A light-responsive molecular switch based on cucurbit[7]uril and 1,1'-bis(benzyl)-4-[2-(4-pyridyl)-vinyl]-pyridinium dibromide displaying white light emission.

By using 1H NMR, ESI-MS and UV spectra, a novel light-responsive molecular switch constructed using 1,1'-bis(benzyl)-4-[2-(4-pyridyl)-vinyl]-pyridinium (12+) and cucurbit[7]uril (Q[7]) is demonstrated. The E- to Z-isomerization of the double bond in 12+ results in the transition of the switching states from the 1 : 2 complex E-12+@Q[7]2 to the stable 1 : 1 complex Z-12+@Q[7]. In particular, both the 1 : 2 complex and the 1 : 1 complex can emit cold white fluorescence under UV light.

An inclusion complex of cucurbit[7]uril with benzimidazolyl benzyl viologen exhibits fluorescence and photochromic properties.

In order to investigate the photochromic mechanism of photochromic materials based on supramolecular host-guest systems, we designed and synthesized a unique viologen derivative (benzimidazolyl benzyl viologen, guest 1·Cl3), which does not contain oxygen atoms. The binding interaction of guest 13+ with host cucurbit[7]uril (Q[7]) was investigated by various techniques. The obtained supramolecular host-guest complex 13+@Q[7] exhibits interesting fluorescence emission and reversible photochromism. The ESR and XPS experimental data suggest that the photochromic process of the complex 13+@Q[7] comes from the electron transfer from the carbonyl O atoms of the host Q[7] to the bipyridinium N atoms of the guest 13+.

Supramolecular Host-Guest Hydrogel Based on γ-Cyclodextrin and Carboxybenzyl Viologen Showing Reversible Photochromism and Photomodulable Fluorescence.

Much effort has been devoted to the development of supramolecular hydrogels due to their broad applications and conveniently controllable properties. Here, we demonstrate a novel supramolecular host-guest hydrogel, which is constructed by the host γ-CD complexed with the guest 1-(4-carboxybenzyl)-4,4'-bipyridinium chloride (1+·Cl-) through the π···π interaction, hydrogen bonding, and host-guest interactions. The supramolecular hydrogel [1+@γ-CD]n exhibits reversible electron transfer photochromic behavior and photomodulable fluorescence. The excellent photochromic and fluorescence properties support the practical utility of the supramolecular hydrogel as a visual display and anti-counterfeiting material.

[Effect of dragon's blood extract on periodontal tissue repair and TLR4/NF-κB signal pathway].

PURPOSE: To discuss the effects of dragon's blood extract, a Chinese herb, on periodontal tissue repair and toll like receptor 4/nuclear transcription factor kappa B(TLR4/NF-κB) in gingivitis rats. METHODS: Sixty rats were randomly divided into control group, gingivitis group and low, medium and high dose groups of dragon's blood extract, with 10 rats in each group. Except the control group, the gingivitis rat model was established by silk thread ligation in other groups. The model was established successfully. The low, medium and high dose groups rats were given 150, 300 and 600 mg·kg-1·d-1 dragon's blood extract successively by gavage (once a day for 4 weeks). Rats in the model group and the control group were given the same amount of normal saline by gavage at the same time. After the rats were sacrificed under anesthesia, the jaw tissue of the left maxillary second molar was stained with methylene blue to observe and measure the loss of alveolar bone (ABL), H-E staining was used to observe the pathological changes of periodontal tissue (jaw tissue). The levels of IL-17 and IL-4 in periodontal tissue (jaw tissue) of rats in each group were detected by enzyme-linked immunosorbent assay (ELISA). Bone morphogenetic protein-2(BMP-2), TLR4 and NF-κB p65 protein level in rat periodontal tissue were detected by Western blot. SPSS 19.0 software package was used to analyze the data. RESULTS: Compared with the control group, IL-17, IL-4, TLR4 and NF-κB p65 protein and ABL in jaw tissue of model group were significantly increased (P＜0.05), and the level of BMP-2 protein in jaw tissue significantly decreased (P＜0.05). Compared with the model group, IL-17, IL-4, TLR4 and NF-κB p65 protein and ABL in jaw tissue of rats in low, medium and high dose groups of dragon's blood extract were significantly increased, and the level of BMP-2 protein significantly decreased(P＜0.05). CONCLUSIONS: Dragon's blood extract can inhibit TLR4/NF- κB. Activation of B pathway inhibits inflammatory response and promotes periodontal tissue repair in gingivitis rats.

[Clinical and prognostic significance of podoplanin-positive lymphatic vessel density in non-small cell lung carcinoma].

OBJECTIVE: The aim of this study was to investigate the clinical and prognostic significance of lymphangiogenesis in non-small cell lung carcinoma (NSCLC). METHODS: The expression of lymphatic vessel endothelium markers podoplanin, VEGFR-3 and vascular endothelium marker CD31 was detected in paraffin sections from 68 cases of NSCLC and 8 cases of pulmonary inflammatory myofibroblastic tumor (PIMT) by immunohistochemistry (SP). Microvessel density (MVD) and lymphatic vessel density (LVD) were counted. Specificity of lymphatic vessel endothelium markers was compared between VEGFR-3 and podoplanin. Lymphangiogenesis, quantified by evaluating LVD, was correlated with various clinical pathological parameters and prognostic relevance. RESULTS: No significant association was found between the number of podoplanin positive vessels and the number of CD31 positive or VEGFR-3 positive vessels (r = -0.171, P = 0.124; r = 0.003, P = 0.979), but the counts of VEGFR-3 positive vessels were associated with CD31 positive vessel counts (r = 0.331, P = 0.002). LVD in PIMT group was significantly lower than that in NSCLC group (P = 0.004). Compared with that without the lymph node metastasis group, LVD in the positive group increased significantly (P = 0.033); LVD in pathological stage III and IV was higher than that in pathological stage I and II (P = 0.001). There was no difference of LVD in different cell differentiation, age and sex groups. The 5-year survival rate for high LVD was significantly lower than that of low LVD. Multivariate analysis showed that LVD was a significant and independent prognostic factor. CONCLUSIONS: Lymphangiogenesis may be a significant prognostic factor for NSCLC.

Pediatric esophageal leiomyosarcoma: a case report.

Esophageal leiomyosarcoma accounts for only 0.5% of all esophageal tumors. This rare tumor has been reported in middle-aged or elderly patients. In contrast, pediatric esophageal leiomyosarcomas have never been reported. The case described herein is the first report of an esophageal leiomyosarcoma in a pediatric patient with its own characteristics. The patient had symptoms of mild cough without dysphagia. The lesion grew rapidly and reached dimensions of 7.0 cm × 5.0 cm × 6.0 cm in a 3-month period. On computed tomography scan of the chest, the mass exhibited mild enhancement after injection of a contrast agent. More evident enhancement was found on the 3-minute delayed enhanced computed tomography scan. A Phemister operation (transthoracic esophagectomy and esophagogastrostomy) was performed on the patient. The patient did not receive adjuvant postoperative radiotherapy or chemotherapy. He has been followed for 3 years and is free of disease.