Catalyst-Free [3+2] Cycloaddition of Electron-Deficient Alkynes and o-Hydroxyaryl Azomethine Ylides in Water.

A catalyst-free [3 + 2] cycloaddition reaction of electron-deficient alkynes and o-hydroxyaryl azomethine ylides in water was developed, affording pyrroline derivatives in moderate to high yields (up to 90%).

A semisynthetic approach for the simultaneous reaction of grape seed polymeric procyanidins with catechin and epicatechin to obtain oligomeric procyanidins in large scale.

Polymeric procyanidins (PPCs) were the major constituents of procyanidins, while they have poor bioactivity. To better utilize PPCs, a semisynthetic approach for converting PPCs to oligomeric procyanidins (OPCs) was proposed. Grape seed PPCs were simultaneously reacted with catechin (C) and epicatechin (EC) under acid condition. Combining response surface methodology (RSM) and single-factor experiments, an optimized semisynthetic condition was confirmed with the ratio of PPCs with C and EC of 1:1:1, temperature of 40 °C, reaction time of 20 min and 0.1 M methanolic HCl. High-speed counter-current chromatography (HSCCC) was adopted to obtain three fractions from semisynthetic products and preparative-HPLC was used to isolate individual procyanidins. Thirteen B-type procyanidins including monomers, dimers and trimers were got with high yield of 0.8-17.8 mg from 200 mg semisynthetic products and high purity over 91%. The developed semisynthesis combined with separation method was efficient to obtain individual OPCs in preparative scale.

Protective Effect of Grape Seed Procyanidins against H2 O2 -Induced Oxidative Stress in PC-12 Neuroblastoma Cells: Structure-Activity Relationships.

To establish a structure-activity relationship for procyanidins, we verified the cyto-protective effect of 13 grape seed procyanidins, ranging from monomers to trimers against H2 O2 -induced oxidative stress in PC-12 neuroblastoma cells. Our study demonstrated some procyanidins were able to significantly protect PC-12 cells from the H2 O2 -induced cytotoxicity suggesting they possess neuroprotective effects against oxidative stress. Procyanidins' protective effects against oxidative stress mainly depended on their polymerization degree in addition to their structural features. A positive correlation was found between procyanidins' polymerization degree and the protective effect against oxidative stress in PC-12 cells. The presence of 3- or 3'-galloylated groups in the C-ring of procyanidin molecules significantly increased their protective activity as well. These results demonstrated that galloylated high-molecular-mass procyanidins would be of more interesting as promising antioxidant natural compounds. This work for the first time demonstrated the structure-activity relationships of 13 procyanidins' antioxidative stress activity, which could have a significant impact on future development of procyanidins for healthy food products or drugs to treat disease such as neurodegenerative disorders. PRACTICAL APPLICATION: This work evaluated the protective effect of procyanidins against oxidative stress in PC-12 neuroblastoma cells and established their activity-structure relationships, which provides useful cellular evidence for the further investigating the structure-optimizing and function-exploiting of procyanidins.

Application of SonoVue combined with three-dimensional color power angiography in the diagnosis and prognosis evaluation of intrauterine adhesion.

OBJECTIVE: To investigate the significance of the related indexes of three-dimensional color power angiography (3D-CPA) combined with SonoVue angiography in the diagnosis and prognosis evaluation of intrauterine adhesion (IUA). METHODS: The accuracy, sensitivity, and specificity were evaluated between 3D-TVS and hysteroscopy. Endometrial thickness, volume (V), mean gray value (MG), vascularization index (VI), flow index (FI), vascularization flow index (VFI), and other related indexes before and after the angiography were compared. According to the hysteroscopy findings, the patients were divided into three groups: mild, medium, and severe. The endometrial thickness at 3 months postoperatively and the pregnancy rates at 1 year postoperatively were compared. RESULTS: Compared with the hysteroscopy, sensitivity: 0.970 (0.021), specificity: 0.667 (0.086), (the values inside the bracket were the standard error), positive likelihood ratio: 2.909, negative likelihood ratio: 0.045. There was a significant difference in endometrial thickness and V between the three groups (P<0.05), and there was a significant difference in MG, VI, FI, and VFI between the mild and severe group (P>0.05). During intravenous injection of SonoVue, the blood flow of each group increased (P<0.001), and the VI, FI, and VFI of each group were significantly different (P<0.05). Compared with the preoperative values, the endometrial thickness, V, MG, VI, FI, and VFI significantly changed at 3 months postoperatively (P<0.05). The mild group and high VI group had a higher pregnancy success rate at one year postoperatively. CONCLUSION: 3D-CPA can indirectly diagnose IUA, and may play an important role in prognosis assessment.