Sphingomyelin (SM) is among the most important biomolecules in eukaryotes and acts as both constructive components and signal carrier in physiological processes. SM is catalyzed by a membrane protein family, sphingomyelin synthases (SMSs), consisting of three members, SMS1, SMS2 and SMSr. SMSs modulate sphingomyelin and other sphingolipids levels, thereby regulating membrane mobility, ceramide-dependent apoptosis and DAG-dependent signaling pathways. SMSs was found associated with various diseases. Downregulation of SMS2 activity results in protective effects against obesity, atherosclerosis and diabetes and makes SMS2 inhibitors potential medicines. Structural guided specific drug design could be the next breakthrough, discriminating SMS2 from other homologs.
The two major language contacts in the history of the Chinese language involve the translations of Chinese Buddhist texts in the Medieval Period and Yuan baihua. Both contacts are related to second language acquisition, and dozens of linguistic changes emerged during the contacts. The basic mode leading to linguistic change is duplication of the most distinctive syntactic features of the model language. Language contact caused by second language acquisition is one of the important types in the study of language contact; its special characteristics are salient, and it is an important subject within the study of language contact that should be given more attention.