bluuebunny/crossref_metadata_2025 huggingface dataset:
Continued proteomic analysis of Mycobacterium leprae subcellular fractions
Authors: Marques Maria Angela M. , Espinosa Benjamin J. , Xavier da Silveira Erika K. , Pessolani Maria Cristina V. , Chapeaurouge Alex , Perales Jonas , Dobos Karen M. , Belisle John T. , Spencer John S. , Brennan Patrick J.
Published: August 2004

Recently the sequence of the Mycobacterium leprae chromosome, the only known obligate intracellular mycobacterium, was completed. It has a dramatic reduction in functional genes, with a coding capacity of only 49.5%, the lowest one so far observed among bacterial genomes. The leprosy bacillus seems to preserve a minimal set of genes that allows its survival in the host. The identification of genes that are actually expressed by the bacterium is of high significance in the context of mycobacterial pathogenesis. In this current study, a proteomic approach was undertaken to identify the proteins present in the soluble/cytosol and membrane subcellular fractions obtained from armadillo derived M. leprae. Proteins from each fraction were separated by two‐dimensional gel electrophoresis (2‐DE) and identified by mass spectrometry. A total of 147 protein spots were identified from 2‐DE patterns and shown to comprise products of 44 different genes, twenty eight of them corresponding to new proteins. Additionally, two highly basic proteins (with pI > 10.0) were isolated by heparin affinity chromatography and identified by N‐terminal sequencing. This study constitutes the first application of proteomics to a host‐derived Mycobacterium.
Direct incorporation of gaseous carbon dioxide into solid‐state copolymer containing oxirane and quaternary ammonium halide structure as self‐catalytic function
Authors: Ochiai Bungo , Iwamoto Tokinori , Miyagawa Toyoharu , Nagai Daisuke , Endo Takeshi
Published: August 2004

We established a self‐catalyst system for solid phase incorporation of gaseous carbon dioxide into terpolymers prepared by polymerization of glycidyl methacrylate, N‐benzyl‐N‐[2‐(methacryrolroxy)ethyl]‐N,N‐dimethylammonium bromide, and methyl methacrylate. Terpolymer composition affected the incorporation behavior where the terpolymer with higher oxirane content exhibited higher efficiency of carbon dioxide incorporation. © 2004 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 42: 4941–4947, 2004
Photoinitiators with functional groups. VII. Covalently bonded camphorquinone—amines
Authors: Ullrich G. , Herzog D. , Liska R. , Burtscher P. , Moszner N.
Published: August 2004

Camphorquinone (CQ), a widely used photoinitiator (PI) in dental applications, was covalently bonded to aromatic amines to enhance the rate of electron and proton transfer effect due to the close vicinity of the diketone and the amine group. 10‐bromocamphorquinone and 10‐bromomethylcamphorquinone were selected as suitable precursors for esterification with the carboxyl group containing aromatic amines based on 4‐dimethylaminobenzoic acid. Properties of the new photoinitiating systems were investigated by UV spectroscopy and differential scanning photocalorimetry in lauryl acrylate. Compared to physical mixtures, in all cases similar or even better performance was obtained. Surprisingly, 10‐acetyl derivatives 7–9 and 18 especially, were found to be highly reactive. Compared to CQ/ethyl 4‐dimethylaminobenzoate, the rate of photopolymerization was increased by a factor of up to 2. Intramolecular reaction was confirmed by photo‐differential scanning calorimetry experiments with varying PI concentrations. © 2004 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 42: 4948–4963, 2004
Dependence of the kinetics of the anionic polymerization of methyl methacrylate on the concentration in active centers
Authors: Lavaud François , Fontanille Michel , Gnanou Yves
Published: August 2004

Studies on the anionic polymerization of methyl methacrylate in tetrahydrofuran and in the presence of sparteine have revealed a beneficial effect due to this additive, resulting in a decrease in the extent of termination. Better control of the definition of the polymers formed can thus be achieved in the presence of this additive. On the other hand, macromolecular engineering requires a range of active species concentrations lower than 10−3 mol L−1 and particularly the synthesis of polymers of high molar masses. For a better understanding of the mechanism of chain growth under such concentration conditions, the kinetics of polymerization have been investigated with a technique based on adiabatic calorimetry. Sparteine has been found to lack sufficient cation‐binding power to prevent the propagating enolate ion pairs from aggregating. The rate constant of propagation of nonaggregated species has been estimated, as well as the aggregation constant of equilibrium. For very low initiator concentrations, termination reactions have been shown to profoundly alter the control of the polymerization and to prevent a quantitative monomer conversion. Theoretical maximal conversions have been calculated from kinetic data and compare well with the experimental values. © 2004 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 42: 4964–4975, 2004
Quantum hydrodynamics: Mixed states, dissipation, and a new hybrid quantum‐classical approach
Authors: Burghardt Irene , Møller Klaus B. , Parlant Gérard , Cederbaum Lorenz S. , Bittner Eric R.
Published: August 2004

The formulation of quantum hydrodynamics for mixed states provides a complement, in a quantum‐statistical context, to its pure‐state “Bohmian mechanics” analogue. We summarize our recent work in this area, focusing on two key aspects. We first describe the formulation of a generalized hydrodynamic force, which includes the effects of thermal fluctuations and “quantum fluctuations” and thus determines the time evolution under the influence of dissipation. Second, we introduce a mixed hydrodynamic–Liouville space representation in terms of partial moments, as applied in the context of coupled electronic states and mixed quantum‐classical dynamics. © 2004 Wiley Periodicals, Inc. Int J Quantum Chem, 2004
Theoretical studies on magnetic interaction in one‐dimensional spin chains of hydrogen atoms (Hn) and copper bromide (CunBrm)
Authors: Kawakami Takashi , Taniguchi Takeshi , Kitagawa Yasutaka , Matsumoto Takuya , Kamada Yohsuke , Sugimoto Toyonari , Okumura Mitsutaka , Yamaguchi Kizashi
Published: August 2004

Theoretical calculations of ab initio molecular orbital and density functional theory calculations were carried out in order to investigate magnetic interaction in one‐dimensional spin chains. Effective exchange integral (Jab) values are useful parameters in studying magnetic interaction in spin systems. Chemical indices also were evaluated to represent stability of broken symmetry spin. For one set of spin chains, alignment of hydrogen atoms as the most simple organic cluster was employed. Number of H atoms in employed models is two and 50 with interatomic distance 2.1 Å. In addition, copper bromide chains (CunBrm) were also studied. Simple molecules Br2‐Cu‐Br2‐Cu‐Br2 (without apical‐Br) and Br2‐CuBr‐Br2‐CuBr‐Br2 (with apical‐Br) were employed for simple model structure. Four parameters (r, a, b, and c) can fix the structure and study parameter dependency of Jab values. For experimental studies, Sugimoto and his coworkers have reported synthesis and experimental studies for complex of both CunBrm chains and TTF‐derivative donor. Magnetic behavior in only CunBrm chains was investigated in detail by several ab initio methods. © 2004 Wiley Periodicals, Inc. Int J Quantum Chem, 2004
Nicht alle Eier in einen Korb! ‐ Einsatzmöglichkeiten von Modellen des Risikomanagements in der empirischen Marketingforschung
Authors: Kriete Thomas
Published: August 2004

Im Rahmen der Marketingforschung stellt die Suche nach einem optimalen Produktportfolio ein wesentliches Problem dar. Mit Hilfe von Modellen aus dem Risikomanagement werden am Beispiel von Porsche die Auswirkungen von Erweiterungen des Produktportfolios in der Vergangenheit ebenso wie mögliche künftige Erweiterungen analysiert. Danach stellte der Einstieg in das Segment Geländewagen mit dem Porsche Cayenne aus Rendite/Risiko‐Überlegungen eine deutliche Verbesserung des Produktportfolios dar. Für eine weitere Expansion bietet das Segment Mini die beste Rendite/Risiko‐Struktur.
Bank of Corruption and Criminal Incompetence ‐ Der Zusammenbruch der BCCI
Authors: Romeike Frank
Published: August 2004

Der Chef des CIA bezeichnete die Bank of Credit and Commerce International (BCCI) einmal als Bank of Crooks and Criminals . Das Nachrichtenmagazin TIME nannte sie die schmutzigste aller Banken . In Bankenkreisen wurde das Geldhaus häufig als Bank of Corruption and Criminal Incompetence bezeichnet. Wie auch immer: wenn man die Liste der Kunden überfliegt, wird einem schnell klar, dass bei der BCCI jeder über ein Konto verfügte, der in den großen Dunkel‐meister‐ Geschäften dieser Welt einen Namen hatte: von Escobar über Noriega, das Medellin‐Kartell, den Opiumkönig Khun Sa, der CIA bis zu Qadeer Khan, dem Vater der islamischen Atombombe. Die Bank war vor allem eine Annah‐mestelle für die Gelder der Drogenmafia und der diversen Terrornetzwerke auf diesem Planeten. Sie operierte in 73 Ländern und verwaltete Gelder in Höhe von etwa 30 Milliarden US‐Dollar. Ursprünglich geplant war das Institut mit seinem intransparenten Beteiligungsgeflecht auch als Gegengewicht zu den Investmentbanken an der Wall Street. Bekannt war die BCCI unter anderem für ihre Politik der Blankokredite.
Verrated und Verkauft? ‐ Rating als neues Risiko für den Mittelstand
Authors: Mattern Harald
Published: August 2004

Schon bisher haben Banken vor einer Kreditgewährung und während der Laufzeit eine Überprüfung des Engagements durchzuführen, um festzustellen, wie wahrscheinlich die planmäßige Rückzahlung ist. Das ist also nicht neu. Neu im Rahmen des Rating ist die Systematik, mit der eine große Zahl von Einzelfak‐toren zu bewerten ist und die Wirkungen, die von solch einer standardisierten Betrachtungsweise ausgehen. Neu ist vor allem für den mittelständischen Unternehmer, dass er viel mehr Informationen vorlegen und rechtfertigen muss. Neu ist für ihn, dass er sich mit Zusammenhängen und Wirkungen auseinandersetzen muss, die ihm in der Vergangenheit so nicht bewusst waren und die er vor allem nicht systematisch durchleuchtet hat. Insbesondere viele kleinere Unternehmer werden aufgrund ihrer Vor‐ und Ausbildung dazu nicht in der Lage sein, obwohl das bisherige intuitive Handeln zu durchaus ansehnlichen Ergebnissen geführt hat.
Vorsicht Hochspannung! ‐ Risikomanagement in Energiemärkten (Teil II) Modellierung von Strompreisen
Authors: Trück Stefan , Weron Rafal
Published: August 2004

Nachdem der erste Teil der Serie [siehe RISKNEWS 03/2004, S. 64‐69] eine Einführung in den Stromhandel in Deutschland gab und Besonderheiten im Preisverhalten auf Strommärkten (wie etwa Saisonalitäten, hohe Volatilitäten, Mean‐Reversion‐Verhalten) erläutert wurden, werden im zweiten Teil Möglichkeiten der Modellierung von Strompreisen vorgestellt.
Framing new research in science literacy and language use: Authenticity, multiple discourses, and the “Third Space”
Authors: Wallace Carolyn S.
Published: August 2004

This article presents a theoretical framework in the form of a model on which to base research in scientific literacy and language use. The assumption guiding the framework is that scientific literacy is comprised of the abilities to think metacognitively, to read and write scientific texts, and to apply the elements of a scientific argument. The framework is composed of three theoretical constructs: authenticity, multiple discourses, and Bhabha's Third Space. Some of the implications of the framework are that students need opportunities to (a) use scientific language in everyday situations; (b) negotiate readily among the many discourse genres of science; and (c) collaborate with teachers and peers on the meaning of scientific language. These ideas are illustrated with data excerpts from contemporary research studies. A set of potential research issues for the future is posed at the end of the article. © 2004 Wiley Periodicals, Inc. Sci Ed 88:901–914, 2004
Ultrasound training: the virtual patient
Authors: Heer I. M. , Middendorf K. , Müller‐Egloff S. , Dugas M. , Strauss A.
Published: August 2004

Objective

To evaluate an ultrasound training system designed to standardize teaching and learning of gynecological sonography using a virtual model.

Methods

The ‘virtual patient’ was based on a three‐dimensional freehand ultrasound system that allows two‐dimensional sonographic offline investigations of previously recorded cases, imitating a real gynecological scan. In the first test phase designed to check the congruence of real and virtual scans, 25 doctors experienced in ultrasound examined three virtual cases. During the second test phase we assessed whether training with the virtual patient helped to establish a satisfactory practical knowledge of gynecological ultrasound. This phase was carried out with 24 medical students without ultrasound experience.

Results

All 25 doctors successfully investigated the three cases and generated an accurate diagnosis for the first and second cases. In the third case 14 doctors made the correct diagnosis (uterus bicornis). The measurements of endometrial thickness and the diameter of a fibroid yielded acceptable results compared with the original investigation. After a short standardized video‐based instruction, all 24 medical students were able to perform a basic transvaginal scan and to inspect the uterus, ovaries and the urinary bladder. Measurements of endometrial thickness by all students deviated minimally from the actual measurement.

Conclusions

Training with the virtual patient appears to be comparable to performing a live gynecological ultrasound investigation and allows standardized ultrasound teaching and learning. Copyright © 2004 ISUOG. Published by John Wiley & Sons, Ltd.
Two‐ and three‐dimensional sonographic assessment of the fetal face. 2. Analysis of cleft lip, alveolus and palate
Authors: Rotten D. , Levaillant J. M.
Published: August 2004

Objectives

To describe the sonographic appearance of cleft lip with or without cleft palate (CL ± P) using two‐dimensional and three‐dimensional (3D) ultrasound imaging. Also, to evaluate the accuracy of ultrasound to delineate with precision the bony extent of facial clefts, i.e. to differentiate clefts limited to the lips, or extending to the alveolus/premaxilla or the secondary palate.

Methods

This was a retrospective study based on the examination of fetuses diagnosed with an isolated CL ± P. Cases included were either discovered at systematic screening or referred for further investigation. Clefts were characterized by their precise anatomical location and extent. The defect could include a cleft lip (CL), a cleft alveolus (CA), or a cleft of the secondary palate (CSP).

Results

We analyzed 96 cases of CL ± P. The mean gestational age at examination was 28.2 ± 4.1 weeks. The sonographic appearance of CL, CA, and CSP was depicted. Strict concordance of the sonographic report with the anatomical defect was present in 84 cases (87.5%). In eight cases, the severity of the cleft was underestimated: three cases of CA, four of CA + CSP and one of CSP were missed. In four cases, the cleft was overestimated as CA was incorrectly suspected.

Conclusions

Systematic screening with sonography to detect prenatally CL ± P requires the imaging of at least the mid‐sagittal and the anterior coronal ‘nose‐mouth’ views. Once the presence of a facial cleft is suspected, the three reference orthogonal planes are imaged in order to characterize the anatomical defect, and for each plane, the serial scans are thoroughly examined. This protocol allows precise delineation of the defect. Inclusion of 3D and 4D ultrasound imaging in the examination protocol allows easier and more rapid screening and more precise evaluation of the different cleft constituents. Copyright © 2004 ISUOG. Published by John Wiley & Sons, Ltd.
Effect of radiation therapy on trace elemental concentrations of hair samples of cervical cancer patients—PIXE technique
Authors: Charles M. John , Reddy S. Bhuloka , Raju G. J. Naga , Ravi Kumar M. , Seetharamireddy B. , Mallikharjuna Rao B. , Reddy T. Seshi , Murty G. A. V. Ramana , Ramakrishna Y. , Vijayan V. , Ramani A.
Published: August 2004

Trace elemental analysis of hair samples from subjects suffering with cervical cancer before radiation therapy and at successive intervals during radiation therapy was carried out using the PIXE technique. A 2 MeV proton beam was employed. The elements Cl, K, Ca, Ti, Cr, Mn, Fe, Ni, Cu, Zn and Pb were identified and their relative concentrations were estimated. The concentrations of Cl, K, Ca, Ti, Cr, Mn, Fe, Ni and Zn were found to be lower in hair samples of cervical cancer patients before radiation therapy than those from controls, whereas the concentration of Cu showed the opposite trend. The concentrations of Cl, K, Ca, Ti, Mn, Fe, Cu, Zn and Pb showed a definite trend of variation with successive intervals of radiation therapy, which indicates that these elements are affected during radiation therapy. The Cu/Zn ratio also decreases with successive radiation therapy. Copyright © 2004 John Wiley & Sons, Ltd.
Characterization of chromium‐containing ceramic pigments by XRF and XRD
Authors: Gazulla M. F. , Gómez M. P. , Barba A. , Mestre S.
Published: August 2004

As no methodology was found in the literature for characterizing ceramic pigments chemically and mineralogically, the present study was undertaken to establish a methodology for the chemical and phase characterization of ceramic pigments by x‐ray fluorescence (XRF) spectrometry and x‐ray diffraction (XRD). In view of the large number of pigments described in the literature (around 44), the present study was limited to characterizing pigments that contained chromium, which is the most versatile chromophore used in ceramics. Copyright © 2004 John Wiley & Sons, Ltd.
A simple x‐ray monochromator based on an alligator lens
Authors: Jark W.
Published: August 2004

Alligator lenses, i.e. two inclined arrays of sawteeth or prisms, which face each other, can focus x‐rays with photon energies >4 keV. The inclination angle can be changed easily, and thus either the focal length for fixed photon energy or the photon energy in a fixed slit position can be varied. The material distribution in this condition is approximately parabolic along the teeth axis, hence it is of the shape required for aberration‐free focusing at a given photon energy. As the refractive index varies significantly with photon energy in the x‐ray range, these lenses suffer from chromatic aberrations, if illuminated with white x‐rays. In combination with a slit such a lens can therefore be used as an easily insertable inline monochromator. In this work, a simple universal function for the dependence of the transmission on the photon energy was derived for this application. The required tolerances for the shape of the sawteeth are found to be compatible with standard workshop machining procedures. A laboratory‐made lens of Plexiglas is shown to increase the flux density in a laboratory setup by a factor of 3, i.e. 50% of the expected result for a perfect lens. The discrepancy can be consistently ascribed to macroscopic defects of the sawteeth tips. Expectations for the performance of these lenses as monochromators at synchrotron radiation sources are presented. A single Be alligator lens is expected to provide tuning between at least 8 keV and 20 keV photon energy with a bandpass of 6%, sufficient for XRF and SAXS experiments. Consequently, such a lens pair is all that is needed for building simple synchrotron radiation beamlines for special x‐ray experiments. Copyright © 2004 John Wiley & Sons, Ltd.
Analysis of the effects of geometry on the fluorescence radiation field in the frame of transport theory
Authors: Fernández J. E. , Molinari V. G. , Teodori F.
Published: August 2004

In x‐ray fluorescence spectroscopy, a photon beam is focused on the sample to stimulate the emission of characteristic radiation. Even if a qualitative interpretation of the measurements is simple, a quantitative analysis is not straightforward because the primary photons are produced deep in the target and the properties of the radiation that reaches the detector are modified significantly by the interactions undergone before leaving the specimen. Understanding how the emission spectra are influenced by interactions with matter is a central problem in fluorescence analysis. In this work, by using the 3D transport equation, we found that not only the composition of the specimen but also the geometry of the system plays an important role in determining the properties of the radiation field, denoting by geometry the shape of the target, the direction of the incoming beam and the observation angle. Copyright © 2004 John Wiley & Sons, Ltd.
XANES studies of monosubstituted benzhydrazide complexes of copper
Authors: Joshi S.K. , Shrivastava B.D. , Shrivastava Bhakta Darshan , Mishra A.
Published: August 2004

K x‐ray absorption near‐edge structure (XANES) studies were carried out on nine samples of monosubstituted benzhydrazide complexes of copper, viz. copper(II) benzhydrazide, o‐, m‐ and p‐hydroxybenzhydrazide, o‐, m‐ and p‐nitrobenzhydrazide and o‐ and p‐chlorobenzhydrazide. These complexes are known for their pharmacological activity as antitubercular agents, antibacterial agents and as fungicides. In the three categories of substituted benzhydrazides the ionicity is found to increase in the order para > meta > ortho. Our studies revealed that the substituted complexes are less ionic than the parent complex. Among the three groups, hydroxy‐substituted complexes are more ionic than nitro‐ and chloro‐substituted hydrazides. Splitting of the principal absorption maximum (1s → 4p) takes place in most of these complexes. The splitting into two components has been assigned to the transitions 1s → A*(4pz) and 1s → B*(4px, 4py). The estimated bandgap values for these complexes decrease in the order ortho > meta > para. The present studies indicate that as the chemical shift values increase in all the three groups, the bandgap energy values decrease. Copyright © 2004 John Wiley & Sons, Ltd.
Cloning and functional characterization of a rat Daxx that functions as a corepressor for the androgen receptor
Authors: Mizuta Haruo , Kuroda Yasuo
Published: August 2004

The androgen receptor (AR), a ligand‐activated nuclear transcription factor, plays an important role in endocrine system development and homeostasis. AR‐mediated gene transcription is modulated by a wide variety of coregulator proteins, but corepressors of AR have not been well characterized. We have isolated a rat homologue of Daxx, a possible AR repressor. The clone obtained comprised a 2196 bp open reading frame, corresponding to a sequence of 731 amino acids with 80.5% homology to mouse. Basal transcription of the isolated clone was repressed in transient transcription experiments using a Gal4 reporter gene assay. Furthermore, a mammalian two‐hybrid assay showed a strong interaction between Daxx and promyelocytic leukemia (PML) protein. These results indicate that the isolated clone is a rat homologue of Daxx. The rat Daxx (rDaxx) interacted with the androgen receptor (AR): in co‐immunoprecipitation experiments, AR formed complexes with anti‐Daxx antibody. Furthermore, overexpression of Daxx suppressed AR‐mediated transcriptional activity in HeLa and CV1 cells in transient transfection experiments. Taken together, our results suggest that Daxx may function as a corepressor for the androgen receptor.
The trimeric organisation of photosystem I is not necessary for the iron‐stress induced CP43′ protein to functionally associate with this reaction centre
Authors: Aspinwall Caroline L. , Duncan James , Bibby Thomas , Mullineaux Conrad W. , Barber James
Published: August 2004

A mutant of Synechocystis PCC 6803 lacking the PsaL subunit of photosystem I (PSI) has been grown in iron‐deficient media to induce the expression of the isiA gene, which encodes the chlorophyll a‐binding protein CP43′. The purpose of this was to establish whether or not the formation of an 18‐mer CP43′‐PSI supercomplex reported for wild type Synechocystis cells [Nature 412 (2001) 743–745] was dependent on the trimeric conformation of the cyanobacterial PSI reaction centre. Structural characterisation by electron microscopy and single particle image analysis has revealed that the PsaL‐mutant does not form trimers of PSI. However, despite this, CP43′ was found to associate with the PSI monomer. The PSI monomer bound six or seven copies of CP43′ along one edge of the PSI monomer and can be compared with one segment of the trimeric 18‐mer CP43′‐PSI supercomplex. We therefore conclude that the trimeric nature of cyanobacterial PSI is not required for the assembly of the CP43′ antenna system under iron‐deficient conditions.
Characterization of trans‐ and cis‐cleavage activity of the SARS coronavirus 3CLpro protease: basis for the in vitro screening of anti‐SARS drugs
Authors: Lin Cheng-Wen , Tsai Chang-Hai , Tsai Fuu-Jen , Chen Pei-Jer , Lai Chien-Chen , Wan Lei , Chiu Hua-Hao , Lin Kuan-Hsun
Published: August 2004

Severe acute respiratory syndrome (SARS) has been globally reported. A novel coronavirus (CoV), SARS‐CoV, was identified as the etiological agent of the disease. SARS‐CoV 3C‐like protease (3CLpro) mediates the proteolytic processing of replicase polypeptides 1a and 1ab into functional proteins, playing an important role in viral replication. In this study, we demonstrated the expression of the SARS‐CoV 3CLpro in Escherichia coli and Vero cells, and then characterized the in vitro trans‐cleavage and the cell‐based cis‐cleavage by the 3CLpro. Mutational analysis of the 3CLpro demonstrated the importance of His41, Cys145, and Glu166 in the substrate‐binding subsite S1 for keeping the proteolytic activity. In addition, alanine substitution of the cleavage substrates indicated that Gln‐P1 in the substrates mainly determined the cleavage efficiency. Therefore, this study not only established the quantifiable and reliable assay for the in vitro and cell‐based measurement of the 3CLpro activity, but also characterized the molecular interaction of the SARS‐CoV 3CLpro with the substrates. The results will be useful for the rational development of the anti‐SARS drugs.
Truncated KCNQ1 mutant, A178fs/105, forms hetero‐multimer channel with wild‐type causing a dominant‐negative suppression due to trafficking defect
Authors: Aizawa Yoshiyasu , Ueda Kazuo , Wu Long-mei , Inagaki Natsuko , Hayashi Takeharu , Takahashi Megumi , Ohta Masaaki , Kawano Seiko , Hirano Yuji , Yasunami Michio , Aizawa Yoshifusa , Kimura Akinori , Hiraoka Masayasu
Published: August 2004

We identified a novel mutation Ala178fs/105 missing S3–S6 and C‐terminus portions of KCNQ1 channel. Ala178fs/105‐KCNQ1 expressed in COS‐7 cells demonstrated no current expression. Co‐expression with wild‐type (WT) revealed a dominant‐negative effect, which suggests the formation of hetero‐multimer by mutant and WT. Confocal laser microscopy displayed intracellular retention of Ala178fs/105‐KCNQ1 protein. Co‐expression of the mutant and WT also increased intracellular retention of channel protein compared to WT alone. Our findings suggest a novel mechanism for LQT1 that the truncated S1–S2 KCNQ1 mutant forms hetero‐multimer and cause a dominant‐negative effect due to trafficking defect.
Comparative analysis of phosphoprotein‐enriched myocyte proteomes reveals widespread alterations during differentiation
Authors: Puente Lawrence G. , Carrière Jean-François , Kelly John F. , Megeney Lynn A.
Published: August 2004

The differentiation of skeletal muscle has been associated with altered phosphorylation status of individual proteins. However, a global analysis of protein phosphorylation during myogenesis has yet to be undertaken. Here, we report the identification of over 130 putative phosphoproteins from murine C2C12 muscle cells. Cell extracts were fractionated on phosphoprotein enrichment columns and the resulting proteins were detected by two‐dimensional gel electrophoresis and silver stain, and identified by liquid chromatography coupled to electrospray tandem mass spectrometry. The early differentiation of C2C12 myoblasts was found to be accompanied by changes in the phosphorylation or expression of numerous proteins including cytoskeletal, heat shock and signaling proteins, the pp32 family of nuclear phosphoproteins, several disease‐associated gene products and other characterized and uncharacterized proteins.
Mutational analysis of conserved AAA+ residues in the archaeal Lon protease from Thermoplasma acidophilum
Authors: Besche Henrike , Tamura Noriko , Tamura Tomohiro , Zwickl Peter
Published: August 2004

The Lon protease from the archaeon Thermoplasma acidophilum (TaLon) is composed of an N‐terminal ATPase associated with various cellular activities (AAA+) domain and a C‐terminal Lon protease domain. Although related in sequence to the soluble Lon proteases, TaLon was shown to be membrane‐bound in its native host and also when expressed in Escherichia coli. Recombinant TaLon was purified as a functional high‐molecular weight complex displaying ATPase and proteolytic activity. Mutagenesis of conserved AAA+ residues revealed that the Walker A and B motifs, and the sensor 1 and sensor 2′ residues were essential for the ATPase activity, while the sensor 2 and the arginine finger were involved in activation of the protease domain.
Exon 6 of human Jagged‐1 encodes an autonomously folding unit
Authors: Guarnaccia Corrado , Pintar Alessandro , Pongor Sándor
Published: August 2004

Human Jagged‐1 is predicted to contain 16 epidermal growth factor‐like (EGF) repeats. The oxidative folding of EGF‐2, despite the several conditions tested, systematically led to complex mixtures. A longer peptide spanning the C‐terminal part of EGF‐1 and the complete EGF‐2 repeat, on the contrary, could be readily refolded. This peptide, which corresponds to the entire exon 6 of the Jagged‐1 gene, thus represents an autonomously folding unit. We show that it is structured in solution, as suggested by circular dichroism and NMR spectroscopy, and displays an EGF‐like disulfide bond topology, as determined by disulfide mapping.
Evolutionary analysis of 11β‐hydroxysteroid dehydrogenase‐type 1, ‐type 2, ‐type 3 and 17β‐hydroxysteroid dehydrogenase‐type 2 in fish
Authors: Baker Michael E.
Published: August 2004

Steroid dehydrogenases regulate the access of active steroids to their receptors. In particular, 11β‐hydroxysteroid dehydrogenase‐type 1 (11β‐HSD1) and 11β‐HSD2 regulate the levels of glucocorticoids, such as cortisol, and 17β‐HSD1 and 17β‐HSD2 regulate the levels of androgens and estrogens. Human 11β‐HSD1 and 11β‐HSD2 are distant homologs, with less than 25% amino acid sequence identity, as are human 17β‐HSD1 and 17β‐HSD2. In contrast, human 11β‐HSD2 and 17β‐HSD2 are close homologs, with about 43% sequence identity. Until recently, deciphering early events in the evolution of 11β‐HSD2 and 17β‐HSD2 was difficult because only mammalian sequences were available. The completely sequenced Takifugu, Tetraodon and medaka genomes and the almost completed zebrafish genome provide an opportunity to investigate the evolution of 11β‐HSD2, 17β‐HSD2, and 11β‐HSD1. Unexpectedly, a search of the Takifugu, Tetraodon and medaka genomes only found an ortholog to 11β‐HSD2 and none to 17β‐HSD2, while the zebrafish genome contains orthologs of both enzymes. This suggests that 17β‐HSD2 was lost in teleosts after the divergence of zebrafish and medaka. Also unexpectedly, searches with 11β‐HSD1 only identified several fish 11β‐HSD3s, as well as an ortholog in Ciona, indicating that 11β‐HSD3 is the ancestor of 11β‐HSD1.
Atypical protein kinase C stimulates nucleotide excision repair activity
Authors: Louat Thierry , Canitrot Yvan , Jousseaume Sandra , Baudouin Caroline , Canal Pierre , Laurent Guy , Lautier Dominique
Published: August 2004

Nucleotide excision repair (NER) deals with bulky DNA damages. However, the regulation of this process is still unclear. Here, we show that both cell resistance to genotoxic agents that generate DNA lesions corrected by NER and in vitro NER activity are correlated with atypical protein kinase C (PKC) ζ expression levels. Moreover, repair intermediates are produced and eliminated more rapidly in UV‐irradiated PKCζ‐overexpressing cells. The expression levels of XPC and hHR23B, two NER proteins, are correlated with PKCζ expression. Altogether, these results strongly suggest that PKCζ could act as a modulator of NER activity by regulating the expression of XPC/hHR23B heterodimer.
Laboratory evidence for behavioural impairment of fish escaping trawls: a review
Authors: Ryer Clifford H.
Published: August 2004

It is now widely accepted that for some species a proportion of the undersized fish escaping trawl codends die as a direct result of stress, with 10% to 30% mortality commonly cited. It has also been suggested that there may be indirect or behaviourally mediated mortality; fish that encounter and escape the trawl, only to experience stress-induced behavioural deficits and succumb to predators in the hours or days afterwards. The goal of this review was to evaluate the plausibility of this behaviourally mediated, yet unobserved mortality. Three laboratory studies utilizing cod (Gadus morhua), walleye pollock (Theragra chalcogramma), and sablefish (Anoplopoma fimbria) have assayed for behavioural impairment in fish following application of stressors designed to simulate entrainment and escape from trawls. Where impairments in anti-predator capabilities occurred, it was determined that trawl-stressed fish exhibited reduced swimming speed, reduced shoal cohesion, and reduced predator vigilance compared to control fish. Although stressed fish appeared to rapidly recover their ability to avoid being eaten by predators, measurements of more subtle aspects of escapee behaviour suggest that impairments may persist for days after stressor application. Although these studies demonstrate that more investigation is required, when combined with a more extensive literature demonstrating that a variety of stressors can impair fish anti-predator behaviour, it is reasonable to conclude that many fish species escaping trawl codends will likely suffer behavioural deficits that subject them to elevated predation risk. As such, there is probably mortality associated with trawl fisheries that is generally unrecognized, unmeasured, and unaccounted for in current stock assessment models. Further, these studies demonstrate that behavioural competency needs to be considered in the design and implementation of by-catch reduction devises and strategies.
Review of technological advances for the study of fish behaviour in relation to demersal fishing trawls
Authors: Graham N. , Jones E.G. , Reid D.G.
Published: August 2004

In demersal trawling, there is a need to develop more species-selective trawls to minimize discarding in multispecies fisheries. This requires observational tools that can operate at depths and light levels encountered by the commercial fleets. There is a growing tendency towards more fishery-independent stock-assessment methods using survey trawls to provide population indices. This requires the ability to quantify the herding and capture efficiency by species and age groups of such gears. A range of optical and acoustic observation techniques has been developed over the past few decades to assist in these goals. In this paper we update the review of technologies presented at the ICES Symposium on Fish Behaviour in Relation to Fishing Operations held in 1992. Since then, considerable advances in optical, acoustic, and data-processing technology have been made.
Autism associated with conditions characterized by developmental errors in early embryogenesis: a mini review
Authors: Miller Marilyn T. , Strömland Kerstin , Ventura Liana , Johansson Maria , Bandim Jose M. , Gillberg Christopher
Published: August 2004

Autism is a complex developmental disorder without an established single etiology but with significant contributions from genetic studies, functional research, and neuropsychiatric and neuroradiologic investigations. The purpose of this paper is to review the findings in five studies involving individuals manifesting the characteristic findings of autism spectrum disorder associated with malformations and dysfunctions known to result from early embryogenic defects. These investigations include two associated with teratogens (thalidomide embryopathy, Möbius sequence with misoprostol) and three (most Möbius sequence cases, CHARGE association, Goldenhar syndrome) with no known etiology.

These studies suggest that early embryonic development errors often involving cranial nerve palsies, internal and external ear malformations, ophthalmologic anomalies, and a variety of systemic malformations may be associated with autism spectrum disorders statistically more frequently than expected in a normal population. Although the exact time of developmental insult for each condition cannot be identified, the evidence is that it may occur as early as week 4 to 6+ of embryogenesis.
Tau‐inclusion body formation in oligodendroglia: the role of stress proteins and proteasome inhibition
Authors: Richter‐Landsberg Christiane , Bauer Nina G.
Published: August 2004

Filamentous tau‐positive inclusions in neurons and glia are a unifying mechanism underlying a variety of late onset neurodegenerative disorders termed “tauopathies”. Oligodendroglial lesions and white matter pathology have long been underestimated and are specifically prominent in frontotemporal dementias (FTDs), such as Pick's disease (PiD), progressive supranuclear palsy (PSP), corticobasal degeneration (CBD) and frontotemporal dementia with Parkinsonism linked to chromosome 17 (FTDP‐17). Oligodendrocytes contain an extensive microtubule network and express the microtubule‐associated protein tau. Tau‐positive inclusion bodies in oligodendrocytes are postively stained with antibodies against ubiquitin and heat shock proteins (HSPs). Specifically the small HSP αB‐crystallin has been identified in oligodendroglial lesions. HSPs act as molecular chaperones and prevent the accumulation of abnormal proteins, and support proteolytic degradation by targeting non‐reparable proteins to the ubiquitin proteasomal pathway. HSPs and the proteasomal system closely work together. The present report summarizes recent data on HSP induction and aggregate formation in oligodendroglia cell culture systems, indicating that posttranslational modification of tau, HSP induction and alterations of the proteasomal system, which might occur during aging and disease processes, are involved in the neuropathological events leading to aggregate formation and degeneration.
New players in old amyloid precursor protein‐processing pathways
Authors: Roßner Steffen
Published: August 2004

The amyloid precursor protein (APP) gives rise to β‐amyloid peptides, which are the main constituents of senile plaques in brains of Alzheimer's disease (AD) patients. The generation of β‐amyloid peptides requires the enzymatic activity of the β‐site APP‐cleaving enzyme 1 (BACE1). BACE1 is primarily expressed by neurons and increased BACE1 protein concentrations and enzymatic activities have been reported in the brains of AD patients. However, there is accumulating evidence that, in addition to neurons, reactive astrocytes are capable of expressing BACE1 and, therefore, may contribute to β‐amyloid plaque formation. This suggests that conditions accompanied by chronic astrocyte activation may contribute to developing AD.

Non‐amyloidogenic processing of the APP can be stimulated by phorbol esters (PEs) and by intracellular diacylglycerol (DAG) generation. This led to the hypothesis that classical and novel protein kinase Cs (PKCs), which are activated by DAG/PEs, regulate APP processing. However, in addition to PKCs, there are other DAG/PE receptors present in neurons which may participate in the modulation of APP processing. Munc13‐1, a presynaptic protein with an essential role in synaptic vesicle priming, represents such an alternative target of the DAG second messenger pathway. Using Munc13‐1 knock‐out mice and human neuroblastoma cells transfected with wild‐type and mutant Munc13‐1 constructs it was demonstrated that Munc13‐1 acts independently of and in parallel with PKC to modulate APP metabolism. Therefore, agonists specific for the Munc13‐1 C1‐domain or small molecules mimicking the function of the endogenous Munc13‐1 activator RIM1 may prove useful to shift APP processing towards the non‐amyloidogenic pathway.
Malignant transformation of endometriosis and genetic alterations of K‐ras and microsatellite instability
Authors: Amemiya S. , Sekizawa A. , Otsuka J. , Tachikawa T. , Saito H. , Okai T.
Published: August 2004

Objectives: To clarify the role of specific genetic alterations in the multi‐step process of malignant transformation of endometriosis. Methods: In cases of ovarian endometrioid carcinoma, we separated regions of normal endometriosis, atypical endometriosis and ovarian endometrioid carcinoma by laser microdissection, and examined K‐ras mutation and microsatellite instability in each separated tissue sample. Results: We detected K‐ras mutation and microsatellite instability in endometrioid carcinoma tissue, but not in normal or atypical endometriosis bordering the cancerous region. Conclusions: The present findings suggest that K‐ras mutation and microsatellite instability are associated with malignant transformation from atypical endometriosis to ovarian endometrioid carcinoma.
Study of Lubricant‐Induced Changes in Chronic Snorers
Authors: Wijewickrama Rohan C , Blalock P David , Mims James W
Published: August 2004

Problem

The efficacy of many of the noninvasive treatments for snoring has not been evaluated in controlled trials. This study seeks to evaluate the efficacy of an oil‐based spray in the treatment of snoring, in a double‐blinded, placebo‐controlled, cross‐over trial using objective acoustic analysis and subjective questionnaires.

Methods

Participants were randomized to use both oilbased oral spray (treatment) and water‐based oral spray (placebo) during a 2‐night in‐home study period. Questionnaires were completed by the participant and his/her bed‐partner; these were evaluated along with audiotape recordings, which were analyzed for frequency, duration, and mean energy of snoring.

Results

Greatest snoring rate demonstrated 30% = benefit; 40% = no change; 30% = adverse effect (n = 20). percent time snoring yielded: 30% = benefit; 15% = no change; 55% = adverse effect (n = 20). Study data results for mean energy were (n = 12): 17% = benefit; 33% = no change; 50% = adverse effect. Bed‐partner observations (n = 17) demonstrated 37% = benefit; 38% = no change, 25% = adverse effect.

Conclusion

Objective and subjective evaluation of the performance of the oil‐based Snoreless spray in comparison to placebo demonstrated a lack of efficacy in snoring reduction.

Significance

Study findings indicate that oil‐based oral sprays are not effective in the treatment of snoring.

Support

None reported.
Acceptance of Treatment Suggestions for Sleep‐Disordered Breathing
Authors: Verse Thomas , Wiesmiller Kerstin , Pirsig Wolfgang , Stuck Boris A , Maurer Joachim T , Hoermann Karl
Published: August 2004

Problem

Sleep‐disordered breathing is one of the most widespread diseases in industrialized countries. Unfortunately, even in severe cases, sleep apnea patients often do not follow the treatments suggested. The aim of this study was to investigate (1) the primary acceptance rates in relation to the kind of treatment suggested and (2) whether there are characteristic differences between patients who accept and those who do not accept the treatments recommended.

Methods

In our study, 503 patients with sleep‐disordered breathing underwent complete fully attended polysomnography in the sleep lab. With regard to the nature and severity of their sleep disorder and the individual clinical findings, 171 patients were recommended to undergo nCPAP, 42 to use a mandibular advancement device (MAD), and for 244 patients a surgical treatment was suggested. In 21 cases there was no need for any kind of treatment, and in the other 25 cases only weight loss was suggested.

Results

In total, 234 patients accepted the treatment suggested (46.5%). In detail, the recommendations were accepted as follows: nCPAP 54%, surgery 42%, MAD 40.5%, and weight loss 4%. Gender did not have any affect on the acceptance rate. The youngest and the oldest patients showed higher acceptance rates (<24 years 100%, >65 years 62%). In general patients with more severe disease tended to accept treatment more frequently (acceptance rate of 40% for primary snorers vs 85% for patients with severe sleep apnea; P < 0.05).

Conclusion

The acceptance rate of treatment suggestions for sleep‐disordered breathing is dependent on the severity of the disease. This may be due to the more pronounced clinical symptoms going along with increasing severity of the disease. The kind of treatment suggested (apart from weight loss) and the age of the patients seem to have only minor influence on the primary acceptance of treatment suggestions, while gender seems to have no effect at all.

Significance

In mild sleep apnea, the consequences of the disease have to be accounted very carefully to the patient in order to achieve the patient's compliance for any kind of treatment.

Support

No comments.
Patient Selection and Efficacy of the Pillar Implant Technique for Snoring and OSAHS
Authors: Friedman Michael , Vidyasagar Ramakrishnan , Bliznikas Darius
Published: August 2004

Problem

Stiffening the soft palate using a palatal implant is an innovative technique, introduced for clinical practice in 2003. This is a simple, office‐based procedure with minimal morbidity. Our objective was to identify (1) the success rate using subjective symptoms and objective improvement of OSAHS; (2) the success rate based on Friedman's clinical stage to develop patient selection criteria; and (3) the technique's value as an adjunctive or revision procedure.

Methods

The study was a retrospective chart review of the first 100 patients undergoing the Pillar implant. Data collected included: previous treatments for snoring and/or OSAHS, adjunctive procedures, preoperative and two‐month postoperative snore level, Epworth sleepiness scale (ESS), PSG, and complications. Charts were grouped as follows: group I had no adjunctive and previous treatments; group II received adjunctive nasal and/or tongue base procedures; and group III had previous UP3.

Results

Patients with primary snoring and mild and moderate OSAHS were treated. The AHI level was not a predictor of success. Group I patients (n = 36) had significant improvement in snoring levels, but not in ESS or AHI. Twenty‐six patients (72.2%) were considered successful based on elimination of symptoms. Group II patients (n = 43) had the best results. Mean AHI and ESS improved and snore level decreased. Thirty‐five patients (81%) were rated as successful. Group III (n = 21) patients had no change in AHI or ESS but showed significantly decreased snoring. Twelve patients (57%) were rated as successful. Complications were limited to 4 patients with partial extrusion.

Conclusion

The Pillar implant is an easy and effective office‐based procedure to treat snoring and OSAHS in selected patients.

Significance

This study demonstrates the efficacy of the palatal implant technique alone and in combination with adjunctive procedures in decreasing snoring levels and treating OSAHS.

Support

None reported.