bluuebunny/crossref_metadata_2025 huggingface dataset:
Diminished transforming growth factor β2 production leads to increased expression of a profibrotic procollagen α2 type I messenger RNA variant in embryonic fibroblasts of UCD‐200 chickens, a model for systemic sclerosis
Authors: Prelog Martina , Scheidegger Paul , Peter Silvia , Gershwin M. Eric , Wick Georg , Sgonc Roswitha
Published: June 2005

Objective

A procollagen α2(I) messenger RNA (mRNA) variant, with a 115‐bp band and an expected band of 180 bp, was found to be increased during early, acute scleroderma‐like disease in UCD‐200 chickens. The present study investigated the influence of cytokines on the expression of these 2 proα2(I) mRNA variants.

Methods

Embryonic fibroblasts of UCD‐200 chickens (UCD‐200‐CEF) and normal white leghorns (NWL‐CEF) were grown in 3‐dimensional collagen gels. Procollagen mRNA expression was analyzed by RNase protection assay, and proliferation was determined by 3H‐thymidine incorporation. Transforming growth factor β1 (TGFβ1) and TGFβ2 were measured in culture supernatants by enzyme‐linked immunosorbent assay.

Results

Compared with NWL‐CEF, UCD‐200‐CEF expressed 7.2 times more of the smaller profibrotic proα2(I) mRNA variant. TGFβ1 stimulated the proliferation of UCD‐200‐CEF, but not NWL‐CEF. The 115 bp:180 bp ratio was increased by TGFβ1 in both NWL‐CEF and UCD‐CEF. TGFβ2 and TGFβ3 reduced the expression of the profibrotic proα2(I) mRNA in UCD‐200‐CEF to the same levels observed in healthy control NWL‐CEF. In culture supernatants, NWL‐CEF produced 4.1 times more TGFβ2 than that produced by UCD‐CEF. Inhibition of endogenous TGFβ2 in NWL‐CEF resulted in the same 115 bp:180 bp ratio as seen in untreated UCD‐CEF.

Conclusion

TGFβ2 reduces the expression of a profibrotic proα2(I) mRNA variant in UCD‐200‐CEF. The constitutive overproduction of this proα2(I) mRNA variant and the diminished synthesis of TGFβ2 in untreated UCD‐200‐CEF suggest that TGFβ2 can act as an antifibrotic cytokine and might be a key player during fibrosis onset. These results shed light on the contradictory observations regarding the role of TGFβ2 in human systemic sclerosis.
Tumor necrosis factor inhibits conversion of dehydroepiandrosterone sulfate (DHEAS) to DHEA in rheumatoid arthritis synovial cells: A prerequisite for local androgen deficiency
Authors: Weidler Claudia , Struharova Sona , Schmidt Martin , Ugele Bernhard , Schölmerich Jürgen , Straub Rainer H.
Published: June 2005

Objective

Use of anti–tumor necrosis factor (anti‐TNF) antibody therapy in rheumatoid arthritis (RA) has expanded our understanding of possible mechanisms by which this treatment reduces inflammation. Beyond its effects on local immune responses, anti‐TNF treatment may also modulate the local hormone supply. Because androgens are thought to inhibit immune responses, their presence in inflamed tissue is an additional important antiinflammatory factor.

Methods

We investigated conversion of the ubiquitous dehydroepiandrosterone sulfate (DHEAS), the biologically inactive precursor of DHEA, to the androgen DHEA in mixed synovial cells from patients with RA and patients with osteoarthritis (OA), making use of thin‐layer chromatography and phosphorimaging. Using immunohistochemical analysis, we detected the key enzyme, steroid sulfatase.

Results

DHEAS‐to‐DHEA conversion in synovial cells from patients with RA was significantly lower than that in synovial cells from patients with OA (mean ± SEM 3.3 ± 0.5% versus 6.0 ± 0.9% of applied 3H‐DHEAS per 106 synovial cells; P = 0.042). In RA, but not in OA, the level of converted 3H‐DHEA was inversely correlated with the density of synovial macrophages (for RA, Rrank = −0.725, P = 0.005; for OA, Rrank = 0.069, P not significant [NS]) and T cells (for RA, Rrank = −0.621, P = 0.024; for OA, Rrank = 0.247, P NS). Double immunohistochemistry analysis revealed that steroid sulfatase was located mainly in synovial macrophages but was also observed in fibroblasts. Neutralization of TNF largely up‐regulated the conversion of DHEAS to DHEA in RA, but not in OA. A similar neutralizing effect was observed with polyclonal human immunoglobulins; this effect is most probably mediated via TNF neutralization at low TNF concentrations.

Conclusion

These data indicate that TNF inhibits the conversion of DHEAS to DHEA in RA synovial cells. Because androgens are antiinflammatory mediators, TNF‐induced inhibition of the local androgen supply is a supplementary proinflammatory factor. Consequently, anti‐TNF strategies may also exert their positive effects by increasing tissue androgens.
Empirical and theoretical dosimetry in support of whole body radio frequency (RF) exposure in seated human volunteers at 220 MHz
Authors: Allen Stewart J. , Adair Eleanor R. , Mylacraine Kevin S. , Hurt William , Ziriax John
Published: June 2005

This study reports the dosimetry performed to support an experiment that measured physiological responses of seated volunteer human subjects exposed to 220 MHz fields. Exposures were performed in an anechoic chamber which was designed to provide uniform fields for frequencies of 100 MHz or greater. A vertical half‐wave dipole with a 90° reflector was used to optimize the field at the subject's location. The vertically polarized E field was incident on the dorsal side of the phantoms and human volunteers. The dosimetry plan required measurement of stationary probe drift, field strengths as a function of distance, electric and magnetic field maps at 200, 225, and 250 cm from the dipole antenna, and specific absorption rate (SAR) measurements using a human phantom, as well as theoretical predictions of SAR with the finite difference time domain (FDTD) method. A NBS (National Bureau of Standards, now NIST, National Institute of Standards and Technology, Boulder, CO) 10 cm loop antenna was positioned 150 cm to the right, 100 cm above and 60 cm behind the subject (toward the transmitting antenna) and was read prior to each subject's exposure and at 5 min intervals during all RF exposures. Transmitter stability was determined by measuring plate voltage, plate current, screen voltage and grid voltage for the driver and final amplifiers before and at 5 min intervals throughout the RF exposures. These dosimetry measurements assured accurate and consistent exposures. FDTD calculations were used to determine SAR distribution in a seated human subject. This study reports the necessary dosimetry to precisely control exposure levels for studies of the physiological consequences of human volunteer exposures to 220 MHz. Bioelectromagnetics 26:440–447, 2005. Published 2005 Wiley‐Liss, Inc.
Bemessung von Dübeln am Bauteilrand unter Querlast: Ingenieurmäßiger Ansatz zur Berücksichtigung der Lastrichtung
Authors: Mallée Rainer , Pusill‐Wachtsmuth Peter
Published: May 2005

Es wird ein allgemeingültiger Bemessungsansatz für Dübel unter Querlast am Bauteilrand bei der Versagensart Betonkantenbruch abgeleitet. Die Richtung der Querlast wird bei der Lastverteilung auf die einzelnen Dübel einer Gruppe berücksichtigt. Damit kann das Modell für Anwendungen ohne und mit Lochspiel sowie für Querlasten und für Torsionsmomente angewendet werden.
Anspruchsvolles Sichtbetonbauwerk: Neubau der Universität Brixen
Authors: Taferner Josef , Sodeikat Christian , Eltze Rainer
Published: May 2005

Wegen der vorhandenen Komplexität sind bei der Planung und Herstellung von Sichtbeton erfahrene Sonderfachleute gefragt, die den dazugehörigen Willen und das erforderliche Engagement zur Vorbereitung, Koordination und baubegleitenden Kontrolle und Steuerung bei der Herstellung besitzen. Sehenswerte Ergebnisse lassen sich nur dann erreichen, wenn Wissensvermittlung, Informationsfluß, Fachkenntnisse, Erfahrungen und Engagement aller Beteiligten zusammenwirken und wenn der Bauherr bereit ist, diese planerischen und ausführungstechnischen Leistungen entsprechend zu vergüten. Am Beispiel des Baues der Universität Brixen soll gezeigt werden, wie trotz hoher architektonischer Anforderungen an das Tragwerk mit filigranen Bauteilen und bauphysikalischen Randbedingungen ein alle Seiten zufriedenstellendes Sichtbetonergebnis erzielt werden kann. Dabei waren besondere Überlegungen in statisch‐konstruktiver, betontechnologischer und ausführungstechnischer Hinsicht erforderlich.
Applications of Binary Segmentation to the Estimation of Quantal Response Curves and Spatial Intensity
Authors: Yang Tae Y. , Swartz Tim B.
Published: June 2005

This paper explores the use of binary segmentation procedures in two applications. The first application is concerned with the estimation of nonparametric quantal response curves. With Bernoulli data and an assumed monotone increasing curve, this gives rise a change‐point model where the change points are determined using a sequence of nested hypothesis tests of whether a change point exists. The second application concerns cluster identification and inference for spatial data where the shape of the clusters and the number of clusters is unknown. The procedure involves a sequence of nested hypothesis tests of a single cluster versus a pair of distinct clusters. Examples of both applications are provided. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Combination of Dsb coexpression and an addition of sorbitol markedly enhanced soluble expression of single‐chain Fv in Escherichia coli
Authors: Sandee Duanpen , Tungpradabkul Sumalee , Kurokawa Yoichi , Fukui Kiichi , Takagi Masahiro
Published: June 2005

Many eukaryotic proteins have been produced successfully in Escherichia coli. However, not every gene can be expressed efficiently in this organism. Most proteins, especially those with multiple disulfide bonds, have been shown to form insoluble protein or inclusion body in E. coli. An inactive form of protein would require an in vitro refolding step to regain biological functions. In this study, we described the system for soluble expression of a single‐chain variable fragment (scFv) against hepatocellular carcinoma (Hep27scFv) by coexpressing Dsb protein and enhancing with medium additives. The results revealed that overexpression of DsbABCD protein showed marked effect on the soluble production of Hep27scFv, presumably facilitating correct folding. The optimal condition for soluble scFv expression could be obtained by adding 0.5M sorbitol to the culture medium. The competitive enzyme‐linked immunosorbent assay (ELISA) indicated that soluble scFv expressed by our method retains binding activity toward the same epitope on a hepatocellular carcinoma cell line (HCC‐S102) recognized by intact antibody (Ab) (Hep27 Mab). Here, we report an effective method for soluble expression of scFv in E. coli by the Dsb coexpression system with the addition of sorbitol medium additive. This method might be applicable for high‐yield soluble expression of proteins with multiple disulfide bonds. © 2005 Wiley Periodicals, Inc.
Monitoring complex media fermentations with near‐infrared spectroscopy: Comparison of different variable selection methods
Authors: Ferreira Ana P. , Alves Teresa P. , Menezes José C.
Published: June 2005

Near‐infrared spectroscopy (NIRS) is known to be a suitable technique for rapid fermentation monitoring. Industrial fermentation media are complex, both chemically (ill‐defined composition) and physically (multiphase sample matrix), which poses an additional challenge to the development of robust NIRS calibration models. We investigated the use of NIRS for at‐line monitoring of the concentration of clavulanic acid during an industrial fermentation. An industrial strain of Streptomyces clavuligerus was cultivated at 200‐L scale for the production of clavulanic acid. Partial least squares (PLS) regression was used to develop calibration models between spectral and analytical data. In this work, two different variable selection methods, genetic algorithms (GA) and PLS‐bootstrap, were studied and compared with models built using all the spectral variables. Calibration models for clavulanic acid concentration performed well both on internal and external validation. The two variable selection methods improved the predictive ability of the models up to 20%, relative to the calibration model built using the whole spectra. © 2005 Wiley Periodicals, Inc.
Raman optical activity of simple alanyl peptides: Backscattering in‐phase dual circular polarization measurements in aqueous solution
Authors: Yu Gu‐sheng , Che Diping , Freedman Teresa B. , Nafie Laurence A.
Published: May 2005

We report the measurement of backscattering in‐phase dual circular polarization (DCPI) Raman optical activity (ROA) for the simple alanyl peptides L‐alanyl‐L‐alanine ([L‐Ala]2), L‐alanylglycine (L‐Ala‐Gly), glycyl‐L‐alanine (Gly‐L‐Ala), and L‐alanyl‐L‐alanyl‐L‐alanine ([L‐Ala]3) in aqueous solutions. Empirical correlations between ROA features and the amino acid composition of the peptides are described. It is shown that the sum of the DCPIROA spectra for L‐Ala‐Gly and Gly‐L‐Ala is nearly the same as the corresponding ROA spectrum for (L‐Ala)2. Additionally, the DCPIROA spectrum for (L‐Ala)2 is very close to that of (L‐Ala)3, as has been observed previously using backscattering unpolarized incident circular polarization (ICPu) ROA. The ROA contributions of the different L‐Ala groups, which occur separately in the two glycyl peptides of alanine and jointly in (L‐Ala)2, are described in terms of the extent of vibrational coupling between peptide subunits. From these results, it appears that ROA has a more local sensitivity to vibrational coupling than is found in VCD or electronic circular dichroism. © 1995 John Wiley & Sons, Inc.
Fluorescence spectroscopy of 13′‐cis‐spheroidene at 170 K: A reason for the natural selection of the all‐trans configuration for the light‐harvesting function
Authors: Koyama Yasushi , Jiang Yue‐shun , Watanabe Yasutaka
Published: May 2005

As a follow‐up to fluorescence and fluorescence‐excitation spectroscopy at 170 K of all‐trans‐spheroidene free in solutions

Y. Watanabe, T. Kameyama, Y. Miki, M. Kuki, and Y. Koyama, “The 2′Ag− state and two additional low‐lying electronic states of spheroidene newly identified by fluorescence and fluorescence‐excitation spectroscopy at 170K,” Chem. Phys. Lett. 206, 62–68 (1993).

and bound to the light‐harvesting complex of Rhodobacter sphaeroides 2.4.1,

Y. Koyama, Y. Miki, T. Kameyama, R. J. Cogdell, and Y. Watanabe, “Low‐lying electronic levels of spheroidene bound to the light‐harvesting (LH2) complex of Rhodobacter sphaeroides 2.4.1. as determined by fluorescence and fluorescence‐excitation spectroscopy at 170K,” Chem. Phys. Lett. 208, 479–485 (1993).

13′‐cis‐spheroidene in n‐hexane solution has been examined for comparison. All‐trans‐spheroidene exhibits efficient internal conversion from the 3A to the 2A state and fluorescence from both the 2A and B states, while 13‐‐cis‐spheroidene exhibits internal conversion from the “3Ag‐” state to the “B” state and fluorescence only from the “B” state. Thus, all‐trans‐spheroidene can provide two channels of carotenoid‐to‐bacteriochlorophyll singlet‐energy transfer, while 13′‐cis‐spheroidene can provide only one. This must be a reason for the natural selection of the all‐trans configuration for the light‐harvesting function. © 1995 John Wiley & Sons, Inc.
Engineering Substrate Specificity of O6‐Alkylguanine‐DNA Alkyltransferase for Specific Protein Labeling in Living Cells
Authors: Juillerat Alexandre , Heinis Christian , Sielaff India , Barnikow Jan , Jaccard Hugues , Kunz Beatrice , Terskikh Alexey , Johnsson Kai
Published: June 2005

Fusion proteins of human O6‐alkylguanine‐DNA alkyltransferase (AGT) can be specifically labeled with a wide variety of synthetic probes in mammalian cells; this makes them an attractive tool for studying protein function. However, to avoid undesired labeling of endogenous wild‐type AGT (wtAGT), the specific labeling of AGT fusion proteins has been restricted to AGT‐deficient mammalian cell lines. We present here the synthesis of an inhibitor of wtAGT and the generation of AGT mutants that are resistant to this inhibitor. This enabled the inactivation of wtAGT and specific labeling of fusion proteins of the AGT mutant in vitro and in living cells. The ability to specifically label AGT fusion proteins in the presence of endogenous AGT, after brief incubation of the cells with a small‐molecule inhibitor, should significantly broaden the scope of application of AGT fusion proteins for studying protein function in living cells.
An Effective Use of Benzoic Anhydride and Its Derivatives for the Synthesis of Carboxylic Esters and Lactones — Poweful and Convenient Mixed Anhydride Methods Promoted by Lewis Acids or Basic Catalysts
Authors: Shiina Isamu
Published: May 2005

For Abstract see ChemInform Abstract in Full Text.
Einflüsse der Säulenkonstruktion auf den HPLC‐Prozess
Authors: Boysen H. , Wozny G. , Guiochon G.
Published: June 2005

No abstracts.
Anwendung der Euler‐Euler‐Methode zur Simulation der Flüssigkeit/Feststoff‐Strömung im Strahlschlaufenapparat
Authors: Mier P. , Angst R. , Kraume M.
Published: June 2005

No abstracts.
Varianten‐Konzept für Pumpen in der chemischen Verfahrenstechnik
Authors: Schmitz R.
Published: June 2005

No abstracts.
Topographische Charakterisierung von Oberflächen im steriltechnischen Anlagenbau
Authors: Schmidt R. , Beck U. , Weigl B. , Gamer N. , Reiners G. , Sommer K.
Published: June 2005

No abstracts.
Modularer Aufbau von Biochips durch mikrostrukturierte Abscheidung von funktionellen Nanopartikeln
Authors: Weber A. , Knecht S. , Brunner H. , Tovar G.E.M.
Published: June 2005

No abstracts.
Reinigung jodhaltiger Spülwasser aus der Röntgenkontrastmittelproduktion mittels Nanofiltration: Prozessgestaltung und Modellierung
Authors: Drews A. , Klahm T. , Renk B. , Saygili M. , Baumgarten G. , Kraume M.
Published: June 2005

No abstracts.
Fed‐Batch‐Kultivierung tierischer Zellen – Eine Herausforderung zur adaptiven, modellbasierten Steuerung
Authors: Frahm B. , Hass V.C. , Lane P. , Munack A. , Märkl H. , Pörtner R.
Published: June 2005

No abstracts.
The melanoma antigen gene as a surveillance marker for the detection of circulating tumor cells in patients with breast carcinoma
Authors: Kwon Soim , Kang Seok Hyung , Ro Jungsil , Jeon Chang‐Ho , Park Jong‐Wook , Lee Eun Sook
Published: June 2005

BACKGROUND

Circulating occult tumors cells could be used for the surveillance of metastases after primary breast carcinoma therapy, but their detection is limited by the lack of specific molecular markers. Melanoma antigen genes (MAGEs), which are expressed in malignant tissues but not in normal tissues (except for placenta and testis), might provide such a marker. To date, however, the use of MAGEs in the detection of occult tumor cells using reverse transcription‐polymerase chain reaction (RT‐PCR) has been limited because of the heterogeneity and low expression of individual MAGEs in tumor tissues.

METHODS

We developed multiple MAGE‐recognizing primers (MMRPs) that were capable of binding to the cyclic DNA of 6 MAGE‐A gene subtypes (MAGE‐A1–MAGE‐A6). We assessed the ability of the MMRPs to detect the expression of MAGE‐A gene subtypes in peripheral blood obtained from patients with benign or malignant breast disease.

RESULTS

MAGE‐A gene expression was not detected in 32 patients with benign disease but was detected in 1 of 31 patients (3%) patients with negative lymph node breast carcinoma, in 10 of 52 patients (19%) with 1–3 positive lymph nodes, in 11 of 53 patients (21%) with ≥ 4 positive lymph nodes, and in 20 of 52 patients (39%) with metastatic disease. The results were statistically significant (P < 0.0001; chi‐square test for linear‐by‐linear association). The results also showed that the detection of MAGE‐A gene expression in the blood predicted tumor progression or recurrence.

CONCLUSIONS

The results suggested that MAGE‐A gene expression may be used for the surveillance of circulating breast carcinoma cells after primary therapy by RT‐nested PCR using MMRPs. Cancer 2005. © 2005 American Cancer Society.
The use of inflammation by tumor cells
Authors: Arias Jose‐Ignacio , Aller María‐Angeles , Arias Jaime
Published: June 2005

The authors proposed that the progression of benign tumors is based especially on the host reaction or desmoplasia., whereas malignant tumor cells can adopt an inflammatory phenotype that would evolve in three hypothetical functional phases with trophic meaning.
Malignant insulinoma
Authors: Hirshberg Boaz , Cochran Craig , Skarulis Monica C. , Libutti Steven K. , Alexander H. Richard , Wood Bradford J. , Chang Richard , Kleiner David E. , Gorden Phillip
Published: June 2005

BACKGROUND

Malignant insulinoma occurs in a few patients with insulinoma. Due to the small sample of patients, there are little data regarding their clinical manifestation as well as the preferred treatment modalities. The aims of the current study were to summarize the National Institutes of Health experience during the last two decades and to conduct a critical review of the current literature.

METHODS

The authors identified 10 patients with metastatic insulinoma.

RESULTS

The patients presented with four patterns of clinical behavior. First, four patients presented with lymph node metastasis and, after surgical excision, maintained a prolonged tumor‐free survival. Second, four patients presented with metastatic disease to the liver, which appeared years after the initial diagnosis and presumed curative surgery. Third, one patient presented with a large α‐fetoprotein‐secreting liver mass. Finally, 9 of the 10 patients had a prolonged survival. Various treatment modalities were used to control hypoglycemia. Short‐term benefits were most often achieved with embolization and diazoxide. Less successful modalities included radiofrequency ablation, radical debulking surgery, verapamil therapy, octreotide therapy, and chemotherapy.

CONCLUSIONS

The current study, as well as others, suggested that metastatic insulinoma may have a variable natural history. After the initial surgical resection, the biology of the tumor, rather than any treatment modality, was most likely the major determinant of long‐term survival. Cancer 2005. © Published 2005 American Cancer Society.
The natural history of breast carcinoma in patients with ≥ 10 metastatic axillary lymph nodes before and after the advent of adjuvant therapy
Authors: Montero Alberto J. , Rouzier Roman , Lluch Ana , Theriault Richard L. , Buzdar Aman U. , Delaloge Suzette , Bermejo Begoñia , Le Monique , Kau Shu‐Wan , Dunant Ariane , Arriagada Rodrigo , Spielmann Marc , Garcia‐Conde Javier , Sahin Aysegul A. , Singletary Sonja E. , Hortobagyi Gabriel N. , Valero Vicente
Published: June 2005

BACKGROUND

The majority of patients with breast carcinoma with ≥ 10 metastatic axillary lymph nodes (ALNs) develop recurrent disease within 5 years from diagnosis. The purpose of the current study, performed retrospectively, was to characterize the natural history of this subset of patients, both before and after the advent of adjuvant anthracycline‐based chemotherapy and tamoxifen.

METHODS

Retrospectively, patients with primary breast carcinoma (N= 882) with ≥ 10 metastatic ALNs, treated between 1954 and 1998, were selected from 3 institutions: The University of Texas M. D. Anderson Cancer Center (Houston, TX); the Institut Gustave Roussy (Villejuif, France); and Hospital Clinico Universitario (Valencia, Spain). All patient data had been registered prospectively in clinical databases. One group consisted of 314 patients treated with locoregional therapy alone (no adjuvant therapy) from 1954 to 1983. The second group included 568 patients who received adjuvant anthracycline‐based chemotherapy between 1974 and 1998 with or without adjuvant tamoxifen.

RESULTS

The median follow‐up time was 140 months. Disease‐free survival rates at 15 and 20 years for the no adjuvant therapy and adjuvant therapy groups were 17% and 16% versus 26% and 24%, respectively. The overall survival rates at 20 years for the no adjuvant therapy and the adjuvant therapy groups were 9% and 21%, respectively. By multivariate analysis, the independent factors associated with survival in the adjuvant therapy group were tumor size and the number of metastatic lymph nodes.

CONCLUSIONS

The retrospective analysis suggested that adjuvant anthracycline‐based chemotherapy and hormonal therapy have altered the natural history in this high‐risk group of patients. However, despite such improvements, survival rates remained low, and innovative therapeutic approaches are, therefore, needed to improve clinical outcomes. Cancer 2005. © 2005 American Cancer Society.
The mesenchymal cell, its role in the embryo, and the remarkable signaling mechanisms that create it
Authors: Hay Elizabeth D.
Published: June 2005

This review centers on the role of the mesenchymal cell in development. The creation of this cell is a remarkable process, one where a tightly knit, impervious epithelium suddenly extends filopodia from its basal surface and gives rise to migrating cells. The ensuing process of epithelial–mesenchymal transformation (EMT) creates the mechanism that makes it possible for the mesenchymal cell to become mobile, so as to leave the epithelium and move through the extracellular matrix. EMT is now recognized as a very important mechanism for the remodeling of embryonic tissues, with the power to turn an epithelial somite into sclerotome mesenchyme, and the neural crest into mesenchyme that migrates to many targets. Thus, the time has come for serious study of the underlying mechanisms and the signaling pathways that are used to form the mesenchymal cell in the embryo. In this review, I discuss EMT centers in the embryo that are ready for such serious study and review our current understanding of the mechanisms used for EMT in vitro, as well as those that have been implicated in EMT in vivo. The purpose of this review is not to describe every study published in this rapidly expanding field but rather to stimulate the interest of the reader in the study of the role of the mesenchymal cell in the embryo, where it plays profound roles in development. In the adult, mesenchymal cells may give rise to metastatic tumor cells and other pathological conditions that we will touch on at the end of the review. Developmental Dynamics 233:706–720, 2005. © 2005 Wiley‐Liss, Inc.
Fly Six‐type homeodomain proteins Sine oculis and Optix partner with different cofactors during eye development
Authors: Kenyon Kristy L. , Li Dan Jun , Clouser Christopher , Tran Susan , Pignoni Francesca
Published: June 2005

Two members from the Six class of homeobox transcription factors, Sine oculis (SO) and Optix, function during development of the fly visual system. Differences in gain‐of‐function phenotypes and gene expression suggest that these related factors play distinct roles in the formation of the fly eye. However, the molecular nature of their functional differences remains unclear. In this study, we report the identification of two novel factors that participate in specific partnerships with Sine oculis and Optix during photoreceptor neurons formation and in eye progenitor cells. This work shows that different cofactors likely mediate unique functions of Sine oculis and Optix during the development of the fly eye and that the repeated requirement for SO function at multiple stages of eye development reflects the activity of different SO–cofactor complexes. Developmental Dynamics 234:497–504, 2005. © 2005 Wiley‐Liss, Inc.
Microarray analysis of zebrafish cloche mutant using amplified cDNA and identification of potential downstream target genes
Authors: Qian Feng , Zhen Fenghua , Ong Chinthing , Jin Suk‐Won , Meng Soo Hui , Stainier Didier Y.R. , Lin Shuo , Peng Jinrong , Wen Zilong
Published: June 2005

Zebrafish is an excellent model organism for studying vertebrate development and human disease. With the availability of increased numbers of zebrafish mutants and microarray chips, gene expression profiling has become a powerful tool for identification of downstream target genes perturbed by a specific mutation. One of the obstacles often encountered, however, is to isolate large numbers of zebrafish mutant embryos that are indistinguishable in morphology from the wild‐type siblings for microarray analysis. Here, we report a method using amplified cDNA derived from five embryos for gene expression profiling of the 18‐somite zebrafish cloche (clo) mutant, in which development of hematopoietic and endothelial lineages is severely impaired. In total, 31 differentially expressed target genes are identified, of which 13 have not been reported previously. We further determine that of these 13 new targets, 8 genes, including coproporphyrinogen oxidase (cpo), carbonic anhydrase (cahz), claudin g (cldn g), zinc‐finger–like gene 2 (znfl2), neutrophil cytosol factor 1 (ncf1), matrix metalloproteinase 13 (mmp13), dual specificity phosphatase 5 (dusp5), and a novel gene referred as zebrafish vessel‐specific gene 1 (zvsg1) are predominantly expressed in hematopoietic and endothelial cells. Comparative analysis demonstrates that this method is comparable and complementary to that of the conventional approach using unamplified sample. Our study provides valuable information for studying hematopoiesis and vessel formation. The method described here offers a powerful tool for gene expression profiling of zebrafish mutants in general. Developmental Dynamics 233:1163–1172, 2005. © 2005 Wiley‐Liss, Inc.
Neonatal dexamethasone induces premature microvascular maturation of the alveolar capillary network
Authors: Roth‐Kleiner Matthias , Berger Thomas M. , Tarek Mojmir R. , Burri Peter H. , Schittny Johannes C.
Published: June 2005

Postnatal glucocorticoid treatment of preterm infants was mimicked by treating newborn rats with dexamethasone (0.1–0.01 μg/g, days 1–4). This regimen has been shown to cause delayed alveolarization. Knowing that microvascular maturation (transformation of double‐ to single‐layered capillary networks in alveolar septa) and septal thinning prevent further alveolarization, we measured septal maturation on electron photomicrographs in treated and control animals. In treated rats and before day 10, we observed a premature nonreversing microvascular maturation and a transient septal thinning, which both appeared focally. In vascular casts of both groups, we observed contacts between the two capillary layers of immature alveolar septa, which were predictive for capillary fusions. Studying serial electron microscopic sections of human lungs, we were able to confirm the postulated fusion process for the first time. We conclude that alveolar microvascular maturation indeed occurs by capillary fusion and that the dexamethasone‐induced impairment of alveolarization is associated with focal premature capillary fusion. Developmental Dynamics 233:1261–1271, 2005. © 2005 Wiley‐Liss, Inc.
Chk2/Cds1 protein kinase blocks apoptosis during early development of Xenopus laevis
Authors: Wroble Brian N. , Sible Jill C.
Published: June 2005

Early Xenopus laevis embryos possess cell cycles that do not arrest at checkpoints in response to damaged DNA. At the midblastula transition (MBT), embryos with damaged DNA undergo apoptosis. After the MBT, DNA damage triggers cell cycle arrest rather than apoptosis. The transition from checkpoint‐unregulated to checkpoint‐regulated cycles makes Xenopus embryos compelling for studying mechanisms regulating response to genomic damage. The DNA damage checkpoint is mediated by the Chk2/Cds1 kinase. Conflicting evidence implicates Chk2 as an inhibitor or promoter of apoptosis. To better understand the developmental function of Chk2, we expressed wild‐type (wt) and dominant‐negative (DN) Chk2 in Xenopus embryos. Wt‐Chk2 created a pre‐MBT checkpoint due to degradation of Cdc25A and phosphorylation of cyclin‐dependent kinases. Embryos expressing DN‐Chk2 developed normally until gastrulation and then underwent apoptosis. Conversely, low doses of wt‐Chk2 blocked radiation‐induced apoptosis. Therefore, Chk2 operates at a switch between cell cycle arrest or apoptosis in response to genomic assaults. Developmental Dynamics 233:1359–1365, 2005. © 2005 Wiley‐Liss, Inc.
Identification of a gene required for de novo DNA methylation of the zebrafish no tail gene
Authors: Shimoda Nobuyoshi , Yamakoshi Kimi , Miyake Akimitsu , Takeda Hiroyuki
Published: June 2005

The zebrafish no tail gene (ntl) is indispensable for tail and notochord development. We have shown previously that ntl is de novo methylated during early embryogenesis. To find the gene that de novo methylates ntl and understand the meaning of this methylation, we cloned seven genes that encode the conserved catalytic domain of methyltransferases. We found that injection of antisense morpholino oligonucleotides against one of them, termed dnmt7, into eggs significantly reduced the level of ntl methylation, although no apparent phenotype was induced by the injection. Inhibition of Dnmt7 activity did not change the level of genome‐wide methylation nor did it affect de novo methylation of injected plasmid DNA, indicating that Dnmt7 specifically methylates ntl in the genome. Developmental Dynamics 233:1509–1516, 2005. © 2005 Wiley‐Liss, Inc.
Osteopontin and related SIBLING glycoprotein genes are expressed by Sertoli cells during mouse testis development
Authors: Wilson Megan J. , Liaw Lucy , Koopman Peter
Published: June 2005

Matrix proteins play important roles in tissue morphogenesis. We have studied the expression of genes encoding the related SIBLING glycoproteins osteopontin (OPN), bone sialoprotein (BSP), and dentin matrix protein (DMP) during the development of male and female gonads during mouse embryogenesis. Opn mRNA was expressed specifically by Sertoli cells of the developing testis cords, in the mesonephric tubules of both sexes, and, transiently, in the Müllerian ducts of both sexes, as determined by whole‐mount and section in situ hybridization. OPN protein was detected in the cytoplasm of Sertoli cells and luminal cells of the mesonephric tubules, with small amounts associated with the plasma membrane of germ cells. We found no defects in developing testes of Opn−/− mice using a range of cell type‐specific markers, suggesting that other SIBLING proteins may function in testis development. Dmp and Bsp mRNA was also expressed in the developing testis cords, supporting the view that all three SIBLING proteins may contribute to testis differentiation. Developmental Dynamics 233:1488–1495, 2005. © 2005 Wiley‐Liss, Inc.
Trialkoxysilyl‐Functionalized Silver(I) Carboxylates: New Building Blocks for the Synthesis of Immobilizable and Immobilized Homogeneous Catalysts
Authors: Vehlow Kati , Köhler Katrin , Blechert Siegfried , Dechert Sebastian , Meyer Franc
Published: June 2005

Partly fluorinated trialkoxysilyl‐substituted carboxylic acids (RO)3Si(CH2)3N(R')C(O)(CF2)3COOH (3a: R = Et, R' = H; 3b: R = R' = Me) have been prepared in a straightforward synthesis from the respective trialkoxysilyl‐substituted primary and secondary amines and hexafluoroglutaric anhydride. Treatment with silver(I) oxide yields the corresponding silver carboxylates 4a,b which have been thoroughly characterized in solution and in the solid state, including an X‐ray crystallographic analysis of 4a. The molecular structure of 4a consists of archetypal carboxylate‐bridged disilver(I) pairs with a strong closed‐shell Ag–Ag (d10–d10) interaction and a unique intramolecular bond between a silyl ether group and the metal ion. In addition the amide oxygen atoms are involved in H‐bonding and in intermolecular silver coordination, giving rise to an unusual two‐dimensional network structure. Silyl‐free acid iPr2NC(O)(CF2)3COOH (5) and its silver salt 6 have been prepared and structurally characterized for comparison. It is shown that the trialkoxysilyl tail in 4a,b allows for convenient attachment of these silver complexes to silica surfaces, as is corroborated by DRIFT measurements. The immobilized silver carboxylates 7a,b exhibit remarkable stability and are expected to open an easy access to a wide variety of SiO2‐grafted transition metal catalysts via transfer of the carboxylate ligand in simple exchange reactions. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005)
Tautomeric Self‐Dimerization and Molecular Recognition Properties of2‐Aminopyrimidinone Derivatives as Triple Hydrogen‐Bonding Modules in Molecular Assemblies
Authors: Abe Hajime , Takase Masayoshi , Doi Yasuhiro , Matsumoto Shinya , Furusyo Masaru , Inouye Masahiko
Published: June 2005

A triple hydrogen‐bonding module based on 6‐alkynyl‐2‐amino‐3H‐pyrimidin‐4‐one was developed such as for self‐dimerization and for nucleobase recognition processes. The strength of the module for the self‐dimerization was determined by NMR and fluorimetric analyses in chloroform (ΔG298 = –22 to –23 kJ/mol). DFT calculations and X‐ray structure analysis showed that the self‐dimerization consists of the three‐point hydrogen‐bonding including two kinds of tautomers of the module in an ADD·DAA mode. Selective recognition of the module for a cytidine derivative was also observed, and the free energy change for the complexation (ΔG298 = –31 kJ/mol) is one of the highest values among triple hydrogen‐bonded complexes so far reported. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005)
Synthesis and Comparative Glycosidase Inhibitory Properties of Reducing Castanospermine Analogues
Authors: Díaz Pérez Paula , García‐Moreno M. Isabel , Ortiz Mellet Carmen , García Fernández José M.
Published: June 2005

The feasibility of the intramolecular nucleophilic addition of the nitrogen atom in cyclic (thio)carbamates with a pseudo‐C‐nucleoside structure to the masked carbonyl group in aldose precursors in the synthesis of reducing (i.e., 5‐hydroxy)6‐oxaindolizidine frameworks is illustrated by the preparation of the 6‐epi, 7‐epi, 8‐epi and 6,8a‐di‐epi diastereomers of the potent glycosidase inhibitor (+)‐castanospermine. In all cases, the increased anomeric effect caused by the high sp2 character of the pseudoamide‐type nitrogen atom resulted in the pseudoanomeric hydroxy group being anchored in an axial orientation in aqueous solution, as in the aglycons in α‐glycosides. These analogs of the natural alkaloid showed a higher selectivity in the inhibition of α‐glucosidases. Structure/glycosidase inhibitory activity studies indicated that inversion of any hydroxy group resulted in a dramatic decrease in the inhibition potency, confirming the critical importance of a correct hydroxylation profile. In the case of (+)‐8‐epi‐6‐oxacastanospermine derivatives, with a hydroxylation profile with a structural complementarity to that of D‐galactose, a moderate but very selective inhibition of α‐galactosidase was observed, supporting the importance of a defined configuration at pseudoanomeric centres for anomeric specificity. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005)
Highly Methylated Purines and Purinium Salts as Analogues of Heteromines
Authors: Hocek Michal , Pohl Radek , Císařová Ivana
Published: June 2005

Three new unsubstituted or N‐methylated derivatives of 2‐amino‐6,7,9‐trimethylpurinium iodides were prepared by quaternization of the corresponding 2‐amino‐6,7‐dimethylpurines. These intermediates were synthesized either by Pd‐catalysed cross‐coupling of 2‐amino‐6‐chloro‐9‐methylpurine with trimethylaluminium or by regioselective Fe‐catalysed cross‐coupling of 2,6‐dichloro‐9‐methylpurine with methylmagnesium chloride, followed by amination. Both the title purinium salts and the purine intermediates were studied by 15N NMR, and one example of the purinium salts also by X‐ray diffraction. None of the compounds exerted significant cytostatic activity. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005)
Detection and separation of nucleoside‐5'‐monophosphates of DNA by conjugation with the fluorescent dye BODIPY and capillary electrophoresis with laser‐induced fluorescence detection
Authors: Cornelius Michael , Wörth Christian G. C. T. , Kliem Hans‐Christian , Wiessler Manfred , Schmeiser Heinz H.
Published: June 2005

We investigated the separation and detection of the 5'‐monophosphates of 2'‐deoxynucleosides selectively conjugated with 4,4‐difluoro‐5,7‐dimethyl‐4‐bora‐3a,4a‐diaza‐s‐indacene‐3‐propionyl ethylene diamine hydrochloride (BODIPY FL EDA) at the 5'‐phosphate group using capillary electrophoresis with laser‐induced fluorescence detection (CE‐LIF). BODIPY conjugates of the four common deoxynucleoside‐5'‐monophosphates (2'‐deoxyguanosine‐5'‐monophosphate, 2'‐deoxyadenosine‐5'‐monophosphate, 2'‐deoxycytidine‐5'‐monophosphate, and thymidine‐5'‐monophosphate) were prepared and subjected to CE‐LIF to serve as standard compounds for peak assignment and to develop separation conditions for the analysis of DNA. BODIPY conjugates were detected and resolved by CE‐LIF after digestion of DNA or an oligonucleotide to 5'‐monophosphates by nuclease P1 (NP 1) and fluorescence labeling without further purification step. Comparative analyses of calf‐thymus DNA digested either with micrococcal nuclease/spleen phosphodiesterase to 3'‐monophosphates or with NP 1 to 5'‐monophosphates showed that both versions of the fluorescence postlabeling assay were equally efficient and sensitive. Moreover, using the same assay, 2'‐deoxyuridine and 2'‐deoxy‐5methylcytidine were identified in bisulfite treated DNA after NP 1 digestion indicating that fluorescence postlabeling of 2'‐deoxyribonucleoside‐5'‐monophosphates with BODIPY FL EDA and detection by CE‐LIF has the potential to determine DNA damage and genomic DNA methylation.
The impact of epistemic uncertainty on an earthquake loss model
Authors: Crowley Helen , Bommer Julian J. , Pinho Rui , Bird Juliet
Published: June 2005

Models capable of estimating losses in future earthquakes are of fundamental importance for emergency planners, for the insurance and reinsurance industries, and for code drafters. Constructing a loss model for a city, region or country involves compiling databases of earthquake activity, ground conditions, attenuation equations, building stock and infrastructure exposure, and vulnerability characteristics of the exposed inventory, all of which have large associated uncertainties. Many of these uncertainties can be classified as epistemic, implying—at least in theory—that they can be reduced by acquiring additional data or improved understanding of the physical processes. The effort and cost involved in refining the definition of each component of a loss model can be very large, for which reason it is useful to identify the relative impact on the calculated losses due to variations in these components. A mechanically sound displacement‐based approach to loss estimation is applied to a test case of buildings along the northern side of the Sea of Marmara in Turkey. Systematic variations of the parameters defining the demand (ground motion) and the capacity (vulnerability) are used to identify the relative impacts on the resulting losses, from which it is found that the influence of the epistemic uncertainty in the capacity is larger than that of the demand for a single earthquake scenario. Thus, the importance of earthquake loss models which allow the capacity parameters to be customized to the study area under consideration is highlighted. Copyright © 2005 John Wiley & Sons, Ltd.
The interactive online SKY/M‐FISH & CGH Database and the Entrez Cancer Chromosomes search database: Linkage of chromosomal aberrations with the genome sequence
Authors: Knutsen Turid , Gobu Vasuki , Knaus Rodger , Padilla‐Nash Hesed , Augustus Meena , Strausberg Robert L. , Kirsch Ilan R. , Sirotkin Karl , Ried Thomas
Published: June 2005

To catalog data on chromosomal aberrations in cancer derived from emerging molecular cytogenetic techniques and to integrate these data with genome maps, we have established two resources, the NCI and NCBI SKY/M‐FISH & CGH Database and the Cancer Chromosomes database. The goal of the former is to allow investigators to submit and analyze clinical and research cytogenetic data. It contains a karyotype parser tool, which automatically converts the ISCN short‐form karyotype into an internal representation displayed in detailed form and as a colored ideogram with band overlay, and also has a tool to compare CGH profiles from multiple cases. The Cancer Chromosomes database integrates the SKY/M‐FISH & CGH Database with the Mitelman Database of Chromosome Aberrations in Cancer and the Recurrent Chromosome Aberrations in Cancer database. These three datasets can now be searched seamlessly by use of the Entrez search and retrieval system for chromosome aberrations, clinical data, and reference citations. Common diagnoses, anatomic sites, chromosome breakpoints, junctions, numerical and structural abnormalities, and bands gained and lost among selected cases can be compared by use of the “similarity” report. Because the model used for CGH data is a subset of the karyotype data, it is now possible to examine the similarities between CGH results and karyotypes directly. All chromosomal bands are directly linked to the Entrez Map Viewer database, providing integration of cytogenetic data with the sequence assembly. These resources, developed as a part of the Cancer Chromosome Aberration Project (CCAP) initiative, aid the search for new cancer‐associated genes and foster insights into the causes and consequences of genetic alterations in cancer. Published 2005 Wiley‐Liss, Inc.
A Protein Appears in a Different Light
Authors: Herzog Volker , Kirfel Gregor , Schmitz Anton , Tikkanen Ritva
Published: June 2005

APP is assumed to play a role in causing Alzheimer′s disease. Its biological functions in the human body are currently unknown but of increasing interest in basic research, especially in investigating the process of wound healing
Sperm on a Scented Trail
Authors: Hatt Hanns , Spehr Marc
Published: June 2005

Messages from the realm of scent: human sperm have a sense of smell too. This means that chemical scents play a major role in reproduction
Federalism in the Service of Science
Authors: Hopt Klaus J.
Published: June 2005

A pact for research can promote freedom and self‐governance on the international playing field
Pathways as “Silent Guides” to the Past
Authors: Hallmann Heinz W. , Forner Jörg‐Ulrich
Published: June 2005

Paths shape the appearance of parks and gardens. This was already realised by the pioneers of landscape gardening. The reconstruction of historical paths today can be extremely revealing – and not just from the point of view of historical preservation
In vivo imaging of neuromodulatory synaptic transmission using PET: A review of relevant neurophysiology
Authors: Fisher Ronald E. , Morris Evan D. , Alpert Nathaniel M. , Fischman Alan J.
Published: May 2005

Recent data from positron emission tomography (PET) imaging studies suggest the possibility of studying synaptic transmission in vivo in humans. The approach will require a synthesis of two established techniques: brain activation studies (conventionally performed by measuring regional cerebral blood flow or metabolism) and neurotransmitter receptor imaging (using radiolabelled ligands that bind to specific neuroreceptors). By comparing neuroreceptor binding in subjects at rest and while performing an activation task, it may be possible to determine whether a particular neurotransmitter is involved in performance of the task. The underlying principle is that endogenous neurotransmitter competes with the injected radioligand for the same receptors, thereby inhibiting ligand binding. This effect will be even more pronounced during activation, as the synaptic concentration of transmitter rises. Thus, activation of a specific neurotransmitter will be detected as a decrease in specific binding of the radioligand. In this paper we review neurophysiological and biochemical literature to estimate the endogenous neurotransmitter concentration changes that will be expected to occur during an activation task, using the dopamine system as an example. We calculate that the average synaptic dopamine concentration is ≈ 100 nM and that it approximately doubles during activation. This, along with consideration of the concentration of radioligand and affinities of the ligand and dopamine for dopamine receptors, suggests that physiological activation of a specific neurotransmitter system is likely to be detectable with PET. © 1995 Wiley‐Liss, Inc.