bluuebunny/crossref_metadata_2025_split huggingface dataset:
Effect of fenugreek seeds on intravenous glucose disposition in non‐insulin dependent diabetic patients
Authors: Raghuram T. C. , Sharma R. D. , Sivakumar B. , Sahay B. K. 
Published: October 2006

AbstractThe hypoglycaemic activity of fenugreek seeds (Trigonella foenum graecum) in experimental animals and humans has been well documented. Fenugreek has been shown to reduce fasting and postprandial blood glucose levels in diabetic patients. However, it is not clear whether the improvement in glucose tolerance is due to the effect of fenugreek on the absorption or metabolism of glucose. A metabolic study was carried out, and diets with or without 25 g fenugreek were given randomly to 10 non‐insulin dependent diabetics, each for 15 days, in a crossover design. An intravenous glucose tolerance test (GTT) at the end of each study period indicated that fenugreek in the diet significantly reduced the area under the plasma glucose curve (AUC), half‐life, and increased the metabolic clearance rate. In addition, it increased erythrocyte insulin receptors. These results suggest that fenugreek can improve peripheral glucose utilization which contributes to an improvement in glucose tolerance. Thus, fenugreek may exert its hypoglycaemic effect by acting at the insulin receptor as well as at the gastrointestinal level.
Volatile constituents of Xylopia frutescens, X. pynaertii and X. sericea: Chemical and biological study
Authors: Fournier G. , Hadjiakhoondi A. , Leboeuf M. , Cavé A. , Charles B. , Fourniat J. 
Published: October 2006

AbstractThe essential oils from three Xylopia species (X. frutescens, X. pynaertii, X. sericea), Annonaceae, have been examined by GC and GC/MS, and screened for bacteriostatic and fungistatic activities. The main components of each oil have been identified. The major constituents of X. frutescens stem bark oil were α‐cubebene (25.2%) and δ‐cadinol (27.4%). The root of X. pynaertii was rich in elemol (27.1%), while the stem bark oil contained δ‐cadinene (10.3%), γ‐muurolene (10.1%) and cubenol (12.6%). The major components of X. sericea root bark oil were p‐cymene (22.8%) and α‐gurjunene (13.8%). These oils exhibited moderate bacteriostatic and fungistatic activities.
Antiulcer effect of flavonoids. Role of endogenous PAF
Authors: Izzo A. A. , Carlo G. Di , Mascolo N. , Capasso F. , Autore G. 
Published: October 2006

AbstractQuercetin, rutin and kaempferol, administered intraperitoneally (25–100 mg/kg) inhibited dose‐dependently gastric damage produced by acidified ethanol in rats. Flavone was inactive while naringin was active at higher dose (200 mg/kg). The flavonols tested inhibited dose‐dependently the mucosal content of platelet‐activating factor (PAF) suggesting that the protective effects of these substances may be mediated by endogenous PAF.
Hepatoprotective studies of a fraction from the fruits of Terminalia belerica roxb. On experimental liver injury in rodents
Authors: Anand K. K. , Singh B. , Saxena A. K. , Chandan B. K. , Gupta V. N. 
Published: October 2006

AbstractThe effects of an orally administered fraction (TB5) from the fruits of Terminalia belerica in experimental liver injury induced by carbon tetrachloride (CCI4) were studied. Hexobarbitone‐induced sleep, zoxazolamine‐induced paralysis, transaminases, bilirubin, total protein in serum and microsomal lipid peroxidation and triglycerides in liver were used as indices of liver injury.A significant hepatoprotective effect was observed as evident from shortened hexobarbitone ‘sleep time’ and zoxazolamine ‘paralysis time’ when compared with CCI4 alone. Pre‐ and post‐treatment of TB5 reduced, in a dose dependent manner, the elevated levels of serum tranaminases and bilirubin in rats, thus demonstrating its effect both as a prophylactic and curative. Its protective effects on microsomal lipid peroxidation and triglycerides in liver suggest a restorative effect in the process of CCI4‐induced liver damage. TB5 did not show any signs of toxicity up to oral doses of 3.2 g/kg in mice.
Semi‐synthesis of C203H‐resiniferatoxin
Authors: Gordge Phil C. , Darcy Patricia , Evans A. Tudor , Ryves W. Jonathan , Evans Fred J. , Hassan Nahed M. 
Published: October 2006

AbstractThere has recently been considerable interest concerning the biochemical and pharmacological mechanisms of action of resiniferatoxin (Rx). Rx is a daphnane diterpene ester, which is part of the phorbol ester family of diterpenes. We have synthesized 3H‐Rx in a three‐step process from the parent alcohol, resiniferonol (Ro). The tritium label is incorporated into the resiniferonol nucleus at the C20 position, before esterification of 3H‐Ro to 3H‐Rx. This compound will be of use in the elucidation of the binding characteristics of Rx to its biochemical receptor site(s).
Garlic compounds protect vascular endothelial cells from hydrogen peroxide‐induced oxidant injury
Authors: Yamasaki Takeshi , Li Lin , Lau Benjamin H. S. 
Published: October 2006

AbstractOxygen radical injury and lipid peroxidation have been suggested as major causes of cancer, atherosclerosis and the aging process. In this study, we determined in vitro the effect of aged garlic extract (AGE) and one of its components, S‐allyl cysteine (SAC), on hydrogen peroxide (H2O2)‐induced oxidant injury using bovine pulmonary artery endothelial cells (PAEC). After overnight preincubation with AGE or SAC, PAEC monolayers were exposed to H2O2 for 3 h. Cell viability, lactate dehydrogenase (LDH) release and lipid peroxidation were measured to assess oxidant injury. Pretreatment with AGE at 2–4 mg/mL or SAC at 4 mg/mL significantly reversed the loss of cell viability induced by 50 and 100 μm of H2O2. AGE or SAC also exhibited a dose‐dependent inhibition of both LDH release and lipid peroxidation induced by 50 μM of H2O2. The results show that both AGE and SAC can protect vascular endothelial cells from oxidant injury. The data thus suggest that these compounds may be useful for retardation of the aging process and for prevention of cancer and atherosclerosis.
Flavonoid treatment reduces glycation and lipid peroxidation in experimental diabetic rats
Authors: Vertommen J. , van den Enden M. , Simoens L. , de Leeuw I. 
Published: October 2006

AbstractIt has been reported that flavonoids in vitro have the capacity to inhibit aldose reductase. The aim of this study was to evaluate this property in vivo. We chose diosmin, a freely available and inexpensive flavonoid without major side effects. Streptozotocin diabetic rats were treated for a period of 8 months with diosmin, mixed with their food. Sorbitol accumulation was measured in erythrocytes and in eye lenses. In these tissues diosmin did not appear to inhibit aldose reductase.However, diosmin‐treated animals maintained a greater body weight than the untreated group. Although the glycaemic values were the same, and the insulinaemias even lower in the diosmin group, glycated haemoglobin was significantly decreased compared with the untreated animals. Skin collagen fluorescence, an index of collagen glycation, was also significantly decreased in the treated animals. Malondialdehyde, a stable end product of lipid peroxidation, was decreased in the treated animals. Diosmin was well tolerated by the animals.In conclusion, diosmin is a safe and inexpensive product. It cannot inhibit aldose reductase activity in vivo but diosmin causes a significant reduction of the glycation of proteins in diabetic animals. Inhibition of lipid peroxidation is also observed but it is not clear whether or not this phenomenon is a direct consequence of the decreased glycation.
Pharmacological properties of Visnea mocanera L. f. extracts: Screening for analgesic, antipyretic, antiinflammatory and ulcerogenic activities in rodents
Authors: Hernández‐Pérez M. , Sánchez‐Mateo C. C. , Darias V. , Rabanal R. 
Published: October 2006

AbstractDifferent extracts of Visnea mocanera L. f. (Theaceae) were evaluated for analgesic, antipyretic, antiinflammatory and ulcerogenic properties in mice and rats. The acetone extract from the leaves and the syrup from the fruits exerted central analgesic properties, associated with significant but transient antiinflammatory effects on acute inflammatory processes. The acetone extract also possessed topical antiinflammatory effects. The extracts assayed did not display antipyretic and ulcerogenic activity. Sub‐acute toxicological experiments indicated a very low toxicity in mice.
In vitro antiplasmodial effects of diospyrin, a plant‐derived naphthoquinoid, and a novel series of derivatives
Authors: Hazra Banasri , Ghosh Rina , Banerjee Amalendu , Kirby Geoffrey C. , Warhurst David C. , Phillipson J. David 
Published: October 2006

AbstractSynthesis of derivatives of diospyrin, a natural product, has led to the modification of its tumour‐inhibitory effect, in vitro, towards Ehrlich ascites carcinoma and antiparasitic activity against Leishmania donovani in vitro. The present study shows that two of these novel hydroquinoid analogues derived from diospyrin also show enhanced inhibitory effects against Plasmodium falciparum, in vitro, and may be a useful model for the development of novel antimalarial drugs.
Inhibition of tumour‐promoter‐enhanced 32Pi‐incorporation into cellular phospholipids by flavonols from genus Chrysosplenium
Authors: Arisawa Munehisa , Shimizu Mineo , Satomi Yoshiko , Nishino Atsuko , Nishino Hoyoku , Iwashima Akio 
Published: October 2006

AbstractFlavonol aglycones from the genus Chrysosplenium showed potential antitumour‐promoter activity. Three flavonols, oxyayanin A and chrysosplenols D and E, markedly inhibited the incorporation of 32Pi into phospholipids of confluent HeLa cells stimulated by 12‐O‐tetradecanoylphorbol‐13‐acetate (TPA), a potent tumour promoter. The potency of the flavonols proved to be similar to those of other antitumour‐promoting flavonoids.
A microbiological evaluation of medicinal plants used by the Maya people of Southern Mexico
Authors: Meckes Mariana , Villarreal Ma. Luisa , Tortoriello Jaime , Berlin Brent , Berlin Eloise Ann 
Published: October 2006

AbstractA microbiological evaluation was conducted on those medicinal plants most frequently used to treat gastrointestinal and respiratory diseases by Tzeltal and Tzotzil communities in the highlands of Chiapas. The results obtained showed that many of the species induced antimicrobial activity in vitro. The present study allowed selection of three groups of plants with potent effect against gram‐positive Staphylococcus aureus, gram‐negative Escherichia coli bacteria and Candida albicans. It was also demonstrated that 63% of the botanical species that showed antimicrobial properties, enhanced (46%) or induced (17%) the effect under exposure of the plant extracts to UV‐A light. In the search for new molecules with therapeutic value, the present screening offers a preliminary selection of groups of botanical species; within each, there are several representatives that merit further evaluation as potential antibiotics and photosensitizers.
Smooth muscle relaxant activities of compounds isolated from malaysian medicinal plants on rat aorta and guinea‐pig ileum
Authors: Mustafa Mohd. Rais , Mohamad Rohaini , Din Laily , Wahid Shamsuddin 
Published: October 2006

AbstractMuscle relaxant activities of six compounds isolated from Malaysian medicinal plants were investigated on the smooth muscles of the rat aorta and longitudinal muscle of the guinea‐pig ileum. Except for goniothalamin, the other five compounds exhibited varying degrees of muscle relaxant activities on the two smooth muscles. Dicentrine, isocorydine, altholactone and usnic acid reduced the contractions to KCI and phenylephrine in the rat aorta, whilst atranorin slightly reduced the contractions to phenylephrine but not KCI. In addition, dicentrine and isocorydine markedly reduced the contractile response to phenylephrine in Ca2+‐free Krebs solution. In the longitudinal muscle of the guinea‐pig ileum, altholactone, atranorin, dicentrine and isocorydine inhibited to a greater extent the phasic than the tonic responses to KCI. All four compounds similarly inhibited the contractions induced by ACh. The results suggest that the relaxant activities of the compounds are attributed mainly to inhibition of Ca2+ influx via the calcium channels in the membrane of the smooth muscles. Furthermore, the greater sensitivity of dicentrine, isocorydine and altholactone against phenylephrine‐induced contractions or KCI‐induced phasic contractions are due to their abilities to inhibit intracellular Ca2+ release in these muscles.
General Treatment of Heteroatoms with the Randic Molecular Connectivity Index
Authors: Kupchik Eugene J. 
Published: October 2006

AbstractExcellent structure‐molar refraction relationships of alkylphosphines, dialkyl sulfides, alkylthiols, alkylamines, dialkyl ethers, and aliphatic alcohols were obtained using the Randic molecular connectivity index. Excellent structure‐molar refraction relations were also obtained using two empirically‐modified connectivity indices which reflect either the difference in bond length between the heteroatom‐carbon bond and a carbon‐carbon bond or the difference in covalent radius between the heteroatom and a carbon atom. Use of the empirically‐modified indices improves the prediction of molar refraction for a mixed set of alkylphosphines, dialkyl sulfides, alkylthiols, alkylamines, dialkyl ethers, aliphatic alcohols, alkanes, alkylsilanes, alkylgermanes, and alkyl halides.
Comparison of Fragment Weighting Schemes for Substructural Analysis
Authors: Ormerod Ann , Willett Peter , Bawden David 
Published: October 2006

AbstractSeveral methods have been described in the literature for the calculation of weights which represent the contribution of fragments to the overall activity or inactivity of molecules which contain them. These weighting schemes are based on fragment occurrence data in training sets of molecules for which the activity is known. This paper reports a comparison of several such schemes (fourteen fragment weights in all), using small datasets for which structural and activity data are available. The comparison reveals that the most effective weight seems to be one derived from research into document retrieval systems (where indexing terms are used to discriminate between relevant and non‐relevant documents).
Structure‐Activity Models for Molar Refraction of Alkylsilanes Based on Molecular Connectivity
Authors: Hall Lowell H. , Aaserud David 
Published: October 2006

AbstractStructure‐activity models are established using molecular connectivity indexes for the molar refraction of 115 alkylsilanes containing 10 monoalkyl‐, 14 dialkyl‐, 32 trialkyl‐and 59 tetraalkylsilanes. In the model based only on 1χ, r = 0.997, s = 1.47, F = 20367. For the two indexes, 1χ and 2χv, r = 0.9987, s = 1.020 and for the three‐variable model based on 0χv, 1χ and 2χv, r = 0.9994, s = 0.664. The quality of these models, based on the Kier‐Hall valence delta formalism, suggests the adequacy of that formalism in encoding the atomic characteristics of silicon in this data set. As a further test of the formalism, a mixed data set of 46 alkylsilanes, 46 alkanes and 41 chloroalkanes was investigated. For the same three indexes, 0χv, 1χ and 2χv, r = 0.9996, s = 0.369. To reduce the intercorrelation between the two low order chi indexes, a linear transformation of these variables is introduced. The sum of a simple and valence index is used in place of the indexes themselves. The quality of the correlations is essentially the same using these sum variables. These results are compared to a proposed empirical modification of the valence delta for alkylsilanes.
Topological Indices in Correlation Analysis. Part 2. Molecular Shape Indices in Modelling of the Chromatographic Retention Parameters
Authors: Mokrosz Jerzy L. , Duszyńska Beata 
Published: October 2006

AbstractDifferent chromatographic data sets for hydrocarbons, alcohols, aldehydes, ketones, esters and barbiturates picked up from the literature were correlated with the kappa molecular shape indices. All correlations were statistically highly significant. Application of the kappa indices in such modelling is discussed.
Hydrophobicity Parameter of Diazines (1) Analysis and Prediction of Partition Coefficients of Monosubstituted Diazines
Authors: Yamagami Chisako , Takao Narao , Fujita Toshio 
Published: October 2006

AbstractThe octanol/water partition coefficient (P) of a number of monosubstituted diazines was measured. The composition of the π value of substituents, the increment in the logP value accompanied with the introduction of substituents, was examined in terms of physicochemical substituent parameters and correlation analysis. The diazine‐π value of substituents was generally higher than the pyridine‐π value of corresponding substituents, indicating that the intramolecular electronic interactions between the ring‐N atoms and substituent are more pronounced than those in substituted pyridines in governing the logP value of the molecule. Except for 2‐substituted pyrimidines, the π value of substituents in each series of monosubstituted diazines was in general nicely correlated with the π value of the corresponding substituents in substituted pyridines along with electronic parameter terms representing “bidirectional” electronic effects on the relative solvation of the ring‐N atom(s) and the hydrogen‐bondable substituents with partitioning solvents according to the procedure proposed previously for the analysis of the π value in disubstituted benzenes and monosubstituted pyridines. Keeping in mind that 2‐pyrimidines substituted by hydrogen‐bondable groups sometimes behave as outliers, the correlations were believed to be usable for prediction of logP value of monosubstituted diazines.
A Strategy for Ranking Environmentally Occurring Chemicals. Part IV: Development of Chemical Model Systems for Characterization of Halogenated Aliphatic Hydrocarbons
Authors: Lindgren Fredrik , Eriksson Lennart , Hellberg Sven , Jonsson Jörgen , Sjöström Michael , Wold Svante 
Published: October 2006

AbstractEight chemical model systems were developed for a multivariate physicochemical characterization of halogenated aliphatics. The chemical model systems were developed to obtain descriptors which contained information related to lipophilicity and chemical reactivity of the studied compounds. A selected set of 15 halogenated aliphatic compounds were characterized by the chemical model systems. The information content in eight new descriptors combined with eight old physico‐chemical descriptors were validated in a QSAR. The used biological responses were acute oral toxicity to rat, highest non‐lethal dose to mouse and in vitro genotoxicity from a DNA precipitation assay. This model was compared with a QSAR based on eight old‐physico‐chemical descriptors. It was found that the addition of the new descriptors improved the QSAR.
Theoretical Determination of the Putative Receptor‐bound Conformations of 5‐HT2 Receptor Agonists
Authors: Höltje Hans‐Dieter , Briem Hans 
Published: October 2006

AbstractFor a series of compounds with agonistic activity at the 5‐HT2 receptor a pharmacophoric model was established. It has been shown by means of conformational analyses and molecular electrostatic potential calculations that the pharmacophores of all active compounds can adopt common positions at the receptorsite. Besides our model offers an explanation for the stereoselectivity of the chiral compounds as well as for the complete loss of activity of a phenylethylamine compound containing an α,α‐dimethyl sidechain.
Prediction of Mammalian Toxicity by Quantitative Structure Activity Relationships: Aliphatic Amines and Anilines
Authors: Jäckel Hannelore , Klein Werner 
Published: October 2006

AbstractQuantitative Structure‐Activity Relationships (QSARs) are derived to predict oral toxicity data of aliphatic amines and anilines for rats. LD50‐values from the RTECS data base are correlated to 1‐octanol/water partition coefficient (logPow), fragment‐values and electronic properties. Toxicity data of aliphatic monoamines are sufficiently described by a bilinear logPow‐dependent equation, consideration of polyamines requires a fragment‐descriptor reflecting the polyfunctionality. Toxicity data of anilines are best predicted by a combination of electronic, steric and hydrophobic parameters.The validity of the developed models is compared with known QSARs.
Single Class Discrimination Using Principal Component Analysis (SCD‐PCA)
Authors: Rose Valerie S. , Wood John , Macfie Halliday J. H. 
Published: October 2006

AbstractSingle Class Discrimination using Principal Component Analysis (SCD‐PCA) has been developed to discriminate an embedded data class. The embedded class is defined as the active class and the diffuse class, or classes as the inactives. Two basic methods are described. Both involve an initial column centring and scaling of the data to the actives space. Method I then directly obtains the directions of maximum variance in the inactives by PCA, while method II attempts to maximize the ratio of inactives to actives variance using PCA. The methods offer good potential to reveal a tightly bedded active class near the origin with the inactives dispersed. Techniques to portray the discrimination power and significance of the PCs are discussed. SCD‐PCA has been applied to artificial data sets exhibiting a variety of distributional characteristics and to two QSAR data sets. The method performed predictably on the artificial data. Good, low dimensional PC models were obtained for the QSAR data sets which were stable when cross‐validated.
A Linear Molecular Similarity Index
Authors: Reynolds Christopher A. , Burt Catherine , Graham Richards W. 
Published: October 2006

AbstractMolecular similarity is a tool for rationalising the biological activities of potential drug molecules. The most useful form of molecular similarity calculations are usually based upon the molecular electrostatic potential and generally use formulae due to Carbo or Hodgkin but these formulae do not give a similarity index which varies linearly with molecular electrostatic potential. Consequently, a new linear index has been proposed and the potential advantages of this index are discussed.
3D‐Quantitative Structure‐Activity Relationships: Description of Electronic Effects Directly from 3D Structures Using a GRID‐Comparative Molecular Field Analysis (CoMFA) Approach
Authors: Kim Ki Hwan 
Published: October 2006

AbstractThe applicability of the comparative molecular field analysis (CoMFA) method to describe the electronic effects in 3D quantitative structure‐activity relationships (QSAR) has been investigated. Molecular fields calculated using an H + probe with the GRID force fields produced significant correlations with excellent cross‐validations. The CoMFA correlations were compared with the correlations of Hammett σ, σ+ or σ– in the traditional biological QSAR. The results indicate that the CoMFA treatment of electronic effects using an H+ probe as in this study are adequate for describing the corresponding effects in 3D QSAR studies.
Using Theoretical Descriptors in Quantitative Structure‐Activity Relationships: Opiate Receptor Activity by Fentanyl‐like Compounds
Authors: Famini George R. , Ashman William P. , Mickiewicz Alexander P. , Wilson Leland Y. 
Published: October 2006

AbstractThe number of applications of computational techniques to medicinal chemistry is growing rapidly. Quantitative Structure‐Activity Relationships (QSAR) have been used very successfully to correlate structural features to biological activities. A type of QSAR, Linear Solvation Energy Relationships (LSER) has been used to correlate a large number and wide variety of biological properties. Famini and Wilson have developed a theoretical extension of the LSER, called the TLSER, that incorporates only computationally derived descriptors. We have applied the TLSER methodology to a series of fentanyl‐like compounds that exhibit activity at the opiate receptor. TLSER correlations of the entire data set, as well as specific subsets are considered.