1,2-丙二醇体内外安全性实验研究

目的 从体内和体外分别考察1,2-丙二醇气管内雾化给药局部刺激性、体外溶血性和细胞毒性,初步评价1,2-丙二醇吸入给药安全性。方法 取大鼠,采用气管内雾化给药方式给予30% 1,2-丙二醇200 μL,连续5 d,评价1,2-丙二醇吸入给药对肺部的局部刺激性;采用体外试管法肉眼观察和紫外分光光度计法计算溶血率考察1,2-丙二醇的溶血性;采用MTT法研究1,2-丙二醇对人肺腺癌细胞A549、人支气管上皮细胞16HBE、大鼠气管上皮细胞RTE的不良反应,分别计算IC₅₀值。结果 1,2-丙二醇气管内雾化给药后,动物出现极轻度的血管壁周围水肿,极轻度到轻度的肺脏局部支气管内炎症细胞浸润,溶剂对照出现极轻度到轻度的血管壁周围水肿。当1,2-丙二醇浓度≥50%,溶血试验肉眼观察发现,温育1 h上层略偏红色,温育时间延长,颜色略加深,3 h温育结束,发生溶血,但未见凝聚现象;采用紫外分光光度计法计算溶血率均>5%,均有溶血发生。细胞毒性试验中,1,2-丙二醇体积分数在0.12%~10%,对A549、16HBE及RTE的细胞不良反应存在一定的量效关系,相关系数R²值分别为0.986,0.989,0.993,IC₅₀分别为2.538%,2.015%,1.983%。结论 气管内雾化给予1,2-丙二醇对肺部刺激性较小,肺部耐受性较好。浓度≥50%时,可引起溶血。体积分数达到2%时,1,2-丙二醇对A549、16HBE和RTE细胞有显著的不良反应。本研究为1,2-丙二醇吸入途径应用的安全性提供了毒理学数据参考。     

Preparation and evaluation of sustained-release solid dispersions co-loading gastrodin with borneol as an oral brain-targeting enhancer

Borneol is a traditional Chinese medicine that can promote drug absorption from the gastrointestinal tract and distribution to the brain. However, stomach irritation may occur when high doses of borneol are used. In the present work, gastrodin, the main bioactive ingredient of the traditional Chinese drug “Tianma” (Rhizoma Gastrodiae) was used as a model drug to explore reasonable application of borneol. Sustained-release solid dispersions (SRSDs) for co-loading gastrodin and borneol were prepared using ethylcellulose as a sustained release matrix and hydroxy-propyl methylcellulose as a retarder. The dispersion state of drug within the SRSDs was analyzed by using scanning electron microscopy, differential scanning calorimetry, and powder X-ray diffractometry. The results indicated that both gastrodin and borneol were molecularly dispersed in an amorphous form. Assay of in vitro drug release demonstrated that the dissolution profiles of gastrodin and borneol from the SRSDs both fitted the Higuchi model. Subsequently, gastric mucosa irritation and the brain targeting of the SRSDs were evaluated. Compared with the free mixture of gastrodin and borneol, brain targeting of SRSDs was slightly weaker (brain targeting index: 1.83 vs. 2.09), but stomach irritation obviously reduced. Sustained-release technology can be used to reduce stomach irritation caused by borneol while preserving sufficient transport capacity for oral brain-targeting drug delivery.KEY WORDS: Borneol, Gastrodin, Oral drug delivery, Brain-targeting, Gastric mucosa irritation, Sustained-release     

New advances in the pathophysiologic and radiologic basis of the exstrophy spectrum

The exstrophy–epispadias complex is a rare spectrum of anomalies affecting the genitourinary system, anterior abdominal wall, and pelvis. Recent advances in the repair of classic bladder exstrophy (CBE) and cloacal exstrophy (CE) have resulted in significant changes in outcomes of surgical management (including higher continence rate, fewer surgical complications, and better cosmesis) and health-related quality of life in these patients. These noteworthy changes resulted from advances in the pathophysiological and genetic backgrounds of this disease and better radiologic assessment of the three-dimensional anatomy of the bony pelvis and its musculature. A PubMed search was performed with the keyword exstrophy. The resulting literature pertaining to genetics, stem cells, imaging, tissue engineering, epidemiology, and endocrinology was reviewed. The following represents an overview of the advances in basic science understanding and imaging of the exstrophy–epispadias spectrum and discusses their possible and future effects on the management of CBE and CE.     

创伤早期伤口液对体外培养真皮多能干细胞增殖迁移特性的影响

目的 探讨真皮多能干细胞在创伤修复启动中的作用.方法 采用前期建立的技术分离、纯化并扩增真皮多能干细胞、真皮成纤维细胞和血管内皮细胞;利用四唑盐比色试验(MTT法)检测不同时间、不同浓度伤口液对上述细胞的影响.在此基础上,观察伤后1 d伤口液对真皮多能干细胞贴壁力和迁移力等与创伤修复密切相关的指标变化.结果 伤后不同时相不同浓度伤口液对真皮多能干细胞增殖均具有显著刺激作用,但以伤后早期的伤口液作用最为明显.成纤维细胞和血管内皮细胞对伤口液反应均显著弱于真皮多能干细胞.伤口液作用后真皮多能干细胞贴壁力和迁移能力较对照组细胞显著增加.结论 真皮多能干细胞是创伤愈合,特别是创伤修复启动过程中的一种重要的间充质干细胞,对其深入研究有望为阐明创伤修复启动分子机制提供依据.     

First reported case of delayed‐type hypersensitivity reaction to non‐hyaluronic acid Polycaprolactone dermal filler following COVID‐19 vaccination: A case report and a review of the literature

Cases of filler reactions after COVID‐19 vaccination have been reported. Here, we present the first case of delayed‐type reaction (DTR) to non‐hyaluronic acid Polycaprolactone dermal filler after the second dose of Sinopharm COVID‐19 vaccine which was improved with administration of topical and intralesional steroids.     

ArF-excimer laser–induced secondary radiation in photoablation of biological tissue

Secondary radiation, emitted during and after the irradiation of corneal, dermal, and dental tissue by an ArF-excimer laser (193 nm), was qualitatively and quantitatively characterized. Emission of secondary radiation was found in the range of 200–800 nm. The intensity of secondary radiation in the range of 200–315 nm (UVC and UVB) is ∼20% of the total intensity at high laser fluences (>2 J/cm²), and ∼50% at moderate laser fluences (<500 mJ/cm²); 10 μJ/cm² in the UVC and UVB were measured at the sample surface, at fluences (<1J/cm²) which are of relevance for clinical procedures on soft tissues. In dental tissue processing, very high fluences (>5 J/cm²) are required. As a consequence, laser–induced plasma formation can be observed. Secondary radiation can be used as a visible guide for selective removal of carious altered tissue. The data we have found might be of assistance in estimating potential hazards for future mutagenic studies in the field. © 1994 Wiley-Liss, Inc.     

The wound/burn guidelines – 6: Guidelines for the management of burns

Burns are a common type of skin injury encountered at all levels of medical facilities from private clinics to core hospitals. Minor burns heal by topical treatment alone, but moderate to severe burns require systemic management, and skin grafting is often necessary also for topical treatment. Inappropriate initial treatment or delay of initial treatment may exert adverse effects on the subsequent treatment and course. Therefore, accurate evaluation of the severity and initiation of appropriate treatment are necessary. The Guidelines for the Management of Burn Injuries were issued in March 2009 from the Japanese Society for Burn Injuries as guidelines concerning burns, but they were focused on the treatment for extensive and severe burns in the acute period. Therefore, we prepared guidelines intended to support the appropriate diagnosis and initial treatment for patients with burns that are commonly encountered including minor as well as moderate and severe cases. Because of this intention of the present guidelines, there is no recommendation of individual surgical procedures.     

Control of neonatal human dermal fibroblast migration on poly(lactic‐co‐glycolic acid)‐coated surfaces by electrotaxis

Many types of cells respond to applied direct current electric fields (dcEFs) by directional cell migration, a phenomenon called galvanotaxis or electrotaxis. In this study, electrotaxis was used to control cell migration. We designed a new electrotaxis incubator and chamber system to facilitate long‐term (> 12 h) observation and to allow for alterations to the direction of the current. Poly(lactic‐co‐glycolic acid) (PLGA) was coated onto surfaces to mimic a commonly used tissue‐engineering scaffolding environment. Neonatal human dermal fibroblasts (nHDFs) were grown on PLGA‐coated surfaces and exposed to EFs at increasing currents in the range 0–1 V/cm. These cells migrated toward the cathode during 3 h of dcEF stimulation; however, the migration speed decreased with increasing electric fields. Cells exposed to dcEFs in the range 1–2 V/cm showed no changes to migration speed or x forward migration indices (xFMIs) and the cells continued to move toward the cathode. nHDFs showed directional migration towards the cathode in direct current (dc) EFs (1 V/cm) and they moved in the opposite direction when the polarity of the dcEF was reversed. Reorganization of the actin cytoskeleton and polarization of the Golgi apparatus were evaluated by immunostaining, which showed that the actin cytoskeleton elongated towards the cathode and the Golgi apparatus polarized in the direction of the dcEF. This study revealed that cell migration could potentially be controlled on PLGA scaffolds through electrotaxis. Copyright © 2015 John Wiley & Sons, Ltd.