使用双砷染料标记乙肝病毒使其在活细胞中显像

背景：
       在活细胞中使用绿荧光蛋白（GFP）标记病毒，使其显像，这项技术很好地帮助了人类对病毒的研究。但是GFP标记物是一种大分子片段插入物，并不适合空间结构有限的致密病毒粒子，乙肝病毒（HBV）就是这样一种病毒。
 
目的：
       为了使得活体细胞中的HBV显像，我们使用荧光标记双砷剂染色的联合HBV，追踪在HBV感染细胞中其在胞质中的运动行为。
 
方法：
       使用诱变的方法，我们将小尺寸四半胱氨酸（tetracysteine,TC）标记物(C-C-P-G-C-C)插入至HBV转染细胞表达的HBV核心蛋白不同细胞表位上，TC探针与双砷荧光染料结合。
 
结果：
       通过共焦显微镜和透射电子显微镜（TEM）我们观察到TC标记的核蛋白被双砷剂染色，在细胞内发出特异性荧光，与核衣壳结合并形成荧光病毒体。重组荧光HBV保留了其感染性与野生型一致。此外，HBV颗粒在活体细胞中的运动轨迹揭示了胞内颗粒的运动是依靠微管。
 
结论：
       据我们所知，本实验是首次使用双砷染料标记的荧光HBV病毒颗粒，并让其在活体细胞内的活动轨迹变得可视。这种荧光HBV可能成为一种活体成像方法的高效工具，为将来研究HBV生活周期精细过程以及病毒与宿主之间相互作用提供帮助。

原文阅读：Metoclopramide nasal spray is effective in symptoms of gastroparesis in diabetics compared to conventional oral tablet

Abstract
BACKGROUND:
Delayed gastric emptying symptoms interfere with the absorption of oral medications. Intranasal metoclopramide is being developed as an alternative to oral metoclopramide for patients with diabetic gastroparesis.
METHODS:
To compare the efficacy and safety of metoclopramide nasal spray to oral tablets in diabetic patients with symptoms of gastroparesis, this randomized, open-label, parallel design study randomized subjects to 10 or 20 mg nasal spray or 10 mg tablet four times a day for 6 weeks. Efficacy was evaluated using a total symptom score (TSS).
KEY RESULTS:
Eighty-nine subjects were enrolled. For the intention to treat population, both nasal dose groups (10 and 20 mg) had lower TSS with treatment compared to the oral 10 mg group. The change from baseline in TSS for nasal 20 mg was greater than the oral 10 mg at Week 6 (p = 0.026). For the per-protocol population, there was a significant difference in the TSS between baseline and Week 6 for both the nasal 10 mg (p = 0.026) and the nasal 20 mg (p = 0.008) cohorts compared to the oral 10 mg group. Based on the definition of a responder, 88.9% of subjects who received oral 10 mg, 91.2% who received nasal 10 mg, and 97.1% who received nasal 20 metoclopramide were classified as responders. The side-effect profile of the metoclopramide nasal spray was favorable. More side effects, especially nausea, occurred with the oral tablets.
CONCLUSIONS & INFERENCES:
Metoclopramide nasal spray offers better symptom control than metoclopramide oral tablet in diabetic patients with symptoms of gastroparesis.