bluuebunny/crossref_metadata_2025 huggingface dataset:
Method for localization of sialic acid on cell surface and cell interior in peripheral blood: A pilot study
Authors: Pönniö Maritta , Soukka Jori , Sillanaukee Pekka , Franck Johan , Seveus Lahja
Published: January 2005

This article presents a method for identification and localization of cell surface and intracellular sialoglycoconjugates of peripheral blood cells. To reveal cell surface conjugates, a sample of peripheral blood was incubated with lectin after centrifugation and rinsing. For intracellular localization in leukocytes, RBCs were lysed and the membranes were permeabilized prior to cytochemical reaction. Fluorescein isothiocyanate conjugated lectins were used for visualization in fluorescence microscope. All lectins bound specifically to the surface of erythrocytes. Confocal microscopy showed surface and intracellular labeling of permeabilized leukocytes. A part of the signal in eosinophils originated from binding of anionic fluorophore to cationic granular proteins. Microsc. Res. Tech. 65:292–294, 2004. © 2005 Wiley‐Liss, Inc.
Bioimaging TOF‐SIMS of tissues by gold ion bombardment of a silver‐coated thin section
Authors: Nygren Håkan , Johansson Bengt R. , Malmberg Per
Published: January 2005

The imaging time‐of‐flight secondary‐ion‐mass‐spectrometry (TOF‐SIMS) method was utilized to address the problem of cholesterol localization in rat tissues. Rat kidneys were fixed, cryoprotected by sucrose, frozen, sectioned by cryoultramicrotomy, and dried at room temperature. The samples were either covered with a thin silver layer or analyzed uncovered in an imaging TOF‐SIMS instrument equipped with an Au‐source. The yield of desorbed secondary ions for some species was up to 600‐fold higher after silver coating of the samples. Reference samples of cholesterol were silver‐coated and analyzed by TOF‐SIMS to define significant peaks, specific for cholesterol. Such peaks were found at m/z = 386 (C27H46O+), m/z = 493 (C27H46O107Ag+), m/z = 495 (C27H46O109Ag+), m/z = 879 (C54H92O2107Ag+), and m/z = 881 (C54H92O2109Ag+). The silver‐cationized cholesterol (493 ≤ m/z ≤ 495) signal was localized by imaging TOF‐SIMS in the kidney sections and showed a high cholesterol content in the kidney glomeruli. A more diffuse distribution of cholesterol was also found over areas representing the cytoplasm or plasma membrane of the epithelial cells in the proximal tubules of rat kidney. Microsc. Res. Tech. 65:282–286, 2004. © 2005 Wiley‐Liss, Inc.
Technique to quantify local clustering of synaptic vesicles using single section data
Authors: Nikonenko Alexander G. , Skibo Galina G.
Published: January 2005

Synaptic vesicles are organelles that specialize in the storage of a neurotransmitter that continuously undergo an exo‐endocytotic cycle. During this cycle vesicles change their positions within a presynaptic terminal and their numbers as well as spatial arrangement can provide insight into a neurotransmitter turnover. This article introduces a technique based on the nearest‐neighbor formalism to quantify the proximity of vesicles to active zones and vesicle clustering in different regions of a terminal. The technique, implemented in a software package, uses the two‐dimensional coordinates of features identified in digitized electron micrographs as an input. It has been validated in the analysis of asymmetric synapses of the rat hippocampal CA1 stratum radiatum affected by transient cerebral ischemia. It was shown that a 15‐minute‐long ischemic episode influenced the spatial arrangement of vesicles that were more distant from active zones and had larger intervesicle spacings with respect to the control. The latter effect was apparently stronger within 200 nm distance of active zones. Microsc. Res. Tech. 65:287–291, 2004. © 2005 Wiley‐Liss, Inc.
Glucose transport by english sparrow (Passer domesticus) skeletal muscle: Have we been chirping up the wrong tree?
Authors: Sweazea Karen L. , Braun Eldon J.
Published: January 2005

Glucose uptake by mammalian skeletal muscle has been extensively covered in the literature, whereas the uptake of glucose by avian skeletal muscle has yet to be examined. As skeletal muscle provides the majority of postprandial glucose uptake in mammals, this study was designed to characterize the glucose transport mechanisms and glycogen content of avian skeletal muscle. In addition, plasma glucose levels were measured. English sparrow extensor digitorum communis (EDC) skeletal muscles were used for this study to quantify in vitro radiolabeled‐glucose uptake. Uptake of labeled glucose was shown to decrease in the presence of increasing unlabeled glucose and was maximal by 60 minutes of incubation. Various agents known to increase glucose transport in mammalian tissues, via the insulin and contraction‐responsive pathways, were used to manipulate and characterize in vitro transport in birds. The typical effectors of the mammalian insulin pathway, insulin (2 ng/ml) and insulin‐like growth factor‐1 (48 ng/ml), did not increase skeletal muscle glucose transport. Likewise, inducers of the mammalian contraction‐responsive pathway had no effect on glucose transport by in vitro avian skeletal muscle (5 mM caffeine, 2 mM AICAR (5'–aminoimidazole–4–carboxamide–1–b–D–ribofuranoside). Interestingly, 200µM phloretin, an agent used to block glucose transport proteins, significantly inhibited its uptake (P<0.001). These results suggest that a glucose transporter is responsible for glucose uptake by avian skeletal muscle, albeit at unexpectedly low levels, considering the high plasma glucose concentrations (265.9±53.5 mg/dl) and low skeletal muscle glycogen content (9.1±4.11 nM glucose/mg) of English sparrows. J. Exp. Zool. 303A:143–153, 2005. © 2005 Wiley‐Liss, Inc.
Function of the hepatic melanogenesis in the Newt, Triturus carnifex
Authors: Frangioni Giuliano , Santoni Mario , Bianchi Stefano , Franchi Marco , Fuzzi Giancarlo , Marcaccini Stefano , Varlani Carlo , Borgioli Gianfranco
Published: January 2005

Like the majority of lower vertebrates, the newt Triturus carnifex holds varying quantities of melanin and hemosiderin in the Kupffer cells of the liver. Following hypoxic treatment, the amount of these two pigments can increase to such an extent that they can occupy nearly a quarter of the surface of histological sections. A group of six specimens, anesthetised with chlorbutol, were subjected to hypoxic treatment by keeping them in a respiratory chamber containing degassed water under vacuum, with only 1.1 ppm of residual oxygen, until they had consumed the oxygen completely (4 hours, at a temperature of 18°C). Using hematological and histochemical techniques and computerised image analysis, it has been shown that hypoxic animals not only increase the extent of the melanic areas of the liver from about 5–7% to almost 24% compared to control groups kept under two different respiratory conditions (6 anesthetised specimens exposed to the air and 6 submerged in normoxic water), they also went through a remarkable hemolytic process to justify a parallel increase in hemosiderin deposits. Melanin was extracted from the liver by keeping fragments of the organ for one hour at 37°C in an oxidising solution (20 mL of benzyl alcohol, 10 mL of acetone, 5 mL of 10% hydrogen peroxide, and 4 drops of concentrated ammonia solution), then quickly rinsing them in 50% acetone and subsequently letting them stand for 6 hours in 10mL of distilled water alkalised to pH 12 with a drop of ammonia solution. The extract was then left to sediment at pH 2.5 and the black precipitate washed and dried under vacuum. Elemental and spectrophotometric analyses revealed a significant presence of purines in the melanic pigment. This phenomenon can be explained by the animals' need under hypoxic crisis to rapidly neutralise purines resulting from lysis of the nucleated red blood cells by introducing them into an inert molecular complex. A partial model of structure is proposed here. Synthesis of the mixed polymer is possible through the well‐known capacity of ferrous iron to activate tyrosinase (the enzyme responsible for melanogenesis) even in the absence of DOPA. J. Exp. Zool. 303A: 123–131, 2005. © 2005 Wiley‐Liss, Inc.
Mixed reproductive strategy in Tubifex tubifex (Oligochaeta, Tubificidae)?
Authors: Baldo Laura , Ferraguti Marco
Published: January 2005

Despite the wide use of the tubificid oligochaete Tubifex tubifex in eco‐toxicological studies, the reproductive strategy adopted by the species, that can reasonably be assumed to be the key to its ecological success, is still not well investigated. This study reports on breeding experiments analysed by allozyme markers (Pgi, Pgm, and Idh), accompanied by a study of the sperm production in the species, with the aim to: (1) clarify the type of uniparental reproduction adopted by the species, (2) test the hypothesis that uniparental reproduction is reversible, (3) investigate the occurrence of biparental reproduction in laboratory cultures. Studies of parent‐offspring comparison at polymorphic allozyme loci showed parthenogenetic reproduction and maintenance of asexuality in the parthenogenetic individuals. A cross‐breeding test performed with couples made up of randomly assorted individuals, whose genotype combinations were suitable for discriminating between sexual and asexual reproduction, failed to show biparental reproduction in laboratory cultures: T. tubifex always reproduced parthenogenetically. Unexpectedly, spermiogenetic analysis indicated that both kinds of sperm produced by the species (eusperm and parasperm) were differentiated in individuals raised either in cohort cultures or in isolation (first, second, and third parthenogenetic generations), with a similar pattern of sperm production correlated to the sexual stage. Interestingly, there was no avoidance of mating in any of the collective cultures analysed. Concomitance between parthenogenetic reproduction and a “normal” male functionality, which is typical of a sexually reproducing species, could be justified by a mixed reproductive strategy or a pseudogamy process occurring in T. tubifex. However, several aspects of the reproductive behaviour of the species deserve further investigation. J. Exp. Zool. 303A:168–177, 2005. © 2005 Wiley‐Liss, Inc.
Organic Crystal Rings Formed in Template Polymer Pores by Evaporation of Solvent
Authors: Yu Xiang , Pan Caiyuan
Published: January 2005

Summary: The fabrication of organic crystals into useful forms might play an important role in future electronics technology. A method for fabricating organic crystal rings has been developed. The self‐assembly of six‐armed poly(methyl methacrylate) with a triphenylene core leads to the formation of pores homogeneously distributed in the polymer film. Because the solubility of this polymer in tetrahydrofuran (THF) is lower than that of 2,3,6,7,10,11‐hexamethacrylate triphenylene (HMTP), the holes initially formed and distributed in the polymer film are filled with a THF solution of HMTP. Crystallization nucleation occurs at the edge of holes and HMPT crystals grow at the contact line to form organic crystal rings.

Schematic illustration of crystal‐ring formation.

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Schematic illustration of crystal‐ring formation.
Immobilization and Activation of a Single‐Site Chromium Catalyst for Ethylene Polymerization using MgCl2/AlRn(OEt)3 − n Supports
Authors: Severn John R. , Kukalyekar Nileshkumar , Rastogi Sanjay , Chadwick John C.
Published: January 2005

Summary: The effective immobilization and activation of a single‐site chromium catalyst for ethylene polymerization has been achieved using MgCl2/AlRn(OEt)3 − n supports, without the use of methylaluminoxane (MAO) or a borate activator. High catalyst activity and a spherical polyethylene‐particle morphology is obtained. Furthermore, the single‐site characteristics of the catalyst are retained, the narrow molecular weight distribution of the polymers obtained are apparent from gel permeation chromatography (GPC) and confirmed by rheological characterization.

Shear frequency dependence of the storage modulus of (♦ and ▴) polyethylene ($\overline M _{\rm w} /\overline M _{\rm n}$ = 1.8–1.9) prepared using an immobilized Cr catalyst, compared to (▪) a reference polymer having $\overline M _{\rm w} /\overline M _{\rm n}$ = 4.1.

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Shear frequency dependence of the storage modulus of (♦ and ▴) polyethylene ($\overline M _{\rm w} /\overline M _{\rm n}$ = 1.8–1.9) prepared using an immobilized Cr catalyst, compared to (▪) a reference polymer having $\overline M _{\rm w} /\overline M _{\rm n}$ = 4.1.
1H NMR, FT‐IR and MS studies and PM5 semiempirical calculations of complexes between the Schiff base of gossypol with 2‐(aminomethyl)‐15‐crown‐5 and Ca2+, Pb2+ and Ba2+ cations
Authors: Przybylski Piotr , Schroeder Grzegorz , Brzezinski Bogumil , Bartl Franz
Published: January 2005

A new Schiff base of gossypol with
2‐(aminomethyl)‐15‐crown‐5 (GSCB) was shown to be capable of complexation with Ca2+, Ba2+ and Pb2+ cations. This process of complex formation was studied by electrospray ionization mass spectrometry, 1H NMR and FT‐IR spectroscopy and by the PM5 semiempirical method. It was found that gossypol Schiff base can form a 1:2 complex with Ca2+, 1:1 or 1:2 complexes with Pb2+ and only a 1:1 complex with Ba2+ cation. In all complexes the Schiff base of gossypol exists as an enamine–enamine tautomer. The cations are coordinated through oxygen atoms from the crown part, lone pairs at the N‐atoms and O‐atoms of the O1H(O1′H) hydroxyl groups. The structures of these complexes were calculated by the PM5 semiempirical method and are discussed. Copyright © 2003 John Wiley & Sons, Ltd.
Control of blue mold (Penicillium expansum) by fludioxonil in apples (cv Empire) under controlled atmosphere and cold storage conditions
Authors: Errampalli Deena , Northover John , Skog Lisa , Brubacher Nichole R , Collucci Cheryl A
Published: January 2005

A reduced risk fungicide, fludioxonil, was tested for its efficacy against blue mold caused by thiabendazole‐resistant and ‐sensitive Penicillium expansum (Link) Thom in apples under three storage conditions. In a co‐treatment, fludioxonil and inoculum were applied together to test the protective activity of the fungicide on wounds that had been aged for 1 or 2 days. The fungicide was also tested for its curative activity in post‐inoculation treatment on apples that had been inoculated for 1 or 2 days. Fludioxonil was very effective as co‐treatment and as post‐inoculation treatment. At a concentration of 300 mg litre−1, fludioxonil gave complete control of post‐harvest blue mold caused by the thiabendazole‐resistant and ‐sensitive P expansum for 105 days in controlled atmosphere (CA) storage at 2 (±1) °C, for 42 days in common cold storage at 4 (±1) °C and also in a shelf‐life study for 6 days at 20 (±1) °C. Comparison on the effect of fludioxonil in CA storage and common cold storage showed that higher concentrations of fungicide were needed in cold storage than in CA storage. Fludioxonil at a concentration of 450 mg litre−1, gave 98 and 92% control of blue mold of apples in the simulated shelf‐life studies after CA and common cold storages, respectively. Fludioxonil has a potential to be incorporated in the fungicide resistance management strategies for control of blue mold in apples stored for 105 days. Copyright © 2005 Society of Chemical Industry
Development of PPO inhibitor‐resistant cultures and crops
Authors: Li Xianggan , Nicholl David
Published: January 2005

Recent progress in the development of protoporphyrinogen oxidase (PPO, Protox)1 inhibitor‐resistant plant cell cultures and crops is reviewed, with emphasis on the molecular and cellular aspects of this topic. PPO herbicide‐resistant maize plants have been reported, along with the isolation of plant PPO genes and the isolation of herbicide‐resistant mutants. At the same time, PPO inhibitor‐resistant rice plants have been developed by expression of the Bacillus subtilis PPO gene via targeting the gene into either chloroplast or cytoplasm. Other attempts to develop PPO herbicide‐resistant plants include conventional tissue culture methods, expression of modified co‐factors of the protoporphyrin IX binding subunit proteins, over‐expression of wild‐type plant PPO gene, and engineering of P‐450 monooxygenases to degrade the PPO inhibitor. Copyright © 2005 Society of Chemical Industry
Properties of the energy spectrum of the Heisenberg molecular magnetN= 8
Authors: Labuz M. , Wal A. , Obermayr W. , Kuzma M.
Published: January 2005

The energy spectra of short rings of spinS= 1/2 particles with a nearest neighbour Heisenberg interaction have features which are common for various numbersNof spins. The example ofN= 8 was considered in detail, for which a complete set of eigenstates and eigenvalues is obtained by the Bethe Ansatz model. The results were compared with the rotational band model usually used for the interpretation of experimental data for antiferromagnetic molecular magnets. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
D charge‐density‐wave versus superconducting phase fluctuations in underdoped high‐Tc superconductors
Authors: Zeyher R. , Greco A.
Published: January 2005

The underdoped region in high‐Tc superconductors is characterized by an increase of the d‐wave gap and a decrease of the superconducting transition temperature Tc with decreasing doping. Two effects may cause such a behavior in the t–J model. On the one hand, superconductivity competes and may also coexist with a d charge‐density‐wave state. We discuss this effect by studying the phase diagram of the t–J model at large N (N is the number of internal degrees of freedom), the gap structure in the coexisting region and the resulting c‐axis tunneling spectra. On the other hand, we give rather general arguments in favor of a strong reduction of the phase stiffness near a Mott transition and calculate the resulting drop in Tc at low dopings due to thermal phase fluctuations. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Interplay of orbitally polarized and magnetically ordered phases in doped transition metal oxides
Authors: Frésard Raymond , Raczkowski Marcin , Oleś Andrzej M.
Published: January 2005

We investigate the magnetic instabilities of the two‐dimensional model of interacting eg electrons for hole doping away from two electrons per site in the mean‐field approximation. In particular, we address the occurrence of orbitally polarized states due to the inequivalent orbitals, and their interplay with ferromagnetic and antiferromagnetic spin order. The role played by the Hund's exchange coupling JH and by the crystal field orbital splitting Ez in stabilizing one of the competing phases is discussed in detail. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Towards a solution of the consistent t‐matrix approximation for the U → ∞ Anderson impurity model
Authors: Keiter Hellmut , Baumgartner Klaus
Published: January 2005

The basic integral equations for the consistent t‐matrix approximation (CTMA) of the infinite U Anderson model are formally solved within the slow variable approximation. The solution is compared with a numerical C++ analysis using self adapting nets. Very good agreement is found. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Quantum criticality and superconductivity in heavy‐electron metals
Authors: Steglich F.
Published: January 2005

Recent work on strongly correlated electron systems realized in heavy‐fermion (HF) metals is reviewed. Particular emphasis is put on different types of antiferromagnetic quantum critical points (QCPs). HF superconductivity seems to be favored only in the presence of a QCP of conventional (spin‐density‐wave) rather than of unconventional nature. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Charge and magnetic order in mixed valence systems
Authors: Lemański R.
Published: January 2005

We analyze charge and magnetically ordered phases in systems described by a generalized Falicov‐Kimball model, with a spin‐dependent interaction term representing the Hund's rule. We study ground state properties of the model rigorously on the infinite 2D square lattice, but within the restricted configurational space, composed of all periodic phases (and their mixtures), for which the number of sites per unit cell is less or equal to 4. In the current work we focus on the mixed valence regime, where the total density of electrons is fixed and equal to 1. For a range of intermediate values of the interaction parameters we detected stable charge and magnetic superstructures of the form of stripes. They display various magnetic arrangements of the localized elctrons, including ferri‐ and antiferromagnetic, despite of the assumption of the ferromagnetic on‐site coupling. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Bound states in the phase diagram of the extended Hubbard model
Authors: Bak M.
Published: January 2005

The paper shows how the known, exact results for the two electron bound states can modify the ground state phase diagram of extended Hubbard model (EHM) for on‐site attraction, intersite repulsion and arbitrary electron density. The main result is suppression of the superconducting state in favor of normal phase for small charge densities. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Scanning tunneling microscopy of monoatomic gold chains on vicinal Si(335) surface: experimental and theoretical study
Authors: Krawiec M. , Kwapiński T. , Jałochowski M.
Published: January 2005

We study electronic and topographic properties of the Si(335) surface, containing Au wires parallel to the steps. We use scanning tunneling microscopy (STM) supplemented by reflection of high energy electron diffraction (RHEED) technique. The STM data show the space and voltage dependent oscillations of the distance between STM tip and the surface which can be explained within one band tight binding Hubbard model. We calculate the STM current using nonequilibrium Keldysh Green function formalism. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Spin precession in spin‐polarized transport through an interacting quantum dot
Authors: Rudziński W. , Barnaś J. , Świrkowicz R. , Wilczyński M.
Published: January 2005

Spin‐polarized transport through an interacting single‐level quantum dot coupled to two ferromagnetic leads with non‐collinear magnetizations is analyzed theoretically by means of the nonequilibrium Green function technique. We show that spin precession on the dot, which arises due to an effective exchange field originating from the interaction between the dot and external electrodes, may lead to negative differential conductance. Our results also prove that the diode‐like behavior in asymmetrical junctions with one electrode being half‐metallic is partially suppressed when magnetic moments of the electrodes become non‐collinear. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Anxiolytic properties of Piper methysticum extract samples and fractions in the chick social–separation–stress procedure
Authors: Feltenstein Matt W. , Lambdin L. Corinne , Ganzera M. , Ranjith H. , Dharmaratne W. , Nanayakkara N. P. Dhammika , Khan Ikhlas A. , Sufka Kenneth J.
Published: January 2005

Piper methysticum extract (Kava kava) possesses anxiolytic properties. However, it is unknown whether these effects are best predicted by total kavalactone content or by one or more of its primary kavalactone constituents. Using the chick social separation‐stress procedure as an anxiolytic bioassay, P. methysticum samples containing 12.8–100.0% total kavalactones (Exp. 1) and fractions containing 1–6 kavalactones of varying concentrations (0.1–67.5%; Exps. 2–3) were screened for activity and compared against a 5.0 mg/kg dose of chlordiazepoxide (CDP; Exp. 3). Eight‐day‐old chicks received IP injections of either vehicle or test compounds 30 min before being placed in the presence of two conspeciﬁcs or in isolation for a 3 min observation period. Dependent measures were ventral recumbency latency (sedation), distress vocalizations, and a measure of stress‐induced analgesia (in Exps. 1 and 2 only). P. methysticum extract samples attenuated distress vocalizations in a concentration‐dependent manner. The P. methysticum fraction that contained the highest concentration of dihydrokavain attenuated distress vocalizations in a manner equivalent to that of CDP. The extract samples and fractions that possessed anxiolytic properties did not possess the sedative properties found in CDP. Collectively, these ﬁndings suggest that dihydrokavain may be necessary and sufﬁcient in mediating the anxiolytic properties of P. methysticum extract. Copyright © 2003 John Wiley & Sons, Ltd.
Protection of jejunal crypts by RH‐3 (a preparation of Hippophae rhamnoides) against lethal whole body gamma irradiation
Authors: Goel H. C. , Salin C. A. , Prakash H.
Published: January 2005

RH‐3, an alcoholic extract of whole berries of Hippopheae rhamnoides, has been demonstrated to provide radioprotective activity in terms of survival of mice against whole body lethal irradiation (10 Gy). It was, therefore, investigated for its mode of action by monitoring crypt survival, cellularity of crypts and villi and the magnitude of apoptosis in the GI tract.

Administration of RH‐3 before irradiation (−30 min) increased the number of surviving crypts in the jejunum by a factor of 2.02 (p < 0.05) and villi cellularity by 2.5 fold (p < 0.05) in comparison to the irradiated control. RH‐3 administration before irradiation also reduced the incidence of apoptotic bodies in the crypts (p < 0.05) in a time dependent manner and increased cellularity in the crypts and villi (84 h post irradiation) as compared to control. Caspase‐3 activity was also signiﬁcantly lower in the mice administered RH‐3 before irradiation as compared to irradiated control.

This study indicates that reduction in the radiation induced loss of cellularity of crypts and villi and also decrease in frequency of apoptosis could have contributed towards protection of mice treated with RH‐3 before irradiation. The cellular and molecular mechanisms of radioprotection by Rh‐3 need to be investigated further in detail. Copyright © 2003 John Wiley & Sons, Ltd.
HIV‐1 integrase inhibitory substances from Coleus parvifolius
Authors: Tewtrakul Supinya , Miyashiro Hirotsugu , Nakamura Norio , Hattori Masao , Kawahata Takuya , Otake Toru , Yoshinaga Tomokazu , Fujiwara Tamio , Supavita Tanomjit , Yuenyongsawad Supreeya , Rattanasuwon Pranee , Dej‐Adisai Sukanya
Published: January 2005

For the purpose of discovering anti‐HIV‐1 agents from natural sources, water and EtOH extracts of 50 Thai plants were screened for their inhibitory activity against HIV‐1 integrase (IN), an enzyme essential for viral replication. Of these plants, an EtOH extract of Coleus parvifolius Benth. (aerial parts) showed potent activity against HIV‐1 IN with an IC50 value of 9.2 µg/mL. From this extract, 11 compounds were isolated and identiﬁed as luteolin 5‐O‐β‐d‐glucopyranoside (1), luteolin (2), luteolin 7‐methyl ether (3), luteolin 5‐O‐β‐d‐glucuronide (4), 5‐O‐β‐d‐glucopyranosyl‐luteolin 7‐methyl ether (5), rosmarinic acid (6), rosmarinic acid methyl ester (7), daucosterol (8), a mixture of α‐ and β‐amyrin (9, 10) and phytol (11). Of these compounds, rosmarinic acid methyl ester (7), rosmarinic acid (6), luteolin (2) and luteolin 7‐methyl ether (3) exhibited inhibitory activities against HIV‐1 IN with IC50 values of 3.1, 5.0, 11.0 and 11.0 µM, respectively. Among rosmarinic acid derivatives, the HIV‐1 IN inhibitory activity increased in turn for a dimer (IC50 = 5.0 µM), a trimer (IC50 = 1.4 µM), and a tetramer (IC50 = 1.0 µM). Copyright © 2003 John Wiley & Sons, Ltd.
Activity of Zanthoxylum clava‐herculis extracts against multi‐drug resistant methicillin‐resistant Staphylococcus aureus (mdr‐MRSA)
Authors: Gibbons Simon , Leimkugel Julia , Oluwatuyi Moyo , Heinrich Michael
Published: January 2005

In a continuing search for compounds with antibiotic activity against methicillin‐resistant Staphylococcus aureus (MRSA) possessing multidrug efﬂux systems, we have demonstrated activity associated with extracts from Southern prickly ash bark, Zanthoxylum clava‐herculis. Bioassay‐guided isolation of an alkaloid extract led to the characterization of the benzo[c]phenanthridine alkaloid chelerythrine as the major active principle. This compound exhibited potent activity against strains of MRSA, which were highly resistant to clinically useful antibiotics via multidrug efﬂux mechanisms. Copyright © 2003 John Wiley & Sons, Ltd.
Correction of the high blood viscosity syndrome by a mixture of diquertin and ascorbic acid in vitro and in vivo
Authors: Plotnikov M. B. , Aliev O. I. , Maslov M. Ju. , Vasiliev A. S. , Tjukavkina N. A.
Published: January 2005

Diquertin was shown to diminish blood viscosity, to decrease the aggregation of erythrocytes, and to increase their deformability using a model of the high blood viscosity syndrome in vitro. A mixture of Diquertin with Ascorbic Acid was more effective in improving rheological indicators of blood, then either Diquertin or Tanakan. On a model of chronic brain ischemia, which is accompanied by signiﬁcant deterioration of the rheological properties of blood, it was shown that a therapy with a mixture of Diquertin and Ascorbic Acid decreases the expression of the high blood viscosity syndrome. Copyright © 2003 John Wiley & Sons, Ltd.
In vitro cytotoxicity activity of diosquinone, a naphthoquinone epoxide
Authors: Adeniyi B. A. , Robert M. F. , Chai H. , Fong H. H. S.
Published: January 2005

Diosquinone [1], a naphthoquinone epoxide previously isolated from the root bark of Diospyros mespiliformis (Hostch) and D. tricolor [Ebenaceae] is been assessed for cytotoxicity activity against ten cancer cell lines by standard NIH method. The ethno‐pharmacological claim of this plant and the previously observed good antibacterial activity of this compound among the others isolated from this plant suggest its probable cytotoxicity activity.

Diosquinone was observed to be very active against most of the cancer cell lines. It shows very good activity against all the cell lines tested with ED50 value ranging between 0.18 µg/ml. against Human Glioblastoma (U373) to 4.5 µg/ml. against Hormone dependent human prostrate cancer( LNCaP). Copyright © 2003 John Wiley & Sons, Ltd.
Pharmacological activities of stromata of Cordyceps scarabaecola
Authors: Yu K. W. , Kim K. M. , Suh H. J.
Published: January 2005

The chemical components of freeze‐dried stromata from Cordyceps scarabaecola were examined. The stromata consisted of crude carbohydrates (55.1%) and crude proteins (14.2%). The stromata were also composed of a low content of crude ash (6.6%) and fat (1.5%). The composition of the carbohydrate in the stromata included a large quantity of glucose (46.6%), mannose (35.4%) and galactose (18.0%). The acidic amino acids such as glutamic acid (32.1 mg/g) and aspartic acid (24.7 mg/g) were present in a large quantity. The extracts of stromata did not reveal any inhibitory activity for AChE in vitro. It was observed that a hot‐water extract (HW) of the stromata contributed signiﬁcantly to the anticoagulant activity (60 s coagulating time) and anticomplementary activity (62% of ITCH50 value). The MeOH‐soluble fraction (M) from the freeze‐dried stromata inhibited TPA‐induced O2− generation as effectively as the positive control, genistine 27%. The hot‐water extract (HW) showed the most potent intestinal immune system modulation activity and the MeOH‐soluble fraction (M) had intermediate activity. Copyright © 2003 John Wiley & Sons, Ltd.
Mitigation of thyroxine‐induced hyperglycaemia by two plant extracts
Authors: Tahiliani Pankaj , Kar Anand
Published: January 2005

Extracts of Trigonella foenum‐graecum (TFG) seed and Allium sativum (AS) bulb were evaluated for their efﬁcacy to ameliorate l‐thyroxine (l‐T4) induced hyperglycaemia in rats. Simultaneously, the serum cholesterol concentration, a supporting parameter for thyroid function, was also estimated. Thyroxine treatment in rats (300 µg/kg b. wt./day) increased the levels of both the thyroid hormones, namely thyroxine (T4) and tri‐iodothyronine (T3) with a concomitant elevation in serum glucose concentration and a reduction in serum cholesterol level. Administration of TFG (220 mg/kg/day) and AS (500 mg/kg/day) extracts in hyperthyroid animals decreased the serum glucose concentration as well as the serum thyroid hormones. For comparison, propyl thiouracil (PTU), an antithyroid compound, was used as the standard at a daily dose of 10 mg/kg. The reductions in serum glucose and thyroid hormone concentrations in the plant extract treated groups were comparable to that in PTU treated animals. Our ﬁndings indicate that TFG seed and AS bulb extracts may prove to be effective in the treatment of thyroxine‐induced hyperglycaemia. Copyright © 2003 John Wiley & Sons, Ltd.
Toxicological effects of α‐solamargine in experimental animals
Authors: Al Chami Lina , Méndez Ramón , Chataing Bernardo , O'Callaghan James , Usubillaga Alfredo , LaCruz Luis
Published: January 2005

α‐Solamargine isolated from the fresh fruits of Solanum americanum Miller was studied for its toxicity. Lethality studies in rats showed a dose‐mortality relationship with a LD50 of 42 mg/kg body weight intraperitoneally. The chronic and subchronic toxicity investigations indicated that the size of the glycoalkaloid dose was more important than the total glycoalkaloid intake. No appreciable toxic effects were observed at doses below 35 mg/kg body weight as indicated by blood parameters, enzyme levels and histological sections of kidney, liver and cardiac muscle. α‐Solamargine did not affect the weight of the testes and epididymis or the number of spermatozoa but produced a slight irritation and congestion in the epididymis and testis at doses up to 50 mg/kg body weight. Copyright © 2003 John Wiley & Sons, Ltd.
Protective effect of Mangifera indica L. extract (Vimang®) on the injury associated with hepatic ischaemia reperfusion
Authors: Martínez Sánchez Gregorio , Rodríguez H. María A. , Giuliani Attilia , Núñez Sellés Alberto J. , Pons Rodríguez Niurka , Fernández Olga Sonia León , Re L.
Published: January 2005

The effect of Mangifera indica L. extract (Vimang®) on treatment of injury associated with hepatic ischaemia/reperfusion was tested. Vimang® protects from the oxidative damage induced by oxygen‐based free radicals as shown in several in vitro test systems conducted. The ability of Vimang® to reduce liver damage was investigated in rats undergoing right‐lobe blood ﬂow occlusion for 45 min followed by 45 min of reperfusion. The ischaemia/reperfusion model leads to an increase of transaminase (ALT and AST), membrane lipid peroxidation, tissue neutrophil inﬁltration, DNA fragmentation, loss of protein ‐SH groups, cytosolic Ca2+ overload and a decrease of catalase activity. Oral administration of Vimang® (50, 110 and 250 mg/kg, b.w.) 7 days before reperfusion, reduced transaminase levels and DNA fragmentation in a dose dependent manner (p < 0.05). Vimang® also restored the cytosolic Ca2+ levels and inhibited polymorphonuclear migration at a dose of 250 mg/kg b.w., improved the oxidation of total and non protein sulfhydryl groups and prevented modiﬁcation in catalase activity, uric acid and lipid peroxidation markers (p < 0.05). These data suggest that Vimang® could be a useful new natural drug for preventing oxidative damage during hepatic injury associated with free radical generation. Copyright © 2003 John Wiley & Sons, Ltd.
Direct tandem mass spectrometric analysis of amino acids in dried blood spots without chemical derivatization for neonatal screening
Authors: Nagy Kornél , Takáts Zoltán , Pollreisz Ferenc , Szabó Teréz , Vékey Károly
Published: January 2005

Neonatal screening performed by electrospray tandem mass spectrometry is a powerful technique in clinical diagnostics. In the present paper an alternative to the widely accepted method involving butylation has been developed. In the new method butylation is not required, and multiple reaction monitoring (MRM) was used instead of constant neutral loss scanning. The method was optimized for detection of 23 L‐amino acids in their native form. Quantitation was based on isotope‐labeled internal standards, calibration curves were linear from 0 to 500 μmol/L, and detection limits were in the range 2–42 μmol/L. The utility of the present technique is illustrated in the case of one neonate suffering from citrullinaemia. Copyright © 2003 John Wiley & Sons, Ltd.
Tandem mass spectrometric analysis of glyphosate, glufosinate, aminomethylphosphonic acid and methylphosphinicopropionic acid
Authors: Goodwin Lee , Startin James R. , Goodall David M. , Keely Brendan J.
Published: January 2005

A detailed MSn study of glyphosate, glufosinate and their main metabolites, aminomethylphosphonic acid and methylphosphinicopropionic acid, using an ion trap mass spectrometer, was performed. The analytes show good response in negative ion electrospray mass spectrometry (ES‐MS) as [MH]− ions. Tandem‐MS spectra reveal a wealth of structurally specific ions, allowing characterisation of the fragmentation pathways of the four analytes in their native form for the first time. The ions formed at each stage of fragmentation reveal ions common to each analyte, such as phosphinate, as well as analyte specific transitions. Simplex optimisation allows optimum trapping and fragmentation parameters to be determined leading to improved response for particular transitions and transition sequences, and revealing previously unseen ions. Copyright © 2003 John Wiley & Sons, Ltd.
Identification of caffeic acid derivatives in Actea racemosa (Cimicifuga racemosa, black cohosh) by liquid chromatography/tandem mass spectrometry
Authors: Li Wenkui , Sun Yongkai , Liang Wenzhong , Fitzloff John F. , van Breemen Richard B.
Published: January 2005

Caffeic acid derivatives occurring in black cohosh [Cimicifuga racemosa (L.) Nutt., Actaea racemosa (Ranunculaceae)], some of which may have pharmacological activity, were analyzed using high‐performance liquid chromatography (HPLC) electrospray ionization tandem mass spectrometry (ESI‐MS/MS) with the aim of developing a methodology for their rapid identification in a complex plant matrix. Based on these studies, structurally characteristic product ions and neutral molecule losses were identified, which were then used during LC/MS/MS with product ion scanning, precursor scanning and constant neutral loss scanning to detect caffeic acid derivatives in a crude extract of black cohosh. Several caffeic acid derivatives were detected, and the identification of six of them were confirmed by comparison with authentic standards including caffeic acid, ferulic acid, isoferulic acid, fukinolic acid, cimicifugic acid A, and cimicifugic acid B. Four other compounds were detected that appeared to be caffeic acid derivatives based on LC/MS/MS retention times, molecular weights, and fragmentation patterns during MS/MS. Since standards were unavailable for these four compounds, they were tentatively identified using LC/MS/MS as cimicifugic acid E, cimicifugic acid F, dehydrocimicifugic acid A, and dehydrocimicifugic acid B. Dehydrocimicifugic acid A and dehydrocimicifugic acid B have not been reported previously to be constituents of black cohosh. Copyright © 2003 John Wiley & Sons, Ltd.
Secondary ion mass spectrometry and X‐ray photoelectron spectroscopy investigation on chemical vapor deposited CeO2ZrO2TiO2 thin films
Authors: Barison Simona , Barreca Davide , Battiston Giovanni A. , Daolio Sergio , Fabrizio Monica , Gerbasi Rosalba , Tondello Eugenio
Published: January 2005

Mixed CeO2ZrO2 systems have attracted widespread interest for their use in three‐way catalyst (TWC) technology for automotive exhaust conversion to non‐toxic products. In this work, CeO2ZrO2 thin films were deposited, via chemical vapor deposition, in order to obtain nanoscale materials with a high surface‐to‐volume ratio, with precise control of system properties. The addition of TiO2 as buffer layer was also investigated. Cordierite was chosen as substrate, being the usual refractory material for catalytic mufflers. The multilayers were characterized by scanning electron microscopy, X‐ray photoelectron spectroscopy (XPS) and secondary ion mass spectrometry (SIMS). In particular, the combination of SIMS and XPS allowed us to investigate both surface and in‐depth chemical composition, studying also film‐intermixing phenomena induced by annealing processes. Copyright © 2003 John Wiley & Sons, Ltd.
Nitrogen isotope analysis of ammonium in aqueous solutions using a perfluorosulfonated ionomer membrane for solid‐phase microextraction
Authors: Norlin Elin , Irgum Knut , Ohlsson K. E. Anders
Published: January 2005

The use of custom‐made solid‐phase microextraction (SPME) fibers coated with a perfluorosulfonated ionomer, Nafion®, was investigated for nitrogen isotopic analysis of ammonium in aqueous solutions. Aqueous ammonium was converted to ammonia by addition of a base, followed by absorption from the headspace, desorption in the injection port of a gas chromatograph, and analysis by gas chromatography/combustion/isotope ratio mass spectrometry (GC/C/IRMS). Fibers coated with a Nafion tubing were chosen due to a higher fiber‐gas distribution constant and a higher Nafion thickness than fibers coated with Nafion solution, both leading to a higher amount of ammonia absorbed at equilibrium. The Nafion membrane‐coated fiber absorbed approximately 20 times more than a commercial polydimethylsiloxane (PDMS) fiber. The isotopic fractionation between fiber and gas was 1.0117 ± 0.0009 (standard deviation, SD, of all measurements) at an initial ammonia gas concentration of 21–210 μM. At 390 μM initial gas concentration it was slightly lower. When sampling from liquid samples, an ammonium concentration of 10 mM was needed to obtain a sufficient amount of ammonia absorbed. Modeling of the absorption at different temperatures showed that the absorption was approximately constant in the temperature range suitable for SPME experiments. Absorption at room temperature was therefore used for simplicity. A pilot study was conducted in which absorption was achieved from a single 9 μL droplet of sample. The preliminary results showed that δ15N analysis was possible for only 0.4–0.5 μmol of ammonium with a SD of 0.8‰ (n = 5). Copyright © 2003 John Wiley & Sons, Ltd.
Mycosporine‐glutamicol‐glucoside: a natural UV‐absorbing secondary metabolite of rock‐inhabiting microcolonial fungi
Authors: Volkmann Marc , Whitehead Kenia , Rütters Heike , Rullkötter Jürgen , Gorbushina Anna A.
Published: January 2005

Microcolonial ascomycetes are known to inhabit bare rock surfaces in cold and hot deserts and thus are habitually exposed to high levels of solar radiation. Several of these stress‐tolerant fungal isolates, cultivated in the laboratory under daylight illumination, were studied for the presence of effective UV‐radiation protection substances. Liquid chromatography/mass spectrometry (LC/MS) and liquid chromatography/tandem mass spectrometry (LC/MS/MS) analyses allowed for efficient separation and structure clarification of two mycosporines. It was demonstrated that both mycosporine‐glutamicol‐glucoside and mycosporine‐glutaminol‐glucoside are natural and constitutive secondary metabolites of microcolonial fungi. The function and relation of these substances in the fungal cell are discussed. Copyright © 2003 John Wiley & Sons, Ltd.
Quadrupole time‐of‐flight versus triple‐quadrupole mass spectrometry for the determination of non‐steroidal antiinflammatory drugs in surface water by liquid chromatography/tandem mass spectrometry
Authors: Marchese Stefano , Gentili Alessandra , Perret Daniela , Ascenzo Giuseppe D' , Pastori Federico
Published: January 2005

A triple‐quadrupole instrument and a hybrid quadrupole/time‐of‐flight (TOF) mass spectrometer were compared for the determination of pharmaceutical compounds in water samples. The drugs investigated were the analgesics Ibuprofen, Fenoprofen, Ketoprofen, Naproxen, and Diclofenac. The recently introduced Q2‐pulsing function, which enhances the transmission of fragment ions of a selected m/z window from the collision cell into the TOF analyzer, improved the sensitivity of product ion scans on the quadrupole/TOF instrument. The selectivity is much better on quadrupole/TOF systems than on triple quadrupoles because the high resolving power of the reflectron‐TOF mass analyzer permits high‐accuracy fragment ion selection. This minimizes interferences from environmental matrices and allows acquisition of full spectra for selected analytes with better signal‐to‐noise characteristics than comparable spectra obtained with a scanned quadrupole. The qualitative information obtained (mass accuracy, resolution and full‐scan spectra) by hybrid quadrupole/TOF mass spectrometry allows a more certain identification of analytes in environmental matrices at trace levels. Sample enrichment of water samples was achieved by a solid‐phase extraction procedure. Average recoveries for loading 1 L of samples varied from 88 to 110%, and the quantification limits were less than 1.2 ng/L for the triple‐quadrupole instrument (in MRM mode) and less than 3 ng/L for the quadrupole/TOF instrument. Copyright © 2003 John Wiley & Sons, Ltd.
Existing demand for birth spacing in developing countries: perspectives from household survey data
Authors: Jansen William H.
Published: January 2005

Objective

To identify the extent of demand for birth spacing, according to age and parity among married women of reproductive age (MWRA) in developing countries.

Methods

Secondary analysis of data from the Demographic and Health Surveys (DHS) using cross‐tabulations. Data collected from nationally representative samples of MWRA in selected developing countries between 1990 and 2004.

Results

Demand for birth spacing is the most prevalent reason for an interest in family planning among married women aged 15–29 years in the majority of developing countries examined. In the 15–19‐year age cohort, the demand for spacing is proportionally the most prevalent reason for a demand for family planning. A demand for spacing even exists among young, zero‐parity married women in each country examined. Findings on the demand for spacing among zero‐parity married women quantifies the expressed desire of some married women in developing countries to postpone a first birth or the timing of a first pregnancy.

Conclusion

The substantial demand for birth spacing among young, low‐ and zero‐parity women suggests that family planning programs in developing countries may need to reevaluate how accessible services are for this cohort of potential contraception users. Currently, many service‐delivery protocols, counseling practices and service provider training may not fully address the needs of younger, low‐ or zero‐parity clients.
Soft forceps
Authors: Roshan D.F. , Petrikovsky B. , Sichinava L. , Rudick B.J. , Rebarber A. , Bender S.D.
Published: January 2005

Objective

The risk of maternal and fetal trauma and, chiefly, the fear of law suits, have contributed to a significant decline in rates of forceps‐assisted deliveries and an increase in rates of cesarean sections, especially in the United States. Our experience with gas‐sterilized forceps blades covered with a soft rubber coating–the “soft” forceps–is described.

Method

Ninety‐six women who required a forceps‐assisted delivery for standard indications were randomly allocated to 2 groups. There were 51 women in the regular forceps group and 45 women in the soft forceps group. Low forceps delivery with a Simpson instrument was used in all cases. The groups were compared for fetal injury.

Results

The rates of severe facial abrasion and minimal marking were 4.1% and 61%, respectively, in the regular forceps group and 1.9% and 34% in the soft forceps group.

Conclusion

The soft forceps may reduce the rates of neonatal facial abrasion and skin bruises. The forceps should be further perfected, as well as vacuum extractors; they should both continue to be part of the obstetrician's armamentarium.