ABSTRACT
Liverworts, considered to be the first plant type to successfully make the transition from water to land, can resist different oxidative stress. As characteristic constituents of liverworts, the bibenzyls are efficient antioxidants. In this study, spatial distributions of the bibenzyls within Marchantia polymorpha L., the model species of liverworts, were mapped using airflow-assisted desorption electrospray ionization imaging mass spectrometry. Bibenzyls were found to largely exist in the female receptacle of M. polymorpha, where lunularic acid was found to focus in the central region and bisbibenzyls were enriched in the periphery. The region-specific gene expression and antioxidant activities were characterized. In line with the spatial feature of bibenzyls, higher MpSTCS1A and Mp4CL expression levels and antioxidant ability were exhibited in the archegoniophore. The expression level of MpSTCS1A, and the content of total phenolic acid was increased after UV-B irradiation, suggesting bibenzyls play an important role in UV-B tolerance. Moreover, lunularic acid and extract of archegoniophore at a certain concentration can stimulate the spore germination under normal conditions and UV-B stress. These works broaden our understanding of the significance of bibenzyls in spore propagation and environmental adaptation.
ABSTRACT
OBJECTIVE: To introduce a method to treat kyphosis with universal spine system (USS) and to evaluate its clinical effect. METHODS: From January 2000 to September 2002, 31 patients with kyphosis were treated with "one-stage total vertebral wedge-shaped osteotomy" and internal fixation of USS. The average follow-up time was 12 months (6-31 months). We observed the clinical effect with the spinal column Cobb before operation and after operation, and the osteotomy confluence rate. RESULTS: In 31 patients, the average angle (Cobb) was 89 degrees before operation and 74 degrees after operation; the average rate of correction was 83.15% and the average rate of osteotomy confluence was 96.77%. No screw and rod broke and loosened. CONCLUSION: The USS is the reliable internal fixation instrument for the treatment of kyphosis, can increase the osteotomy confluence rate and improve correcting rate.
