Pharmaceutica acta Helvetiae最新文献_第6页

Excitatory amino acid agonists and antagonists: pharmacology and therapeutic applications 兴奋性氨基酸激动剂和拮抗剂:药理学和治疗应用

Pharmaceutica acta Helvetiae Pub Date : 2000-03-01 Epub Date: 2000-04-10 DOI: 10.1016/S0031-6865(99)00053-9

D.G Trist

{"title":"Excitatory amino acid agonists and antagonists: pharmacology and therapeutic applications","authors":"D.G Trist","doi":"10.1016/S0031-6865(99)00053-9","DOIUrl":"10.1016/S0031-6865(99)00053-9","url":null,"abstract":"<div>Glutamic acid is the major excitatory neurotransmitter in the mammalian central nervous system (CNS). Specific receptors bind glutamate and some of these when activated open an integral ion channel and are thus known as ionotropic receptors. Within the ionotropic family of glutamate receptors, three major subtypes have been identified using classical specific agonist activation, selective competitive antagonists together with their structural heterogeneity. These receptors have thus been named N-methyl-d-aspartate (NMDA), α-amino-3-hydroxy-5-methyl-4-isoxazole propionate (AMPA) and kainate receptors. The NMDA receptor has sites in addition to its agonist-binding site and these seem to either positively or negatively modulate the agonist effect. The NMDA receptor also is unique in that another amino acid, glycine, acts as a co-agonist with glutamate. Changes in glutamate transmission have been associated with a number of CNS pathologies; these include, acute stroke, chronic neurodegeneration, chronic pain, depression, drug dependency, epilepsy, Parkinson's Disease and schizophrenia.</div>","PeriodicalId":19830,"journal":{"name":"Pharmaceutica acta Helvetiae","volume":"74 2","pages":"Pages 221-229"},"PeriodicalIF":0.0,"publicationDate":"2000-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/S0031-6865(99)00053-9","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"21659338","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 68

Evaluation of solubility parameter to predict apparent solubility of amorphous and crystalline cefditoren pivoxil 预测非晶和结晶头孢地托林酯表观溶解度的溶解度参数评价

Pharmaceutica acta Helvetiae Pub Date : 1999-12-01 Epub Date: 2000-01-14 DOI: 10.1016/S0031-6865(99)00018-7

Masato Ohta , Toshio Oguchi , Keiji Yamamoto

{"title":"Evaluation of solubility parameter to predict apparent solubility of amorphous and crystalline cefditoren pivoxil","authors":"Masato Ohta , Toshio Oguchi , Keiji Yamamoto","doi":"10.1016/S0031-6865(99)00018-7","DOIUrl":"https://doi.org/10.1016/S0031-6865(99)00018-7","url":null,"abstract":"<div>The purpose of this study is to evaluate and predict the apparent solubility of cefditoren pivoxil in different crystallinity in terms of the two dimensional solubility parameters. The crystallinity of cefditoren pivoxil gradually decreased through grinding process. The partial solubility parameters, δd and δs relating to dispersion force interaction and other specific interaction, respectively, were calculated for the ground samples of cefditoren pivoxil using the inverse gas chromatography. The values of δd were constant independently regardless of the crystallinity, while the values of δs became greater with a decrease in the crystallinity of cefditoren pivoxil, suggesting that the polarity on the surface of cefditoren pivoxil powders could become higher. Interaction radius was calculated from the partial solubility parameters of cefditoren pivoxil and water. The dissolution study in water demonstrated that the concentration of cefditoren pivoxil at 20 min increased with decreasing in crystallinity. From these results, the improvement of dissolution by grinding should result from the change of the surface energetics relating to the polarity of cefditoren pivoxil by grinding. Further, the interaction radius could be also applied to predict the apparent solubility of crystalline cefditoren pivoxil in various organic solvents.</div>","PeriodicalId":19830,"journal":{"name":"Pharmaceutica acta Helvetiae","volume":"74 1","pages":"Pages 59-64"},"PeriodicalIF":0.0,"publicationDate":"1999-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/S0031-6865(99)00018-7","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"91742174","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 19

Influence of admixed lactose on pelanserin hydrochloride release from hydroxypropyl methylcellulose matrix tablets 混合乳糖对羟丙基甲基纤维素基质片中盐酸培兰色林释放的影响

Pharmaceutica acta Helvetiae Pub Date : 1999-12-01 Epub Date: 2000-01-14 DOI: 10.1016/S0031-6865(99)00020-5

Rogelio Espinoza-Ramos, Leopoldo Villafuerte-Robles

{"title":"Influence of admixed lactose on pelanserin hydrochloride release from hydroxypropyl methylcellulose matrix tablets","authors":"Rogelio Espinoza-Ramos, Leopoldo Villafuerte-Robles","doi":"10.1016/S0031-6865(99)00020-5","DOIUrl":"https://doi.org/10.1016/S0031-6865(99)00020-5","url":null,"abstract":"<div>Pelanserin, a weakly basic experimental drug with a short half-life, was taken as a model to study the influence of lactose on hydroxypropyl methylcellulose matrices to modulate a gradual release. Powder mixtures were wet-granulated with water and compressed in a hydraulic press at 55 MPa. Dissolution media were 900 ml HCl 0.1 N, the first 3 h and phosphate buffer pH 7.4, 3 to 8 h. Dissolution curves were described by Mt/Minf=ktn, applied separately for each dissolution medium. Dissolution mechanism involved diffusion/relaxation with a linear trend favoring the diffusion mechanism with increasing lactose concentrations. Increasing lactose concentrations produced higher kinetic constants, in a cubic relationship. A double HPMC proportion produced slower dissolution rates, with a more gradual lactose release but including certain degree of erosion. High lactose concentrations compensated for a decreased solubility of pelanserin at pH 7.4.</div>","PeriodicalId":19830,"journal":{"name":"Pharmaceutica acta Helvetiae","volume":"74 1","pages":"Pages 65-71"},"PeriodicalIF":0.0,"publicationDate":"1999-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/S0031-6865(99)00020-5","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"91742167","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 18

Influence of admixed lactose on pelanserin hydrochloride release from hydroxypropyl methylcellulose matrix tablets 混合乳糖对羟丙基甲基纤维素基质片中盐酸培兰色林释放的影响

Pharmaceutica acta Helvetiae Pub Date : 1999-12-01 DOI: 10.1016/S0031-6865(99)00020-5

Rogelio Espinoza-Ramos, L. Villafuerte-Robles

引用次数: 19

Evaluation of solubility parameter to predict apparent solubility of amorphous and crystalline cefditoren pivoxil 预测非晶和结晶头孢地托林酯表观溶解度的溶解度参数评价

Pharmaceutica acta Helvetiae Pub Date : 1999-12-01 DOI: 10.1016/S0031-6865(99)00018-7

M. Ohta, T. Oguchi, Keiji. Yamamoto

引用次数: 19

Poly(phthaloyl-l-lysine)-coated multilamellar vesicles for controlled drug delivery: in vitro and in vivo performance evaluation 用于控制药物递送的聚(邻苯二甲酰赖氨酸)包被多层囊泡:体外和体内性能评价

Pharmaceutica acta Helvetiae Pub Date : 1999-12-01 Epub Date: 2000-01-14 DOI: 10.1016/S0031-6865(99)00016-3

S.P Vyas, N Venkatesan

{"title":"Poly(phthaloyl-l-lysine)-coated multilamellar vesicles for controlled drug delivery: in vitro and in vivo performance evaluation","authors":"S.P Vyas, N Venkatesan","doi":"10.1016/S0031-6865(99)00016-3","DOIUrl":"10.1016/S0031-6865(99)00016-3","url":null,"abstract":"<div>Nonionic surfactant vesicles were prepared using Span 60, cholesterol and dicetyl phosphate. The prepared multilamellar vesicles (MLVs) were coated by interfacial polymerization technique using p-phthaloyl dichloride and l-lysine. The formation of the polymeric coat was confirmed by optical microscopic and transmission electron microscopic studies. The prepared, plain and polymer-coated MLVs were studied for their size, shape, encapsulation efficiency, in vitro release profile and effect of osmotic shock on vesicle. The results observed showed that the polymer-coated MLVs were stable under various osmotic conditions. In vivo studies were carried out on albino rats. The half-life and area under curve were found to be high in the case of polymer-coated MLVs as compared to plain MLVs and plain drug solution. In vivo studies using inflammed rat model also indicated that the polymer-coated MLVs were more stable and could release the drug in a controlled fashion as compared to plain MLVs.</div>","PeriodicalId":19830,"journal":{"name":"Pharmaceutica acta Helvetiae","volume":"74 1","pages":"Pages 51-58"},"PeriodicalIF":0.0,"publicationDate":"1999-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/S0031-6865(99)00016-3","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"21598675","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 16

Stability of l-asparaginase: an enzyme used in leukemia treatment l-天冬酰胺酶的稳定性:一种用于白血病治疗的酶

Pharmaceutica acta Helvetiae Pub Date : 1999-12-01 Epub Date: 2000-01-14 DOI: 10.1016/S0031-6865(99)00009-6

A.L Stecher , P Morgantetti de Deus , I Polikarpov , J Abrahão-Neto

{"title":"Stability of l-asparaginase: an enzyme used in leukemia treatment","authors":"A.L Stecher , P Morgantetti de Deus , I Polikarpov , J Abrahão-Neto","doi":"10.1016/S0031-6865(99)00009-6","DOIUrl":"10.1016/S0031-6865(99)00009-6","url":null,"abstract":"<div>l-asparaginase from Escherichia coli is an important enzyme widely used in leukemia treatment under the trade name Elspar®. Up to now, however, the aspects of its stability and storage has not been studied in detail. The aim of this work is to analyze the factors that could interfere in the enzyme's stability. The enzymatic activity was found to be stable in wide pH range (4.5–11.5), showing a slight increase in activity and stability in alkaline pHs, which indicates a more stable conformation of the molecule. The enzyme proved to have a high activity restoration capacity when submitted to temperatures of 65°C, in pH 8.6 buffer and, surprisingly, in physiologic solution. This suggests a positive effect of sodium ions on such restoration capacity. Stability was high in different diluents used as parenteral solutions and in recipients used in medical practice without significant loss of activity for at least 7 days. These results lead us to conclude that the enzyme has a high stability after the lyophilized form has been reconstituted (at least 7 days), since the necessary precautions are taken in terms of sterile manipulation and if it is stored in a suitable parenteral vehicle under low temperature (about 8°C).</div>","PeriodicalId":19830,"journal":{"name":"Pharmaceutica acta Helvetiae","volume":"74 1","pages":"Pages 1-9"},"PeriodicalIF":0.0,"publicationDate":"1999-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/S0031-6865(99)00009-6","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"21599972","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 103

Studies on antiplatelet agents from natural safrole 天然黄樟油抗血小板药物的研究

Pharmaceutica acta Helvetiae Pub Date : 1999-12-01 Epub Date: 2000-01-14 DOI: 10.1016/S0031-6865(99)00014-X

André L. de A. Reis , Cláudia B. Ormelli , Ana L.P. Miranda , Carlos A.M. Fraga , Eliezer J. Barreiro

{"title":"Studies on antiplatelet agents from natural safrole","authors":"André L. de A. Reis , Cláudia B. Ormelli , Ana L.P. Miranda , Carlos A.M. Fraga , Eliezer J. Barreiro","doi":"10.1016/S0031-6865(99)00014-X","DOIUrl":"https://doi.org/10.1016/S0031-6865(99)00014-X","url":null,"abstract":"<div>In an ongoing research program aiming at the synthesis and pharmacological evaluation of new possible prototype candidates exploring the molecular hybridation and bioisosterism principles for molecular designing, we describe in this paper the design and synthesis of a series of new functionalized oxime O-benzylethers (4a–b) and (14a–b) as antiplatelet agents based on the inhibition of arachidonic acid (AA) cascade enzymes. For the synthesis of these new bioactive derivatives we used safrole (5), a Brazilian abundant natural product, as starting material. The platelet anti-aggregating evaluation of these oxime O-benzylether compounds (4a–b) and (14a–b) in model induced by ADP, collagen and AA, has permitted to evidence an antithrombotic profile to these new derivatives, being the most active the derivative methyl [[3,4-methylenedioxyphenyl]methylene]amino]oxy]-4-methylenephenylacetic acid (14a).</div>","PeriodicalId":19830,"journal":{"name":"Pharmaceutica acta Helvetiae","volume":"74 1","pages":"Pages 19-28"},"PeriodicalIF":0.0,"publicationDate":"1999-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/S0031-6865(99)00014-X","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"91742175","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 7

Studies on controlled release dimenhydrinate from matrix tablet formulations 基质片中苯海明控释制剂的研究

Pharmaceutica acta Helvetiae Pub Date : 1999-12-01 Epub Date: 2000-01-14 DOI: 10.1016/S0031-6865(99)00017-5

Lütfi Genç, Hadi Bilaç, Erden Güler

引用次数: 38

Synthesis and preliminary binding affinities of 1-(1,2-dihydro-2-acenaphthylenyl)piperazine — a new arylpiperazine 新型芳基哌嗪- 1-(1,2-二氢-2-苊基)哌嗪的合成及初步结合亲和力

Pharmaceutica acta Helvetiae Pub Date : 1999-12-01 Epub Date: 2000-01-14 DOI: 10.1016/S0031-6865(99)00019-9

P Srinivas , P Brust , A.R Subramanian , S.A.V Raghavan , J.B Rangisetty , C.N.V.H.B Gupta , P Parimoo

引用次数: 0