米诺地尔凝胶的制备及质量控制

目的 :制备米诺地尔凝胶 ,建立其质量控制方法。方法 :以卡波姆934为基质制备凝胶 ,采用紫外分光光度法测定主药米诺地尔含量 ,并考察其稳定性。结果 :米诺地尔线性范围为2～10μg/ml(r=0. 9999) ,平均回收率为99.8 % ,RSD=0.67 % (n=4) ,凝胶稳定性良好。结论 :本处方设计合理 ,质量控制方法简便、准确、可行 ,制剂稳定性好。     

复方米诺地尔维A酸酊的制备及质量控制

目的制备复方米诺地尔维A酸酊并建立质量控制方法。方法以米诺地尔、维A酸、生姜、辣椒、月桂氮酮为组方,以75%乙醇为溶剂制备,采用高效液相色谱法分别测定其中的米诺地尔和维A酸含量。结果制剂为淡黄色至棕褐色的澄清液体,各项检查均符合2010年版《中国药典(二部)》附录ⅠC酊剂项下的各有关规定;米诺地尔检测质量浓度的线性范围为2.00～20.00μg/mL(r=0.999 8),平均回收率为99.53%,RSD为0.98%(n=9);维A酸检测质量浓度的线性范围为25.6～128.0μg/mL(r=0.999 9),平均回收率为99.83%,RSD为1.09%(n=9)。结论该制剂制备工艺简单,质量控制方法简便准确灵敏,专属性强,重现性好。     

复方米诺地尔溶液中米诺地尔的含量测定

目的　测定复方米诺地尔溶液中米诺地尔的含量,为该药提供质量控制指标。方法　采用紫外分光光度法,测定复方米诺地尔溶液中米诺地尔的含量。结果　米诺地尔浓度在1～5mg·L-1范围内吸收度与溶液浓度呈线性关系(r =0 . 9999,n =3) ,回收率为10 1. 0 % ,RSD为0 .34% (n =6 )。结论　该法能排除干扰,可作为复方米诺地尔溶液质量控制的有效方法之一。     

米诺地尔溶液的制备及其质量控制

目的:制备米诺地尔溶液,建立其含量测定方法.方法:通过紫外分光光度法,于286nm处测定米诺地尔含量.结果:在4～16μg·mL-1范围内,米诺地尔吸收度与浓度呈良好的线性关系,其回归方程为C(μg·mL-1)=17.40A-0.1051(γ=1.0000),平均回收率为99.8%(RSD为0.74%).结论:本方法操作简便、准确、可靠,可作为本品的质量控制.     

复方米诺环素过氧化苯甲酰洗剂的制备及质量控制

目的制备以米诺环素和过氧化苯甲酰为主药的复方外用洗剂,并建立其质量控制方法。方法采用紫外分光光度法测定米诺环素的含量,测定波长352nm;间接碘量法测定过氧化苯甲酰的含量。结果米诺环素的检测线性范围为4~24μg.mL-1,r=0.9998,平均回收率为100.2%;过氧化苯甲酰的平均回收率为99.6%,RSD为0.6%(n=6)。结论该制剂制备工艺简单、质量稳定,质量控制方法可行。     

高效液相色谱法测定盐酸米诺环素胶囊及片剂的溶出度

目的:建立测定盐酸米诺环素胶囊及片剂溶出度的高效液相色谱法.方法:采用桨法,以水为溶剂,转速为50r/min,45 min取样滤过,进样.Kromasil C8柱(4.6 mm×250 mm,5μm),以0.2 mol/L醋酸铵:N,N-二甲基甲酰胺:四氢呋喃(600:398:2,内含0.01 mol/L乙二胺四乙酸二钠)为流动相,检测波长为280 nm.结果:盐酸米诺环素线性范围是0.10～2.00mg/mL,r=0.999 9.平均回收率盐酸米诺环素胶囊为98.6%,RSD为1.4%(n=9),盐酸米诺环素片剂为98.8%,RSD为1.2%(n=9).结论:该方法简便、准确、灵敏度高,能有效控制产品质量.     

盐酸米诺环素膜剂的制备与质量控制

目的:制备盐酸米诺环素膜剂并制定该制剂的质量控制方法。方法:以聚乙烯醇（PVA 17-88）;羧甲基纤维素钠（CMC-Na）为成膜材料,制备盐酸米诺环素膜剂,采用高效液相色谱法进行含量测定,测定波长为280nm。结果:盐酸米诺环素浓度测定的线性范围为0.1～2.0mg·ml^-1,r=0.9999（n=7）,平均回收率为98.88%,RSD为0.88%。结论:该膜剂制备工艺可行,含量测定方法准确快速。     

紫外分光光度法测定米诺地尔洗剂中米诺地尔的含量

目的建立米诺地尔洗剂的含量测定方法.方法采用紫外分光光度法测定洗剂中米诺地尔的含量.结果测定波长231 nm,在1～7 μg/ml浓度范围内吸收度与浓度线性关系良好(r=0.9998),平均回收率99.29%,RSD 0.05%(n=4).结论本法方便快捷,结果准确,可用于米诺地尔洗剂的质量控制.     

浊度法测定盐酸米诺环素原料及其片剂的效价

目的 建立浊度法测定盐酸米诺环素原料及其片剂效价的方法.方法 :以金黄色葡萄球菌为实验菌,加菌量2.0%～4.0%(V/V),37 ℃±0.5 ℃培养约4 h测定.结果 :抗生素线性浓度为0.03～0.10 μg·mL-1,原料二剂量法的平均回收率为99.42%,RSD为2.1%(n=9);片剂二剂量法的平均回收率为100.22%,RSD为1.9%(n=9).结论 :本方法灵敏,快速,影响因素较少,可作为测定盐酸米诺环素原料及其片剂的效价的方法.     

离子色谱法测定米诺膦酸及其片剂的含量

目的：建立离子色谱法测定米诺膦酸及其片剂中米诺膦酸的含量。方法：采用IonPac AS23阴离子交换色谱柱分离,淋洗液为3 mmol.L^-1草酸溶液,流速为1.0 mL.min^-1,柱温为30℃,进样量为25 μL,检测方式为电导检测器。结果：米诺膦酸在9.50~380.08 μg.mL^-1范围内线性关系良好(r=1.0000);原料药和片剂的平均加样回收率分别为101.0%(RSD为0.4%,n=9)和98.8%(RSD为1.2%,n=9)。结论：该方法准确、灵敏、简便,可用于米诺膦酸原料药及其制剂中米诺膦酸的含量测定。     

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.