ABSTRACT
Houttuynia cordata Thunb. is an edible herb with a variety of pharmacological activities, but only limited information is available about its response towards potassium supplementation. Sterile plantlets were cultured in media with different potassium levels, and parameters related to growth, foliar potassium, water and chlorophyll contents, photosynthesis, transpiration, H2O2 contents and antioxidative enzyme activities were determined after a month. Results showed that 1.28 mM potassium was the optimum for H. cordata as highest values of dry weight, shoot height, root length and number were obtained at this concentration. The optimum potassium concentration resulted in the maximum net photosynthetic rate which could be associated with the highest chlorophyll content rather than limited stomatal conductance. The supply of surplus potassium resulted in higher content of foliar potassium, but negatively correlated with the biomass. Both potassium starvation (0 mM) and high potassium (>1.28 mM) could lead to water loss through high transpiration rate and low water absorption, respectively, and resulted in H2O2 accumulation and increased activities of catalase and peroxidase, which suggested induction of oxidative stress. Moreover, H. cordata showed the minimum of H2O2 content and the maximum of superoxide dismutase activity on 1.28 mM potassium, implying its role in inducing tolerance against oxidative stress.
ABSTRACT
<p><b>OBJECTIVE</b>To evaluate the predictive value of portal vein flow rate preoperative for portal vein thrombosis (PVT) after periesophagastric devascularization in hepatitis B cirrhosis-related portal hypertension.</p><p><b>METHODS</b>From January 2007 to July 2008, 45 patients with portal hypertension caused by hepatitis B cirrhosis were performed splenectomy with peri-esophagogastric devascularization in the same medical group in West China Hospital of Sichuan University. The portal vein flow rate and the diameter of portal vein were measured with doppler sonography respectively before and after the operation. At the same time, the level of PT and PLT were detected. The weight of spleens were measured after operation.</p><p><b>RESULTS</b>Thirteen cases suffered from PVT postoperatively. Portal vein flow rate was significantly lower in patients with PVT postoperation than that in patients without PVT (P < 0.01). In patients with PVT (n = 13) postoperation, the preoperative portal vein flow rate was (19.5 +/- 5.3) cm/s. Among the 13 cases, there were 12 cases whose flow rate were lower than 25 cm/s, and 1 case whose flow rate was 32. 3 cm/s; In patients without PVT (n = 32), the preoperative portal vein flow rate was (9.6 +/- 8.0) cm/s. In patients with lower rate (n = 17), the incidence rate of PVT was 70.6%; in patients with higher rate (n = 28), the incidence rate of PVT was 3.6%. The incidence rate of PVT in patients with lower rate was significantly lower than patients with higher rate (P < 0.01). The diameter of portal vein in patients with PVT was significantly wider than patients without PVT. The diameter of portal vein was negative correlative with the portal vein flow rate. The value 25 cm/s was of diagnostic efficiency, the sensitivity was 92.3%, and specificity was 70.6%.</p><p><b>CONCLUSIONS</b>The portal vein flow rate preoperative can be used as an early predictor of portal vein thrombosis after periesophagastric devascularization in hepatitis B cirrhosis-related portal hypertension to give a guide to clinical work.</p>
