bluuebunny/crossref_metadata_2025_split huggingface dataset:
Functional residual capacity and passive compliance measurements after antenatal steroid therapy in preterm infants
Authors: McEvoy Cindy , Bowling Susan , Williamson Kathleen , Stewart Marion , Durand Manuel 
Published: August 2002

AbstractStudies in preterm animal models have shown that antenatal corticosteroids enhance lung maturation by improving a variety of physiologic variables, including lung volumes. Changes in lung volume of preterm infants treated with a full course of antenatal steroids have not been investigated. We hypothesized that a full course of antenatal steroids would significantly increase functional residual capacity (FRC) in treated vs. untreated preterm infants. The objective of our study was to compare FRC and respiratory mechanics in steroid treated vs. untreated preterm infants. FRC and passive respiratory mechanics were prospectively studied within 36 hr of life in 20 infants (25–34 weeks of gestation) who had received a full course of antenatal steroids and in 20 matched untreated preterm infants. FRC was measured with the nitrogen washout method, and respiratory mechanics with the single‐breath occlusion technique.Preterm infants who received steroids (n = 20; mean birth weight = 1,230 g; gestational age = 28.8 weeks) had a significantly higher FRC (29.5 vs. 19.3 mL/kg; P < 0.001) than untreated infants (n = 20; birth weight = 1,202 g; gestational age = 28.5 weeks). Passive respiratory system compliance was also increased in treated vs. untreated infants (P < 0.05).In conclusion, FRC and passive respiratory system compliance were significantly improved in preterm infants (25–34 weeks gestation) treated with a full course of antenatal steroids, compared to matched untreated infants. Although this study was not randomized, it confirms that antenatal steroids have important effects on pulmonary function that may contribute to a decreased risk of respiratory distress syndrome in treated preterm infants. Pediatr Pulmonol. 2001; 31:425–430. © 2001 Wiley‐Liss, Inc.
Sex differences in response to steroids in preterm sheep lungs are not explained by glucocorticoid receptor number or binding affinity*
Authors: Kovar Jana , Waddell Brendan J. , Sly Peter D. , Willet Karen E. 
Published: August 2002

AbstractWe recently reported that prenatal glucocorticoid therapy is less effective at promoting an improvement in lung function in male than in female sheep. This observation, and the higher incidence of respiratory distress syndrome in human males, suggests that the male fetal lung may be less responsive to glucocorticoids than is the female fetal lung. Since glucocorticoids are known to exert their effects via specific cytoplasmic glucocorticoid receptors (GR), we hypothesized that there may be sexual dimorphism in either the number or binding affinity of lung GR. To test the hypothesis, binding of dexamethasone (a synthetic glucocorticoid, 0.5–40 nM) by cytosolic fractions of male (n = 16) and female (n = 16) fetal sheep lung was measured at 125 days gestation (term = 148 days).Scatchard analysis of dexamethasone binding showed that the total number of GR (Bmax) did not significantly differ between male (346 ± 42 fmol/mg protein) and female (277 ± 23 fmol/mg protein) fetuses. The measured binding affinity (Kd) in male fetal lungs (6.85 ± 0.43 nM) was not significantly different from that in females (8.46 ± 1.02 nM).In conclusion, this study suggests that sex differences in fetal sheep lung responses to glucocorticoid therapy are not due to differences in the number or binding affinity of lung GR. Pediatr Pulmonol. 2001; 32:8–13. © 2001 Wiley‐Liss, Inc.
Singular value decomposition analysis of protein sequence alignment score data
Authors: Fogolari F. , Tessari S. , Molinari H. 
Published: August 2002

AbstractOne of the standard tools for the analysis of data arranged in matrix form is singular value decomposition (SVD). Few applications to genomic data have been reported to date mainly for the analysis of gene expression microarray data. We review SVD properties, examine mathematical terms and assumptions implicit in the SVD formalism, and show that SVD can be applied to the analysis of matrices representing pairwise alignment scores between large sets of protein sequences. In particular, we illustrate SVD capabilities for data dimension reduction and for clustering protein sequences. A comparison is performed between SVD‐generated clusters of proteins and annotation reported in the SWISS‐PROT Database for a set of protein sequences forming the calycin superfamily, entailing all entries corresponding to the lipocalin, cytosolic fatty acid‐binding protein, and avidin–streptavidin Prosite patterns. Proteins 2002;46:161–170. © 2001 Wiley‐Liss, Inc.
Pressure effect on denaturant‐induced unfolding of hen egg white lysozyme
Authors: Sasahara Kenji , Sakurai Masao , Nitta Katsutoshi 
Published: August 2002

AbstractThe influence of hydrostatic pressure (≤100 MPa) on denaturant‐induced unfolding of hen egg white lysozyme was investigated by means of ultraviolet spectroscopy at various temperatures. Assuming a two‐state transition model, the dependence of Gibbs free‐energy change of unfolding on the denaturant concentration was calculated. Under applied hydrostatic pressure, these data were interpreted as suggesting that a two‐state model is not applicable in a restricted temperature range; the dominant effect of hydrostatic pressure is to affect the cooperativity in protein unfolding due to a chemical equilibrium shift in the direction of the reduction in the system volume. The deviation from the two‐state transition model appears to be rationalized by assuming that applied pressure induces an intermediate conformation between the native and unfolded states of the protein. The implication of the thermodynamic stability of protein under pressure was discussed. Proteins 2001;44:180–187. © 2001 Wiley‐Liss, Inc.
The crystal structure of chorismate lyase shows a new fold and a tightly retained product
Authors: Gallagher D. Travis , Mayhew Martin , Holden Marcia J. , Howard Andrew , Kim Kyung‐Jin , Vilker Vincent L. 
Published: August 2002

AbstractThe enzyme chorismate lyase (CL) catalyzes the removal of pyruvate from chorismate to produce 4‐hydroxy benzoate (4HB) for the ubiquinone pathway. In Escherichia coli, CL is monomeric, with 164 residues. We have determined the structure of the CL product complex by crystallographic heavy‐atom methods and report the structure at 1.4‐Å resolution for a fully active double Cys‐to‐Ser mutant and at 2.0‐Å resolution for the wild‐type. The fold involves a 6‐stranded antiparallel β‐sheet with no spanning helices and novel connectivity. The product is bound internally, adjacent to the sheet, with its polar groups coordinated by two main‐chain amides and by the buried side‐chains of Arg 76 and Glu 155. The 4HB is completely sequestered from solvent in a largely hydrophobic environment behind two helix–turn–helix loops. The extensive product binding that is observed is consistent with biochemical measurements of slow product release and 10‐fold stronger binding of product than substrate. Substrate binding and kinetically rate‐limiting product release apparently require the rearrangement of these active‐site‐covering loops. Implications for the biological function of the high product binding are considered in light of the unique cellular role of 4HB, which is produced by cytoplasmic CL but is used by the membrane‐bound enzyme 4HB octaprenyltransferase. Proteins 2001;44:304–311. © 2001 Wiley‐Liss, Inc.
Insecticidal properties of essential plant oils against the mosquito Culex pipiens molestus (Diptera: Culicidae)
Authors: Traboulsi Abdallah F , Taoubi K , El‐Haj Samih , Bessiere J M , Rammal Salma 
Published: August 2002

AbstractThe insecticidal activities of essential oil extracts from leaves and flowers of aromatic plants against fourth‐instar larvae of the mosquito Culex pipiens molestus Forskal were determined. Extracts of Myrtus communis L were found to be the most toxic, followed by those of Origanum syriacum L, Mentha microcorphylla Koch, Pistacia lentiscus L and Lavandula stoechas L with LC50 values of 16, 36, 39, 70 and 89 mg litre−1, respectively. Over 20 major components were identified in extracts from each plant species. Eight pure components (1,8‐cineole, menthone, linalool, terpineol, carvacrol, thymol, (1S)‐(−)‐α‐pinene and (1R)‐(+)‐α‐pinene) were tested against the larvae. Thymol, carvacrol, (1R)‐(+)‐α‐pinene and (1S)‐(−)‐α‐pinene were the most toxic (LC50 = 36–49 mg litre−1), while menthone, 1,8‐cineole, linalool and terpineol (LC50 = 156–194 mg litre−1) were less toxic.© 2002 Society of Chemical Industry
Pesticide soil sorption parameters: theory, measurement, uses, limitations and reliability
Authors: Wauchope R Don , Yeh Simon , Linders Jan B H J , Kloskowski Regina , Tanaka Keiji , Rubin Baruch , Katayama Arata , Kördel Werner , Gerstl Zev , Lane Michael , Unsworth John B 
Published: August 2002

AbstractThe soil sorption coefficient Kd and the soil organic carbon sorption coefficient KOC of pesticides are basic parameters used by environmental scientists and regulatory agencies worldwide in describing the environmental fate and behavior of pesticides. They are a measure of the strength of sorption of pesticides to soils and other geosorbent surfaces at the water/solid interface, and are thus directly related to both environmental mobility and persistence. KOC is regarded as a ‘universal’ parameter related to the hydrophobicity of the pesticide molecule, which applies to a given pesticide in all soils. This assumption is known to be inexact, but it is used in this way in modeling and estimating risk for pesticide leaching and runoff. In this report we examine the theory, uses, measurement or estimation, limitations and reliability of these parameters and provide some ‘rules of thumb’ for the use of these parameters in describing the behavior and fate of pesticides in the environment, especially in analysis by modeling.© 2002 Society of Chemical Industry
A review of plant species used to treat conjunctivitis
Authors: Sharma Poonam , Singh Gian 
Published: August 2002

AbstractConjunctivitis is a major occular external infection in tropical countries. Although not a very serious disease, it gives much discomfort and sometimes leads to partial blindness or blindness due to corneal involvement. Conjunctivitis has been known to occur in epidemic proportions in different parts of the world, mainly African and Asian regions. The indigenous cure of conjunctivitis using herbal products has been popular for centuries. This paper is an attempt to compile information on plants mentioned as a cure for conjunctivitis during ethnobotanical surveys between 1933 and 2000. Plants mentioned as a cure in various systems of medicine, namely Siddha and Ayurveda, are also included. Copyright © 2002 John Wiley & Sons, Ltd.
Impact of certain flavonoids on lipid profiles—­potential action of Garcinia cambogia flavonoids
Authors: Koshy Asha Sarah , Vijayalakshmi N. R. 
Published: August 2002

AbstractFlavonoids from Cocos nucifera, Myristica fragrance, Saraka asoka and Garcinia cambogia exerted hypolipidaemic activity in rats. Lipid lowering activity was maximum in rats administered flavonoids (10 mg/kg BW/day) from Garcinia cambogia. A dose response study revealed biphasic activity. Higher doses were less effective in reducing lipid levels in serum and tissues, although devoid of toxic effects. Copyright © 2001 John Wiley & Sons, Ltd.
The protective effect of HD‐03 in CCl4‐induced hepatic encephalopathy in rats
Authors: Mitra S. K. , Venkataranganna M. V. , Gopumadhavan S. , Anturlikar S. D. , Seshadri S. J. , Venkatesha Udupa U. 
Published: August 2002

AbstractThe liver is a major parenchymal organ involved in many functional activities in the body. Hepatic encephalopathy is a syndrome characterized by increased blood ammonia level and is one of the major complications of cirrhosis. In the present study the protective effect of HD‐03, a poly‐herbal formulation, was evaluated against CCl4‐induced hepatic encephalopathy in rats. Hepatic encephalopathy was induced in Wistar rats by administration of CCl4 at a dose of 1 mL/kg orally in liquid paraffin (1:1) twice a week for 90 days. The liver enzymes (SGPT and SGOT) and blood ammonia levels were significantly (p < 0.001) higher in the CCl4‐intoxicated group compared with the untreated control group. Administration of HD‐03 at a dose of 750 mg/kg orally as an aqueous suspension significantly prevented the elevation of SGPT, SGOT and blood ammonia levels. Histomorphometric evaluation of liver and brain showed a protective effect of the HD‐03 treatment, thus correlating with the changes in biochemical profiles. The protective effect of HD‐03 against CCl4‐induced encephalopathy may be due to the improved hepatocellular function, which in turn helps in regulating the metabolism of ammonia. However, further studies are required to measure the activity of enzymes involved in the urea cycle and brain aromatic amino acids in order to elucidate the exact mechanism of action of HD‐03. Copyright © 2001 John Wiley & Sons, Ltd.
Antioxidant activity of extracts from plants growing in Sardinia
Authors: Dessí M. Assunta , Deiana Monica , Rosa Antonella , Piredda Martina , Cottiglia Filippo , Bonsignore Leonardo , Deidda Delia , Pompei Raffaello , Corongiu Francesco P. 
Published: August 2002

AbstractThe present work was carried out to study the effect of some plant methanol extracts and essential oils on lipid peroxidation in simple in vitro systems. The tested extracts were obtained from four plants, commonly known in the Mediterranean area, indigenous to Sardinia: Artemisia arborescens L., Calycotome villosa L., Daphne gnidium L. or naturalized in the island, Eucalyptus globulus Labill. The activity of the extracts was investigated during both autoxidation and iron or EDTA‐mediated oxidation of linoleic acid at 37 °C in the absence of solvent, and compared with that of BHT, α‐tocopherol and EDTA. During linoleic acid autoxidation all the extracts were active, showing an antioxidant activity in the order: BHT >α‐ tocopherol >Daphne gnidium (methanol extract) >Eucalyptus globulus (essential oil) >Calycotome villosa (essential oil) >Artemisia arborescens (essential oil and methanol extract) >Calycotome villosa (methanol extract). None showed any prooxidant activity. During the iron‐catalysed oxidation of linoleic acid the oils were not active, while all the methanol extracts showed some efficiency in preventing the oxidation process. All the extracts were also tested on cell cultures to investigate their cytotoxic activity or their ability to inhibit the growth of some pathogenic microorganisms. Copyright © 2001 John Wiley & Sons, Ltd.
Effect of the antiulcer polysaccharide fraction from Bupleurum falcatum L. on the healing of gastric ulcer induced by acetic acid in rats
Authors: Matsumoto T. , Sun X. B. , Hanawa T. , Kodaira H. , Ishii K. , Yamada H. 
Published: August 2002

AbstractAn antiulcer polysaccharide fraction (BR‐2) from Bupleurum falcatum L. was examined for its effect on the healing of chronic ulcers induced by acetic acid in rats. When BR‐2 was administered orally to the rats, it was shown to be effective in the healing of acetic acid‐induced chronic ulcer. This result suggests that the use of herbal prescriptions containing B. falcatum L. may prove useful for the treatment of peptic ulcers. Copyright © 2002 John Wiley & Sons, Ltd.
Low‐cost response surface methods from simulation optimization
Authors: Allen Theodore T. , Yu Liyang 
Published: August 2002

AbstractWe propose ‘low‐cost response surface methods’ (LCRSMs) that typically require half the experimental runs of standard response surface methods based on central composite and Box Behnken designs, but yield comparable or lower modeling errors under realistic assumptions. In addition, the LCRSMs have substantially lower modeling errors and greater expected savings compared with alternatives with comparable numbers of runs, including small composite designs and computer‐generated designs based on popular criteria such as D‐optimality. The LCRSM procedures appear to be the first experimental design methods derived as the solution to a simulation optimization problem. Together with modern computers, simulation optimization offers unprecedented opportunities for applying clear, realistic multicriterion objectives and assumptions to produce useful experimental design methods. We compare the proposed LCRSMs with alternatives based on six criteria. We conclude that the proposed methods offer attractive alternatives when the experimenter is considering dropping factors to use standard response surface methods or would like to perform relatively few runs and stop with a second‐order model. Copyright © 2002 John Wiley & Sons, Ltd.
Cassette‐accelerated rapid rat screen: a systematic procedure for the dosing and liquid chromatography/atmospheric pressure ionization tandem mass spectrometric analysis of new chemical entities as part of new drug discovery
Authors: Korfmacher Walter A. , Cox Kathleen A. , Ng Kwokei J. , Veals John , Hsieh Yunsheng , Wainhaus Sam , Broske Lisa , Prelusky Dan , Nomeir Amin , White Ronald E. 
Published: August 2002

AbstractThis report addresses the continuing need for increased throughput in the evaluation of new chemical entities (NCEs) in terms of their pharmacokinetic (PK) parameters by describing an alternative procedure for increasing the throughput of the in vivo screening of NCEs in the oral rat PK model. The new approach is called ‘cassette‐accelerated rapid rat screen’ (CARRS). In this assay, NCEs are dosed individually (n = 2 rats/compound) in batches of six compounds per set. The assay makes use of a semi‐automated protein precipitation procedure for sample preparation in a 96‐well plate format. The liquid chromatography/atmospheric pressure ionization tandem mass spectrometry (LC/API‐MS/MS) assay is also streamlined by analyzing the samples as ‘cassettes of six’. Using this new approach, a threefold increase in throughput was achieved over the previously reported ‘rapid rat screen’. Copyright © 2001 John Wiley & Sons, Ltd.
Monitoring the production yields of vincristine and vinblastine in Catharanthus roseus from somatic embryogenesis. Semiquantitative determination by flow‐injection electrospray ionization mass spectrometry
Authors: Favretto Donata , Piovan Anna , Filippini Raffaella , Caniato Rosamaria 
Published: August 2002

AbstractA semiquantitative determination of two bis‐indole antitumor alkaloids, vincristine and vinblastine, has been performed by flow‐injection electrospray ionization mass spectrometric analysis of the extracts of Catharanthus roseus. Leaves and flowers of two different phenotypes (pink flower and white flower) obtained from somatic embryogenesis were thus examined and compared with the field‐grown mother plant. Different amounts of vincristine and vinblastine were detected depending on the examined samples. Copyright © 2001 John Wiley & Sons, Ltd.
A highly automated 96‐well solid phase extraction and liquid chromatography/tandem mass spectrometry method for the determination of fentanyl in human plasma
Authors: Shou Wilson Z. , Jiang Xiangyu , Beato Brian D. , Naidong Weng 
Published: August 2002

AbstractA high‐throughput bioanalytical method based on automated sample transfer, automated solid phase extraction, and fast liquid chromatography/tandem mass spectrometry (LC/MS/MS) analysis, has been developed for the determination of the analgesic fentanyl in human plasma. Samples were transferred into 96‐well plates using an automated sample handling system. Automated solid phase extraction (SPE) was carried out using a 96‐channel programmable liquid‐handling workstation using a mixed‐mode sorbent. The extracted samples were then dried down, reconstituted and injected onto a silica column using an aqueous/organic mobile phase with tandem mass spectrometric detection. The method has been validated over the concentration range 0.05–100 ng/mL fentanyl in human plasma, based on a 0.25‐mL sample size. The assay is sensitive, specific and robust. More than 2000 samples have been analyzed using this method. The automation of the sample preparation steps not only increased the analysis throughput, but also facilitated the transfer of the method between different bioanalytical laboratories of the same organization. Copyright© 2001 John Wiley & Sons, Ltd.
Qualitative and quantitative determination of poloxamer surfactants by mass spectrometry
Authors: Takáts Z. , Vékey K. , Hegedüs L. 
Published: August 2002

AbstractPoloxamers are polyethylene‐polypropylene glycol linear co‐polymers. A simple matrix‐assisted laser desorption/ionization mass spectrometry (MALDI‐MS) method has been developed for the determination of the average molecular weight of poloxamers. The molecular mass of five standard poloxamers determined by MALDI closely corresponds to that specified by the manufacturers, and no mass distribution effects were observed. Quantitation of distributions based on the molecular mass envelope using electrospray (ES) ionization was unsuccessful. To overcome this problem, quantitation was based on fragment ions (m/z 45 and 59) which gave reproducible signals using a very high orifice voltage (∼200 eV). Poloxamer concentrations were determined accurately with a good linear response using the standard addition method. We believe that the use of very small fragment ions for quantitation of polymers may become a widely applicable general technique. Copyright © 2001 John Wiley & Sons, Ltd.
Determination of gatifloxacin in human plasma by liquid chromatography/electrospray tandem mass spectrometry
Authors: Vishwanathan Karthick , Bartlett Michael G. , Stewart James T. 
Published: August 2002

AbstractGatifloxacin is an advanced‐generation, 8‐methoxyfluoroquinolone that is active against a broad spectrum of pathogens, including antiobiotic resistant Streptococcus pneumoniae. Development of a rapid, sensitive and selective method for the determination of gatifloxacin in human plasma is essential for understanding the pharmacokinetics of the drug when administered orally or intravenously. Solid phase extraction (SPE) using Oasis® HLB was used to extract gatifloxacin and the internal standard ciprofloxacin from plasma. A method based on liquid chromatography/electrospray tandem mass spectrometry (LC/ESI‐MS/MS) was developed and validated to quantitate gatifloxacin in human plasma. The precursor and major product ions of the analyte were monitored on a triple quadrupole mass spectrometer with positive ion electrospray ionization (ESI) in the multiple reaction monitoring (MRM) mode. Mechanisms for the formation of collision‐induced dissociation products of gatifloxacin are proposed. Linear calibration curves were generated from 10–1000 ng/mL with coefficients of determination greater than 0.99. The interday and intraday precision (%RSD) was less than 6.0% and accuracy (%error) was less than 5.4% for gatifloxacin. The limit of detection (LOD) for the method was 500 pg/mL based on a signal‐to‐noise ratio of 3. Copyright © 2001 John Wiley & Sons, Ltd.