Mathematical modeling of molecular diffusion through mucus

The rate of molecular transport through the mucus gel can be an important determinant of efficacy for therapeutic agents delivered by oral, intranasal, intravaginal/rectal, and intraocular routes. Transport through mucus can be described by mathematical models based on principles of physical chemistry and known characteristics of the mucus gel, its constituents, and of the drug itself. In this paper, we review mathematical models of molecular diffusion in mucus, as well as the techniques commonly used to measure diffusion of solutes in the mucus gel, mucus gel mimics, and mucosal epithelia.     

An electron microscopic study of Aujeszky's disease

Summary Sixteen calves were killed at intervals during the course of the disease from 48 h onwards after subcutaneous infection with Aujeszky's disease virus. Ultrastructural changes were evident in the spinal ganglia from 84 h post-inoculation and the intercostal nerves from 96 h post-inoculation. The cytopathic changes in the spinal ganglia consisted of neuronal degeneration, neuronophagia, Schwann cell degeneration and cellular infiltration. The neuronophagic nodule was invariably contained within an intact sheath of satellite cells. Changes in the intercostal nerves were less dramatic but cellular infiltration was frequently seen and occasional Schwann cells were degenerate. In the terminal stages of the disease demyelination was rarely observed. In the ganglion virus was invariably seen in degenerating neurons and occasionally in Schwann cells and monocytes. Satellite cells were rarely infected even when ensheathing an infected neuron. Extra-cellular virus was not observed in ganglia or nerves. Schwann cells and monocytes in the nerves were occasionally infected. Virus particles were seen in the axoplasm both in the ganglion and in the entire length of the nerve. The particles in the axoplasm varied in morphology; thus unenveloped and enveloped particles, and particles in the process of acquiring an envelope were recognised. It was concluded that the neural pathway of Aujeszky's disease virus is probablyvia the axoplasm.     

清洁磨损钛微粒对巨噬细胞释放破骨性细胞因子的影响

目的:探讨人工关节磨损清洁钛微粒的大小及不同微粒-细胞比对巨噬细胞释放破骨性细胞因子:肿瘤坏死因子-α(TNF-α)、白细胞介素-1(IL-1)、白细胞介素-6(IL-6)和前列腺素(PGE2)的影响。方法:清洁钛微粒按直径大小分为(0.35±0.09),(1.5±0.38),(6.25±2.13)μm组,分别以微粒-细胞比1:1,10:1,100:1,500:1,1000:1与巨噬细胞联合培养,用酶联免疫吸附法(ELISA)检测细胞培养上清液TNF-α、IL-1、IL-6、PGE2含量。结果:各组清洁钛微粒在微粒-细胞比10:1时,巨噬细胞释放TNF-α较对照组显著增高(P<0.05),500:1时释放TNF-α达到高峰,1000:1时分泌量下降。(0.35±0.09)μm清洁钛微粒组较(1.5±0.38)μm和(6.25±2.13)μm清洁钛微粒组,(1.50±0.38)μm清洁钛微粒组较(6.25±2.13)μm清洁钛微粒组,分别在微粒-细胞比10:1,100:1,500:1时,巨噬细胞释放更多TNF-α,具有统计学差异(P<0.05)。各组间IL-1、IL-6含量无显著性差异(P>0.05)。微粒-细胞比500:1,1000:1时,PGE2含量显著增高(P<0.01),巨噬细胞存活率显著下降(P<0.01)。结论:清洁磨损钛微粒大小及微粒-细胞比是决定磨损微粒生物细胞学反应的重要参量。磨损微粒越小,微粒-细胞比越高,生物细胞学毒性越大,能刺激巨噬细胞释放更多破骨性细胞因子TNF-α。清洁钛微粒本身并不能刺激巨噬细胞释放IL-1、IL-6、PGE2。     

肾综合征出血热病毒气溶胶的物理稳定性实验研究

本文采用荧光素钠正常鼠脑悬液做模拟示踪物质，对肾综合征出血热病毒气溶胶在空气中的物理稳定性进行了测定，并与其生物稳定性做了比较。结果表明：病毒气溶胶的粒子大小在１ｕｍ左右，它随气溶胶的胶龄增长而减少，且其分散度变窄。初始气溶胶的物理回收率及其各胶龄的物理存留率均明显地高于它的生物回收率和生物存活率。本文还就肾综合征出血热病毒气溶胶的物理稳定性和生物稳定性，对本病空气传播的影响进行了讨论。     

不同粒径大气颗粒物中金属元素含量及其免疫毒性研究

运用ＤＦＪ－１型五段分级采样器采集太原市空气中颗粒物。用原子吸收分光光度法测定不同粒径颗粒物上六种金属元素Ｐｂ、Ｍｎ、Ｎｉ、Ｃｏ、Ａｓ、Ｚｎ的含量。用淋巴细胞转化功能、白介素２（ＩＬ－２）活性和Ｔ细胞亚群分析观察不同粒径的颗粒物提取液对小鼠的免疫毒性。结果表明Ｐｂ、Ｍｎ、Ａｓ、Ｚｎ含量较高，Ｎｉ、Ｃｏ含量较低。７０％￣８０％的Ｐｂ、Ｎｉ、Ａｓ、Ｚｎ富集在≤２．０μｍ颗粒的免疫毒性较强。     

健脾祛湿颗粒口服配合消炎止痒洗剂湿敷治疗湿疹的疗效观察

目的 观察健脾祛湿颗粒口服配合消炎止痒洗剂湿敷治疗湿疹的临床疗效.方法 将90例湿疹患者随机分为治疗组和对照组,各45例,治疗组采用本科自制的健脾祛湿颗粒,每天一剂,分早晚两次温水冲服,配合消炎止痒洗剂：将20 g药粉加2000 ml温开水浸泡20 min,待冷却至室温后,将5～6层纱布浸渍于药液中片刻后取出,拧至不滴水后湿敷患处,每次20 min,每天2～3次.对照组采用莫匹罗星软膏联合糠酸莫米松乳膏外用治疗.两组均治疗30天,观察两组治疗前后瘙痒程度、皮疹形态、皮疹面积积分及总积分,并比较两组临床疗效和治疗期间出现的不良反应.结果 治疗后,治疗组的皮疹形态、皮疹面积积分均低于对照组,经比较差异有统计学意义（P＜ 0.05,P＜ 0.01）,对照组瘙痒程度积分高于治疗组,经比较差异有统计学意义（P＜0.05）,而两组的总积分比较差异无统计学意义（P＞ 0.05）;治疗组总有效率为86.7％,对照组为77.7％,经Riddt分析,差异无统计学意义（u=-1.590,P＞ 0.05）;治疗组中总共有3例出现皮肤灼痛感及色素沉着不良反应,而对照组出现8例.结论 健脾祛湿颗粒口服配合消炎止痒洗剂湿敷治疗湿疹与莫匹罗星软膏联合糠酸莫米松乳膏外用治疗相比,总体疗效相当,但前者在改善患者皮疹形态和皮疹面积方面优于后者,且不良反应相对较少,不失为临床上治疗湿疹的一种可选方案.     

沉降法测定大气真菌粒子含量的探讨

本工作用 ANDERSEN 生物粒子采样器法和平皿沉降法在北京西单对大气真菌粒子的含量进行了一年的对比观测实验。结果表明,在同一次大气真菌粒子沉降量的采样中,放置的采样皿数对测定结果没有明显影响。大气真菌粒子沉降量与大气真菌粒子含量呈非常显著的正相关关系。由本实验得出的关系式能较准确、简便的计算大气真菌粒子的含量。     

加味泻白颗粒薄层色谱鉴别方法改进

目的：改进加味泻白颗粒中菝契皂苷元的薄层色谱鉴别方法。方法：采用薄层色谱进行鉴别分析。结果：改进了菝契皂苷元的薄层色谱鉴别方法。结论：薄层色谱鉴别方法快速简便、稳定,专属性好。     

Acute and subchronic oral toxicity studies in rats with nanoscale and pigment grade titanium dioxide particles

Data generated using standardized testing protocols for toxicity studies generally provide reproducible and reliable results for establishing safe levels and formulating risk assessments. The findings of three OECD guideline-type oral toxicity studies of different duration in rats are summarized in this publication; each study evaluated different titanium dioxide (TiO₂) particles of varying sizes and surface coatings. Moreover, each study finding demonstrated an absence of any TiO₂ -related hazards. To briefly summarize the findings: 1) In a subchronic 90-day study (OECD TG 408), groups of young adult male and female rats were dosed with rutile-type, surface-coated pigment-grade TiO₂ test particles (d₅₀ = 145 nm − 21% nanoparticles by particle number criteria) by oral gavage for 90 days. The no-adverse-effect level (NOAEL) for both male and female rats in this study was 1000 mg/kg bw/day, the highest dose tested. The NOAEL was determined based on a lack of TiO₂ particle-related adverse effects on any in-life, clinical pathology, or anatomic/microscopic pathology parameters; 2) In a 28-day repeated-dose oral toxicity study (OECD TG 407), groups of young adult male rats were administered daily doses of two rutile-type, uncoated, pigment-grade TiO₂ test particles (d₅₀ = 173 nm by number) by daily oral gavage at a dose of 24,000 mg/kg bw/day. There were no adverse effects measured during or following the end of the exposure period; and the NOAEL was determined to be 24,000 mg/kg bw/day; 3) In an acute oral toxicity study (OECD TG 425), female rats were administered a single oral exposure of surface-treated rutile/anatase nanoscale TiO₂ particles (d₅₀ = 73 nm by number) with doses up to 5000 mg/kg and evaluated over a 14-day post-exposure period. Under the conditions of this study, the oral LD₅₀ for the test substance was >5000 mg/kg bw. In summary, the results from these three toxicity studies – each with different TiO₂ particulate-types, demonstrated an absence of adverse toxicological effects. Apart from reporting the findings of these three studies, this publication also focuses on additional critical issues associated with particle and nanotoxicology studies. First, describing the detailed methodology requirements and rigor upon which the standardized OECD 408 guideline subchronic oral toxicity studies are conducted. Moreover, an attempt is made to reconcile the complex issue of particle size distribution as it relates to measurements of nanoscale and pigment-grade TiO₂ particles. Clearly this has been a confusing issue and often misrepresented in the media and the scientific literature. It is clear that the particle-size distribution for pigment-grade TiO₂, contains a small (“tail”) component of nanoscale particles (i.e., 21% by particle number and <1% by weight in the test material used in the 90-day study). However, this robust particle characterization finding should not be confused with mislabeling the test materials as exclusively in the nanoscale range. Moreover, based upon the findings presented herein, there appears to be no significant oral toxicity impact contributed by the nanoscale component of the TiO₂ Test Material sample in the 90-day study. Finally, it seems reasonable to conclude that the study findings should be considered for read-across purposes to food-grade TiO₂ particles (e.g., E171), as the physicochemical characteristics are quite similar.     

小儿肺热咳喘颗粒清热解毒、止咳平喘作用研究

目的 研究小儿肺热咳喘颗粒（XFKP）清热解毒、止咳平喘作用。方法 采用牛奶致热家兔模型观察XFKP的解热作用;制备脂多糖（LPS）肺炎小鼠模型,观察XFKP对支气管肺泡灌洗液中超氧化物歧化酶（SOD）、髓过氧化物酶（MPO）活性及炎症细胞的积聚的影响;采用小鼠氨水、豚鼠磷酸组胺诱咳引喘模型,观察XFKP的止咳平喘作用。结果 与对照组比较,高、中剂量XFKP能够显著降低发热家兔体温（P<0.05）;高、中剂量XFKP明显降低肺炎模型小鼠肺内积水量和肺泡中白细胞总数、淋巴细胞数,且高剂量组能显著抑制MPO活性（P<0.05、0.01）;高、中剂量XFKP组能够显著地延长小鼠咳嗽潜伏期,减少咳嗽次数,延长豚鼠引喘潜伏期（P<0.05、0.01）。结论 小儿肺热咳喘颗粒具有显著的清热解毒、止咳平喘作用。