地鳖纤溶蛋白口服时间/pH依赖结肠靶向微囊的开发及评价＊

地鳖中的纤溶活性蛋白是从地鳖中提取的具有抗栓及抗肿瘤作用的有效成分，其口服易被上消化道酶分解从而限制了应用。采用恒流泵滴制法开发地鳖纤溶活性蛋白时间/pH依赖口服结肠靶向微囊（EnpolypHaga fibrinolytic protein oral colon targeting microcapsules， CTM-EFP）。采用单因素实验和正交实验相结合的方法寻找到包封率为60.17 % ± 2.72 %、载药量为15.50 % ± 0.44 % 的最佳配方。扫描电子显微镜（SEM）显示微囊呈球形、表面光滑，在人工肠液中24 h的累积释放度为99.53 % ± 0.69 %，在人工胃液中24 h累积释放度为7.43 ± 1.04 %，通过时间/pH依赖达到结肠靶向作用。CTM-EFP在人工肠液中的体外释放曲线符合Korsmeyer方程，提示地鳖纤溶活性蛋白（EnpolypHaga fibrinolytic protein， EFP）是通过扩散和侵蚀机制结合释放的。CTM-EFP为EFP的口服给药提供了一种新的剂型，为EFP应用于临床提供参考。     

A prime-boost concept using a T-cell epitope-driven DNA vaccine followed by a whole virus vaccine effectively protected pigs in the pandemic H1N1 pig challenge model

Influenza A virus (IAV) vaccines in pigs generally provide homosubtypic protection but fail to prevent heterologous infections. In this pilot study, the efficacy of an intradermal pDNA vaccine composed of conserved SLA class I and class II T cell epitopes (EPITOPE) against a homosubtypic challenge was compared to an intramuscular commercial inactivated whole virus vaccine (INACT) and a heterologous prime boost approach using both vaccines. Thirty-nine IAV-free, 3-week-old pigs were randomly assigned to one of five groups including NEG-CONTROL (unvaccinated, sham-challenged), INACT-INACT-IAV (vaccinated with FluSure XP® at 4 and 7 weeks, pH1N1 challenged), EPITOPE-INACT-IAV (vaccinated with PigMatrix EDV at 4 and FluSure XP® at 7 weeks, pH1N1 challenged), EPITOPE-EPITOPE-IAV (vaccinated with PigMatrix EDV at 4 and 7 weeks, pH1N1 challenged), and a POS-CONTROL group (unvaccinated, pH1N1 challenged). The challenge was done at 9 weeks of age and pigs were necropsied at day post challenge (dpc) 5. At the time of challenge, all INACT-INACT-IAV pigs, and by dpc 5 all EPITOPE-INACT-IAV pigs were IAV seropositive. IFNγ secreting cells, recognizing vaccine epitope-specific peptides and pH1N1 challenge virus were highest in the EPITOPE-INACT-IAV pigs at challenge. Macroscopic lung lesion scores were reduced in all EPITOPE-INACT-IAV pigs while INACT-INACT-IAV pigs exhibited a bimodal distribution of low and high scores akin to naïve challenged animals. No IAV antigen in lung tissues was detected at necropsy in the EPITOPE-INACT-IAV group, which was similar to naïve unchallenged pigs and different from all other challenged groups. Results suggest that the heterologous prime boost approach using an epitope-driven DNA vaccine followed by an inactivated vaccine was effective against a homosubtypic challenge, and further exploration of this vaccine approach as a practical control measure against heterosubtypic IAV infections is warranted.     

Stabilization and formulation of a recombinant Human Cytomegalovirus vector for use as a candidate HIV-1 vaccine

Live attenuated viral vaccine/vector candidates are inherently unstable and infectivity titer losses can readily occur without defining appropriate formulations, storage conditions and clinical handling practices. During initial process development of a candidate vaccine against HIV-1 using a recombinant Human Cytomegalovirus vector (rHCMV-1), large vector titer losses were observed after storage at 4 °C and after undergoing freeze-thaw. Thus, the goal of this work was to develop candidate frozen liquid formulations of rHCMV-1 with improved freeze-thaw and short-term liquid stability for potential use in early clinical trials. To this end, a virus stability screening protocol was developed including use of a rapid, in vitro cell-based immunofluorescence focus assay to quantitate viral titers. A library of ∼50 pharmaceutical excipients (from various known classes of additives) were evaluated for their effect on vector stability after freeze-thaw cycling or incubation at 4 °C for several days. Certain additives including sugars and polymers (e.g., trehalose, sucrose, sorbitol, hydrolyzed gelatin, dextran 40) as well as removal of NaCl (lower ionic strength) protected rHCMV-1 against freeze-thaw mediated losses in viral titers. Optimized solution conditions (e.g., solution pH, buffers and sugar type) slowed the rate of rHCMV-1 titer losses in the liquid state at 4 °C. After evaluating various excipient combinations, three new candidate formulations were designed and rHCMV-1 stability was benchmarked against both the currently-used and a previously reported formulation. The new candidate formulations were significantly more stable in terms of reducing rHCMV-1 titer losses after 5 freeze-thaw cycles or incubation at 4 °C for 30 days. This case study highlights the utility of semi-empirical design of frozen liquid formulations of a live viral vaccine candidate, where protection against infectivity titer losses due to freeze-thaw and short-term liquid storage are sufficient to enable more rapid initiation of early clinical trials.     

Is the pepsin immunohistochemical staining of laryngeal lesions an available way for diagnosing laryngopharyngeal reflux

Abstract

Backgound: Pepsin immunohistochemical (IHC) staining is a promising diagnostic approach of laryngopharyngeal reflux (LPR). The interarytenoid mucosa has been proved to be an effective biopsy area.

Objectives: To investigate whether positive result of pepsin IHC staining in laryngeal lesions can predict LPR.

Methods: The study included 136 patients with laryngeal cancer or vocal cord leukoplakia. 24?h multichannel intraluminal impedance-pH (MII-pH) was performed before operation, and pepsin IHC staining was performed on pathological sections after operation. The results of the two methods were compared.

Results: Among the 136 patients, 101 with at least one LPR event were regarded as MII-pH positive group, and another 35 were negative. The positive rate of pepsin IHC staining was 93.1% in MII-pH positive group and 54.1% in MII-pH negative group (p?<?.05). If the MII-pH results were used as a reference, the sensitivity and specificity of pepsin IHC staining in the diagnosis of LPR were 93.1 and 45.7%, respectively. The consistency of pepsin IHC and MII-pH was moderate (Kappa value = 0.452).

Conclusions: The sensitivity of pepsin IHC staining in laryngeal lesions for diagnosing LPR is satisfactory. The existence of false negative of MII-pH may be the main reason for the low specificity.     

星点设计-效应面法优化pH值响应及线粒体靶向双功能金丝桃苷脂质体的处方及其体外评价

目的 优化线粒体靶向金丝桃苷脂质体（DLD/Hyp-Lip）制备的最佳处方，并研究研究其在胎牛血清中的稳定性及体外释放行为，考察其线粒体靶向性。方法 采用薄膜分散法制备DLD/Hyp-Lip，以包封率和载药量为考察指标进行单因素实验，考察磷脂总量与金丝桃苷（hyperoside，Hyp）用量比、二硬脂酰磷脂酰乙醇胺-聚乙二醇（DSPE-PEG）与DLD用量比等条件对DLD/Hyp-Lip的影响，结合星点设计-效应面法优化DLD/Hyp-Lip处方。使用透射电子显微镜和粒径仪观察测定脂质体粒子外观、平均粒径和Zeta电位，采用血清稳定性实验和体外释药、线粒体靶向性对该载药系统进行评价。结果 DLD/Hyp-Lip最佳处方为磷脂总量和金丝桃苷用量比为12.50：1，磷脂总量与胆固醇用量比为6.00：1，DSPE-PEG与DLD用量比为3：5；测得金丝桃苷包封率为（95.57±0.56）%，载药量为（8.55±0.57）%。所制备的DLD/Hyp-Lip外观良好，平均粒径为（124.9±3.4）nm，Zeta电位为（-6.2±1.9）mV；在胎牛血清中性状稳定，在体外释放介质中24 h累积释放量达到40%。线粒体靶向实验表明DLD/Hyp-Lip可以促进药物聚集在线粒体部位。结论 采用此方法能够精准有效的优化DLD/Hyp-Lip的制备工艺，该方法操作简单方便，可以用于DLD/Hyp-Lip制备与处方的优化，制备的DLD/Hyp-Lip包封率高，粒径小，分布均匀，且具有良好的缓释作用，为DLD/Hyp-Lip的进一步体内研究奠定了基础。载金丝桃苷的DLD/Hyp-Lip具有良好的肝癌细胞线粒体靶向性，是一种潜在高效的肝癌细胞线粒体靶向给药系统。     

重酒石酸长春瑞滨长循环脂质体的制备与表征

目的采用pH梯度法制备重酒石酸长春瑞滨长循环脂质体并进行表征。方法以粒径为指标,考察水化温度和挤出次数对空白脂质体粒径的影响;以粒径及包封率为指标,考察孵化温度和孵化时间对载药脂质体粒径和包封率的影响。并采用Malvern粒度仪测定脂质体的粒径分布、多分散系数及Zeta电位,透射电镜考察其形态,并考察脂质体稳定性。结果重酒石酸长春瑞滨长循环脂质体粒径（96.4±27.2） nm,多分散系数（0.162±0.042）,Zeta电位（－26.7±3.5） mV;透射电镜显示脂质体粒径均一,成单层膜球状分布;长期稳定性研究显示,脂质体在5 ℃条件下放置3个月稳定。结论pH梯度法可以用于重酒石酸长春瑞滨长循环脂质体的制备。     

不同部位菌斑pH的动态变化及其与唾液的关系

目的：测定口腔不同部位菌斑在进食后pH的动态变化，探讨不同部位菌斑产酸力的差异及唾液在产酸代谢过程中的作用。方法：采用微型pH电极接触法原位测试患龋状况不同者上、下颌，健康部位与龋坏部位菌斑及唾液pH在含漱糖液前后1h内的变化。结果：不同部位菌斑pH在漱糖后均呈先下降后上升的趋势；患龋状况不同者健康部位菌斑pH在用糖后的变化无统计学差异；上颌菌斑pH变化幅度均较下颌明显；龋洞内菌斑pH变化幅度均较健康部位明显；唾液与菌斑pH间无明显相关性。结论：口腔不同部位菌斑内的产酸代谢活动存在差异，这可能主要与不同部位唾液对糖的清除有关；而唾液的缓冲作用对菌斑的产酸代谢无明显影响。