bluuebunny/crossref_metadata_2025 huggingface dataset:
Role of nova‐1 in regulating α2N, a novel glycine receptor splice variant, in developing spinal cord neurons
Authors: Kumar David V. , Nighorn Alan , St. John Paul A.
Published: September 2002

Inhibitory glycine receptor (GlyR) subunits undergo developmental regulation, but the molecular mechanisms of GlyR regulation in developing neurons are little understood. Using RT‐PCR, we investigated the regulation of GlyR α‐subunit splice forms during the development of the spinal cord of the rat. Experiments to compare the amounts of mRNA for two known splice variants of the GlyR α2 subunit, α2A and α2B, in the developing rat spinal cord revealed the presence of an additional, novel variant that lacked any exon 3, herein named “α2N.” Examination of the RNA from spinal cords of different‐aged rats showed a dramatic down‐regulation of α2N during prenatal development: α2N mRNA formed a significant portion of the α2 subunit pool at E14, but its relative level was reduced by 85% by birth and was undetectable in adults. Two proteins previously implicated in regulating the splicing of GlyR α2 pre‐mRNA, the neurooncological ventral antigen‐1 (Nova‐1) and the brain isoform of the polypyrimidine tract binding protein (brPTB), underwent small changes over the same period that did not correlate directly with the changes in the level of α2N, calling into question their involvement in the developmental regulation of α2N. However, treatment of spinal cord neurons in culture with antisense oligonucleotides designed selectively to knock down one of three Nova‐1 variants significantly altered the relative level of GlyR α2N, showing that Nova‐1 isoforms can regulate GlyR α2 pre‐mRNA splicing in developing neurons. These results provide evidence for a novel splice variant of the GlyR α2 subunit that undergoes dramatic developmental regulation, reveal the expression profiles of Nova‐1 and brPTB in the developing spinal cord, and suggest that Nova‐1 plays a role in regulating GlyR α2N in developing neurons. © 2002 Wiley Periodicals, Inc. J Neurobiol 52: 156–165, 2002
Cloning of the cDNA and mRNA expression of CLRP, a complex leucine repeat protein of the golgi apparatus expressed by specific neurons of the rat brain
Authors: Pérez‐Márquez Julio , Reguillo Begoña , Paniagua Ricardo
Published: September 2002

We report the molecular cloning of one novel cDNA isolated from the rat brain. We have named the putative protein CLRP, for complex leucine‐repeat protein. The predicted CLRP amino acid sequence shares homology in the amino acid composition with the Galactose, N‐Acetylglucosamine, and Sialic acid transporters, and shows 91% identity with the sequence of one human chromosome 5 BAC clone. Expression of the CLRP cDNA tagged with GFP in COS‐7 cells was found in cell organelles that resemble the Golgi apparatus of the cytoplasm. In Northern blot, the CLRP probe labels a single band of 2.4 kb in the brain, kidney, lung, testis, and prostate. In the brain, CLRP mRNA is expressed by limited sets of neurons, such as the pyramidal cells of the cortex, the Purkinje cells of the cerebellum, and the motoneurons of the brainstem. In the brain, the CLRP mRNA is expressed at embryonic day 15; levels of expression are maintained until postnatal day 10 and decrease in adults. The results suggest that CLRP codes a novel member of the nucleotide–sugar family of proteins of the Golgi apparatus. © 2002 Wiley Periodicals, Inc. J Neurobiol 52: 166–173, 2002
Synaptic inputs onto spiking local interneurons in crayfish are depressed by nitric oxide
Authors: Aonuma Hitoshi , Newland Philip L.
Published: September 2002

We have analyzed the action of nitric oxide on the synaptic inputs of spiking local interneurons that form part of the local circuits in the terminal abdominal ganglion of the crayfish, Pacifastacus leniusculus. Increasing the availability of NO in the ganglion by bath applying the NO donor SNAP, or the substrate for its synthesis, L‐arginine, caused a depression of synaptic inputs onto the interneurons evoked by electrically stimulating mechanosensory neurons in nerve 2 of the terminal ganglion. Conversely, reducing the availability of NO by bath application of an NO scavenger, PTIO, and an inhibitor of nitric oxide synthase, L‐NAME, increased the amplitude of the evoked potentials. These results suggest that elevated NO concentration causes a depression of the synaptic inputs to spiking local interneurons. To determine whether these effects could be mediated through an NO/cGMP signaling pathway we bath applied a membrane permeable analogue of cGMP, 8‐br‐cGMP, which decreased the amplitude of the inputs to the interneurons. Bath application of an inhibitor of soluble guanlylyl cyclase, ODQ, produced an increase in the amplitude of the synaptic inputs. Our results suggest that NO causes a depression of synaptic inputs to spiking local interneurons probably by acting through an NO/cGMP signaling pathway. Moreover, application of NO scavengers modulates the inputs to these interneurons, suggesting that NO is continuously providing a powerful and dynamic means of modulating the outputs of local circuits. © 2002 Wiley Periodicals, Inc. J Neurobiol 52: 144–155, 2002
Die shape design optimization of sheet metal stamping process using meshfree method
Authors: Kim Nam Ho , Choi Kyung Kook , Chen Jiun Shyan
Published: September 2002

A die shape design sensitivity analysis (DSA) and optimization for a sheet metal stamping process is proposed based on a Lagrangian formulation. A hyperelasticity‐based elastoplastic material model is used for the constitutive relation that includes a large deformation effect. The contact condition between a workpiece and a rigid die is imposed through the penalty method with a modified Coulomb friction model. The domain of the workpiece is discretized by a meshfree method. A continuum‐based DSA with respect to the rigid die shape parameter is formulated using a design velocity concept. The die shape perturbation has an effect on structural performance through the contact variational form. The effect of the deformation‐dependent pressure load to the design sensitivity is discussed. It is shown that the design sensitivity equation uses the same tangent stiffness matrix as the response analysis. The linear design sensitivity equation is solved at each converged load step without the need of iteration, which is quite efficient in computation. The accuracy of sensitivity information is compared to that of the finite difference method with an excellent agreement. A die shape design optimization problem is solved to obtain the desired shape of the workpiece to minimize spring‐back effect and to show the feasibility of the proposed method. Copyright © 2001 John Wiley & Sons, Ltd.
Computability in non‐linear solid mechanics
Authors: Belytschko T. , Mish K.
Published: September 2002

The computability of non‐linear problems in solid and structural mechanics problems is examined. Several factors which contribute to the level of difficulty of a simulation are discussed: the smoothness and stability of the response, the required resolution, the uncertainties in the load, boundary conditions and initial conditions and inadequacies and uncertainties in the constitutive equation. An abstract measure of the level of difficulty is proposed, and some examples of typical engineering simulations are classified by this measure. We have put particular emphasis on engineering calculations, where many of the factors that diminish computability play a prominent role. Copyright © 2001 John Wiley & Sons, Ltd.
The effect of combined systemic administration of morphine and L‐NAME, a nitric oxide synthase inhibitor, on behavioral signs of neuropathic pain in rats
Authors: Ulugol Ahmet , Aslantas Aysegul , Karadag Hakan C. , Bulbul Ebru D. , Tuncer Alev , Dokmeci Ismet
Published: September 2002

The controversy over using opiods for managing chronic neuropathic pain is widely acknowledged, and nitric oxide (NO) is suggested to play an important role in the maintenance of the behavioral signs of neuropathic pain. We evaluated the effect of combined systemic administration of morphine and NG‐nitro‐L‐arginine‐methyl ester (L‐NAME), a NO synthase (NOS) inhibitor, on allodynia in the spinal nerve ligation model of pain in rats. Nerve injury was produced by tight ligation of the left L5 and L6 spinal nerves and this procedure resulted in neuropathic pain behaviors in the ipsilateral hindlimb. Mechanical and cold allodynia were detected, respectively, by application of von Frey filaments or acetone to the plantar surface of the foot. Morphine (0.1–10 mg/kg, i.p.) and L‐NAME (3–30 mg/kg, i.p.) reduced mechanical and cold allodynia with their higher doses. Combining subthreshold dose of L‐NAME (3 mg/kg, i.p.) with morphine, an appreciable increase in the antiallodynic effect of morphine was observed. This effect was prevented by L‐arginine (500 mg/kg, i.p.) and naloxone (1 mg/kg, i.p.). These results suggest that combining morphine with a NOS inhibitor may be a promising approach in the treatment of neuropathic pain.
Length effect during word and pseudo‐word reading. An event‐related fMRI study
Authors: Baciu Monica , Ans Bernard , Carbonnel Serge , Valdois Sylviane , Juphard Alexandra , Pachot‐Clouard Mathilde , Segebarth Christoph
Published: September 2002

This event‐related fMRI study has assessed the cerebral activations obtained during the reading of words and of pseudo‐words of varying length (one, two and three syllables). Eight right‐handed volunteers were examined. A pseudo‐randomized fMRI paradigm with six types of stimuli was applied and the SPM'99 software was used for data processing. The number of cerebral regions involved in reading increased with the stimulus length, both for words and for pseudo‐words. This concerned not only regions related to sensory‐motor aspects of reading but also regions related to more “central” language processes. Independently of the length, the reading of words and of pseudo‐words activated the same regions, an observation consistent with the connectionist models for reading. Considering the length of the stimuli, we obtained significant differences, in terms of cerebral regions, only between polysyllabic words and pseudo‐words, not between monosyllabic words and pseudo‐words. These results are in line with the connectionist view of reading, especially with the multi‐trace connectivist model of Ans et al (3).
General theory of domain decomposition: Beyond Schwarz methods
Authors: Herrera Ismael , Yates Robert
Published: September 2002

Recently, Herrera presented a general theory of domain decomposition methods (DDM). This article is part of a line of research devoted to its further development and applications. According to it, DDM are classified into direct and indirect, which in turn can be subdivided into overlapping and nonoverlapping. Some articles dealing with general aspects of the theory and with indirect (Trefftz–Herrera) methods have been published. In the present article, a very general direct‐overlapping method, which subsumes Schwarz methods, is introduced. Also, this direct‐overlapping method is quite suitable for parallel implementation. © 2001 John Wiley & Sons, Inc. Numer Methods Partial Differential Eq 17: 495–517, 2001
Contributions to the mathematics of the nonstandard finite difference method and applications
Authors: Anguelov Roumen , Lubuma Jean M.‐S.
Published: September 2002

We formalize the transfer of essential properties of the solution of a differential equation to the solution of a discrete scheme as qualitative stability with respect to the properties. This permits us to motivate some rules (viz. on the order of the difference equation, on the renormalization of the denominator of the discrete derivative, and on nonlocal approximation of nonlinear terms) used in the design of nonstandard finite difference schemes. Extensions of some models are considered, and numerical examples confirming the efficiency of the nonstandard approach are provided. © 2001 John Wiley & Sons, Inc. Numer Methods Partial Differential Eq 17: 518–543, 2001
Trajectories of cognitive recovery following a minor brain injury
Authors: Brewer Thomas L. , Metzger Bonnie L. , Therrien Barbara
Published: September 2002

Minor brain injury (MBI) is the most frequently diagnosed head trauma in the United States, with treatment costing more than $1.5 billion annually and many patients incapacitated for months following injury. The purpose of this study was to characterize the brain function disruptions associated with MBI and to determine the time trajectory of recovery, using a theoretical model of attention. Distractibility, impulsivity, irritability, and impaired executive functioning were demonstrated in all participants during the 24 hr after injury. Twenty percent of participants continued to complain of distractibility, impulsivity, and/or irritability throughout the 30‐day study. Loss of consciousness was shown to confound participants' healing trajectories. These results suggest that standard emergency room treatment following MBI is inadequate and should include discharge directives to reduce cognitive demands for at least 48 hr at a minimum, for 30 days or longer for those with loss of consciousness. © 2002 Wiley Periodicals, Inc. Res Nurs Health 25:269–281, 2002
Effect of the monomer and filler systems on the remineralizing potential of bioactive dental composites based on amorphous calcium phosphate
Authors: Skrtic D. , Antonucci J. M. , Eanes E. D.
Published: September 2002

Amorphous calcium phosphate (ACP), because of its high solubility and its rapid transformation to hydroxyapatite (HAP) in aqueous environments, has been utilized as the filler phase in the preparation of bioactive polymer‐based composites that have remineralization potential. The goal of this study was to evaluate the effects of chemical structure and compositional variations of seven photopolymerizable matrix monomer systems on the long‐term release of calcium and phosphate ions, i.e., their remineralizing potential, when used with three types of ACP filler systems: unhybridized ACP (u‐ACP), silica‐hybridized ACP (Si‐ACP), and zirconia‐hybridized ACP (Zr‐ACP) composites. The monomer systems evaluated were: 2,2‐bis[p‐(2′‐hydroxy‐3′‐methacryloxypropoxy)phenyl]‐propane (Bis‐GMA)/triethyleneglycol dimethacrylate (TEGDMA) [BT resin], Bis‐GMA/TEGDMA/­2‐hydroxyethyl methacrylate (HEMA) [BTH resin],­Bis‐GMA/TEGDMA/HEMA/zirconyl methacrylate (ZrMA) [BTHZ resin], TEGDMA/pyromellitic glycerol dimethacrylate (PMGDMA) [TP resin], a urethane dimethacrylate, [U], and two HEMA‐modified U resins with the mass fraction of 6.6% and 13.2% HEMA, ([U66H] and [U132H], respectively). All the visible light polymerizable composites consisted of 60% resin and 40% ACP filler on a mass fraction basis. It was shown that ion release from the immersed composites was affected by both the chemical structure and composition of the monomer system as well as the type of filler system. Whereas BT, U and U66H resins formulated with u‐ACP gave low to moderate levels of ion release, the resins with elevated amounts of HEMA (BTH, BTHZ and U132H) gave high and sustainable release of mineral ions. The remineralizing capacity of BT, U, U66H and U132H composites generally increased when hybridized fillers were employed instead of u‐ACP. Utilization of hybrid ACPs had, however, no effect on ion release from BTHZ composites. The TP composites initially gave high ion release, but it was not sustainable because of significant Ca‐binding by the matrix due to the high content of carboxylic acid groups derived from the PMGDMA comonomer. Copyright © 2001 John Wiley & Sons, Ltd.
Polyacid‐modified composite (compomer) systems containing polymers of N‐vinylpyrrolidone
Authors: Mitra S. B. , Wang B. , Rozzi S. M. , Clark T. R.
Published: September 2002

The objective of this work was to develop polyacid‐modified composite systems (compomers) suitable for dental restoratives in which high molecular weight hydrophilic (co)polymers containing variable amounts of N‐vinylpyrrolidone were incorporated in small amounts. It was expected that the added polymer would become part of a semi‐IPN (interpenetrating network) after the polymerizable components were cured. These systems could absorb water relatively rapidly at the early stages and thus provided good fluoride release. The effect of the addition of the high molecular hydrophilic polymers of varying compositions on the rheological, mechanical and thermal properties of the compomer systems was also investigated. The polymeric additive, significantly improved the rheological characteristics and without having any deleterious effect on the mechanical properties. The coefficient of thermal expansion of the compomers matched more closely with that of tooth structure when the N‐vinylpyrrolidone content of the polymeric additives was increased. Copyright © 2001 John Wiley & Sons, Ltd.
Effect of feed pressure on facilitated olefin transport through solid polymer electrolyte membranes1
Authors: Hong Seong Uk , Kim Jung Yong , Kang Yong Soo
Published: September 2002

Effect of feed pressure and anion properties on facilitated olefin transport through solid polymer electrolyte (SPE) membranes containing silver ions in poly(2‐ethyl‐2‐oxazoline) (POZ) or poly(N‐vinyl pyrrolidone) (PVP) matrix has been investigated. Propylene solubility data in various SPE films are analyzed using the dual sorption model. The results indicate that the solubility coefficient of propylene in polymeric matrices was unexpectedly high although it was unmeasurably low in corresponding pure polymer. The equilibrium constants of the reaction between carrier and propylene for SPE films containing AgBF4 are higher than those with AgCF3SO3 for both polymers investigated. In addition, saturated amounts of propylene coordinated to the silver ions in SPE films with AgBF4 are higher than those with AgCF3SO3, resulting in higher propylene permeance in polymer electrolytes containing AgBF4. Copyright © 2001 John Wiley & Sons, Ltd.
Albumin adsorption to surface of annealed fluorinated polyimide
Authors: Kawakami Hiroyoshi , Takahashi Takeo , Nagaoka Shoji , Nakayama Youichi
Published: September 2002

Albumin adsorption to a surface of fluorinated polyimide which was essentially created only by annealing treatment was investigated. After the polyimide surfaces were annealed, the morphology change of the surface was determined using atomic force microscopy and the surface properties were analyzed by contact angle measurements and X‐ray photoelectron spectroscopy. It was found that albumin adsorption on the surface strongly depended on the annealing temperature and time and decreased with annealing. The amount of albumin adsorption to the polyimide annealed at 250 °C for 100 hr was six‐fold smaller than that of polystyrene and polydimethylsiloxane. A decrease of surface free energy due to a decline in the polar and hydrogen bonding components and an increase in hydrophobicity on the polyimide surface by annealing explain the albumin adsorption results. Copyright © 2001 John Wiley & Sons, Ltd.
A comparison of several meso‐tetraalkyl cobalt porphyrins as catalysts for the electroreduction of dioxygen
Authors: Yuasa M. , Nishihara R. , Shi C. , Anson F. C.
Published: September 2002

A set of cobalt porphyrins containing alkyl substituents in their meso sites were synthesized and compared as catalysts for the electroreduction of O2 when adsorbed on the surface of graphite electrodes. The meso substituents examined included ethyl, propyl, n‐butyl and n‐pentyl. All but the last exhibited high catalytic activity for the electroreduction of O2 by four electrons. The catalytic activity was attributed to spontaneous aggregation of the porphyrins to produce structures in which pairs of cobalt centers could be bridged by O2 molecules as previously observed for the unsubstituted and tetramethyl analogs. Copyright © 2001 John Wiley & Sons, Ltd.
A systematic study of the microwave and thermal cure kinetics of the TGDDM/DDS and TGDDM/DDM epoxy‐amine resin systems†
Authors: Hill David J. T. , George Graeme A. , Rogers David G.
Published: September 2002

The microwave and thermal cure processes for the epoxy‐amine systems N,N,N′,N′‐tetraglycidyl‐4,4′‐diaminodiphenyl methane (TGDDM) with diaminodiphenyl sulfone (DDS) and diaminodiphenyl methane (DDM) have been investigated. The DDS system was studied at a single cure temperature of 433 K and a single stoichiometry of 27 wt% and the DDM system was studied at two stoichiometries, 19 and 32 wt%, and a range of temperatures between 373 and 413 K. The best values of the kinetic rate parameters for the consumption of amines have been determined by a least squares curve fit to a model for epoxy‐amine cure. The activation energies for the rate parameters for the MY721/DDM system were determined as was the overall activation energy for the cure reaction which was found to be 62 kJ mol−1. No evidence was found for any specific effect of the microwave radiation on the rate parameters, and the systems were both found to be characterized by a negative substitution effect. Copyright © 2001 John Wiley & Sons, Ltd.
UV cured transparent films including non‐aqueous conductive microgels
Authors: Kim Yang‐Bae , Kim Wha‐Suk , Yu Jeong‐A , Hong Jin‐Who
Published: September 2002

UV cured transparent films containing non‐aqueous conductive microgels coated with poly(aniline)/dodecyl benzenesulfonic acid(DBSA) were obtained. The conductive microgels were prepared by interface polymerization of aniline/DBSA in the presence of non‐aqueous polymeric microgels. The electrical conductivity and the particle size of the prepared conductive microgel were 0.5 S/cm and 58 nm, respectively. The prepared conductive microgels were easily blended with a UV curable coating formulation, and then were cured to make highly optically transparent films. For the UV cured film containing about 35 wt% of the conductive microgels, a surface resistance in the range of 107 to 108 Ω/square was obtained. In a polar cosolvent, such as NMP and m‐cresol, the critical volume was shifted to the lower range, with a value of 10 wt%. The UV cured films containing the conductive microgels exhibited good electrical stability against the thermal aging and humidity. Copyright © 2002 John Wiley & Sons, Ltd.
In vitro study on the drug release behavior from Polylactide‐based blend matrices
Authors: Cai Qing , Bei Jianzhong , Wang Shenguo
Published: September 2002

In this paper, several drug carriers were fabricated to release the hydrophilic 5‐fluorouracil (5‐Fu), such as blend of polylactide (PLA) with different molecular weights and blends of PLA with polycaprolactone (PCL) or poly(ethylene glycol) (PEG). The controlled release devices were processed into tablets containing 12.5 wt% of 5‐Fu, and the in vitro release studies were carried out under pH 7.4 at 37 ± 1 °C. The degradation of all the drug carriers were performed under the same conditions, parameters that changes of inherent viscosity, weight loss and water sorption were determined at predetermined time intervals with degradation. To inspect the morphology of the PLA‐based blends and its affect on the 5‐Fu release behavior thereof, scanning electron microscopy (SEM) and X‐ray diffraction techniques were applied. As a result, the two‐phasic release behavior of homo‐PLA was significantly ameliorated in all the cases by the initial time lag period being eliminated or shortened. And a linear 5‐Fu release behavior was obtained from blend of PLAs with different molecular weights. Copyright © 2002 John Wiley & Sons, Ltd.
Graft copolymerization ofN‐vinyl‐pyrrolidone and acrylamide on cellulose derivatives: synthesis, characterization and study of their biological effect
Authors: Flefel Eman M. , Ibrahim Maha M. , El‐Zawawy Waleed K. , Ali Amal M.
Published: September 2002

Graft copolymers of carboxymethyl cellulose and hydroxyethyl cellulose with N‐vinyl‐2‐pyrrolidone and acrylamide have been synthesized by grafting copolymer of N‐vinyl‐2‐pyrrolidone and acrylamide onto a mixture of carboxymethyl cellulose and hydroxyethyl cellulose by a solution polymerization technique using a redox initiation system. The graft copolymers were characterized by 13C‐NMR spectroscopy and scanning electron microscopy. These graft copolymers have been tested for their biodegradability and biological activity. None of the graft copolymer solutions shows any microbial degradation up to 10 days. The reported results are evidence of the possibility of anti‐fungi effect. Copyright © 2002 John Wiley & Sons, Ltd.
Photo‐alignment material with azobenzene‐functionalized polymer linked in film
Authors: Watanabe Hirohmi , Miyagawa Nobukazu , Takahara Shigeru , Yamaoka Tsuguo
Published: September 2002

Application of a new azo‐polymer as a photo‐alignment material for liquid crystals (LCs) was demonstrated. 4‐(Vinyloxyethyloxy)azobenzene (VAZO), which has thermally reactive vinyl ether groups, reacted with the OH groups of poly(4‐hydroxystyrene) (PHS) during the baking process. The azo‐attached polymer (PHS‐VAZO) film showed anisotropic spectra after exposure to 365‐nm linear polarized light (LPL) unlike the VAZO‐doped poly(methylmethacrylate) (PMMA) film. The anisotropy of the film was small at high concentration of the azo‐chromophore because of thermal randomization of the polarized state. In the evaluation of photo‐alignment of the LC, the LC hybrid cell using the PHS‐VAZO film achieved high LC alignment. The azo‐attached polymer using the thermal reaction of vinyl ethers is useful for a photo‐alignment material. Copyright © 2002 John Wiley & Sons, Ltd.
Rapid method for determining malondialdehyde as secondary oxidation product in palm olein system by Fourier transform infrared spectroscopy
Authors: Mirghani M. E. S. , Man Y. B. Che , Jinap S. , Baharin B. S. , Bakar J.
Published: September 2002

A simple and rapid Fourier transform infrared (FTIR) spectroscopic method has been developed for the quantitative determination of malondialdehyde as secondary oxidation product in a palm olein system. The FTIR method was based on a sodium chloride transmission cell and utilised a partial least square statistical approach to derive a calibration model. The frequency region combinations that gave good calibration were 2900–2800, and 1800–1600 cm−1. The precision and accuracy, in the range 0–60 µmol malondialdehyde/kg oil, were comparable to those of the modified distillation method with a coefficient of determination (r2) of 0.9891 and standard error of calibration of 1.49. The calibration was cross‐validated and produced an r2 of 0.9786 and standard error of prediction of 2.136. The results showed that the FTIR method is versatile, efficient and accurate, and suitable for routine quality control analysis with the result obtainable in about 2 min from a sample of less than 2 mL. Copyright © 2002 John Wiley & Sons, Ltd.
Early second trimester prenatal diagnosis of Neu‐Laxova syndrome
Authors: Driggers R. W. , Isbister S. , McShane C. , Stone K. , Blakemore K.
Published: September 2002

Neu‐Laxova is a rare, uniformly lethal, autosomal recessive condition with characteristic limb posturing, facial dysmorphic features, and central nervous system abnormalities. Forty‐two cases of Neu‐Laxova syndrome have been reported, with only four of these diagnosed prenatally. Three of the four cases were diagnosed at or after 32 weeks' gestation. The fourth case was diagnosed at 22 weeks' gestation in a patient who was followed with serial ultrasound studies due to having a prior affected child. At 19 weeks' gestation, we present the earliest reported prenatal diagnosis of Neu‐Laxova syndrome in a primigravida with a non‐informative family history. Copyright © 2002 John Wiley & Sons, Ltd.
Prenatal diagnosis of a lethal form of Netherton syndrome by SPINK5 mutation analysis
Authors: Bitoun E. , Bodemer C. , Amiel J. , de Prost Y. , Stoll C. , Calvas P. , Hovnanian A.
Published: September 2002

Netherton syndrome (NS) is a severe autosomal recessive ichthyosis with no specific treatment or prenatal diagnosis available at present. The recent identification of SPINK5, which encodes a serine protease inhibitor, as the defective gene enables DNA‐based prenatal diagnosis to be carried out. Here we report the first direct molecular prenatal diagnosis of a lethal form due to a recurrent SPINK5 mutation in three consanguineous Turkish families. XmnI restriction enzyme digestion and DNA sequencing demonstrated that each deceased affected child was homozygous for mutation 153delT inherited from each parent. Analysis of fetal DNA from amniotic fluid cells in Family 1 and from a chorionic villus sampling in Family 3 showed that the fetus was heterozygous for 153delT in both cases. The pregnancies were carried to term and the newborns were unaffected. In Family 2, fetal DNA analysis from chorionic villus biopsy showed in a first pregnancy that the fetus was homozygous for 153delT. The pregnancy was terminated at 13 weeks and DNA analysis of fetal keratinocytes confirmed the prenatal prediction. In a second pregnancy in Family 2, fetal DNA analysis showed heterozygosity for 153delT, and the pregnancy was continued. Direct SPINK5 mutation analysis in families at risk for NS represents the first early, rapid and reliable method for prenatal diagnosis of this life‐threatening form of ichthyosis. Copyright © 2002 John Wiley & Sons, Ltd.
Usefulness of automated chromatography for rapid fetal blood analysis for second trimester prenatal diagnosis of β‐thalassemia
Authors: Wadia Mahrukh R. , Phanasgaokar Supriya P. , Nadkarni Anita H. , Surve Reema R. , Gorakshakar Ajit C. , B. Colah Roshan , Mohanty Dipika
Published: September 2002

Prenatal diagnosis of β‐thalassemia is now ideally done in the first trimester of pregnancy by chorionic villus tissue DNA analysis. Nevertheless, fetal blood analysis in the second trimester is required either when the mutation in both parents cannot be characterised or when the couple comes late for investigations. We evaluated the usefulness of analysis of fetal blood on the Biorad Variant Hemoglobin Testing System using the β‐thalassemia short programme in comparison with the conventional globin biosynthesis in 58 pregnancies. The β/α biosynthesis ratios in 13 homozygous fetuses ranged from 0 to 0.03 and the adult hemoglobin (HbA) levels by automated chromatography varied from 0% to 0.4%. The normal or heterozygous fetuses had β/α ratios of >0.04 and HbA levels ranging from 2.1% to 10.6%. In 17 fetuses we also correlated the β gene mutations with the predicted genotypes using automated high‐performance liquid chromatography (HPLC). Follow‐up of 18 unaffected fetuses using the Variant System at birth showed a significant increase in HbA levels. Copyright © 2002 John Wiley & Sons, Ltd.
Fetal, neonatal cord, and maternal plasma concentrations of angiotensin‐converting enzyme (ACE)
Authors: Walther Thomas , Faber Renaldo , Maul Björn , Schultheiss Heinz‐Peter , Siems Wolf‐E. , Stepan Holger
Published: September 2002

Objectives

Angiotensin‐converting enzyme (ACE), a component of the renin–angiotensin system (RAS), catalyses the degradation of angiotensin I to angiotensin II. It was the aim of the present study to measure ACE activity in human fetal blood and to determine its changes with advancing gestational age.

Methods

Fetal blood was sampled by cordocentesis from six control fetuses and six fetuses with Rh isoimmunisation. Cord blood was sampled from six preterm neonates, 15 neonates after spontaneous delivery at term and six neonates at term after caesarean section. In addition, maternal ACE values were determined. ACE activity was measured using the miniaturised fluorimetric method.

Results

In normal fetuses (13.31±1.41 nmol HL/min/ml) and fetuses with Rh isoimmunisation (13.08±2.00 nmol HL/min/ml) ACE activity was significantly higher than in corresponding maternal plasma (10.39±0.93 nmol HL/min/ml, p<0.05). Neonatal cord blood of preterm newborns (10.43±0.69 nmol HL/min/ml) and term newborns (8.99±0.49 nmol HL/min/ml) showed a significantly decreased ACE activity compared to the fetal controls.

Conclusion

We conclude that the high fetal ACE activity and the stringent regulation with advancing gestational age indicate the physiological importance of the enzyme during prenatal development. Copyright © 2002 John Wiley & Sons, Ltd.
Prenatal diagnosis of ventricular aneurysm: a report of two cases and a review
Authors: Pipitone Salvatore , Sperandeo Velio , Mongiovi Maurizio , Roberto Grillo , Centineo Giuseppe
Published: September 2002

Ventricular aneurysms have rarely been reported prenatally. Their prognosis is variable depending on factors such as early detection, their relative size in comparison to the ventricular cavity, growth on follow‐up, and signs of cardiac failure. In view of the fact that it may be useful to report on additional cases in order to make available further information on aetiology, prognosis and neonatal management, we hereby report on two cases of ventricular aneurysm with good mid‐term prognosis. One case of apical aneurysm of the left ventricle was associated with a muscular ventricular septal defect, the features of which are compatible with a fetal myocardial infarction and ventricular septal rupture in absence of coronary artery anomalies as demonstrated by catheterisation. Another case of sub‐tricuspidal aneurysm of the right ventricle associated with mitral prolapse appears to be a component of diffuse connective dysplasia. Despite the early gestational age at diagnosis, the large size of the aneurysm and the associated defect, both the infants were asymptomatic in infancy prompting a conservative management. Copyright © 2002 John Wiley & Sons, Ltd.
Womens' preference in Down syndrome screening
Authors: de Graaf Irene M. , Tijmstra Tjeerd , Bleker Otto P. , van Lith Jan M. M.
Published: September 2002

Objective

To determine the knowledge of pregnant women about prenatal tests, and what tests they would choose if offered. Also, the preference of pregnant women for second‐trimester or first‐trimester screening was assessed.

Patients and methods

Pregnant women receiving antenatal care in a decentralized primary care system (n=80), and pregnant women that were offered a prenatal diagnosis at the Academic Medical Centre (n=195), were asked to complete a questionnaire.

Results

The response rate was over 80%. Most women in both groups preferred a screening test for Down syndrome to be performed in the first trimester of pregnancy. A combination of nuchal translucency measurement and first‐trimester serum screening was the option of choice. The screening possibilities for Down syndrome were less well known to the women in the low‐risk group compared with the women in the high‐risk group. The offer of a prenatal screening test would have been declined by more than 30% of women at low risk for carrying a fetus with Down syndrome.

Conclusions

Our results show that women prefer screening for Down syndrome to be performed in the first trimester of pregnancy, using both serum and ultrasound tests. In women at low risk for Down syndrome the knowledge of prenatal screening methods was less, as well as the acceptance of prenatal screening being lower. Copyright © 2002 John Wiley & Sons, Ltd.
The effect of ethnic origin on nuchal translucency at 10–14 weeks of gestation
Authors: Chen Min , Hang Lam Yung , Hoi Yin Tang Mary , Peng Lee Chin , Yuen Sin Sai , Tang Rebecca , Soo Wong Hong , Fun Wong Sai
Published: September 2002

Introduction

Fetal nuchal translucency (NT) increases with gestation and is affected by fetal posture and fetal gender. A recent report suggested that there might also be ethnic differences. We investigated the effect of ethnic origin on NT in an Asian population.

Methods

NT was measured at 10–14 weeks. The measurements were converted into multiples of the median (MoM) for gestational day. The risk of Down syndrome was calculated by combining NT and maternal age. Cases affected by chromosomal and major structural abnormalities were excluded. NT measurements of different ethnic groups were compared.

Results

Between January 1997 and October 2001, 16 981 pregnancies with known ethnic origin and normal fetal outcome were analysed. Median NT MoM (95% CI) of the Filipinos was 1.07 (1.04–1.11). This was significantly higher than that of the Chinese, 1.01 (1.01–1.02); other Asians (Indians, Pakistanis and Nepalese), 0.96 (0.94–0.99), and Caucasians, 0.98 (0.93–1.06) (p<0.05, respectively; Mann–Whitney U‐test). An NT risk cut‐off of 1:180 would classify 5% of the Chinese, 4.6% of the Caucasians, 5.6% of the Filipinos and 4.2% of the other Asians as screen‐positive. There were no statistically significant differences between these screen‐positive rates (p>0.05, Chi‐square test).

Conclusion

Although there were statistically significant differences in NT measurements between different ethnic groups, it was clinically insignificant, as reflected by similar screen‐positive rates. Copyright © 2002 John Wiley & Sons, Ltd.
In utero sonographic diagnosis of a communicating enteric duplication cyst in a giant omphalocele
Authors: Tseng Jenn‐Jhy , Chou Min‐Min , Shih‐Chu Ho Esther
Published: September 2002

Enteric duplications are rare lesions, and relatively few cases have been diagnosed prenatally. We present, to our knowledge, the first case of an associated communicating ileal duplication cyst in a huge omphalocele diagnosed prenatally. The prenatal ultrasound findings revealed four features of the cystic lesion including peristaltic movements of the cystic wall, communication between the cyst and normal bowel lumen, intra‐cystic echogenic contents, and echogenic mesenteric tissue (fat) close to the cyst. These distinct characteristics helped us to make a firm in utero diagnosis. Copyright © 2001 John Wiley & Sons, Ltd.
Isolated mild fetal cerebral ventriculomegaly: a retrospective analysis of 26 cases
Authors: Mercier A. , Eurin D. , Mercier P. Y. , Verspyck E. , Marpeau L. , Marret S.
Published: September 2002

We retrospectively studied 26 fetuses with isolated mild cerebral ventriculomegaly diagnosed between 1992 and 1998 and defined by a lateral ventricular atrial diameter of 10–15 mm without any other cerebral anomaly. Our objectives were to determine maternal risk factors, to evaluate complementary investigations, to assess developmental prognosis and to propose possible management. During pregnancy 10/26 patients had regressive ventriculomegalies, ten remained borderline at birth and six were confirmed postnatally. No maternal risk factors were identified. Prenatal investigations were carried out in 69% of cases but in only a few cases supplied any information. Postnatal examinations revealed one case of Down syndrome and one of porencephaly. Four children were lost to follow‐up. In the 22 other cases, four had developmental delay. Early and unexplained mild ventriculomegaly appears to have a good prognosis. If ventriculomegaly is persistent, prenatal management should be carried out to investigate chromosomal abnormalities, viral infection, and fetal cerebral parenchymal damage. A long postnatal clinical follow‐up is required. Copyright © 2001 John Wiley & Sons, Ltd.
Restrictive dermopathy and fetal behaviour
Authors: Mulder E. J. H. , Beemer F. A. , Stoutenbeek Ph.
Published: September 2002

We report three siblings from consecutive pregnancies affected with restrictive dermopathy (RD). During the second pregnancy, fetal behavioural development and growth were studied extensively using ultrasound at 1–4 week intervals. Dramatic and sudden changes occurred in fetal body movements and growth but not until the end of the second trimester of pregnancy. Prominent at that time were prolonged periods of fetal quiescence and very low heart rate variability, together with abnormally executed body movements of short duration. Retarded femoral development and jerky abrupt fetal body movements (abnormal movement quality) were already present in the early second trimester of pregnancy. Facial anomalies emerged despite the presence of fetal mouth movements. The clinical features of RD were only partly explained by present knowledge of skin development and the fetal akinesia deformation sequence hypothesis. Quantitative assessment of fetal movements proved to be a poor early marker for antenatal diagnosis of this disorder. Copyright © 2001 John Wiley & Sons, Ltd.
Rapid and radical amniodrainage in the treatment of severe twin–twin transfusion syndrome†
Authors: Jauniaux Eric , Holmes Anna , Hyett Jon , Yates Robert , Rodeck Charles
Published: September 2002

We have evaluated the role of a rapid and radical method of amniodrainage in the treatment of severe twin–twin transfusion. The outcome of 15 patients with severe twin–twin transfusion for which a amniodrainage was performed by means of a vacuum bottle system was compared with the outcome of 15 patients with a similar condition, matched for gestational age at the time of the initial procedure and drained using a standard procedure. In the study group the amniodrainage ended when no amniotic fluid could be aspirated, whereas the women in the standard group were drained with a syringe system and the fluid was removed until the deepest amniotic fluid pool was <8 cm. At the initial procedure, the mean volume of amniotic fluid drained was significantly (p<0.05) higher (3252 vs 2153 ml) and the length of the procedure significantly (p<0.001) shorter (21 vs 41 min) in the study group than in the standard group. The mean post‐procedure amniotic fluid index was significantly (p<0.001) smaller (2.9 vs 7.7 cm) after radical amniodrainage than after the standard amniodrainage. The mean number of procedures was significantly (p<0.001) lower (1.5 vs 5.6) in the study group compared to the standard group. In the study group the mean placental thickness increased significantly (p<0.001) from 9 mm before the procedure to 49 mm after, and the overall perinatal survival rate was 80% and the proportion of pregnancies with at least one survivor was 93%. The present data indicate that early, rapid and radical amniodrainage is an effective and low‐cost therapy for severe twin–twin transfusion syndrome. Compared to the standard amniodrainage technique it also appears to reduce the need for multiple procedures. Copyright © 2001 John Wiley & Sons, Ltd.
Prenatal diagnosis in three cases of iniencephaly with unusual postmortem findings
Authors: Balcı Sevim , Aypar Ebru , Altınok Gülçin , Boduroğlu Koray , Beksaç M. Sinan
Published: September 2002

Iniencephaly is a rare and lethal congenital malformation of the neural tube characterized by occipital bone defect, cervical dysraphism, fixed retroflexion of the fetal head and severe lordosis of the cervicothoracic spine. The etiology is unknown. Prenatally diagnosed cases of iniencephaly are rare because careful and early ultrasonographic evaluation is necessary. We present three cases of iniencephaly prenatally diagnosed by sonography at 20–22 weeks' gestation in which therapeutic abortion was induced. The sonographic findings were compatible with the postmortem findings. The present cases of iniencephaly were found to carry unusual associated malformations such as two lobes in the right lung and chorangiosis of the placenta. Only hypoplastic lungs have been reported by previous authors. We also studied the 677C→T mutation on the methylenetetrahydrofolate reductase gene in the parents in one of the present cases. The mother was found to be heterozygous for the 677CT polymorphism. Copyright © 2001 John Wiley & Sons, Ltd.
Complete karyotype discrepancy between placental and fetal cells in a case of ring chromosome 18
Authors: Fischer Wolfgang , Dermitzel Anette , Osmers Rüdiger , Pruggmayer Michael
Published: September 2002

A case of complete karyotype discrepancy between cultured chorionic villi and amniotic in addition to fetal cells is reported. Ring chromosome 18 and monosomy 18 mosaicism was detected after amniocentesis. The pregnancy was terminated in the 23rd gestational week. Cytogenetic analysis of cultured umbilical cord tissue after termination confirmed the finding of ring chromosome 18/monosomy 18 mosaicism. In cultured umbilical blood lymphocytes monosomic cells 45,‐18 were not detected and the karyotype was 46,XY,r(18). In contrast, short‐term and long‐term cultured chorionic villi showed a normal male karyotype of 46,XY. Ultrasonographic examination revealed amniotic band syndrome and scoliosis in the caudal region of the spine. Copyright © 2001 John Wiley & Sons, Ltd.
Oral corticosteroids produced excellent healing in a diabetic foot ulcer: a case of pyoderma gangrenosum of the foot
Authors: Norris Andrea , Teo Hong Gip , Stephens WP , Muston H
Published: September 2002

A case of pyoderma gangrenosum is described, affecting the foot of a diabetic patient. Initial appearances were suggestive of bacterial secondary infection complicating athlete's foot. Within three days of oral corticosteroid therapy the lesion had virtually healed. The diagnosis of pyoderma gangrenosum should be considered in diabetic patients with atypical ulcerative skin lesions, particularly those sterile on culture. Copyright © 2001 John Wiley & Sons, Ltd.
Effects of a monetary incentive on primary care prescribing in Ireland: changes in prescribing patterns in one health board 1990–1995
Authors: Walley T. , Murphy M. , Codd M. , Johnston Z. , Quirke T.
Published: September 2002

Background

In an attempt to curb the rapidly rising costs of primary care prescribing in Ireland, the government introduced a financial incentive scheme in 1993, to encourage general practitioners to restrain their prescribing.

Purpose

To investigate the effects of a financial incentive scheme on GP prescribing in Ireland on prescribing costs and volume, and on some specific therapeutic areas.

Methods

Prescribing for 3 years before (1990–1992) and 3 years (1993–1995) after the introduction of incentives, based on a defined cohort of 233 general practitioners in the area of one health board. GPs were divided into tertiles based on their performance against their prescribing budgets into ‘savers’ (generally underspent and received incentive payments), modest overspenders and large overspenders.

Results

Savers were always lower cost prescribers than the other groups. They contained their rate and costs of prescribing in contrast to the other groups, e.g. percentage rise in prescribing costs in the year after the introduction of the scheme − 7.9%, + 1.2% and + 7.3% respectively, (P< 0.05) for savers, modest overspenders and large overspenders respectively. This effect was short lived however and was gone by the third year of the study.

Conclusions

The financial incentives had a marked effect on prescribing volume and cost on some practices who could achieve targets and hence incentive payments. The incentives had little effect on high spending practices. Such incentive schemes need careful evaluation if they are not to become perverse to the good health of patients. Copyright © 2000 John Wiley & Sons, Ltd.