Protective mechanism of salvianolic acid B on blood vessels / 中国中药杂志

Salvianolic acid B(Sal B) is the main water-soluble component of Salvia miltiorrhiza Bunge. Studies have found that Sal B has a good protective effect on blood vessels. Sal B can protect endothelial cells by anti-oxidative stress, inducing autophagy, inhibiting endoplasmic reticulum stress(ERS), inhibiting endothelial inflammation and adhesion molecule expression, inhibiting endothelial cell permeability, anti-thrombosis, and other ways. In addition, Sal B can alleviate endothelial cell damage caused by high glucose(HG). For vascular smooth muscle cell(VSMC), Sal B can reduce the synthesis and secretion of inflammatory factors by inhibiting cyclooxygenase. It can also play a vasodilatory role by inhibiting Ca~(2+) influx. In addition, Sal B can inhibit VSMC proliferation and migration, thereby alleviating vascular stenosis. Sal B also inhibits lipid deposition in the subendothelium, inhibits macrophage conversion to foam cells, and reduces macrophage apoptosis, thereby reducing the volume of subendothelial lipid plaques. For some atherosclerosis(AS) complications, such as peripheral artery disease(PAD), Sal B can promote angiogenesis, thereby improving ischemia. It should be pointed out that the conclusions obtained from different experiments are not completely consistent, which needs further research. In addition, previous pharmacokinetics showed that Sal B was poorly absorbed by oral administration, and it was unstable in the stomach, with a large first-pass effect in the liver. Sal B had fast distribution and metabolism in vivo and short drug action time. These affect the bioavailability and biological effects of Sal B, and the development of clinically valuable Sal B non-injectable delivery systems remains a great challenge.

Prediction of fetal hypoxia by measuring middle cerebral and umbilical artery resistance index in fetuses with umbilical cord around the neck in late pregnancy / 南方医科大学学报

<p><b>OBJECTIVE</b>To investigate the value of middle cerebral artery (MCA) and umbilical artery (UA) resistance index in predicting fetal hypoxia in fetuses with umbilical cord around the neck in late pregnancy.</p><p><b>METHODS</b>Eighty normal fetuses between 38 and 40 weeks of gestation and 88 fetuses with umbilical cord around neck were measured for MCA and UA pulsatility index (PI), resistance index (RI) and the peak-systolic/diastolic ratio (S/D) by means of color Doppler ultrasonography, and the resistance index ratio was calculated. Fetuses with umbilical cord around neck were estimated according to the measured normograms for the presence of fetal hypoxia, and the results were evaluated by diagnostic test.</p><p><b>RESULTS</b>Significant differences were found in MCA and UA resistance index ratio between the groups (P<0.01). There was no significant difference in the resistance index ratio between the normal group and around the neck (one round) group (P>0.05), but significant difference was found between normal group and around the neck (two rounds and more) group (P<0.01), and between the two arounds and one round groups (P<0.05). The sensitivity and specificity of MCA and UA resistance index and resistance index ratio in predicting fetal hypoxia of fetuses with umbilical cord around neck was 43%, 85%, 92%, 83%, 89%, and 100%, respectively.</p><p><b>CONCLUSION</b>MCA and UA resistance index ratio is a better indicator than its resistance index in predicting fetal hypoxia of fetuses with umbilical cord around neck, and may help in early detection of fetal hypoxia for a diagnosis before fetal distress.</p>