the enhanced host-guest interactions in the neck in turn minimize the guest-guest repulsion in the pore to the extent it turns into attraction-as demonstrated by the combined X-ray structural and DFT computational studies. This adaptive material can be used for liquid-phase production of ultrahigh-purity (≥99 %) cyclohexane, achieving a balance between uptake capacity and separation selectivity and surpassing the performances of other porous and nonporous crystals reported recently (e.g. product purity 99.4 % vs. 97.5 % to date).
Assuntos
Cicloexanos/isolamento & purificação , Imidazóis/química , Estruturas Metalorgânicas/química , Cicloexanos/química , Modelos Moleculares , Tamanho da PartículaRESUMO
Chlorogenic acid (CGA), which is a natural compound found in various plants, has been reported to exert notable antiinflammatory activities. The present study investigated the effects and underlying mechanism of CGA on interleukin (IL)1ßinduced osteoarthritis (OA) chondrocytes. An in vitro OAlike chondrocyte model was established using IL1ßstimulated human SW1353 chondrocytes. Cell viability was assessed using an MTT assay. Nitric oxide (NO) and IL6 production were evaluated by Griess reaction and ELISA, respectively. The expression levels of inducible nitric oxide synthase (iNOS), prostaglandin E2 (PGE2), cyclooxygenase 2 (COX2), collagen II, matrix metalloproteinase (MMP)13, p65 nuclear factor (NF)κB and inhibitorκBα were detected by western blot analysis. The results indicated that CGA reversed IL1ßinduced increases in iNOS/NO, IL6, MMP13 and COX2/PGE2 production, and reversed the IL1ßmediated downregulation of collagen II. In addition, the data suggested that CGA was capable of inhibiting the IL1ßinduced inflammatory response, at least partially via the NFκB signaling pathway. In conclusion, CGA may be considered a suitable candidate agent in the treatment of OA.
Assuntos
Ácido Clorogênico/farmacologia , Condrócitos/patologia , Inflamação/patologia , Inflamação/prevenção & controle , Interleucina-1beta/toxicidade , Modelos Biológicos , Osteoartrite/patologia , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Ácido Clorogênico/química , Condrócitos/efeitos dos fármacos , Condrócitos/metabolismo , Colágeno Tipo II/metabolismo , Ciclo-Oxigenase 2/metabolismo , Dinoprostona/metabolismo , Humanos , Interleucina-6/metabolismo , Metaloproteinase 13 da Matriz , Inibidor de NF-kappaB alfa/metabolismo , NF-kappa B/metabolismo , Óxido Nítrico/metabolismo , Óxido Nítrico Sintase Tipo II/metabolismo , Osteoartrite/metabolismo , Transdução de Sinais/efeitos dos fármacosRESUMO
OBJECTIVE: To analyse the inhibition effect of taspine derivatives on human Liver cancer SMMC7721 cell and its mechanism. METHODS: The effects of five taspine derivatives on SMMC7721 cell growth were determined by MTT. The flow cytometry was used to determine the cell cycle. The effects of Tas-D1 on the EGF and VEGF in SMMC7721 cell were determined by ELISA. The mRNA level of EGF and VEGF in SMMC7721 cell was determined by RT-PCR. RESULTS: The MTT assay demonstrated that the taspine derivative Tas-D1 significantly inhibited the growth of SMMC7721 cell in a dose-dependent manner. Cell was stopped at S phase by Tas-D1. Tas-D1 inhibited the expression of EGF and VEGF and their mRNA in a dose-dependent manner (P<0.05). CONCLUSIONS: The taspine derivative Tas-D1 can inhibit the growth of human Liver cancer SMMC7721 cell and change cell cycle, which may be related to the inhibition of EGF and VEGF expression.
