Surface‒Aerosol Stability and Pathogenicity of Diverse Middle East Respiratory Syndrome Coronavirus Strains, 2012‒2018

Middle East respiratory syndrome coronavirus (MERS-CoV) infects humans and dromedary camels and is responsible for an ongoing outbreak of severe respiratory illness in humans in the Middle East. Although some mutations found in camel-derived MERS-CoV strains have been characterized, most natural variation found across MERS-CoV isolates remains unstudied. We report on the environmental stability, replication kinetics, and pathogenicity of several diverse isolates of MERS-CoV, as well as isolates of severe acute respiratory syndrome coronavirus 2, to serve as a basis of comparison with other stability studies. Although most MERS-CoV isolates had similar stability and pathogenicity in our experiments, the camel-derived isolate C/KSA/13 had reduced surface stability, and another camel isolate, C/BF/15, had reduced pathogenicity in a small animal model. These results suggest that although betacoronaviruses might have similar environmental stability profiles, individual variation can influence this phenotype, underscoring the need for continual global viral surveillance.     

SARS-CoV-2 Aerosol Exhaled by Experimentally Infected Cynomolgus Monkeys

We analyzed size of severe acute respiratory coronavirus 2 (SARS-CoV-2) aerosol particles shed by experimentally infected cynomolgus monkeys. Most exhaled particles were small, and virus was mainly released early during infection. By postinfection day 6, no virus was detected in breath, but air in the isolator contained large quantities of aerosolized virus.     

混合模式色谱柱全水相测定阿仑膦酸钠片的含量和有关物质

目的 建立一种混合模式色谱柱联用电雾式检测器测定阿仑膦酸钠片的含量和有关物质的方法。方法 采用Acclaim Trinity P2色谱柱（2.1 mm×100 mm,3 μm）,柱温35℃,以水（A）-100 mmol·L^-1甲酸铵溶液（用甲酸调至pH 3.3,B）为流动相进行梯度洗脱（0~4 min,20%→50% B;4~6 min,50%→40% B;6~8 min,40%→20% B）,流速为0.3 mL·min^-1,进样量为20 μL;采用电雾式检测器测定,雾化温度为50℃,采样频率为5 Hz,过滤常数为3.6 s。结果 阿仑膦酸钠在0.70~1.40 mg·mL^-1内线性良好（r²=0.999 2）,方法重复性的RSD为0.53%,平均加样回收率（n=9）为99.8%（RSD=1.25%）;有关物质测定项下,主成分阿仑膦酸钠,杂质磷酸盐、亚磷酸盐及4-氨基丁酸分别在19.04~76.16,3.95~49.38,3.97~49.69,3.94~49.23 μg·mL^-1内线性良好（r²>0.998）,且各杂质的校正因子为0.67,0.56,0.55,各杂质定量限约为主成分浓度的0.05%,杂质测定方法的平均回收率（n=9）分别为86.2%,85.4%,91.0%,且RSD<2%;3家企业生产的阿仑膦酸钠片剂中阿仑膦酸的标示含量分别为92.0%,91.5%,95.2%,各杂质含量均小于中国药典阿仑膦酸钠项下规定的限度0.5%。结论 该方法操作简便,灵敏度和准确性较高,可用于阿仑膦酸钠片的含量测定和有关物质检查。     

两种测定布地奈德气雾剂雾粒分布方法的比较

分别采用中国药典2010年版二级碰撞器法和美国药典35版药用多级碰撞器法(NGI)测定了4批布地奈德气雾剂的雾粒分布,并比较了两种方法的测定结果.结果表明,两种方法测得的雾粒分布基本一致.NGI法更能模拟布地奈德气雾剂在呼吸道中每个部位的沉积情况,获得的空气动力学粒径参数与人类的呼吸道系统一致.为了更好地控制布地奈德气雾剂的质量,有必要在布地奈德气雾剂质量标准中增订NGI法进行雾粒分布检查.     

Effect of exposure to fentanyl aerosol in mice on breathing pattern and respiratory variables

The breathing pattern of mice that were exposed to fentanyl aerosol was studied (2.7, 5.7, 6.0, 10.0, and 23.6 μg/m³; for 1 hour), using dimethyl sulfoxide as a vehicle. This study was conducted in a head-only exposure assembly. Body plethysmographs connected to a volumetric pressure transducer were used to capture the respiratory signals, and an on-line computer program capable of recognizing the changes in the breathing pattern was used for monitoring the respiratory pattern. The response of mice to fentanyl exposure was found to be concentration dependent. A lower concentration (2.7 μg/m³) showed fast recovery and no mortality, while 100% mortality was observed at a higher concentration (23.6 μg/m³). No sensory, pulmonary irritation, and airway limitation in mice was observed, and death occurred probably due to respiratory depression. The concentration that decreased 50% of the respiratory frequency (RD₅₀) was estimated to be 6.4 μg/m³. The extrapolated human threshold limit value, calculated from the RD₅₀ value, was found to be 0.192 μg/m³. The concentration that caused 50% mortality in exposed mice (LC₅₀) was estimated to be 8.8 μg/m³. This study shows that aerosolized fentanyl does not cause sensory and pulmonary irritation, and since the RD₅₀ and LC₅₀ are very close with a low safety margin, this type of sedative should not be used as an incapacitating agent.     

Evaluation of cerium oxide and cerium oxide based fuel additive safety on organotypic cultures of lung slices

Among the various technological proposals under consideration to limit diesel exhaust particles (DEP) emissions, the use of a particulate filter in conjunction with a fuel-borne catalyst is currently the primary focus and likely to be introduced over the coming years. One specific catalyst is a cerium-based compound Envirox? developed by Oxonica (Kidlington, UK) and used as a fuel additive to reduce particulate matter (PM) emissions from diesel engines. Prior to any commercialization it is necessary to undertake an assessment of any potential adverse health effects resulting from exposure to cerium oxide particles especially via the inhalation route, i.e., on the lung. Since the composition of engine exhaust emissions from additized fuel might be different to those emissions from un-additized diesel fuel, the second phase of the current investigation compared the potential biological impact of engine emissions from cerium oxide additized fuel to that of a reference fuel. An experimental procedure developed in our laboratory using an organotypic culture of lung slices was used. Biological endpoints were chosen in order to evaluate cell viability (ATP, intracellular GSH), pro-inflammatory reaction (TNF alpha) and anti-oxidant enzyme activity (total GPx, Mn SOD, catalase). No impact of nanoparticulate cerium oxide aerosol on lung tissue biological parameters was observed with one exception, an increased catalase activity which was not associated with a concomitant loss in cell viability. It is therefore concluded, on the basis of this study and from the prospective potential exposure to cerium oxide, that a very low prospective risk is associated with the expected dissemination of cerium oxide in the atmosphere. Concerning the biological impact of Envirox? additized-diesel fuel, the observed effects are of very limited incidence in that the observed trend on organotypic culture viability and TNF alpha is beneficial, while a limited oxidant activity is observed through catalase induction. Emissions from diesel fuel additized with the tested cerium oxide catalyst do not induce any increase in the known adverse biological effects caused by diesel fuel engine emissions alone in our experimental set-up.     

Inhalation delivery dramatically improves the efficacy of topotecan for the treatment of local and distant lung cancer

Topotecan is potent anti-cancer drug approved for various malignancies but hematopoietic toxicities undermine its wider application and use of its most effective dose. This study aims to improve these limitations through inhalation-delivery. The pharmacokinetics, efficacy, and toxicity of 2–5 times lower inhalation doses of topotecan dry-powder were compared with the standard intravenous (IV) delivery once/twice-a-week. Human-derived EGFR-mutant (H1975), KRAS-mutant (A549), and EGFR/KRAS wild-type (H358) orthotopic and distant lung tumors were evaluated in murine models. Inhalation of 1 mg/kg topotecan significantly improved the half-life and drug exposure (area under the curve, AUC) compared to 5 mg/kg via IV-delivery. AUCs (h*ng/mL) for inhaled/IV topotecan in plasma, lung, liver, and brain were, 831/888, 60,000/1080, 8380/4000, and 297/15, respectively; while the half-life was also greatly increased in these tissues. The average lung tumor burden of H358-derived tumors was reduced from 15.0 g to 8.4 g (44%) in rats treated once-a-week with 2 mg/kg IV and 1.8 g (88%) with 1 mg/kg inhaled topotecan, corroborating previous findings using A549- and H1975-derived orthotopic lung tumors. Importantly, inhaled topotecan showed superior efficacy in suppressing lung tumors at distant sites. The growth of H1975- and H358-derived subcutaneous xenografts were completely arrested and A549-derived tumors were significantly reduced in mice treated twice-a-week with 1 mg/kg inhaled topotecan compared to a minor (H1975 and H358) or no reduction (A549) with twice-a-week 5 mg/kg IV topotecan.     

孟鲁司特钠联合异丙托溴铵＋布地奈德混悬液雾化吸人治疗儿童感染后咳嗽临床研究

目的观察孟鲁司特钠咀嚼片联合异丙托溴铵＋布地奈德混悬液雾化吸入治疗儿童感染后咳嗽的临床疗效。方法选取2012年1月-2013年10月收治的PIC患儿100例,按随机数字表法分为对照组和观察组各50例,对照组给予孟鲁司特钠咀嚼片治疗,连续服用10d;观察组在对照组基础上,给予吸入用复方异丙托溴铵溶液1．25ml＋布地奈德混悬液1ml,连用10d。比较两组的临床疗效和峰流速值。结果总有效率对照组62．0％,观察组92．0％,两组比较差异有统计学意义（X^2=12．705,P〈0．05）。治疗后两组患者PEFR较治疗前均有显著改善,对照组（72．95±5．69）L／Min,观察组（81．24±4．01）L／Min,两组比较差异有统计学意义（t=8．421,P〈0．05）。结论孟鲁司特钠咀嚼片联合异丙托溴铵＋布地奈德混悬液雾化吸人治疗儿童PIC,临床疗效显著,值得临床推广应用。     

Aerodynamical, Immunological and Pharmacological Properties of the Anticancer Antibody Cetuximab Following Nebulization

Purpose

Despite an increasing interest in the use of inhalation for local delivery of molecules for respiratory diseases and systemic disorders, methods to deliver therapy through airways has received little attention for lung cancer treatment. However, inhalation of anticancer drugs is an attractive alternative route to systemic administration which results in limited concentration of the medication in the lungs, and triggers whole-body toxicity. In this study, we investigated the feasibility of nebulization for therapeutic antibodies, a new class of fully-approved anticancer drugs in oncology medicine.

Materials and methods

Cetuximab, a chimeric IgG1 targeting the epidermal growth factor receptor (EGFR), was nebulized using three types of delivery devices: a jet nebulizer PARI LC+®, a mesh nebulizer AeronebPro® and an ultrasonic nebulizer SYST’AM® LS290. Aerosol size distribution was measured using a cascade impactor and aerosol droplets were observed under optical microscopy. The immunological and pharmacological properties of cetuximab were evaluated following nebulization using A431 cells.

Results

The aerosol particle clouds generated with the three nebulizers displayed similar aerodynamical characteristics, but the IgG formed aggregates in liquid phase following nebulization with both the jet and ultrasonic devices. Flow cytometry analyses and assays of EGFR-phosphorylation and cell growth inhibitions on A431 demonstrated that both the mesh and the jet nebulizers preserved the binding affinity to EGFR and the inhibitory activities of cetuximab.

Conclusions

Altogether, our results indicate that cetuximab resists the physical constraints of nebulization. Thus, airway delivery represents a promising alternative to systemic administration for local delivery of therapeutic antibodies in lung cancer treatment.     

Bricasol气雾剂治疗支气管哮喘临床及即时肺功能研究

目的 研究应用Bricasol气雾剂后肺功能的改善情况及治疗效果。方法 选择支气管哮喘发作期患者32例，其中男16例，女16例，分男、女两组观察。患者到实验室后先休息10～15min，然后吸入Bricasol气雾剂共两喷，间隔半分钟，剂量共0．5mg，观察治疗前和治疗后1、5、15min的肺功能变化。结果 男、女两组吸药后1、5、15minFEV1.0均值；V75吸药后5、15min均值；PEFR女吸药后1、5、15min、男吸药后5、15min均值；FVC女吸药后1、5、15min均值均较吸药前明显增加或极明显增加。所有观察对象均于吸药后5min憋喘症状明显减轻，听诊哮鸣音减少，15min憋喘症状改善最为明显。结论 吸入Bricasol气雾剂后，支气管哮喘患者肺功能明显改善，显效迅速，疗效好，是较理想的支气管舒张剂。