HPLC-荧光法测定人血浆中羟基喜树碱的两种构型及其相互间的转化

目的 建立高效液相色谱法(HPLC)测定人血浆中羟基喜树碱两种活性成分盐型羟基喜树碱(C-HCPT)和酯型羟基喜树碱(L-HCPT)含量的方法,并且对两者之间的相互转化进行了初步研究。方法 采用HPLC-荧光法,Lichrospher C₁₈色谱柱,流动相为乙腈-0.075 mol·L^-1醋酸铵缓冲液(32∶68,pH 6.4),流量1.0 ml·min^-1,检测器激发波长为363 nm,发射波长为530 nm,内标法计算药物浓度。结果 人血浆样品中C-HCPT、L-HCPT峰分离良好,内源性杂质不干扰样品峰,最低检测浓度均为5 ng·ml^-1。C-HCPT、L-HCPT浓度范围在15～2000 ng·ml^-1间呈线性相关,回归方程分别为Y₁=9.393×10^-4X₁-9.1×10^-6和Y₂=1.0207×10^-3X₂-3.4×10^-6,相关系数分别为r₁=0.9997和r₁=0.9998,相对回收率分别为96.79%～119.64%和100.23%～112.93%,日内和日间变异均小于10%。两者之间的转化具有一定规律性;C-HCPT标准血样-20℃冻存20 d稳定,L-HCPT标准血样的稳定性有待进一步研究。结论 本方法专属性强，灵敏、可靠，适用于HCPT 类制剂给药后血药浓度的监测和体内的药代动力学特征研究；有关两者相互转化的机制及L-HCPT 稳定性问题尚待进一步深入研究。     

RP-HPLC法测定注射用羟喜树碱脂质体含量

目的 建立测定注射用羟喜树碱脂质体含量的方法。方法 采用反相高效液相色谱法。色谱系统为ODS柱,以甲醇-水(60∶40)为流动相,检测波长为266 nm。结果 本品在5.886～10.930μg·ml^-1范围内呈线性关系,回归方程为:A=6.438×10⁴C-2.184×10⁴,r=0.9998。回收率为98.9%,RSD%为0.38(n=9)。结论 本法可测定注射用羟喜树碱脂质体中羟喜树碱的含量,方法快速、简便、准确。     

头序楤木叶中三萜化学成分的研究

从头序楤木(Aralia dasyphyla Miq)叶中分离到6个三萜化合物,用化学方法和波谱(UV,IR,MS,¹HNMR,¹³CNMR,¹³CDEPT,HMQC,HMBC)分析,确定其中4种化合物的结构,分别为齐墩果酸(I),16β-羟基-18β-H-齐墩果酸(I),齐墩果酸-28-O-β-D-吡喃葡萄糖甙(II)和16β-羟基-18β-H-齐墩果酸-28-O-β-D-吡喃葡萄糖甙(IV)。用NOESY谱确定化合物I的立体构型。以上4个化合物均为首次从该植物中分离到,化合物IV为新化合物。     

5α-△9(11)-16α-甲基-3β,17α,21-三羟基-孕甾烯-3β,21-双醋酸酯-20酮的微生物转化

简单节杆菌A₁及耻垢杆菌MS₁两种菌混合培养转化地塞米松中间体5α-△⁹⁽¹¹⁾-16α-甲基-3μ,17μ,21-三羟基-孕甾烯-3μ,21-双醋酸酯-20酮(Ⅲ)可得到16α-甲基-△^1.4.0(11)-孕甾烯-17α,21-双羟基-3,20双酮(Ⅳ)(65%收率)及少量的16α-甲基-△^1.4孕甾烯-9α,11α-环氧-17α,21双羟基-3,20双酮(Ⅴ)。     

桉叶苷的分离和结构

目的　研究垂枝赤桉Eucalyptus camaldulensis var. pendula Blak. et Jacobs叶的化学成分。方法　采用各种色谱技术进行分离纯化,用IR, MS, ¹HNMR, ¹³CNMR(DEPT), ¹H-¹H COSY, ¹³C-¹H COSY, COLOC和X-射线单晶衍射鉴定化合物。结果　分离得到了5个化合物：三十烷醇(I),β-谷甾醇(II),对羟基苯甲酸(III), 胡萝卜苷(IV), 5,7-二羟基-2-甲基-苯骈吡喃酮-7-O-β-D-{6-O-［4R-(1-甲基-1-羟基)-乙基环己-1-烯］-甲酰基}-吡喃葡糖(V)。结论　所有化合物均为首次从该植物中分得,V为一个新化合物,命名为桉叶苷(camaldulenside)。     

5α-△9(11)-16β-甲基-3β,17α,21-三羟基-孕甾烯-3β,21-双醋酸酯-20酮和5α,17α-甲基-17β-羟基-雄甾-3酮的微生物转化

用诺卡氏菌与节杆菌混合菌种转化从蕃麻皂素制得的中间体5α-△⁹⁽¹¹⁾-16-16β-甲基-3β,17α,21三羟基孕甾烯-3β,21-双醋酸酯-20酮(Ⅰ)得50%的16β-甲基-△^1,4,9(11)-孕甾三烯-20酮(Ⅱ)和少量的16β-甲基-9,11α环氧-△¹,4孕甾二烯-20酮(Ⅲ)。另外,又用同样的混合菌种转化从剑麻皂素制得的中间体5α,17α甲基-17β羟基-雄甾-3酮(Ⅳ)得50%17α甲基-17β羟基-△^1,4-雄甾二烯-3酮(Ⅴ)。如改变培养基则得3,17β-羟基-17α-甲基-9酮基-9,10开环-1,3,5(10)雄甾三烯化合物。     

HPLC法同时测定尿多酸肽注射液中4-羟基苯乙酸及5-羟基吲哚乙酸的含量

目的 以HPLC法同时测定尿多酸肽注射液中4-羟基苯乙酸及5-羟基吲哚乙酸的含量。方法 采用Mightysil RP-C₁₈(250mm×4.6mm,5μm)色谱柱,以1%的甲酸溶液为流动相A,乙腈为流动相B,梯度洗脱,柱温30℃,流量1ml·min^-1,检测波长282nm。结果 4-羟基苯乙酸在1.0～140.0μg·ml^-1范围内,色谱峰面积与对照品浓度呈现良好的线性关系,r=1.000;平均回收率为100.7%(RSD为0.6%,n=9)。5-羟基吲哚乙酸在0.1～20.0μg·ml^-1范围内,色谱峰面积与对照品浓度呈现良好的线性关系,r=1.000;平均回收率为99.7%(RSD为0.6%,n=9)。结论 该方法灵敏度高,准确,选择性、重复性好。     

白杨素衍生物的合成和晶体结构及与DNA的作用

以白杨素为先导化合物经羟甲基化反应合成中间体5,7-二羟基-6,8-二羟甲基黄酮(1)，进而合成了5,7-二羟基-6,8-二(甲氧基甲基)黄酮(2)，5,7-二羟基-6,8-二(乙氧基甲基)黄酮(3)，5,7-二羟基-6,8-二(丁氧基甲基)黄酮(4)，5,7-二羟基-6,8-二(戊氧基甲基)黄酮(5)和5-羟基-7-甲氧基-6,8-二(乙氧基甲基)黄酮(6)；采用IR，¹H NMR，¹³C NMR和元素分析对1～6进行了表征，同时用X-射线单晶衍射法对6进行了晶体结构测定。利用荧光法分别对1～4与CT-DNA的作用进行了研究，根据Stern-Volmer方程，它们对EB-DNA体系的荧光猝灭常数分别为k_q1=9.71×10³ L·mol^-1，k_q2=2.25×10⁴L·mol^-1，k_q3=1.03×10⁴L·mol^-1和k_q4=7.96×10³ L·mol^-1。1～4与白杨素相比，对DNA更具亲和力，为开发更有效的黄酮类化合物提供了实验依据。     

反相离子对色谱-荧光检测器同时检测两种形式的羟基喜树碱

目的 建立同时检测两种形式羟基喜树碱的反相离子对色谱-荧光检测器方法。方法 色谱柱:Kromasil ODS-C₁₈柱(4.6×250 mm,5μm);流动相:乙腈-0.075 mol·L^-1乙酸铵缓冲液(含0.005 mol·L^-1四丁基溴化铵,pH 6.4)(30∶70);流速:1.0ml·min^-1;柱温:30℃;检测器激发波长:363 nm,发射波长:550 nm。结果 羟基喜树碱内酯和羧酸盐的保留时间分别是5.118min和6.600 min,理论塔板数分别是4587和5410,分离度为3.803。结论 两种形式羟基喜树碱的保留时间、理论塔板数和分离度均达到了《中国药典》的要求,方法简单可靠。     

刺蒺藜果中一种新桂皮酰胺类成分的分离和鉴定

从刺蒺藜(Tribulus terrestris L)果实中分得两个化合物,经理化常数测定和光谱(UV,IR,¹HNMR,¹³CNMR,¹H-¹³CCOSY和MS)解析。化合物I鉴定为N-对羟基苯乙酮基-3-甲氧基-4-羟基取代桂皮酰胺,为一新化合物,命名为蒺藜酰胺(terrestriamide)。化合物II为8-甲基氢化茚酮-1,首次从该植物中获得。     

Lipid microencapsulation in starch

Short microwave heating of granular potato, waxy corn and tapioca starches with such lipids as cis-9-octadecenoic acid (oleic acid), cis,cis-9,12-octadecadienoic acid (linoleic acid), octadecanoic acid (stearic acid), ethyl cis-9-octadecenoate, ethyl cis,cis-9,12-octadecadienoate and methyl octadecanoate provided microcapsules in which encapsulated guest molecules did not interact with starch microcapsules. On the formation of microcapsules, the lipid guest molecules did not react to starches. The encapsulation yield varied between almost 11–94%.     

Role of Ascorbic Acid in Stratum Corneum Lipid Models Exposed to UV Irradiation

Purpose. The effects of ascorbic acid on Stratum corneum lipid models following ultraviolet irradiation were studied adding iron ions as transition metal catalysts. Methods. Lipid peroxidation was quantified by the thiobarbituric acid assay. The qualitative changes were studied on a molecular level by mass spectrometry. To elucidate the nature of free radical involvement we carried out electron paramagnetic resonance studies. The influence of ascorbic acid on the concentration of hydroxyl radicals was examined using the spin trapping technique. Moreover, we checked the vitamin's ability to react with stable radicals. Results. Ascorbic acid was found to have prooxidative effects in all lipid systems in a concentration dependent manner. The degradation products of ascorbic acid after its prooxidative action were detected. The concentration of the hydroxyl radicals in the Fenton assay was decreased by ascorbic acid. The quantification assay of 2,2-diphenyl-1-picrylhydrazyl hydrate showed reduced concentration levels of the stable radical caused by ascorbic acid. Conclusions. Considering human skin and its constant exposure to UV light and oxygen, an increased pool of iron ions in irradiated skin and the depletion of co-antioxidants, the administration of ascorbic acid in cosmetic formulations or in sunscreens could unfold adverse effects among the Stratum corneum lipids.     

Soraphen A, an inhibitor of acetyl CoA carboxylase activity, interferes with fatty acid elongation

Acetyl CoA carboxylase (ACC1 and ACC2) generates malonyl CoA, a substrate for de novo lipogenesis (DNL) and an inhibitor of mitochondrial fatty acid β-oxidation (FAO). Malonyl CoA is also a substrate for microsomal fatty acid elongation, an important pathway for saturated (SFA), mono- (MUFA) and polyunsaturated fatty acid (PUFA) synthesis. Despite the interest in ACC as a target for obesity and cancer therapy, little attention has been given to the role ACC plays in long chain fatty acid synthesis. This report examines the effect of pharmacological inhibition of ACC on DNL and palmitate (16:0) and linoleate (18:2, n − 6) metabolism in HepG2 and LnCap cells. The ACC inhibitor, soraphen A, lowers cellular malonyl CoA, attenuates DNL and the formation of fatty acid elongation products derived from exogenous fatty acids, i.e., 16:0 and 18:2, n − 6; IC₅₀ ∼ 5 nM. Elevated expression of fatty acid elongases (Elovl5, Elovl6) or desaturases (FADS1, FADS2) failed to override the soraphen A effect on SFA, MUFA or PUFA synthesis. Inhibition of fatty acid elongation leads to the accumulation of 16- and 18-carbon unsaturated fatty acids derived from 16:0 and 18:2, n − 6, respectively. Pharmacological inhibition of ACC activity will not only attenuate DNL and induce FAO, but will also attenuate the synthesis of very long chain saturated, mono- and polyunsaturated fatty acids.     

Inhibitory effect of N-nitro-

The effectiveness of mixed micelles in promoting nasal absorption of peptides has been demonstrated in vivo by employing insulin as a model compound. Insulin in the absence of adjuvants was not absorbed following intranasal administration. The results confirmed previous findings by others that absorption of insulin via alternative routes required absorption enhancers. Mixed micelles between NaGC and linoleic acid were found to rapidly deliver insulin into systemic circulation, with a concomitant decrease in plasma glucose. The extent of the hypoglycemic response was significantly greater than that produced by NaGC alone (55 vs 47%, P < 0.05). Emulsion of linoleic acid, on the other hand, did not produce any significant insulin absorption. The findings thus supported previous in situ data that mixed micelles were more effective than NaGC or linoleic acid in promoting nasal absorption of peptides. Histopathologic examination of the rat nasal mucosa revealed that the extent of morphological alterations caused by mixed micelles was of mild to moderate severity even after 5 hr of exposure. However, studies involving more frequent and prolonged exposures are necessary to assess the practicality of these adjuvants before any clinical application can be attempted.     

Bile Salt–Fatty Acid Mixed Micelles as Nasal Absorption Promoters of Peptides. II. In Vivo Nasal Absorption of Insulin in Rats and Effects of Mixed Micelles on the Morphological Integrity of the Nasal Mucosa

The effectiveness of mixed micelles in promoting nasal absorption of peptides has been demonstrated in vivo by employing insulin as a model compound. Insulin in the absence of adjuvants was not absorbed following intranasal administration. The results confirmed previous findings by others that absorption of insulin via alternative routes required absorption enhancers. Mixed micelles between NaGC and linoleic acid were found to rapidly deliver insulin into systemic circulation, with a concomitant decrease in plasma glucose. The extent of the hypoglycemic response was significantly greater than that produced by NaGC alone (55 vs 47%, P < 0.05). Emulsion of linoleic acid, on the other hand, did not produce any significant insulin absorption. The findings thus supported previous in situ data that mixed micelles were more effective than NaGC or linoleic acid in promoting nasal absorption of peptides. Histopathologic examination of the rat nasal mucosa revealed that the extent of morphological alterations caused by mixed micelles was of mild to moderate severity even after 5 hr of exposure. However, studies involving more frequent and prolonged exposures are necessary to assess the practicality of these adjuvants before any clinical application can be attempted.     

METABOLIC EFFECTS OF THIOCTIC ACID IN RODENT MODELS OF INSULIN RESISTANCE AND DIABETES

1. The antioxidant thioctic acid (TA) has been used in the treatment of diabetic neuropathy and recent studies have suggested that TA also has pancreatic and peripheral effects that improve glucose transport and metabolism. In the present study, the metabolic effects of TA were evaluated in rodent models of insulin resistance (fructose-fed Sprague-Dawley rat) and insulin deficiency (streptozotocin (STZ)-induced diabetic rat). Oral and intravenous glucose tolerance tests (OGTT and IVGTT, respectively) were performed in conscious rats after treatment with 50 mg/kg per day TA or vehicle for 5 days. 2. Fructose feeding for 7 days induced insulin resistance and impaired glucose tolerance and hypertriglycerideaemia. Treatment of fructose-fed rats with TA had no significant effect on fasting or stimulated glucose levels or on fasting triglyceride concentrations (e.g. the area under the curve for glucose (AUC_glu) following OGTT was 1233 ± 67 and 1284 ± 59 in fructose-fed rats treated with either TA (n= 12) or vehicle (n= 12), respectively). Similarly, TA had no significant effect on IVGTT profiles in fructose-induced insulin resistance. 3. Low-dose STZ (80 mg/kg, i.p, over 2 days) induced hyper-glycaemia, but TA had no significant glucose-lowering effects in STZ-diabetic rats (AUC_glu (OGTT) following oral administration was 5507 ± 27 and 5450 ± 27 in TA (n= 12) and vehicle-treated (n= 12) rats, respectively). Nor did pretreatment with TA affect the diabetogenic response to STZ. 4. In contrast with previous in vitro studies reporting favourable metabolic effects of TA, the present study shows that after short-term oral therapy there are no significant improvements in glucose tolerance in rodent models of insulin resistance and insulin deficiency. Thioctic acid is unlikely to be of therapeutic benefit as an anti-diabetic drug in clinical practice.     

Comparison of ozone-specific (OZAC) and oxygen radical (ORAC) antioxidant capacity assays for use with nasal lavage fluid

Antioxidants in respiratory mucus protect the underlying airway epithelium from damage by ozone (O₃), a common outdoor air pollutant. To understand O₃–antioxidant interactions and the variation of these interactions among individuals, in vitro assays are needed to measure the total antioxidant capacity of airway lavage fluid, a convenient source of (diluted) mucous samples. Here, we compare the oxygen radical absorbance capacity (ORAC), a general method that uses peroxyl radicals as a reactive substance, to the recently developed ozone specific antioxidant capacity (OZAC), a procedure that directly employs O₃. For prepared model mucous antioxidant solutions containing uric acid, ascorbic acid or glutathione, the ORAC and OZAC methods yielded comparable antioxidant capacities. The addition of EDTA or DETAPAC, necessary to prevent auto-oxidation of test solutions during the ORAC assay, unpredictably altered ORAC measurements. EDTA did not have a significant effect on OZAC measurements in either prepared uric acid or ascorbic acid solutions. When assessing antioxidant capacities of nasal lavage samples, the ORAC and OZAC assays were no longer comparable. Because the OZAC of nasal lavage samples was positively related to measured uric acid concentrations whereas the ORAC data were not, the OZAC method appears to provide more realistic mucous antioxidant capacities than the ORAC method.     

穆坪马兜铃化学成分的研究

自穆坪马兜铃(Aristolochia moupinensis Franch)根、茎中分得十三个化合物,其中化合物Ⅰ～Ⅻ经鉴定分別为马兜铃酸Ⅰ(aristolochic acid Ⅰ)(Ⅰ),尿囊素(allantoin)(Ⅱ),紫丁香酸(syringic acid)(Ⅲ),香豆酸(P-coumaric acid)(Ⅳ),马兜铃酸Ⅳ(aristolochic acid Ⅳ)(Ⅴ),β-谷甾醇(Ⅵ),木兰碱(magnoflorine)(Ⅶ),马兜铃酸Ⅳ甲醚aristolochic acid Ⅳmethyl ether(Ⅵ),棕榈酸(Ⅸ),马兜铃酸Ⅱ(aristolochic acid Ⅱ)(Ⅹ),N(Phydroxyphenethy1)P-coumaramide(Ⅺ),马兜铃酸Ⅳ甲醚甲酯(aristolochic acid Ⅳmethyl ether methyl ester)(Ⅻ),化合物ⅩⅢ为新化合物,经光谱分析和化学合成等方法证明其结构为N(P-hydroxyphenethyl)-ferulamide,命名为穆坪马兜铃酰胺(moupinamide)。初步药理试验表明穆坪马兜铃酰胺体外有抑制血小板聚集和影响血小板内前列腺素合成的作用。     

Safety and tolerability of prolonged-release nicotinic acid in statin-treated patients

ABSTRACT

Objective: To evaluate the safety and tolerability of prolonged-release nicotinic acid (Niaspan) added to statin therapy in patients at increased cardiovascular risk.

Methods: This was a 6-month, prospective, observa­tional, multicentre, open-label evaluation of prolonged-release nicotinic acid (maximum dose 2000?mg/day) in statin-treated patients with cardiovascular disease and/or type 2 diabetes. The primary endpoint was the safety and tolerability of prolonged-release nicotinic acid, with special regard to treatment-related adverse drug reactions (ADRs). Secondary endpoints were changes in lipids and 10-year cardiovascular risk (Prospective Cardiovascular Münster (PROCAM) score).

Results: The study population included 1053 patients: 50% had hypertension, diabetes and/or metabolic syndrome (National Cholesterol Education Program/Adult Treatment Panel III criteria) and 80% had cardiovascular disease. Flushing (mostly mild or moderate) occurred in 430 patients (40.8%). Other ADRs occurred in 125 patients (12.5%), most commonly pruritus (2.7%), gastro­intestinal symptoms (3.8%) and nervous system-related complaints (3.8%). Serious ADRs were uncommon (0.6%). All patients recovered completely from these ADRs after treatment discontinuation. In total, 11.1% of the patients discontinued study medication for flushing and 8.4% for other ADRs. There was no evidence of hepatotoxicity or myopathy. New-onset hyperglycaemia was negligible. Overall tolerability of prolonged-release nicotinic acid treatment (n = 734 patients at closeout) was ‘very good’ in 130 (17.7%), ‘good’ in 262 (35.7%), and ‘acceptable’ in 144 (19.6%) patients. High-density lipoprotein (HDL) cholesterol increased by 23%, triglycerides decreased by 15% and LDL-C decreased by 4%.

Conclusions: Prolonged-release nicotinic acid was safe and generally well tolerated and effective in combination with statin therapy in patients at high risk of cardio­vascular events, with a side-effect profile consistent with previous clinical experience.     

Pomegranate (<Emphasis Type="Italic">Punica granatum</Emphasis>) pure chemicals show possible synergistic inhibition of human PC-3 prostate cancer cell invasion across Matrigel™

Summary Four pure chemicals, ellagic acid (E), caffeic acid (C), luteolin (L) and punicic acid (P), all important components of the aqueous compartments or oily compartment of pomegranate fruit (Punica granatum), and each belonging to different representative chemical classes and showing known anticancer activities, were tested as potential inhibitors of in vitro invasion of human PC-3 prostate cancer cells in an assay employing Matrigel™ artificial membranes. All compounds significantly inhibited invasion when employed individually. When C, P, and L were equally combined at the same gross dosage (4 μ g/ml) as when the compounds were tested individually, a supradditive inhibition of invasion was observed, measured by the Kruskal-Wallis non-parametric test.An erratum to this article can be found at