Enzymatic glycosylation of oleanane-type triterpenoids

Abstract

Glycosylation is an effective approach to improve the druggability of natural products by increasing their water solubility. In this work, we report the glycosylation of oleanane-type triterpenoids by a recombinant microbial glycosyltransferase YjiC1. A preliminary screening test indicated YjiC1 exhibited robust capabilities for O-glycosylation of triterpenoids, based on LC/MS analysis. Among the products, two new compounds (2a and 3a), together with a known one (1a), were isolated and characterized. These products exhibited improved water solubility, and 3a showed moderate anti-HIV activities at 100 μM. This reaction provides a facile and efficient approach to synthesize the glucosides of triterpenoids.     

Tryptophan-kynurenine profile in pediatric autoimmune hepatitis

Immunologic Research - The impairment of regulatory T cells (Tregs) is a characteristic feature of autoimmune hepatitis (AIH), and the degradation of tryptophan (Trp) to kynurenine (Kyn), by gamma...     

口呼吸与鼻呼吸儿童牙弓、基骨形态差异的研究

目的：比较口呼吸与鼻呼吸儿童牙弓、基骨形态的差异，探讨呼吸方式与牙弓、基骨形态的关系。方法：通过口鼻气流同步测定系统的随机检测，选择鼻呼吸比例≤70％(口呼吸组)及≥95％(鼻呼吸组)的11～14岁儿童各34人，测量石膏模型，比较其牙弓、基骨形态的差异。结果：①口呼吸儿童与鼻呼吸儿童相比腭盖较高，上颌基骨较窄，形态相对窄长。②口呼吸儿童比鼻呼吸儿童的上颌中、后段牙弓较长，牙弓形态相对窄长，下颌牙弓后段形态也相对窄长。结论：口呼吸可以引起儿童牙弓、基骨形态的改变。     

Differential expression of CR3, FcɛRll and FcγRlll on Polymorphonuclear leukocytes in gingival crevicular fluid

Polymorphonuclear leukocytes (PMNLs) are the most numerous cell population among the cellular infiltrates in gingival crevicular fluid (GCF) and play important roles in the host-defensive system in the gingival crevices. We determined the percentage of neutrophils, cosinophils and basophils in total PMNLs by light microscopic observation using Randolph-methylene blue staining, then assessed flow cytometric differences in the expression of CR3, FcγRIII, FcɛRII. LFA-1α, and LFA-Iβ on PMNL in GCF and peripheral blood (PB) from 21 patients with adult periodontius (AP) and 13 healthy donors. Percentages of basophils and eosinophils were higher in GCF than in PB. In both AP patients and healthy subjects, expression of CR3 and FcɛRll was higher while FeγRIII was lower in GCF than in PB. The statistical analysis showed that the expressions of FcγRIII and FcɛRII on GCF PMNLs were lower in AP patients than in healthy subjects. Expressions of LFA-1α and β on GCF were similar to those on PB PMNLs. PB PMNLs stimulated in vitro with Porphyromonas gingivalts culture supernatant and fMLP displayed an expression pattern of CR3, FcγRIII and FcɛRII on GCF PMNLs. However, C5a and IL-I failed to induce changes in FcγRIII and FcɛRII. The results indicate that GCF neutrophils are activated, present enhanced adhesion and a decreased IgG-binding ability which would reflect that they are at the terminal stage of activation, and that GCF contains a larger eosinophil fraction than in PB. Moreover, these GCF eosinophils appear to be activated.     

犬下颌骨骨折小钛板坚强内固定的组织学观察

目的:评价小钛板用于犬下颌骨线性骨折的效果。方法:选用12只杂种犬,随机分为实验组和对照组2组,于犬左侧下颌骨中段造成线性骨折,实验组应用钛接骨板(MNS104),长4孔钛板和ψ2.0mm×7mm钛钉加以固定;对照组不用任何材料固定。2组均分别于实验的第20天和第40天各取半数动物处死,应用四环素荧光标记方法及组织学观察,评价骨折愈合情况。测算四环素荧光染色切片上荧光带的宽窄,应用SPSS10.0统计软件包进行t检验,比较骨折愈合的速度。结果:小钛板的固定效果显著优于空白对照,四环素荧光染色可见,实验组的成骨速度显著优于空白组,其荧光宽度均值(0.1967mm)显著大于空白组均值(0.0891mm),P<0.05。结论:小钛板可以保证下颌骨骨折一期愈合。