左旋肉碱修饰的壳聚糖-硬脂酸协载槲皮素口服紫杉醇纳米胶束的制备、表征及在体肠循环研究

目的 制备左旋肉碱修饰的壳聚糖-硬脂酸（LC-SA/CS-SA）纳米胶束，包载紫杉醇（PTX）且协载槲皮素，考察胶束特性，并以大鼠在体肠循环评估给药系统对PTX口服吸收的促进作用。方法 将硬脂酸（SA）通过酰胺化反应接枝于壳聚糖（CS），形成共聚物CS-SA；采用核磁共振H谱、红外光谱鉴定产物结构；以PTX为主药，槲皮素为辅药，采用激光粒径分析、Zeta电位分析和HPLC分析分别考察了胶束的粒径、Zeta电位、载药量、包封率；透射电子显微镜观察胶束形貌；芘荧光探针法测定LC-SA/CS-SA胶束的临界胶束浓度（critical micelle concentration，CMC）；透析袋法考察胶束的体外释放行为；大鼠在体肠吸收实验评估载药胶束的促吸收作用。结果 红外与核磁结果表明SA通过酰胺键接枝于CS；协载槲皮素的LC-SA/CS-SA载PTX胶束呈类球形，粒径为（148.3±1.7）nm，多分散系数（PDI）为0.16±0.07，Zeta电位为（24.600±0.167）mV，CMC为14.31 μg/mL；体外释放结果表明，与市售紫杉醇注射剂相比，协载槲皮素的LC-SA/CS-SA载PTX胶束、LC-SA/CS-SA载PTX胶束具有明显缓释效应；大鼠在体肠吸收实验表明，协载槲皮素的LC-SA/CS-SA胶束对载药PTX的胃肠吸收具有显著促进作用。结论 构建的协载槲皮素的LC-SA/CS-SA载PTX胶束性能优良，促进了PTX的大鼠肠吸收，具有增强药物口服吸收潜力。     

基于药动学与药效学相关联的养阴通脑颗粒主要有效部位正交配伍研究

目的探讨养阴通脑颗粒主要有效部位(总生物碱、总黄酮、总皂苷、总酚酸)配伍后在脑缺血再灌注模型大鼠体内药物浓度及其药动学与药效学变化。方法采用正交试验法组成上述主要有效部位用量配比不同的9个组方,供脑缺血再灌注模型大鼠ig给药,高效液相色谱-二极管阵列检测器(HPLC-DAD)测定不同时间点血浆中的葛根素、阿魏酸和川芎嗪血浆药物浓度。DAS 3.2.6软件以非房室模型拟合药动学参数,并运用总量统计矩法和综合评分法对整体药动学特征进行评价。同时采用酶联免疫吸附测定(ELISA)法测定大鼠血浆中超氧化物歧化酶(SOD)和过氧化氢酶(CAT)的含量。最后进行药动学-药效学(PK-PD)模型研究,获得各药物浓度与药效之间的定量方程。结果葛根素、阿魏酸和川芎嗪在模型大鼠体内的药动学特征有所差异。总量统计矩和综合评分研究表明不同配伍对总量零阶矩、总量平均滞留时间、综合评分等参数影响不一。主要有效部位正交配伍给药后,一定程度上会抑制脑缺血再灌注大鼠血浆中SOD和CAT的降低。各PK-PD模型均采用Sigmoid-Emax模型,拟合结果与实测数据之间相关性良好,R值均大于0.85。结论养阴通脑颗粒主要有效部位配伍对模型大鼠体内的药动学行为和抗氧化指标具有一定影响;中药复方多成分药物代谢动力学可采用总量统计矩和综合评分法进行研究;PK-PD结合模型可用于中药复方多成分药动学与药效学之间相关性的评价与预测。     

Dual-Stage Picolinic Acid-Derived Inhibitors of Toxoplasma gondii

Toxoplasma gondii causes a prevalent human infection for which only the acute stage has an FDA-approved therapy. To find inhibitors of both the acute stage parasites and the persistent cyst stage that causes a chronic infection, we repurposed a compound library containing known inhibitors of parasitic hexokinase, the first step in the glycolysis pathway, along with a larger collection of new structural derivatives. The focused screen of 22 compounds showed a 77% hit rate (>50% multistage inhibition) and revealed a series of aminobenzamide-linked picolinic acids with submicromolar potency against both T. gondii parasite forms. Picolinic acid 23, designed from an antiparasitic benzamidobenzoic acid class with challenging ADME properties, showed 60-fold-enhanced solubility, a moderate LogD_7.4, and a 30% improvement in microsomal stability. Furthermore, isotopically labeled glucose tracing revealed that picolinic acid 23 does not function by hexokinase inhibition. Thus, we report a new probe scaffold to interrogate dual-stage inhibition of T. gondii.     

Consensus summary report for CEPI/BC March 12–13, 2020 meeting: Assessment of risk of disease enhancement with COVID-19 vaccines

A novel coronavirus (CoV), Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), emerged in late 2019 in Wuhan, China and has since spread as a global pandemic. Safe and effective vaccines are thus urgently needed to reduce the significant morbidity and mortality of Coronavirus Disease 2019 (COVID-19) disease and ease the major economic impact. There has been an unprecedented rapid response by vaccine developers with now over one hundred vaccine candidates in development and at least six having reached clinical trials. However, a major challenge during rapid development is to avoid safety issues both by thoughtful vaccine design and by thorough evaluation in a timely manner. A syndrome of “disease enhancement” has been reported in the past for a few viral vaccines where those immunized suffered increased severity or death when they later encountered the virus or were found to have an increased frequency of infection. Animal models allowed scientists to determine the underlying mechanism for the former in the case of Respiratory syncytial virus (RSV) vaccine and have been utilized to design and screen new RSV vaccine candidates. Because some Middle East respiratory syndrome (MERS) and SARS-CoV-1 vaccines have shown evidence of disease enhancement in some animal models, this is a particular concern for SARS-CoV-2 vaccines. To address this challenge, the Coalition for Epidemic Preparedness Innovations (CEPI) and the Brighton Collaboration (BC) Safety Platform for Emergency vACcines (SPEAC) convened a scientific working meeting on March 12 and 13, 2020 of experts in the field of vaccine immunology and coronaviruses to consider what vaccine designs could reduce safety concerns and how animal models and immunological assessments in early clinical trials can help to assess the risk. This report summarizes the evidence presented and provides considerations for safety assessment of COVID-19 vaccine candidates in accelerated vaccine development.     

聚乳酸羟基乙酸载全氟溴辛烷-四氧化三铁包金纳米粒子双模态成像与光热治疗的体外研究

目的制备具有表面金壳以聚乳酸羟基乙酸(PLGA)为载体包载全氟溴辛烷(PFOB)和四氧化三铁(SPIOs)的纳米粒子,用于探究其体外超声显像和磁共振成像能力和光热杀伤肿瘤细胞效果。方法采用单乳化水包油(O/W)溶剂挥发法制备PFOB-SPIOs@PLGA纳米粒子,金种子生长法形成纳米粒子表面金壳制备;对其进行表征;通过CCK-8法评估纳米粒子的细胞毒性情况;采用超声和磁共振成像仪器观察纳米粒子的体外成像效果;近红外激光照射纳米粒子溶液观测升温效果;AM单染在激光共聚焦下观察光热杀伤肿瘤细胞效果。结果成功制备了PFOB-SPIOs@PLGA@Au纳米粒子,纳米粒子平均粒径(347±65.8)nm,粒径均一,分散性好;磁共振测得r2值为(465.23±30.39)mM-1s-1,具有体外磁共振T2成像效果;具有体外超声成像效果;近红外激光照射纳米粒子溶液10min最高温度可达45.2℃;CCK-8法检测纳米粒子对各组细胞存活率无明显影响。结论成功制备了粒径均一的PFOB-SPIOs@PLGA@Au纳米粒子,该纳米粒子具有较好的超声和磁共振T2体外成像效果和体外升温效果,且无明显细胞毒性。     

Rhinofilling with hyaluronic acid thought as a cartilage graft

IntroductionThere is great demand for nonsurgical aesthetic procedures. In this case series, the authors describe their stepwise technique of injecting hyaluronic acid (HA) into the nose to yield pleasing, stable results.Case seriesA total of 148 patients underwent minimally invasive rhinoplasty by injection of HA filler. Anatomic contraindications for the procedure were a large dorsal hump, extreme tip projection, or excessive nasal deviation. HA injections were made in a specific order to reshape and stabilize the nose; the surgical plan was conceptually similar to placement of cartilage grafts. Patients indicated their satisfaction with the surgical results on a visual analog scale. Immediately after the procedure, all patients had transient redness and slight swelling at the injection site; this resolved spontaneously by 24 h posttreatment. Vascular impairment developed in 1 patient and was managed with hyaluronidase. In general, patients expressed a high level of satisfaction. Thirty-two patients returned for a “touch-up” filler injection 1 year posttreatment.DiscussionNasal reshaping by HA injection can be carried out quickly, safely, and effectively with minimal patient discomfort or downtime. Care must be given to select patients who are indicated for this procedure, and meticulous pretreatment planning is necessary.     

超分子水杨酸治疗痤疮的效果及对皮肤屏障的影响

目的:观察超分子水杨酸对于痤疮的疗效及皮肤屏障的影响。方法:采用随机对照实验。选取痤疮患者40例,随机分为实验组和对照组,每组20例。实验组:给予30%超分子水杨酸换肤治疗,1周1次并配合外用特护霜,共治疗4次;对照组:仅每日给予特护霜外用。疗程结束4周后随访观察。治疗前及随访时使用CK无创皮肤检测仪检测两组患者面部皮肤生理指标,计数面部皮损。使用VISIA皮肤分析仪拍照留存。结果:实验组总有效率90%,对照组总有效率15%,两组比较有显著性差异(P<0.05)。同治疗前相比,实验组治疗后经皮水分丢失量(TEWL)、红斑值、角质层含水量及p H值均有改善,差异均有统计学意义(P<0.05)。与对照组比较,实验组治疗后TEWL、角质层含水量及p H值均有改善,差异均有统计学意义(P<0.05)。两组患者均未出现色素沉着、瘢痕等不良反应。结论:超分子水杨酸治疗痤疮疗效确切,同时具有修复皮肤屏障的作用。