[Expression and clinical significance of SSH1 in gastrointestinal stromal tumors].

Objective: To investigate the correlations between the expression of the slingshot-1(SSH1) and the general clinicopathological factors in gastrointestinal stromal tumor (GIST) patients. Methods: Immunohistochemical staining was used to detect the expression of SSH1 protein in 96 gastrointestinal stromal tumors, and the correlations between expression level of SSH1 and general clinicopathological factors were analyzed. Results: Totally, there were 96 cases of GIST patients (49 males and 47 males), with a mean age of (55.80±12.33) years. The tumors were located in different organs: 62 cases (64.6%) in the stomach, 29 cases (30.2%) in the intestine, and 5 cases (5.2%) in other organs, with a mean tumor size of (5.11±3.73) cm. The low risk group contained 57 cases (59.4%), 18 cases (18.8%) in middle risk group and 21 cases (21.9%) in high risk group. The pathological examination showed that the positive expression rate of CD117, CD34, DOG-1, Ki-67, SMA, S-100 and Desmin was 85.4%, 84.4%, 86.5%, 90.6%, 10.4%, 3.1% and 2.1%, respectively. In 96 cases of GIST, 37 cases (38.5%) had high expression of SSH1, and SSH1 expression level was correlated with the tumor invasion depth, risk classification, tumor mitotic figure count, CD34(+) (P<0.05). Conclusions: SSH1 plays an important role in the development of GIST. High expression of SSH1 is closely related to the invasion depth, risk classification and tumor mitosis of GIST.

ß-ODAP accumulation could be related to low levels of superoxide anion and hydrogen peroxide in Lathyrus sativus L.

Level of the neuroexcitatory ß-N-oxalyl-L-α,ß-diaminopropionic acid (ß-ODAP) in grass pea (Lathyrus sativus L.) varies with development and environmental stress. Reactive oxygen species (ROS) (mainly O(2)ⁱ- and H(2)O(2)) are frequently reported to play important roles in plant development and in response to various stresses. To investigate the possible inter-relationship between contents of ß-ODAP and ROS, grass pea leaves have been analyzed for contents of ß-ODAP, O(2)ⁱ- and H(2)O(2). The results showed that leaves containing high levels of ß-ODAP, exhibited low levels of O(2)ⁱ- and H(2)O(2), while leaves with high contents of O(2)ⁱ- and H(2)O(2) accumulated little ß-ODAP. The application of pyridine or ABA which inhibit the production of O(2)ⁱ- or H(2)O(2) led to an increase in ß-ODAP contents in intact or detached young leaves, whereas inhibition of catalase activity using AT (3-amino-1,2,4-triazole), leading to an increase in H(2)O(2) content, result in significant decrease in ß-ODAP levels of detached young leaves. In addition, inoculation of Rhizobium to young seedlings enhanced O(2)ⁱ- and H(2)O(2) levels, but reduced ß-ODAP contents in shoots. These results suggest that ß-ODAP accumulation could be related to low levels of superoxide anion and hydrogen peroxide in grass pea tissues.

Factors affecting ß-ODAP content in Lathyrus sativus and their possible physiological mechanisms.

A neuroexcitatory non-protein amino acid, ß-N-oxalyl-L-α,ß-diaminopropionic acid (ß-ODAP), present in the seeds of the hardy legume crop grass pea (Lathyrus sativus L.), was considered responsible for human lathyrism. The levels of ß-ODAP were reported to vary in different tissues during plant development, and to be affected by a wide range of environmental stresses. In this paper, dynamic changes in ß-ODAP level at specific stages of plant development as well as the influences of various environmental factors, including nutrient deficiency, drought, salinity, toxic heavy metals, and Rhizobium symbiosis on ß-ODAP levels were analyzed, highlighting the relationship between changes in ß-ODAP concentrations and Rhizobium growth. Possible mechanisms underlying ß-ODAP accumulation are proposed and future research is suggested.