8-甲氧补骨脂素凝胶的制备与质量控制

目的研制8-甲氧补骨脂素凝胶,确定该药的质量控制方法.方法以卡波姆-940作为凝胶基质,以8-甲氧补骨脂素为主药制备凝胶.采用高效液相色谱法测定主药的含量,并对制剂的稳定性进行考察.结果制备的凝胶均匀、细腻、分散性好,建立的分析方法不受辅料的干扰,相对回收率平均为99.18%,RSD为0.87%(n＝5).结论该制剂制备工艺简单,所得凝胶稳定性好.     

甲氧补骨脂素凝胶的制备与质量控制

目的研制8-甲氧补骨脂素凝胶，确定该药的质量控制方法。方法以卡波姆-940作为凝胶基质，以8-甲氧补骨脂素为主药制备凝胶。采用高效液相色谱法测定主药的含量，并对制剂的稳定性进行考察。结果制备的凝胶均匀、细腻、分散性好，建立的分析方法不受辅料的干扰，相对回收率平均为99.18%，RSD为0.87%(n＝5)。结论该制剂制备工艺简单，所得凝胶稳定性好。     

高效液相色谱法同时测定复方8-甲氧补骨脂素洗剂中主药含量

目的:建立复方8-甲氧补骨脂素洗剂中复方8-甲氧补骨脂素和醋酸肤轻松含量测定的高效液相色谱法.方法:采用Waters Symmetry C18色谱柱(250mm×4.6mm,5μm),流动相为甲醇-水(70:30),检测波长为240nm,流速为1.0ml·min-1.结果:8-甲氧补骨脂素浓度在20.232～101.16mg·L-1范围内与峰面积呈良好的线性关系(r=0.9999),平均回收率为100.70%(RSD为0.82%).醋酸肤轻松浓度在5.232～26.16 mg·L-1范围内与峰面积呈良好的线性关系(r=0.9998),平均回收率为100.8%(RSD为1.11%).结论:本法简便、快捷,结果准确,适用于该制剂的质量分析检验.     

反相高效液相色谱法测定8-甲氧补骨脂素乳膏的含量

目的:建立一种反相高效液相色谱法测定8-甲氧补骨脂素乳膏中主药的含量。方法:采用以碳十八烷基键合硅胶柱为色谱柱,甲醇-水(70∶30)为流动相,检测波长为249nm的外标法测定含量。结果:8-甲氧补骨脂素在8～80μg·mL~(-1)(r=0.9999,n=5)浓度范围内呈良好线性关系,其平均回收率为98.26%～99.46%;RSD为0.50%～1.58%。结论:该方法简便、灵敏、快速、准确。     

8-甲氧补骨脂素脂质体凝胶的皮肤渗透性研究

目的 :研究8 -甲氧补骨脂素脂质体凝胶的皮肤渗透性。方法 :以凝胶与敏白灵酊为对照 ,将8 -甲氧补骨脂素脂质体凝胶应用于离体及在体大鼠皮肤 ,用反相高效液相色谱法测定接收介质、皮肤、血液及其它组织中8 -甲氧补骨脂素的含量。结果 :离体条件下 ,脂质体凝胶具有最小的透皮速率和最大的皮内滞留量 ;在体条件下 ,包封于脂质体中的药物在皮肤中滞留量分别是凝胶和酊剂的 (4 37±0 91)倍和 (3 36±0 58)倍。结论 :8 -甲氧补骨脂素脂质体凝胶具有显著的局部皮肤靶向性。     

复方8-甲氧补骨脂素凝胶的研制及临床疗效

目的 对8-甲氧补骨脂素／醋酸地塞米松凝胶的制备和质量控制进行研究，并观察其临床疗效。方法 采用新型辅料卡波姆-980等为基质制成凝胶剂，用HPLC测定两主药含量，并对其外观、稳定性、临床疗效等进行考察。结果 复方8-甲氧补骨脂素凝胶外观均匀细腻，两主药平均回收率分别为100．1％和99．9％，RSD分别为0．33％和0．42％。治疗组临床疗效优于对照组。结论 该制剂处方合理，制备工艺简便，稳定性好，质量易于控制，且临床疗效较好。     

反相高效液相色谱法测定白癜风治疗药脂质体凝胶中8-甲氧补骨脂素的含量

目的：建立一种反相高效液相色谱法测定8－甲氧补骨脂素脂质体凝胶中主药含量的方法。方法：采用C18柱，甲醇－水（70：30）为流动相，检测波长为249nm，氢化可的松为内标。结果：8－甲氧补骨脂素在0.8-8mg.L^-1（r=0.9999,n=6)浓度范围内呈线性关系，其平均回收率为98．26％－99．46％；RSD为0．50％－1．58％，结论：该方法简便，灵敏，快速，准确。     

8-甲氧补骨脂素治疗寻常性斑块型银屑病随机双盲平行对照临床研究

目的评价比较进口与国产的8-甲氧补骨脂素片口服结合UVA UVB照射治疗寻常性斑块型银屑病的临床疗效及安全性。方法用随机双盲、平行对照试验方法,60例患者随机口服进口或国产8-甲氧补骨脂素片,剂量为0.6 mg·kg-1,2h后照射UVA和UVB,每周3次,疗程8周,观察疗效与安全性。结果通过8周的治疗,进口8-氧补骨脂素组PASI总分下降了96.3％,基愈率为92.9％,有效率为100％;国产8-甲氧补骨素组PASI总分下降98.5％,基愈率和有效率均为100％,两组间基愈率和有效率比较无显著性差异(P>0.05)。进口8-甲氧补骨脂素片药物不良反应发生率为46.4％,国产8-甲氧补骨脂素组为40％。药物不良反应多为轻中度消化道及皮肤瘙痒、色素沉着等。结论进口与国产8-甲氧补骨脂素片在进行银屑病PUVA疗法中都具有良好疗效及安全性。     

反相高效液相色谱法测定补骨脂素和异补骨脂素的含量

目的:测定制斑素注射液中补骨脂素和异补骨脂素的含量.方法:采用反相高效液相色谱法,色谱柱为Spherisorb C18分析柱(150 mm×4.0 mm,5μm),流动相为甲醇-水(50∶60),紫外检测波长为295 nm,柱温为35℃,流速为1.1 mL/min.结果:补骨脂素浓度在10～90μg/mL(r=0.9999)范围内,异补骨脂素浓度在10～90μg/mL(r=0.999 8)范围内与峰面积呈线性关系;补骨脂素和异补骨脂素平均回收率(n=5)分别为98.52%(RSD=1.6%)和99.30%(RSD=1.6%).结论:反相高效液相色谱法操作简便、快速、准确、可行,可用于测定制斑素注射剂中补骨脂素和异补骨脂素的含量和该制剂的质量控制.     

8-甲氧补骨脂素脂质体凝胶对实验性白癜风的药效学

目的:以8-甲氧补骨脂素(MOP)酊剂和凝胶剂为对照,考察8-甲氧补骨脂素脂质体(LMOP)凝胶对实验性白癜风的作用.方法:用化学脱色法制备白癜风动物模型,分别用等浓度(0.15%)MOP酊剂、凝胶剂、脂质体凝胶进行治疗,并给予日光照射15 min,考察其对皮肤黑素形成和胆碱酯酶的影响.结果:LMOP凝胶相对其他剂型对实验性白癜风有良好的治疗作用,对皮肤黑色素的影响和对胆碱酯酶的影响与模型组比较, 差异有极显著性(P<0.01), 与MOP凝胶组和酊剂组比较,差异有显著性(P<0.05).结论:LMOP凝胶较其他MOP制剂对白癜风有更好的治疗作用,为临床应用提供了理论依据.     

甲氧沙林联合窄谱中波紫外线治疗白癜风的临床效果研究

目的探讨甲氧沙林联合窄谱中波紫外线治疗白癜风的临床效果。方法 77例白癜风患者被随机分为实验组(n=39)和对照组(n=38),对照组单纯给予甲氧沙林治疗,实验组给予甲氧沙林溶液联合窄谱中波紫外线治疗。结果实验组总有效率为94.9%,显效率为79.5%,临床效果显著优于对照组(P<0.05)。结论甲氧沙林溶液联合窄谱中波紫外线应用于白癜风患者的治疗,能显著提高临床效果,改善患者生活质量,值得在临床上应用和推广。     

桃红清血丸治疗气滞血瘀型白癜风的临床疗效观察

目的:观察用桃红清血丸治疗气滞血瘀型白癜风的临床疗效。方法:将入选的100例白癜风患者随机均分为试验组(服用桃红清血丸并外搽甲氧沙林溶液)和对照组(服用胱氨酸和维生素B6并外搽甲氧沙林溶液),疗程为3个月。治疗前、后检测肝肾功能和外周血T淋巴细胞亚群CD+4、CD+8。结果:试验组有效率、CD+4/CD+8差值与对照组比较有显著性差异(P<0.05);治疗后2组患者均未见不良反应,并且肝肾功能正常。结论:桃红清血丸治疗气滞血瘀型白癜风安全、有效,其机制可能与调节机体细胞免疫功能有关。     

复方卡力孜然酊联合甲氧沙林片外用治疗白癜风42例临床研究

目的：研究复方卡力孜然酊联合甲氧沙林片外用治疗白癜风的疗效。方法：将本院2009年4～10月收治的69例白癜风患者随机分为治疗组42例和对照组27例,治疗组采用复方卡力孜然酊联合甲氧沙林片外用治疗,对照组采用复方卡力孜然酊外用治疗。结果：治疗组的疗效优于对照组,两组的不良反应发生率比较,差异无统计学意义。结论：复方卡力孜然酊联合甲氧沙林片外用治疗白癜风获得较佳疗效,且无严重不良反应,值得临床推广应用。     

Single-dose methoxsalen effects on human cytochrome P-450 2A6 activity.

Methoxsalen (8-methoxypsoralen) is an effective and selective mechanism-based inhibitor of human hepatic cytochrome P-450 (CYP)2A6 in vitro, and may have utility as a clinical probe for CYP2A6-catalyzed xenobiotic metabolism in humans in vivo. This investigation explored single-dose oral methoxsalen effects on human CYP2A6 activity in vivo, assessed by coumarin 7-hydroxylation. Eleven volunteers received 50 mg of oral coumarin on two occasions in a randomized crossover, 90 min after oral methoxsalen or nothing (controls). Plasma and urine 7-hydroxycoumarin and plasma methoxsalen concentrations were determined by HPLC. Methoxsalen pretreatment diminished area under the curve of plasma 7-hydroxycoumarin versus time by 24% (2.40 +/- 0.48 versus 3.20 +/- 0.55 microg. h. ml(-1); P <.001), and also decreased plasma 7-hydroxycoumarin C(max) (0.80 +/- 0.26 versus 1.4 +/- 0.5 microg/ml; P <.05); however, 7-hydroxycoumarin concentrations were only diminished 0.75 to 2 h after coumarin administration, but not thereafter. Methoxsalen diminished urine 7-hydroxycoumarin excretion in 0- to 1- and 1- to 2-h samples, but not thereafter, and total excretion was unchanged. Considerable individual variability in methoxsalen plasma concentrations was observed. There were significant correlations between the decrease in plasma 7-hydroxycoumarin C(max) and plasma methoxsalen C(max), but not between the decrease in plasma 7-hydroxycoumarin area under the curve and methoxsalen disposition. These results show that single-dose oral methoxsalen, in conventional doses, was a moderately effective inhibitor of human CYP2A6 activity in vivo, however, the duration of inhibition was limited. Interindividual variability in the extent of CYP2A6 inhibition appeared attributable to variability in the absorption and first-pass clearance of methoxsalen. Alternative doses, timing, and/or routes of methoxsalen administration are required for greater, longer, and more reproducible CYP2A6 inhibition than that provided by single-dose methoxsalen.     

Drug-drug interaction after single oral doses of the furanocoumarin methoxsalen and cyclosporine

Furanocoumarins increase the bioavailability of drugs that are CYP3A4 substrates. A possible interaction of methoxsalen with cyclosporine was evaluated in 12 healthy volunteers following oral administration of 40 mg methoxsalen, 200 mg cyclosporine, or a combination of both in a randomized crossover study. Methoxsalen increased area under the plasma concentration-time curve (AUC) and peak plasma concentration (Cmax) of cyclosporine by 29% (range, -20% to 172%; P < .05) and 8% (range, -10% to 26%; P < .05), respectively, compared to cyclosporine alone. The AUC geometric means ratio (95% confidence interval) for cyclosporine plus methoxsalen/cyclosporine alone was 1.14 (1.02, 1.27), and treatments were therefore not bioequivalent. Methoxsalen causes a clinically significant interaction with cyclosporine in some susceptible individuals. The reasons for susceptibility and the clinical implications for chronic cyclosporine administration have not been established. Caution is recommended in combination therapy, and more frequent monitoring of cyclosporine plasma levels and clinical monitoring is advised.     

Methoxsalen as an in vitro phenotyping tool in comparison with 1-aminobenzotriazole

1. The objective is to evaluate methoxsalen as an in vitro phenotyping tool in comparison to ABT as a nonspecific inactivator of P450 mediated metabolism.

2. The reversible inhibition of methoxsalen and ABT against the P450, FMO, AO, MAO-A and -B, enzymes were evaluated using standard marker probe reactions. The time-dependent inhibition of P450 enzymes was evaluated in human liver microsomes. CES1 activities were determined by monitoring the depletion of known substrate, the clopidogrel. The metabolism of P450 substrates in the presence and absence of methoxsalen or ABT was evaluated in human liver microsomes.

3. Methoxsalen is a direct inhibitor and inhibited the activities (>90%) of all enzymes at a concentration of 300?µM except for CYP2C9. Methoxsalen is also a potent time-dependent inhibitor of all P450 enzymes except for CYP2C19 (moderate) at a concentration of 300?µM. Methoxsalen inhibited the metabolism of P450 substrates in the pre-incubation mode. ABT is a potent TDI of several P450 except for CYP2C19 (47%) and CYP2C9 (27%).

4. The results indicate that methoxsalen is a potent pan P450 inhibitor than ABT and can be a better tool in distinguishing P450 mediated metabolism form non-P450 metabolism in human liver microsomes.

     

甲氧沙林脂质体凝胶的毒理学试验

目的：对甲氧沙林脂质体（LMOP）凝胶的毒理进行考察,以评价其生物安全性。方法：以豚鼠为实验动物,观察豚鼠完整皮肤及破损皮肤短时间接触LMOP凝胶后所产生的毒性反应情况以及单次与多次接触LMOP凝胶后所产生的局部刺激反应,并通过动物皮肤重复接触LMOP凝胶后,观察机体免疫系统在动物皮肤上的反应。结果：LMOP在豚鼠完整或破损皮肤局部均无明显刺激性及毒性,多次使用LMOP后,全身也无明显的毒性反应。结论：LMOP具有较高的皮肤应用安全性,值得进一步研究。     

HPLC法测定复方甲氧沙林洗剂中甲氧沙林和醋酸地塞米松的含量

目的：建立高效液相色谱法测定复方甲氧沙林洗剂中甲氧沙林和醋酸地塞米松的含量。方法：采用HPLC法,色谱柱：Sunfire C18（250 mm ×4.6 mm,5μm ）,流动相：乙腈-水（60∶40）,流速1.0 ml·min-1,检测波长：240 nm,柱温：30℃,进样量：20μl。结果：甲氧沙林和醋酸地塞米松分别在12.71~101.68 mg·L-1（r =0.9999）和10.03~80.25 mg·L-1（r =0.9997）范围内线性关系良好,平均回收率分别为99.32%（RSD=0.11%,n=9）和99.63%（RSD=0.20%,n=9）。结论：该法简便、准确、重复性好,可用于复方甲氧沙林洗剂中甲氧沙林和醋酸地塞米松的含量测定。     

Human halothane metabolism, lipid peroxidation, and cytochromes P 4502A6 and P 4503A4

OBJECTIVE: Halothane undergoes both oxidative and reductive metabolism by cytochrome P450 (CYP), respectively causing rare immune-mediated hepatic necrosis and common, mild subclinical hepatic toxicity. Halothane also causes lipid peroxidation in rodents in vitro and in vivo, but in vivo effects in humans are unknown. In vitro investigations have identified a role for human CYPs 2E1 and 2A6 in oxidation and CYPs 2A6 and 3A4 in reduction. The mechanism-based CYP2E1 inhibitor disulfiram diminished human halothane oxidation in vivo. This investigation tested the hypotheses that halothane causes lipid peroxidation in humans in vivo, and that CYP2A6 or CYP3A4 inhibition can diminish halothane metabolism. METHODS: Patients (n = 9 each group) received single doses of the mechanism-based inhibitors troleandomycin (CYP3A4), methoxsalen (CYP2A6) or nothing (controls) before a standard halothane anaesthetic. Reductive halothane metabolites chlorotrifluoroethane and chlorodifluoroethylene in exhaled breath, fluoride in urine, and oxidative metabolites trifluoroacetic acid and bromide in urine were measured for 48 h postoperatively. Lipid peroxidation was assessed by plasma F2-isoprostane concentrations. RESULTS: The halothane dose was similar in all groups. Methoxsalen decreased 0- to 8-h trifluoroacetic acid (23 +/- 20 micromol vs 116 +/- 78 micromol) and bromide (17 +/- 11 micromol vs 53 +/- 49 micromol) excretion (P < 0.05), but not thereafter. Plasma F2-isoprostanes in controls were increased from 8.5 +/- 4.5 pg/ml to 12.5 +/- 5.0 pg/ml postoperatively (P < 0.05). Neither methoxsalen nor troleandomycin diminished reductive halothane metabolite or F2-isoprostane concentrations. CONCLUSIONS: These results provide the first evidence for halothane-dependent lipid peroxidation in humans. Methoxsalen effects on halothane oxidation confirm in vitro results and suggest limited CYP2A6 participation in vivo. CYP2A6-mediated, like CYP2E1-mediated human halothane oxidation, can be inhibited in vivo by mechanism-based CYP inhibitors. In contrast, clinical halothane reduction and lipid peroxidation were not amenable to suppression by CYP inhibitors.     

The drug methoxsalen, a suicide substrate for cytochrome P-450, decreases the metabolic activation, and prevents the hepatotoxicity, of carbon tetrachloride in mice

Methoxsalen, a potent suicide inhibitor of cytochrome P-450 that can be used in humans, might be of value for the prevention of hepatitis in subjects with carbon tetrachloride poisoning. As a preliminary step, we have determined its effects on the hepatotoxicity of carbon tetrachloride in mice. Several monooxygenase activities, the in vitro covalent binding of carbon tetrachloride metabolites to microsomal proteins, and in vitro microsomal lipid peroxidation initiated by carbon tetrachloride metabolites were decreased by 60-90% in microsomes from mice killed 2 hr after the administration of methoxsalen (250 mumol X kg-1); microsomal lipid peroxidation mediated by endogenous iron and NADPH was not modified. Administration of methoxsalen (250 mumol X kg-1) 30 min before carbon tetrachloride (0.1 ml X kg-1) decreased both the in vivo formation of conjugated dienes in microsomal lipids and the in vivo covalent binding of carbon tetrachloride metabolites to lipids and proteins. This pretreatment completely prevented the hepatotoxicity of carbon tetrachloride. Other cytochrome P-450 inhibitors (cimetidine, SKF 525-A or piperonyl butoxide) given at this low molar dose (250 mumol X kg-1) exerted no protective effect. Methoxsalen (500 mumol X kg-1) was also effective, but only partially, when given 30 min after carbon tetrachloride (0.025 ml X kg-1). We conclude that pretreatment with methoxsalen decreases the metabolic activation of carbon tetrachloride, and completely prevents its hepatotoxicity in mice. Post-treatment with methoxsalen must be given early and is only partially effective in mice.