bluuebunny/crossref_metadata_2025 huggingface dataset:
Heregulin and forskolin‐induced cyclin D3 expression in Schwann cells: Role of a CCAAT promoter element and CCAAT enhancer binding protein
Authors: Fuentealba Luis , Schworer Charles , Schroering Allen , Rahmatullah Mohammed , Carey David J.
Published: January 2004

Heregulin, a polypeptide growth factor, and forskolin, an adenylyl cyclase activator, synergistically stimulate expression of cyclin D3 and cell division in Schwann cells. Heregulin induces expression in Schwann cells of a luciferase reporter gene linked to the cyclin D3 promoter. Forskolin markedly augments reporter expression in the presence of heregulin. Deletion analysis identified several promoter sites that contribute to high‐level reporter expression in heregulin‐ and forskolin‐treated Schwann cells. A promoter fragment that contains 103 bp of 5′‐flanking sequence produced significant reporter expression in heregulin‐ and forskolin‐stimulated cells. Deletion of a consensus CCAAT site within this promoter fragment caused a nearly complete loss of reporter expression. Similar results were obtained when CCAAT site mutations were introduced into the promoter. Heregulin and forskolin increased steady‐state levels of CCAAT/enhancer binding protein‐β (C/EBPβ) in Schwann cells. Mobility shift assays identified proteins in Schwann cell nuclear extracts that formed stable complexes with the cyclin D3 CCAAT promoter element and were disrupted by anti‐C/EBPβ antibody. Transfection of Schwann cells with C/EBPβ cDNA increased cyclin D3 reporter expression. In contrast to these results, mutation of a cAMP response element in the cyclin D3 promoter had only a modest effect on heregulin‐ and forskolin‐stimulated reporter expression. These findings demonstrate that C/EBPβ plays a key role in the heregulin and cAMP‐dependent regulation of cyclin D3 expression in Schwann cells. © 2003 Wiley‐Liss, Inc.
Na,K‐ATPase α2 inhibition alters calcium responses in optic nerve astrocytes
Authors: Hartford April K. , Messer Miranda L. , Moseley Amy E. , Lingrel Jerry B. , Delamere Nicholas A.
Published: January 2004

Experiments were conducted to test the effect of 1 μM ouabain, an Na,K‐ATPase inhibitor, on capacitative calcium entry (CCE) and calcium responses elicited by ATP in rat optic nerve astrocytes. In the rat, 1 μM ouabain is sufficient to inhibit the α2 Na,K‐ATPase, but not the α1. Immortalized astrocytes derived from Na,K‐ATPase α2 homozygous knockout (KO) mice and wild‐type (WT) littermates were also used. Cytosolic calcium and sodium concentrations were measured using Fura‐2 and SBFI, respectively. The magnitude of the increase in cytosolic calcium concentration during CCE was significantly greater in rat astrocytes exposed to 1 μM ouabain. To measure calcium release from stores, cells were exposed to ATP in the absence of extracellular calcium. In astrocytes exposed to 1 μM ouabain, a significantly greater calcium response to ATP was observed. 1 μM ouabain was shown to inhibit ATP hydrolysis in membrane material containing Na,K‐ATPase α2 and α1 isoforms (rat muscle) but not in membranes containing only Na,K‐ATPase α1 (rat kidney). In intact astrocytes, 1 μM ouabain did not alter the cell‐wide cytosolic sodium concentration. In mouse Na,K‐ATPase α2 KO astrocytes, the calcium increase during CCE was significantly higher than in WT cells, as was the magnitude of the calcium response to ATP. In KO astrocytes, but not WT, the cytosolic calcium increase during CCE was insensitive to 1 μM ouabain. Taken together, the results suggest that selective inhibition of the Na,K‐ATPase α2 isoform has the potential to change calcium signaling and CCE. © 2003 Wiley‐Liss, Inc.
Induction of chemokines in human astrocytes by picornavirus infection requires activation of both AP‐1 and NF‐κB
Authors: Kwon Daeho , Fuller Alyson C. , Palma Joann P. , Choi In‐Hong , Kim Byung S.
Published: January 2004

Infection with different picornaviruses can cause meningitis/encephalitis in humans and experimental animals. To investigate the mechanisms of such inflammatory diseases, potential chemokine gene activation in human astrocytes was investigated following infection with Theiler's murine encephalomyelitis virus (TMEV), coxsackievirus B3 (CVB3), or coxsackievirus B4 (CVB4). We report that all these viruses are potent inducers for the expression of interleukin‐8 (IL‐8) and monocyte chemoattractant protein‐1 (MCP‐1) genes in primary human astrocytes, as well as in an established astrocyte cell line (U‐373MG). Further studies indicated that both activator protein‐1 (AP‐1) and NF‐κB transcription factors are required in the activation of chemokine genes in human astrocytes infected with various picornaviruses. Interestingly, the pattern of activated chemokine genes in human astrocytes is quite restricted compared to that in mouse astrocytes infected with the same viruses, suggesting species differences in gene activation. This may result in potential differences in the pathogenic outcome in each species. © 2003 Wiley‐Liss, Inc.
Remyelination of cytokine‐ or antibody‐demyelinated CNS aggregate cultures is inhibited by macrophage supplementation
Authors: Diemel Lara T. , Wolswijk Guus , Jackson Samuel J. , Cuzner M. Louise
Published: January 2004

Remyelination in CNS aggregate cultures is determined both by macrophage enrichment and the mode of demyelination. Despite the same degree of myelin loss, accumulation of MBP in anti‐MOG antibody‐demyelinated aggregates overtakes that of controls, while recovery is significantly delayed following IFN‐γ‐induced demyelination. In antibody‐treated cultures, remyelination was associated with a significant increase in culture supernatant levels of TGF‐β1, FGF‐2, and PDGF‐AA as well as an induction of TNF‐α immediately following removal of the demyelinating insult. The impaired recovery in IFN‐γ‐treated cultures, denoted by a significant reduction in TGF‐β1, was reversed by treatment with hrTGF‐β1. Macrophage supplementation of the cultures prior to the addition of either demyelinating agent induced a greater degree of myelin loss followed by incomplete remyelination in both cases. This failure to remyelinate was associated in both groups with a several‐fold elevation in TNF‐α and with modest increases in PDGF‐AA and FGF‐2 in the antibody‐treated cultures. In contrast, macrophage supplementation to mature cultures in the absence of any demyelinating treatment resulted in enhanced accumulation of MBP associated with a promyelinative growth factor and TNF‐α profile similar to that in aggregates enriched with macrophages at the outset of the culture period. Hence, effector elements of the adaptive immune response appear to override promyelinogenic in favor of proinflammatory macrophage factors in mature CNS aggregates, counteracting the potential for myelin repair. © 2003 Wiley‐Liss, Inc.
CD44‐independent hepatocyte growth factor/c‐Met autocrine loop promotes malignant peripheral nerve sheath tumor cell invasion in vitro
Authors: Su Weiping , Gutmann David H. , Perry Arie , Abounader Roger , Laterra John , Sherman Larry S.
Published: January 2004

Malignant peripheral nerve sheath tumors (MPNSTs) are invasive peripheral nerve neoplasms that express both the receptor tyrosine kinase c‐Met and its ligand hepatocyte growth factor (HGF). The combined expression of these proteins has been implicated in tumor cell growth and metastasis. However, HGF/c‐Met autocrine activity requires the presence of a serine protease, the HGF activator (HGFA), and, in some cells, the CD44 transmembrane glycoprotein. Here, we found that HGFA, HGF, c‐Met, and CD44 are coexpressed in MPNSTs but their localization did not correlate with increased cell proliferation. The ST8814 MPNST cell line also expresses all of these proteins, can convert pro‐HGF to active HGF, and exhibits constitutive c‐Met phosphorylation. Blocking c‐Met activity or expression inhibits the invasive behavior of these cells but not their proliferation. Interestingly, although a CD44 splice variant contributes to MPNST cell invasion and interacts with c‐Met and HGF in ST8814 cells, it is not required for c‐Met activation. These data indicate that an HGF/c‐Met autocrine loop can promote MPNST invasion through a CD44‐independent mechanism and suggest that c‐Met, HGFA, and HGF are potential molecular targets to inhibit MPNST metastasis. © 2003 Wiley‐Liss, Inc.
Absolute rate constants for the gas‐phase ozonolysis of isoprene and methylbutenol
Authors: Klawatsch‐Carrasco N. , Doussin J. F. , Carlier P.
Published: January 2004

The reactions of the biogenic organic compounds isoprene and 2‐methyl‐3‐buten‐2‐ol (MBO) with ozone have been investigated under controlled conditions for pressure (atmospheric pressure) and temperature (293 ± 2 K), using FTIR spectrometry. CO was added to scavenge hydroxyl radical formation during the ozonolysis experiments. Reaction rate constants were determined by absolute rate technique, by measuring both ozone and the organic compound concentrations. The measured values were k1 = (1.19 ± 0.09) × 10−17 cm3 molecule−1 s−1 for the reaction between ozone and isoprene and k2 = (8.3 ± 1.0) × 10−18 cm3 molecule−1 s−1 for the reaction between ozone and MBO. © 2004 Wiley Periodicals, Inc. Int J Chem Kinet 36: 152–156 2004
Quantum chemical/vRRKM study on the thermal decomposition of cyclopentadiene
Authors: Tokmakov I. V. , Moskaleva L. V. , Lin M. C.
Published: January 2004

Thermal decomposition of cyclopentadiene to c‐C5H5 (cyclopentadienyl radical) + H (1) and the reverse bimolecular reaction (−1) are studied quantum‐chemically at the G2M level of theory. The dissociation pathway has been mapped out following the minimum energy path on the potential energy surface (PES) calculated by the density functional UB3LYP/6‐311G(d,p) method. Using isodesmic reaction analysis, the standard enthalpy of formation for c‐C5H5 is found to be 62.5 ± 1.3 kcal mol−1, and the c‐C5H5H bond dissociation energy is estimated as D°298(c‐C5H5H) = 82.5 ± 0.9 kcal mol−1, in excellent agreement with the recent experimental values. Variational rate constants are computed on the basis of a scaled UB3LYP dissociation potential that fits the isodesmic/experimental enthalpy of Reaction (1). At the high pressure limit, k1∞ = 1.55 × 1018 T−0.8 exp(−42300/T) s−1 and k−1∞ = 2.67 × 1014 exp(−245/T) cm3 mol−1 s−1. The fall‐off effects are evaluated by a weak collision master equation/RRKM analysis. Calculated T, P‐dependent rate constants are in very good agreement with the most reliable experimental measurements. © 2004 Wiley Periodicals, Inc. Int J Chem Kinet 36: 139–151 2004
Computational study on the kinetics and mechanisms for the reactions of HCO with HONO and HNOH
Authors: Xu Z. F. , Lin M. C.
Published: January 2004

The kinetics and mechanisms of the HCO reactions with HONO and HNOH have been studied at the G2M level of theory based on the geometric parameters optimized at BH&HLYP/6‐311G(d,p). The rate constants in the temperature range 200–3000 K at different pressures have been predicted by microcanonical RRKM and/or variational transition state theory calculations with Eckart tunneling corrections. For the HCO + HONO reaction, hydrogen abstraction from trans‐HONO and cis‐HONO by HCO produces H2CO + NO2, with the latter being dominant. Two other channels involving cis‐HONO by the association/decomposition mechanism via the HC(O)N(O)OH intermediate, which could fragment to give H2O + CO + NO at high temperatures, were also found to be important. For the HCO + HNOH reaction, three reaction channels were identified: one association reaction giving a stable intermediate, HC(O)N(H)OH (LM2), and two hydrogen abstraction channels producing H2CO and H2NOH. The dominant products were predicted to be the formation of LM2 at low temperatures and H2NOH + CO at middle and high temperatures. © 2004 Wiley Periodicals, Inc. Int J Chem Kinet 36: 178–187 2004
Kinetics and mechanism of oxidation of 2‐mercaptosuccinic acid by bis(μ‐oxo)‐ manganese(III,IV)‐cyclam complex in aqueous medium: Influence of externally added copper(II)
Authors: Shaikh Nizamuddin , Panja Anangamohan , Banerjee Pradyot
Published: January 2004

Kinetic studies on the oxidation of 2‐mercaptosuccinic acid by dinuclear [Mn2III/IV(μ‐O)2(cyclam)2](ClO4)3] (1) (abbreviated as MnIII–MnIV) (cyclam = 1,4,8,11‐tetraaza‐cyclotetradecane) have been carried out in aqueous medium in the pH range of 4.0–6.0, in the presence of acetate buffer at 30°C by UV–vis spectrophotometry. In the pH region, two species of complex 1 (MnIII–MnIV and MnIII–MnIVH, the later being μ‐O protonated form) were found to be kinetically significant. The first‐order dependence of the rate of the reactions on [Thiol] both in presence and absence of externally added copper(II) ions, first‐order dependence on [Cu2+] and a decrease of rate of the reactions with increase in pH have been rationalized by suitable sequence of reactions. Protonation of μ‐O bridge of 1 is evidenced by the perchloric acid catalyzed decomposition of 1 to mononuclear Mn(III) and Mn(IV) complex observed by UV–vis and EPR spectroscopy. The kinetic features have been rationalized considering Cu(RSH) as the reactive intermediate. EPR spectroscopy lends support for this. The formation of a hydrogen bonded outer‐sphere adduct between the reductant and the complex in the lower pH range prior to electron transfer reactions is most likely to occur. © 2004 Wiley Periodicals, Inc. Int J Chem Kinet 36: 170–177 2004
Relative reactivity and kinetic pattern of aniline and N‐methylaniline as nucleophiles in aromatic substitution (SNAr) reactions
Authors: Emokpae Thomas A. , Isanbor Chukwuemeka
Published: January 2004

Kinetic results are reported for the reactions of 4‐nitrophenyl‐2,4,6‐trinitrophenyl ether 3 with aniline and N‐methylaniline in dimethyl sulphoxide, acetonitrile, methanol, and benzene. The reactions gave the expected 2,4,6‐trinitrodiphenylamine and were base catalyzed in all the solvents. Both nucleophiles showed the same kinetic pattern under the same reaction conditions but aniline was found to be considerably more reactive than N‐methylaniline. The greater catalytic efficiency of aniline over N‐methylaniline is consistent with the proton transfer mechanism of the base‐catalyzed step. Dichotomy of amine effects in aromatic substitution (SNAr) reactions is discussed. © 2004 Wiley Periodicals, Inc. Int J Chem Kinet 36: 188–196, 2004
High‐performance V‐band monolithic quadruple sub‐harmonic mixer with anti‐parallel diode pair
Authors: Uhm Won‐Young , Sul Woo‐Suk , Lee Han‐Shin , Kim Sam‐Dong , Park Hyung‐Moo , Rhee Jin‐Koo
Published: January 2004

A high‐performance V‐band quadruple subharmonic mixer monolithic circuit is fabricated using the millimeter‐wave monolithic integrated circuit (MIMIC) process. Due to the superior features of the anti‐parallel diode pair (APDP) and the utilization of a quarter of fundamental frequency, the proposed subharmonic mixer shows good conversion‐gain and isolation characteristics. Maximum conversion gain of 0.8 dB at an LO frequency of 14.5 GHz and an RF frequency of 60.4 GHz is measured. Both LO‐to‐RF and LO‐to‐IF isolations are higher than 50 dB in the operation mode. © 2004 Wiley Periodicals, Inc. Microwave Opt Technol Lett 40: 349–352, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.11378
3D photo‐induced load modeling for optically controlled microwave microstrip line
Authors: Arnould J.‐D. , Gary R. , Vilcot A.
Published: January 2004

This paper deals with the 3D modeling of the photo‐induced load created by a laser that illuminates a semiconductor substrate. This independent optical command allows us to change the microwave behavior of the microstrip device. We present a 3D‐equivalent microwave model for the photo‐injection in terms of equivalent conductivity plasma. © 2004 Wiley Periodicals, Inc. Microwave Opt Technol Lett 40: 356–359, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.11380
Quad‐band internal monopole mobile‐phone antenna
Authors: Lee Gwo‐Yun , Wong Kin‐Lu
Published: January 2004

A novel internal monopole antenna suitable for applications in AMPS/GSM/DCS/PCS quad‐band mobile phones is presented. The antenna comprises two orthogonal wideband monopole elements for operation at about 900 and 1850 MHz, covering the APMS/GSM (824–894/890–960 MHz) and DCS/PCS (1710–1880/1850–1990 MHz) bands, respectively. The quad‐band monopole antenna is also arranged in a compact structure such that it has a low profile (only 6 mm in this study) and protrudes from the top edge of the system ground plane of a communications device, thus making it very promising as an internal antenna, built‐in within the device's casing. © 2004 Wiley Periodicals, Inc. Microwave Opt Technol Lett 40: 359–361, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.11381
Characteristics of microfabricated rectangular coax in the Ka band
Authors: Brown E. R. , Cohen A. L. , Bang C. A. , Lockard M. S. , Byrne B. W. , Vandelli N. M. , McPherson D. S. , Zhang G.
Published: January 2004

Miniaturerectangularcoaxial transmission line (with a 300 × 300 μm outer conductor) is simulated, fabricated, and tested up to the Ka band. It is made by the electrochemical fabrication (EFAB™) of nickel such that the center conductor is supported primarily by ≈λ/4 stubs that also establish a resonant passband. The minimum insertion loss of a 1.67‐cm‐long test structure is found to be 1.74 dB at the passband center of 29 GHz. This is within 0.57 dB of the lowest insertion loss predicted by full‐wave numerical simulations, indicative of the high precision and smooth surface morphology of the EFAB process. © 2004 Wiley Periodicals, Inc. Microwave Opt Technol Lett 40: 365–368, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.11383
Study on PMD of conventional single mode fiber transmitting system with FBG for dispersion compensation
Authors: Li Pei , Li Tangjun , Yan Fengping , Jian Wei , Ning Tigang , Jian Shuisheng
Published: January 2004

The maxim tolerance of polarization‐mode dispersion (PMD) in transmission systems at different rates is analyzed in this paper for the first time. The PMD of two transmission systems are measured and analyzed for dispersion compensation through conventional single‐mode fiber (G.652) with fiber Bragg gratings (FBGs). The results show that PMD compensation in the 10‐Gb/s transmission system is not necessary, but the PMD must be compensated in the 40‐Gb/s transmission system. We compensate it by using a short length of polarization maintain fiber (PMF), and obtain good results. © 2004 Wiley Periodicals, Inc. Microwave Opt Technol Lett 40: 371–374, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.11385
A printed folded Koch monopole antenna for wireless devices
Authors: Tsachtsiris G. , Soras C. , Karaboikis M. , Makios V.
Published: January 2004

A novel folded Koch monopole antenna printed over a wireless device's ground plane is presented. Due to its favorable characteristics, the element was further considered for the implementation of a two‐branch diversity system and proved to achieve a good diversity performance under both switched and combining schemes. © 2004 Wiley Periodicals, Inc. Microwave Opt Technol Lett 40: 374–378, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.11386
Loss analysis of single‐mode fiber/photonic‐crystal fiber splice
Authors: Hoo Yeuk Lai , Jin Wei , Ju Jian , Ho Hoi Lut
Published: January 2004

The connection loss between single‐mode fiber and photonic crystal fiber (PCF) is analyzed by using a full‐vector finite‐element method. PCF parameters for achieving low loss connection (for example, less than 0.5 dB) are reported. © 2004 Wiley Periodicals, Inc. Microwave Opt Technol Lett 40: 378–380, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.11387
Automatic image generation (AIG) technique for efficient and systematic multiresolution time‐domain (MRTD) analysis
Authors: Zhu Yanjie , Chen Yinchao , Yang Mingwu , Mittra Raj
Published: January 2004

Although the multiresolution time‐domain (MRTD) scheme has excellent potential as a Maxwell solver, the numerical implementation of the time updating in this scheme in a region near an inhomogenous material interface, as well as the incorporation of boundary truncation on the shielded structure, is quite involved and prevents the extensive application of this method to complex geometries. In this paper we try to ease this computational burden, without sacrificing accuracy, by presenting a simplified version of the MRTD that employs a diagonal matrix approximation for material‐related MRTD matrices. Additionally, we develop an automatic image generation (AIG) technique to truncate a perfectly electric conductor (PEC) shield or a hybrid PEC‐open boundary for the image fields. The algorithm is validated for a number of shielded resonant cavity structures that are filled with different dielectric materials with varying sizes and orientations. It is found that the results presented in this work agree well with those obtained from analytical solutions and the application of the finite‐difference time‐domain (FDTD) method. The MRTD algorithm, presented herein, realizes considerable savings in memory and CPU time, in comparison to the conventional counterparts, while retaining the flexibility of the FDTD method. © 2004 Wiley Periodicals, Inc. Microwave Opt Technol Lett 40: 380–386, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.11388
Mutual coupling compensation in narrowband small linear‐antenna arrays
Authors: Hossa R. , Bialkowski M.
Published: January 2004

This paper presents least squares (LS) and total least squares (TLS) method solutions to compensate mutual coupling effects in a small linear antenna array operating over a narrow frequency band. The validity of the two methods is verified by experimental results performed on a six‐element microstrip patch array operating in the 2.4‐GHz band. The obtained results prove the validity of the two methods and show the superiority of the TLS method over the LS method. © 2004 Wiley Periodicals, Inc. Microwave Opt Technol Lett 40: 391–396, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.11390
A study on rectangular microstrip antenna with group of slots for compact operation
Authors: Vani R. M. , Farida S. F. , Hunagund P. V.
Published: January 2004

The compact configuration of a microstrip antenna can be realized by embedding suitable slots on the radiating patch. In this paper, a typical configuration of slots is studied by putting group of vertical slots near radiating edge with inset feed and the experimental results are presented. © 2004 Wiley Periodicals, Inc. Microwave Opt Technol Lett 40: 396–398, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.11391
A new ultra‐wideband antenna for UWB applications
Authors: Choi Seok H. , Park Jong K. , Kim Sun K. , Park Jae Y.
Published: January 2004

In this paper, we propose a new ultra‐wideband (UWB) antenna for UWB applications. The proposed antenna is designed to operate from 3.2 to 12 GHz. It consists of a rectangular patch with two steps, a single slot on the patch, and a partial ground plane. Details of the proposed antenna design and measured results are presented and discussed. © 2004 Wiley Periodicals, Inc. Microwave Opt Technol Lett 40: 399–401, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.11392
An electronically controlled transmission‐line phase shifter
Authors: Shin Chang‐Seok , Nevels Robert , Strieter Frederick , Biard J. Robert
Published: January 2004

An investigation of a microstrip transmission line in which a measure of electronic control over the wave propagation constant can be achieved is presented. The microstrip line is constructed with an adjustable‐width upper plate, obtained by placing a DC bias across the p+and n+strips in doped silicon. A change in the forward‐voltage bias across the silicon strip changes the current amplitude, which in turn affects a change in the conductivity of the silicon. This change in the conductivity of the silicon semiconductor produces a change in the effective width of the microstrip line, thus producing a phase shift in a high‐frequency signal propagating in the line. An electronically controlled transmission line (ECTL) has applications as a feed line for a traveling wave‐array antenna. © 2004 Wiley Periodicals, Inc. Microwave Opt Technol Lett 40: 402–406, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.11393
Enhancement of Brillouin stokes powers in multiwavelength fiber laser utilizing band‐pass filter
Authors: Saharudin S. , Abdullah M. K. , Mahdi M. A.
Published: January 2004

We report an increased number of stokes when used with a band‐pass filter in multiwavelength Brillouin erbium‐doped fiber laser (BEFL). A total of 15 Stokes were achieved as compared with seven in a system without the band‐pass filter. The efficiency of generating Brillouin Stokes improved due to the suppression of out‐of‐band amplified spontaneous emission in the BEFL. The band‐pass filter provides a specific range of lasing window that coincide with the Brillouin pump signal. The flatness of the Brillouin stokes is also improved in the proposed design. © 2004 Wiley Periodicals, Inc. Microwave Opt Technol Lett 40: 408–410, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.11395
Symbol rate and signal capture in LMDS systems
Authors: Cheng D.
Published: January 2004

Based on the Monte‐Carlo simulation of frequency tolerance and drift parameters in the microwave local multipoint distribution service (LMDS) systems, the relationships among symbol rate, temperature variation, and signal capture probability are investigated. To guarantee 100% probability of signal capture, symbol rate limitations are presented. © 2004 Wiley Periodicals, Inc. Microwave Opt Technol Lett 40: 418–420, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.11397
Multifrequency dielectric EBG antenna
Authors: Leger Ludovic , Granger Raphaël , Thevenot Marc , Monediere Thierry , Jecko Bernard
Published: January 2004

This paper describes how to design an electromagnetic band gap (EBG) resonator antenna to radiate directive patterns for multiple frequencies. The principle is explained and applied to a GSM/DCS antenna. A prototype which is smaller than the GSM/DCS antenna for ease of manufacture, is realized. The operating frequencies are 4.2 GHz and 7.4 GHz. © 2004 Wiley Periodicals, Inc. Microwave Opt Technol Lett 40: 420–423, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.11398
Continuous hybrid approach to the modified resonant frequency calculation for circular microstrip antennas with and without air gaps
Authors: Günel Tayfun
Published: January 2004

In this work, a continuous hybrid approach (CHA) to the modified resonant frequency calculation for circular microstrip antennas with and without air gaps is presented. The results obtained by the CHA for different antenna dimensions and modes of resonance are compared with the experimental and theoretical results given in the literature. © 2004 Wiley Periodicals, Inc. Microwave Opt Technol Lett 40: 423–427, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.11399
An accurate and logically correct way to verify the numerical dispersion relations of FDTD and ADI‐FDTD methods
Authors: Zhao An Ping , Mäkinen Riku M.
Published: January 2004

It is well known that the numerical dispersion relations of all kinds of finite‐difference time‐domain (FDTD) methods, including the conventional FDTD and alternating‐direction implicit (ADI) FDTD methods, are derived from the assumption of plane wave. In the past, however, disregarding the above fact, a point source that creates a cylindrical wave was used to numerically validate the numerical dispersion relations of the FDTD‐related methods. Strictly speaking, using the point source for the validation is illogical and also incorrect. This is due to the fact that the numerical dispersion relation of the cylindrical wave differs from that of the plane wave. It is demonstrated in this paper that the phase velocity calculated from the point source strongly depends on the positions of the observation points, and that the calculated phase velocity never exactly matches the theoretical prediction, even though the phase velocity of the cylindrical wave gets closer to that of the plane wave when the observation points are located far away from the point source (that is, when the cylindrical wave can be approximately treated as the plane wave). On the contrary, numerical tests indicate that, no matter where the observation points are located, the phase velocity obtained using plane‐wave excitation agrees extremely well with the theoretical values. We can therefore conclude that to more accurately and logically verify the numerical dispersion relations of any kinds of FDTD‐related algorithms, plane‐wave excitation has to be employed. © 2004 Wiley Periodicals, Inc. Microwave Opt Technol Lett 40: 427–431, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.11400
Pulmonary effects of gastroschisis in a fetal rabbit model
Authors: Biard Jean‐Marc , Lu Hui Qi , Vanamo Kari , Maenhout Benedikte , De Langhe Ellen , Verbeken Erik , Deprest Jan
Published: January 2004

Respiratory insufficiency is a significant cause of mortality and morbidity among infants with anterior abdominal wall defects (AWD). The aim of this study was to evaluate the pulmonary effects in a fetal rabbit model where gastroschisis was induced at midgestation. Gastroschisis (GAS) was created in 20 rabbit fetuses on day 22 or 23 of gestation (pseudoglandular phase; term = 31–32 days). The amniotic sacs of 13 fetuses were subjected to hysterotomy and amniotomy only (HYST), while 13 underwent a sham laparotomy which was immediately closed by sutures (SHAM). Eleven nonoperated littermates served as internal controls (CTR). Fetuses were harvested by cesarean section on day 31 of gestation prior to respiration. Pulmonary response was evaluated by left lung to body weight ratio (LWBWR), airway morphometry, and density of type II pneumocytes, as evaluated by the number of surfactant protein B‐positive cells. Fetuses from the GAS group had significantly lower body weights than did CTR (P = 0.0129). Of these fetuses, 27% were growth‐restricted, i.e., with a body weight under the 10th percentile of the CTR population. There were no differences in left lung weight and LWBWR among the GAS and CTR groups. Moreover, the GAS group had similar alveolar size, alveolar wall thickness, and type II cell density as CTR fetuses. Only mean terminal bronchiolar density (MTBD), which is inversely related to the alveolar space, was slightly increased in the GAS group, but without reaching significance (P = 0.0821). No effect on lung growth and maturation could be demonstrated in this study. Pediatr Pulmonol. 2004; 37:99–103. © 2004 Wiley‐Liss, Inc.
Effect of high‐dose fluticasone propionate on bone density and metabolism in children with asthma
Authors: Griffiths Amanda L. , Sim Derrick , Strauss Boyd , Rodda Christine , Armstrong David , Freezer Nicholas
Published: January 2004

Significant concern remains over the long‐term side effects of inhaled steroids. This cross‐sectional study evaluates the effect of high‐dose inhaled fluticasone propionate (FP) on biochemical markers of bone metabolism and bone density in children with asthma. Children with chronic asthma using FP ≥ 1,000 mcg daily for at least 6 months, and healthy controls, were entered in the study. No children had taken oral prednisolone within the previous month. Fasting morning serum was analyzed for bone formation markers, and spot urine for bone resorption markers. Dual‐energy X‐ray absorptiometry (DEXA) results were reviewed in a subgroup of patients. Forty‐nine children with asthma and 32 controls were recruited. The mean FP dose was 771.2 ± 253.35 mcg/m2/day. Unpaired t‐test analysis revealed no significant difference in biochemical markers studied. In subjects with asthma; 13 of 37 (35.1%) had lumbar spine density more than one standard deviation below the mean (P = 0.001). This fell to 6/37 (16.2%) with bone age correction (NS). In conclusion, no significant reduction in bone metabolism or bone age‐corrected bone mineral density was observed in children with asthma on prolonged high doses of inhaled FP. Pediatr Pulmonol. 2004; 37:116–121. © 2004 Wiley‐Liss, Inc.
Effects of inhaled fluticasone propionate in children less than 2 years old with recurrent wheezing
Authors: Teper Alejandro M. , Colom Alejandro J. , Kofman Carlos D. , Maffey Alberto F. , Vidaurreta Santiago M. , Bergadá Ignacio
Published: January 2004

Our objective was to evaluate the efficacy and safety of two doses of fluticasone propionate (FP) in young children with recurrent wheezing and risk factors for asthma. Our study design was a randomized, double‐blind, placebo‐controlled comparison of inhaled FP 50 mcg twice daily (FP 100) and 125 mcg twice daily (FP 250), for 6 months. Outcome measures included number of wheezing episodes, days on albuterol, height standard deviation score (height SDS), osteocalcin (OC), bone alkaline phosphatase fraction (AKP), insulin‐like growth factor‐binding protein 3 (IGFBP‐3), and serum levels of cortisol (SC). Our subjects were 30 patients, aged 7–24 months. Mean wheezing episodes were 6.0 ± 1.9, 1.9 ± 1.9, and 2.8 ± 1.2; mean days of albuterol use were 24.3 ± 1.3, 6.5 ± 0.8, and 9.1 ± 0.8, per patient for placebo, FP100, and FP250 groups, respectively. There was a significant reduction in clinical outcome in the two FP groups compared to placebo (P < 0.01). No significant correlations were found between FP dosage and height SDS, OC, AKP, IGFBP‐3, and SC. In conclusion, in young children with asthmatic symptoms, FP at 50 and 125 mcg b.i.d. for 6 months significantly improved respiratory symptoms without causing significant side effects on growth and bone metabolism. Pediatr Pulmonol. 2004; 37:111–115. © 2004 Wiley‐Liss, Inc.
Reduction in prevalence of chronic Pseudomonas aeruginosa infection at a regional pediatric cystic fibrosis center
Authors: Lee Tim W.R. , Brownlee Keith G. , Denton Miles , Littlewood James M. , Conway Steven P.
Published: January 2004

Various management strategies were introduced at the Leeds Regional Cystic Fibrosis (CF) Unit in an attempt to reduce the prevalence of chronic Pseudomonas aeruginosa respiratory infection, previously thought to be inevitable in most children with CF. These included neonatal screening (1975), regular microbiological monitoring (1975), early antibiotic treatment of first isolations of P. aeruginosa (1985), intensive intravenous antibiotic treatment where nebulized antibiotics failed to eradicate P. aeruginosa (1988), and separate clinics for patients chronically infected with P. aeruginosa and uninfected patients (1991). The aim of this study was to assess the impact of these interventions. All 232 patients receiving full‐time care at the Leeds Paediatric CF Centre during the period January 1990–December 2000 were categorized into four groups: never grown P. aeruginosa; free of P. aeruginosa for at least 1 year; intermittent grower of P. aeruginosa with ≤50% of months with samples positive for P. aeruginosa over the previous 12 months; and chronic P. aeruginosa infection with >50% of months with samples positive for P. aeruginosa over the previous 12 months. The yearly prevalence of patients having chronic P. aeruginosa infection fell significantly during the study, from 24.5% in 1990 to 18.1% in 2000 (P < 0.05), despite an increase in mean age of patients from 7.73 to 9.42 years. The number of patients aged less than 11 years who had chronic P. aeruginosa infection fell from 23.8% in January 1990 to only 4.3% by December 2000. The annual incidence and mean age of first acquisition of P. aeruginosa did not alter significantly. In conclusion, antipseudomonal management strategies were associated with both reduced prevalence, and an increase in the mean age of onset of chronic P. aeruginosa infection. Pediatr Pulmonol. 2004; 37:104–110. © 2004 Wiley‐Liss, Inc.
Efficacy and safety of formoterol turbuhaler® when added to inhaled corticosteroid treatment in children with asthma
Authors: Zimmerman Barry , D'Urzo Anthony , Bérubé Denis
Published: January 2004

This double‐blind, placebo‐controlled, randomized, parallel‐group, multicenter study was conducted in 302 children aged 6–11 years with asthma not optimally treated with inhaled corticosteroids alone. Patients continued with their existing dose of inhaled corticosteroids and in addition received placebo, formoterol 4.5 μg or formoterol 9 μg b.i.d., for 12 weeks (all delivered via Turbuhaler®). Terbutaline was available as reliever medication. The primary efficacy variable was change from baseline in morning peak expiratory flow (PEF); secondary efficacy variables included forced expiratory volume in 1 sec (FEV1), serial PEF measured over 12 hr, evening PEF, asthma symptom score, and quality of life. Compared with placebo, formoterol 4.5 μg and 9 μg improved morning PEF by 8 l/min (P = 0.035) and 11 l/min (P = 0.0045), respectively. Evening PEF and FEV1 were also significantly increased compared with placebo, with no statistically significant difference between formoterol doses. Lung‐function improvements compared with placebo were greater in the middle of the day. Twelve‐hour average serial PEF after 3 months increased by 24 l/min (95% CI, 9, 39 l/min) in the formoterol 9‐μg group, and by 14 l/min (95% CI, 0, 29 l/min) in the formoterol 4.5‐μg group. The incidence of severe exacerbations in both formoterol groups was numerically lower than in the placebo group, indicating that formoterol may have the potential to improve exacerbation control in children. Both formoterol doses were well‐tolerated, and tolerance to the drug's bronchodilator effect was not observed. Formoterol provided sustained improvements in lung function and was well‐tolerated in children with asthma suboptimally treated with inhaled corticosteroids alone. Pediatr Pulmonol. 2004; 37:122–127. © 2004 Wiley‐Liss, Inc.
Bringing new treatments to the bedside in cystic fibrosis
Authors: Brennan Amanda L. , Geddes Duncan M.
Published: January 2004

The discovery of the cystic fibrosis transmembrane conductance regulator gene in 1989 led to a dramatic increase in the understanding of the molecular basis of CF. Increased knowledge has provided the opportunity to target drug development at correcting the basic defect either by gene therapy or pharmacological modulation of the abnormal physiological processes.

Development of new medications for the CF population poses many challenges. The discovery and development of new medications is always time consuming and expensive. Since CF affects a small population worldwide, the potential for a drug company to profit from a new treatment is limited. In addition, each new therapy must have an additional and proven benefit to be attractive to clinicians and consumers, otherwise it will not be commercially viable. Demonstrating clinical benefit is problematic as a limited number of patients are available to participate in clinical trails and outcome measures, such as length of life, are hard to measure.

In this review we will illustrate these challenges by discussing the development of treatments which have successfully reached the bedside and those that were unsuccessful. Pediatr Pulmonol. 2004; 37:87–98. © 2004 Wiley‐Liss, Inc.
Harvesting airway surface liquid: A comparison of two techniques
Authors: Landry Jennifer S. , Landry Champlain , Cowley Elizabeth A. , Govindaraju Karuthapillai , Eidelman David H.
Published: January 2004

The quantity and composition of airway surface liquid (ASL) are essential to host defense. To date, attempts to harvest ASL and measure its composition have yielded conflicting results. We investigated the physical principles underlying two techniques that were proposed for harvesting ASL: filter paper pledgets and polyethylene catheters. We compared the force and pressure generation and the kinematics of capillarity‐induced fluid uptake with both techniques. Both have significant limitations for harvesting ASL, generating physiologically significant pressures (filter paper, 60.4 Pa; polyethylene, 14.3 Pa) that could potentially compromise epithelial integrity. Furthermore, filter paper generates a force 85‐fold higher than the polyethylene catheter, which is associated with a very high rate of uptake of liquid and a large total amount of liquid relative to ASL thickness. While the PE catheter harvests liquid more gently, it is only effective when ASL surface tension is below 31 mN/m. These limitations likely account for some of the variability in reported ASL composition, and highlight the need for improved methods for harvesting ASL. Pediatr Pulmonol. 2004; 37:149–157. © 2004 Wiley‐Liss, Inc.
Nodular pulmonary vasculitis in a twelve‐year‐old boy
Authors: Borchers T. , Dirsch O. , Schaper J. , Kreuzfelder E. , Jakob H. , Ratjen F.
Published: January 2004

A 12‐year‐old boy presented with left shoulder pain during physical exercise and complained of uncommon sweating and fatigue. Diagnostic evaluation revealed a solitary pulmonary nodule in the left upper lobe. All laboratory values were within normal limits, except for an elevated level of antineutrophil cytoplasmic antibodies directed against myeloperoxidase (p‐ANCA). Surgery was performed, and pathological examination showed a localized granulomatous vasculitis. Antineutrophil cytoplasmic antibodies directed against affinity purified proteinase 3 (p‐ANCA) concentrations returned to baseline within 6 months, and the patient has done well during a follow‐up period of 2 years. While nodular vasculitis is known to occur in Wegener's granulomatosis, to the best of our knowledge, this case represents the first c‐ANCA negative primary pulmonary vasculitis in childhood. Pediatr Pulmonol. 2004; 37:181–185. © 2004 Wiley‐Liss, Inc.
Pulmonary involvement in tuberous sclerosis
Authors: Vicente M.P. , Pons M. , Medina M.
Published: January 2004

Tuberous sclerosis is a neurocutaneous syndrome involving many tissues. Pulmonary involvement is rare. Pulmonary cases are usually women of child‐bearing age who present with spontaneous pneumothorax or progressive dyspnea. In childhood and, even more, in male patients, pulmonary involvement by tuberous sclerosis is exceptional. We report on a 4‐year‐old male patient diagnosed in the first months of life with tuberous sclerosis with predominantly respiratory symptoms (frequently with acute RDS criteria), in whom lung involvement was pathologically confirmed. Pediatr Pulmonol. 2004; 37:178–180. © 2004 Wiley‐Liss, Inc.
Insulin‐like growth factor‐1 (IGF‐1) and IGF‐1 receptor (IGF‐1R) expression in human lung in RDS and BPD
Authors: Chetty Anne , Andersson Sture , Lassus Patrik , Nielsen Heber C.
Published: January 2004

We hypothesize that IGF‐1 and IGF‐1R proteins are upregulated in lung epithelia and fibroblasts in RDS compared to normal development, and are further upregulated in BPD. We used immunohistochemistry to evaluate IGF‐1 and IGF‐R expression in lungs from autopsies of human stillbirths and RDS and BPD patients. IGF‐1 and IGF‐R immunostaining were present in fetal, RDS, and BPD lungs. In RDS, IGF‐1 was present in alveolar epithelium and prominent in columnar and cuboidal airway epithelia. In BPD lungs, immunostaining was intensely increased in both airway and alveolar epithelia and in mesenchyme. The immunostaining index in bronchial epithelial cells and peribronchial myofibroblasts was significantly higher in BPD compared to RDS. IGF‐1R expression was minimal in fetal lung and found mainly in mesenchyme. IGF‐1R was increased in mesenchyme in RDS. In BPD it was especially increased in peribronchial and perialveolar mesenchyme. Immunostaining index for IGF‐1R in epithelial cells and peribronchial myofibroblasts was increased in BPD compared to RDS. IGF‐1 and IGF‐R expression is low during fetal development, but is acutely upregulated in RDS, and persists with further upregulation in BPD. Pediatr Pulmonol. 2004; 37:128–136. © 2004 Wiley‐Liss, Inc.
BPI‐ANCA of pediatric cystic fibrosis patients can impair BPI‐mediated killing of E. coli DH5α in vitro
Authors: Schultz Hendrik , Schinke Susanne , Mosler Katharina , Herlyn Karen , Schuster Antje , Gross Wolfgang L.
Published: January 2004

Gram‐negative bacterial lung infections and chronic bacterial colonization are major threats for pediatric cystic fibrosis (CF) patients. Besides impeded mucociliary clearance, other mechanisms that contribute to increased susceptibility to infections are presumed. The bactericidal/permeability‐increasing protein (BPI), which is delivered by neutrophil granulocytes and mucosal epithelial cells, is one of the most potent innate antibiotics against Gram‐negative bacteria and endotoxin. Antineutrophil cytoplasmic autoantibodies against BPI (BPI‐ANCA) have been found in up to 90% of CF patients, and titers correlated inversely with lung function parameters. As major pulmonary damage is mediated by Gram‐negative bacteria and their products, the question was raised as to whether BPI‐ANCA can inhibit the antibiotic function of BPI in these patients. Sera of 23 pediatric CF patients were analyzed for the presence of BPI‐ANCA by indirect immunofluorescence, ELISA, epitope mapping, and Western blotting. Patients' IgG were tested in a bacterial growth inhibition assay with recombinant BPI (rBPI) and an amino‐terminal fragment of BPI (rBPI21) that retains antibiotic activity for inhibition of the antibiotic function of BPI against E. coli DH5α in vitro. BPI was recognized by 21 of 23 patients' sera in our detection assays. Thirteen of 23 patients' BPI‐ANCA (56%) could inhibit the antibiotic function in vitro. Moreover, epitope mapping over the whole BPI sequence revealed that more patients' BPI‐ANCA recognize the amino‐terminal part of BPI than can be detected by ELISA. Thus, in pediatric CF patients, BPI‐ANCA may contribute to diminished bacterial clearance by inhibiting the antibiotic function of BPI. Pediatr Pulmonol. 2004; 37:158–164. © 2004 Wiley‐Liss, Inc.