bluuebunny/crossref_metadata_2025_split huggingface dataset:
Mass spectrometric analysis of combinatorial peptide libraries derived from the tandem repeat unit of MUC2 mucin
Authors: Schlosser Gitta , Takáts Zoltán , Vékey Károly , Pócsfalvi Gabriella , Malorni Antonio , Windberg Emöke , Kiss Andrea , Hudecz Ferenc 
Published: June 2003

AbstractFour 19‐member synthetic peptide libraries, based on the TX1TX2T epitope motif of the mucin‐2 gastrointestinal glycoprotein (MUC2) and ranging in peptide length from dipeptides to 15‐mers (XT, TXT, TQTXT and KVTPTPTPTGTQTXT), were synthesized by combinatorial solid phase peptide synthesis using the portioning‐mixing combinatorial approach, and analysed by electrospray ionization mass spectrometry at different (1000–10 000) resolutions. Most of the components of the individual libraries could be easily identified in a single‐stage molecular mass screening experiment. The resolving power of the instrument becomes an important factor above 800–1000 Da molecular mass, when predominantly multiply charged molecular ions are formed. Approaches to the identification of isobars (glutamine/lysine), isomers (leucine/isoleucine) and sequence variations by tandem mass spectrometry, and/or by high‐performance liquid chromatography‐mass spectrometry are outlined. Copyright © 2003 European Peptide Society and John Wiley & Sons, Ltd.
Nascent helix in the multiphosphorylated peptide αS2‐casein(2–20)
Authors: Huq N. Laila , Cross Keith J. , Reynolds Eric C. 
Published: June 2003

AbstractSequence‐specific nuclear magnetic resonance (NMR) assignments have been determined for the peptide αS2‐CN(2–20) containing the multiphosphorylated motif‐8Ser(P)‐Ser(P)‐Ser(P)‐Glu‐Glu12‐ in the presence of molar excess Ca2+. The secondary structure of the peptide was characterized by sequential (i,i + 1), medium‐range (i,i + 2/3/4) nOes and Hα chemical shifts. Molecular modelling of the peptide based on these constraints suggests a nascent helix for residues Ser(P)9 to Glu12. The spectral data for αS2‐CN(2–20) were compared with those of other casein phosphopeptides β‐CN(1–25) and αS1‐CN(59–79) that also contain the multiphosphorylated motif. This comparison revealed a similar pattern of secondary amide chemical shifts in the multiphosphorylated motif. However, the patterns of medium‐range nOe connectivities in the three peptides suggests they have distinctly different conformations in the presence of Ca2+ despite having a high degree of sequential similarity. Copyright © 2003 European Peptide Society and John Wiley & Sons, Ltd.
The number needed to treat: a useful clinical measure or a case of the Emperor's new clothes?
Authors: Grieve Andrew P. 
Published: June 2003

AbstractThe number needed to treat (NNT) was introduced into the medical literature as an easily understood and useful measure of treatment effect for clinical trials in which the main outcome variable is binary. It has been argued that it is more easily understood by practising physicians than more statistically based measures. In this paper we review the claims made for the NNT and question whether it is truly understandable to physicians, and look at issues around determining a confidence interval, or a Bayesian interval, for the NNT. Copyright © 2003 John Wiley & Sons, Ltd.
Negative binomial control limits for count data with extra‐Poisson variation
Authors: Hoffman David 
Published: June 2003

AbstractTraditional techniques for calculating control limits for processes with discrete responses are based on the Poisson distribution. However, for many processes, the assumption of a Poisson distribution is violated. In such cases, use of traditional Poisson control limits may result in an inflated risk of Type I error. The negative binomial distribution is a natural extension of the Poisson distribution and allows for over‐dispersion relative to the Poisson distribution. A simple approach to calculating exact and approximate control limits for count data based on the negative binomial distribution is described. The approach is illustrated by application to water bacteria count data taken from a water purification system. Copyright © 2003 John Wiley & Sons, Ltd.
Antibacterial activity of medicinal plant extracts against periodontopathic bacteria
Authors: Iauk L. , Lo Bue A. M. , Milazzo I. , Rapisarda A. , Blandino G. 
Published: June 2003

AbstractThis study was performed to evaluate the antibacterial activity of Althaea ofﬁcinalis L. roots, Arnica montana L. ﬂowers, Calendula ofﬁcinalis L. ﬂowers, Hamamelis virginiana L. leaves, Illicium verum Hook. fruits and Melissa ofﬁcinalis L. leaves, against anaerobic and facultative aerobic periodontal bacteria: Porphyromonas gingivalis, Prevotella spp., Fusobacterium nucleatum, Capnocytophaga gingivalis, Veilonella parvula, Eikenella corrodens, Peptostreptococcus micros and Actinomyces odontolyticus. The methanol extracts of H. virginiana and A. montana and, to a lesser extent, A. ofﬁcinalis were shown to possess an inhibiting activity (MIC ≤ 2048 mg/L) against many of the species tested. In comparison, M. ofﬁcinalis and C. ofﬁcinalis extracts had a lower inhibiting activity (MIC ≥ 2048 mg/L) against all the tested species with the exception of Prevotella sp. Illicium verum methanol extract was not very active though it had a particular good activity against E. corrodens. The results suggest the use of the alcohol extracts of H. virginiana, A. montana and A. ofﬁcinalis for topical medications in periodontal prophylactics. Copyright © 2003 John Wiley & Sons, Ltd.
Effect of Coccinia indica leaf extract on plasma antioxidants in streptozotocin‐ induced experimental diabetes in rats
Authors: Venkateswaran S. , Pari L. 
Published: June 2003

AbstractThe present study was carried out to investigate the antioxidant effect of an ethanolic extract of Coccinia indica leaves, an indigenous plant used in Ayurvedic Medicine in India, in Streptozotocin‐diabetic rats. Oral administration of Coccinia indica leaf extract (CLEt) (200 mg/kg body weight) for 45 days resulted in a signiﬁcant reduction in plasma thiobarbituric acid reactive substances, hydroperoxides, vitamin E and ceruloplasmin. The extract also caused a signiﬁcant increase in plasma vitamin C and reduced glutathione, which clearly shows the antioxidant property of CLEt. The effect of CLEt at 200 mg/kg body weight was more effective than glibenclamide. Copyright © 2003 John Wiley & Sons, Ltd.
The cytotoxicity of methyl protoneogracillin (NSC‐698793) and gracillin (NSC‐698787), two steroidal saponins from the rhizomes of Dioscorea collettii var. hypoglauca, against human cancer cells in vitro
Authors: Hu Ke , Yao Xinsheng 
Published: June 2003

AbstractIn our continuous studies of anticancer activity of steroidal saponins from the rhizomes of Dioscorea collettii var. hypoglauca (Dioscoreaceae), methyl protoneogracillin (NSC‐698793) and gracillin (NSC‐698787) were tested for cytotoxicity against human cancer cell lines from leukemia and eight solid tumor diseases. As a result, methyl protoneogracillin was cytotoxic against all the test cell lines with GI50 < 100 µM, especially selectively against two leukemia lines (CCRF‐CEM and RPMT‐8226), one colon cancer line (KM12), two central nervous system (CNS) cancer lines (SF‐539 and U251), one melanoma line (M14), one renal cancer line (786‐0), one prostate cancer line (DU‐145), and one breast cancer line (MDA‐MB‐435), with GI50 ≤ 2.0 µM. Leukemia, CNS cancer, and prostate cancer were the most sensitive subpanels, while ovarian cancer was the least sensitive subpanels. The preliminary toxicity studies showed that the maximum tolerant dose was 600 mg/kg for methyl protoneogracillin to mice. Gracillin was cytotoxic against most cell lines with GI50, TGI and LC50 at micromolar levels, but no activity against EKVX (non‐small cell lung cancer), HT29 (colon cancer), OVCAR‐5 (ovarian cancer), and SN12C (renal cancer). Based on structure‐activity relationship, C‐25 R/S conﬁguration was critical for leukemia selectivity between methyl protoneogracillin and methyl protogracillin. F‐ring was critical to selectivity between furostanol (methyl protoneogracillin and methyl protogracillin) and spirostanol (gracillin) saponins in this study. By an analysis of COMPARE software, no compounds in the NCI's database had similar mean graphs to those of methyl protoneogracillin and gracillin, respectively, indicating potential novel mechanism(s) of action involved. Put all in together, methyl protoneogracillin has been selected as a potential anticancer candidate for hollow ﬁber assay to nude mice, but gracillin will not be pursued due to lack of selectivity against human cancer diseases. Copyright © 2003 John Wiley & Sons, Ltd.
Effects of soybean ethanol extract on the cell survival and oxidative stress in osteoblastic cells
Authors: Choi Eun Mi , Koo Sung Ja 
Published: June 2003

AbstractRecent evidence suggests that high concentrations of tumor necrosis factor‐α (TNF‐α) and nitric oxide (NO) are thought to increase the apoptosis in osteoblasts and bone resorption and may have important roles in the regulation of osteoblast and osteoclast metabolism, especially in rheumatoid arthritis. The present study was performed to investigate the effect of soybean ethanol extract on the scavenging properties using DPPH and the TNF‐α and NO production of osteoblastic MC3T3‐E1 cells. The soy extract and its fractions according to polarity displayed a strong free radical scavenger activity at 0.01∼0.1g/L, except for aquous fraction which had no signiﬁcant effect on the function of MC3T3‐E1 cells (p < 0.05). TNF‐α secretion by MC3T3‐E1 cells was reduced signiﬁcantly when stimulated with soy extract (0.05 g/L). Nitrite accumulation in culture medium and apoptosis of MC3T3‐E1 cells were induced by the addition of 10−10 M TNF‐α, and inhibited by the simultaneous addition of soy extract (0.05g/L). Copyright © 2003 John Wiley & Sons, Ltd.
Relaxant effect of essential oil and hydro‐alcoholic extract of Pycnocycla spinosa Decne. exBoiss. on ileum contractions
Authors: Sadraei H. , Asghari G. , Naddafi A. 
Published: June 2003

AbstractPycnocycla spinosa is an essential oil from a wild plant growing in central Iran. However, so far its pharmacological effects have not been studied. The aim of this study was to look for relaxant effects of the essential oil and hydro‐alcoholic extract of P. spinosa on rat isolated ileum contractions induced by KCl and acetylcholine (ACh). P. spinosa essential oil (PSEO) and the hydro‐alcoholic extract inhibited the response to 80 mM KCl in a concentration‐dependent manner and attenuated the maximum attainable response of ACh concentration‐response curve. Furthermore, in caster oil induced diarrhoea, the hydro‐alcoholic extract had a dose‐dependent anti‐diarrhoeal effect. This study showed that P. spinosa essential oil and its hydro‐alcoholic extract act as a relaxant of rat isolated ileum. As the inhibition of contractile over‐activity of the ileum is the basis for the treatment of gastro‐intestinal disorders such as diarrhoea, P. spinosa may have clinical beneﬁts for treatment of this condition. Copyright © 2003 John Wiley & Sons, Ltd.
Different responses of three rodent Plasmodia species, Plasmodium yoelii 17XL, P. berghei NK65 and P. chabaudi AS on treatment with febrifugine and isofebrifugine mixture from Hydrangea macrophylla var. Otaksa leaf in ICR mice
Authors: Ishih Akira , Miyase Toshio , Ohori Kaneo , Terada Mamoru 
Published: June 2003

AbstractThe antimalarial activity of Hydrangea macrophylla var. Otaksa alkaloids was evaluated against Plasmodium yoelii 17XL, P. berghei NK65 and P. chabaudi AS in ICR mice. For trials in P. yoelii 17XL or P. chabaudi AS infections, mice were infected intraperitoneally with 105, 106 and 107 parasitized erythrocytes, respectively, and in P. berghei NK65 infections, mice were infected intraperitoneally with 103, 104 and 105 parasitized erythrocytes, respectively. Three days after injection, mice were orally given febrifugine and isofebrifugine mixture at 1 mg/kg in the treated group and 0.5% cremophor EL solution in the untreated, infected one, respectively, twice a day for 5 consecutive days. In P. yoelii 17XL infections, mice in all the non‐treated controls died from 5 to 9 dpi with a gradual body weight loss and increasing parasitemias. In the treated groups, the mouse body weight gradually decreased after the end of administration but turned to increase in several days, and except one mouse in the group given 106 parasitized erythrocytes, other mice survived during the experiment. Mice given orally the mixture showed low parasitemia levels during administration. Following a transient recrudescence of malaria parasites in the bloodstream of treated mice, no parasites could be detected by a microscopic examination. In P. berghei NK65 infections, mice in all the non‐treated controls died from 7 to 12 dpi with a gradual body weight loss and increasing parasitemias. In the treated groups, the body weight gradually decreased from 11 dpi and all mice died from 12 to 30 dpi. During a mixture administration all mice showed slight suppression of multiplication of malaria parasites. After the end of administration, however, malaria parasites increased in the bloodstream of the treated mice and all mice died. In P. chabaudi AS infections, there were two different patterns in the course of infection; lethal infection or recovery in both the non‐treated control and treated groups. In the non‐treated and treated groups, mice showed a gradual body weight loss. But the body weights of survivals in both groups turned to increase in several days. Mice in control and treated groups showed as the same profile in the changes of parasitemia. In the non‐treated controls, after a transient peak parasitemia malaria parasites in the bloodstream of survivals could not be detected by a microscopic examination. During a mixture administration, all mice showed suppression of multiplication of malaria parasites. After the end of medication, some mice died with increasing parasitemia. After a transient recrudescence, however, malaria parasites in the bloodstream of survivals could not be detected by a microscopic examination. Copyright © 2003 John Wiley &Sons, Ltd.
HPLC fingerprinting and estimation of the bioactive components of Clutia richardiana L. as a potential hypoglycemic herbal tea
Authors: Abourashed Ehab A. , Ganzera Markus , Khan Ikhlas A. , Khan Shabana , Mossa Jaber S. , El‐Feraly Farouk S. 
Published: June 2003

AbstractClutia richardiana L. is a traditional medicinal herb with demonstrated hypoglycemic effects. An HPLC method (Luna® C18 column, gradient elution, UV detection at 220 nm) has been utilized to determine the levels of the major diterpenes of C. richardiana in extracts obtained by using three different solvents. Extraction with the organic solvents methanol and acetonitrile was more efficient than aqueous extraction with hot water, but nine markers could be detected equally in all extracts. The aqueous extract was non‐toxic against a number of human cell lines, which is a promising indication for its use as a safe and effective antidiabetic herbal preparation. Copyright © 2003 John Wiley & Sons, Ltd.
Anti‐inflammatory and immunomodulatory activities of polysaccharide from Chlorella stigmatophora and Phaeodactylum tricornutum
Authors: Guzmán S. , Gato A. , Lamela M. , Freire‐Garabal M. , Calleja J. M. 
Published: June 2003

AbstractCrude polysaccharide extracts were obtained from aqueous extracts of the microalgae Chlorella stigmatophora and Phaeodactylum tricornutum. The crude extracts were fractionated by ion‐exchange chromatography on DEAE‐cellulose columns. The molecular weights of the polysaccharides in each fraction were estimated by gel filtration on Sephacryl columns. The crude polysaccharide extracts of both microalgae showed anti‐inflammatory activity in the carrageenan‐induced paw edema test. In assays of effects on the delayed hyper‐sensitivity response, and on phagocytic activity assayed in vivo and in vitro, the C. stigmatophora extract showed immunosuppressant effects, while the P. tricornutum extract showed immunostimulatory effects. Copyright © 2003 John Wiley & Sons, Ltd.
Plants for male fertility regulation
Authors: Kamal Raka , Gupta R. S. , Lohiya N. K. 
Published: June 2003

AbstractThe importance of drugs of plant origin in the pursuit of fertility regulating agents for the male from natural products has long been recognized. This review includes 80 plants with 205 references, up to year 2002. The type of extract, dose, animal model and pharmacological activity of these materials have been reviewed in this paper to add impetus to further research and collaboration to resolve the problem of population explosion. Copyright © 2003 John Wiley & Sons, Ltd.
Pycnogenol® prevents haemolytic injury in G6PD deficient human erythrocytes
Authors: Sharma S. C. , Sharma S. , Gulati O. P. 
Published: June 2003

AbstractGlucose6 phosphate dehydrogenase (G6PD) deficiency is the most common X‐linked disorder of human erythrocytes where cells have inadequate capacity to destroy peroxides and high susceptibility towards haemolytic changes. Pycnogenol® is a proprietary dry extract of the French Maritime pine (Pinus pinaster) bark with high ability to scavenge free radicals. In the present study we have investigated if Pycnogenol® can protect G6PD deficient erythrocytes against haemolytic cell damage. Venous blood samples were obtained from six subject of Mediterranean origin with known G6PD deficiency which was also confirmed with standard techniques. Erythrocyte haemolysis in the presence and absence of Pycnogenol® was induced either with tert‐butylhydroperoxide (t‐BHP) or quinine and the haemoglobin release in the supernatant was determined by recording the optical density at 540 nm in a Shimadzu spectrophotometer. Our results have shown that Pycnogenol® has protective action against a Xenobiotic chemical induced haemolysis in G6PD deficient human erythrocytes. Copyright © 2003 John Wiley & Sons, Ltd.
Antiplasmodial activity of extracts and quassinoids isolated from seedlings of Ailanthus altissima (Simaroubaceae)
Authors: Okunade Adewole L. , Bikoff Rachel E. , Casper Steven J. , Oksman Anna , Goldberg Daniel E. , Lewis Walter H. 
Published: June 2003

AbstractExtracts and isolated compounds from seedlings of Ailanthus altissima, were assessed for antiplasmodial activity in vitro. Two quassinoids, ailanthone and 6α‐tigloyloxychaparrinone, isolated from the active extracts showed activity against both chloroquine‐resistant and chloroquine‐sensitive strains of Plasmodium falciparum in vitro. Only ailanthone demonstrated low toxicity against the Vero cell line (kidney cells from the African green monkey). This is the first report of the isolation and antiplasmodial activity of 6α‐tigloyloxychaparrinone from this species. Copyright © 2003 John Wiley & Sons, Ltd.
Dimension related distance and its application in QSAR/QSPR model error estimation
Authors: Xu Yong‐jin , Gao Hua 
Published: June 2003

AbstractIn this paper, the concept of dimension related distance (DRD) is introduced to measure the position of a test compound in the descriptor space of training set compounds in a QSAR/QSPR model. DRD can be used to perform similarity comparison between one compound and a group of compounds. In a QSAR/QSPR model, we find that prediction error is related to the similarity between a test compound and the model training set compounds. DRD seems able to capture this similarity and make it possible to estimate prediction error range of a test compound from calculated DRD.
Comparison of Principal Analysis and the Tucker3 Model
Authors: Morais Helena , Ramos Cristina , Forgács Esther , Jakab Annamaria , Cserháti Tibor , Oliviera José , Illés Tibor , Illés Zoltán 
Published: June 2003

AbstractA three‐ways array data matrix consisting of the activity data of laccase enzyme has been evaluated by both principal component analyses (PCA) and Tucker3 model. Activity data have been determined in 28 culture media, at 6 sampling times and by four strains of Lentinus edodes. PCA has been carried out three times one of the factors being always the variables and the other two factors being the observations. The dimensionality of the matrices of loadings calculated by PCAs and those of component matrices of Tucker3 model has been reduced to two by the nonlinear mapping technique. It has been found that the dimensionality of component matrices for Tucker3 model can be predicted from the results of PCAs. Linear regression analyses indicated that the distribution of the original data points on the two‐dimensional nonlinear maps considerably depends on the fact that the data have been calculated by PCA or by Tucker3 model.
Substructure versus Whole‐molecule Approaches for Calculating Log P
Authors: Mannhold Raimund , Petrauskas Alanas 
Published: June 2003

AbstractThe validity of log P calculations is checked for the substructure methods CLOGP, KOWWIN, and AB/logP and the whole‐molecule method SciLogP via experimental log P for 174 molecules, comprising 90 simple organics and 84 more complex drugs. Averaged absolute residual sums (AARS) give the following ranking for the entire set: CLOGP>KOWWIN≈AB/logP>SciLogP. Separate analysis of simple organics yields: CLOGP>KOWWIN>AB/logP>SciLogP. For the drugs we find: CLOGP≈KOWWIN≈AB/LogP>SciLogP. In a second step, we compared the validity of the calculation programs focussing on structural factors with a critical impact on log P such as resonance and H‐bonding interactions. AARS values show that CLOGP and KOWWIN scored slightly better than AB/LogP and SciLogP; this agrees with the good performance of CLOGP and KOWWIN when dealing with simple compounds. AB/LogP averaged correction factors obtained from both simple and complex compounds, so it produced a slightly lower accuracy. α‐Effects, representing strong interactions between conjugated π‐electrons within polar functional groups, were identified from compounds lacking “isolating carbons”, which break α‐effects. All compounds in this data set are difficult to deal with for the substructure methods, but should be easy to deal with for the whole‐molecule approach. In practice, however, SciLogP performed worse than the substructure methods. The best performance was shown by CLOGP, followed by KOWWIN and AB/LogP. Taken together, all substructure methods produced better results than the whole‐molecule method. The possible explanation may be that substructure methods automatically account for unknown effects by splitting compounds into fragments and/or conducting class‐specific analyses. Whole‐molecule approaches cannot account for unknown effects, as long as they neglect class‐specific analyses. Among the substructure approaches, our results correlate with the methodology of algorithm development. CLOGP and KOWWIN were developed in a long iterative process, using simple organics for increment derivation and complex drugs for algorithm refinement. AB/LogP was developed in a fast two‐step procedure that did not discriminate between simple and complex compounds. So it produced slightly lower accuracy for simple organics, but not lower accuracy for the complex drugs.