Benzoyl Peroxide Solubility and Stability in Hydric Solvents

Saturated solubility and reaction rate constants for the decomposition of benzoyl peroxide in solution and suspension were determined for use in formulation development. The solvents studied included ethanol, propylene glycol, and cosolvent mixtures of PEG 400 and water. The solubility of benzoyl peroxide was inversely related to the solvent polarity, with greater solubility occurring with semipolar solvents. The stability of benzoyl peroxide in solution was dependent on the solvent, concentration of benzoyl peroxide, and temperature. The compound was least stable in PEG 400. Stability was improved when water was added to PEG 400. Similar solvent effects were observed in suspension. In benzoyl peroxide suspensions of PEG 400 and PEG 400/water blends, benzoyl peroxide stability was dependent on solubility, with improved stability occurring in blends where the benzoyl peroxide was least soluble. Thus, solution formulations of benzoyl peroxide in pharmaceutically acceptable solvents are unlikely to show good stability; however, suspension formulations should be reasonably stable if the vehicle is selected to provide low benzoyl peroxide solubility.     

A comparative study of the proteolytic enzymes of Trypanosoma brucei, T. equiperdum, T. evansi, T. vivax, Leishmania tarentolae and Crithidia fasciculata

Four types of proteolytic activity were detected in the bloodstream form of each of the four Trypanosoma species: (i) HPAase, active on hide powder azure and detected on polyacrylamide gels containing denatured haemoglobin; (ii) AZCase, active on azocasein; (iii) type 1, active on the chromogenic peptide N-benzoyl-L-prolyl-L-phenylalanyl-L-arginine p-nitroanilide in the presence of dithiothreitol, and (iv) type 2, active against several nitroanilide derivatives in the absence of dithiothreitol. Studies of the pH optimum, dithiothreitol requirement and inhibitor sensitivities of the proteolytic activities suggested that: (a) HPAase and type 1 activities could be due to the same enzymes, probably a family of cysteine proteinases; (b) AZCase had some characteristics of a cysteine proteinase, but was not identical to HPAase, and (c) type 2 activity could be due to a serine proteinase. Procyclic T. brucei contained relatively low cysteine proteinase activities (HPAase, AZCase and type 1) but high type 2 activity. Their proteolytic enzymes thus were apparently more similar to those in Crithidia fasciculata and Leishmania tarentolae promastigotes than those in T. brucei bloodstream forms.     

苦参总碱抗实验性心律失常的作用

目的：研究苦参总碱抗实验性心律失常的作用。方法：本研究采用冠脉结扎，BaCl2肾上腺素，乌头碱，哇巴因诱发的心律失常模型。结果：苦参总碱能明显对抗大鼠冠脉结扎后诱发的早期缺血性心律失常；对BaCl2诱发的大鼠心律失常有预防和治疗作用；缩短静注肾上腺素诱发的家兔心律失常持续时间；增加乌头碱诱发大鼠心律失常的剂量；增加哇巴因诱发豚鼠心律失常的剂量。结论：苦参总碱对多种心律失常模型有预防或治疗作用，其抗心律失常机制是多方面的。     

Study on Metabolites of Aconitum Alkaloids in Human Urine

TheaconitebelongstoplantsofgenusAconituminfamilyofRanunculaceaandhavenotableclinicalfunctionsintreatingrheumaticarthritis ,heartfailure ,etc .However,accidentsofaconitine(fromaconite)poisoningfrequentlyoccurtomanypeopletakingtheseherbs .Theplantsofthisfamilycontainaconitine ,mesaconitine ,hypaconitineandotheraco nitumalkaloids .Theyarehighlytoxic ,andtheirtreatmentdoseapproachestothetoxicdoseorlethaldose .Duringtheperiodfrom 1989- 1995 ,morethan 30casesofpoisoningcausedbyaconitineinsometradit…     

复方雪莲胶囊的质量标准研究

目的:建立复方雪莲胶囊(雪莲,延胡索,制川乌等)的质量标准,以便更有效地控制产品质量.方法:鉴别项、检查项采用薄层色谱法(TLC).含量项采用高效液相色谱法(HPLC)测定制剂中的延胡索乙素.高效液相色谱条件:Kroma-sil ODS-1 C18柱,流动相:甲醇-磷酸盐缓冲液(65:35).结果:TLC具有专属性.HPLC准确可靠,回收率为100.7%,RSD为1.6%.结论:该标准可用于复方雪莲胶囊的质量控制.     

草乌提取物乌头碱和新乌头碱的透皮速率测定

目的:测定草乌提取物中乌头碱、新乌头碱的透皮速率。方法:用改良Franz扩散池法收集草乌提取物的透皮接受液,用高效液相色谱法测定其中乌头碱、新乌头碱的透皮速率。结果:在促透剂氮酮和丙二醇各为4%的条件下,浓度为600mg/ml的草乌提取物中乌头碱、新乌头碱24h的累积渗透量分别为165.819和487.747μg/cm2;透皮速率常数分别为18.391和78.805μg·cm-2·h-1。结论:草乌提取物中乌头碱、新乌头碱在氮酮和丙二醇的促透作用下能较好地透过大鼠皮肤,透皮吸收过程符合Higuchi方程。     

基于AHP-熵权法优选黑顺片炮制工艺及生物碱类成分动态变化研究

目的 采用主观评价层次分析法（analytic hierarchy process，AHP）-熵权法优选黑顺片炮制工艺，探究炮制过程中生物碱类成分动态变化规律。方法 采用外观性状、水溶性浸出物、苯甲酰新乌头原碱含量、苯甲酰乌头原碱含量、苯甲酰次乌头原碱含量、双酯型生物碱总量作为评价指标，基于单因素考察结果，以煮制时间、水漂次数、蒸制时间、干燥温度为主要因素建立正交实验，通过AHP-熵权法优选黑顺片最佳炮制工艺参数。采用HPLC法对各炮制环节的附子进行含量测定，分析比较6种酯型生物碱的含量变化。结果 在质量分数20%以上的胆巴溶液中浸泡能达到防腐的目的，且浸泡20d以上附子的质量相对稳定。黑顺片炮制的最佳工艺条件为煮制时间8min，水漂次数4次，蒸制时间3h，干燥温度60℃；炮制过程中双酯型生物碱总量逐渐降低，泡胆和漂洗过程单酯型生物碱含量降低，煮制和蒸制过程单酯型生物碱含量升高。结论 实验优化所得的黑顺片炮制工艺合理、稳定、可行，炮制过程中各环节对酯型生物碱类成分均有不同程度的影响，可为进一步探讨黑顺片的现代炮制方法提供参考。     

415 nm蓝光联合5%过氧苯甲酰凝胶治疗轻中度寻常性痤疮的疗效

 目的 观察415 nm蓝光联合5%过氧苯甲酰凝胶治疗轻中度寻常性痤疮的临床疗效与安全性。方法 选取武警湖北总队医院2019-03至2020-09轻中度寻常性痤疮90例,随机分为3组,每组30例。联合组同时予415 nm蓝光照射联合5%过氧苯甲酰凝胶外用;蓝光组和药物组分别予415 nm蓝光照射和5%过氧苯甲酰凝胶外用。3组均在治疗8周后判定疗效。结果 治疗8周后联合组有效率为83.3％。蓝光组和药物组有效率分别为30％和56.7％,与联合组有效率比较,差异均有统计学意义。治疗过程中不良反应少见且患者均可耐受。结论 415 nm蓝光联合5%过氧苯甲酰凝胶治疗轻中度寻常性痤疮疗效显著,不良反应少。     

The pulsed‐dye laser as an adjuvant treatment modality in acne vulgaris: a randomized controlled single‐blinded trial

Background Acne vulgaris is the most common skin disease and can pose a substantial therapeutic challenge. Recently, several phototherapeutic modalities, most notably pulsed‐dye laser (PDL) treatment, have been introduced, but the published results – albeit promising – are controversial. Objectives To assess the efficacy of an adjuvant PDL treatment when combined with a proven topical treatment [fixed‐combination clindamycin 1%–benzoyl peroxide 5% hydrating gel (C/BPO)]. Methods Eighty patients (38 males and 42 females, mean ± SD age 19·7 ± 5·9 years) were randomized in a 1 : 2 ratio to receive C/BPO alone or in combination with PDL treatment (wavelength 585 nm, energy fluence 3 J cm⁻², pulse duration 0·35 ms, spot size 7 mm). Patients were evaluated at baseline and at 2 and 4 weeks after initial treatment. The primary end points were the Investigator’s Static Global Assessment (ISGA) score and lesion count; the secondary end point was the Dermatology Life Quality Index (DLQI). Results Both groups showed a significant improvement during observation [ISGA 27·1% (C/BPO) and 24·6% (C/BPO + laser), total lesion count 9·2% and 9·0%, inflammatory lesion count 36·3% and 36·9%, DLQI 54·5% and 42·5%], but there was no significant or otherwise appreciable difference between treatment modalities as far as the extent of improvement was concerned. Patients with more severe findings at baseline had a greater benefit from either therapy regimen. Conclusions Our findings do not support the concept of a substantial benefit of PDL treatment in acne vulgaris.