bluuebunny/crossref_metadata_2025 huggingface dataset:
Cytomegalovirus infection after orthotopic liver transplantation is restricted by a pre‐existing antiviral immune response of the recipient
Authors: Bissinger A.L. , Oettle H. , Jahn G. , Neuhaus P. , Sinzger C.
Published: March 2004

Infection of the liver by the human cytomegalovirus (HCMV) frequently occurs after orthotopic liver transplantation (OLT). However, the role of viral replication and the inflammatory reaction in the development of HCMV‐associated liver dysfunction is unclear. To address this question in vivo, 84 liver biopsy specimens from 74 patients who received an orthotopic liver transplant were investigated by immunohistochemical detection of viral antigens and cell type specific marker proteins. The extent of viral replication was correlated with the HCMV antibody status of donor and recipient. HCMV immediate early antigens were found in 25 of 84 liver tissue sections investigated, hepatocytes being the predominant target cells. Bile duct epithelial cells, endothelial cells, mesenchymal cells and sinusoidal lining cells were also found susceptible to HCMV infection. The detection of viral capsid antigens, nuclear inclusions in infected cells and foci of infected cells were suggestive of permissive infection in these cells. In 25 HCMV‐positive liver biopsy specimens, the median extent of HCMV infection was 0.33 (0.02–5.67) infected cells/mm2 liver tissue. Primary infection of liver transplant recipients (D+/R−) was associated with a significantly higher extent of organ involvement as compared to reinfection or reactivation (D+/R+). In contrast, the extent of inflammatory infiltrates in areas of infected liver cells was higher in tissues of patients with pre‐existing immunoreactivity (R+) compared to patients without pre‐existing immunoreactivity (R−). In conclusion, these results favour the assumption that the immune response to HCMV is effective in restricting viral spread in the liver. J. Med. Virol. 73:45–53, 2004. © 2004 Wiley‐Liss, Inc.
Human papillomavirus type specific DNA and RNA persistence—implications for cervical disease progression and monitoring
Authors: Cuschieri Kate S. , Whitley M.J. , Cubie Heather A.
Published: March 2004

In 2000, we monitored the course and persistence of human papillomavirus (HPV) infection in 54 women who were HPV positive and free of any cytological disease using HPV‐DNA genotyping with a linear array assay (baseline). The impact of HPV infection on development of cervical cytological abnormality (dyskaryosis) was monitored by repeat HPV genotyping and cytological assessment 2 years later. Detection of mRNA transcripts of known HPV oncogenes E6 and E7 using NASBA methodology and specific molecular beacons for five common HPV types was also performed at both time points. A total of 11/54 (20%) women developed dyskaryosis after 2 years with 31/54 and 23/54 women exhibiting transient and persistent infections respectively, as monitored by DNA genotyping. Women who maintained type‐specific persistent HPV infection were significantly more likely to develop dyskaryosis compared to those who exhibited a transient infection (P = 0.001). The presence of HPV mRNA E6/E7 transcripts was less sensitive but more specific for the detection of disease at follow up. Moreover, women who were DNA positive and also positive for mRNA transcripts at baseline were significantly more likely to harbour persistent infection compared to those in whom DNA only was detected at baseline (P = 0.013). This study highlights the importance of detecting persistent type specific HPV infection to identify those women more at risk of developing cervical abnormalities, either by repeated DNA genotyping, or potentially by RNA based techniques that may be more predictive of persistent infection if performed at a single time point. J. Med. Virol. 73:65–70, 2004. © 2004 Wiley‐Liss, Inc.
Phylogenetic analysis of clinical mumps virus isolates from vaccinated and non‐vaccinated patients with mumps during an outbreak, Switzerland 1998–2000
Authors: Utz Silvia , Richard Jean‐Luc , Capaul Selja , Matter Hans C. , Hrisoho Meri Gorgievski , Mühlemann Kathrin
Published: March 2004

During the past decade mumps outbreaks have occurred in several European countries with universal vaccination programs probably due to poor efficacy of the Rubini vaccine strain. However, the evolution of vaccine escape mutants has also been considered. A phylogenetic analysis was undertaken on 69 clinical mumps isolates obtained from 39 vaccinated and 22 non‐vaccinated mumps cases (and six cases with unknown vaccination status) during an outbreak in 1998–2000. Two major strain clusters (SWI‐H, SWI‐C) with two subgroups each (SWI‐H1/2, SWI‐C1/2) were identified, which belonged to genotypes C and H. No association between viral clusters and vaccination status or a specific vaccine strain (Jeryl‐Lynn or Rubini) was found. Cluster SWI‐C1 occurred more frequently in the Western part of Switzerland (P < 0.001). Isolates causing complicated disease tended to cluster more frequently with SWI‐H1 (P = 0.11). Wild‐type strains homologous or similar to the Rubini vaccine strain (isolated in Switzerland in 1974) were no longer circulating. Therefore, there was no evidence for vaccine escape mutants. Strain redistribution may have occurred during the past decades. Continuous monitoring of circulating mumps virus populations is needed. J. Med. Virol. 73:91–96, 2004. © 2004 Wiley‐Liss, Inc.
Molecular epidemiology of mumps virus in Japan and proposal of two new genotypes
Authors: Inou Yoko , Nakayama Tetsuo , Yoshida Naoko , Uejima Hajime , Yuri Kenji , Kamada Makoto , Kumagai Takuji , Sakiyama Hiroshi , Miyata Akiko , Ochiai Hitoshi , Ihara Toshiaki , Okafuji Teruo , Okafuji Takao , Nagai Takao , Suzuki Eitaro , Shimomura Kunihisa , Ito Yuhei , Miyazaki Chiaki
Published: March 2004

We isolated 872 strains of mumps virus from naso‐pharyngeal secretions in seven different districts of Japan from January 2000 to July 2001. Among them, 57 strains were geno‐typed by nucleotide sequencing in part of the hemagglutinin‐neuraminidase (HN) and small hydrophobic (SH) protein regions. Four different genotypes (B, G, K, and L) of mumps virus were co‐circulating in Japan and the distribution of genotypes varied in geographically different districts. Two new clusters designated as genotypes K and L had more than 7% nucleotide variation in the SH gene. Among the 57 strains, 11 were classified as B, 35 as G, three as K, and eight as L, which was mainly isolated in Tokyo. We also examined 104 stains isolated in a clinic in Mie prefecture from 1993 to 2003. Genotype B was the indigenous strain and genotype K was introduced in 1994. Genotypes B and K co‐circulated in the 1990s and were replaced by genotype G in 2000. There was no significant change in neutralizing test antibody titers against genotypes B, G, K, and L using seven post‐vaccination sera with Hoshino strain (genotype B) and these four genotypes had a different antigenicity from genotype A. We should continue to watch on mumps virus molecular epidemiology. J. Med. Virol. 73:97–104, 2004. © 2004 Wiley‐Liss, Inc.
Prevalence of viral infection markers by polymerase chain reaction amplification and interferon‐alpha measurements among patients undergoing lumbar puncture in an emergency department
Authors: Hausfater Pierre , Fillet Anne‐Marie , Rozenberg Flore , Arthaud Martine , Trystram David , Huraux Jean‐Marie , Lebon Pierre , Riou Bruno
Published: March 2004

Aseptic meningitis is a frequent diagnosis in emergency departments. Nevertheless, viral investigations are not carried out currently and the viral etiology in adult population has not been studied extensively. We conducted a prospective study including all consecutive patients undergoing lumbar puncture during a 15 months period in an adult emergency department. Bloody and purulent cerebrospinal fluid (CSF) were excluded. The main tests undertaken were: CSF genomic amplification by the polymerase chain reaction (PCR) for neurotropic viruses and serum and CSF interferon‐alpha (IFN‐α) measurements. Among 194 patients included, 45 had and 149 did not have aseptic meningitis. Of 45 patients with aseptic meningitis, 10 had alternative non‐virological final diagnosis, and 35/45 were presumed to have neurological disorders of viral origin. Patients (27/35) completed virological analysis: 21/27 (78%) had either positive viral PCR (enterovirus: 8 patients, Varicella zoster virus (VZV): 5, Epstein‐Barr virus (EBV): 2, herpes simplex virus (HSV): 1, human herpes virus 6: 1) or only raised serum or CSF IFN‐α (4 patients). Overall, 59% of patients with a positive viral PCR had either CSF or serum raised IFN‐α. Twentyone patients without meningitis had either positive viral PCR (enterovirus: 3 patients) or only high serum IFN‐α level (18 patients). In the setting of aseptic meningitis diagnosed in an adult emergency department, viruses are the most common agents encountered, with enterovirus and VZV as the two main etiological agents. Current CSF viral genome amplification and IFN‐α measurement are informative and could be useful to confirm the viral origin of various neurological disorders, although the sensitivity and specificity of IFN‐α measurement for the diagnosis of viral infection need further confirmation. J. Med. Virol. 73:137–146, 2004. © 2004 Wiley‐Liss, Inc.
In situ Raman spectra of an NAD+‐modified silver electrode at various potentials
Authors: Yang Haifeng , Zhang Zongrang , Shen Guoli , Yu Ruqin
Published: March 2004

At various potentials, the in situ confocal Raman technique was employed to detect SERS signals from a silver electrode surface modified with NAD+ through a self‐assembled monolayer (SAM) method. The SERS bands of the NAD+ molecule are much more sensitive to changes in the applied potential compared with experimental results reported previously. It is demonstrated in detail that the NAD+ molecules undergo reorientation at or desorption from the silver electrode surface with a potential shift from −0.5 to 0.0 V vs a saturated calomel electrode based on a charge‐transfer mechanism for explanation of the SERS signals. The effect of buffer electrolytes on the results of the SERS experiment was also investigated. Copyright © 2004 John Wiley & Sons, Ltd.
Single‐crystal Raman study of erythrite, Co3(AsO4)2·8H2O
Authors: Martens Wayde N. , Theo Kloprogge J. , Frost Ray L. , Rintoul Llew
Published: March 2004

Single‐crystal Raman and infrared spectra of natural and synthetic erythrite, Co3(AsO4)2·8H2O, are reported and compared with the spectra polycrystalline, synthetic annabergite, Ni3(AsO4)2·8H2O, and hörnesite, Mg3(AsO4)2·8H2O. Factor group analysis and single‐crystal considerations were used to interpret the experimental data. The Raman spectra of erythrite reveal the ν1 arsenate stretching vibration at 850 cm−1 (Ag) with the corresponding infrared band at 821 cm−1 (Bu). The ν3 antisymmetric vibration is split into three components, observed at 796 (Ag), 788 (Ag) and 803 (Bg) cm−1. The ν2 symmetric bending modes are observed at 375 (Ag) and 385 (Bg) cm−1. The ν4 bending modes are predicted to split into three bands which are observed at 441 (Ag), 446 (Bg) and 457 (Ag) cm−1. Lattice vibrations are found at 112 (Ag), 124 (Bg), 145 (Ag), 157 (Bg), 165 (Ag), 179 (Ag), 189 (Ag), 191 (Bg), 201 (Bg), 210 (Ag), 227 (Ag), 250 (Ag), 264 (Ag), 264 (Ag), 280 (Bg), 302 (Bg), 321 (Bg) and 338 cm−1(Ag). Hydroxyl stretching modes are observed at 3050, 3218, 3333, 3449 and 3479 cm−1 in the infrared spectrum. Raman‐active hydroxyl bands are detected at 3009 (Bg), 3052 (Ag), 3190 (Bg) 3203 (Bg), 3281 (Ag) and 3310 (Bg), 3436 (Bg) and 3443 (Ag) cm−1. Infrared hydroxyl bands at 3050 and 3218 cm−1 are from water type II, short hydrogen bonding distances, and the bands at 3449 and 3479 cm−1 are due to water I, long hydrogen bonding distances. Water bending modes are detected in the infrared spectrum at 1571, 1621, 1641 and 1682 cm−1, but owing to the inherent weak Raman scattering cross‐section of water these could not be detected in the Raman spectra. Copyright © 2004 John Wiley & Sons, Ltd.
Raman spectra of L‐histidine hydrochloride monohydrate crystal
Authors: Faria J. L. B. , Almeida F. M. , Pilla O. , Rossi F. , Sasaki J. M. , Melo F. E. A. , Mendes Filho J. , Freire P. T. C.
Published: March 2004

Single‐crystal samples of L‐histidine hydrochloride monohydrate (LHICL), C6H9N3O2·HCl·H2O, were studied by Raman spectroscopy at temperatures ranging from 295 to 40 K over the spectral range 20–3400 cm−1. A tentative assignment of the bands is given. The effect of temperature change on the vibrational spectrum is discussed. The behavior of the Raman spectra, in particular the emergence of new modes in the low‐wavenumber region, indicates that LHICL undergoes a structural phase transition between 140 and 110 K. There are further indications that, possibly, a second change of structure occurs for temperatures between 80 and 60 K. Copyright © 2004 John Wiley & Sons, Ltd.
Identification of organic particles via Raman techniques after capture in hypervelocity impacts on aerogel
Authors: Burchell M. J. , Creighton J. A. , Kearsley A. T.
Published: March 2004

Capture of small (micrometre‐scale) particles in space occurs at high speeds (typically greater than a few km s−1) and impacts at such speeds usually vaporize the projectile. However, impact on a porous, low‐density medium such as aerogel is not so disruptive and thus the incident particle may be captured relatively intact, even at speeds of 5–6 km s−1. Analysis and subsequent handling of captured particles require great care, and an in situ technique is required for rapid characterization of the particles. Previously it has been shown that Raman techniques can be used for identifying silicate and oxide mineral grains captured in this fashion. Here it is shown that this is also true for organic materials. Particles of poly(methyl methacrylate) and poly(ethyl methacrylate) were fired into aerogel (density 60 km m−3) at speeds of ∼5 km s−1. The Raman spectra obtained from raw grains are comparable to those obtained in situ from grains captured in aerogel. This shows chemically that these organic particles survive the impact process, and that this technique can be used to identify at least some types of organic materials captured in aerogel at high speeds. Copyright © 2004 John Wiley & Sons, Ltd.
Results‐fueled leadership development
Authors: Schaffer Robert H.
Published: March 2004

There is no way to simulate the experience of struggling to achieve a tough goal and succeeding.
Powerful leadership communication
Authors: Baldoni John
Published: March 2004

Effective communication is grounded in the character, conviction, and personal example of the leader.
Zombie businesses: How to learn from their mistakes
Authors: Finkelstein Sydney
Published: March 2004

Organizations that exude self‐confidence, pride, and unrelenting team spirit can become
delusional.
Successful innovation through artful process
Authors: Austin Rob , Devin Lee
Published: March 2004

Learning from collaborative artists in managing knowledge work.
Multiple‐contact adsorption of target molecules by heteropolymer gels†
Authors: Ito Kenji , Chuang Jeffrey , Alvarez‐Lorenzo Carmen , Watanabe Tsuyoshi , Ando Nozomi , Grosberg Alexander Yu.
Published: March 2004

We examined adsorption of target molecules through a multiple‐contact interaction in a thermo‐sensitive heteropolymer gel which can undergo a volume transition at 34°C in water. Multi‐valent anionic target molecules were adsorbed electrostatically by monovalent cationic adsorbing sites in the gel. The overall affinity (SK) between the gel and the target molecule was calculated from the initial slope of the Langmuir adsorption isotherm: [Tads] = KS[Tsol]/(1 + K[Tsol]), where S, K, [Tsol] and [Tads] represent the number of adsorption sites per unit volume of the gel, the effective binding constant, the equilibrium target concentration in the external solution, and the target concentration adsorbed in the gel, respectively. The affinity for the collapsed gel at 60°C was studied in terms of the concentrations of three factors: the adsorber ([Ad]), the coexistent salt (replacement ion, [Re]), and the cross‐linker ([Xl]). We found that the relationship between the affinity and these factors can be summarized by the following formula first suggested by T. Tanaka:

Here c is a constant and p is the number of the contact points between the adsorber units and the target molecule.
Mechanical and dielectric studies of carrageenan sols and gels
Authors: Takemasa Makoto , Chiba Akio , Date Munehiro
Published: March 2004

The temperature dependence of the dynamic shear modulus, strain optical coefficient, DC conductivity, and complex dielectric spectrum of κ‐ and ι‐carrageenan aqueous solutions with K, Ca, Cs, and Na were measured in order to clarify the formation process of the cross‐linking region and the gel network structure. From the correlation analysis between the shear modulus and the strain optical coefficient, we found that the stress inducing unit orientation increases with decreasing temperature, which strongly suggests that the branching number in a cross‐linking region increases with decreasing temperature, which depends on counterion species. In terms of the correlation parameters, an increasing scheme of the branching number depends on counterion species. Just below the coil‐helix transition temperature, dielectric relaxation arises, with relaxation time ∼100μs and relaxation strength ∼103. Dielectric relaxation can be assigned to the counterion fluctuation in the parallel direction to the helical axis. The fluctuation distance of the counterion estimated from the relaxation time increases sharply in the initial stage of gelation and gradually reaches a constant value. We concluded that the longitudinal length of the aggregated region increases sharply at the initial state of gelation while the number of helical molecules bundled in a cross‐linking region increases successively with decreasing temperature.
Deuterium substitution and fluorescence studies on polymer hydrogels and complexes
Authors: Shirota Hideaki , Horie Kazuyuki
Published: March 2004

Deuterium isotope effects on swelling kinetics and volume phase transition in typical polymer hydrogels (poly(N‐isopropylacrylamide) and polyacrylamide gels) are discussed. Deuterium substitutions affect on the swelling kinetics and volume phase transition of the polymer hydrogels. The slower swelling kinetics of hydrogels in D2O than in H2O arises mainly from the high viscosity of the medium. The deuterium isotope effect on the swelling‐shrinking curve of hydrogels would come from the different polymer‐solvent interaction. The microenvironments of hydrogels studied by solvatochromic fluorescence probe are compared with the bulk state. The zipper‐type hydrogen‐bonding inter‐polymer complexes (poly(acrylic acid)‐polyacrylamide and poly(acrylic acid)‐poly(N‐acryloylglycineamide)) are also investigated and show the huge isotope effect on the phase separation temperature.
Copolymers of N‐alkylacrylamides as thermosensitive hydrogels
Authors: Zhu X.X. , Avoce D. , Liu H.Y. , Benrebouh A.
Published: March 2004

Many of the N‐alkyl substituted acrylamide polymers can manifest a lower critical solution temperature (LCST) in aqueous solutions. The LCST of such polymers can be easily varied by a free radical copolymerization of the appropriate comonomers. Natural compounds such as bile acids can be introduced into such polymers to modify the LCST and aggregation behavior and to render the material both thermo‐ and pH‐sensitivity.
Temperature‐responsive, polymer‐modified surfaces for green chromatography
Authors: Kikuchi Akihiko , Okano Teruo
Published: March 2004

Thermoresponsive poly(N‐isopropylacrylamide) (PIPAAm) and its derivatives were utilized as chromatography column matrix modifiers to develop novel supports for thermoresponsive hydrophobic chromatography with aqueous mobile phase. In the column, matrix surfaces show thermoresponsive hydrophilic/hydrophobic property alterations, which alter interaction with and retention of solutes to be separated. We have also demonstrated that the electrostatic interaction of ionic solutes and charged, thermoresponsive polymer‐modified surfaces can be modulated temperature changes in the aqueous mobile phase alone.
Formation of a charge distribution within ionic gels by immobilized enzyme reaction: experimental observations and mathematical simulations
Authors: Ogawa Kazuyoshi , Kokufuta Etsuo
Published: March 2004

Thermally responsive cationic gels with immobilized urease, in the shape of a small cylinder with diameter 290 ‐ 640 μm, were prepared via gelation of an aqueous monomer solution containing the enzyme. We used N‐isopropylacrylamide and N‐vinylimidazole as a thermo‐sensitive and a pH‐sensitive monomer, respectively. Diameters at different positions of the cylinder were microscopically measured in a cell through which substrate solution (pH 4; 35°C) was passed at a constant flow rate; thus, both substrate concentration and pH at the gel surface were maintained at a constant level. It was found that the gel undergoes a shrinking change due to an enzymatically induced increase in pH within the gel phase. There was a marked position dependence of the shrinking degree; the diameter at the center of the cylinder was smaller than those at the top and at the bottom, but the diameters at the top and bottom were identical with each other. This trend was observed at immobilized enzyme concentrations < 1 mg/mL, even after the establishment of swelling equilibrium. By mathematical simulations with a reaction‐diffusion model, these results were understood in connection with a charge distribution which is formed as a result of an enzymatically generated pH gradient within the gel phase.
High response smart gels: synthesis and application
Authors: Arndt Karl‐Fr. , Schmidt Thomas , Richter Andreas , Kuckling Dirk
Published: March 2004

Stimuli‐responsive hydrogels change their volume and elasticity in dependence on the properties of the liquid phase. The amount of solvent uptake is dependent upon the chemical nature of the gel and the nature of its environment, e.g. solvent composition, temperature, pH, etc. The swelling/deswelling process is time consuming. For many applications the response time must be short. According to Tanaka's equation the rate of equilibration is inversely proportional to the square of gel size and proportional to the mutual (or cooperative) diffusion of the network and the solvent. Dcoop is determined by the properties of the cross‐linked polymer and can not be changed for a given chemical system. By decreasing the characteristic dimension of the gel, it is possible to reduce the time for equilibration. The synthesis, characterization of thin layers and small particles of T‐sensitive polymers and their application in a micro‐valve is described.
Risks of allogeneic hand transplantation
Authors: Baumeister Steffen , Kleist Christian , Döhler Bernd , Bickert Bertold , Germann Günter , Opelz Gerhard
Published: March 2004

A patient undergoing allogeneic hand transplantation needs lifelong immunosuppression with the risk of serious side effects, including life‐threatening disease. The question remains: does the eventual improvement in function justify the risk? To answer this question, we try to assess the risks based on a large body of cumulative data derived from more 200,000 kidney transplants using the Collaborative Transplantation Study (CTS). Only selective data which apply to a patient population aged between 15–40 years were used (n = 58,310). Data are compared to the literature references and show superiority with respect to patient numbers, statistics, actuality, and methodology. The CTS data show that the incidence of de novo malignancies is lower than previously reported. The risk of developing any form of cancer is approximately 3%, of developing a skin cancer 1.1%, and of developing a lymphoma 0.58% within 5 years after transplantation. The risk of suffering from a cataract is 11% after 5 years, which is also lower than previously reported. Although the incidence of side effects (particularly malignant disease) is likely to be lower than previously thought, the risk‐benefit question must be answered by each hand surgeon for each individual patient. © 2004 Wiley‐Liss, Inc.
Use of a cross‐over arteriovenous fistula for simultaneous microsurgical tissue transfer and restoration of blood flow to the lower extremity
Authors: Brüner Simone , Jester Andrea , Sauerbier Michael , Germann Günter
Published: March 2004

A new microsurgical concept for simultaneous restoration of peripheral perfusion in the lower extremity and microsurgical free‐tissue transfer is presented. The concept consists of a contralateral cross‐over suprapubic arteriovenous (A‐V) fistula, end‐to‐side anastomoses of the superficial and deep femoral artery to the A‐V fistula, and microsurgical flap transfer after division of the A‐V loop. With this concept, simultaneous restoration of perfusion and defect reconstruction were facilitated. © 2004 Wiley‐Liss, Inc.
Late‐phase ischemic preconditioning in skeletal muscle: is the phenomenon protective?
Authors: Quan Edwin E. , Ramirez Santiago , Tecimer Taskin , Grossi Federico V. , Barker John H. , Maldonado Claudio
Published: March 2004

Reports in the literature on the effectiveness of late‐phase Ischemic preconditioning (IPC) in skeletal muscle are controversial. The purpose of this study was to determine in the same muscle flap model the effectiveness of various IPC protocols in inducing late‐phase protection. Rat latissimus dorsi muscle (LDM) flaps were preconditioned with either 30 or 60 min of total ischemia, divided as follows: single cycles of either 30 or 60 min, two cycles of 15 or 30 min, and three cycles of 10 or 20 min. Ischemia cycles were separated by 10 min of reperfusion. A day after IPC, flaps were elevated and challenged with 4 h of ischemia. Three days later, flaps were assessed for viability. We found that IPC protocols of different total durations and comprised of two or three cycles of ischemia elicited a protective effect against necrosis. We conclude that IPC induces late‐phase protection against necrosis in skeletal muscle, and that the protection requires more than one ischemia/reperfusion cycle. © 2004 Wiley‐Liss, Inc.
Clinical application of the retrograde arterialized venous flap
Authors: Koch Horst , Scharnagl Erwin , Schwarzl Franz X. , Haas Franz M. , Hubmer Martin , Moshammer Harald E.T.
Published: March 2004

Retrograde arterialized venous flaps were applied to skin and soft‐tissue defects in 13 patients with an average age of 34.4 years. Ten defects were located on the hand, and three on the lower leg. All flaps were harvested from the flexor aspect of the forearm; they ranged in size from 2 × 1 to 11 × 7 cm. There was venous congestion with superficial epidermolysis in six flaps, but not in the other seven. Partial skin necrosis in two of the lower‐extremity flaps necessitated secondary skin grafts. Our results suggest that retrograde perfusion enhances blood flow in the periphery of arterialized venous flaps and gives good results in terms of flap survival, especially on the upper extremity. © 2004 Wiley‐Liss, Inc.
Electrophysiologic study of influence on C7 innervated muscles after transection of different C7 fascicles
Authors: Xu Jian‐Guang , Gu Yu‐Dong , Hu Shao‐Nan , Wang Huan , Chen Liang
Published: March 2004

An experimental study was conducted to observe the electrophysiologic changes in C7 innervated muscles following transection of different fascicles of C7 nerve root in the brachial plexus with already transected C5 and C6. Twenty‐four Sprague‐Dawley rats were randomized into groups A, B, and C. C5 and C6 transection, C5, C6, and partial C7 (anteriolateral fascicles of the anterior division) transection, and C5, C6, and C7 transection were done in group A, B, and C, respectively. One month postoperatively, compound muscle action potentials of the latissimus dorsi, triceps, and extensor digitorum communis were recorded. Decreased amplitude and a prolonged latent period were seen in all three muscles of group C. No obvious changes, however, were found in groups A and B. This suggests that when the upper trunk of the brachial plexus is injured, partial transection of C7 does not obviously impair C7 innervated muscle function. Selective ipsilateral C7 transfer is safe for the treatment of upper‐trunk avulsion. © 2004 Wiley‐Liss, Inc.
Broadband circularly polarized printed‐spiral‐strip antenna for 5‐GHz WLAN operation
Authors: Su Che‐Wei , Liu Yung‐Tao , Chen Wen‐Shyang , Cheng Yuan‐Tung , Wong Kin‐Lu
Published: March 2004

A novel broadband circularly polarized printed‐spiral‐strip antenna is presented. The antenna consists of a printed spiral strip of about 1.4 wavelengths in length wound into about one turn and mounted above a ground plane with a thick air layer. By using a 50Ω probe feed along with a long feeding strip and a coupled long‐shorting strip for exciting the printed spiral strip, good circular polarization (CP) radiation over a wide bandwidth (larger than 20%) is achieved, which makes the proposed antenna well suited for applications in the 5‐GHz WLAN band. Details of the proposed antenna design and the experimental results obtained for a constructed prototype are presented. © 2004 Wiley Periodicals, Inc. Microwave Opt Technol Lett 41: 163–165, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.20080
Novel antennas for ultra‐wideband communications
Authors: Fortino N. , Kossiavas G. , Dauvignac J. Y. , Staraj R.
Published: March 2004

Two novel antennas for UWB communications, both inspired from bowtie and triangular patch structures, are presented and tested. This paper proposes their study and optimization in order to cover the new WPAN standard and facilitate their integration on communication devices. This work has then been centered around three specific goals: wide bandwidth, minimum size, and low cost. © 2004 Wiley Periodicals, Inc. Microwave Opt Technol Lett 41: 166–169, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.20082
A multi‐wideband microstrip antenna designed by the square‐curve fractal technique
Authors: Siakavara K. , Tsaldaris F.
Published: March 2004

A novel microstrip antenna is synthesized by the square‐curve fractal algorithm. The generator element is a rectangular microstrip ring and the antenna realizes multiband operation. This performance can also be achieved by using other fractal algorithms found in the literature. However, in all cases the frequency bandwidth is very narrow. In the present work, bandwidths up to 12% are achieved by the use of double feed and one pin. The antenna's additional figure of merit is its ability to be driven only by probes and without the need of any matching circuit. © 2004 Wiley Periodicals, Inc. Microwave Opt Technol Lett 41: 180–185, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.20086
Analysis of RF scattering parameters and noise and power performances of RF‐power MOS in 0.15‐μm RF cmos technology for RF SOC applications
Authors: Lin Yo‐Sheng
Published: March 2004

In this paper, we demonstrate an analysis of the effects of transconductancegmon the kink phenomenon of the scattering parametersS11,S22,S21, andS12of RF powern‐MOSFETs in 0.15‐μm RF CMOS technology for RF SOC applications. It is found that either the increase of the device's width or the increase of the gate‐source voltageVGS(when its correspondinggmis smaller than the maximumgm) and the decrease of the measurement temperature can enhance the kink effect of bothS11andS22due to the increase ofgm. The anomalous dip in theS11andS22of RF powern‐MOSFETs can also be interpreted in terms of poles and zeros. In addition, we conclude that a device with larger gate width or largergmexhibits better RF noise and power performances because of higher gain (orgm) and the lighter effect of the parasitic extrinsic elements. The present analyses enable RF engineers to understand more deeply the behaviors ofSparameters, RF noise and power performances of RF power MOSFETs, and hence is helpful for them to create a fully scalable wideband RF‐power MOS or CMOS model for RF SOC applications. © 2004 Wiley Periodicals, Inc. Microwave Opt Technol Lett 41: 191–196, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.20089
A CPW‐fed broadband slot antenna with linear taper
Authors: Niu Jun‐Wei , Zhong Shun‐Shi
Published: March 2004

A new coplanar waveguide (CPW)‐fed broadband printed slot antenna is presented. The impedance bandwidth is greatly increased by using a linear taper. The test antenna's impedance bandwidth of −10‐dB return loss reaches 40% with low cross‐polarization level. The impedance characteristics and radiation patterns of the slot antenna with different sizes of tapers are presented. The simulated results agree well with the measured ones. © 2004 Wiley Periodicals, Inc. Microwave Opt Technol Lett 41: 218–221, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.20098
Planar‐fed compact circular‐polarised microstrip antenna with triangular‐slot loading
Authors: Elsdon M. , Sambell A. , Gao S. C. , Qin Y.
Published: March 2004

A planar‐fed circular‐polarised (CP) microstrip patch antenna is presented and discussed. It is demonstrated that embedding four right‐angle triangular slots in a nearly square patch antenna and exciting with an offset inset feed, size reduction of up to 43% can be achieved while still maintaining planar impedance matching. The proposed design shows no significant reduction in the axial‐ratio bandwidth and has relaxed manufacturing tolerances. © 2004 Wiley Periodicals, Inc. Microwave Opt Technol Lett 41: 226–228, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.20100
Stability and noise performance of resistively loaded microwave amplifiers
Authors: Post John E.
Published: March 2004

Resistive loading is a classic technique to guarantee the unconditional stability of microwave amplifiers at the operating frequency, but the amplifier is potentially unstable at other frequencies. A technique is proposed to predict microwave amplifier stability at all frequencies by solving for the stability parameter of the overall cascaded resistor/transistor network. Eight different stabilizing networks are investigated and shown to have very different stabilizing effects as a function of frequency. A method to determine the effect of resistive stabilization on amplifier‐noise performance is presented. These results allow the designer to choose a stabilizing resistor network that provides the best compromise between gain, noise, and stability for a desired application. © 2004 Wiley Periodicals, Inc. Microwave Opt Technol Lett 41: 228–231, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.20101
Decrease of sidelobe energy by shifts in original training images for synthetic aperture radar image recognition
Authors: Chen Chewei , Chen Chulung
Published: March 2004

For synthetic aperture radar (SAR) image recognition, correlation filters were designed in our previous research by the nonzero‐ order joint‐transform correlator. Training images were placed at the presumed center in order to synthesize the reference function. However, this could not guarantee that the average cross correlation energy would be minimum. To improve this, training images are shifted pixel by pixel from left to right and top to bottom in this study. We synthesize the reference functions, hoping to find lower cross‐correlation energy. Finally, we obtain sharper correlation peaks and less sidelobe energy, which can increase the recognition ability. © 2004 Wiley Periodicals, Inc. Microwave Opt Technol Lett 41: 241–244, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.20105
Optimization of parthenogenetic activation protocol in porcine
Authors: Lee Jang‐Won , Tian X. Cindy , Yang Xiangzhong
Published: March 2004

The effects of the electrical field strengths, number of pulses, and post‐activation media on chromatin conformation and parthenogenetic development were studied to optimize the activation protocol for porcine nuclear transfer. In experiment 1, electrical field strengths were examined. Oocytes were subjected to square direct current pulses at output voltages of 1.2, 1.7, 2.2, and 2.7 kV/cm for 1 × 30 μsec. The voltage resulting from experiment 1 was 2.2 kV/cm, in which 50.0% of activated oocytes developed to blastocysts in vitro. In experiment 2, the influence of 1, 2, and 3 pulses on blastocyst development was tested using field strengths and post‐activation medium described in experiment 1. Oocytes activated by a single 30 μsec pulse of 2.2 kV/cm DC yielded a higher blastocyst rate (56.3%) than oocytes activated by 2 or 3 pulses (<42.5%). In experiment 3 and 4, we investigated the effects of cytochalasin B (CB), cycloheximide (CH), and CB + CH on nuclear development stages and parthenogenetic development following a single 30 μsec pulse of 2.2 kV/cm DC. The percentage of activated oocytes was not different among CB (93.3%), CB + CH (98.3%), control (80.0%), and CH (80.0%) groups 12 hr after activation. Treatment with CB (57.5%) or CB + CH (53.8%) enhanced the blastocyst rate compared with other groups, CH (23.8%) treated‐ and control group (18.8%). The results demonstrated that a single 30 μsec pulse of 2.2 kV/cm DC followed by culturing in post‐activation medium with CB for 5 hr were effective parameters for parthenogenetic activation and blastocyst formation of in vitro matured porcine oocytes which suggests that a single calcium rise is sufficient to activate pig oocytes and to achieve high rate of blastocyst development. Mol. Reprod. Dev. 68: 51–57, 2004. © 2004 Wiley‐Liss, Inc.
Specific gene silencing in the pre‐implantation stage mouse embryo by an siRNA expression vector system
Authors: Haraguchi Seiki , Saga Yumiko , Naito Kunihiko , Inoue Hirokazu , Seto Akira
Published: March 2004

Recently, small interfering RNAs (siRNAs) have become a powerful and widely used tool for the analysis of gene function in mammalian cells. Here we report that the microinjection of an siRNA expression vector into the nucleus is an efficient and powerful method of specific gene silencing in pre‐implantation mouse embryos. We used this method to examine the expression of two genes EGFP and Oct4. Vectors encoding siRNAs targeted against EGFP or Oct4 were injected into the pronucleus or nucleus of zygotes, which were then cultured until the blastocyst stage. When the effects of RNAi were examined in blastocyst stage eggs, there was robust inhibition of the gene product in a concentration‐dependent manner at both the mRNA and the protein level. The expression of other endogenous genes was not affected, showing the specificity of the vector‐mediated RNAi. In addition, this method was effective for inhibiting maternally expressed mRNA. To demonstrate that RNAi of Oct4 induced a similar phenotype to that of Oct4‐null embryos, the blastocysts were further cultured in ES medium. After the fourth day of culture, the embryos either had outgrown only a layer of trophoblast cells or showed developmental arrest at the blastocyst stage (>90%). Moreover, concomitant with Oct4 suppression at the blastocyst stage, we observed inhibition of Fgf4, a gene that is known to be induced downstream of Oct4 expression. Taken together, these results demonstrate that the use of siRNA expression vector is a powerful way to achieve gene silencing in the pre‐implantation stage embryo. Mol. Reprod. Dev. 68: 17–24, 2004. © 2004 Wiley‐Liss, Inc.
Bovine oocyte cytoplasm supports nuclear remodeling but not reprogramming of murine fibroblast cells
Authors: Park Sang‐Hyun , Shin Mi‐Ra , Kim Nam‐Hyung
Published: March 2004

Nuclear transfer (NT) is used to elucidate fundamental biological issues such as reversibility of cell differentiation and interactions between the cytoplasm and nucleus. To obtain an insight into interactions between the somatic cell nucleus and oocyte cytoplasm, nuclear remodeling and gene expression were compared in bovine oocytes that had received nuclei from bovine and mouse fibroblast cells. While the embryos that received nuclei from bovine fibroblast cells developed into blastocysts, those that received nuclei from mouse fibroblasts did not develop beyond the 8‐cell stage. Similar nuclear remodeling procedures were observed in oocytes reconstructed with mouse and bovine fibroblast cells. Foreign centrosomes during NT were introduced into embryos reconstructed with both fibroblast cell types. A number of housekeeping mouse genes (hsp70, bax, and glt‐1) were abnormally expressed in embryos that had received nuclei from mouse fibroblast cells. However, development‐related genes, such as Oct‐4 and E‐cad, were not expressed. The results collectively suggest that the bovine oocyte cytoplasm supports nuclear remodeling, but not reprogramming of mouse fibroblast cells. Mol. Reprod. Dev. 68: 25–34, 2004. © 2004 Wiley‐Liss, Inc.
Enriched gonadal migration of donor‐derived gonadal primordial germ cells by immunomagnetic cell sorting in birds
Authors: Kim Jin Nam , Kim Mi A , Park Tae Sub , Kim Duk Kyung , Park Hyun Jeong , Ono Tamao , Lim Jeong Mook , Han Jae Yong
Published: March 2004

This study was conducted to evaluate whether immunomagnetic treatment could improve the retrieval and migration capacity of avian gonadal primordial germ cells (gPGCs) collected from gonads in 5.5‐day‐old chick and 5‐day‐old quail embryos, respectively. Collected gPGCs were loaded into a magnetic‐activated cell sorter (MACS) after being conjugated with specific gPGC antibodies and either MACS‐treated or non‐treated cells in each species were subsequently transferred to the recipient embryos. MACS treatment significantly (P < 0.05) increased the population ratio of gPGCs in gonadal cells retrieved (0.74 to 33.4% in the chicken and 2.68 to 45.1% in the quail). This was due to decreased number of non‐gPGCs in total cell population. MACS treatment further enhanced gonadal migration of gPGCs transferred in both species (10% vs. 80–85% in the chicken and 10–15% vs. 70–80% in the quail). Increase in the number of microinjected cells up to 600 cells/embryo did not eliminate such promoting effect. In conclusion, MACS treatment greatly increased the population ratio of avian gPGCs in gonadal cells, resulting improved gonadal migration in recipient embryos. Mol. Reprod. Dev. 68: 81–87, 2004. © 2004 Wiley‐Liss, Inc.
Effects of oxidative stress and inhibitors of the pentose phosphate pathway on sexually dimorphic production of IFN‐τ by bovine blastocysts
Authors: Kimura K. , Spate L.D. , Green M.P. , Roberts R.M.
Published: March 2004

Bovine interferon‐tau (IFN‐τ), the anti‐luteolytic factor secreted by conceptuses of pecoran ruminants, is a product of autosomal genes, yet in vitro produced (IVP) female expanded blastocysts (EB) secrete about twice as much IFN‐τ as males. Two possible explanations have been tested here. One is that embryos of one sex are differentially susceptible to oxidative stress. The second is that female EB produce more IFN‐τ because pentose‐phosphate pathway (PPP) activity is elevated as a result of delayed X‐chromosome inactivation. IVP bovine zygotes were cultured to the 8‐cell stage and placed under conditions designed either to promote oxidative stress (±H2O2; 20 vs. 5% O2), or to inhibit glucose 6‐phosphate dehydrogenase (G6PDH) activity (addition of dehydroepiandrosterone, DHEA or 6‐aminonicotinamide, 6‐AN to the medium). At day 8, blastocysts were cultured individually for a further 48 hr to assess IFN‐τ production, and embryo sex determined retrospectively. Blastocyst numbers were reduced (P < 0.05) and their continued development impaired (P < 0.05) in presence of H2O2 (200 μM) and 20% O2, but neither IFN‐τ production nor sexually dimorphic expression of IFN‐τ were affected. IFN‐τ production was reduced, particularly in females (P < 0.05), and sexual dimorphic differences in production were lost in the presence of both DHEA (100 μM) and 6‐AN (1 μM). In the case of 6‐AN, these effects were achieved without a significant decline in blastocyst developmental progression, quality, or cell number. The data suggest that the higher production of IFN‐τ by female EB is an indirect outcome of the increased activity of the oxidative arm of the PPP pathway. Mol. Reprod. Dev. 68: 88–95, 2004. © 2004 Wiley‐Liss, Inc.
Primordial germ cells: what does it take to be alive?
Authors: Tres Laura L. , Rosselot Carolina , Kierszenbaum Abraham L.
Published: March 2004

Specification of primordial germ cells (PGCs) in the proximal epiblast enables about 45 founder PGCs clustered at the base of the allantoic bud to enter the embryo by active cell movement. Specification of the PGC lineage depends on paracrine signals derived from the somatic cell neighbors in the extraembryonic ectoderm. Secretory bone morphogenetic proteins (BMP) 4, BMP8b, and BMP2 and components of the Smad signaling pathway participate in the specification of PGCs. Cells in the extraembryonic ectoderm induce expression of the gene fragilis in the epiblast in the presence of BMP4, targeting competence of PGCs. The fragilis gene encodes a family of transmembrane proteins presumably involved in homotypic cell adhesion. As PGCs migrate throughout the hindgut, they express nanos3 protein. In the absence of nanos3 gene expression, no germ cells are detected in ovary and testis. During migration and upon arrival at the genital ridges, the population of PGCs is regulated by a balanced proliferation/programmed cell death or apoptosis. Paracrine and autocrine mechanisms, involving transforming growth factor‐β1 and fibroblast growth factors exert stimulatory or inhibitory effects on PGCs proliferation, modulated in part by the membrane‐bound form of stem cell factor. Apoptosis requires the participation of the pro‐apoptotic family member Bax, whose activity is balanced by the anti‐apoptotic family member Bcl21/Bcl‐x. In addition, a loss of cell‐cell contacts in vitro results in the apoptotic elimination of PGCs. It needs to be determined whether apoptosis is triggered by a failure of PGC to establish and maintain appropriate cell‐cell contacts with somatic cells or whether undefined survival factors released by adjacent somatic cells cannot reach physiological levels to satisfy needs of the expanding population of PGCs. Mol. Reprod. Dev. 68: 1–4, 2004. © 2004 Wiley‐Liss, Inc.
Strain localization in sand: an overview of the experimental results obtained in Grenoble using stereophotogrammetry
Authors: Desrues Jacques , Viggiani Gioacchino
Published: March 2004

Experimental results are presented from the extensive program of drained plane strain compression tests on sand carried out in Grenoble over the last two decades. Systematic analysis of photographs of the deforming specimen allowed for measuring deformations and determining strain fields throughout the test, that is: prior to, at, and after the onset of strain localization. The principles, details and accuracy of the procedure are described, as well as its suitability to properly depict the patterns of deformation. Findings concerning the occurrence and progression of strain localization are discussed. The issues of shear band orientation and thickness are addressed, as well as temporary and persistent complex localization patterns, and the volumetric behaviour inside a band after its formation. The influence of such variables as initial state of the sand (effective stress and relative density), specimen size and slenderness, as well as grain size, is discussed. Copyright © 2004 John Wiley & Sons, Ltd