冰片作为涂膜剂促透剂对小鼠经皮给药后皮肤上皮细胞超微结构观察

用复方蛇床子涂膜剂对小鼠皮肤进行了透皮形态结构观察,小鼠皮肤角质层经涂膜剂透皮1 h即可见角质层翘起,形成空泡,可见基底颗粒层细胞水肿,透皮3 h角质层细胞开始脱落;至6 h基底颗粒层细胞翘起,基底颗粒层以外的细胞全部脱落。结果表明该透皮制剂可通过破坏皮肤角质层来促进中药成分的透皮吸收,对真皮层未见明显变化。     

洛美沙星（Lomefloxacin）透皮吸收搽剂中氮酮的最佳浓度

应用洛美沙星搽剂作为模型药物，采用离体鼠皮，研究了氮酮（Azone)在0%，1%，3%，5%，7%浓度时对洛美沙星透皮吸收的影响。试验结果表明，氮酮在洛美沙星透皮吸收搽剂中最佳浓度为4.01%。     

低频超声透皮给药的作用机制和影响因素

低频率超声可以提高药许多药物的透皮传输,其机制有多种解释,但最被普遍认可的是超声的空化作用,多数研究人员认为超声是通过改变皮肤角质层角化细胞的排列结构来促进药物的透皮吸收。低频超声透皮给药在离体和动物活体实验研究上得到广泛的应用,不论是小分子药物的透皮吸收还是大分子药物的透皮吸收都取得了不错的成果。然而临床上应用低频超声介导药物进行治疗的相关报道不多。若低频超声给药的安全性得到证实,低频超声透皮给药必将成为一种安全、快速、可控、有效、经济的新型给药方式。     

抗动物寄生虫药的几种特殊剂型

1透皮吸收剂透皮吸收是使抗寄生虫药物通过皮肤或黏膜吸收，进人血液循环，再分布到宿主全身与寄生虫接触。皮肤本身能吸收少量药物，但一般达不到驱杀体内和体外其他部位寄生虫的作用。透皮吸收剂系加入促进药物渗透吸收的促进剂而使药物能够较多被皮肤吸收而转入血液中。渗透促进剂有氮酮、二甲亚     

洛美沙星搽剂防治仔猪黄、白痢试验报告

大肠杆菌是一种条件性致病菌。应用抗生素治疗大肠杆菌病的用药途径一向是打针、灌药,但旧方法既低效又费力。本文研究透皮吸收制剂———洛美沙星搽剂对仔猪黄白痢的临床防治效果,现报告如下:1材料与方法1.1试验用药物洛美沙星透皮吸收搽剂(以下简称洛美沙星搽剂)以洛美沙星原料药(江苏常州第二制药厂生产)与氮酮(广东省助剂化工厂生产)按药剂学方法由福建农林大学研制。该搽剂每毫升含洛美沙星4毫克。本文所用的盐酸洛美沙星注射液(洛奇),为常州第二制药厂兽药分厂生产,批号:9904291。1.2参试仔猪及分组设计试验分洛美沙星搽剂预防和治疗…     

溶液载体和用药部位对甲硝唑在犬中透皮吸引的影响

研究不同的溶液载体(PBS,5%薄荷醇和5%氮酮)和不同部位的皮肤对甲硝唑在犬中体外透皮吸收和皮内摄取的影响.取下北京犬颈部、胸部以及腹部皮肤,-20℃保存.使用时,皮肤解冻固定在改良Franz透皮扩散仪上,保持恒速(200±1)r/min,恒温(35±0.5)℃.在扩散池中的皮肤角质层上加入2 mL溶液载体(含甲硝唑58.4 μmol),以20%乙醇为溶剂溶解薄荷醇和氮酮,在预定时间点取样1 mL,采用HPLC方法测定各接受液中的药物量和皮肤中摄取的药物量.结果显示,与PBS相比,薄荷醇和氮酮能增加所有部位甲硝唑的透皮吸收量和皮内摄取量(P<0.05).同一溶液载体在不同部位的渗透性存在差异,腹部>颈部>胸部,不同部位的皮内摄取量也存在差异,颈部>胸部>腹部.说明甲硝唑在不同溶液载体和不同部位皮肤的渗透性存在差异.     

抛物线拟合法研究氮酮(Azone)促进左旋咪唑透皮吸收的最佳浓度

采用静态小室装置,以左旋咪唑(LMS)为模型药物,用离子对HPLC法测定LMS浓度.采用抛物线拟合法建立不同时间下氮酮(Azone)浓度对LMS透皮吸收率的数学模型.用此模型准确求得氮酮对LMS透皮吸收的最佳浓度是3.05±0.57%,同时证明氮酮对LMS有显著的透皮吸收作用.     

不同浓度促透剂对绿原酸体外透皮吸收的影响

目的:通过小鼠体外透皮实验,探讨不同促透剂对绿原酸巴布剂药贴体外透皮吸收的影响,确定最佳促透剂及其浓度,为研制绿原酸透皮吸收制剂奠定良好的基础。方法:采用改良Franz扩散池法,以离体小鼠皮肤为透皮屏障,加入不同浓度促透剂制备绿原酸巴布剂药贴,以HPLC法考察绿原酸不同时间透过量,以绿原酸为定量指标进行体外透皮吸收检测。结果:单一促透剂中以1%氮酮效果最佳,5%油酸效果次之。结论:常用促透剂氮酮、油酸均可以使巴布剂中的绿原酸透过皮肤,且以1%氮酮促透效果最佳。     

三组药物对离体猪皮不同部位透皮效果的研究

采用ZRS－4型智能溶出仪为体外透皮装置，用紫外分光光度计检测3组药物（黄连＋冰片、黄连＋冰片＋氮酮、黄连＋蒽诺沙星＋氮酮）对仔猪不同部位（腰背部、腹侧部、腹底部）离体皮肤的透过率。结果，相同药物在不同部位的透皮率差异显著（P＜0．05）；3组药物在相同部位的透皮率无显著差异（P＞0．05）。表明，机体用药部位的选择对皮治疗的效果具有重要意义。     

兽用透皮贴剂研究概况

透皮给药系统操作简便、不良反应少,药物吸收不受消化道复杂环境的影响。透皮贴剂作为透皮给药的主要剂型,它还具有药物释放持久、可随时终止给药,有效减少过量给药和过敏反应的发生。尤其随着伴侣动物和马产业的发展,兽药透皮贴剂逐渐成为现代兽药制剂的研究热点之一。论文阐述国内外兽用贴剂的发展现状以及透皮贴剂的给药优势,从透皮贴剂中药物分子穿过皮肤角质层进入血液循环的过程、影响药物分子透过皮肤进入机体的因素以及相对应的促进吸收方法等方面对透皮贴剂进行了综述。     

促渗剂促进药物透皮吸收机理的研究进展

综述了促渗剂促进药物透皮吸收机理的研究概况,着重介绍了氮酮、油酸和萜烯等常用促渗剂的促渗机理研究进展,并提出透皮吸收机理研究发展趋势,为该领域进一步深入研究提供参考.     

The stratum corneum: the rampart of the mammalian body

Background –  The stratum corneum (SC) is the outermost region of the epidermis and plays key roles in cutaneous barrier function in mammals. The SC is composed of ‘bricks’, represented by flattened, protein‐enriched corneocytes, and ‘mortar’, represented by intercellular lipid‐enriched layers. As a result of this ‘bricks and mortar’ structure, the SC can be considered as a ‘rampart’ that encloses water and solutes essential for physiological homeostasis and that protects mammals from physical, chemical and biological assaults. Structures and functions –  The corneocyte cytoskeleton contains tight bundles of keratin intermediate filaments aggregated with filaggrin monomers, which are subsequently degraded into natural moisturizing compounds by various proteases, including caspase 14. A cornified cell envelope is formed on the inner surface of the corneocyte plasma membrane by transglutaminase‐catalysed cross‐linking of involucrin and loricrin. Ceramides form a lipid envelope by covalently binding to the cornified cell envelope, and extracellular lamellar lipids play an important role in permeability barrier function. Corneodesmosomes are the main adhesive structures in the SC and are degraded by certain serine proteases, such as kallikreins, during desquamation. Clinical relevance –  The roles of the different SC components, including the structural proteins in corneocytes, extracellular lipids and some proteins associated with lipid metabolism, have been investigated in genetically engineered mice and in naturally occurring hereditary skin diseases, such as ichthyosis, ichthyosis syndrome and atopic dermatitis in humans, cattle and dogs.     

Characterization of the canine skin barrier restoration following acute disruption by tape stripping

The stratum corneum (SC) forms the main part of the permeability barrier of the skin. In mice and in humans, cutaneous barrier disruption can be generated by removing the SC with tape stripping (TS) and the skin barrier function can be assessed by measurement of transepidermal water loss (TEWL). The aim of the present study was to characterize the skin barrier restoration in the dog following mechanical disruption and to analyse the correlation between the skin barrier recovery and TEWL measurement. Thirty sequential TS were performed on 12 sites on four healthy beagle dogs. The number of TS was chosen to ensure a sufficient barrier disruption with a slow recovery. Skin repair was assessed for 72 h by clinical and histological examinations, and TEWL measurements. The results showed that performing 30 TS was adequate to disrupt the skin barrier in the dog. The homeostatic repair response, initiated in the skin, was rapid and characterized by complete restoration of the SC within 72 h, accompanied by greater basal cell proliferation, and dermal eosinophilic inflammation. TEWL was significantly increased by complete removal of the SC but recovered along with restoration of the SC (Scheffe test, P ≤ 0.05). Characterization of a canine model of barrier disruption and restoration and assessment of the skin barrier function by TEWL measurements could help better understand the events implied in skin barrier function. Development of this canine model is also necessary for future studies on the effects of treatments aimed at restoring the skin barrier.     

In vitro development and characterization of canine epidermis on a porcine acellular dermal matrix

The aim of this study was to develop and to characterize a canine skin epidermal model able to form a proper epidermis on a porcine acellular dermal matrix (PADM). In addition, the role of fibroblasts in skin barrier formation was studied by incorporating or omitting canine dermal fibroblasts in the PADM. Canine epidermal composites were developed by seeding keratinocytes onto the surface of PADM that were previously seeded or non-seeded with dermal fibroblasts. After 14days of culture under air-exposed conditions and in a special growth medium, skin composites were histologically processed and immunohistochemically characterized to determine the expression of cytokeratins and of vimentin and the presence of basement membrane. In all composites, keratinocytes underwent differentiation to a multilayer epidermis with 5-7 viable cell layers. The stratum basalis, stratum spinosum, stratum granulosum and stratum corneum were identified. The expression of cytokeratins was similar to that described in healthy canine epidermis. Laminin and collagen IV immunostaining revealed a homogeneous layer in the epidermal-dermal junction only when the matrix had been seeded by canine dermal fibroblasts. The model may become a simple, useful and cost-effective tool to investigate the biology and pathology of canine epidermis and could partially replace animal testing in several areas of dermatological research.     

Effect of protein malnutrition on the skin epidermis of hairless mice

The purpose of this study was to evaluate the effect of protein malnutrition on the skin epidermis of mice. A low protein diet induced thinning of the skin epidermis, a decrease of cell proliferative activity in epidermal cells and a decrease of stratum corneum hydration. Dityrosine was immunostained in the cytoplasm of epidermal cells in the low protein diet group. Plasma advanced oxidation protein product (AOPP) levels were significantly more increased in the low protein diet group than in the control diet group. These results suggest that protein malnutrition adversely affects the structure and water barrier and reservoir functions of the skin epidermis, and these pathological changes are associated with the expressions of protein oxidation markers, dityrosine and AOPP.     

固体脂质纳米粒内服吸收机制及影响因素研究进展

大多数兽药由于渗透性、稳定性和溶解性差以至于无法抵御胃肠道化学和酶等不利环境的降解,不能有效突破胃肠道黏膜屏障,导致生物利用度并不理想.如何保护药物的稳定性并突破消化道黏膜屏障从而提高药物的内服吸收是药物研究者急需寻找解决方案的科学难题.固体脂质纳米粒能提高药物的稳定性并通过不同的转运方式突破胃肠道生理学屏障,从而有效...     

Characterization and quantification of ceramides in the nonlesional skin of canine patients with atopic dermatitis compared with controls

As in humans, there is mounting evidence in support of an abnormal skin barrier contributing to the pathogenesis of canine atopic dermatitis (AD). Studies in people with AD have associated an abnormal skin barrier with deficiencies in ceramides, which represent important components of the stratum corneum (SC) intercellular lipid lamellae. Therefore, the goal of this study was to determine if the SC of dogs with AD is deficient in ceramides compared to normal dogs. Samples of SC were obtained from nonlesional skin of the caudal abdomen of 14 patients with AD and 14 age-, breed- and sex-matched healthy controls using a cyanoacrylate stripping procedure, and the subclass and relative amount of ceramides were assessed blindly by thin layer chromatography. Paired t -tests using R statistical computer software revealed the percentage amounts of ceramides 1 and 9 were significantly lower in nonlesional skin of AD dogs compared to controls ( P = 0.034 and P = 0.047, respectively), and the cholesterol percentage amount was significantly higher in AD dogs than in controls ( P = 0.016). Furthermore, the cholesterol/ceramide ratio was significantly higher in the AD group with respect to controls ( P = 0.014). These findings suggest that decreased amounts of ceramides in the skin of dogs with AD may be involved in the impaired barrier function of their skin.     

Transepidermal water loss (TEWL) reflects skin barrier function of dog

The correlation between skin barrier function and transepidermal water loss (TEWL) was evaluated in dogs. Stratum corneum (SC) of 10 healthy dogs was removed by tape stripping (TS), which decreased the corneal layer to allow for permeation of fluorescent dye into skin. TEWL of damaged skin was measured with the closed-chamber-type TEWL analyzer, CC-01. The frequency of TS was directly related to the decrease of SC and the increased permeation of fluorescent dye, and TEWL increased with increasing impairment of skin barrier function. The results suggest that increased TEWL reflects impaired canine skin barrier function.     

日粮碳水化合物结构对瘤胃发酵及消化代谢影响的研究进展

碳水化合物是反刍动物营养的一个重要组成部分,不同结构的碳水化合物在瘤胃内发酵的速度和程度并不一致,从而影响日粮中营养物质的消化吸收。作者综述了不同比例的结构性碳水化合物(structural carbohydrates,SC)和非结构性碳水化合物(non-structural carbohydrate,NSC)对动物采食量、消化率和瘤胃发酵的影响。