bluuebunny/crossref_metadata_2025 huggingface dataset:
Nematic Anisotropic Liquid‐Crystal Gels—Self‐Assembled Nanocomposites with High Electromechanical Response
Authors: Huang C. , Zhang Q.M. , Jákli A.
Published: July 2003

The uniqueness of liquid crystals (LCs) lies in the large anisotropies of their properties, which can be utilized to generate high electromechanical responses. In a properly oriented LC polymer system, an external electric field can induce reorientation of the mesogenic units possessing a dielectric anisotropy, which, when coupled with the shape anisotropy of the mesogenic units, can in turn produce large mechanical strain. Anisotropic LC gels, which can be obtained by in‐situ photopolymerization of the reactive LC molecules in the presence of non‐reactive LC molecules in an oriented state, are an example of such liquid‐crystal polymer systems. It is shown here that a homeotropically aligned LC gel in its nematic phase exhibits high electrically induced strain (> 2 %) with an elastic modulus of 100 MPa and a high electromechanical conversion efficiency (75 %) under an electric field of 25 MV/m. These anisotropic LC polymeric materials could provide a technologically compatible system for such applications as artificial muscles and as microelectromechanical devices.
Micro‐Nanostructured Interfaces Fabricated by the Use of Inorganic Block Copolymer Micellar Monolayers as Negative Resist for Electron‐Beam Lithography
Authors: Glass R. , Arnold M. , Blümmel J. , Küller A. , Möller M. , Spatz J.P.
Published: July 2003

This paper introduces an approach where the match of two different length scales, i.e., pattern from self‐assembly of block copolymer micelles (< 100 nm) and electron‐beam (e‐beam) writing (> 50 nm), allow the grouping of nanometer‐sized gold clusters in very small numbers in even aperiodic pattern and separation of these groups at length scales that are not accessible by pure self‐assembly. Thus, we could demonstrate the grouping of Au nanoclusters in different geometries such as squares, rings, or spheres.
Discovery and Optimization of New ZnO‐Based Phosphors Using a Combinatorial Method
Authors: Mordkovich V.Z. , Hayashi H. , Haemori M. , Fukumura T. , Kawasaki M.
Published: July 2003

The combinatorial method, which was exclusively employed for the drug discovery until recently, has invaded the field of inorganic materials and is becoming a key technology in materials science today. Phosphors, with their diversity of possible mechanisms of luminescence, represent a typical example of a field where the combinatorial approach promises to be especially fruitful. Here, we present the results of systematic combinatorial exploration of different binary and ternary ZnO:dopant systems, which resulted in identification of bright luminescence in ZnO:(Y,Eu), ZnO:V, ZnO:W, and ZnO:(W,Mg) systems. Careful “zooming in”, i.e., fabrication and screening of more detailed libraries near the identified promising compositions, allowed us to find optimum phosphor compositions for the above‐mentioned systems. The efficiency of the new phosphors in low‐voltage cathodoluminescence is high and promises their prospective use in advanced flat panel display and lighting applications.
Fabrication and Characterization of Stable Ultrathin Film Micropatterns Containing CdS Nanoparticles
Authors: Lu C.H. , Wu N.Z. , Wei F. , Zhao X.S. , Jiao X.M. , Xu J. , Luo C.Q. , Cao W.X.
Published: July 2003

Stable, ultrathin micropatterns containing CdS nanoparticles (CdS‐NPs) were fabricated in a two‐step process. In the first step, a precursor film was built‐up by the layer‐by‐layer electrostatic self‐assembly of photosensitive nitro‐diazoresin and mercaptoacetic acid capped CdS nanoparticles. In the second step, the film was selectively exposed to UV light through a photomask and developed in an aqueous solution of sodium dodecylsulfate (SDS). The formation of covalently linked micropatterns was based on the different solubilities of the irradiated and non‐irradiated parts of the film in the developer. Namely, the irradiated regions were cross‐linked and insoluble, whereas the non‐irradiated regions, linked with ionic bonds, were removed by the SDS solution. The resultant patterns were systematically characterized with atomic force microscopy, field emission scanning electron microscopy, optical microscopy, and X‐ray photoelectron spectroscopy.
Perfluoroalkanoate‐Substituted PEDOT for Electrochromic Device Applications
Authors: Schwendeman I. , Gaupp C.L. , Hancock J.M. , Groenendaal L. , Reynolds J.R.
Published: July 2003

The recent emergence of organic electrochromics on both the scientific and industrial levels has expedited the synthesis of new materials with varied electrochemical and optical properties. The structural versatility and broad usage of poly(3,4‐ethylenedioxythiophene) (PEDOT) has stimulated many research groups to focus on the potential of PEDOT derivatives. Here we report the first synthesis of pentadecafluoro‐octanoic acid 2,3‐dihydro‐thieno(3,4‐b)(1,4)dioxin‐2‐ylmethylester (EDOT‐F), along with its electrochemical polymerization, characterization, and incorporation into electrochromic devices (ECDs). PEDOT‐F is a cathodically coloring polymer that exhibits sub‐second switching time between a dark‐blue neutral state and a transmissive sky‐blue oxidized state, and expresses a 63 % change for both transmittance at λmax and colorimetrically determined luminance. Hexafluorophosphate‐doped free‐standing films of PEDOT‐F possess conductivities of up to 65 S cm–1. Variable transmittance ECDs constructed with PEDOT‐F and poly[3,6‐bis(2‐(3,4‐ethylenedioxythienyl))‐N‐methylcarbazole] (PBEDOT‐NMeCz) exhibit an optical contrast of 60 % at λmax (580 nm) and an overall luminance change of 60 %. Indicating the hydrophobicity of this polymer, doped PEDOT‐F exhibits a water contact angle of 110°, significantly higher than the 30° exhibited for the doped PEDOT parent.
Nanoweb Formation: 2D Self‐Assembly of Semiconductor Gallium Oxide Nanowires/Nanotubes
Authors: Graham U.M. , Sharma S. , Sunkara M.K. , Davis B.H.
Published: July 2003

This paper reports a method to produce networks of crystalline gallium oxide comprised of one‐dimensional (1D) nanostructures. Because of the unique arrangement of wires, these crystalline networks are termed as ‘nanowebs’. Nanowebs are of great technological interest since they contain wire densities of the order of 109 cm–2. A possible mechanism for the fast self‐assembly of crystalline metal oxide nanowires involves multiple nucleation and coalescence via oxidation–reduction reactions at the molecular level. The preferential growth of nanowires parallel to the substrate enabled them to coalesce into regular polygonal networks. The individual segments of the polygonal network consist of both nanowires and nanotubules of β‐gallium oxide. Individual wire properties contribute to a nanoweb’s overall capacity and the implications for devices based on nanowebs are expected to be enormous.
Porous Materials and Supercritical Fluids
Authors: Cooper A.I.
Published: July 2003

Porous materials are used in a wide variety of applications, including catalysis, chemical separation, and tissue engineering. The synthesis and processing of these materials is frequently solvent intensive. In addition to reducing organic solvent emissions, supercritical fluids offer a number of specific physical, chemical, and toxicological advantages as alternative solvents for the production of functional porous materials. The figure shows an electron image of a porous polyacrylate produced by the templating of a concentrated CO2‐in‐water emulsion—a process that would otherwise be highly solvent intensive.
Measuring the Efficiency of Organic Light‐Emitting Devices
Authors: Forrest S.R. , Bradley D.D.C. , Thompson M.E.
Published: July 2003

As organic light‐emitting devices emerge from the stage of being a research curiosity to that of becoming a practical appliance with important commercial applications, the need for a coherent and accurate standard technique for measuring device efficiencies becomes increasingly important. By following the methods described in this contribution, measurements made in disparate laboratories testing a wide range of materials and device structures should agree, to within small experimental errors, on the properties of the subject devices.
Up‐conversion Luminescence in Dye‐Doped Crystals of Potassium Hydrogen Phthalate
Authors: Benedict J.B. , Wallace P.M. , Reid P.J. , Jang S.‐H. , Kahr B.
Published: July 2003

Optically nonlinear single crystals of potassium hydrogen phthalate were grown in the presence of a variety of laser dyes. Up‐conversion fluorescence (as shown in the Figure) in the visible part of the spectrum was observed as a result of two excitation mechanisms involving trapped, oriented luminophores: two‐photon absorption in general orientations, and absorption of the second harmonic of the fundamental beam at 800 nm, when aligned with the phase‐matching direction.
Fabrication and Characteristics of 2‐Acrylamido‐2‐methyl‐1‐propanesulfonic Acid‐Doped Polyaniline Hollow Fibers
Authors: Yang J. , Burkinshaw S.M. , Zhou J. , Monkman A.P. , Brown P.J.
Published: July 2003

Polyaniline:2‐acrylamido‐2‐methyl‐1‐propanesulfonic acid has been wet‐spun to yield hollow fibers using dichloroacetic acid as the solvent. The fibers have excellent circular cross‐sections and good surface morphology, as can be seen from the Figure. The permeability of the fibers, as suitable for gas separation, has been assessed.
Near‐Infrared Electroluminescence from Lanthanide Tetraphenylporphyrin:Polystyrene Blends
Authors: Kang T.‐S. , Harrison B.S. , Foley T.J. , Knefely A.S. , Boncella J.M. , Reynolds J.R. , Schanze K.S.
Published: July 2003

Using a simple non‐conjugated polymer host, blends with tetraphenylporphyrin complexes of ytterbium [Yb(TPP)L] have been used to construct near‐infrared‐emitting diodes in which the Yb(TPP)L serves as both the emitter and charge‐transport medium. The Figure shows the structure of Ln(TPP)L(OEt), and a simplified mechanism of light‐emitting diode operation.
Fabrication of Reversely Tapered Three‐Dimensional Structures and Their Application to Organic Light‐Emitting Diodes
Authors: Rhee J. , Park J. , Kwon S. , Yoon H. , Lee H.H.
Published: July 2003

Cathode separators typically used for patterning metal cathodes of organic light‐emitting diodes (OLEDs)—see Figure—can be fabricated using a lithography‐based technique that allows the construction of reversely tapered 3D structures in one single molding step. The physics involved in making the fabrication of such 3D structures possible is outlined and the efficacy of the separator thus fabricated is demonstrated with an OLED.
Direction‐Selective and Length‐Tunable In‐Plane Growth of Carbon Nanotubes
Authors: Cao A. , Baskaran R. , Frederick M.J. , Turner K. , Ajayan P.M. , Ramanath G.
Published: July 2003

Chemical vapor deposition on selectively masked SiO2 patterns has been used to obtain controlled placement and exclusive in‐plane growth of length‐ and direction‐tunable carbon nanotubes (see Figure and inside cover). Nanotube bridges interconnecting SiO2 patterns are fabricated, and their electrical characteristics are demonstrated. This approach holds promise for manufacturing large‐scale microelectronic systems integrated with nanotube–electrode units.
Effects of Annealing on the Properties of Molecular Thin Film Heterostructures
Authors: Heutz S. , Salvan G. , Jones T.S. , Zahn D.R.T.
Published: July 2003

The effects of post‐growth annealing on the structure, morphology, and spectroscopic properties of molecular double‐layer heterostructures containing perylene‐3,4,9,10‐tetracarboxylic dianhydride (PTCDA) and metal‐free phthalocyanine (H2Pc) have been investigated. The templated structure adopted by H2Pc on PTCDA protects the underlying PTCDA layer from sublimation, unless the H2Pc thickness is < 20 nm (see Figure).
Synthesis of Aligned Carbon Nanotubes with Double Coaxial Structure of Nitrogen‐Doped and Undoped Multiwalls
Authors: Xu W. , Kyotani T. , Pradhan B.K. , Nakajima T. , Tomita A.
Published: July 2003

Aligned carbon nanotubes with a double coaxial structure of nitrogen‐doped and undoped multiwalls are fabricated using an aluminum anodic oxide film as a template. A bundle of nanotubes is shown in the Figure. The new technique opens up a novel route for the synthesis of carbon nanotubes with coaxial heterojunctions by stacking layers with different heteroatom‐doping.
A New Approach to Organic Solvent Detection: High‐Reflectivity Bragg Reflectors Based on a Gold Nanoparticle/Teflon‐like Composite Material
Authors: Convertino A. , Capobianchi A. , Valentini A. , Cirillo E.N.M.
Published: July 2003

A new sensing element for organic solvents based on a polymeric distributed Bragg reflector (DBR) is presented. The periodic stack consists of alternating Teflon‐like and gold nanoparticle/Teflon‐like layers, and shows high reflectivity in the optical telecommunications spectral range. Sensing properties are due to the peculiar absorbing behavior of composite layers, which swell in the presence of organic vapors, causing DBR periodicity change and consequently the high reflectivity window shift (see Figure).
The Formation of Well‐Defined Hollow Silica Spheres with Multilamellar Shell Structure
Authors: Sun Q. , Kooyman P.J. , Grossmann J.G. , Bomans P.H.H. , Frederik P.M. , Magusin P.C.M.M. , Beelen T.P.M. , van Santen R.A. , Sommerdijk N.A.J.M.
Published: July 2003

Hollow mesoporous silica spheres that are highly defined in shape and size (see Figure) are prepared using a poly(ethylene oxide)–poly(propylene oxide)–poly(ethylene oxide) [PEO–PPO–PEO] block copolymer based emulsion as the template, and sodium silicate as the silica source. The wall structure of the particles depends on the reaction temperature and can be monitored using small‐angle X‐ray scattering, solid‐state NMR spectroscopy, and cryo‐transmission electron microscopy.
A Simple Route to the Synthesis of Pr2O3 High‐k Thin Films
Authors: Lo Nigro R. , Toro R.G. , Malandrino G. , Raineri V. , Fragalà I.L.
Published: July 2003

High‐quality Pr2O3 high‐k thin films with very promising electrical properties have been prepared by metal–organic chemical vapor deposition on Si(100) substrates. The most critical factor for selective and reproducible Pr2O3 film formation is the oxygen partial pressure in the reaction chamber. X‐ray (see Figure) and transmission electron microscopy diffraction patterns show that the oxide layer grows with a hexagonal random structure.
Fabrication of Large‐Area Periodic Nanopillar Arrays for Nanoimprint Lithography Using Polymer Colloid Masks
Authors: Kuo C.‐W. , Shiu J.‐Y. , Cho Y.‐H. , Chen P.
Published: July 2003

Large‐area, well‐ordered, periodic nanopillar arrays (see Figure) can be fabricated using a combination of double‐layer nanosphere lithography and reactive ion etching. The nanopillar arrays fabricated by this method can, in turn, be used as the stamps for nanoimprint lithography. The results presented indicate that this approach can be used to produce large‐area sub‐50 nm periodic nanostructures.
Conductive Core–Shell Particles: An Approach to Self‐Assembled Mesoscopic Wires
Authors: Kaltenpoth G. , Himmelhaus M. , Slansky L. , Caruso F. , Grunze M.
Published: July 2003

Conductive core–shell particles consisting of a dielectric core and a metallic shell were prepared using layer‐by‐layer assembly and electroless plating. Conductivity was studied using X‐ray photoelectron spectroscopy and UV‐vis spectroscopy as a function of the preparation protocol. Routines for the controlled self‐assembly of these particles into continuous lines (see Figure and cover) were investigated to explore their applicability in self‐assembled mesoscopic wiring.
Novel Glassy Nematic Liquid Crystals for Non‐destructive Rewritable Optical Memory and Photonic Switching
Authors: Chen S.H. , Chen H.M.P. , Geng Y. , Jacobs S.D. , Marshall K.L. , Blanton T.N.
Published: July 2003

Dithienylethene‐containing glassy nematic liquid crystals (see Figure) have been synthesized, in which the dithienylethene core’s electronic transition moment is uniaxially aligned. Large changes in refractive index and optical birefringence could be induced in the solid state by photochemical means. Applications in non‐destructive rewritable optical memory and high‐speed photonic switches are envisaged.
Fabrication of Highly Conductive 12CaO·7Al2O3 Thin Films Encaging Hydride Ions by Proton Implantation
Authors: Miyakawa M. , Hayashi K. , Hirano M. , Toda Y. , Kamiya T. , Hosono H.
Published: July 2003

Thin films of a new transparent oxide semiconductor 12CaO·7Al2O3 consisting of subnanometer‐sized cages (see Figure inset) have been fabricated, and their light‐induced insulator–conductor conversion is described. Proton implantation at a fluence of 1 × 1018 cm–2 followed by UV‐light irradiation increases the electrical conductivity by more than eleven orders of magnitude to the largest value ∼ 10 S cm–1 (see Figure). The conducting state is erasable by heating.
Tetramethylpentacene: Remarkable Absence of Steric Effect on Field Effect Mobility
Authors: Meng H. , Bendikov M. , Mitchell G. , Helgeson R. , Wudl F. , Bao Z. , Siegrist T. , Kloc C. , Chen C.‐H.
Published: July 2003

A new pentacene derivative, 2,3,9,10‐tetramethyl‐pentacene (Me4PENT), has been synthesized, characterized, and tested in a field‐effect transistor (FET) device (see Figure). A bottom‐contact‐mode FET device fabricated with Me4PENT was shown to exhibit a high charge‐transport mobility of 0.31 cm2 V–1 s–1 when fabricated at a deposition substrate temperature of 85 °C.
Growth of Densely Packed Gold Nanoparticles on Graphite Using Molecular Templates
Authors: Guo Q. , Fallon P. , Yin J. , Palmer R.E. , Bampos N. , Sanders J.K.M.
Published: July 2003

The growth kinetics of deposited gold atoms on the surface of highly oriented pyrolytic graphite can be controlled by modification of the graphite surface by a single layer of zinc porphyrin trimer molecules. Densely packed nanocluster films (see Figure (200 nm × 200 nm)) result, rather than the open, fractal structure produced on the bare graphite surface. No permanent defects are produced in the substrate surface and the molecules can be removed following metal deposition.
Immobilized Polydiacetylene Vesicles on Solid Substrates for Use as Chemosensors
Authors: Kim J.‐M. , Ji E.‐K. , Woo S.M. , Lee H. , Ahn D.J.
Published: July 2003

Polydiacetylene‐based chemosensors are prepared by assembling liposomes of diacetylene monomers with terminal amine groups on an aldehyde‐modified glass substrate, and polymerizing them by irradiation with UV light. Incubation of the immobilized film sensor in a poly(acrylic acid) solution results in a color change from the original blue (solid line in Figure) to the red phase (broken line).
A New Method for the Synthesis of Highly Dispersive and Catalytically Active Platinum Nanoparticles Confined in Mesoporous Zirconia
Authors: Chen H.‐R. , Shi J.‐L. , Li Y.‐S. , Yan J.‐N. , Hua Z.‐L. , Chen H.‐G. , Yan D.‐S.
Published: July 2003

Pure metallic platinum nanocrystallites with uniform diameter, confined in the pore channels of mesoporous zirconia, have been synthesized by a new ion‐ exchange reaction followed by in‐situ reduction. Such a nanostructured platinum–zirconia mesoporous composite material is demonstrated to be an efficient catalyst for the oxidation of CO. Incorporation of ceria into the zirconia walls is shown to lead to a material with promise as a high‐performance exhaust‐conversion catalyst with immediate activation of the catalyst on engine start‐up.
Life insurance and breast cancer risk assessment: Adverse selection, genetic testing decisions, and discrimination
Authors: Armstrong Katrina , Weber Barbara , FitzGerald Genevieve , Hershey John C. , Pauly Mark V. , Lemaire Jean , Subramanian Krupa , Asch David A.
Published: June 2003

Life insurance industry access to genetic information is controversial. Consumer groups argue that access will increase discrimination in life insurance premiums and discourage individuals from undergoing genetic testing that may provide health benefits. Conversely, life insurers argue that without access to risk information available to individuals, they face substantial financial risk from adverse selection. Given this controversy, we conducted a retrospective cohort study to evaluate the impact of breast cancer risk information on life insurance purchasing, the impact of concerns about life insurance discrimination on use of BRCA1/2 testing, and the incidence of life insurance discrimination following participation in breast cancer risk assessment and BRCA1/2 testing. Study participants were 636 women who participated in genetic counseling and/or genetic testing at a University based clinic offering breast cancer risk assessment, genetic counseling, and BRCA1/2 testing between January 1995 and May 2000. Twenty‐seven women (4%) had increased and six (1%) had decreased their life insurance since participation in breast cancer risk assessment. The decision to increase life insurance coverage was associated with predicted breast cancer risk (adjusted OR 1.03 for each 1% absolute increase in risk, 95% CI 1.01–1.10) and being found to carry a mutation in BRCA1/2 (OR 5.10, 95% CI 1.90–13.66). Concern about life insurance discrimination was inversely associated with the decision to undergo BRCA1/2 testing (RR 0.67, 95% CI 0.52–0.85). No respondent reported having life insurance denied or canceled. In this cohort of women, these results indicate that information about increased breast cancer risk is associated with increase in life insurance purchasing, raising the possibility of adverse selection. Although fear of insurance discrimination is associated with the decision not to undergo BRCA1/2 testing, there was no evidence of actual insurance discrimination from BRCA1/2 testing. © 2003 Wiley‐Liss, Inc.
A new syndrome of symphalangism, multiple frenula, postaxial polydactyly, dysplastic ears, dental anomalies, and exclusion of NOG and GDF5
Authors: Kantaputra Piranit N. , Pongprot Yupada , Praditsap Oranud , Pho‐iam Theeraphong , Limwongse Chanin
Published: June 2003

A Thai girl with a unique combination of limb and craniofacial anomalies is reported. Manifestations include blepharoptosis; prominent nose; hypodontia; multiple, hyperplastic frenula; and dysplastic ears. Limb anomalies include short stature, postaxial polydactyly of both hands and the left foot, proximal and distal symphalangism of fingers, and congenital absence of the distal phalanges of toes 2–5. Mutation analyses of NOG and GDF5, the genes responsible for symphalangism‐related syndromes, were negative. © 2003 Wiley‐Liss, Inc.
Complete androgen insensitivity syndrome due to X chromosome inversion: A clinical report
Authors: Xu Weizhen , Robert Claudia , Thornton Paul S. , Spinner Nancy B.
Published: June 2003

We have studied a patient with complete androgen insensitivity syndrome (CAIS) and a 46, inv(X),Y karyotype. The patient's mother and maternal aunt also carry the inverted X, and the mother is phenotypically normal, with a 46, inv(X),X karyotype, while a maternal aunt has CAIS with a 46,inv(X),Y karyotype. Molecular cytogenetic studies demonstrate that one of the X inversion breakpoints occurs within Xq11.2–12, which is the locus for the androgen receptor. FISH analysis demonstrated that a BAC clone containing the androgen receptor gene was disrupted by the inversion. We therefore hypothesize that disruption of the androgen receptor gene causes CAIS in this patient. This is the first report of CAIS caused by a chromosome inversion. © 2003 Wiley‐Liss, Inc.
Factors affecting performance of prenatal genetic testing by Israeli Jewish women
Authors: Sher Carron , Romano‐Zelekha Orly , Green Manfred S. , Shohat Tamy
Published: June 2003

The number of prenatal genetic tests that are being offered to women is constantly increasing. However, there is little national data as to who is performing the tests and the reasons for doing or not doing so. This study evaluated the proportion of Jewish women in Israel who perform the various prenatal genetic tests and the factors affecting the performance of these tests. It was found that 60.9% of the women performed the triple test, 50.8% of women older than 35 years performed amniocentesis, while 63.3 and 24.3% of women performed Tay‐Sachs and fragile‐X carrier testing respectively. Ninety‐six percent of the secular women compared to only 6.7% of the ultrareligious women performed the triple test. It was also found that94.4% of the secular women, 36.4% of the religious, and none of the ultrareligious women older than 35 years performed amniocentesis. In the stepwise regression analysis, being secular, having a higher income, fewer children, and being of Ashkenazi origin remained significant factors in determining performance of Tay‐Sachs carrier testing. As regards fragile‐X carrier testing, being secular, having fewer than four children, and having a higher income and a supplementary medical insurance remained significant factors. The main reason reported by the women for not performing amniocentesis or the triple test was for religious or moral grounds (53.3 and 67% respectively). The main reason given for not performing Tay‐Sachs or fragile‐X testing was that they were not referred for the tests (76 and 82% respectively). Consideration should be given to providing first trimester prenatal diagnosis to the ultrareligious group, including state subsidized fragile‐X testing and educating the primary care givers about the importance of prenatal genetic testing. The information from the present study is vital for the planning of an equitable prenatal genetic service and provides guidelines for the implementation of such services in other countries. © 2003 Wiley‐Liss, Inc.
Visual–spatial performance deficits in children with neurofibromatosis type‐1
Authors: Schrimsher Gregory W. , Billingsley Rebecca L. , Slopis John M. , Moore Bartlett D.
Published: June 2003

Neurofibromatosis type‐1 (NF1) is a common genetic disorder associated with a variety of medical complications, cognitive impairments, and behavioral problems including a high incidence of Attention Deficit Hyperactivity Disorder (ADHD). The current study examined the hypotheses that deficits in visual–spatial/motor abilities enable one to discriminate and classify children with NF1 (n = 101) compared to control children (n = 37), beyond effects secondary to parent reported ADHD symptomology. Discriminant analysis showed a multivariate combination of visual–spatial/motor ability tests (Judgment of Line Orientation, Block Design subtest of the WISC‐III, Recognition–Discrimination Test, Beery Visual–Motor Integration Test) to be a significant predictor of NF1 diagnostic status (P = 0.0000004; canonical R2 = 0.2306). A significantly greater degree of ADHD behavior was found in the NF1 group, and a discriminant analysis using ADHD residualized visual–spatial motor scores indicated that the combination of tests continued to be a significant predictor of group membership after the level of ADHD behavior was controlled (P = 0.00002 and a canonical R2 = 0.1818). This combination of tests proved to be a strong discriminator of NF1. It correctly identified 90% of individuals with the diagnosis, and may be useful to educators to provide assistance and alternatives to minimize the impact of learning problems in those with either known or suspected NF1. © 2003 Wiley‐Liss, Inc.
Heat shock protein 27 gene: Chromosomal and molecular location and relationship to Williams syndrome
Authors: Stock A. Dean , Spallone Patricia A. , Dennis Thomas R. , Netski Dale , Morris Colleen A. , Mervis Carolyn B. , Hobart Holly H.
Published: June 2003

Heat shock protein 27 (HSP27) is one of a number of actin‐binding proteins that regulate actin polymerization. Three related HSP27 sequences had previously been mapped to chromosomes 3, 9, and X. We have used fluorescent in‐situ hybridization (FISH) to correct and refine the map position of the transcribed HSP27 gene (locus HSPB1) to chromosome 7q11.23. This band also contains the site of the deletion associated with Williams syndrome (WS). To define the relationship between HSP27 and the WS deletion, we used two‐color FISH on previously G‐banded and photographed metaphase chromosomes from WS cell‐lines and peripheral blood. Six WS patients with longer deletions that extend telomeric to the classical WS deletion region were analyzed for deletion length using HSP27, cosmids generated from P193O22 (cos11) and B350L10 (cos64 and 82), B350L10, B161A02, and B363M4. The BAC 363M4 was selected from the Washington University database and contains HSP27. Our results indicated that HSP27 was deleted in three patients and that HSP27 is telomeric to cos11, cos64, cos82, and B350L10. B363M4 was demonstrated to overlap the telomeric end of B161A02 and HSP27 may be contained partially within the telomeric end of B161A02. The possible role of HSP27 in the cognitive features of WS is discussed. © 2003 Wiley‐Liss, Inc.
Bowen–Conradi syndrome: A clinical and genetic study
Authors: Lowry R.B. , Innes A.M. , Bernier F.P. , McLeod D.R. , Greenberg C.R. , Chudley A.E. , Chodirker B. , Marles S.L. , Crumley M.J. , Loredo‐Osti J.C. , Morgan K. , Fujiwara T.M.
Published: June 2003

The purpose of the study was to delineate the anomalies and the natural life history of persons with the Bowen–Conradi syndrome [Bowen and Conradi 1976: Birth Defects: Orig Artic Ser XII(6):101–108]. We ascertained 39 cases and personally examined almost all. For those who were not seen, their clinical record were scrutinized. Pedigree analysis of all 39 was done and kinship coefficients computed. The birth prevalence was estimated to be 1/355 live births. © 2003 Wiley‐Liss, Inc.
Distal monosomy 18p/distal trisomy 20p—A recognizable facial phenotype?
Authors: Wieczorek Dagmar , Bartsch Oliver , Gillessen‐Kaesbach Gabriele
Published: June 2003

We describe an 8.5‐year‐old boy with facial dysmorphism consisting of a round and flat face, telecanthus, periorbital fullness, short nose, downturned corners of the mouth, and micrognathia. In addition, profound mental retardation, tetralogy of Fallot, and renal dysplasia were present. Tentative clinical diagnoses during the 6‐year follow‐up included Down, Hennekam, and Noonan syndromes. Refinement of cytogenetic techniques, especially increase of banding resolution in conventional cytogenetic analysis, gave the clue to the correct diagnosis, which was proven by fluorescence in situ hybridization (FISH) with whole chromosome paints and single copy probes. We could show that he had an unbalanced translocation inherited from his father resulting in partial monosomy 18p and partial trisomy 20p. The combination of deletion 18p/duplication 20p was previously reported in three patients and seems to have a clinically recognizable face. © 2003 Wiley‐Liss, Inc.
EEC syndrome type 3 with a heterozygous germline mutation in the P63 gene and B cell lymphoma
Authors: Akahoshi Keiko , Sakazume Satoru , Kosaki Kenjiro , Ohashi Hirofumi , Fukushima Yoshimitsu
Published: June 2003

Lines of evidence have recently indicated a relationship between mutations in the P63 gene and ectrodactyly‐ectodermal dysplasia‐clefting (EEC) syndrome type 3 (EEC3). The p63 gene (P63) has homology to P53 known as a tumor‐suppressor gene, but biological function of its protein has not yet been known well. There have been two reported patients who had EEC syndrome associated with malignant lymphoma. However, they did not undergo sequencing analysis of P63. Here, we present with a Japanese girl who had EEC3 and developed diffuse large B‐cell type non‐Hodgkin lymphoma. In this patient, we documented a heterozygous germline mutation, Asp312Gly, in P63. We speculated that p63 may exert a biological function as a tumor suppressor. Malignant lymphoma should be considered as an important complication of EEC3. © 2003 Wiley‐Liss, Inc.
Johnson–McMillin syndrome, a neuroectodermal syndrome with conductive hearing loss and microtia: Report of a new case
Authors: Schweitzer Daniela N. , Yano Shoji , Earl Dawn L. , Graham John M.
Published: June 2003

In 1983, Johnson et al. described 16 related individuals with alopecia, anosmia or hyposmia, conductive hearing loss, microtia and/or atresia of the external auditory canal, and hypogonadotrophic hypogonadism inherited in an autosomal dominant pattern. Other less constant manifestations included facial asymmetry, mental retardation, congenital heart defect, cleft palate, and choanal stenosis. An isolated case was reported later (Johnston et al. [1987: Am J Med Genet 26: 925–927]) and thereafter an affected mother and son (Hennekam and Holtus [1993: Am J Med Genet 47: 714–716]). We describe an additional unrelated female patient with features resembling those of the previously reported cases. She presented with intrauterine growth deficiency, microcephaly, alopecia, bilateral microtia with canal atresia, conductive hearing loss, partial left facial palsy, posterior cleft palate, left choanal stenosis, tetralogy of Fallot, developmental delay, and right thumb polydactyly. Because the phenotypic abnormalities in this syndrome affect the brain, facial structures, ectoderm and its derivatives, outflow tract of the heart, and Rathke's pouch derivatives, this has suggested to previous authors etiologic involvement of the ectoderm and neuroectoderm of the first and second branchial arches, Rathke's pouch, and the diencephalon. Microtia with conductive hearing loss differentiates the condition from other ectodermal dysplasias. In the initial report, females appeared somewhat less affected than males, and there was male‐to‐male transmission. The mother of our patient manifests subtle features, which suggest she may be a mildly affected female. Additionally, there is a family history of early‐onset alopecia in the maternal grandfather's relatives. © 2003 Wiley‐Liss, Inc.
Vestibular dysfunction in adult patients with osteogenesis imperfecta
Authors: Kuurila K. , Kentala E. , Karjalainen S. , Pynnönen S. , Kovero O. , Kaitila I. , Grénman R. , Waltimo J.
Published: June 2003

Progressive hearing loss is a major symptom in osteogenesis imperfecta (OI), a genetic brittle bone disease. Vertigo is frequently associated with otosclerosis in which the hearing loss clinically resembles that in OI. Vertigo is also common in basilar impression (BI) found in up to 25% of adult OI patients. In order to evaluate the cause, frequency, and characteristics of vertigo in OI, 42 patients were studied by interview, clinical examination, and audiological examination supplemented with electronystagmography (ENG) and lateral skull radiography. Audiometry showed hearing loss in 25 patients (59.5%). Nine patients (21%) displayed abnormal skull base anatomy in the forms of basilar impression, basilar invagination, or both, all designated here as BI. Twenty‐two patients (52.4%) reported vertigo, mostly of floating or rotational sensation of short duration. Patients with hearing loss tended to have more vertigo than patients with normal hearing. Vertigo was not correlated with type of hearing loss or auditory brain‐stem response (ABR) pathology. ENG was abnormal in 14 patients (33.3%). No dependency was found between vertigo and deviant ENG results. Patients with BI tended to have more vertigo than patients with normal skull base but the difference was not statistically significant. Neither ENG pathology, nor the presence or type of hearing loss showed correlation with BI. In conclusion, vertigo is common in patients with OI. In most cases, it may be secondary to inner ear pathology, and in only some patients does BI explain it. Since some OI patients without BI or hearing loss also suffer from vertigo, further clinical and neurological studies are needed to define the pathogenesis of vertigo in OI. © 2003 Wiley‐Liss, Inc.
A novel mutation of keratin 9 in epidermolytic palmoplantar keratoderma combined with knuckle pads
Authors: Lu Yong , Guo Chenhong , Liu Qiji , Zhang Xiyu , Cheng Lin , Li Jiangxia , Chen Bingxi , Gao Guimin , Zhou Haibin , Guo Yishou , Li Yefu , Gong Yaoqin
Published: June 2003

Epidermolytic palmoplantar keratoderma (EPPK) is an autosomal dominantly inherited disease. We studied a family from Shandong, China, having patients suffering from EPPK with a unique symptom—knuckle pads. We noticed that both the hyperkeratosis and knuckle pads in the Chinese family were friction‐related. Candidate gene analysis was carried out using linkage analysis and direct sequencing. A novel L160F mutation in keratin 9 was found, and its effects on the secondary structure of keratin 9 were studied. We predict that the L160F mutation is also responsible for the knuckle pads in the family. Our study provides a new clue for the study of the function of keratin 9. © 2003 Wiley‐Liss, Inc.
A newly recognized autosomal recessive syndrome with abnormal vertebral ossification, rib abnormalities, and nephrogenic rests
Authors: Prefumo Federico , Homfray Tessa , Jeffrey Iona , Moore Isabella , Thilaganathan Baskaran
Published: June 2003

We describe three cases of a severe malformation syndrome in siblings of both sexes. The characteristic features observed were absent intrauterine ossification of an apparently normal cartilaginous spinal column; rib abnormalities, with unossified segments and posterior gaps; thoracic hypoplasia; and multiple intralobar nephrogenic rests in the kidneys. This syndrome can be identified in early pregnancy by ultrasound scans due to the lack of ossification of the thoraco‐lumbar spine and its association with increased nuchal translucency thickness. We suggest that this is a newly recognized autosomal recessive syndrome. © 2003 Wiley‐Liss, Inc.
Growth retardation, developmental delay, distinctive face, multiple endocrine abnormalities, and adenylyl cyclase dysfunction: A new syndrome?
Authors: Salerno M. , Amabile G. , Mandato C. , Di Maio S. , Lecora M. , Avvedimento E.V. , Andria G.
Published: June 2003

We report on a 17‐year‐old male with severe pre‐ and postnatal growth retardation, craniosynostosis, distinctive facial features, acanthosis nigricans, deafness, mental retardation and progressive multi‐organ involvement, particularly of the endocrine system, including hypothyroidism, hypogonadism, transitory hypoparathyroidism, and insulin resistance. In order to find a common mechanism explaining these multiple abnormalities, we searched for a possible defect in the signal transduction pathways from membrane to nucleus involving G‐protein coupled receptors (GPCR). Adenylyl cyclase activity was evaluated by assaying c‐AMP in the patient's cultured fibroblasts stimulated with several drugs and toxins acting on different effectors upstream of adenylyl cyclase. The preliminary results indicate a reduced cAMP accumulation in the patient, neither caused by constitutive activation of Gi nor inhibition of Gs signaling, and probably resulting from an alteration in the adenylyl cyclase system. The differential diagnosis with syndromes showing common clinical features with our patient is discussed. © 2003 Wiley‐Liss, Inc.
Perinatal‐lethal Gaucher disease
Authors: Mignot C. , Gelot A. , Bessières B. , Daffos F. , Voyer M. , Menez F. , Fallet Bianco C. , Odent S. , Le Duff D. , Loget P. , Fargier P. , Costil J. , Josset P. , Roume J. , Vanier MT. , Maire I. , Billette de Villemeur T.
Published: June 2003

Gaucher disease is a lysosomal storage disease caused by glucocerebrosidase deficiency. Although purely visceral in most cases, some Gaucher disease patients have neurological signs. Signs of Gaucher disease appear after a symptom‐free period, except in rare cases with fetal onset. The description of such cases was based mainly on single reports and siblings. We report here a series of perinatal‐lethal Gaucher disease cases highlighting the specificity of this phenotype. We retrospectively studied eight original cases of proven Gaucher disease with fetal onset. Non‐immune hydrops fetalis was present in all cases but one, and associated with hepatosplenomegaly, ichthyosis, arthrogryposis, and facial dysmorphy. The similarities between our cases and 33 previously described cases allow us to better delineate the perinatal‐lethal Gaucher disease phenotype. Hydrops fetalis, in utero fetal death and neonatal distress are prominent features. When hydrops is absent, neurological involvement begins in the first week and leads to death within three months. Hepatosplenomegaly is a major sign, and associated with ichthyosis, arthrogryposis, and facial dysmorphy in some 35–43% of cases. Perinatal‐lethal Gaucher disease is a specific entity defined by its particular course and signs that are absent in classical type 2 Gaucher disease. Our study provides clues to the diagnosis of this likely underdiagnosed condition, which must be biochemically confirmed in order to propose appropriate genetic counselling. © 2003 Wiley‐Liss, Inc.
Upper airway malformation associated with partial trisomy 11q
Authors: Zhao Hui‐quan , Rope Alan F. , Saal Howard M. , Blough‐Pfau Ruthann I. , Hopkin Robert J.
Published: June 2003

11q trisomy is associated with a recognizable pattern of multiple malformations. Review of the literature reveals the following recurrent themes common to complex and isolated 11q trisomy: mental retardation, pre‐ and postnatal growth retardation, hypotonia, a distinct pattern of facial features, congenital heart defects, and limb malformations. We report four patients with partial trisomy 11q, none of which arose from the common 11/22 translocation. Three of the four patients had the previously unreported finding of upper airway obstruction secondary to a malformed epiglottis. The critical region for this malformation appears to be 11q21‐23.2. © 2003 Wiley‐Liss, Inc.
Wisconsin syndrome in a patient with interstitial deletion of the long arm of chromosome 3: Further delineation of the phenotype
Authors: Ko Wai‐tai , Lam Wai‐fan , Lo Fai‐man , Chan Wing‐kwong , Lam Tak‐sum
Published: June 2003

Interstitial deletions of the long arm of chromosome 3 are uncommon. Most cases are related to the blepharophimosis–ptosis–epicanthus inversus syndrome (BPES), which is mapped to 3q23. We report on a case with a de novo chromosomal deletion of 3q23 and 3q25. We review the literature on the reported cases of 3q deletion and find that the condition of our patient is not typical of the BPES. Rather, she shares similarity to a patient with Wisconsin syndrome, first discovered in 1976. © 2003 Wiley‐Liss, Inc.
Prevalence of trisomy 21 following folic acid food fortification
Authors: Ray Joel G. , Meier Chris , Vermeulen Marian J. , Cole David E.C. , Wyatt Philip R.
Published: June 2003

Polymorphisms of maternal genes responsible for normal folate metabolism may be associated with an increased risk of fetal trisomy 21. By January 1998, most of Canada's flour was being fortified with folic acid. We investigated whether the prevalence of antenatally and postnatally detected trisomy 21 changed before and after folic acid food fortification. A total of 218,977 women underwent second trimester maternal serum screening for trisomy 21 in the 48 months before fortification and 117,986 women were screened in the 29 months after fortification. There were 375 identified cases of trisomy 21 before fortification (1.71 per 1,000), compared to 201 cases thereafter (1.70 per 1,000) for a crude prevalence ratio (PR) of 0.99 (95% confidence interval [CI] 0.84–1.18). The associated risk of trisomy 21 did not change after adjustment for mean maternal age (adjusted PR 0.99 [95% CI 0.82–1.19]). Similarly, no significant decline in the monthly prevalence of trisomy 21 was observed using autoregressive integrated moving average time series analysis (P = 0.24). In conclusion, we failed to observe a decline in the occurrence of trisomy 21 following folic acid food fortification. © 2003 Wiley‐Liss, Inc.
Medical geneticists' duty to warn at‐risk relatives for genetic disease
Authors: Falk Marni J. , Dugan R. Beth , O'Riordan Mary Ann , Matthews Anne L. , Robin Nathaniel H.
Published: June 2003

A patient who refuses to notify their relatives of potential at‐risk status brings a genetics provider to face conflicting ethical principles and ill‐defined legal precedent. Genetics professionals' views on the disclosure of patient information to at‐risk relatives have remained largely unexamined. Prior analyses have been limited to identifying factors contributing to genetics providers' self‐predicted responses in hypothetical scenarios. Our group was the first to examine the clinical experience of genetic counselors with this issue [Dugan et al., 2003]. We report here results from our follow‐up survey of medical geneticists who are members of either the American Society of Human Genetics and/or American College of Medical Genetics in an effort to identify their experiences in warning at‐risk relatives and the factors driving their decision‐making processes. Over two‐thirds of medical geneticists surveyed (69%, 143/206) believe they do bear responsibility to warn their patients' relatives when found to be at‐risk for genetic disease. One‐quarter (25%, 31/123) of medical geneticists who faced the dilemma of a patient refusing to notify their at‐risk relatives seriously considered disclosure to those at‐risk relatives without patient consent. Only four respondents proceeded to warn at‐risk relatives of their status. Whereas genetic counselors cited emotional issues as playing a primary role in their decision not to warn, medical geneticists identified patient confidentiality, eventual case resolution by other means, and legal liability as the major factors leading to non‐disclosure in 76% of actual scenarios. Responsibilities of medical geneticists, genetic counselors, and non‐genetics healthcare professionals facing this issue will need to be more clearly defined to provide optimal medical care within the bounds of acceptable practice. © 2003 Wiley‐Liss, Inc.
Ring 21 chromosome and a satellited 1p in the same patient: Novel origin for an ectopic NOR
Authors: Ki Anita , Rauen Katherine A. , Black Lauri D. , Kostiner Dana R. , Sandberg Per L. , Pinkel Daniel , Albertson Donna G. , Norton Mary E. , Cotter Philip D.
Published: June 2003

Nucleolus organizer regions (NORs) are present on the satellite stalks located on the short arms of the acrocentric chromosomes. NORs present on non‐acrocentric chromosomes (ectopic NORs) are rare and were reported in both phenotypically normal and abnormal individuals. We describe a patient, ascertained prenatally, with an ectopic NOR on 1p and a ring 21 chromosomes. Amniocentesis was performed at 27‐weeks gestation on a 19‐year‐old woman after identification of intrauterine growth retardation (IUGR) by ultrasound. Cytogenetic analysis of amniocytes from the fetus showed a mos 46,XX,1ps,r(21) (p11.2q22.3)[44]/45,XX,1ps,‐21[6] karyotype. Parental karyotypes were normal, indicating a de novo origin for these rearrangements in the fetus. Molecular cytogenetic characterization of the 1ps showed no loss of euchromatin and retention of the telomeric repeats. Characterization of the r(21) using array comparative genomic hybridization (CGH) identified that the deletion was approximately 5 Mb encompassing most of chromosome band 21q22.3. The ectopic NOR (1ps) was most likely derived from the acentric 21p fragment generated by the chromosome breakage event that lead to formation of the r(21) chromosome. This represents a novel mechanism for the origin of ectopic NORs. In addition, this study illustrates the importance of FISH analysis with telomeric and subtelomeric probes for characterization of chromosomes with ectopic NORs. © 2003 Wiley‐Liss, Inc.