A pot experiment was conducted to study effect of drought stress on leaf physiological characteristics and growth of one year old Stellaria dichotoma seedlings. The result showed that plant height and shoot dry weight significantly decreased with decrease in soil water content; however, root length and root dry weight increased at light drought stress and decreased at severe drought stress. The result also showed that with the decrease of soil water content, proline content in S. dichotoma leaves decreased then increase, while solube protein content decreased. Activities of SOD and POD in S. dichotoma leaves significantly decreased as soil water content decreased, while activity of CAT significantly decreased at severe drought stress. Membrane permeability in S. dichotoma leaves increased, while MDA content decreased then increased as soil water decreased. These results suggest that S. dichotoma had osmotic stress resistance ability and reactive oxygen scavenging capacity at light drought stress, which caused S. dichotoma growth was no inhibited at a certain extent drought stress.
Droughts ; Plant Leaves ; enzymology ; growth & development ; metabolism ; Plant Proteins ; metabolism ; Plant Roots ; enzymology ; growth & development ; metabolism ; Proline ; metabolism ; Seedlings ; enzymology ; growth & development ; metabolism ; Stellaria ; enzymology ; growth & development ; metabolism ; Water ; metabolism

Background/Aims: To determine the value of salivary pepsin in discriminating sub-types of gastroesophageal reflux disease (GERD) and GERD-related disorders. Methods: Overall, 322 patients with different sub-types of GERD and 45 healthy controls (HC) were studied. All patients took Gastroesophageal Reflux Disease Questionnaire (GerdQ) and underwent endoscopy and 24-hour esophageal pH monitoring and manometry. Salivary pepsin concentration (SPC) was detected by using colloidal gold double-antibody immunological sandwich assay. Oral esomeprazole treatment was administrated in the patients with non-erosive reflux disease (NERD) and extra-esophageal symptoms (EES). Results: Compared to HC, patients with erosive esophagitis, NERD, EES, EES plus typical GERD symptoms, or Barrett’s esophagus had a higher prevalence of saliva and SPC (all P < 0.001). There was no significant difference in the positive rate for pepsin in patients with functional heartburn or GERD with anxiety and depression, compared to HC. After esomeprazole treatment, the positive rate and SPC were significantly reduced in NERD (both P < 0.001) and in EES (P = 0.001 and P = 0.002, respectively). Of the 64 NERD patients, 71.9% (n = 46) were positive for salivary pepsin, which was significantly higher than the rate (43.8%, n = 28) of pathological acid reflux as detected by 24-hour esophageal pH monitoring (P = 0.002). Conclusions Salivary pepsin has an important significance for the diagnosis of GERD and GERD-related disorders. Salivary pepsin and 24-hour esophageal pH monitoring may complement with each other to improve the diagnostic efficiency.