Long-acting forms of Sonic hedgehog with improved pharmacokinetic and pharmacodynamic properties are efficacious in a nerve injury model

The therapeutic effects of the Sonic hedgehog (Shh) have been difficult to evaluate because of its relatively short serum half-life. To address this issue polyethylene glycol modification (PEGylation) was investigated as an approach to improve systemic exposure. Shh was PEGylated by a targeted approach using cysteines that were engineered into the protein by site-directed mutagenesis as the sites of attachment. Sixteen different versions of the protein containing one, two, three, or four sites of attachment were characterized. Two forms were selected for extensive testing in animals, Shh A192C, which provided a single site for PEGylation, and Shh A192C/N91C, which provided two sites. The PEGylated proteins were evaluated for reaction specificity by SDS-PAGE and peptide mapping, in vitro potency, pharmacokinetic and pharmacodynamic properties, and efficacy in a sciatic nerve injury model. Targeted PEGylation was highly selective for the engineered cysteines and had no deleterious effect on Shh function in vitro. Systemic clearance values in rats decreased from 117.4 mL/h/kg for unmodified Shh to 29.4 mL/h/kg for mono-PEGylated Shh A192C that was modified with 20 kDa PEG-maleimide and to 2.5 mL/h/kg for di-PEGylated Shh A192C/N91C modified with 2, 20 kDa PEG vinylsulfone adducts. Serum half-life increased from 1 h for unmodified Shh to 7.0 and 12.6 h for the mono- and di-PEGylated products. These changes in clearance and half-life resulted in higher serum levels of Shh in the PEG-Shh-treated animals. In Ptc-LacZ knock-in mice expressing lacZ under regulation of the Shh receptor Patched, about a 10-fold lower dose of PEG-Shh was needed to induce beta-galactosidase than for the unmodified protein. Therapeutic treatment of mice with PEG-Shh enhanced the regeneration of injured sciatic nerves. These studies demonstrate that targeted PEGylation greatly alters the pharmacokinetic and pharmacodynamic properties of Shh, resulting in a form with improved pharmaceutical properties.     

温经止痛凝胶膏剂的促渗剂优选

目的:优选温经止痛凝胶膏剂中促渗剂的种类及用量。方法:采用改良Franz扩散池,以离体小鼠腹部皮肤为屏障,采用HPLC检测不同促渗剂种类、比例及用量对温经止痛凝胶膏剂中藁本内酯累积透皮量、透皮吸收速率、增渗倍数等参数的影响,流动相甲醇-水(80∶20),检测波长328 nm。结果:氮酮和丙二醇联用的促渗效果明显优于其他几种促渗剂,确定氮酮与丙二醇的用量比(2∶1),总用量4%。藁本内酯24 h的累计透皮量84.16μg·cm-2,透皮速率常数3.28μg·cm-2·h-1,增渗倍数3.33。结论:氮酮和丙二醇组合的透皮促渗效果显著,可作为温经止痛凝胶膏剂的促渗剂。     

荜茇总生物碱对6-羟基多巴胺致帕金森病大鼠多巴胺能神经元损伤的保护作用研究

目的:探讨荜茇总生物碱(PLA)对6-羟基多巴胺(6-OHDA)致帕金森病(PD)大鼠多巴胺能神经元损伤的保护作用及其可能的机制。方法:采用脑立体定位单侧纹状体注射6-OHDA建立大鼠PD模型,将PD大鼠随机分为PLA组(PLA50 mg·kg-1·d-1),美多巴组(美多巴50 mg·kg-1·d-1)及模型组,每组15只,每日灌胃给药1次,连续6周。另随机选取15只大鼠在纹状体仅注射生理盐水作为假手术组。采用阿朴吗啡(APO)诱导的大鼠旋转及转棒实验进行行为学观察,酪氨酸羟化酶(TH)免疫组化检测大鼠黑质中TH阳性细胞数及纹状体中TH阳性纤维密度,用分光光度法检测大鼠黑质及纹状体内超氧化物歧化酶(SOD)、谷胱甘肽过氧化物酶(GSH-Px)、还原型谷胱甘肽(GSH)、过氧化氢酶(CAT)、丙二醛(MDA)、一氧化氮(NO)及一氧化氮合酶(NOS)的含量。结果:帕金森病大鼠在APO诱导后出现明显的旋转行为,且在转棒上的滞留时间缩短,黑质区TH阳性细胞数及纹状体TH阳性纤维密度明显减少,组织内SOD,GSH-Px,CAT的活力降低,NOS的活力升高,MDA,NO含量升高,GSH含量降低,总抗氧化能力明显降低。PLA能明显改善PD大鼠的行为学异常,增加黑质区TH阳性细胞数及纹状体TH阳性纤维密度,提高组织内SOD,GSH-Px,CAT的活力,降低NOS的活力,降低MDA和NO含量,提高GSH含量,总抗氧化能力明显提高。结论:荜茇总生物碱对6-OHDA致PD模型大鼠的黑质细胞具有保护作用,其机制可能与抗氧化活性有关。     

新疆芍药化学成分的研究

目的 :研究新疆芍药的化学成分。方法 :用柱色谱分离 ,利用化合物的理化性质及波谱方法鉴定。结果 :分离并鉴定了芍药苷 (paeoniflorinⅠ )、白芍苷 (albiflorinⅡ )、芍药新苷 (lactiflorinⅢ )、胡萝卜苷 (daucosterolⅣ )和蔗糖 (sucroseⅤ )等 5个成分。结论 :这些化合物均为首次从该植物中分离得到。另芍药新苷化学结构曾 2次被修正 ,本研究分析后确认了其中的 1个结论。     

HPLC测定蝉蜕止咳颗粒中黄芩苷和汉黄芩素含量

目的:建立高效液相色谱法测定蝉蜕止咳颗粒(蝉蜕、黄芩等)中黄芩苷和汉黄芩素含量的方法.方法:ODS(C18)色谱柱.乙腈-0.6%磷酸(45:55)为流动相;流速:1mL·min-1;柱温:40℃;检测波长275nm.结果:本法可测定蝉蜕止咳颗粒中黄芩苷和汉黄芩素含量.其分别在0.104μg～0.52μg和0.03μg～0.15μg范围内与峰面积成线性关系.平均回收率分别为100.69%和98.8%;RSD分别为1.75%和1.01%.结论:该方法简便、准确,可作为蝉蜕止咳颗粒的含量测定方法.     

Telling stories from everyday practice, an opportunity to see a bigger picture: a participatory action research project about developing discharge planning

In spite of laws, rules and routines, findings from Swedish as well as international research show that discharge planning is not a simple matter. There is considerable knowledge about discharge planning, but the quality of the actual process in practice remains poor. With this in mind, a research and developmental health and social care network decided to use participation action research to explore the discharge planning situation in order to generate new ideas for development. This paper reports on the research process and the findings about our enhanced understanding about the discharge planning situation. Story dialogue method was used. The method is based on stories from everyday practice. The stories are used as 'triggers' to ask probing questions in a dialogical and structured form. Local theory is developed to help the participants to find solutions for action in the practice. Our findings were that the discharge planning situation could be seen as a system including three interconnected areas: patient participation, practitioners' competence and organizational support. To reach good quality in discharge planning, all these three issues need to be developed, but not only as routines and forms. Rather, when developing a discharge planning situation, a system where relational aspects such as confidence and continuity are essential and thus needs to be considered. To achieve a change, the core problem needs to be clarified. When the issue is complex, the solution needs to consider the bigger picture and not just the parts. Telling stories from everyday practice, and to systematically reflect and analyse those in interprofessional groups can create opportunities for enhanced understanding, as well as be a vehicle for future change of practice.     

Community‐Based Practice Experience of Unsuspected Breast Magnetic Resonance Imaging Abnormalities Evaluated With Second‐Look Sonography

Objective. The purpose of this study was to assess the utility and efficacy of second‐look breast sonography in the evaluation of abnormalities identified on presurgical breast magnetic resonance imaging (MRI) examinations. Methods. A retrospective review was performed of 152 presurgical breast MRI examinations having 196 unsuspected abnormalities to identify findings that underwent subsequent breast sonography. Eligible examinations had a suspicious abnormality identified on presurgical MRI and documentation of the location and size of the finding on MRI and subsequent second‐look sonography. Fourteen examinations not meeting the criteria were excluded, with 182 abnormalities remaining. Patient medical records were reviewed. Results. Seventy percent (128 of 182) of breast MRI lesions were visible at second‐look sonography; 30% (54 of 182) were sonographically occult. Ninety‐five percent (121 of 128) of sonographically visible abnormalities underwent breast biopsy. Pathologic examinations of sampled sonographically visible lesions revealed 39 cancers, 9 high‐risk lesions, 72 benign lesions, and 1 lesion not specified at surgery; 23% (9 of 128) of cancers were in the contralateral breast. Fifty‐four lesions were sonographically occult. Needle biopsy was performed for 93% (50 of 54) of occult lesions, revealing 8 cancers, 1 high‐risk lesion, and 41 benign lesions; 3 of the benign lesions did not have sufficient pathologic specimens but were benign at follow‐up. Magnetic resonance imaging guidance was used in 86% (43 of 50) of these biopsies. One contralateral cancer was identified in the sonographically occult subset. Of the 182 lesions that underwent second‐look sonography, 20% (36 of 182) had a change in management. Conclusions. Second‐look sonography has value in the evaluation of abnormalities found on breast MRI. We found enhancements in 70% (128 of 182), yielding 39 cancers.