bluuebunny/crossref_metadata_2025_split huggingface dataset:
Test Amnioinfusion to Determine Suitability for Serial Therapeutic Amnioinfusion in Midtrimester Premature Rupture of Membranes
Authors: Tan L.-K. , Kumar S. , Jolly M. , Gleeson C. , Johnson P. , Fisk N.M. 
Published: April 2003

<i>Objective:</i> To evaluate whether a test amnioinfusion procedure is useful in selecting cases of midtrimester preterm premature rupture of membranes (PPROM) which may benefit from serial amnioinfusions if the initial fluid is retained. <i>Study Design:</i> The Centre for Fetal Care database between 1992 and 2000 was reviewed for women with PPROM <26 weeks who had undergone amnioinfusion. Amniotic fluid index (AFI) was assessed before and after a test amnioinfusion procedure. Those who retained fluid ≧48 h underwent serial AFI assessment with a view to serial amnioinfusion when oligohydramnios recurred. <i>Results:</i> Eighty-five amnioinfusion procedures were performed in 60 women with oligohydramnios. Nineteen of these women presented with confirmed PPROM at a median gestation of 19 (range 15–22) weeks and severe olighohydramnios (median AFI 1, range 0–3 cm), in whom 20 test amnioinfusions were carried out. Two amnioinfusions were abandoned during the procedure because of fetal bradycardia and both mothers opted for termination of pregnancy. Only 4 women retained fluid during the test amnioinfusion, 1 of whom miscarried at 19 weeks before serial amnioinfusion could be started. The remaining 3 underwent a median of 4 (range 1–6) serial amnioinfusion procedures; none had evidence of pulmonary hypoplasia. Thirteen (68%) leaked fluid within 48 h; within this group there was 1 subsequent miscarriage and 9 pregnancy terminations. The remaining 3 pregnancies resulted in livebirths 2 of which had pulmonary hypoplasia with 1 early neonatal death. Overall survival was poor (4/19), largely attributed to the high incidence of terminations in the presence of persistent severe oligohydramnios. In continuing pregnancies reaching viability survival was 67% (4 of 6). <i>Conclusion:</i> Three quarters of women with mid-trimester PPROM lose fluid at test amnioinfusion and therefore would not be suitable candidates for serial amnioinfusion. However, if infused fluid is retained, this allows subsequent serial amnioinfusion and prolongation of pregnancy in about 75%, with an attendant decrease in the risk of pulmonary hypoplasia. However, even successful serial amnioinfusion remains associated with procedure-related complications (i.e. chorioamnionitis, placental abruption) which themselves may predispose to preterm delivery.
Influence of upper‐tropospheric inertial stability on the convective transport of momentum
Authors: Mecikalski J. R. , Tripoli G. J. 
Published: April 2003

AbstractThis study verifies the apparent high positive correlation between environmental and convection‐relative inertial stability, and the transport of momentum by deep convection. We evaluate the hypothesis that convection structurally aligns itself to best access the region of lowest upper‐tropospheric inertial stability, while forming the lowest convective updraught‐relative inertial stability.A numerical experiment evaluates variations in the structure, behaviour and momentum‐transport characteristics of deep convection across the tropical‐plume genesis region in the eastern Pacific. This unique region forms as a precursor to tropical‐plume genesis, and possesses spatially varying very‐low upper‐tropospheric inertial stability (the potential vorticity locally reaches zero, or becomes slightly negative, in the northern hemisphere).Our results show that the vertical transport of horizontal momentum is predictable, given knowledge of the inertial‐stability fields immediately surrounding the convection. It is conjectured that the preferred mode of convective organization (squall‐line dominated versus more three‐dimensional) near the intertropical convergence zone is a function of the ambient inertial stability. Therefore, as the convection organizes itself, it selects the most efficient access to regions of lowest inertial stability to enable its upper‐tropospheric outflow. Copyright © 2003 Royal Meteorological Society
Vulcanization kinetics of natural rubber–organoclay nanocomposites
Authors: López‐Manchado M. A. , Arroyo M. , Herrero B. , Biagiotti J. 
Published: April 2003

AbstractThe effect of the incorporation of a bentonite on the vulcanization kinetics of natural rubber was investigated by means of both cure‐meter testing and differential scanning calorimetry (DSC) under dynamic and isothermal conditions. The vulcanization curves showed that the modified clay behaved as an effective vulcanizing agent, accelerating the vulcanization reaction of the elastomer. A marked decrease in the induction time and optimum cure time of the elastomer were observed in the presence of the organoclay. Although the octadecylamine itself accelerated the vulcanization process, the octadecylamine‐modified clay gave rise to a further noticeable increase in the vulcanization rate, which could be attributed to a synergetic effect between the filler and the amine. Moreover, in the presence of the organoclay, a dramatic increase in the torque value was obtained because of the formation of a higher number of crosslinks, which could be attributed to the confinement of the elastomer chains within the silicate galleries and, consequently, to better interactions between the filler and the rubber. However, no significant changes were observed in the unmodified clay composite. These results were in concordance with those obtained by DSC. In addition, the activation energy of the vulcanization process was also calculated by means of both techniques. A clear decrease in the activation energy was observed when the organoclay was added to the nanocomposite, which indicated that the layered silicate favored the processing of the elastomer. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 89: 1–15, 2003
Development of a toughened DGEBS/DDS system toward improved thermal and mechanical properties by the addition of a tetrafunctional epoxy resin and a novel thermoplastic
Authors: Blanco Ignazio , Cicala Gianluca , Faro Carmelo Lo , Recca Antonio 
Published: April 2003

AbstractIt was the object of the present article to discuss the effect of the addition of a tetrafunctional resin, namely, tetraglycidyl‐4,4′‐diaminodiphenylmethane (TGDDM), and of a novel 40:60 polyethersulfone:polyetherethersulfone (PES:PEES) copolymer on a blend constituted by a difunctional resin, diglycidyl ether of bisphenol S (DGEBS), and an aromatic ammine, 4,4′‐diaminodiphenylsulfone (4,4′DDS). The formulated blends were fully characterized in terms of the morphology and the viscoelastic and mechanical properties. The modification by the tetrafunctional resin was proved to be a useful means to improve the glass transition temperature and, therefore, to widen the range of the working temperature. The addition of the novel copolymer resulted in a marked increase in toughness without negatively affecting the thermal and elastic properties of the blend. TEM analysis, despite the high amount of thermoplastic used, showed a homogeneous morphology that would lead to the conclusion of the existence of a full‐IPN network. Moisture‐uptake experiments were conducted both on the blend and on the resins on their own. It was shown that the combination of the difunctional resin with the tetrafunctional led to a decrease of the percent of the water absorbed. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 89: 268–273, 2003
Study on adsorption behavior between Cr(VI) and crosslinked amphoteric starch
Authors: Xu Shi‐Mei , Zhang Shu‐Fen , Lu Rong‐Wen , Yang Jin‐Zong , Cui Chang‐Xi 
Published: April 2003

AbstractCrosslinked amphoteric starches (CASs) with quaternary ammonium cationic and carboxymethyl anionic groups were prepared by a hemidry reaction. Their adsorption behavior for Cr(VI) was investigated, and was found to follow the Langmuir isotherm. The adsorption process was found to be dependent on initial pH, concentration of Cr(VI), dose of CAS, and temperature. The adsorption capacity decreased with increasing degree of substitution of anionic groups. The thermodynamic study indicated that the adsorption process was exothermic, and the enthalpy changes (ΔHθ), the entropy changes (ΔSθ), and free energy changes (ΔGθ) for CASs were determined. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 89: 263–267, 2003
Development of a maize molecular evolutionary genomic database
Authors: Du Chunguang , Buckler Edward , Muse Spencer 
Published: April 2003

AbstractPANZEA is the first public database for studying maize genomic diversity. It was initiated as a repository of genomic diversity for an NSF Plant Genome project on ‘Maize Evolutionary Genomics’. PANZEA is hosted at the Bioinformatics Research Center, North Carolina State University, and is open to the public (http://statgen.ncsu.edu/panzea). PANZEA is designed to capture the interrelationships between germplasm, molecular diversity, phenotypic diversity and genome structure. It has the ability to store, integrate and visualize DNA sequence, enzymatic, SSR (simple sequence repeat) marker, germplasm and phenotypic data. The relational data model is selected and implemented in Oracle. An automated DNA sequence data submission tool has been created that allows project researchers to remotely submit their DNA sequence data directly to PANZEA. On‐line database search forms and reports have been created to allow users to search or download germplasm, DNA sequence, gene/locus data and much more, directly from the web. Copyright © 2003 John Wiley & Sons, Ltd.
Dlx‐1 and Dlx‐2 expression in the adult mouse brain: Relationship to dopaminergic phenotypic regulation
Authors: Saino‐Saito Sachiko , Berlin Roseann , Baker Harriet 
Published: April 2003

AbstractExpression of the homeodomain‐containing transcription factors Dlx‐1 and Dlx‐2 in the lateral (LGE) and medial (MGE) ganglionic eminences, subpallial embryonic structures, is required for generation of telencephalic interneurons. LGE‐ and MGE‐derived progenitors migrate and populate a number of forebrain structures, including the cortex, hippocampus, and olfactory bulb (OB). Previous reports focusing on embryogenesis of telencephalic neurons in Dlx‐1 and Dlx‐2 null mice suggested a specific role for these genes in expression of the OB dopamine (DA) phenotype. We have investigated whether these genes also are expressed in adult brain, especially in those pallial derivatives, such as the OB, hippocampus, and possibly cortex, where neurogenesis continues in adults. With a highly sensitive, nonradioactive in situ hybridization technique and both DLX‐2 and pan DLX antisera, widespread expression of both genes was found in adult mouse fore‐ but not mid‐ or hindbrain. The adult unilateral naris closure paradigm was employed to establish a causative role for Dlx in regulating tyrosine hydroxylase (TH) expression; TH is the first enzyme in DA biosynthesis. TH mRNA, but not Dlx expression, was significantly down‐regulated in the OB ipsilateral to closure. These findings suggest that Dlx‐1 and ‐2 do not play a direct role in DA phenotypic differentiation and TH gene regulation in adult OB. The widespread expression of Dlx mRNA and protein in the adult brain suggests that these genes may have additional roles in mature animals. J. Comp. Neurol. 461:18–30, 2003. © 2003 Wiley‐Liss, Inc.
Topological charge of the real periodic finite‐gap Sine‐Gordon solutions
Authors: Grinevich P. G. , Novikov S. P. 
Published: April 2003

AbstractAn effective description of the inverse spectral data corresponding to the real periodic and quasi‐periodic finite‐gap (algebro‐geometrical) solutions for the sine‐Gordon equation is obtained. In particular, the explicit formula for the so‐called topological charge of the solutions is found and proven. As was already understood 20 years ago, it is very hard to extract any formula for this quantity from the Θ‐functional expressions. A new method was developed by the authors for this goal. In Appendix C an analogue of the Fourier‐Laurent integral transform on the Riemann surface is defined, based on the constructions of soliton theory. It is a natural continuous analogue of the discrete Krichever‐Novikov bases developed in the late 1980s for the needs of the operator quantization of string theory. © 2003 Wiley Periodicals, Inc.
Effect of pulsatile administration of levodopa on dyskinesia induction in drug‐naïve MPTP‐treated common marmosets: Effect of dose, frequency of administration, and brain exposure
Authors: Smith Lance A. , Jackson Michael J. , Hansard Matthew J. , Maratos Eleni , Jenner Peter 
Published: April 2003

AbstractLevodopa (L‐dopa) consistently primes basal ganglia for the appearance of dyskinesia in parkinsonian patients and 1‐methyl‐4‐phenyl‐1,2,3,6‐tetrahydropyridine hydrochloride (MPTP) ‐treated primates. This finding may reflect its relatively short duration of effects resulting in pulsatile stimulation of postsynaptic dopamine receptors in the striatum. We have compared the relationship between L‐dopa dose and frequency of administration on dyskinesia initiation in drug‐naïve, MPTP‐treated common marmosets. We have also studied the effect of increased brain exposure to pulsatile administration by combining a low‐dose of L‐dopa with the peripheral catechol‐O‐methyltransferase inhibitor (COMT‐I), entacapone. Pulsatile administration of a low (dose range, 5.0–7.5 mg/kg p.o.) or a high (12.5 mg/kg) dose of L‐dopa plus carbidopa b.i.d. produced a dose‐related reversal of motor deficits. Repeated administration of low and high doses of L‐dopa for 26 days to drug‐naïve, MPTP‐treated animals also caused a dose‐related induction of peak‐dose dyskinesia. Repeated administration of high‐dose L‐dopa b.i.d. compared to once daily caused a frequency‐related improvement of motor symptoms, resulting in a more rapid and initially more intense appearance of peak‐dose dyskinesia. Administration of low‐dose L‐dopa b.i.d. for 26 days in combination with entacapone enhanced the increase in locomotor activity and reversal of disability produced by L‐dopa alone, but with no obvious change in duration of L‐dopa's effect. However, combining entacapone with L‐dopa resulted in the more rapid appearance of dyskinesia, which was initially more severe than occurred with L‐dopa alone. Importantly, increasing pulsatile exposure of brain to L‐dopa by preventing its peripheral breakdown also increases dyskinesia induction. © 2003 Movement Disorder Society
Effect of short glass fiber on structure and viscoelastic behavior of olefinic polymers synthesized with metallocene catalyst
Authors: Martínez‐Burgos J. M. , Benavente R. , Pérez E. , Cerrada M. L. 
Published: April 2003

AbstractSeveral composites were prepared on the basis of an ethylene homopolymer and different copolymers of ethylene and 1‐hexene, synthesized with a metallocene catalyst, as matrices and a content of a 5 wt % of short glass fiber. The effect of the fiber incorporation on the structure and mechanical and viscoelastic behaviors was analyzed for the different samples. The glass fibers induced a slightly higher crystallinity, and the crystallite morphology significantly changed (long spacings and crystal orientation). The incorporation of fibers did not reinforce the different matrices under study at this low content; consequently, the mechanical parameters, such as Young's modulus, yielding stress, and microhardness, were lower in the composites as compared with those values found in the neat polyolefins. The location and apparent activation energies of distinct relaxation processes are also discussed. © 2003 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 41: 1244–1255, 2003
DNA degradation by water extract of green tea in the presence of copper ions: implications for anticancer properties
Authors: Malik Arshi , Azam Sonish , Hadi Naghma , Hadi S. M. 
Published: April 2003

AbstractIn recent years a number of reports have documented the chemopreventive effect of green tea consumption on various types of cancers such as those of bladder, prostate, esophagus and stomach. This property is attributed to the presence in green tea of polyphenols known as catechins. These include epigallocatechin‐3‐gallate, epigallocatechin and epicatechin. In addition to their antioxidant properties plant derived polyphenolics are also capable of oxidative DNA damage particularly in the presence of transition metal ions. We have recently proposed a mechanism for cytotoxic action of plant‐derived polyphenols against cancer cells that involves mobilization of endogenous copper and consequent prooxidant action. In partial support of the idea, in the present paper we show that water extract of green tea is considerably more efﬁcient than black tea extract in DNA cleavage in the presence of copper ions. Green tea extract also shows a higher rate of Cu(II) reduction and consequent hydroxyl radical formation. Cu(II) reduction is presumably accompanied by the formation of ‘oxidized species’ of tea polyphenols, which in turn also appear to catalyze the reduction of Cu(II) leading to redox cycling of copper ions. The results are discussed in relation to the structural differences between polyphenols of green and black tea. Copyright © 2003 John Wiley & Sons, Ltd.
Antinociceptive, antiinﬂammatory and acute toxicity effects of Salvia leriifolia Benth. seed extract in mice and rats
Authors: Hosseinzadeh Hossein , Haddadkhodaparast Mohammad H. , Arash Ali R. 
Published: April 2003

AbstractThe antinociceptive and antiinﬂammatory effects as well as the acute toxicity of Salvia leriifolia aqueous seed extract were studied in mice and rats. Antinociceptive activity was assessed using the hot‐plate and tail ﬂick tests. The effect on acute inﬂammation was studied using vascular permeability increased by acetic acid and xylene‐induced ear oedema in mice. The activity against chronic inﬂammation was assessed using the cotton pellet test in rats. The LD50 of the extract was found to be 19.5 g/kg (i.p.) in mice. The aqueous seed extract showed signiﬁcant and dose‐dependent (1.25–10 g/kg) antinociceptive activity over 7 h, and was inhibited by naloxone pretreatment. Signiﬁcant and dose‐dependent (2.5–10 g/kg) activity was observed against acute inﬂammation induced by acetic acid and in the xylene ear oedema test. In the chronic inﬂammation test the extract (2.5–5 g/kg) showed signiﬁcant and dose‐dependent antiinﬂammatory activity. The aqueous seed extract of S. leriifolia may therefore have supraspinal antinociceptive effects which may be mediated by opioid receptors, and showed considerable effects against acute and chronic inﬂammation. Copyright © 2003 John Wiley & Sons, Ltd.
Strategic operations management decisions and professional performance in U.S. HMOs
Authors: Heineke Janelle 
Published: April 2003

AbstractProfessional service organizations are becoming an increasingly important segment of the service sector in the U.S. but little attention has been paid to the management of these organizations, particularly in relation to technical performance. This paper reports the findings of a survey of managers of Health Maintenance Organizations (HMOs) which related operations management decisions about organization, workforce management, quality management and planning and control, to clinical process and outcome performance.This research demonstrates that managerial decisions do affect clinical performance in HMOs. These findings have implications for both researchers and practitioners. For researchers, the study provides a framework for future research on the important link between management decisions and technical performance in professional service organizations. For practitioners, this study suggests that technical performance will be enhanced when professional work is appropriately managed.
Synapse selection based on differences in synapse turnover
Authors: Thompson Jeffrey M. , Eisenbarth George S. , Ruffolo Robert R. , Nirenberg Marshall 
Published: April 2003

AbstractRat retinal neurons formed transient synapses with rat muscle cells in culture only during a discrete period in development, from the 20th day of embryonic development to the 7th neonatal day. In contrast, chick embryo spinal cord neurons formed synapses at all developmental stages tested, from the 2nd to the 18th day of embryonic development. The percentage of cells from the spinal cord that formed synapses with muscle cells was maximum at 4 days of embryonic development and decreased thereafter. However, the number of synapses with muscle formed by cells from 8‐day embryonic spinal cord did not decrease during 14 days of culture. Under identical conditions, all synapses formed between rat retinal neurons and muscle cells were terminated during 7 days of culture. These results show that differences in the rates of turnover of two populations of cholinergic synapses can result in the selective retention of one population of synapses and the loss of the other, and thereby alter the specificity of synaptic connections.
Serotonin as a stimulator of hippocampal cell differentiation in tissue culture
Authors: Gromova H. A. , Chubakov A. R. , Chumasov E. I. , Konovalov H. V. 
Published: April 2003

AbstractThe effects of serotonin (5‐HT) on morphofunctional development of hippocampal cultures derived from newborn rats were studied. It was established that systematic addition of 5‐HT to nutrient medium during cultivation stimulates neuropil development, axon myelination and synaptogenesis. Electrophysiological studies of hippocampal cells in 5‐HT treated cultures showed earlier exhibition of spontaneous activity and an increased number of spontaneously firing neurons and prevalence of periodic (bursting) type of discharges. These results indicate that 5‐HT stimulates the differentiation of hippocampal cells in tissue culture.
Immunohistochemical and biochemical approaches to the development of neuroglia in the CNS, with special reference to cerebellum
Authors: Ghandour M. S. , Langley O. K. , Clos J. 
Published: April 2003

AbstractImmunocytochemical methods have in recent years played a more important role in investigations of the development and function of glial cells in the nervous system because of their potential to distinguish between different cell populations. This short review attempts to highlight the value of this approach and summarizes the major cell‐type markers currently available. These include, for the astrocyte, GFA protein, S‐100 protein, vimentin, αα‐enolase and α‐2 glycoprotein. For the oligodendrocyte, myelin basic protein, the Wolfgram proteins, 2′,3′‐cyclic nucleotide 3′‐phosphohydrolase, myelin associated glycoprotein, proteolipid protein, galactocerebroside, carbonic anhydrase and glycerol 3‐phosphate dehydrogenase and other glial cell markers recognized by monoclonal antibodies are discussed. The application of these techniques to the study of the developing brain (and in particular the rodent cerebellum) are reviewed. It has proved possible to follow the development of distinct populations of astrocytes and oligodendrocytes from a very precocious age to the adult situation, thus providing new insight on the relationship between glial cells and neurons during normal and abnormal histogenesis.