bluuebunny/crossref_metadata_2025 huggingface dataset:
Carcinoma secretor da mama no adulto: existem parâmetros bem definidos para decisão terapêutica?
Authors: Gouveia António Manuel Ferreira , Lopes José Manuel , Pimenta Amadeu P. Araújo
Published: April 2005

O carcinoma secretor (CS) da mama é uma neoplasia muito rara. O CS da mama foi inicialmente descrito em crianças e adolescentes, mas a maioria dos casos é descrito em doentes adultos. É muitas vezes associado a um prognóstico particularmente favorável, mas em doentes adultos com tumores de maiores dimensões pode apresentar um comportamento mais agressivo. Apresenta-se um caso de uma doente com 62 anos de idade, que apresentava uma volumosa tumefacção da mama com 16 anos de evolução. O exame objetivo revelou extensa fixação da lesão à pele, com sinais inflamatórios acentuados e áreas de necrose cutânea. O tratamento inicial consistiu numa mastectomia simples, com intenção paliativa. O diagnóstico anatomopatológico de carcinoma secretor (3,5 cm), sem invasão cutânea, motivou a posterior realização de esvaziamento ganglionar axilar, que revelou metástases em 2 dos 13 gânglios isolados. A doente faleceu 24 meses depois, por disseminação da doença, comprovando a maior agressividade do CS em doentes adultos com tumores de maiores dimensões (T2) e com metastização ganglionar (N1). Os autores revêem a literatura com particular ênfase nos factores de prognóstico importantes para decisão terapêutica deste tipo raro de carcinoma da mama, em doentes adultos.
Treinamento em microanastomoses utilizando tubos de látex
Authors: Pessoa Breno Bezerra Gomes de Pinho , Pessoa Salustiano Gomes de Pinho
Published: April 2005

Introdução: Treinamento em materiais inertes é um pré-requisito para o emprego experimental e clínico da técnica microcirúrgica. Apresenta-se uma nova abordagem para treinamento em microanastomoses vasculares que consiste na confecção de tubos a partir de luvas de látex. Métodos: Utilizando-se retângulos de látex obtidos de uma luva cirúrgica confeccionou-se tubos de diâmetros variados (menor diâmetro de 0,5mm) onde se realizou microanastomoses término-terminais e término-laterais utilizando fios de Nylon números 9, 10 e 11-0. Conclusão: Acredita-se que o modelo acrescenta as formas tradicionais de treinamento em microcirurgia no sentido de minimizar custos e poupar animais de experimentação.
Effect of Ultrafiltration on Thermal Variables, Skin Temperature, Skin Blood Flow, and Energy Expenditure during Ultrapure Hemodialysis
Authors: van der Sande Frank M. , Rosales Laura M. , Brener Zohar , Kooman Jeroen P. , Kuhlmann Martin , Handelman Garry , Greenwood Roger N. , Carter Mary , Schneditz Daniel , Leunissen Karel M. , Levin Nathan W.
Published: April 2005

The cause of the increase in core temperature (CT) during hemodialysis (HD) is still under debate. It has been suggested that peripheral vasoconstriction as a result of hypovolemia, leading to a reduced dissipation of heat from the skin, is the main cause of this increase in CT. If so, then it would be expected that extracorporeal heat flow (Jex) needed to maintain a stable CT (isothermic; T-control = 0, no change in CT) is largely different between body temperature control HD combined with ultrafiltration (UF) and body temperature control HD without UF (isovolemic). Consequently, significant differences in ΔCT would be expected between isovolemic HD and HD combined with UF at zero Jex (thermoneutral; E-control = 0, no supply or removal of thermal energy to and from the extracorporeal circulation). During the latter treatment, the CT is expected to increase. In this study, changes in thermal variables (CT and Jex), skin blood flow, energy expenditure, and cytokines (TNF-α, IL-1 receptor antagonist, and IL-6) were compared in 13 patients, each undergoing body temperature control (T-control = 0) HD without and with UF and energy-neutral (E-control = 0) HD without and with UF. CT increased equally during energy-neutral treatments, with (0.32 ± 0.16°C;

P

= 0.000) and without (0.27 ± 0.29°C;

P

= 0.006) UF. In body temperature control treatments, the relationship between Jex and UF tended to be significant (

r

= −0.51;

P

= 0.07); however, there was no significant difference in cooling requirements regardless of whether treatments were done without (−17.9 ± 9.3W) or with UF (−17.8 ± 13.27W). Changes in energy expenditure did not differ among the four treatment modes. There were no significant differences in pre- and postdialysis levels of cytokines within or between treatments. Although fluid removal has an effect on thermal variables, no single mechanism seems to be responsible for the increased heat accumulation during HD.
Substance Use and Vulnerability to Sexual and Physical Aggression: A Longitudinal Study of Young Adults
Authors: Martino Steven C. , Collins Rebecca L. , Ellickson Phyllis L.
Published: April 2005

Using data from 2,170 individuals who participated in Waves 8 (age 23) and 9 (age 29) of a multiyear panel study, this study examined whether alcohol and marijuana use in young adulthood increase one’s risk for experiencing subsequent sexual or physical assault victimization, whether victims’ own violent behavior or involvement in the sale of drugs explain any effects of substance use on victimization, and whether these associations differ by gender. Controlling for prior victimization, we found that marijuana use, but not alcohol use, predicted women’s and men’s subsequent sexual victimization and men’s subsequent physical assault victimization, and that heavy alcohol use, but not marijuana use, predicted women’s subsequent physical assault victimization. Whereas the links from marijuana use to victimization were explained by users’ own violent behavior, the link from alcohol use to women’s physical assault victimization was not.
Men’s Sexual Coercion in Intimate Relationships: Development and Initial Validation of the Sexual Coercion in Intimate Relationships Scale
Authors: Shackelford Todd K. , Goetz Aaron T.
Published: April 2005

We report the development and initial validation of the Sexual Coercion in Intimate Relationships Scale (SCIRS), a measure designed to assess the prevalence and severity of sexual coercion in committed intimate relationships. We review existing measures of sexual coercion and discuss their limitations, describe the identification of the SCIRS items, perform a principal components analysis and describe the resulting three components, and present evidence for the convergent and discriminative validity of the SCIRS. Because sexual coercion in intimate relationships often takes the form of subtle tactics, the SCIRS items assess communicative tactics such as hinting and subtle manipulations in addition to tactics such as the use of physical force. The SCIRS provides researchers and clinicians with a valid, reliable, and comprehensive measure with which to study the dynamics of sexual coercion in intimate relationships.
Optimization of inlet temperature for deactivating LTWGS reactor performance
Authors: Ayastuy J. L. , Gutiérrez‐Ortiz M. A. , González‐Marcos J. A. , Aranzabal A. , González‐Velasco J. R.
Published: April 2005

An industrial Cu‐based low‐temperature water‐gas shift (LTWGS) reactor, subject to deactivation by irreversible chlorine adsorption, has been modeled and optimized. Both the chlorine adsorption kinetics and deactivation kinetics were assumed first order to chlorine partial pressure, and the rate constants were considered independent of temperature. The Efficient Production (EP) method has been used to compute the reactor production until the outlet CO conversion decays below a permissible minimum level. Two alternative strategies for the inlet temperature have been used to maximize the EP: constant and time‐variable. Compared to the EP obtained for the optimum constant inlet temperatures, EP resulting from the use of the optimum time‐variable inlet temperature sequence were higher, affording important energy savings. Furthermore, a sensitivity study with respect to most influential operational variables, such as inlet total flow rate, steam‐to‐gas ratio, pressure, and concentrations of chlorine, hydrogen, carbon monoxide, and inert content, was carried out. © 2005 American Institute of Chemical Engineers AIChE J, 2005
Geometric morphometric analysis of mandibular ramus flexure
Authors: Oettlé A.C. , Pretorius E. , Steyn M.
Published: April 2005

Many characteristics of the human skeleton can only be assessed morphologically, which may be problematic due to factors such as interobserver error and difficulties with standardization. Flexure of the mandibular ramus is one of these traits, and various researchers found widely differing results using this morphological feature. The aim of this study was to determine whether differences between male and female mandibular rami could be observed using the computerized method of geometric morphometrics, a valuable tool that helps quantify shape differences. Twenty‐eight mandibular rami of black females and 43 of black males were photographed in a standard plane and assessed. It was found that the females were more scattered on the graph (more variable in shape), while the males clustered more around the center point where the two axes met (shape more constant). There was, however, considerable overlap between the sexes. Although different tendencies exist between the rami of males (being more flexed) and females (tending to be straight), the extent of these differences is not adequate to predict the sex of a single individual. Am J Phys Anthropol, 2005. © 2005 Wiley‐Liss, Inc.
Linear enamel hypoplasias as indicators of systemic physiological stress: Evidence from two known age‐at‐death and sex populations from postmedieval London
Authors: King T. , Humphrey L.T. , Hillson S.
Published: April 2005

Enamel hypoplasias are useful indicators of systemic growth disturbances during childhood, and are routinely used to investigate patterns of morbidity and mortality in past populations. This study examined the pattern of linear enamel hypoplasias in two different burial populations from 18th and 19th Century church crypts in London. Linear enamel hypoplasias on the permanent dentitions of individuals from the crypt of Christ Church, Spitalfields, were compared to enamel defects on the teeth of individuals from St. Bride's. The method used involves the identification of enamel defects at a microscopic level, and systemic perturbations are detected by matching hypoplasias among different tooth classes within each individual. The pattern of linear enamel hypoplasias was contrasted between individuals from the burial sites of Spitalfields and St. Bride's, between males and females, and between those aged less than 20 years of age and those aged over 20 years at death. Six different parameters were examined: frequency of linear enamel hypoplasias, interval between defects, duration of hypoplasias, age at first occurrence of hypoplasia, age at last occurrence of hypoplasia, and the percentage of enamel formation time taken up by growth disturbances. All individuals in the study displayed linear enamel hypoplasias, with up to 33% of total visible enamel formation time affected by growth disruptions. Multiple regression analysis indicated a number of significant differences in the pattern of enamel hypoplasias. Individuals from Spitalfields had shorter intervals between defects and greater percentages of enamel formation time affected by growth disturbances than did individuals from St. Bride's. Females had greater numbers of linear enamel hypoplasias, shorter intervals between defects, and greater percentages of enamel formation time affected by growth disturbances than males. There were also differences in the pattern of enamel hypoplasias and age at death in this study. Individuals who died younger in life had an earlier age at first occurrence of enamel hypoplasia than those who survived to an older age. The pattern of enamel hypoplasias detected in this study was influenced by tooth crown geometry and tooth wear such that most defects were found in the midcrown and cervical regions of the teeth, and greater numbers of defects were identified on the anterior teeth. Differences in sensitivity of the parameters used for the detection of enamel hypoplasias were found in this study. The percentage of visible enamel formation time affected by growth disturbances was the parameter that identified the greatest number of significant differences among the subgroups examined. Am J Phys Anthropol, 2005. © 2005 Wiley‐Liss, Inc.
Cellulose: Fascinating Biopolymer and Sustainable Raw Material
Authors: Klemm Dieter , Heublein Brigitte , Fink Hans‐Peter , Bohn Andreas
Published: April 2005

As the most important skeletal component in plants, the polysaccharide cellulose is an almost inexhaustible polymeric raw material with fascinating structure and properties. Formed by the repeated connection of D‐glucose building blocks, the highly functionalized, linear stiff‐chain homopolymer is characterized by its hydrophilicity, chirality, biodegradability, broad chemical modifying capacity, and its formation of versatile semicrystalline fiber morphologies. In view of the considerable increase in interdisciplinary cellulose research and product development over the past decade worldwide, this paper assembles the current knowledge in the structure and chemistry of cellulose, and in the development of innovative cellulose esters and ethers for coatings, films, membranes, building materials, drilling techniques, pharmaceuticals, and foodstuffs. New frontiers, including environmentally friendly cellulose fiber technologies, bacterial cellulose biomaterials, and in‐vitro syntheses of cellulose are highlighted together with future aims, strategies, and perspectives of cellulose research and its applications.
Directionality of pre‐ and post‐breeding migrations of a marbled newt population (Triturus marmoratus): implications for buffer zone management
Authors: Marty P. , AngÉlibert S. , Giani N. , Joly P.
Published: April 2005

The marbled newt, Triturus marmoratus, is a vulnerable urodele species (listed on Annex IV of the European Habitats Directive). However, biological information about their migration and the terrestrial habitats they use is relatively scarce. In order to investigate the influence of the surrounding habitats of a local pond on the directions of pre‐ and post‐breeding migrations, adult newts were monitored over two successive years (from February 2000 to June 2001) at a permanent pond in south‐western France using a drift fence and pitfall traps.

In both sexes the entry and exit directions were non‐randomly distributed. Furthermore, males and females generally followed similar directions facing an oak forest and avoiding barren areas. However, the directions followed by postbreeding migrants leaving the pond differed from those they followed when coming to the pond.

The distribution of captures around the pond was related to environmental factors, and more precisely to vegetation within the immediate surroundings of the pond.

The environmental conditions occurring at the end of the spring postbreeding migration differed greatly from those occurring during the winter prebreeding migration. Thus, vegetation does not exert similar attraction during the two migration periods.

This raises the importance of microhabitat diversity in the vicinity of the breeding pond, which provides a wide range of suitable shelters in different migration periods. Conservation planning must take into account the ecological requirements of this endangered species in managing buffer zones around the breeding sites.

Copyright © 2005 John Wiley & Sons, Ltd.
Lake habitat suitability for the rare European macrophyte Najas flexilis (Willd.) Rostk. & Schmidt
Authors: Wingfield Ruth , Murphy Kevin , Gaywood Martin
Published: April 2005

Najas flexilis (Willd.) Rostk. & Schmidt is a submerged annual macrophyte, rare in Europe, which is protected under the EC Habitats Directive.

N. flexilis grows in deep, often coloured or turbid water in mesotrophic lakes. Because of this habitat preference it is difficult to locate and assess the ecological state of populations of the species for conservation monitoring purposes.

A method is described based on plant community information that can be used to determine the baseline probability that conditions in a lake are suitable for supporting N. flexilis growth. This can be applied to conservation management decisions, such as whether a detailed underwater survey is justified for monitoring the integrity of existing populations of N. flexilis, or whether the lake may be a suitable site for introduction, or reintroduction, of populations of the plant.

Two methods of plant community description are compared: a quantitative micro‐habitat scale approach and a whole‐lake‐scale qualitative approach. Plant community data collected using each method were grouped using TWINSPAN, and environmental descriptors of the sites comprising each plant community group were compared statistically.

Micro‐habitat‐scale community groups differed significantly only in the light extinction coefficient, indicating the zone within the lake in which N. flexilis occurred.

The whole‐lake‐scale community groups differed in a number of environmental variables indicative of eutrophication and acidification, two major environmental threats to N. flexilis survival.

This study suggests that a lake‐scale qualitative plant community description would be a better indicator of site suitability for N. flexilis growth than a quantitative micro‐habitat plant community description. This is because the whole‐lake‐scale approach could detect a difference in the environmental factors that affect N. flexilis growth, which the micro‐habitat scale approach could not.

Copyright © 2005 John Wiley & Sons, Ltd.
On physical realizability and uncertainty of numerical solutions
Authors: Dörnbrack Andreas , Doyle James D. , Lane Todd P. , Sharman Robert D. , Smolarkiewicz Piotr K.
Published: April 2005

Numerical experiments of the stratified flow past a bell‐shaped mountain with a shallow shear layer aloft are performed. Two different approximations of the entropy equation (explicit vs implicit numerical treatment of gravity waves) lead to a substantial discrepancy of the numerical results. As the flow is metastable, it turns out that both solutions are physically realizable and the quality of the solution changes in response to small variations in the accuracy of the numerical approximation. Copyright © 2005 Royal Meteorological Society
Semi‐operational rainfall observations with X‐band multi‐parameter radar
Authors: Maki Masayuki , Iwanami Koyuru , Misumi Ryohei , Park Sang‐Goon , Moriwaki Hiromu , Maruyama Ken‐ichi , Watabe Isao , Lee Dong‐In , Jang Min , Kim Hyo‐Kyung , Bringi V. N. , Uyeda Hiroshi
Published: April 2005

Three‐year semi‐operational observations of rainfall distributions with NIED X‐band multi‐parameter (or polarimetric) radar started in the Kanto area of Japan from July 2003. The purposes and outlines of the radar observations with networks of rain gauges and disdrometers for ground validations are described. Preliminary results of validation analysis of polarimetric rain rate estimators show the usefulness of X‐band multi‐parameter radar for hydrological and meteorological applications in a small area. Copyright © 2005 Royal Meteorological Society
Radar rainfall estimation in the New Zealand context
Authors: Gray Warren , Larsen Howard
Published: April 2005

Difficulties commonly encountered in precipitation measurement by radar include errors from radar reflections from the surface, errors in extrapolating from measurements aloft, and errors through inadequately sampling a fluctuating signal. These error sources are discussed, along with the skill of the solutions that have been implemented. Copyright © 2005 Royal Meteorological Society
Errors in surface rainfall rates retrieved from radar due to wind‐drift
Authors: Lack Steven A. , Fox Neil I.
Published: April 2005

This article describes a series of experiments based on real data wherein the advection of the precipitation below the radar‐sampled volume is estimated using Doppler radar determined wind fields. The experiments show that even at standard resolutions of 2 km the error can be extensive, and at higher resolutions and greater ranges (higher beam elevations) the errors become very large. Errors are assessed using different Z–R relationships and resolutions as high as 0.5 km. Copyright © 2005 Royal Meteorological Society
Evaluation of potential benefit of assimilation of SEVIRI water vapour radiance data from Meteosat‐8 into global numerical weather prediction analyses
Authors: Szyndel M. D. E. , Kelly G. , Thépaut J.N.
Published: April 2005

The clear sky radiance product from the SEVIRI instrument is described. The characteristics of the data derived from water vapour–sensitive channels are discussed. A trial of the assimilation of these data from Meteosat‐8 into the ECMWF NWP model is described and results of this trial presented and discussed. Copyright © 2005 Royal Meteorological Society
Production of recombinant proteins by vaccinia virus in a microcarrier based mammalian cell perfusion bioreactor
Authors: Bleckwenn Nicole A. , Golding Hana , Bentley William E. , Shiloach Joseph
Published: April 2005

The HeLa cell‐vaccinia virus expression system was evaluated for the production of recombinant proteins (enhanced green fluorescent protein (EGFP) and HIV envelope coat protein, gp120) using microcarriers in 1.5 L perfused bioreactor cultures. Perfusion was achieved by use of an alternating tangential flow device (ATF), increasing the length of the exponential phase by 50 h compared to batch culture and increasing the maximum cell density from 1.5 × 106 to 4.4 × 106 cell/mL. A seed train expansion method using cells harvested from microcarrier culture and reseeding onto fresh carriers was developed. EGFP was first used as a model protein to study process parameters affecting protein yield, specifically dissolved oxygen (DO) and temperature during the production phase. The highest level of EGFP, 12 ± 1.5 μg/106 infected cells, was obtained at 50% DO and 31°C. These setpoints were then used to produce glycoprotein, gp120, which was purified and deglycosylated, revealing a significant amount of N‐linked glycosylation. Also, biological activity was assayed, resulting in an ID50 of 3.1 μg/mL, which is comparable to previous reports. Published 2005 Wiley‐Periodicals, Inc.
Two‐year follow‐up intravascular ultrasound analysis after bare metal stent implantation in 120 lesions
Authors: Hong Myeong‐Ki , Lee Cheol Whan , Kim Young‐Hak , Lee Bong‐Ki , Kim Min‐Kyu , Yang Tae‐Hyun , Song Jong‐Min , Han Ki‐Hoon , Kang Duk‐Hyun , Song Jae‐Kwan , Kim Jae‐Joong , Park Seong‐Wook , Park Seung‐Jung
Published: April 2005

The objective of this study was to examine long‐term changes after bare metal stent implantation in a relatively large number of patients. There are few reports of intravascular ultrasound (IVUS) studies performed on stented and nonstented (reference) segments beyond 6 months after bare metal stenting. Using IVUS, we evaluated serial changes in stented and reference segments between 6 and 24 months after stent implantation in 110 patients with 120 lesions. Serial IVUS images were acquired at five equidistant intrastent sites and at two different reference segment sites. Measurements were made of the external elastic membrane (EEM), stent, lumen, and intimal hyperplasia (IH = stent − lumen) area. For the whole patient group, between 6 and 24 months, the mean IH area in stented segments decreased from 2.6 ± 1.0 to 2.3 36± 0.9 mm2 (P < 0.001), and the mean lumen area increased from 6.2 ± 2.0 to 6.5 ± 1.9 mm2 (P < 0.001). The mean IH area decreased in 91 lesions (76%) and increased in 29 lesions (24%) between 6 and 24 months. There were no significant changes in EEM or lumen area in the reference segments. Late angiographic restenosis (diameter stenosis ≥ 50%) occurred in three lesions between 6 and 24 months. A late target lesion revascularization was performed for one lesion. In the period of time between 6 and 24 months after stenting, IH regression occurred in most (76%) stent lesions, resulting in late lumen increase. However, IH progression was observed in 24% of in‐stent lesions. No significant changes of EEM or lumen area occurred in the reference segments. © 2005 Wiley‐Liss, Inc.
Effect of Agitation Intensity on Protein Solubility Behavior
Authors: Kaghazchi T. , Vaezi F. , Ravanchi M. T.
Published: April 2005

A biochemical engineering framework to study fractional protein precipitation has been developed. For optimization, design and safe operation of the fractional protein precipitation process, the effects of process variables must be known. The solubility behavior of trypsin from bovine pancreas, as a function of ammonium sulphate concentration has been examined. The effect of agitation speed on enzyme and total protein solubility and enzyme specific activity has been investigated.
Aeration of Large Size Tanks by a Surface Agitator
Authors: Sardeing R. , Poux M. , Melen S. , Avrillier P. , Xuereb C.
Published: April 2005

A new device has been developed in order to achieve urban or industrial wastewater biological treatment. It has been designed specially for lagoon applications to oxygenate and mix with the same apparatus. The goal is both to achieve a high gas flooding rate and to reach a maximal depth with the bubble plume. Mass transfer measurements have allowed us to choose the most appropriate geometry. Considering the application of the device and the possible use of low‐pressure O2 produced on‐site, the agitation system is located close to the liquid surface and is composed of a gas‐inducing turbine. The role of propellers in addition to the gas‐inducing turbine, as well as the use of baffles and a shell, have been experimentally studied. Numerical simulations (CFD) of the whole apparatus in single‐phase flow have been used to study the influence of the stator part of the geometry.
Optically Active Oligomer Units in Aggregates of a Highly Unsaturated, Optically Inactive Carotenoid Phospholipid
Authors: Foss Bente Jeanette , Sliwka Hans‐Richard , Partali Vassilia , Köpsel Christian , Mayer Bernhard , Martin Hans‐Dieter , Zsila Ferenc , Bikadi Zsolt , Simonyi Miklos
Published: April 2005

Enantiomers of glycerophospholipids show low or no optical activity. Accordingly, optical activity was not observed with the R enantiomer of a highly unsaturated carotenoyl lysophospholipid in solution. In spite of this, strong Cotton effects are detected in water. The amphiphilic carotenoid–phospholipid monomers associate to form aggregates, whose optical activity is attributed to oligomeric entities. These small helical assemblies cannot exist independently. Yet, the calculated octamer represents the simplest repeating primary unit that sufficiently expresses the absorption properties and supramolecular optical activity.
Spectroscopic Evidence for a Dinitrogen Complex of Gallium and Estimation of the GaN2 Bond Strength
Authors: Himmel Hans‐Jörg , Hebben Nicole
Published: April 2005

Matrix‐isolation experiments were performed to study the interaction between Ga atoms and N2 by using Raman and UV/Vis spectroscopies for detection and analysis. It was revealed that a weak complex is formed, for which resonance Raman spectra were obtained. Several overtones were sighted, allowing a rough estimate of the GaN2 fragmentation energy to be made (∼19 kJ mol−1). The excitation profile obtained from the spectra at different laser wavelengths agrees with the UV/Vis spectrum and shows that the complex exhibits an electronic transition at around 410 nm. At the Ga atom, this transition can be described as a 2S←2P or 2D←2P excitation, which is red‐shifted from its position for free Ga atoms (approximately 340 nm and 270 nm for 2S←2P and 2D←2P, respectively) as a result of N2 complexation. The effect of complexation involves, therefore, only slight stabilization of the 2P ground state but relatively strong stabilization of the excited 2S state. Accordingly, for the Ga atom in its excited 2S state, the GaN2 bond energy can be estimated to be around 79 kJ mol−1.
Electronic Structure, Spectra, and Magnetic Circular Dichroism of Cyclohexa‐, Cyclohepta‐, and Cyclooctapyrrole
Authors: Gorski Alexander , Köhler Thomas , Seidel Daniel , Lee Jeong Tae , Orzanowska Grażyna , Sessler Jonathan L. , Waluk Jacek
Published: April 2005

Three recently obtained expanded porphyrins represent nice examples of compounds for which the electronic and spectral properties can be predicted from symmetry considerations alone. Perimeter‐model‐based theoretical analysis of the electronic structure of doubly protonated cyclo[6], cyclo[7], and cyclo[8]pyrrole leads to the anticipation of qualitatively the same electronic absorption and magnetic circular dichroism patterns for all three compounds. These predictions are fully confirmed by experiments, as well as DFT and INDO/S calculations. Due to a characteristic pattern of frontier molecular orbitals, a degenerate HOMO and a strongly split LUMO pair, the three cyclopyrroles show comparable absorption intensity in the Q and Soret regions. Magnetic circular dichroism spectra reveal both A and B Faraday terms, of which the signs and magnitudes are in remarkably good agreement with theoretical expectations. The values of the magnetic moments of the two lowest degenerate excited states have also been obtained.
High Affinity, Sequence Specific DNA Binding by Synthetic Tripyrrole–Peptide Conjugates
Authors: Blanco Juan B. , Vázquez Olalla , Martínez‐Costas José , Castedo Luis , Mascareñas José L.
Published: April 2005

Linking the basic region of a bZIP transcription factor to a distamycin‐like tripyrrole peptide by means of a nitrogen‐containing tether produces a hybrid capable of high‐affinity recognition of specific, designated DNA sequences. The importance of the nitrogen in the tether is shown by the considerable reduction in affinity (more than 10‐fold) caused by its replacement with an ether linkage. Attachment of an aminopropyl chain on the pyrrole adjacent to the pyrrole bearing the nitrogen‐containing tether increases affinity approximately one order of magnitude. These results confirm that a suitable location of protonated amine groups on designed DNA‐binding peptides provides for higher affinities, most probably because of the generation of salt bridged contacts with the phosphodiester backbone.
Efficient Solid‐Phase Synthesis of Peptide‐Based Phosphine Ligands: Towards Combinatorial Libraries of Selective Transition Metal Catalysts
Authors: Christensen Christian A. , Meldal Morten
Published: April 2005

A new methodology for the solid‐phase synthesis of peptide‐based phosphine ligands has been developed. Solid supported peptide scaffolds possessing either primary or secondary amines were synthesised using commercially available Fmoc‐protected amino acids and readily available Fmoc‐protected amino aldehydes for reductive alkylation, in standard solid‐phase peptide synthesis (SPPS). Phosphine moieties were introduced by phosphinomethylation of the free amines as the final solid‐phase synthetic step, immediately prior to complexation with palladium(II), thus avoiding tedious protection/deprotection of the phosphine moieties during the synthesis of the ligands. The extensive use of commercial building blocks and standard SPPS makes this methodology well suited for the generation of solid‐phase combinatorial libraries of novel ligands. Furthermore, it is possible to generate several different phosphine ligand libraries for every peptide scaffold library synthesised, by functionalising the scaffold libraries with different phosphine moieties. The synthesised ligands were characterised on solid support by conventional 31P NMR spectroscopy and, cleaved from the support, as their phosphine oxides by HPLC, 1H NMR, 31P NMR and high resolution ESMS. Palladium(II) allyl complexes were generated from the resin bound ligands and to demonstrate their catalytic properties, palladium catalysed asymmetric allylic substitution reactions were performed. Good yields and moderate enantioselectivity was obtained for the selected combination of catalysts and substrate, but most importantly the concept of this new methodology was proven. Screening of ligand libraries should afford more selective catalysts.
Supratentorial extraventricular ependymal neoplasms
Authors: Shuangshoti Shanop , Rushing Elisabeth J. , Mena Hernando , Olsen Cara , Sandberg Glenn D.
Published: April 2005

BACKGROUND

Published research on the clinicopathologic features of extraventricular ependymal neoplasms of the cerebral hemispheres has been scant.

METHODS

Thirty‐two archival cases were studied to investigate the prognostic impact of clinicopathologic parameters including flow cytometry, the proliferation (Ki‐67) labeling index, and p53 expression.

RESULTS

Among these 32 cases were 2 subependymomas, 19 ependymomas, and 11 anaplastic ependymomas. No significant gender predilection was observed, and 45% of patients were in their second or third decade of life. The left cerebral hemisphere was 1.5 times more commonly involved. On available imaging studies, lesions were often cystic, with or without a mural nodule. Tumors expressed glial fibrillary acidic protein (87%), S‐100 protein (77%), cytokeratin (43%), and epithelial membrane antigen (17%). Ki‐67 proliferation index paralleled tumor grade. Immunoreactivity for p53 protein was observed in the 2 cases of subependymoma, in 10 of 11 anaplastic ependymomas, and in 6 of 17 ependymomas. Flow cytometry performed in 27 tumors revealed diploidy in 20 cases and aneuploidy in 4 cases (3 anaplastic and 1 classic ependymomas), with S‐phase fraction ranging from 0.2–9.7. Eleven subjects were additionally treated with radiotherapy, and 3 with chemotherapy. Follow up was available in 25 (78%) patients.

CONCLUSIONS

The results of the current study suggest that there is no significant relation between histopathology, Ki‐67 proliferation index, p53 immunolabeling, tumor ploidy, and biologic behavior. Cancer 2005. Published 2005 by the American Cancer Society.
Distribution and abundance of metabotropic glutamate receptor subtype 2 in rat brain revealed by [3H]LY354740 binding in vitro and quantitative radioautography: Correlation with the sites of synthesis, expression, and agonist stimulation of [35S]GTPγs binding
Authors: Richards Grayson , Messer Jürg , Malherbe Pari , Pink Richard , Brockhaus Manfred , Stadler Heinz , Wichmann Jürgen , Schaffhauser Hervé , Mutel Vincent
Published: April 2005

Until recently, there was a lack of selective radioligands for the subtypes of metabotropic glutamate (mGlu) receptors. [3H]LY354740 ((+)‐2‐aminobicyclo[3,1,0]hexane‐2,6‐dicarboxylic acid), a selective agonist for group II receptors (mGlu2 and ‐3, which are negatively coupled to cAMP production), has now been used to map their brain distribution and abundance by in vitro binding and quantitative radioautography. The selective cation dependence of its binding allowed the discrimination between mGlu2 and mGlu3 receptor labeling. Thus, in the presence of Ca2+ and Mg2+ ions, the agonist bound selectively to mGlu2 receptors as evidenced by: 1) the correlative distribution and abundance of binding sites (highest in the lacunosum moleculare of the hippocampus and lowest in white matter) with mGlu2 receptor mRNA and protein revealed by in situ hybridization histochemistry and immunohistochemistry, respectively; 2) its selective pharmacology; and 3) the distribution of LY354740‐stimulated [35S]GTPγS binding (25–97% above basal, according to the brain region), revealing G protein‐coupled receptor coupling to Gi proteins. Nonspecific binding (in the presence of 10 μM DCG‐IV, a group II‐selective, mGlu2‐preferring, receptor agonist) was <10% of total. In adjacent sections, the distribution of binding sites for [3H]DCG‐IV was very similar. This extensive study paves the way for investigations of the regional expression and regulation of mGlu2 receptors in human CNS diseases, such as Alzheimer's disease, which may reveal their functional roles and identify potential therapeutic drug targets. Indeed, it has recently been demonstrated (Higgins et al. [2004] Neuropharmacology 46:907–917) that pharmacological manipulation of mGlu2 receptors influences cognitive performance in the rodent. J. Comp. Neurol. 487:15–27, 2005. © 2005 Wiley‐Liss, Inc.
Photoactivatable green fluorescent protein as a single‐cell marker in living embryos
Authors: Stark Danny A. , Kulesa Paul M.
Published: April 2005

Selective marking of a single cell within an embryo is often difficult to perform with existing methods. Here, we report a minimally invasive optical technique that uses 405‐nm laser light to photoactivate a variant of green fluorescent protein (PAGFP). Single cells and small groups of cells (n < 10) are successfully marked, from a region of cells injected and electroporated with PAGFP, in both whole chick embryo explants and in ovo. Photoactivated cells display normal cell migratory behaviors and retain a bright GFP signal for at least 24 hr when followed with confocal time‐lapse microscopy. We determined that using a low‐magnification objective (∼ ×10) and low laser power (∼1–10%) leads to a steady increase in fluorescence signal within a photoactivated cell and minimizes photobleaching. The utility of PAGFP photoactivation was tested to address a specific question in developmental biology. Specifically, we asked whether neighboring migratory cells that emerge from the hindbrain and invade surrounding peripheral tissues maintain neighbor relationships while traveling to the destination sites. We found that some neural crest do not maintain neighbor relationships, such that two neighboring cells near the neural tube cells may populate different branchial arches. The ability to optically photoactivate PAGFP in a single or small group of cells and follow individual cell migratory behaviors within a living embryo offers a powerful, minimally invasive cell marking tool for precise, in vivo cell migration studies. Developmental Dynamics 233:983–992, 2005. © 2005 Wiley‐Liss, Inc.
Conserved expression of a novel gene during gonadal development
Authors: Hudson Quanah J. , Smith Craig A. , Sinclair Andrew H.
Published: April 2005

We isolated the novel gene Gonad Expressed Transcript (GET) from a chicken embryonic gonad library enriched for differentially expressed male transcripts. Chicken GET encodes a predicted protein containing a Pfam‐B 30624 domain with homology to a putative orthologue in mammals. Chicken GET expression was confined to the developing urogenital system. It was first detected in the glomerulus of the mesonephros of both sexes from embryonic day (E) 2.5. At E4.5, expression switches to the gonad of both sexes and then localizes to the gonadal cortex. We isolated the putative mouse orthologue and examined expression in the mouse embryo. Gonadal expression was conserved. Ovarian expression localized to the cortex as in the chicks. However, in contrast to the chicken, testis expression localized to the cords. In the adult, GET is expressed in the ovary but not the testis of both the chicken and the mouse. Expression of GET in the müllerian duct, wolffian duct, metanephric kidney, and external genitalia, suggests that GET may play a wider role in the development of the urogenital system. Developmental Dynamics 233:1083–1090, 2005. © 2005 Wiley‐Liss, Inc.
Groucho corepressor proteins regulate otic vesicle outgrowth
Authors: Bajoghli Baubak , Aghaallaei Narges , Czerny Thomas
Published: April 2005

The Groucho/Tle family of corepressor proteins is known to regulate multiple developmental pathways. Applying the dominant‐negative effect of the short member Aes, we demonstrate here a critical role of this gene family also for ear development. Misexpression of Aes in medaka embryos resulted in reduced size or loss of otic vesicles, whereas overexpression of the full‐length Groucho protein Tle4 gave the opposite phenotype. These results are in close agreement with phenotypes observed for eye formation, suggesting a similar role for Groucho/Tle proteins in the developmental pathways of both sensory organs. Furthermore, by using the heat‐inducible HSE promoter, we observed reversible branching of the embryonic axis upon Aes misexpression, indicating a transient duplication of the organizer. Groucho proteins, therefore, are critical for organizer maintenance. Developmental Dynamics 233:760–771, 2005 © 2005 Wiley‐Liss, Inc.
Magnetic Anisotropy of New Layered Copper(II) Bromide Complexes of 1‐Substituted Tetrazoles
Authors: Shvedenkov Yurii , Bushuev Mark , Romanenko Galina , Lavrenova Ludmila , Ikorskii Vladimir , Gaponik Pavel , Larionov Stanislav
Published: April 2005

Two new isostructural complexes, dibromobis(1‐ethyltetrazole)copper(II) (1) and dibromobis(1‐hexyltetrazole)copper(II) (2), have been synthesised. Each bromine atom in the crystal structure of 1 and 2 is bonded to two copper atoms to give rise to a polymeric corrugated network. The polymeric layers are distinctly separated by tetrazole ligands. Both solids exhibit a phase transition to the ferromagnetic state with Curie temperatures of 8.5 K and 8.9 K for 1 and 2, respectively, and a strong anisotropy of the magnetic susceptibility below the ordering temperature. The easy magnetisation axis lies along the monoclinic axis, and the hard magnetisation axis is orthogonal to the polymeric layers. Effective anisotropy fields were estimated as (720–3020 Oe). (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005)
New Layered Polymeric Metamagnet Based on Copper(II) Complex with3‐Imidazoline Nitroxide
Authors: Burdukov Alexei , Shvedenkov Yurii , Pervukhina Natalie , Reznikov Vladimir
Published: April 2005

A new complex, bis[4‐(2‐oxido‐1‐butenyl)‐2,2,5,5‐tetramethylimidazolidine‐1‐oxyl]copper(II) (CuLEt2), has been synthesized. The synthesis, characterization, and magnetic properties as well as the crystal structure of CuLEt2 have been studied. The layered solid of the complex possesses a metamagnetic phase transition at 4.5 K and shows strong anisotropy of magnetic properties below the ordering temperature. The easy magnetization axis lies along the b axis. The hard magnetization axis is orthogonal to the polymeric layers. Effective anisotropy fields have been estimated (H⟂ = 1390 Oe, H∥ = 420 Oe). (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005)
Do Sodium Oxofluoroaluminates Exist at Room Temperature?
Authors: Kucharík Marián , Boča Miroslav , Bessada Catherine , Fuess Hartmut
Published: April 2005

Alumina dissolution in cryolite melts is currently associated with the formation of oxofluorospecies. Mixtures of Na3AlF6 and Al2O3 were heated under different conditions of temperature, time and atmosphere. The existence of oxofluorospecies in solidified samples at room temperature was investigated by X‐ray diffraction, IR and Magic Angle Spinning NMR spectroscopy. The formation of β‐alumina (NaAl11O17) was detected depending on the heating conditions, but no oxofluoroaluminate species were found. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005)
Kinetics of Cyclooctene Epoxidation with tert‐Butyl Hydroperoxide in the Presence of [MoO2X2L]‐Type Catalysts (L = Bidentate Lewis Base)
Authors: Al‐Ajlouni Ahmad , Valente Anabela A. , Nunes Carla D. , Pillinger Martyn , Santos Ana M. , Zhao Jin , Romão Carlos C. , Gonçalves Isabel S. , Kühn Fritz E.
Published: April 2005

MoVI complexes with the general formula [MoO2X2L] [X = Cl, Br; L = 4,4'‐dimethyl‐2,2'‐bipyridine (dmbp) or 4‐hexyl‐4'‐methyl‐2,2'‐bipyridine (hmbp)] have been prepared and characterized by IR and solution NMR (1H, 13C, 17O and 95Mo) spectroscopy. The complexes were applied as catalysts in the homogeneous phase for the epoxidation of cyclooctene, with tert‐butyl hydroperoxide (TBHP) as the oxygen source. The desired epoxide was the only product and turnover frequencies of up to about 9000 h–1 could be reached. The catalytic activities increased in the order [MoO2Br2(dmbp)] < [MoO2Br2(hmbp)] < [MoO2Cl2(dmbp)] < [MoO2Cl2(hmbp)]. A kinetic model was built up for a homogeneous batch reactor based on a simplified mechanism involving three steps: (i) reversible coordination of TBHP to the starting MoVI complex to give a MoVI alkylperoxide; (ii) irreversible oxidation of cyclooctene to cyclooctene oxide by the species formed in step 1, with formation of the starting complex and tert‐butyl alcohol; (iii) reversible coordination of tert‐butyl alcohol to the starting complex. This model is consistent with the observed kinetics. The first step in this reaction mechanism was characterized in more detail by studying the kinetics of the reaction of the starting complexes with TBHP in the absence of any reductant by UV/Vis spectroscopy. Rate constants, equilibrium constants, and activation parameters were determined. All ΔS‡ values were negative and therefore support an associative mechanism in which a seven‐coordinate intermediate is formed. The results also suggest that the first step is not always the rate‐limiting step of cyclooctene epoxidation with these complexes. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005)
Two New μ‐(1,3‐Azido)‐Bridged Polymers: Alternating Single and Double Bridges in a 1D Nickel(II) Complex and Uniform Bridge in a 2D Copper(II) Complex: Syntheses, Single‐Crystal Structures and Magnetic Studies
Authors: Manna Subal Chandra , Konar Sanjit , Zangrando Ennio , Drew Michael G. B. , Ribas Joan , Ray Chaudhuri Nirmalendu
Published: April 2005

Two polymeric azido bridged complexes [Ni2L2(N3)3]n(ClO4)n (1) and [Cu(bpds)2(N3)]n(ClO4)n(H2O)2.5n (2) [L = Schiff base, obtained from the condensation of pyridine‐2‐aldehyde with N,N,2,2‐tetramethyl‐1,3‐propanediamine; bpds = 4,4'‐bipyridyl disulfide] have been synthesized and their crystal structures have been determined. Complex 1, C26H42ClN15Ni2O4, crystallizes in a triclinic system, space group P$\tilde {1}$ with a = 8.089(13), b = 9.392(14), c = 12.267(18) Å, α = 107.28(1), β = 95.95(1), γ = 96.92(1)° and Z = 2; complex 2, C20H21ClCuN7O6.5S4, crystallizes in an orthorhombic system, space group Pnna with a = 10.839(14), b = 13.208(17), c = 19.75(2) Å and Z = 4. The crystal structure of 1 consists of 1D polymers of nickel(L) units, alternatively connected by single and double bridging μ‐(1,3‐N3) ligand with isolated perchlorate anions. Variable temperature magnetic susceptibility data of the complex have been measured and the fitting of magnetic data was carried out applying the Borrás‐Almenar formula for such types of alternating one‐dimensional S = 1 systems, based on the Hamiltonian H = –JΣ(S2iS2i–1 + αS2iS2i+1). The best‐fit parameters obtained are J =–106.7  ± 2 cm–1; α = 0.82 ± 0.02; g = 2.21 ± 0.02. Complex 2 is a 2D network of 4,4 topology with the nodes occupied by the CuII ions, and the edges formed by single azide and double bpds connectors. The perchlorate anions are located between pairs of bpds. The magnetic data have been fitted considering the complex as a pseudo‐one‐dimensional system, with all copper(II) atoms linked by μ(1,3‐azido) bridging ligands at axial positions (long Cu···N3 distances) since the coupling through long bpds is almost nil. The best‐fit parameters obtained with this model are J = –1.21 ± 0.2 cm–1, g = 2.14 ± 0.02. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005)