bluuebunny/crossref_metadata_2025 huggingface dataset:
Leptin receptor expression and in vitro leptin actions on prostaglandin release and nitric oxide synthase activity in the rabbit oviduct
Authors: Zerani M , Boiti C , Dall’Aglio C , Pascucci L , Maranesi M , Brecchia G , Mariottini C , Guelfi G , Zampini D , Gobbetti A
Published: April 2005

In this study, we have examined the presence and the distribution of receptors for leptin (Ob-R) in the oviduct of rabbits, and the effects of leptin on the release of prostaglandin (PG) F2α and PGE2 and on the activity of nitric oxide (NO) synthase (NOS) by oviducts cultured in vitro. Rabbits were killed during the follicular phase and the oviducts were incubated in vitro with leptin, PGF2α, PGE2, NO donor and inhibitors of NOS and cyclo-oxigenase (COX). Using immunohistochemistry, Ob-R-like positive reaction was observed only in the cytoplasm of secretory cells, having stronger intensity in the infundibulum and ampulla tracts than in the isthmus. Both leptin and NO donor inhibited PGE2 release, whereas they enhanced PGF2α release; NOS inhibitor alone or with leptin increased PGE2 and decreased PGF2α production; NOS activity was enhanced by leptin, while PGs did not affect this enzyme. This study suggests that the oviduct could be a potential target for endocrine regulation by leptin, whose circulating levels may act as a metabolic signal modulating oviductal PG release through mediation of the NOS/NO system.
Specific binding of 4-hydroxyestradiol to mouse uterine protein: evidence of a physiological role for 4-hydroxyestradiol
Authors: Markides C S A , Liehr J G
Published: April 2005

There are several indications of a possible physiological role for 4-hydroxyestradiol (4-OHE2) in hormone-responsive tissues. To examine a hormonal activity of 4-OHE2, we have studied the binding of 3H-labeled 4-OHE2 to mouse uterine cytosolic protein. In uteri of 3-week-old mice, total binding was 319.4 ± 13.9 fmol/mg protein. Binding in the presence of excess unlabeled 4-OHE2 dropped to 82.1 ± 1.7 fmol/mg protein, whereas 214.6 ± 9.4 fmol/mg protein bound while incubating in an excess of unlabeled 17β-estradiol (E2). The difference between the two binding values in the presence of excess steroid (132.5 ± 11.1 fmol/mg protein) is taken as selective binding of 4-OHE2 to a specific protein. In mice older than 4 weeks, the specific 4-OHE2 binding declined: 32.0 ± 4.0 fmol/mg protein at 8 weeks, 54.8 ± 6.3 fmol/mg protein at 12 weeks and 54.6 ± 5.2 fmol/mg protein at 9 months. Of other organs tested (liver, kidney, lung and whole brain) only lung showed significant selective binding of 4-OHE2. When E2-binding sites are blocked, binding follows first-order kinetics, yielding a dissociation constant (Kd) value of 11.8 ± 2.1 nM. The specific binding of 4-OHE2 was not inhibited by any other steroids or estrogen metabolites that were tested, except for 2-hydroxyestradiol (2-OHE2), which displayed competitive inhibition of 4-OHE2 binding with an inhibition constant (Ki) value of 98.2 ± 12.6 nM. These results lead us to conclude that 4-OHE2 binds to a specific binding protein, distinct and different from binding to estrogen receptors (ERα and ERβ). The physiological role of this binding remains to be elucidated.
NEPH2 Is Located at the Glomerular Slit Diaphragm, Interacts with Nephrin and Is Cleaved from Podocytes by Metalloproteinases
Authors: Gerke Peter , Sellin Lorenz , Kretz Oliver , Petraschka Daniel , Zentgraf Hanswalter , Benzing Thomas , Walz Gerd
Published: April 2005

The NEPH family comprises three transmembrane proteins of the Ig superfamily interacting with the glomerular slit diaphragm proteins podocin and ZO-1. NEPH1 binds to nephrin, another component of the slit diaphragm, and loss of either partner causes heavy proteinuria. NEPH2, which is strongly conserved among a large number of species, is also expressed in the kidney; however, its function is unknown. The authors raised NEPH2 antisera to demonstrate NEPH2 expression in a variety of mouse tissues, including the kidney and a podocyte cell line. The authors localized the expression of NEPH2 to the glomerular slit diaphragm by electron microscopy and show NEPH2 homodimerization and specific interactions with the extracellular domain of nephrin

in vitro

and

in vivo

. NEPH1, however, failed to interact with NEPH2. The authors detected immunoreactive NEPH2 in urine of healthy subjects, suggesting that the extracellular domain is cleaved under physiologic conditions. These findings were confirmed

in vitro

in podocyte cell culture. Shedding is increased by tyrosine phosphatase inhibitors and diminished by GM6001, an inhibitor of metalloproteinases. Overexpression experiments indicate an involvement of the MT1-matrix metalloproteinase. The results suggest a role for NEPH2 in the organization and/or maintenance of the glomerular slit diaphragm that may differ from the functions of NEPH1 and nephrin.
Low-coherence interferometry – an advanced technique for optical metrology in industry
Authors: Dufour M L , Lamouche G , Detalle V , Gauthier B , Sammut P
Published: April 2005

Low-coherence interferometry (LCI) is an optical technique that may be used for industrial surface metrology with accuracy in the micron range. An instrument made with optical fibres is rugged enough to be used in industrial environments and the fibre-linked optical probe may be miniaturised
for accessing tight locations. Among industrial applications developed at IMI, several cases for which LCI has been particularly useful, such as an elongational rheometer (RME), characterisation of wear damages on coating and laser-induced breakdown spectroscopy (LIBS), will be presented.
The RME is an instrument in which a polymer sample is stretched in a controlled temperature furnace at up to 350°C. LCI has been used for monitoring the thickness of the samples. Wear damage is quantified by the volume loss after a wear test. It requires a high depth resolution (axis perpendicular
to the surface) but a relatively coarse transverse resolution. The LIBS is a technique that has been used for analysing the chemical composition of materials as a function of depth. LCI has been integrated to a LIBS instrument for measuring accurately the crater depth between each laser shot.
Clinical Performance of a Regenerative Strategy for Intrabony Defects: Scientific Evidence and Clinical Experience
Authors: Cortellini Pierpaolo , Tonetti Maurizio S.
Published: April 2005

Background: The aim of the present study was to evaluate the clinical performance of a regenerative strategy for the treatment of deep intrabony defects.

Methods: This patient cohort study involved 40 patients with one deep interdental intrabony defect each. They were treated with periodontal regeneration using four different regenerative methods (expanded polytetrafluoroethylene [ePTFE] titanium reinforced membranes, bioabsorbable membranes alone, bioabsorbable membranes with a bone replacement graft [combination], or enamel matrix derivative), according to predefined criteria and decision‐making algorithms. Defects were accessed with papilla preservation flaps performed with the aid of an operating microscope and microsurgical instruments. A stringent plaque control regimen was enforced in all the patients during the 1‐year observation period. Outcomes included evaluation of the complete primary closure of the interdental space (CLOSURE), gains in clinical attachment (CAL), and reductions in probing depths (PD).

Results: CLOSURE was achieved in all treated defects and was maintained in 90% of cases for the entire healing period. At 1 year the observed CAL gains were 6 ± 1.8 mm on average, corresponding to a resolution of 92.1% ± 12% of the initial intrabony (CAL%) component of the defect. Average PD reduction was 6.1 ± 1.9 mm and was associated with minimal increase in gingival recession (–0.1 ± 0.7 mm). The 12 sites treated with titanium reinforced ePTFE membranes resulted in a 1‐year CAL gain of 6.8 ± 2.2 mm (CAL%: 94.7 ± 13.4); the 11 cases treated with combination therapy showed a 1‐year CAL gain of 5.4 ± 1.7 mm (CAL%: 88.2 ± 9.6); the seven sites treated with bioabsorbable barriers resulted in 5.9 ± 1.2 mm of CAL gain (CAL%: 88.9 ± 11.5); and the 10 sites treated with enamel matrix gained on average 5.9 ± 1.5 mm of CAL (CAL%: 88.9 ± 11.5). No significant differences were observed among the four approaches.

Conclusion: The use of an evidence‐based regenerative strategy resulted in clinically relevant amounts of CAL gains, shallow pockets, and minimal gingival recession with the four regenerative approaches. J Periodontol 2005;76:341‐350.
Prospective Assessment of the Use of Enamel Matrix Proteins With Minimally Invasive Surgery
Authors: Harrel Stephen K. , Wilson Thomas G. , Nunn Martha E.
Published: April 2005

Background: Minimally invasive surgery (MIS) is a surgical technique using very small incisions, indicated for performing regenerative therapy in periodontal defects. Enamel matrix proteins (EMP) have been shown to enhance periodontal regeneration. This study was undertaken to determine the effect of using EMP in combination with an MIS approach.

Methods: Patients from two private periodontal practices with chronic periodontitis who, following non‐surgical therapy, had one or more sites with probing depths (PD) of ≥6 mm were included in the study. An MIS approach was utilized for surgical access. Following surgical debridement, EMP was placed into the bony defect. The surgical sites were reevaluated after at least 11 months.

Results: Surgical treatment was performed at 160 sites in 16 patients. No significant differences were noted in the results between the two offices and the data were combined. Mean PD reduction (P = 0.002) and attachment level improvements (P = 0.012) were significantly greater than 3 mm with mean post‐surgical PD of 3.17 mm and attachment levels of 4.05 mm, based on subject means. Mean change in recession following surgery was negligible (0.01 mm). All sites were considered to be clinically successful.

Conclusion: The combination of MIS and EMP yields significant reductions in probing depths and improvements in attachment levels while producing little or no increase in recession. J Periodontol 2005;76:380‐384.
Diabetes and Periodontal Disease: A Case‐Control Study
Authors: Campus Guglielmo , Salem Abeer , Uzzau Sergio , Baldoni Edoardo , Tonolo Giancarlo
Published: April 2005

Background: Periodontitis is often associated with diabetes and might be considered one of the chronic complications of diabetes mellitus, both in Type 1 (T1DM) and Type 2 (T2DM). This case‐control study was designed to evaluate the possible association between non–insulin‐dependent diabetes (T2DM) and clinical and microbiological periodontal disease among adult Sardinians.

Methods: A total of 212 individuals participated in this study: 71 T2DM patients aged 61.0 ± 11.0 years and 141 non‐diabetic controls in good general health aged 59.1 ± 9.2 years. All subjects were given a clinical periodontal examination for probing depth, attachment level, presence of calculus, bleeding on probing, and assessment of plaque. Subgingival plaque samples were obtained, and P. gingivalis, P. intermedia, and T. forsythensis were identified using multiplex polymerase chain reaction.

Results: T2DM patients showed a significantly lower number of teeth present (P = 0.002); a significant increase in number of probing depths >4 mm, and percent of pocket depths >4 mm (P = 0.04 and P = 0.05, respectively); periodontitis (P = 0.046); bleeding on probing (P = 0.02); and plaque index (P = 0.01). A significant association with diabetes was detected for plaque (X 2 = 4.46; P <0.05) and bleeding on probing (X 2 = 3.60; P <0.05). Concerning bacteria prevalence, a positive association was detected for P. gingivalis (X 2 = 2.80; P <0.05) and T. forsythensis (X2 = 3.87; P <0.05). Presence of plaque was positively associated with case status (odds ratio [OR] = 1.3; 95% confidence interval [CI]: 1.2, 3.6) and with prevalence of P. gingivalis and T. forsythensis (OR = 1.2, 95% CI: 1.3, 2.2; and 1.2, 95% CI: 1.2, 1.8, respectively).

Conclusion: Patients with T2DM undoubtedly have a susceptibility for more severe periodontal disease. J Periodontol 2005;76: 418‐425.
Clinical Response of Azithromycin as an Adjunct to Non‐Surgical Periodontal Therapy in Smokers
Authors: Mascarenhas Paulo , Gapski Ricardo , Al‐Shammari Khalaf , Hill Roger , Soehren Stephen , Fenno J. Christopher , Giannobile William V. , Wang Hom‐Lay
Published: April 2005

Background: Antibiotic therapy can be used in very specific periodontal treatment situations such as in refractory cases of periodontal disease found to be more prevalent in smokers. This study was designed to determine the efficacy of azithromycin (AZM) when combined with scaling and root planing (SRP) for the treatment of moderate to severe chronic periodontitis in smokers.

Methods: Thirty‐one subjects were enrolled into a 6‐month randomized, single‐masked trial to evaluate clinical, microbial (using benzoyl‐ DL‐arginine naphthylamine [BANA] assay), and gingival crevicular fluid (GCF) pyridinoline cross‐linked carboxyterminal telopeptide of type I collagen (ICTP) levels in response to SRP alone or SRP + AZM. At baseline, patients who smoked ≥1 pack per day of cigarettes who presented with at least five sites with probing depths (PD) of ≥5 mm with bleeding on probing (BOP) were randomized into the test or control groups. At baseline and 3 and 6 months, clinical measurements (probing depth [PD], clinical attachment loss [CAL], and bleeding on probing [BOP]) were performed. GCF bone marker assessment (Ctelopeptide [ICTP] as well as BANA test analyses) were performed at baseline, 14 days, and 3 and 6 months.

Results: The results demonstrated that both groups displayed clinical improvements in PD and CAL that were sustained for 6 months. Using a subject‐based analysis, patients treated with SRP + AZM showed enhanced reductions in PD and gains in CAL at moderate (4 to 6 mm) and deep sites (>6 mm) (P <0.05). Furthermore, SRP + AZM resulted in greater reductions in BANA levels compared to SRP alone (P <0.05) while rebounds in BANA levels were noted in control group at the 6‐month evaluation. No statistically significant differences between groups on mean BOP and ICTP levels during the course of the study were noted.

Conclusions: The utilization of AZM in combination with SRP improves the efficacy of non‐surgical periodontal therapy in reducing probing depth and improving attachment levels in smokers with moderate to advanced attachment loss. J Periodontol 2005;76:426‐436.
Aggressive Periodontitis in an Urban Population in Southern Brazil
Authors: Susin Cristiano , Albandar Jasim M.
Published: April 2005

Background: There are limited data about the epidemiology and risk factors for aggressive periodontitis (AgP) in Latin American and Brazilian populations. The aim of this study was to assess the prevalence of AgP and the risk associated with demographic variables, smoking behavior, and other periodontal variables in a young urban population in southern Brazil.

Methods: A representative sample of 612 subjects aged 14 to 29 years were sampled using a multistage probability method. A full‐mouth clinical examination of six sites per tooth and an interview were performed in a mobile examination center. Subjects in the age groups 14 to 19 years and 20 to 29 years were classified with AgP if they had four or more teeth with attachment loss ≥4 mm or ≥5 mm, respectively.

Results: AgP was found in 5.5% of the subjects. The disease occurred equally among males and females, but was twice as prevalent among non‐whites than whites. In the age groups 20 to 24 years and 25 to 29 years, the AgP subjects had a significantly higher prevalence of tooth loss (90.2% versus 40.4% and 86.1% versus 43.4%, P <0.01) and mean number of missing teeth (2.6 versus 0.9 and 3.4 versus 1.5, P <0.05) than subjects without attachment loss. The AgP subjects also had significantly higher percentages of sites with dental plaque (P <0.0001), gingival bleeding (P <0.05), and supragingival calculus (P <0.0001) than normal subjects. The risk for AgP was higher in the 25‐ to 29‐year than the 14‐ to 19‐year age groups (odds ratio [OR] = 6.2), in the low than middle or high socioeconomic status (OR = 4.5), in moderate or heavy smokers than nonsmokers (OR = 3.1), and in subjects with ≥10% versus <10% sites with supragingival calculus (OR = 3.6).

Conclusion: Socioeconomic status, smoking, and dental calculus were significant risk indicators of aggressive periodontitis in this population. Suitable periodontal prevention programs implementing these risk indicators may prevent or reduce the prevalence of aggressive periodontitis in this and similar populations. J Periodontol 2005;76:468‐475.
Enhancing Thermal Stability, Modulus and Ductility of Magnesium using Molybdenum as Reinforcement
Authors: Wong W.  L. E. , Gupta M.
Published: April 2005

Ductile yet hard magnesium based composites containing varying amount of molybdenum particulates were synthesized using an innovative disintegrated melt deposition route followed by hot extrusion. Good interfacial integrity was observed between molybdenum particulates and the magnesium matrix. The novel Mg‐Mo composites further revealed superior coefficient of thermal expansion and elastic modulus when compared to pure magnesium.
Mesoporous Systems for the Preparation of Ordered Magnetic Nanowire Arrays
Authors: Eliseev A. A. , Kolesnik I. V. , Lukashin A. V. , Tretyakov Y. D.
Published: April 2005

Some tendencies in data storage technologies based on magnetic nanostructures are discussed and a novel approach to anisotropic magnetic nanoparticles which can be used as an active components of magnetic storage media is proposed by the authors
FePt Hard Magnets
Authors: Gutfleisch O. , Lyubina J. , Müller K.‐H. , Schultz L.
Published: April 2005

The FePt alloys have recently attracted considerable attention due to their excellent intrinsic magnetic, chemical and mechanical properties. Their possible usage ranges from permanent magnets for special applications (e.g. in micro‐electro‐mechanical systems, magnetic MEMS, and in aggressive environments) to ultra‐high density magnetic storage media. The article describes general aspects concerning the phase formation and magnetic properties of materials based on the L10 FePt phase. Both thin film and bulk approaches are considered. The production of bulk nanocrystalline Fe100‐xPtx powders by mechanical alloying and subsequent annealing is described. Various combinations of phases, away from thermodynamic equilibrium, have been obtained using this technique.
Deforming Nanocrystalline Metals: New Insights, New Puzzles
Authors: Weissmüller J. , Markmann J.
Published: April 2005

Recent experiments have brought new insights into the mechanisms which govern the plasticity of nanocrystalline metals. In particular, new opportunities have arisen from the finding that bulk nanocrystalline samples with extremely small grain size, prepared by the inert gas condensation technique, can be deformed to large true strain. The findings elucidate the roles of creep, partial dislocation activity along with its consequences, faulting and twinning, as well as grain boundary sliding and grain rotation. However, they also rise intriguing new questions, specifically with respect to the mechanisms of dislocation nucleation at grain boundaries, and with respect to slip system selection and alignment in twinned grains. An emerging insight is that there is not ‘the’ deformation mechanism at small grain size; instead, deformation mechanism maps in, for instance, the parameter space spanned by the strain rate and the grain size, are more appropriate representations of the various processes that control the materials behavior.
Virtual Materials Design: Properties of Cellular Solids Derived from 3D Tomographic Images
Authors: Knackstedt M A. , Arns C. H. , Saadatfar M. , Senden T. J. , Sakellariou A. , Sheppard A. P. , Sok R. M. , Schrof W. , Steininger H.
Published: April 2005

Properties of cellular solids are a direct consequence of their complex microstructure. Linking properties to structure will lead to an understanding of how these materials can be engineered for given applications. Three dimensional images of a number of industrial cellular foam morphologies are experimentally acquired via micro‐CT; structural characteristics and physical properties are calculated directly on the images. Comparisons with common empirical and theoretical estimates and experimental data are encouraging.
Kinetic parameter estimation for a multiresponse nonlinear reaction model
Authors: Routray Kamalakanta , Deo Goutam
Published: April 2005

The kinetic parameters are successfully estimated for the propane oxidative dehydrogenation (ODH) reaction over vanadia–alumina catalyst under steady‐state conditions. The 5% V2O5/Al2O3 catalyst is synthesized using an incipient‐wetness impregnation technique. Characterization studies, such as surface area measurements, Raman spectroscopy, and temperature‐programmed reduction (TPR), reveal that only reducible molecularly dispersed surface vanadium oxide species are present and the Al2O3 support is not affected. Reaction data suggest that COx's (CO and CO2) are secondary products. Consequently, a single‐site consecutive Mars–van Krevelen (MVK) mechanism is chosen to explain the reaction data. This consecutive reaction mechanism explains the steady‐state reaction data obtained as a function of reaction temperature and propane to oxygen molar ratio. The kinetic parameters are estimated using a nonlinear multiresponse analysis. A determinant criterion is used as the objective function for minimization, which is achieved with a real‐coded genetic algorithm (GA). Based on a profiling technique the kinetic parameters are tested for nonlinearity and correlation between parameters. Additional use of the profiling technique is in reparameterization and obtaining maximum likelihood intervals. The application of the estimated kinetic parameters for improved understanding of the reaction, the optimum conditions of reactor operation, and catalyst design are then discussed. © 2005 American Institute of Chemical Engineers AIChE J, 2005
Design of reactive distillations for acetic acid esterification
Authors: Tang Yeong‐Tarng , Chen Yi‐Wei , Huang Hsiao‐Ping , Yu Cheng‐Ching , Hung Shih‐Bo , Lee Ming‐Jer
Published: April 2005

The reactive distillation provides an attractive alternative for reaction/separation processes with reversible reactions, especially for etherification and esterification. The discrete nature of chemical species and the complexity of phase equilibria seem to cloud the picture in understanding reactive distillation. The esterifications of acetic acid with five different alcohols, ranging from C1 to C5, are studied. First, qualitative relationships between macroscopic process flowsheet and microscopic phase equilibria are established, and the process flowsheets are classified into type I, II, and III for these five systems. Next, a systematic design procedure is devised to optimize the design, based on the total annual cost (TAC) and dominant design variables are identified for different flowsheets. Once quantitative design is available, process characteristic are analyzed and potential problems in process operation are identified. Finally, the economic potentials of these three different flowsheets are explored and explanations are given. The results clearly indicate that it is possible to systemize the design of reactive distillation by qualitatively generating flowsheet from phase equilibria and by quantitatively completing the process flow diagram from a sequential design procedure. Moreover, some of the flowsheets presented in this work cannot be found elsewhere in the open literature. © 2005 American Institute of Chemical Engineers AIChE J, 2005
Zipfian and Lotkaian continuous concentration theory
Authors: Egghe L.
Published: April 2005

In this article concentration (i.e., inequality) aspects of the functions of Zipf and of Lotka are studied. Since both functions are power laws (i.e., they are mathematically the same) it suffices to develop one concentration theory for power laws and apply it twice for the different interpretations of the laws of Zipf and Lotka. After a brief repetition of the functional relationships between Zipf's law and Lotka's law, we prove that Price's law of concentration is equivalent with Zipf's law. A major part of this article is devoted to the development of continuous concentration theory, based on Lorenz curves. The Lorenz curve for power functions is calculated and, based on this, some important concentration measures such as the ones of Gini, Theil, and the variation coefficient. Using Lorenz curves, it is shown that the concentration of a power law increases with its exponent and this result is interpreted in terms of the functions of Zipf and Lotka.
Maleimido‐Terminated Self‐Assembled Monolayers
Authors: Wang Yayun , Cai Jun , Rauscher Hubert , Behm Rolf Jürgen , Goedel Werner A.
Published: April 2005

Four approaches have been explored for the preparation of maleimido‐functionalized self‐assembled monolayers (SAMs) on silicon. SAMs prepared by self‐assembly of maleimido‐functionalized alkyltrichlorosilanes (11‐maleimido‐undecyl‐trichlorosilane) on oxide‐covered silicon yield higher signals from maleimido functionalities in ATR‐IR (attenuated total reflection IR) spectroscopy and XPS (X‐ray photoelectron spectroscopy) than the other three methods. The surface composition of maleimido groups was tailored further by the formation of mixed monolayers with nonfunctionalized alkyltrichlorosilanes (decyltrichlorosilane). The order of the alkyl chains within the monolayers only slightly depends on the composition of the mixed monolayers. We utilized the maleimido‐terminated SAMs to bind various nucleophilic compounds, alkylamines, alkylthiols, and thiol‐tagged DNA oligonucleotides by means of conjugate addition.
Self‐Assembled Structure in Room‐Temperature Ionic Liquids
Authors: Hao Jingcheng , Song Aixin , Wang Jingzheng , Chen Xiao , Zhuang Wenchang , Shi Feng , Zhou Feng , Liu Weimin
Published: April 2005

Self‐assembled vesicles, structurally equivalent to some hydrotropes, have been obtained from a Zn2+–fluorous surfactant or in the mixture of Zn2+–fluorous surfactant/zwitterionic surfactant in room‐temperature ionic liquids (RTILs). The existence of bilayers arranged in vesicles in RTILs would be very exciting, open several new possibilities as reaction media, and increase our understanding of the physical and chemical factors for self‐assembling systems in RTILs.
Topography of pig retinal ganglion cells
Authors: Garcá Mónica , Ruiz‐Ederra Javier , Hernández‐Barbáchano Henesto , Vecino Elena
Published: April 2005

In the present work we analyzed the distribution of retinal ganglion cells (RGCs) in the pig retina. RGCs were retrogradely labeled in vivo by injecting Fluoro‐Gold into the optic nerve. RGC density and the distribution of RGCs in terms of soma size were analyzed. Different regions of the porcine retina were identified following analysis of the distribution of RGCs in terms of cell density and soma size: in the central retina, we found a high‐density horizontal RGC band lying dorsal to the optic disc. Moreover, in this region, a high proportion of RCGs with small soma size was observed. From the central to the more peripheral retina, we observed a decrease in RGC density, together with a greater presence of RGCs with larger somas. The results of this study should prove to be useful as a foundation for future studies with the porcine retina as a model in ophthalmic research. The study also highlights the necessity to label the RGC population specifically with retrograde tracers in order to quantify precisely alterations in the cell population associated with experimental treatments. J. Comp. Neurol. 486:361–372, 2005. © 2005 Wiley‐Liss, Inc.
Selectivity of Asymmetric Macrocyclic Compartmental Lanthanide(III) Complexes towards Alkali and Alkaline‐Earth Metal Ions
Authors: Barge Alessandro , Botta Mauro , Casellato Umberto , Tamburini Sergio , Alessandro Vigato P.
Published: April 2005

The asymmetric macrocyclic compartmental ligand H2L, derived from the [1+1] condensation of 3,3'‐(3‐oxapentane‐1,5‐diyldioxy)bis(2‐hydroxybenzaldehyde) with 1,5‐diamine‐3‐azamethylpentane, forms the complexes [LnNa(L)(Cl)2(CH3OH)] (Ln = La–Nd, Sm–Lu) where the lanthanide(III) ion resides in the N3O2 Schiff base coordination site and thesodium ion is located in the O3O2 crown‐like cavity. The new heterodinuclear complexes [LnCa(L)(Cl)2(CH3OH)(H2O)]Cl (Ln = Tb, Dy, Tm, Yb) were prepared and characterised by single‐crystal X‐ray diffraction, IR, 1H and 13C NMR spectroscopy and their homogeneity and stoichiometry (Ln:Ca:Cl = 1:1:3 molar ratio) were ascertained by SEM‐EDS analysis. The single‐crystal X‐ray structure of [YbCa(L)(Cl2)(EtOH)(H2O)]·Cl·2H2O has been determined. The complex is monoclinic, space group P21/c, with a = 10.033(2), b = 11.702(2), c = 27.796(6) Å and β = 105.51(3)°. The ytterbium ion is seven‐coordinate within the N3O2 site and is in a pentagonal bipyramidal environment and bonded, in the axial positions, to two chloride ions. The calcium ion is seven‐coordinate within the O3O2 site and is bonded to the ethyl alcohol oxygen and to one water molecule. The significant contact between the calcium ion and the chloride ions increases the coordination number of the metal ion to eight in a square antiprismatic environment. The selectivity of the etheric site towards alkali and alkaline‐earth metal ions has been quantitatively assessed by evaluating, with 23Na NMR spectroscopy, the transmetallation reaction involving the coordinated Na+ ion in the complexes [LnNa(L)(Cl)2 (CH3OH)] (Ln = Tb, Dy, Tm and Yb) and Li+, K+ and Ca2+. The affinity constants follow the general order KCa >> KLi ≥ KK. Quantitative kinetic analyses were performed on the complex [TmNa(L)(Cl)2(CH3OH)] using variable temperature 23Na NMR spectroscopy in CD3OD. It was ascertained that the exchange rate Nabound/Nafree is independent of the presence of increasing amounts of water in the methanolic solution. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005)
An Exploration of the Structural and Bonding Variability in Mixed‐Ligand Benzimidazole‐2‐thione(bromo)(triarylphosphane)dicopper(I) Complexes with Diamond‐Shaped Cu2(μ‐X)2 Core Structures
Authors: Hadjikakou Sotiris K. , Antoniadis Constantinos D. , Aslanidis Paraskevas , Cox Philip J. , Tsipis Athanassios C.
Published: April 2005

Reaction of copper(I) bromide with benz‐1,3‐imidazole‐2‐thione (bzimtH2) in the presence of one equivalent of triphenylphosphane (PPh3), tri‐meta‐tolylphosphane (tmtp) or tri‐para‐tolylphosphane (tptp) in acetonitrile/methanol solvent afforded dinuclear complexes formulated as [CuBr(bzimtH2)(PR3)]2. The new complexes were characterized by IR, UV/Vis, and 1H NMR spectroscopy, while the crystal structures of [{CuBr(μ2‐S‐bzimtH2)(PPh3)}2]0.78[{Cu(μ2‐Br)(PPh3)(bzimtH2)}2]0.22 (1), [CuBr(μ2‐S‐bzimtH2)(tmtp)]2 (2) and [CuBr(μ2‐S‐bzimtH2)(tptp)]2 (3) were determined by single‐crystal X‐ray diffraction methods. In complex 1, with spectator PPh3 ligands, the unit cell of the crystal consists of two different half‐molecules, both corresponding to the formula [CuBr(bzimtH2)(PPh3)]2. One of the two molecules (molecule A) is a symmetrical dicopper(I) complex in which the exocyclic thione S‐atoms serve as bridges between the CuI ions. The second one (molecule B) is disordered and can be resolved into two separate entities, one μ2‐S dicopper(I) complex, similar to molecule A (molecule B1), and another one (molecule B2) involving μ2‐Br bridges. In contrast, in complexes 2 and 3, with spectator tmtp and tptp ligands, only the bzimtH2‐bridged dicopper complexes are formed. Density functional calculations at the B3LYP level of theory provided a satisfactory description of the structural, bonding, electronic and related properties of all dicopper complexes exhibiting the “diamond‐shaped” Cu2(μ‐X)2 (X = S or Br) core structures and account well for their structural preferences. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005)
Reactivity of Lewis Acid/Base Stabilized Phosphanyl‐ and Arsanylboranes towards a Platinum(0) Complex
Authors: Vogel Ulf , Schwan Karl‐Christian , Hoemensch Petra , Scheer Manfred
Published: April 2005

The Lewis acid/base stabilized phosphanylboranes and ‐arsanes [(CO)5W(H2EBH2·NMe3)] (1a: E = P; 1b: E = As) have been shown to react with the platinum(0) complex [(Ph3P)2Pt(C2H4)] under oxidative addition of the E–H bond to the platinum center. The complexes cis‐[(Ph3P)2Pt(H)(μ‐EHBH2·NMe3)W(CO)5] (2a: E = P; 2b: E = As) are formed. Complex 2a is unstable in solution at room temperature and slowly reacts with loss of carbon monoxide to form [(Ph3P)2Pt(μ‐H)(μ‐EHBH2·NMe3)W(CO)4] (3a: E = P). An analogous complex 3b (E = As) is formed from 2b only by refluxing in CH2Cl2. The reaction of 2a to 3a can be reversed by addition of CO, whereas the arsenic compound 3b does not show this reactivity pattern. All new compounds have been comprehensively characterized by spectroscopy and X‐ray crystallography. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005)
Intramolecular “CH···π(Metal Chelate Ring) Interactions” as Structural Evidence for Metalloaromaticity in Bis(pyridine‐2,6‐diimine)RuII Complexes
Authors: Jiang Yan‐feng , Xi Chan‐juan , Liu Yu‐zhou , Niclós‐Gutiérrez Juan , Choquesillo‐Lazarte Duane
Published: April 2005

The synthesis and structural characterization of two novel RuII complexes (1 and 2) with tridentate pyridine‐2,6‐diimine ligands are described. In both compounds, ortho‐CH bonds from the phenyl or phenyl‐like rings produce unexpected CH···π interactions with ruthenium‐α,α'‐diimine chelate rings. This insight is thought to provide new structural evidence for the metalloaromaticity of the chelate rings in the ruthenium complexes studied. The molecular geometry of complex 1 is remarkably similar to S4 symmetrical geometry, which is also a consequence of the four CH···π(chelate ring) interactions working cooperatively. In contrast, there are only two pairs of these interactions working in complex 2 because of the steric effects and electronic influences caused by the methyl‐group substitutions. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005)
Synthesis and Characterization of Magnesium‐Aluminum Layered Double Hydroxides Containing (Tetrasulfonated porphyrin)cobalt
Authors: Barbosa César A. S. , Ferreira Ana Maria D. C. , Constantino Vera R. L.
Published: April 2005

We report the synthesis and characterization of a magnesium‐aluminum layered double hydroxide (LDH) containing[5,10,15,20‐tetrakis(4‐sulfonatophenyl)porphyrinato]cobalt(II)(CoTPhsP) by two routes: (i) CoTPhsP intercalation by structure reconstruction of the calcined pristine LDH [Mg2.8Al(CoTPhsP)int] and (ii) adsorption of the CoTPhsP on the external surfaces of the noncalcined pristine LDH [Mg3.0Al(CoTPhsP)ads]. The intercalation and adsorption of CoTPhsP in the LDHs were evaluated using different techniques, such as X‐ray diffraction, thermogravimetry, scanning electronic microscopy, and surface area and porosity analysis. Further characterization by electron spin resonance and UV/Vis spectroscopy showed that the CoTPhsP molecules adsorbed and intercalated in the LDHs are present as two predominant species: the complex formed with molecular oxygen (CoTPhsP–O2) and the corresponding deoxy monomeric species (CoTPhsP). The stability and reactivity of the CoTPhsP immobilized in the LDHs were evaluated in the presence of hydrogen peroxide solution. CoTPhsP in homogeneous conditions is deactivated by molecular aggregation and/or oxidative self‐destruction in the presence of H2O2. On the other hand, CoTPhsP stability and reactivity were improved when adsorbed and intercalated in the LDHs. Mg3.0Al(CoTPhsP)ads is more active than Mg2.8Al(CoTPhsP)int in the decomposition of hydrogen peroxide to H2O and O2. A porosity analysis carried out by N2 adsorption‐desorption experiments for the intercalated material exhibited a type‐IV isotherm characteristic of nonmicroporous materials. Hence, the CoTPhsP molecules located in the LDH galleries are not acessible to the H2O2, while the metal centers in the Mg3.0Al(CoTPhsP)ads sample are more available, which may explain the enhanced reactivity. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005)
Chiral Indenes and Group‐4 Metallocene Dichlorides Containing α‐ and β‐Pinenyl‐Derived Ligand Substituents: Synthesis and Catalytic Applications in Polymerization and Carboalumination Reactions
Authors: Silver Satu , Puranen Arto , Sjöholm Rainer , Repo Timo , Leino Reko
Published: April 2005

The synthesis and characterization of chiral bis(indenyl)zirconium dichlorides containing β‐pinenyl‐derived ligand substituents is reported. Unbridged metallocene complexeshaving the {[(1S,2S,5S)‐6,6‐dimethylbicyclo[3.1.1]hept‐2‐yl]methyl}dimethylsilyl substituent in both 1‐ and 2‐positions of the indenyl moiety were prepared and isolated in moderate to low yields by reaction of the corresponding indenyllithium salts with ZrCl4 followed by work‐up and crystallization procedures. The corresponding tetrahydroindenyl complexes were obtained in excellent yields by catalytic hydrogenation of the indenyl six‐membered rings. In a complementary approach, a synthetic route to α‐pinenyl‐substituted indenyl ligand analogues was briefly evaluated, which however, suffered from low yields. Selected β‐pinenyl‐substituted indenyl complexes were scanned as catalysts for the dehydropolymerization of phenylsilane upon activation with nBuLi, for polymerization of ethylene and propylene upon activation with methylaluminoxane (MAO) as well as for enantioselective carboalumination of 1‐octene with triethyl‐ and trimethylaluminum. The bis(indenyl) complexes catalyzed the carboalumination reaction, albeit only low yields (8–16 %) and low enantioselectivities (ee = 0.5–10 %) were obtained. The 2‐substituted bis(indenyl)zirconocene/MAO catalyst system produced atactic low‐molecular weight polypropylene with low polymerization activity whereas both 1‐ and 2‐substituted complexes showed high activities in ethylene polymerization producing polyethylenes with high molecular weights (Mw > 440000). (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005)
The First Sandwich‐Type Heteropolytungstates Consisting of Trivacant Gallium(III)‐Substituted Keggin Fragments
Authors: Drewes Daniel , Limanski Eva Melanie , Krebs Bernt
Published: April 2005

The new polyoxotungstates (NH4)5Na9[Cu4(H2O)2(GaW9O34)2]·22 H2O (1) and (NH4)14[Zn4(H2O)2(GaW9O34)2]·37 H2O (2) were synthesized in aqueous solution and characterized by IR and Raman spectroscopy, energy dispersive X‐ray fluorescence and single‐crystal X‐ray analysis. Compounds 1 and 2 contain the trivacant α‐B‐(GaW9O34)11– Keggin fragment, which is structurally characterized for the first time. The lacunary (GaW9O34)11– structure exhibits a centered GaIII atom, which is bound to four oxygen atoms and thus achieves a tetrahedral coordination sphere. The synthesis of 1–2 enlarges the class of sandwich‐type polyoxoanions and enables the syntheses of a new series of gallium(III)‐substituted polyoxotungstates. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005)
Prevalence of five previously reported and recurrent BRCA1 genetic rearrangement mutations in 20,000 patients from hereditary breast/ovarian cancer families
Authors: Hendrickson Brant C. , Judkins Thaddeus , Ward Benjamin D. , Eliason Kristilyn , Deffenbaugh Amie E. , Burbidge Lynn Anne , Pyne Kristin , Leclair Benoît , Ward Brian E. , Scholl Thomas
Published: April 2005

Many rearrangement mutations in the BRCA1 gene have been identified. It is becoming clear that some of these mutations are prevalent, and therefore their detection is necessary in order for clinical genetic tests to have high sensitivity. Published information on particular rearrangements is frequently limited to a single patient, small groups of patients, or patients of a particular ethnicity. The objectives of this work included characterizing the prevalence of five specific rearrangement mutations in a large North American patient population. A mutation‐specific multiplex PCR assay was used for determining the prevalence of five BRCA1 rearrangement mutations that previously had been reported to occur in unrelated patients. The mutation status of these rearrangements, which came from 20,712 patients at high risk for hereditary breast and/or ovarian cancers who had submitted specimens for clinical genetic testing, is presented. The results, obtained from 2,634 mutation carriers, showed a 6‐kb duplication of exon 13, identified in 53 patients (2.01%); a 26‐kb deletion encompassing exons 14–20, detected in seven patients (0.27%); a 510‐bp deletion of exon 22, detected in 5 patients (0.19%); and a 3.4‐kb deletion of exon 13, detected in one patient (0.04%). A previously reported 7.1‐kb deletion of exons 8–9 was not found. The high frequency of the exon 13 duplication makes it the fourth most prevalent mutation in these patients. These results provide an accurate picture of the prevalence of these mutations in hereditary breast/ovarian cancer patients undergoing genetic testing in North America. © 2005 Wiley‐Liss, Inc.
Alterations in metabolism and gap junction expression may determine the role of astrocytes as “good samaritans” or executioners
Authors: Farahani Reza , Pina‐Benabou Mara H. , Kyrozis Andreas , Siddiq Ayesha , Barradas Penha C. , Chiu Fung‐Chow , Cavalcante Leny A. , Lai James C.K. , Stanton Patric K. , Rozental Renato
Published: April 2005

Our knowledge of astroglia and their physiological and pathophysiological role(s) in the central nervous system (CNS) has grown during the past decade, revealing a complex picture. It is becoming increasingly clear that glia play a significant role in the homeostasis and function of the CNS and that neurons should no longer be considered the only cell type that responds, both rapidly and slowly, to electrochemical activity. We discuss recent advances in the field with an emphasis on the impact of hypoxia and ischemia on astrocytic metabolism and the functional relationship between glucose metabolism and gap junctions in astrocytes. We also address the controversy over whether astrocytic gap junctions mediate protection or killing of neurons during or after hypoxic or ischemic insults. © 2005 Wiley‐Liss, Inc.
Automated quality assurance routines for fMRI data applied to a multicenter study
Authors: Stöcker Tony , Schneider Frank , Klein Martina , Habel Ute , Kellermann Thilo , Zilles Karl , Shah N. Jon
Published: April 2005

Standard procedures to achieve quality assessment (QA) of functional magnetic resonance imaging (fMRI) data are of great importance. A standardized and fully automated procedure for QA is presented that allows for classification of data quality and the detection of artifacts by inspecting temporal variations. The application of the procedure on phantom measurements was used to check scanner and stimulation hardware performance. In vivo imaging data were checked efficiently for artifacts within the standard fMRI post‐processing procedure by realignment. Standardized and routinely carried out QA is essential for extensive data amounts as collected in fMRI, especially in multicenter studies. Furthermore, for the comparison of two different groups, it is important to ensure that data quality is approximately equal to avoid possible misinterpretations. This is shown by example, and criteria to quantify differences of data quality between two groups are defined. Hum Brain Mapp 25:237–246, 2005. © 2005 Wiley‐Liss, Inc.
Differential activity in left inferior frontal gyrus for pseudowords and real words: An event‐related fMRI study on auditory lexical decision
Authors: Xiao Zhuangwei , Zhang John X. , Wang Xiaoyi , Wu Renhua , Hu Xiaoping , Weng Xuchu , Tan Li Hai
Published: April 2005

After Newman and Twieg ([2001]: Hum Brain Mapp 14:39–47) and others, we used a fast event‐related functional magnetic resonance imaging (fMRI) design and contrasted the lexical processing of pseudowords and real words. Participants carried out an auditory lexical decision task on a list of randomly intermixed real and pseudo Chinese two‐character (or two‐syllable) words. The pseudowords were constructed by recombining constituent characters of the real words to control for sublexical code properties. Processing of pseudowords and real words activated a highly comparable network of brain regions, including bilateral inferior frontal gyrus, superior, middle temporal gyrus, calcarine and lingual gyrus, and left supramarginal gyrus. Mirroring a behavioral lexical effect, left inferior frontal gyrus (IFG) was significantly more activated for pseudowords than for real words. This result disconfirms a popular view that this area plays a role in grapheme‐to‐phoneme conversion, as such a conversion process was unnecessary in our task with auditory stimulus presentation. An alternative view was supported that attributes increased activity in left IFG for pseudowords to general processes in decision making, specifically in making positive versus negative responses. Activation in left supramarginal gyrus was of a much larger volume for real words than for pseudowords, suggesting a role of this region in the representation of phonological or semantic information for two‐character Chinese words at the lexical level. Hum Brain Mapp 25:212–221, 2005. © 2005 Wiley‐Liss, Inc.
Brain activity associated with painfully hot stimuli applied to the upper limb: A meta‐analysis
Authors: Farrell Michael J. , Laird Angela R. , Egan Gary F.
Published: April 2005

The capacity of pain to alert against potential injury or focus attention on damaged tissue is enhanced by the intrinsically aversive nature of the experience. Finding methods to relieve pain will ultimately be facilitated by deeper understanding of the processes that contribute to the experience, and functional brain imaging has contributed substantially toward that end. An impressive body of literature has identified a distributed network of pain‐related activity in the brain that is subject to considerable modulation by different stimulus parameters, contextual factors, and clinical conditions. The fundamental substrates of the pain network are yet to be distilled from the highly variable results of studies published thus far. Qualitative reviews of the pain‐imaging literature have been contributory, but lack the greater surety of quantitative methods. We employ the activation likelihood estimation (ALE) meta‐analytic technique to establish the most consistent activations among studies reporting brain responses subsequent to the application of noxious heat. A network of pain‐related activity was replicated for stimuli to either upper limb that included two discernible regions of the mid‐anterior cingulate cortex, bilateral thalami, insula, and opercula cortices, posterior parietal cortex, premotor cortex, supplementary motor area, and cerebellum. The findings of the meta‐analysis resonate with other streams of information that continue to enhance our understanding of pain in the brain. The results also point toward new areas of research that may be fruitful for the exploration of central pain processing. Hum Brain Mapp 25:129–139, 2005. © 2005 Wiley‐Liss, Inc.