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X.‐X. Shi H. Zhang M. Chen Y.‐D. Zhang M.‐F. Zhu M.‐J. Zhang F.‐Q. Li S. Wratten W.‐W. Zhou C. Mao Z.‐R. Zhu 《Insect molecular biology》2019,28(2):253-263
Although sphingomyelins known to be are lipid constituents of the plasma membrane in vertebrates, much remains obscure about the metabolism of sphingomyelins in insects. With ultra performance liquid chromatography‐time‐of‐flight‐tandem mass spectrometry analysis, we revealed for the first time that sphingomyelins are abundant in Nilaparvata lugens (Stål), the brown planthopper (BPH), and their biosynthesis is carried out by sphingomyelin synthase‐like protein 2 (SMSL2), which is homologous to sphingomyelin synthase‐related protein (SMSr). Unlike other insect species, high concentrations of sphingomyelins rather than ceramide phosphoethanolamines exist in the BPH. Two putative genes, which are homologous to SMSr, are named Nilaparvata lugens SMS‐like 1 (NlSMSL1) and 2 (NlSMSL2). Knockdowns of both NlSMSL2 and NlSMSL1 were conducted but only the first decreased concentrations of sphingomyelins in the BPH, indicating that NlSMSL2 plays a role in the biosynthesis of sphingomyelins. Real‐time quantitative PCR analysis revealed both NlSMSL1 and NlSMSL2 are highly expressed in BPH adults, with NlSMSL1 specifically highly expressed in reproductive organs (ovaries and testes) whereas NlSMSL2 was highly expressed in the malpighian tubules. The knockdown of NlSMSL1 or NlSMSL2 increased BPH female body weight but not that of males, suggesting sex‐specific roles for SMSLs in influencing BPH body weight. The results suggest that NlSMSL2 catalyses the synthesis of sphingomyelins and maintains female BPH body weight through alteration of sphingolipid content. 相似文献
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P. Wang Z. Zhang Y. Wang X. Li B. Ye J. Li 《International journal of oral and maxillofacial surgery》2019,48(3):341-346
Hemifacial microsomia (HFM) is a common congenital craniofacial deformity with a high prevalence. Orthognathic surgery and distraction osteogenesis are two conventionally used treatments of HFM. The main objective of this retrospective study was to evaluate the accuracy of two treatments with the help of virtual surgical planning in adult HFM patients. Sixty-eight adult patients with unilateral HFM were enrolled in this study. Preoperative surgical planning and simulation were performed on three-dimensional computed tomography models. Orthognathic surgery or distraction osteogenesis was performed under the guidance of three-dimensional surgical templates. Postoperative evaluation of the intervention was performed by comparison of the affected ramus height, chin deviation and the occlusal cant in surgical planning and actual result. Outcome and feedback information (an average of 14 months) showed that virtual surgical planning was accurately transferred to actual surgery in both surgical approaches. There were no statistical differences between the accuracy of affected ramus height and the occlusal cant in two surgical approaches. The orthognathic group showed significantly higher accuracy in chin deviation. In conclusion, virtual surgical planning and three-dimensional surgical templates were proved to facilitate treatment planning and offer an accurate surgical result in the treatment of adult HFM patients. 相似文献
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