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The three molecules of SP-4-An-2, SP-4-An-9 and SP-5-An-9 were synthesized and their fluorescent mechanochromism was studied in their pristine crystalline state and single crystal form, respectively. The molecules have small structure dissimilarity but show quite different responsive behavior to anisotropic grinding and isotropic hydrostatic pressure either in the pristine crystallites or in the single crystals. Manual grinding transfers the ordered pristine crystallites phase to amorphous state, however, it can hardly shift the emission to the longer wavelength, suggesting the ring-opening isomer is rare in the system. As a comparison, hydrostatic pressure compels the anthracene units in the single crystals to be closer with enhanced π-π interaction, and induces the isomerization of spiropyran to be a more flat and conjugated merocyanine (MC) form, resulting in the gradually red-shifted emission and red fluorescence. In particular, the single crystal of SP-4-An-2 achieves a high contrast multicolored change and the largest emission red-shift over 190 nm. These results show the dependency of mechanochromic property on the molecular structure, i.e. marked position of anthracene-to-anthracene, and anthracene-to-spiropyran frameworks based on in-situ observation with the diamond anvil cell (DAC), which is in sharp contrast to the powder crystals and ambient fluorescence measurements.

Aloe barbadensis, A. vera var. chinensis, A. ferox and A. arborescens are the most widely cultivated and used aloe species due to their potential and potent bioactivity. In this study, clot lysis and fibrin plate model were used to assess the in vitro thrombolytic and fibrinolysis activity of protein and phenolic extracts, as well as three pure compounds (aloin A, Aloin B and aloe emodin) from aloe. Meanwhile, the phenolic compounds in aloe were analyzed by high-performance liquid chromatography (HPLC) and LC–mass spectrometry (LC–MS). The in vitro thrombolytic and fibrinolytic activity assay results indicated that the protein and phenolic extracts of four aloe species had good clot lysis, fibrinolytic activity and enzyme activity, and aloin A and aloin B may be the main active ingredients. In addition, the chromatographic analysis shows obviously differences in components, such as aloenin A, isoaloeresin D and aloesin.

An iodine-promoted convenient and environmentally friendly sequential method for the synthesis of trisubstituted methanes bearing a coumarin and a chromone ring is described. The remarkable features of this approach include avoidance of metals, working under air, employment of readily available starting materials, good functional group tolerance and simple operation.

A novel sulfa-Michael/aldol cascade reaction of (E)-3-arylidenechroman-4-ones with 1,4-dithiane-2,5-diol has been developed. This method provides a new practical and facile approach to 4′-hydroxy-2′-aryl-4′,5′-dihydro-2′H-spiro[chroman-3,3′-thiophen]-4-ones with three contiguous stereocenters in high yields. The transformation is atom-economic with good to excellent diastereoselectivities.

The aim of this study is to explore the expression of vascular endothelial growth factor within nasal polyps, and the implication of such expression as regards the development of nasal polyps amongst children.Sixty children suffering from chronic rhinosinusitis were enrolled in this study. Amongst them, 30 patients featured rhinosinusitis with associated nasal polyps. A biopsy specimen was taken from the stalk or the base of the nasal polyp for nasal-polyp sufferers, and the ethmoid sinus for study participants who featured no nasal polyps. The primary lesions biopsied were immunohistochemically stained with a specific endothelial-cell marker and also stained for the presence of vascular endothelial growth factor. The specific level of vascular endothelial growth factor and the mean number of blood vessels present in a visual microscopic (biopsied-specimen) field were calculated under light microscopy (x400).The number of vascular endothelial growth factor-expressing cells for the nasal-polyp group and for the sinusitis group was, respectively, 20.8+/-4.0 and 11.5+/-3.4 per visual field. Correspondingly, the mean intra-polyp blood-vessel density for the nasal-polyp group and that for the control group was, respectively, 10.5+/-2.6 and 5.0+/-1.9 per visual field. The mean intra-polyp blood-vessel density and the number of vascular endothelial growth factor-expressing cells proved to be significantly greater amongst individuals from the nasal-polyp group than was the case for their analogs from the sinusitis group (P0.01, for both). The presence of vascular endothelial growth factor was found to be distributed predominantly within the vascular endothelium and the mast cells of polyp tissue. In addition, the level of vascular endothelial growth-factor expression and the mean blood-vessel count per field correlated significantly for nasal-polyp tissue (P0.001). Furthermore, the relative size of nasal polyps correlated significantly with the number of (intra-polyp) vascular endothelial-cell growth factor-expressing cells and the mean blood-vessel density (P0.05, for both).The level of expression of vascular endothelial-cell growth factor (VEGF) and the mean blood-vessel density were shown to be significantly greater within nasal polyps than within corresponding sinusitis mucosa. Clinically, the expression of both of these parameters correlated well with the relative size of nasal polyps. Vascular endothelial growth factor participates in the formation of nasal polyps amongst children suffering from chronic rhinosinusitis (CRS).