bluuebunny/crossref_metadata_2025 huggingface dataset:
Mikroelektrochemie an einzelnen Zellen
Authors: Schulte Albert , Schuhmann Wolfgang
Published: October 2007

Nadelförmige voltammetrische Ultramikroelektroden zeigen eine herausragende Empfindlichkeit bei der Detektion redoxaktiver Substanzen, eine schnelle Ansprechzeit und Gesamtspitzendurchmesser im unteren Mikrometerbereich. Durch diese Charakteristika sind sie ideal für die Analyse der chemischen Umgebung und der Aktivität isolierter lebender Zellen, die in ihren vielfältigen Ausgestaltungen die mikroskopischen Baueinheiten menschlicher, tierischer und weiterer Lebensformen bilden. Voraussetzungen für erfolgreiche lokale elektrochemische Messungen in der Nachbarschaft winziger biologischer Objekte sind eine sanfte, Stress‐freie und akkurate Platzierung der Sondenspitze an der Zelle, eine genaue Kenntnis des Abstandes zwischen Sonde und Zelle und eine hinreichende Selektivität der Ultramikroelektrodenspitze für Substanzen, deren Konzentrationen sich als Folge zellulärer Vorgänge wie Wachstum, Atmung oder Transmitter‐/Metabolitenaufnahme oder ‐abgabe verändern. Die Konzepte der Einzelzellmikroelektrochemie werden vorgestellt, und es wird ein Überblick gegeben über jüngste Ergebnisse zu fundamentalen Mechanismen von Zellfunktionen.
Single‐Cell Microelectrochemistry
Authors: Schulte Albert , Schuhmann Wolfgang
Published: October 2007

Needle‐type voltammetric ultramicroelectrodes show exceptional sensitivity for the detection of redox‐active substances, rapid response times, and total tip diameters in the lower micrometer range. These characteristics make them ideal for analyzing the chemical environment and the activity of isolated living cells, which in their various forms are the microscopic building blocks of human, animal, and other life forms. Prerequisites for successful local electrochemical measurements in the vicinity of the tiny biological objects are gentle, stress‐free, and accurate placement of the tip at the cell, exact knowledge of the tip‐to‐cell distance, and appropriate selectivity of the ultramicroelectrode tip for species that may change in concentration as a result of cellular actions such as growth, respiration, or transmitter and metabolite uptake or release. The concepts of single‐cell microelectrochemistry are considered and an overview is given of recent results on the fundamental mechanisms of cell functions.
Active learning for constructing transliteration lexicons from the Web
Authors: Kuo Jin‐Shea , Li Haizhou , Yang Ying‐Kuei
Published: October 2007

This article presents an adaptive learning framework for Phonetic Similarity Modeling (PSM) that supports the automatic construction of transliteration lexicons. The learning algorithm starts with minimum prior knowledge about machine transliteration and acquires knowledge iteratively from the Web. We study the unsupervised learning and the active learning strategies that minimize human supervision in terms of data labeling. The learning process refines the PSM and constructs a transliteration lexicon at the same time. We evaluate the proposed PSM and its learning algorithm through a series of systematic experiments, which show that the proposed framework is reliably effective on two independent databases.
Randomized controlled trial of adjuvant uracil–tegafur versus surgery alone for serosa-negative, locally advanced gastric cancer
Authors: Nakajima T , Kinoshita T , Nashimoto A , Sairenji M , Yamaguchi T , Sakamoto J , Fujiya T , Inada T , Sasako M , Ohashi Y
Published: October 2007

Background

This prospective randomized study compared the survival of patients with tumour node metastasis (TNM) stage T2 N1–2 gastric cancer treated by gastrectomy alone or gastrectomy followed by uracil–tegafur.

Methods

Patients were randomly assigned to surgery alone or to surgery and postoperative uracil–tegafur 360 mg per m2 per day orally for 16 months. The primary endpoint was overall survival. Relapse-free survival and site of recurrence were secondary endpoints.

Results

Of 190 registered patients, 95 were randomized to each group; two patients with early cancer were subsequently excluded from the chemotherapy group. The trial was terminated before the target number of patients was reached because accrual was slower than expected. Drug-related adverse effects were mild, with no treatment-related deaths. At a median follow-up of 6·2 years, overall and relapse-free survival rates were significantly higher in the chemotherapy group (hazard ratio for overall survival 0·48, P = 0·017; hazard ratio for relapse-free survival 0·44, P = 0·005), confirming the survival benefit shown in an interim analysis performed 2 years earlier.

Conclusion

Interim and final analyses revealed a significant survival benefit for postoperative adjuvant chemotherapy with uracil–tegafur in patients with serosa-negative, node-positive gastric cancer. Registration number: NCT00152243 (http://www.clinicaltrials.gov).
Musculotendinous transfer as a treatment option for irreparable posterosuperior rotator cuff tears: Teres major or latissimus dorsi?
Authors: Buijze G.A. , Keereweer S. , Jennings G. , Vorster W. , Debeer J.
Published: October 2007

Irreparable posterior cuff tears can cause pain and lack of shoulder function. Surgical treatment includes musculotendinous transfers of either latissimus dorsi (LD) or teres major (TM). This study aimed to give a detailed description of the morphology of these two muscles with particular regard to their suitability for use in transfers. Sixty‐two shoulders in 31 cadaveric specimens (mean age 50 years) were dissected. The mean length of the TM was 13.7 cm at its superior edge while the distance from the muscle origin to the greater tuberosity (GT) was 19.2 cm. The tendon of the TM had a length of 1.5 cm, a width of 3.4 cm, and a thickness of 1.3 mm. The mean length of the LD was 26.0 cm and the distance from its origin to the GT was 32.9 cm. The mean length of the LD tendon was 5.2 cm, its width 2.9 cm, and its thickness 1.0 mm. The increased length required to achieve transfer was 47% (of the original length) for TM and 33% for LD. Both TM and LD could reach the GT with ease, according to the potential muscle excursions. Tension of the neurovascular bundle is more probable with LD because it enters the muscle relatively closer to the tendon. Problems with regard to reattachment may be more likely to occur in a transfer of the TM because of its short tendon. Clin. Anat. 20:919–923, 2007. © 2007 Wiley‐Liss, Inc.
Anatomic relationship of heel spur to surrounding soft tissues: Greater variability than previously reported
Authors: Li J. , Muehleman C.
Published: October 2007

The stimulating factor for the development of heel spur (calcaneal exostosis) is controversial. In a sample of elderly cadaveric specimens, using radiographic, gross morphological, and histological investigation, we demonstrate that heel spurs are generally not found in the trajectory of traction from the plantar aponeurosis enthesis or plantar muscles. Rather, they are variably associated with soft tissues including loose connective tissue, fibrocartilage, muscle, and aponeurosis. Furthermore, the bony trabeculae of the spur are not aligned in the direction of soft tissue traction, but rather in the direction of stress on the calcaneus during walking and standing. These results substantiate the view that the heel spur may be a skeletal response to stress and may serve to protect the bone against the development of microfractures. Clin. Anat. 20:950–955, 2007. © 2007 Wiley‐Liss, Inc.
Myoseverin disrupts sarcomeric organization in myocytes: An effect independent of microtubule assembly inhibition
Authors: Ng Dominic C. H. , Gebski Bijanka L. , Grounds Miranda D. , Bogoyevitch Marie A.
Published: October 2007

Although disruption of the microtubule (MT) array inhibits myogenesis in myocytes, the relationship between the assembly of microtubules (MT) and the organization of the contractile filaments is not clearly defined. We now report that the assembly of mature myofibrils in hypertrophic cardiac myocytes is disrupted by myoseverin, a compound previously shown to perturb the MT array in skeletal muscle cells. Myoseverin treated cardiac myocytes showed disruptions of the striated Z‐bands containing α‐actinin and desmin and the localization of tropomyosin, titin and myosin on mature sarcomeric filaments. In contrast, MT depolymerization by nocodazole did not perturb sarcomeric filaments. Similarly, expression of constitutively active stathmin as a non‐chemical molecular method of MT depolymerization did not prevent sarcomere assembly. The extent of MT destabilization by myoseverin and nocodazole were comparable. Thus, the effect of myoseverin on sarcomere assembly was independent of its capacity for MT inhibition. Furthermore, we found that upon removal of myoseverin, sarcomeres reformed in the absence of an intact MT network. Sarcomere formation in cardiac myocytes therefore, does not appear to require an intact MT network and thus we conclude that a functional MT array appears to be dispensable for myofibrillogenesis. Cell Motil. Cytoskeleton 2008. © 2007 Wiley‐Liss, Inc.
The first score predicting overall survival in patients with metastatic spinal cord compression
Authors: Rades Dirk , Dunst Juergen , Schild Steven E.
Published: October 2007

BACKGROUND.

The current study was performed to create a scoring system to estimate the survival of patients with metastatic spinal cord compression (MSCC).

METHODS.

Based on a multivariate survival analysis of 1852 patients who were treated with radiotherapy (RT) for MSCC, a scoring system was developed. The system included the 6 prognostic factors found to be significant in that multivariate analysis: tumor type, interval between tumor diagnosis and MSCC, other bone or visceral metastases at the time of RT, ambulatory status, and duration of motor deficits. The score for each prognostic factor was determined by dividing the 6‐month survival rate (given as the percentage) by 10. The total score represented the sum of the scores for each prognostic factor. Total scores ranged between 20 and 45 points and patients were divided into 5 groups. For each group, the survival was compared for short‐course or long‐course RT.

RESULTS.

The 6‐month survival rates were 4% for patients with a score of 20 to 25 points,11% for patients with a score of 26 to 30 points, 48% for patients with a score of 31 to 35 points, 87% for patients with a score of 36 to 40 points, and 99% for patients with a score of 41 to 45 points (P < .001). Patients with scores ≥36 were found to have a significantly longer survival when comparing long‐course versus short‐course RT, and those with scores <36 were found to have similar survival regardless of whether short‐course or long‐course RT was used.

CONCLUSIONS.

Using the scoring system described herein, patients with MSCC can be grouped to estimate survival. Patients with scores ≥36 were found to survive longer with long‐course RT, whereas patients with lower scores had a similar survival regardless of whether long‐course or short‐course RT was used. Cancer 2008. © 2007 American Cancer Society.
Group II metabotropic glutamate receptors in anxiety circuitry: Correspondence of physiological response and subcellular distribution
Authors: Muly E. Chris , Mania Irakli , Guo Ji‐Dong , Rainnie Donald G.
Published: October 2007

Activation of group II metabotropic glutamate receptors (mGluR2/3) in the amygdala plays a critical role in the regulation of fear and anxiety states. Previous studies using nonselective agonists have suggested this action can result from activation of either pre‐ or postsynaptic mGluR2/3. Here, we have used a combination of whole‐cell patch clamp recording with highly selective agonists (LY354740 and LY379268) and immunoelectron microscopy to examine structure‐function relationships for mGluR2/3 in the basolateral amygdala (BLA) and bed nucleus of the stria terminalis (BNST). Stimulation of mGluR2/3 evoked a direct, TTX‐insensitive membrane hyperpolarization in all BLA projection neurons tested, but only about half of BNST neurons. The membrane hyperpolarization was mediated by activation of an outward potassium current or blockade of a tonically active inward Ih current in different groups of BLA neurons. In both regions, mGluR2/3 caused a long‐lasting reduction of glutamate release from presynaptic afferent terminals even at concentrations that failed to elicit a direct postsynaptic response. The localization of mGluR2/3 differed regionally, with postsynaptic labeling significantly more common in BLA than BNST, corresponding to the strength of postsynaptic responses recorded there. Our results demonstrate a complex role for mGluR2/3 receptors in modulating anxiety circuitry, including direct inhibition and reduction of excitatory drive. The combination of direct inhibition of projection neurons within the BLA and suppression of excitatory neurotransmission in the BNST may be responsible for the anxiolytic actions of group II mGluR agonists. J. Comp. Neurol. 505:682–700, 2007. © 2007 Wiley‐Liss, Inc.
FT‐Grid: a system for achieving fault tolerance in grids
Authors: Xu Jie , Townend Paul , Looker Nik , Groth Paul
Published: October 2007

The FT‐Grid system introduces a fault‐tolerance framework that allows faults occurring in service‐oriented systems to be tolerated, thus increasing the dependability of such systems. This paper presents the design, development and evaluation of FT‐Grid. We show empirical evidence of the dependability benefits offered by FT‐Grid by performing an experimental dependability analysis using fault‐injection testing performed with the WS‐FIT tool. We then illustrate a potential problem with voting‐based fault‐tolerance schemes in the service‐oriented paradigm—namely that individual channels within a fault‐tolerant system, supposed to be independent of each other, may in fact invoke common services as part of their workflow, thus increasing the potential for common‐mode failure of those channels. We propose a solution to this issue by using the technique of provenance to provide FT‐Grid with topological awareness. We implement a large experimental system, and—with the use of the Provenance Recording for Services system developed as part of the PASOA project at the University of Southampton—perform a large number of experiments that show that a topologically aware FT‐Grid system serves as a much more dependable system than any other configuration tested, while imposing a negligible timing overhead. Copyright © 2007 John Wiley & Sons, Ltd.
Optical investigations on the existence of phase transition in ZnO:Li thin films prepared by DC sputtering method
Authors: Abu EL‐Fadl A. , EL‐Maghraby E. M. , Yamazaki T.
Published: October 2007

We investigated the effect of temperature on the absorption spectra of Zn0.8Li0.2O thin films (ZnO:Li), deposited at 573 K, in the wavelength range 190‐800 nm. The films were deposited on sapphire, MgO or quartz substrates by DC sputtering method. The results show a shift of the optical energy gap (Eg), with direct allowed transition type near the fundamental edge, to lower wavelengths as the temperature increases. The temperature rate of Eg changes considerably showing an anomaly around 320 K depending on type of substrate. The founded results indicated that replacement of Zn ions with Li ions induces a ferroelectric phase in the ZnO wurtzite‐type semiconductor. The exponential dependence of the absorption coefficient on the incident photon energy suggests the validity of the Urbach rule. (© 2007 WILEY ‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Growth rate of single acetaminophen crystals in supersaturated aqueous solution under different operating conditions
Authors: Omar W. , Al‐Sayed S. , Sultan A. , Ulrich J.
Published: October 2007

Single crystal growth experiments were conducted to investigate the growth rate of acetaminophen (paracetamol) crystals under carefully controlled conditions of temperature, supersaturation and pH value. The relative growth rate of the different faces was studied. Growth Rate Dispersion (GRD) was observed by studying the effect of supersaturation and temperature on the growth rate. The growth rate in all directions was found to be temperature dependant. Elongation of the crystals was measured due to the faster growth in the Y‐ direction and Xa direction compared to in the Xb direction. Dissolution of the crystals was observed at pH values greater than 8.5, and a growth rate retardation was observed when increasing the pH from 5.6, which is the normal value without additions, to higher values in both acidic and basic mediums up to 8.5. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Optimization of flow cytometric measurement of ZAP‐70 in chronic lymphocytic leukemia
Authors: Preobrazhensky Sergey N. , Bahler David W.
Published: October 2007

Background

The goal of this study was to optimize a cell staining procedure for flow cytometric detection of zeta‐chain associated protein‐70 (ZAP‐70). Our specific objectives were to improve antibody selection criteria, identify a cell permeabilization procedure better tailored to ZAP‐70 analysis, as well as to establish objective criteria to control antigen stability.

Methods

Sequentially titrated 2F3.2‐FITC, 1E7.2‐FITC, and 1E7.2‐Alexa Fluor 488 anti‐ZAP‐70 antibodies were used to stain normal B and T cells and Scatchard analysis was applied to calculate Kd and Bmax values from saturation curves of specific binding. ZAP‐70 staining was compared in cells permeabilized with two commercially available kits, Triton X‐100, and a custom saponin procedure.

Results

Normal B‐cells were found to provide an excellent measure of nonspecific staining while varying ZAP‐70 antibodies and concentrations. Comparing Scatchard analyses of specific T‐cell binding revealed that 1E7.2‐Alexa Fluor 488 had the highest binding affinity of the tested anti‐ZAP‐70 antibodies and was the best choice. The highest levels of ZAP‐70 fluorescence occurred when cells were permeabilized using a noncommercial saponin procedure. Decrease of chronic lymphocytic leukemia cell viability correlated with diminished ZAP‐70 expression; when viability was lower than 95% the percentage of bright positive samples was significantly decreased, indicating a possibility of false‐negative results.

Conclusions

The efficiency and reliability of flow cytometric detection of ZAP‐70 can be optimized by using Scatchard analysis to help select the most effective antibodies and antibody concentrations that maximize specific to nonspecific binding, by using a “custom” ZAP‐70 permeabilization procedure, and by better controlling antigen stability by measuring cell viability. © 2007 Clinical Cytometry Society.
Ongoing sonic hedgehog signaling is required for dorsal midline formation in the developing forebrain
Authors: Hayhurst Monica , Gore Bryan B. , Tessier‐Lavigne Marc , McConnell Susan K.
Published: October 2007

The division of the mammalian forebrain into distinct left and right hemispheres represents a critical step in neural development. Several signaling molecules including sonic hedgehog (SHH), fibroblast growth factor 8 (FGF8), and bone morphogenetic proteins (BMPs) have been implicated in dorsal midline development, and prior work suggests that the organizing centers from which these proteins are secreted mutually regulate one another during development. To explore the role of the ventral organizing center in the formation of two hemispheres, we assessed dorsal midline development in Shh mutant embryos and in wildtype embryos treated with the SHH signaling inhibitor HhAntag. Collectively, our findings demonstrate that SHH signaling plays an important role in maintaining the normal expression patterns of Fgf8 and Bmp4 in the developing forebrain. We further show that FGF8 can induce the expression of Zic2, which is normally expressed at the midline and is required in vivo for hemispheric cleavage, suggesting that FGF signaling may stimulate dorsal midline development by inducing Zic2 expression. © 2007 Wiley Periodicals, Inc. Develop Neurobiol, 2008
Expression pattern of peptidylarginine deiminase in rat and human Schwann cells
Authors: Keilhoff Gerburg , Prell Tino , Langnaese Kristina , Mawrin Christian , Simon Michel , Fansa Hisham , Nicholas Anthony P.
Published: October 2007

The peptidylarginine deiminase (PAD) family of enzymes are responsible for conversion of protein‐bound arginine to citrulline in most tissues of the body and are garnering increased interest for their physiological and pathological roles. Although it has been shown that oligodendrocytes of the CNS express the PAD isoenzyme type 2, nothing is presently known about PAD expression in Schwann cells, the myelinating cells of the PNS. To evaluate PAD expression in the PNS, cultivated rat and human Schwann cells and slices of fetal, juvenile, and normal and regenerated adult sciatic nerves were examined with RT‐PCR, Western blot, and immunohistochemical analysis. Samples from cerebellar cultures and skin served as positive controls. One of the principle findings was that cultivated Schwann cells expressed significant levels of mRNA and protein for the PAD isoenzymes 2 and 3. PAD1 and PAD4, however, were not expressed in any types of Schwann cells. Using double immunofluorescence, the majority of PAD2 staining was localized in immature cell stages. Moreover, increased amounts of PAD2, PAD3, and peptidyl‐citrulline were also found in human fetal and rat juvenile and regenerated sciatic nerves as compared to similar normal adult specimens. Neuronal and inducible nitric oxide synthases, enzymes that convert free arginine to citrulline, were also expressed in Schwann cells; however, their massive induction by LPS/K+, was not reflected in an enhanced peptidyl‐citrulline immunosignal. These data suggest that, similar to the CNS, citrullination of proteins may also exert a specific role in thecourse of PNS development and repair. © 2007 Wiley Periodicals, Inc. Develop Neurobiol, 2008
Mas‐allatotropin in the developing antennal lobe of the sphinx moth Manduca sexta: Distribution, time course, developmental regulation, and colocalization with other neuropeptides
Authors: Utz Sandra , Huetteroth Wolf , Vömel Matthias , Schachtner Joachim
Published: October 2007

The paired antennal lobes (ALs) of the sphinx moth Manduca sexta serve as a well‐established model for studying development of the primary integration centers for odor information in the brain. To further reveal the role of neuropeptides during AL development, we have analyzed cellular distribution, developmental time course, and regulation of the neuropeptide M. sexta allatotropin (Mas‐AT). On the basis of morphology and appearance during AL formation, seven major types of Mas‐AT‐immunoreactive (ir) cells could be distinguished. Mas‐AT‐ir cells are identified as local, projection, and centrifugal neurons, which are either persisting larval or newly added adult‐specific neurons. Complementary immunostaining with antisera against two other neuropeptide families (A‐type allatostatins, RFamides) revealed colocalization within three of the Mas‐AT‐ir cell types. On the basis of this neurochemistry, the most prominent type of Mas‐AT‐ir neurons, the local AT neurons (LATn), could be divided in three subpopulations. The appearance of the Mas‐AT‐ir cell types occurring during metamorphosis parallels the rising titer of the developmental hormone 20‐hydroxyecdysone (20E). Artificially shifting the 20E titer to an earlier developmental time point resulted in the precocious occurrence of Mas‐AT immunostaining. This result supports the hypothesis that the pupal rise of 20E is causative for Mas‐AT expression during AL development. Comparing localization and developmental time course of Mas‐AT and other neuropeptides with the time course of AL formation suggests various functions for these neuropeptides during development, including an involvement in the formation of the olfactory glomeruli. © 2007 Wiley Periodicals, Inc. Develop Neurobiol, 2008
Gonadotropin‐releasing hormone‐1 (GnRH‐1) is involved in tooth maturation and biomineralization
Authors: Tiong Jean , Locastro Thomas , Wray Susan
Published: October 2007

Gonadotropin releasing‐hormone‐1 (GnRH‐1) is expressed in mouse incisors during development. In this report, we identify (1) cell type(s) that express GnRH‐1 throughout tooth development, (2) the GnRH‐1 receptor, and (3) the role of GnRH‐1/GnRH‐1 receptor signaling in tooth maturation. Results show that GnRH‐1‐positive cells in dental epithelium differentiate and populate multiple tooth structures including ameloblast and papillary layers that are involved in enamel formation and mineralization. The GnRH‐1 receptor was present, and in vitro a GnRH‐1 antagonist attenuated incisor GnRH‐1 cell expression. In vivo, in mice lacking GnRH‐1 (−/−), the incisors were discolored, longer, and more curved compared to wildtype. Elemental analysis of calcium, phosphorus, and iron revealed changes in −/− incisors consistent with GnRH‐1 affecting movement of minerals into the dental matrix. In sum, in tooth development a signal transduction pathway exists for GnRH‐1 via the GnRH‐1 receptor and disruption of such signaling affects incisor growth and biomineralization. Developmental Dynamics 236:2980–2992, 2007. Published 2007 Wiley‐Liss, Inc.
Transdifferentiation in developmental biology, disease, and in therapy
Authors: Thowfeequ Shifaan , Myatt Emily‐Jane , Tosh David
Published: October 2007

Transdifferentiation (or metaplasia) refers to the conversion of one cell type to another. Because transdifferentiation normally occurs between cells that arise from the same region of the embryo, understanding the molecular and cellular events in cell type transformations may help to explain the mechanisms underlying normal development. Here we review examples of transdifferentiation in nature focusing on the possible role of cell type switching in metamorphosis and regeneration. We also examine transdifferentiation in mammals in relation to disease and the use of transdifferentiated cells in cellular therapy. Developmental Dynamics 236:3208–3217, 2007. © 2007 Wiley‐Liss, Inc.
dTrf2 is required for transcriptional and developmental responses to ecdysone during Drosophila metamorphosis
Authors: Bashirullah Arash , Lam Geanette , Yin Viravuth P. , Thummel Carl S.
Published: October 2007

The TATA box‐binding protein (TBP) related factor 2 (TRF2) has been well characterized at a biochemical level and in cultured cells. Relatively little, however, is known about how TRF2 functions in specific biological pathways during development. Here, we show that Drosophila TRF2 (dTRF2) plays an essential role in responses to the steroid hormone ecdysone during the onset of metamorphosis. Hypomorphic dTrf2 mutations lead to developmental arrest during prepupal and early pupal stages with defects in major ecdysone‐triggered biological responses, including puparium formation, anterior spiracle eversion, gas bubble translocation, adult head eversion, and larval salivary gland cell death. The transcription of key ecdysone‐regulated target genes is delayed and reduced in dTrf2 mutants. dTrf2 appears to be required for the proper timing and levels of ecdysone‐regulated gene expression required for entry into metamorphosis. Developmental Dynamics 236:3173–3179, 2007. © 2007 Wiley‐Liss, Inc.
Gene expression patterns underlying proximal–distal skeletal segmentation in late‐stage zebrafish,Danio rerio
Authors: Crotwell Patricia L. , Mabee Paula M.
Published: October 2007

Timing and pattern of expression of ten candidate segmentation genes or gene pairs were reviewed or examined in developing median fins of late‐stage zebrafish,Danio rerio. We found a general correspondence in timing and pattern of expression between zebrafish fin radial segmentation and tetrapod joint development, suggesting that molecular mechanisms underlying radial segmentation have been conserved over 400 million years of evolution. Gene co‐expression during segmentation (5.5–6.5 mm SL) is similar between tetrapods and zebrafish:bmp2b,bmp4,chordin, andgdf5in interradial mesenchyme and ZS;bapx1,col2a1,noggin3, andsox9ain chondrocytes. Surprisingly,wnt9ais not expressed in the developing median fins, thoughwnt9bis detected. In contrast to all other candidate segmentation genes we examined,bapx1is not expressed in the caudal fin, which does not segment. Together, these data suggest a scenario of gene interactions underlying radial segmentation based on the patterns and timing of candidate gene expression. Developmental Dynamics 236:3111–3128, 2007 © 2007 Wiley‐Liss, Inc.
Gateway compatible vectors for analysis of gene function in the zebrafish
Authors: Villefranc Jacques A. , Amigo Julio , Lawson Nathan D.
Published: October 2007

The recent establishment of recombination‐based cloning systems has greatly facilitated the analysis of gene function by allowing rapid and high‐efficiency generation of plasmid constructs. However, the use of such an approach in zebrafish requires the availability of recombination‐compatible plasmids that are appropriate for functional studies in zebrafish embryos. In this work, we describe the construction and validation of Gateway compatible vectors based on commonly used zebrafish plasmids. We have generated pCS‐based plasmids that allow rapid generation of both N‐terminal and C‐terminal fusion proteins, and we demonstrate that mRNA synthesized from these plasmids encodes functional native or fusion proteins in injected zebrafish embryos. In parallel, we have established similar Gateway plasmids containing Tol2 cis elements that promote efficient integration into the zebrafish genome and allow expression of native or fusion proteins in a tissue‐specific manner in the zebrafish embryo. Finally, we demonstrate the use of this system to rapidly identify tissue‐specific cis elements to aid the establishment of blood vessel‐specific transgenic constructs. Taken together, this work provides an important platform for the rapid functional analyses of open reading frames in zebrafish embryos. Developmental Dynamics 236:3077–3087, 2007. © 2007 Wiley‐Liss, Inc.
Abnormal venous and arterial patterning in chordin mutants
Authors: Délot Emmanuele , Shneyder Natalya , Zhang Hanwei , Bachiller Daniel
Published: October 2007

Injection of colored methyl salicilate into the atria of fixed mouse embryos reveal the pattern of developing veins. See Délot et al., Developmental Dynamics 236:2586–2593. © 2007 Wiley‐Liss, Inc.
Improvement of microwave power amplifier intermodulation distortion by a novel second‐harmonic short‐circuit termination
Authors: Takayama Yoichiro , Watanabe Kazushi , Yamaguchi Kazuyuki , Fujita Takayuki , Maenaka Kazusuke
Published: October 2007

The intermodulation distortion characteristics of a microwave Si MOSFET power amplifier are improved by realization of a true second harmonic short‐circuit termination of the drain. By the use of a circuit configuration taking account of the parasitic inductance of the FET drain, second harmonic short‐circuiting of the drain is realized. First, a two‐variable Taylor series expansion model of the drain current with respect to the gate voltage and the drain voltage is used and an approximate analysis by the perturbation method, including the low frequency (signal difference frequency) and second harmonic load dependence of the third‐order intermodulation distortion, is used for an analysis of the intermodulation distortion and its asymmetry. Next, a 1‐GHz Si MOSFET power amplifier is fabricated. Reduction of the intermodulation distortion and its asymmetry is realized by introducing a true second harmonic short circuit for the drain. © 2007 Wiley Periodicals, Inc. Electron Comm Jpn Pt 2, 90(11): 9–16, 2007; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ecjb.20344
Measurement of temperature‐dependent complex permittivity for materials using cylindrical resonator under microwave irradiation
Authors: Guan Yong , Nikawa Yoshio
Published: October 2007

A cylindrical resonator operating in TM010 mode at a frequency of 2.45 GHz is used. A sample placed in the resonator is dielectrically heated, amplifying the output of the vector network analyzer by a Radio Frequency (RF) power amplifier. The transmission coefficient of the resonator is measured while heating, and the temperature dependence of the complex permittivity of the material is determined. The results are discussed. By calculating the rigorous analysis for the electromagnetic field distribution, the error of measurement by perturbation is evaluated, and it is verified that the measurement error for the relative dielectric constant does not exceed 3.5%. © 2007 Wiley Periodicals, Inc. Electron Comm Jpn Pt 2, 90(11): 1–8, 2007; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ecjb.20346
Digital terrestrial television transmission over OFDM/FM using satellite communications system
Authors: Anwar Khoirul , Hara Takao , Okada Minoru , Yamamoto Heiichi
Published: October 2007

The new digital terrestrial television transmission signals use the OFDM system. This system has the fundamental problem that the peak power to average power ratio (PAPR) of the signal is significant. In this paper, a satellite communication system is proposed as a supplemental network for digital terrestrial broadcasting. It is shown that effective use of the satellite power becomes possible at a large PAPR by using the FM system with a constant signal envelope as the secondary modulation, so that the problem can be resolved. It is shown analytically that a larger FM gain can be obtained by limiting the peak voltage of the OFDM signal by clipping. The degradation of the BER caused by clipping is derived by simulation and the system is optimized with regard to the degree of clipping. Taking the size and operational cost of the receiving station into account, channel design is performed assuming a real satellite channel. The overall transmission characteristics such as the transmission capacity of the satellite repeater and the channel quality are discussed. © 2007 Wiley Periodicals, Inc. Electron Comm Jpn Pt 2, 90(11): 74–84, 2007; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ecjb.20385
Distortion‐free fusion of multiple video camera images using EPI analysis
Authors: Mikami Takeshi , Oo Thanda , Ono Shintaro , Kawasaki Hiroshi , Ohsawa Yutaka , Ikeuchi Katsushi
Published: October 2007

This paper presents a method that uses an Epipolar Plane Image (EPI) to calibrate multiple video cameras and obtain distortion‐free fusion of these images. Generally speaking, the optical center of a camera exists inside its body making it physically difficult to focus these images at one point in multiple cameras. When fusing these types of camera images, distortion will occur unless three‐dimensional shape information is used. In this paper we perform distortion‐free image fusion by bringing these optical centers into agreement in a spatiotemporal field based on conditions in which multiple video cameras are installed on a movable object. The agreement points of the optical centers are automatically calculated by means of EPI matching. Because this process utilizes time‐variant redundancy of each camera image, a stable corresponding relationship is obtained even when there is no spatial overlap of the photographic range making it possible to install cameras with comparative freedom. In addition, because it is possible to ensure sufficient quality without using special external synchronization devices or position measurement devices, this method is also suitable for acquiring textures of large‐scale real scenes, such as urban spaces. © 2007 Wiley Periodicals, Inc. Electron Comm Jpn Pt 2, 90(11): 85–98, 2007; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ecjb.20396
The parameter dependence of the inverse function delayed model on the success rate of combinatorial optimization problems
Authors: Sato Akari , Hayakawa Yoshihiro , Nakajima Koji
Published: October 2007

Much research has been performed regarding attempts to solve NP hard or NP complete problems using neural networks, because high‐speed solutions then become possible through parallel processing. However, there is still the local minima problem. The Inverse Function Delayed (ID) model used in this paper is shown to be a powerful avoidance algorithm for the local minima problem, because the dynamics of the model can cause negative resistance and the local minima can be destabilized by this negative resistance. In this paper, the differences with the conventional Hopfield model and the hysteresis neuron model, due to the parameters of the ID model, are discussed successively. Moreover, from a general energy function E of the optimization problem, when a static output state is the solution representation, it is shown that the global minima and the local minima can be separated using the ID model in a problem where E=0 in the global minimum state. Afterwards, the parameter dependence of the success rate is discussed. As a result, a numerical experiment confirmed that a wide optimal parameter range showing a 100% success rate is obtained, though there is a slight special oscillating state (limit cycle). © 2007 Wiley Periodicals, Inc. Electron Comm Jpn Pt 2, 90(11): 41–54, 2007; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ecjb.20402
Appearance reproduction of high‐dynamic‐range video based on human visual models
Authors: Hirai Keita , Nakaguchi Toshiya , Tsumura Norimichi , Miyake Yoichi
Published: October 2007

In this paper, we propose a method for improving image quality in order to match precisely the appearances of recorded video sequences with those of real scenes. Captured video and still images by cameras often have saturated and underexposed areas due to their limited dynamic range. Therefore, it is required to acquire images with a wide dynamic range and much tone data for the accurate reproduction of appearances. In addition, it is important to apply color reproduction processing based on human visual models to recorded videos because the appearances between the videos and real scenes differ due to the characteristics of human vision. In our method, a photometric high‐dynamic‐range (PHDR) video is generated by using a recorded video sequence and metadata of a camera such as the sensitivity (speed), aperture, and shutter speed. The PHDR video consists of the values of high‐dynamic‐range tone and absolute luminance. After the generation of a PHDR video, the video is processed by using color reproduction techniques based on spatiotemporal visual adaptation models for the accurate reproduction of appearances. Our results show that the proposed method reproduces fine appearance of videos which is the close appearance of real scenes. © 2007 Wiley Periodicals, Inc. Electron Comm Jpn Pt 2, 90(11): 55–64, 2007; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ecjb.20403
A method to generate formulas for temporal logic satisfiability checkers
Authors: Sekizawa Toshifusa , Takai Toshinori , Tanabe Yoshinori , Takahashi Koichi
Published: October 2007

In order to evaluate the performance of temporal logic satisfiability checkers, a benchmark with test formulas is required, as well as analysis of the complexity of algorithms. However, there seem to be no clear criteria of the formulas for benchmarks. Thus, to evaluate the performance of satisfiability checkers for new logics, we must prepare test formulas for the logic. In this paper, we propose a systematic method to generate formulas of two‐way CTL, which are intended to be benchmark formulas for satisfiability checkers. We also discuss the criteria of test formulas. Finally, we present formulas obtained by our method and describe the results of experiments with our two‐way CTL satisfiability checker. © 2007 Wiley Periodicals, Inc. Electron Comm Jpn Pt 2, 90(11): 99– 108, 2007; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ecjb.20410
Statistical PET image reconstruction using duality of nonlinear programming
Authors: Li Meihua , Kudo Hiroyuki
Published: October 2007

In recent years technology has been in practical use which performs PET image reconstruction using a Maximum Likelihood (ML) estimation or a Maximum A Posteriori (MAP) estimation to improve the quality of the reconstructed images. Generally speaking, these methods require minimization of a convex cost function based on an iterative method and are accompanied by many problems related to the computational complexity. In this paper we propose a new Row‐Action type image reconstruction method that uses duality of nonlinear programming to rapidly converge with a small computational complexity per iteration. The proposed method has various advantages compared to the conventional methods. Examples of the advantages include: (1) avoids limit cycles and rapidly converges to true solutions, (2) can easily handle nonnegative constraint, (3) sufficient reconstructed images are obtained in one iteration, (4) easy to implement with a small number of empirically set parameters. The effectiveness of the proposed method is presented through simulated experiments and results of applications to clinical PET data are also presented. © 2007 Wiley Periodicals, Inc. Electron Comm Jpn Pt 2, 90(11): 122–131, 2007; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ecjb.20412
Error estimation of load switching signal from contactless IC card and proposal of approximation method for discrete Fourier transform
Authors: Nakano Sadahiko , Ohtani Yoshimitsu
Published: October 2007

ISO drafts for identification cards, namely, contactless integrated circuit cards, provide detailed methods for measuring load‐switching (LS) signals that transmit data from a card to a reader‐writer, to assure the interchangeability of cards and/or reader‐writers. They recommend a discrete Fourier transform (DFT) program for the LS‐signal spectrum and provide the maximum permissible measurement error. However, the influences of inherent error in DFT and also of the inaccuracy of measuring instruments have not been clarified. Therefore, under the present circumstances, correct LS‐signal spectra are not obtained. Furthermore, the measurement error cannot be accurately estimated. This paper, first, derives an equation for estimating the error caused by measuring instruments. Second, it proposes a DFT approximation method, called the DFT averaging method, which compensates for the natural defect that prevents DFT from getting correct spectra because the ratio of the DFT window period to the LS‐signal cycle is not a round integer. Experimental verification with quasi LS‐signals generated by circuits showed that the theoretical and experimental values of LS‐signal spectral error were very similar. The DFT averaging method applied to real LS‐signals from contactless IC cards usefully decreased the spectral error from 19% to 1%. © 2007 Wiley Periodicals, Inc. Electron Comm Jpn Pt 2, 90(11): 26–40, 2007; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ecjb.20419
Optically differential reconfigurable gate array
Authors: Miyano Mototsugu , Watanabe Minoru , Kobayashi Fuminori
Published: October 2007

Recent years have seen the development of optically reconfigurable gate arrays, which can be reconfigured using light at high speeds that cannot be implemented with electrical wiring. However, optically reconfigurable gate arrays have reconfiguration speeds of 16 to 20 µs, which is fast compared to FPGAs (Field Programmable Gate Arrays), but high‐speed reconfiguration, approaching the operating clock of a mounted circuit, has not been implemented. Also, partial reconfiguration, which is indispensable for frequent dynamic reconfiguration, has not been considered. The authors propose an Optically Differential Reconfigurable Gate Array (ODRGA), which can be reconfigured at high speeds close to the operating clock of a mounted circuit and which allows partial reconfiguration of any zone in bit units. This paper includes an overview of ODRGA and introduces the optically differential reconfigurable architecture, with which arbitrary, partial reconfiguration is possible, as well as the optically reconfigurable architecture enabling high‐speed optical reconfiguration. Then, it is demonstrated that high‐speed optical reconfiguration at 200 ns, the world's fastest system‐level optical reconfiguration, is possible with an optical system using a pulse laser diode wherein nanosecond optical reconfiguration is possible with a prototype stand‐alone VLSI chip. Finally, it is made clear that, in the future, improvement to the optical components will make possible nanosecond high‐speed optical reconfiguration at the system level as well. © 2007 Wiley Periodicals, Inc. Electron Comm Jpn Pt 2, 90(11): 132–139, 2007; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ecjb.20420
IDO expands human CD4+CD25high regulatory T cells by promoting maturation of LPS‐treated dendritic cells
Authors: Hill Marcelo , Tanguy‐Royer Séverine , Royer Pierre , Chauveau Christine , Asghar Kashif , Tesson Laurent , Lavainne Frédéric , Rémy Séverine , Brion Régis , Hubert François‐Xavier , Heslan Michèle , Rimbert Marie , Berthelot Laureline , Moffett John R. , Josien Régis , Grégoire Marc , Anegon Ignacio
Published: October 2007

We have previously shown that human monocyte‐derived dendritic cells (DC) express indoleamine 2,3‐dioxygenase (IDO), as well as several other enzymes of the kynurenine pathway at the mRNA level upon maturation. The tolerogenic mechanisms of this pathway remain unclear. Here we show that LPS‐treated DC metabolize tryptophan as far as quinolinate. We found that IDO contributes to LPS and TNF‐α + poly(I:C)‐induced DC maturation since IDO inhibition using two different inhibitors impairs DC maturation. IDO knock‐down using short‐hairpin RNA also led to diminished LPS‐induced maturation. In line with these results, the tryptophan‐derived catabolites 3‐hydroxyanthranilic acid and 3‐hydroxykynurenine increased maturation of LPS‐treated DC. Concerning the molecular mechanisms of this effect, IDO acts as an intermediate pathway in LPS‐induced production of reactive oxygen species and NF‐κB activation, two processes that lead to DC maturation. Finally, we show that mature DC expand CD4+CD25high regulatory T cells in an IDO‐dependent manner. In conclusion, we show that IDO constitutes an intermediate pathway in DC maturation leading to expansion of CD4+CD25high regulatory T cells.
Cloning of B cell‐specific membrane tetraspanning molecule BTS possessing B cell proliferation‐inhibitory function
Authors: Suenaga Tadahiro , Arase Hisashi , Yamasaki Sho , Kohno Masayuki , Yokosuka Tadashi , Takeuchi Arata , Hattori Takamichi , Saito Takashi
Published: October 2007

Lymphocyte proliferation is regulated by signals through antigen receptors, co‐stimulatory receptors, and other positive and negative modulators. Several membrane tetraspanning molecules are also involved in the regulation of lymphocyte growth and death. We cloned a new B cell‐specific tetraspanning (BTS) membrane molecule, which is similar to CD20 in terms of expression, structure and function. BTS is specifically expressed in the B cell line and its expression is increased after the pre‐B cell stage. BTS is expressed in intracellular granules and on the cell surface. Overexpression of BTS in immature B cell lines induces growth retardation through inhibition of cell cycle progression and cell size increase without inducing apoptosis. This inhibitory function is mediated predominantly by the N terminus of BTS. The development of mature B cells is inhibited in transgenic mice expressing BTS, suggesting that BTS is involved in the in vivo regulation of B cells. These results indicate that BTS plays a role in the regulation of cell division and B cell growth.