HPLC法测定银杏达莫氯化钠注射液的含量

目的建立HPLC法测定银杏达莫氯化钠注射液中银杏总黄酮和双嘧达莫含量的方法。方法色谱柱:Diamonsil C18柱(4.6 mm×200.0 mm,5μm),流动相:甲醇-乙腈-30 mmol.L-1磷酸二氢钠溶液(体积比为20∶20∶80),检测波长:360 nm,测定3种黄酮苷元(槲皮素、山柰酚和异鼠李素);流动相:质量分数为0.1%的磷酸二氢钠溶液-甲醇(体积比为30∶70),检测波长:290 nm,测定双嘧达莫。结果槲皮素在0.01~0.09 g.L-1(r=0.999 3)、双嘧达莫在0.005~0.035 g.L-1(r=0.999 4)内呈良好的线性关系,平均回收率分别为102.5%(RSD=1.6%)、100.6%(RSD=1.1%)。结论本法可用于银杏达莫氯化钠注射液的质量控制。     

反相高效液相色谱法分别测定银杏达莫注射液中双嘧达莫与银杏总黄酮的含量

目的建立反相高效液相色谱测定银杏达莫注射液中的双嘧达莫和银杏总黄酮含量的方法。方法双嘧达莫采用Chromasil—C18（250mm×4．6mm，5μm）柱；流动相：0．1％磷酸二氢钠溶液．甲醇（25：75），检测波长为290nm，银杏总黄酮采用Shimpack-CLCODS（250mm×4．6mm，5μm）柱；流动相：0．4％磷酸溶液-甲醇（50：50），检测波长为360nm，流速为1．2ml／min。结果双嘧达莫进样浓度在6．12～24．48μg／ml范围内线性关系良好，平均回收率为99．82％，相对标准差（RSD）为0．85％；银杏总黄酮进样浓度在0．0476～0．1904mg／ml范围内线性关系良好，平均回收率为99．53％，RSD为0．69％。结论该法简便、快速、准确，可用于银杏达莫注射液的含量测定。     

复方双嘧达莫片的HPLC测定

建立高效液相色谱法测定复方双嘧达莫片中双嘧达莫及阿司匹林的含量.采用Ci8色谱柱,流动相为甲醇-水-磷酸-二乙胺(275:225:0.3:0.1),检测波长225nm.阿司匹林和双嘧达莫分别在6～14μg/mi和48～112ug/ml浓度范围内线性关系良好(r＞0.9995).平均回收率分别为98.0%(RSD=1.91%)和100.6%(RSD=1.50%).     

高效液相色谱法测定银杏内酯B滴丸的含量

目的建立银杏内酯B滴丸中银杏内酯B的含量测定方法。方法采用HPLC,选择Ec lipseXDB-C18(150mm×4.6mm,5μm)色谱柱,以甲醇-0.1%磷酸溶液(33.3∶66.7)为流动相;流速:1.0mL.m in-1;检测波长:225nm。结果银杏内酯B在0.2650~4.240mg.mL-1范围内线性关系良好(r=1.000);平均加样回收率为99.6%(RSD=1.3%)。结论此方法简便、快速、准确,可作为银杏内酯B滴丸的含量测定方法。     

苦丁茶老叶中槲皮素和山柰素的含量测定

目的:建立苦丁茶老叶中槲皮素和山柰素含量的HPLC测定方法。方法:色谱柱为Nova-Pak C18柱(3.9mm×300mm,4μm)柱,以甲醇-0.4%磷酸溶液(50∶50)为流动相,流速为0.7mL.m in-1,检测波长为360nm。结果:测定组分槲皮素、山柰素与其他组分的色谱峰基线分离;槲皮素加样回收率平均值为99.24%,RSD为1.60%,山柰素加样回收率平均值为98.77%,RSD为2.11%。结论:该方法样品处理简单,准确度高,分离效能好,适合于苦丁茶老叶中槲皮素和山柰素含量的测定。     

高效液相色谱法测定双嘧达莫的含量

目的:用高效液相色谱法(HPLC)测定双嘧达莫的含量.方法:十八烷基硅烷键合硅胶色谱柱,甲醇－0.1%磷酸二氢钠溶液(用1%的氢氧化钠调至pH 4.6)以3∶1为流动相,检测波长为283 nm.结果:线性范围9.94～49.7 μg&;#8226;mL 1,r＝0.999 9,平均回收率为101.82%,RSD为1.87%(n＝5).     

HPLC法测定双嘧达莫缓释片的含量

目的建立高效液相色谱法测定双嘧达莫缓释片的含量。方法采用EclipseXDBC18(Agi-lent,4.6mm×150mm,5μm)色谱柱。流动相为甲醇:水:磷酸:二乙胺(275:225:0.3:0.1);流量:1.0mL/min;检测波长:283nm;进样量:20μL。结果双嘧达莫在0.16～1.6μg范围内线性关系良好(r=0.9995),平均回收率为100.63%,RSD=0.35%(n=9)。结论本方法简便易行,结果准确可靠,专属性强,适用于双嘧达莫缓释片含量的测定。     

HPLC测定银杏达莫注射液中游离芦丁和槲皮素的含量

目的:建立反相高效液相色谱法测定银杏达莫注射液水解前芦丁、槲皮素的含量。方法:采用Zorbax Eclipse Plus C18柱(4.6 mm×150 mm,5μm),甲醇-0.4%磷酸溶液(38∶62)为流动相,流速1.0 mL.min-1,检测波长360 nm,柱温30℃。结果:芦丁、槲皮素分别在0.046675～4.6675μg、0.019927～1.9927μg之间线性关系良好,r=0.9999;平均回收率分别为98.9%,97.8%。结论:本方法有效、简便、精确,可用于银杏达莫注射液水解前芦丁、槲皮素的含量测定。     

HPLC法测定红花注射液中腺苷的含量

目的建立红花注射液的含量测定方法。方法 HPLC法采用Shim-Pack CLC-ODS柱,以甲醇∶0.1%枸橼酸溶液(45∶55)为流动相,检测波长246nm。结果在选定的色谱条件下,红花注射液在2.6～22μg/mL范围内,线性良好,平均回收率:99.60%,RSD为0.15%。结论该方法灵敏、结果准确、重复性好。     

复方双嘧达莫缓释片中双嘧达莫与阿司匹林含量的RP—HPLC测定

采用Kromasil-C18色谱柱,甲醇-0.1%磷酸二氢钠（用1：3磷酸调pH至4.6)(3:1)为流动相测定复方制剂中双嘧达莫和阿司匹林含量。UV检测波长为235nm,不经提取分离,溶解后直接进样检测。方法平均回收率为双嘧达莫101.74%,RSD为1.27%;阿司匹林101.76%,RSD为1.30%。     

Efficacy of gut lavage,hemodialysis, and hemoperfusion in the therapy of paraquat or diquat intoxication

Clinical and in vitro investigations were carried out to test the efficacy of gut lavage, hemodialysis, and hemoperfusion in the treatment of poisoning with paraquat or diquat. In a patient suffering from diquat intoxication 130 times more diquat was removed by gut lavage 30 h after ingestion than was removed by complete aspiration of the gastric contents.Determination of in vitro clearances for paraquat and diquat by hemodialysis showed that, at serum concentrations of 1–2 ppm, such as are frequently encountered in poisoning in man, toxicologically relevant quantities of herbicide cannot be removed from the body. At a concentration of 20 ppm, on the other hand, hemodialysis proved to be effective, the clearance being 70 ml/min at a blood flow rate of 100 ml/min. The efficacy of hemoperfusion with coated activated charcoal was on the whole better. Especially at concentrations around 1–2 ppm, the clearance values for hemoperfusion were some 5–7 times higher than those for hemodialysis.In a patient suffering from paraquat poisoning, both hemodialysis as well as hemoperfusion were carried out. The in vitro results could be confirmed: At serum concentrations of paraquat less than 1 ppm no clearance could be obtained by hemodialysis while by hemoperfusion with activated charcoal quite high clearance values were measured and the serum level dropped down to zero.

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Zusammenfassung Klinische Untersuchungen und Laboratoriumsversuche wurden durchgeführt, um die Wirksamkeit von Darmspülung, Hämodialyse und Hämoperfusion bei Paraquat- und Deiquat-Vergiftungen zu prüfen.Bei einem Patienten wurde 30 Std nach Deiquat-Aufnahme durch Darmspülung 130mal mehr Deiquat entfernt als durch vollständige Aspiration des Mageninhaltes. In vitro-Versuche ergaben, daß bei Blutserumkonzentrationen von 1–2 ppm, die bei Vergiftungen oft gemessen werden, durch Hämodialyse keine toxikologisch relevanten Paraquat- oder Deiquat-Mengen entfernt werden können. Dagegen erwies sich die Hämodialyse bei 20 ppm und einer Blutumlaufgeschwindigkeit von 100 ml/min mit einer Clearance von 70 ml/min als wirksam. Die Hämoperfusion mit beschicheter Aktivkohle war in diesen Versuchen aber eindeutig überlegen, denn insbesondere bei Konzentrationen um 1–2 ppm waren die Clearance-Werte 5–7mal höher als bei der Hämodialyse.Die in vitro-Ergebnisse wurden bei einem Patienten mit einer Paraquat-Vergiftung bestätigt: Bei Konzentrationen unter 1 ppm war die Hämodialyse wirkungslos, während durch Hämoperfusion relativ hohe Clearance-Werte erreicht wurden, so daß der Serumspiegel rasch unter die Nachweisgrenze abfiel.

     

Aquatic Insects and Trace Metals: Bioavailability,Bioaccumulation, and Toxicity

Abstract

The uptake of metals from food and water sources by insects is thought to be additive. For a given metal, the proportions taken up from water and food will depend both on the bioavailable concentration of the metal associated with each source and the mechanism and rate by which the metal enters the insect. Attempts to correlate insect trace metal concentrations with the trophic level of insects should be made with a knowledge of the feeding relationships of the individual taxa concerned. Pathways for the uptake of essential metals, such as copper and zinc, exist at the cellular level, and other nonessential metals, such as cadmium, also appear to enter via these routes. Within cells, trace metals can be bound to proteins or stored in granules. The internal distribution of metals among body tissues is very heterogeneous, and distribution patterns tend to be both metal and taxon specific. Trace metals associated with insects can be both bound on the surface of their chitinous exoskeleton and incorporated into body tissues. The quantities of trace meals accumulated by an individual reflect the net balance between the rate of metal influx from both dissolved and particulate sources and the rate of metal efflux from the organism. The toxicity of metals has been demonstrated at all levels of biological organization: cell, tissue, individual, population, and community. Much of the literature pertaining to the toxic effects of metals on aquatic insects is based on laboratory observations and, as such, it is difficult to extrapolate the data to insects in nature. The few experimental studies in nature suggest that trace metal contaminants can affect both the distribution and the abundance of aquatic insects. Insects have a largely unexploited potential as biomonitors of metal contamination in nature. A better understanding of the physico-chemical and biological mechanisms mediating trace metal bioavailability and exchange will facilitate the development of general predictive models relating trace metal concentrations in insects to those in their environment. Such models will facilitate the use of insects as contaminant biomonitors.     

Alzheimer’s disease – current trends in basic and clinical research. Highlights from the 16th ECNP

Advances in the molecular biological knowledge of neuronal nicotinic acetylcholine receptors (nAChRs) have led to a growing interest by the pharmaceutical industry in the development of novel compounds that selectively modulate nAChR function. The ability of (-)-nicotine, an activator of nAChRs, to enhance attentional aspects of cognition in animals and humans, to exert neuroprotective and anxiolytic-like effects, and presumably to mediate the negative correlation between smoking and Alzheimer's (and Parkinson's) Disease, has focused interest on the potential therapeutic utility of modulators of nAChR function for treatment of some of the deficits associated with these progressive, neurodegenerative conditions. Numerous compounds are known which activate nAChRs and which might serve as lead compounds toward the development of such agents. The pharmacologic diversity of neuronal nAChR subtypes suggests the possibility of developing selective compounds which would have more favourable side-effect profiles than existing agents. This broader class of agents, collectively called cholinergic channel modulators (ChCMs), is anticipated to encompass compounds which would have more favourable side-effect profiles than existing agents, which generally exhibit low selectivity. This selectivity may be achieved by preferentially activating some subtypes of nAChRs (i.e., Cholinergic Channel Activators, ChCAs) or inhibiting the function of other subtypes (Cholinergic Channel Inhibitors, ChCIs). An overview of the biology of nAChRs and the rationale for the use of ChCMs for the treatment of dementia related to neurodegenerative diseases are presented, followed by a discussion of lead compounds and compounds under consideration for clinical evaluation.     

2-(Acetoxyphenyl)-(Z)-styryl sulfides as cyclooxygenase inhibitors

2-(Acetoxyphenyl)-(Z)-styryl sulfides are described as selective cyclooxygenase-2 (COX-2) inhibitors, useful for treating inflammation and COX-2-mediated disorders including neoplasia. 2-(Acetoxyphenyl)-(Z)-styryl sulfide is claimed to be the most potent COX inhibitor in the series with a COX-2 selectivity ratio of 33. This compound is also claimed to be superior to celecoxib (Celebrex^®, Pfizer) in inhibiting cell growth of colorectal carcinoma cells. In this evaluation, the COX inhibitory activity of this compound is compared to that previously disclosed for diarylheterocycles and 2-(acetoxyphenyl)alkyl sulfides. The validity of the DLD-1 cell line in the growth inhibition studies is questioned based on recent literature reports indicating the lack of COX-2 expression in this cell line.     

Sleep-disordered breathing with chronic opioid use

Chronic opioid use for pain relief or as substitution therapy for illicit drug abuse is prevalent in our societies. In the US, retail distribution of methadone and oxycodone has increased by 824 and 660%, respectively, between 1997 and 2003. μ-Opioids depress respiration and deaths related to illicit and non illicit chronic opioid use are not uncommon. Since 2001 there has been an emerging literature that suggests that chronic opioid use is related to central sleep apnoea of both periodic and non-periodic breathing types, and occurs in ～ 30% of these subjects. The clinical significance of these sleep-related abnormalities are unknown. This review addresses the present knowledge of control of ventilation mechanisms during wakefulness and sleep, the effects of opioids on ventilatory control mechanisms, the sleep-disordered breathing found with chronic opioid use and a discussion regarding the future research directions in this area.     

Drug targets for cognitive enhancement in neuropsychiatric disorders

The investigation of novel drug targets for treating cognitive impairments associated with neurological and psychiatric disorders remains a primary focus of study in central nervous system (CNS) research. Many promising new therapies are progressing through preclinical and clinical development, and offer the potential of improved treatment options for neurodegenerative diseases such as Alzheimer's disease (AD) as well as other disorders that have not been particularly well treated to date like the cognitive impairments associated with schizophrenia (CIAS). Among targets under investigation, cholinergic receptors have received much attention with several nicotinic agonists (α7 and α4β2) actively in clinical trials for the treatment of AD, CIAS and attention deficit hyperactivity disorder (ADHD). Both glutamatergic and serotonergic (5-HT) agonists and antagonists have profound effects on neurotransmission and improve cognitive function in preclinical experiments with animals; some of these compounds are now in proof-of-concept studies in humans. Several histamine H3 receptor antagonists are in clinical development not only for cognitive enhancement, but also for the treatment of narcolepsy and cognitive deficits due to sleep deprivation because of their expression in brain sleep centers. Compounds that dampen inhibitory tone (e.g., GABA_A α5 inverse agonists) or elevate excitatory tone (e.g., glycine transporter inhibitors) offer novel approaches for treating diseases such as schizophrenia, AD and Down syndrome. In addition to cell surface receptors, intracellular drug targets such as the phosphodiesterases (PDEs) are known to impact signaling pathways that affect long-term memory formation and working memory. Overall, there is a genuine need to treat cognitive deficits associated with many neuropsychiatric conditions as well as an increasingly aging population.