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991.
弓形虫复合粘膜疫苗滴鼻免疫小鼠诱导的Peyer’s patches持续性细胞免疫应答 总被引:1,自引:0,他引:1
目的以可溶性速殖子抗原(soluble tachyzoite antigen,STAg)和霍乱毒素(choleratoxin,CT)佐剂制备的弓形虫复合粘膜疫苗滴鼻免疫小鼠,观察肠粘膜诱导部位Peyer’s patches(PP)的细胞免疫应答及持续时间,探讨其免疫机制。方法BALB/c小鼠96只,随机分为实验组和对照组,实验组以STAg(20μg/只)为抗原,CT(1/μg/只)为佐剂滴鼻免疫,对照组PBS滴鼻。滴鼻2次(间隔2周)后,每组6只小鼠分别于第1、2、3、4、6、8、10、12周处死。计数PP个数,制备PP淋巴细胞悬液,计数并涂片;免疫细胞化学法检测CD4^+、CD8^+T细胞亚群。结果实验期间两组小鼠PP数目均无明显变化;实验组免疫后PP淋巴细胞数量明显增生,第2周达高峰,第1、2、3周显著高于对照组(P〈0.05),其中以CD4^+T细胞增生为主,第1周~第8周高于对照组(P〈0.01),CD8^+T细胞第1周~第4周显著增高(P〈0.01),CD4^+/CD8^+比值无显著变化(P〉0.05)。结论弓形虫复合粘膜疫苗滴鼻免疫BALB/c小鼠可有效诱导肠PP部位持续性的免疫应答,从而激活肠粘膜效应部位淋巴细胞的抗弓形虫感染作用。 相似文献
992.
《European journal of pharmaceutics and biopharmaceutics》2014,86(3):427-437
The objectives of this study were to characterise three prototype fenofibrate lipid-based formulations using a range of in vitro tests with differing levels of complexity and to assess the extent to which these methods provide additional insight into in vivo findings. Three self-emulsifying drug delivery systems (SEDDS) were prepared: a long chain (LC) Type IIIA SEDDS, a medium chain (MC) Type IIIA SEDDS, and a Type IIIB/IV SEDDS containing surfactants only (SO). Dilution, dispersion and digestion tests were performed to assess solubilisation and precipitation behaviour in vitro. Focussed beam reflectance measurements and solid state characterisation of the precipitate was conducted. Oral bioavailability was evaluated in landrace pigs. Dilution and dispersion testing revealed that all three formulations were similar in terms of maintaining fenofibrate in a solubilised state on dispersion in biorelevant media. During in vitro digestion, the Type IIIA formulations displayed limited drug precipitation (<5%), whereas the Type IIIB/IV formulation displayed extensive drug precipitation (∼70% dose). Solid state analysis confirmed that precipitated fenofibrate was crystalline. The oral bioavailability was similar for the three lipid formulations (65–72%). In summary, the use of LC versus MC triglycerides in Type IIIA SEDDS had no impact on the bioavailability of fenofibrate. The extensive precipitation observed with the Type IIIB/IV formulation during in vitro digestion did not adversely impact fenofibrate bioavailability in vivo, relative to the Type IIIA formulations. These results were predicted suitably using in vitro dilution and dispersion testing, whereas the in vitro digestion method failed to predict the outcome of the in vivo study. 相似文献
993.
Akram Moslehi Batool Hashemi-beni Azam Moslehi Maryam Ali Akbari Minoo Adib 《The Korean journal of physiology & pharmacology》2016,20(4):341-346
Membrane-bound HLA-G (mHLA-G) discovery on adipose derived stem cells (ADSCs) as a tolerogenic and immunosuppressive molecule was very important. Many documents have shown that HLA-G expression can be controlled via some hormones such as progesterone (P4) and estradiol (E2). Therefore, this study was designed to evaluate progesterone and estradiol effects on mHLA-G in ADSCs at restricted and combination concentrations. Three independent cell lines were cultured in complete free phenol red DMEM and subcultured to achieve suffi cient cells. These cells were treated with P4, E2 and P4 plus E2 at physiologic and pregnancy concentrations for 3 days in cell culture conditions. The HLA-G positive ADSCs was measured via monoclonal anti HLA-G-FITC/MEMG-09 by means of flow cytometry in nine groups. Data were analyzed by one way ANOVA and Tukey''s post hoc tests. There were no signifi cant values of the mean percentage of HLA-G positive cells in E2-treated and the combination of P4 plus E2-treated ADSCs compared to control cells (p value>0.05) but P4 had a signifi cant increase on mHLA-G in ADSCs (p value<0.05). High P4 concentration increased mHLA-G but E2 and the combination of P4 plus E2 could not change mHLA-G on ADSCs. 相似文献
994.
雄黄可溶性砷和价态砷与小鼠急性毒性关系的研究 总被引:1,自引:4,他引:1
目的:观察单次ig给药不同批号的雄黄混悬液后小鼠的中毒反应及死亡情况,用于初步评价受试物毒性,探讨不同批号的雄黄中可溶性砷和价态砷与小鼠急性毒性间的关系。方法:对3个不同批号的雄黄进行总砷含量、可溶性砷和价态砷的测定,根据预试验结果确定不同批号雄黄的最高剂量。将不同批号的雄黄混悬液分别按0.85依次递减的比例单次ig给药,观察给药后各组小鼠中毒反应及死亡情况,连续观察14 d,通过SPSS统计软件分析得半数致死量(LD50)及其95%的可信区间。结果:3个批号的雄黄总砷含量分别为95.5%,96.0%,94.8%,可溶性砷分别为3.32%,5.23%,6.73%,价态砷分别为1.39%,3.26%,4.36%,测得LD50分别为2.069 g·kg-1,1.319 g·kg-1,1.100 g·kg-1。用2倍LD50的雄黄上清液给药,结果小鼠全部死亡。结论:雄黄的毒性存在于可溶性部分,可溶性砷和价态砷含量与小鼠急性毒性间呈高度相关关系,LD50与可溶性砷和价态砷呈负相关关系,即可溶性砷和价态砷含量越高毒性越大,与总砷含量的相关性差。 相似文献
995.
PCOS is the most common cause of anovulation in reproductive-aged women with 70% experiencing ovulatory problems. Advanced glycation end products are highly reactive molecules that are formed by non-enzymatic reactions of sugars with proteins, nucleic acids and lipids. AGEs are also present in a variety of diet where substantial increase in AGEs can result due to thermal processing and modifications of food. Elevation in bodily AGEs, produced endogenously or absorbed exogenously from high-AGE diets, is further exaggerated in women with PCOS and is associated with ovulatory dysfunction. Additionally, increased expression of AGEs as pro-inflammatory receptors in the ovarian tissue has been observed in women with PCOS. In this review, we summarize the role of dietary AGEs as mediators of metabolic and reproductive alterations in PCOS. Once a mechanistic understanding of the relationship between AGEs and anovulation is established, there is a promise that such knowledge will contribute to the subsequent development of targeted pharmacological therapies that will treat anovulation and improve ovarian health in women with PCOS. 相似文献
996.
Increased regulatory T cells in patients with liver cirrhosis correlated with hyperbilirubinemia and predict bacterial complications 下载免费PDF全文
997.
998.
PurposeTo develop a high-throughput in vitro intestinal lipolysis (HTP) model, without any means of pH-stat-titration, to enable a fast evaluation of lipid-based drug delivery systems (LbDDS).Material and methodThe HTP model was compared to the traditionally used dynamic in vitro lipolysis (DIVL) model with regard to the extent of lipid digestion and drug distribution of two poorly soluble model drugs (cinnarizine and danazol), during digestion of three LbDDS (LbDDS I–III).ResultThe HTP model was able to maintain pH around 6.5 during digestion, without the addition of NaOH to neutralize the free fatty acids (FFAs), due to an increased buffer capacity. Cinnarizine was primarily located in the aqueous phase during digestion of all three LbDDS and did not differ significantly between the two models. The distribution of danazol varied from formulation to formulation, but no significant difference between the models was observed. The triacylglycerides (TAG) in LbDDS III were digested to the same extent in both models, whereas the TAG present in LbDDS II was digested slightly less in the HTP model. No TAG was present in LbDDS I and digestion was therefore not analyzed.ConclusionThe HTP model is able to predict drug distribution during digestion of LbDDS containing poorly water soluble drugs in the same manner as the DIVL model. Thus the HTP model might prove applicable for high-throughput evaluation of LbDDS in e.g. 96 well plates or small scale dissolution equipment. 相似文献
999.
Ionic liquids (ILs) are organic salts with a melting point below 100 °C. Active pharmaceutical ingredients (APIs) are transformed into ILs by combining them with typically large yet charged counterions. ILs hold promise to build a large design space for relevant pharmaceutical parameters, particularly for poorly water soluble drugs. It is for this wide design space that ILs may be the entry into the fascinating vision of modifying physico-chemical properties without the need to structurally modify the active pharmaceutical ingredient itself. This extremely intriguing pharmaceutical option is critically discussed including its potential and limitations. The review is starting off with an introduction to the metathesis and characterization of ILs, and leads over to examples for pharmaceutical application, including enhancement of dissolution rate and kinetic solubility and hygroscopicity adaptation, respectively. Tuning biopharmaceutics and toxicology by proper IL design is another focus. The review connects the interrelated chemical, physical, pharmaceutical, and toxicological outcome of API-ILs, serving as guidance for the formulation scientist who aims at expanding ones armamentarium for poorly water soluble APIs while avoiding structural modification, thereof. 相似文献
1000.
Novel formulations that overcome the solubility limitations of poorly water soluble drugs (PWSD) are becoming ever more critical to a drug development process inundated with these compounds. There is a clear need for developing bio-enabling formulation approaches to improve oral bioavailability for PWSD, but also to establish a range of predictive in vitro and in silico biopharmaceutics based tools for guiding formulation design and forecasting in vivo effects. The dual aim of this study was to examine the potential for a novel lipid based formulation, termed a lipidic dispersion, to enhance fasted state oral bioavailability of fenofibrate, while also assessing the predictive ability of biorelevant in vitro and in silico testing. Formulation as a lipidic dispersion improved both dissolution and solubilisation of fenofibrate through a combination of altered solid state characteristics and incorporation of solubilising lipidic excipients. These changes resulted in an increased rate of absorption and increased maximal plasma concentrations compared to a commercial, micronised product (Lipantil® Micro) in a pig model. Combination of biorelevant in vitro measurements with in silico physiologically based pharmacokinetic (PBPK) modelling resulted in an accurate prediction of formulation performance and forecasts a reduction in food effects on fenofibrate bioavailability through maximising its fasted state dissolution. 相似文献