bluuebunny/crossref_metadata_2025 huggingface dataset:
Semiquantitative evaluation of fibronectin adsorption on unmodified and sulfonated polystyrene, as related to cell adhesion
Authors: Kowalczyńska Hanna M. , Nowak‐Wyrzykowska Małgorzata , Kołos Robert , Dobkowski Jacek , Kamiński Jarosław
Published: January 2008

The process of human fibronectin (FN) adsorption on nonsulfonated and sulfonated polystyrene surfaces was studied in relation to mechanisms of L1210 cell adhesion. Radioisotope assays directed towards FN, as well as ELISA measurements of adsorbed FN and bovine serum albumin (BSA) were carried out. 125I radioisotope assays led to linear FN adsorption isotherms. When combined to ELISA measurements for FN, they revealed the multilayer adsorption. Results indicated a large difference in the saturating first‐layer surface density of FN adsorbed on sulfonated and nonsulfonated polystyrene surfaces: significantly (ca. factor of 5) less FN molecules are necessary to complete a monolayer on sulfonated than on nonsulfonated polystyrene. This suggests an unfolded conformation of FN on sulfonated polystyrene, and a more compact one on the nonsulfonated polymer. Significant conformational changes of FN are also indicated by the following: (1) early phase of cell adhesion to FN adsorbed on sulfonated polystyrene surfaces is significantly (ca. factor of 6) higher than to FN on nonsulfonated surfaces, and in the former case adhesion proceeds mostly via α5β1 integrins; (2) RGD, the crucial fragment within central cell binding domain, seems to be partially hidden in the protein structure adopted on nonsulfonated surfaces; (3) patterns of F‐actin organization differ in cells adhering to FN on sulfonated and nonsulfonated surfaces. The ELISA study directed against BSA (this protein always present on the surface after the adsorption of FN), showed the importance of “free area,” uncovered by both proteins, which influence the cell adhesion processes. © 2008 Wiley Periodicals, Inc. J Biomed Mater Res, 2008
A phase I clinical trial of interferon‐beta gene therapy for high‐grade glioma: novel findings from gene expression profiling and autopsy
Authors: Wakabayashi Toshihiko , Natsume Atsushi , Hashizume Yoshio , Fujii Masazumi , Mizuno Masaaki , Yoshida Jun
Published: January 2008

Background

High‐grade gliomas are highly lethal neoplasms representing approximately 20% of all intracranial tumors. Cationic liposome‐mediated interferon‐beta (IFN‐β) gene transfer has been found to induce regression of experimental glioma. We have previously performed a pilot clinical trial to evaluate the safety and effectiveness of this IFN‐β gene therapy in five patients with high‐grade glioma. Two patients showed more than 50% reduction while others had stable disease 10 weeks after treatment initiation.

Methods

To identify alterations in gene expression in brain tumors 2 weeks after the gene therapy trial, we used a microarray technology and Gene Ontology analysis. The results were validated by patients' clinical course and findings of histology and autopsy.

Results and conclusions

Using hierarchical clustering and principal component analysis, five series of gene therapy trials were classified according to the response to IFN‐β gene therapy. Significant changes in gene expression related to immunoresponse and apoptosis were observed. Moreover, novel patterns of altered gene expression, such as inhibition of neovascularization, were identified, suggesting the involvement of pathways reported previously as not involved. Autopsy and histological examinations revealed dramatic changes in the tumor tissues after therapy in all patients. Many tumor cells showed necrotic changes, and immunohistochemistry identified numerous CD8‐positive lymphocytes and macrophages infiltrating the tumor and surrounding tissues; these were probably the effects of therapy. Simultaneously, CD34‐immunoreactive vessels were notably decreased in the vector‐injected brain. This study facilitates the understanding of the antitumor mechanism and helps identify candidate target molecules for new approaches. However, additional clinical trials are warranted. Copyright © 2008 John Wiley & Sons, Ltd.
Coating of adeno‐associated virus with reactive polymers can ablate virus tropism, enable retargeting and provide resistance to neutralising antisera
Authors: Carlisle Robert C. , Benjamin Reuben , Briggs Simon S. , Sumner‐Jones Stephanie , McIntosh Jenny , Gill Deborah , Hyde Steve , Nathwani Amit , Subr Vladimir , Ulbrich Karel , Seymour Leonard W. , Fisher Kerry D.
Published: January 2008

Background

Copolymers based on poly‐[N‐(2‐hydroxypropyl) methacrylamide] (HPMA) have been used previously to enable targeted delivery of adenovirus. Here we demonstrate polymer‐coating techniques can also be used to modify and retarget adeno‐associated virus (AAV) types 5 and 8.

Methods

Three strategies for modifying transductional targeting of AAV were employed. The first involved direct reaction of AAV5 or AAV8 with amino‐reactive HPMA copolymer. The second approach used carbodiimide (EDC) chemistry to increase the number of surface amino groups on the AAV5 capsid, thereby improving coating efficiency. In the third approach, the AAV5 genome was isolated from capsid proteins and delivered in a synthetic polyplex consisting of polyethylenimine (PEI) and HPMA.

Results

Efficient covalent attachment of HPMA copolymer to AAV5 could only be achieved following modification of the virus with EDC. Coating inhibited sialic acid dependent infection and provided a platform for retargeting via new ligands, including basic fibroblast growth factor. Retargeted infection was shown to be partially resistant to neutralising antisera. Delivery of AAV5 genomes using PEI and HPMA was efficient and provided absolute control of tropism and protection from antisera. In contrast AAV8 could be reacted directly with HPMA copolymer and allowed specific retargeting via the epidermal growth factor receptor, but gave no protection against neutralising antisera.

Conclusions

Reactive HPMA polymers can be used to ablate the natural tropism of both AAV8 and EDC‐modified AAV5 and enable receptor‐specific infection by incorporation of targeting ligands. These data show transductional targeting strategies can be used to improve the versatility of AAV vectors. Copyright © 2008 John Wiley & Sons, Ltd.
The SST‐forced predictability of the sub‐seasonal mode over East Asia with an atmospheric general circulation model
Authors: Kim Ki‐Young , Kitoh Akio , Ha Kyung‐Ja
Published: January 2008

The sea surface temperature (SST)‐forced predictability in precipitation is investigated in terms of the seasonal mean modes (SMMs) for June–July (JJ) and the sub‐seasonal mode (SSM) using the 24‐year six‐member ensembles simulation with an atmospheric general circulation model (AGCM). The SSM was defined as a 20‐day window length by an extended empirical orthogonal function (EOF) over the East Asian monsoon region. For the JJ mean rainfall, the first EOF of the model ensemble is considered to be the forced SST mode, with being an El Niño Southern Oscillation (ENSO) related pattern from the regressed SST field. The first mode of model was well correlated with the second mode of the observation in the spatial and temporal variation.

In the potential predictability, the analysis of variance (ANOVA) was used for the mean mode and the SSM. The potential predictability for the SMM is improved over the north of the 30°N. Compared with JJ mean mode, the SSM has more SST‐forced variance and less internal variability. Copyright © 2008 Royal Meteorological Society
Optical THz‐wave generation with periodically‐inverted GaAs
Authors: Vodopyanov K.L.
Published: January 2008

We overview methods of THz‐wave generation using frequency down‐conversion in GaAs with periodically‐inverted crystalline orientation. First, we compare different nonlinear‐optical materials suitable for THz generation, analyze THz generation process in quasi‐phase‐matched crystals and consider theoretical limits of optical‐to‐THz conversion. Then, we review single‐pass optical rectification experiments with femtosecond pump pulses, performed in periodically‐inverted GaAs, where monochromatic THz output tunable in the range 0.9–3 THz was produced. Finally, we describe a novel approach to create a compact highly efficient tunable (0.5–3.5 THz) room temperature monochromatic THz source, based on the concept of intracavity THz generation via resonantly‐enhanced difference frequency mixing. This approach allowed generating of 1 mW of average THz power, potentially scalable to 10–100 mW.
Modelling human hip joint lubrication subject to walking cycle
Authors: Meziane A. , Bou‐Saïd B. , Tichy John
Published: January 2008

This paper deals with the study of a hip joint prosthesis subject to a walking cycle. Human joints are lubricated by synovial fluid (SF). To properly model joint performance, one must take into account the behaviour of this fluid, which is highly viscoelastic as confirmed in early experimental work. The Phan‐Thien and Tanner (PTT) model is one of the most widely used rheological models. It can properly describe the common characteristics of viscoelastic non‐Newtonian fluids. Based on a microstructural description of the fluid, it is possible to establish laws of rheological behaviour to reproduce shock or the sudden inception of shear, taking into account large deformation and viscoelastic effects. Modelling the geometry of the total hip replacement, the PTT model is applied in spherical coordinates to a thin confined fluid film. Using a modified Reynolds equation developed for this specific geometry, we present a numerical simulation of an artificial hip joint subject to a walking cycle. The equilibrium position depends on the load magnitude and also depends strongly on the load direction. The non‐linear response of the SF leads to some unanticipated complexities. In our case, the dominant effect is the squeeze action between the surfaces. The contact behaviour depends not only on the geometry and kinematics but also on the fluid properties. The minimum film thickness remains higher than likely roughness height during these ‘normal’ conditions. When considering the design of hip joint prostheses, attention should be paid to the rheological properties of SF. Copyright © 2008 John Wiley & Sons, Ltd.
Macromol. Rapid Commun. 3/2008
Authors: Schwalm Thorsten , Rehahn Matthias
Published: January 2008

Cover: Poly(p‐phenylene vinylenes) (PPVs) are very useful materials for optoelectronic devices, and the Gilch reaction offers powerful access to these intensely colored polymers. However, minimizing intrinsic defects and tailoring the molar masses are still difficult tasks. The cover picture underlines that oxygen acts very efficiently as a retarder and regulator in this functional polymer synthesis. Further details can be found in the article by T. Schwalm and M. Rehahn* on page 207.
Stimulation of sister chromatid exchanges and mutation by aflatoxin B1‐DNA adducts in Saccharomyces cerevisiae requires MEC1 (ATR), RAD53, and DUN1
Authors: Fasullo Michael , Sun Mingzeng , Egner Patricia
Published: January 2008

The hepatocarcinogen aflatoxin B1 (AFB1) is a potent recombinagen but weak mutagen in the yeast Saccharomyces cerevisiae. AFB1 exposure induces DNA damage‐inducible genes, such as RAD51 and those encoding ribonucleotide reductase (RNR), through a MEC1 (ATR homolog)‐dependent pathway. Previous studies have indicated that MEC1 is required for both AFB1‐associated recombination and mutation, and suggested that AFB1‐DNA adducts are common substrates for recombination and mutagenesis. However, little is known about the downstream effectors of MEC1 required for genotoxic events associated with AFB1 exposure. Here we show that AFB1 exposure increases frequencies of RAD51‐dependent unequal sister chromatid exchange (SCE) and activates Rad53 (CHK2). We found that MEC1, RAD53, and DUN1 are required for both AFB1‐associated mutation and SCE. Deletion of SML1, which encodes an inhibitor of RNR, did not suppress the DUN1‐dependent requirement for AFB1‐associated genetic events, indicating that higher dNTP levels could not suppress the dun1 phenotype. We identified AFB1‐DNA adducts and show that approximately the same number of adducts are obtained in both wild type and rad53 mutants. Since DUN1 is not required for UV‐associated mutation and recombination, these studies define a distinct role for DUN1 in AFB1‐associated mutagenesis and recombination. We speculate that AFB1‐associated DNA adducts stall DNA replication, a consequence of which can either be mutation or recombination. © 2008 Wiley‐Liss, Inc.
HSQC pulse sequences for 19F
Authors: Adams Bruce
Published: January 2008

Heteronuclear single quantum coherence (HSQC) sequences using adiabatic (or composite) 180° pulses, suitable for applications requiring wide spectral widths in F2, are described. The sequences can be used with or without multiplicity editing. One variant will work even in the presence of homonuclear couplings that are equal to the heteronuclear 1‐bond coupling. Copyright © 2008 John Wiley & Sons, Ltd.
Simulation of Polymerization and Long Chain Branch Formation in a Semi‐Batch Reactor Using Two Single‐Site Catalysts
Authors: Mehdiabadi Saeid , Soares João B. P. , Dekmezian Armenag H.
Published: January 2008

We developed a mathematical model for the solution polymerization of olefins in a semi‐batch reactor with two single‐site catalysts. In the propylene polymerization case, our objective is to study the production of a thermoplastic elastomer using two catalysts, one capable of forming isotactic chains containing terminal vinyl bonds (macromonomers) and the other producing atactic chains while also being able to copolymerize macromonomers to form long chain branches. A similar thermoplastic elastomer can be produced by polymerizing ethylene and α‐olefin comonomers when the α‐olefin reactivity ratios of the two catalysts are significantly different.

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High Solids Content Waterborne Acrylic/Montmorillonite Nanocomposites by Miniemulsion Polymerization
Authors: Diaconu Gabriela , Paulis Maria , Leiza Jose R.
Published: January 2008

Waterborne polymer/clay nanocomposites of methyl methacrylate and butyl acrylate have been prepared by miniemulsion polymerization. Two different commercial organically modified clays have been used: Cloisite 15A and Cloisite 30B. Nanocomposites with partially exfoliated structure, observed by wide‐angle X‐ray diffraction (WAXD), small angle X‐ray scattering (SAXS) and transmission electron microscopy (TEM) were obtained by batch miniemulsion polymerization with 2–4 wt.‐% clay and 30% solids content. The mechanical, thermal and permeation properties of the nanocomposites showed a substantial improvement. Furthermore, this approach has allowed the production of stable and coagulum free latex with solids content up to 42 wt.‐% with partially exfoliated structures.

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VASO‐based calculations of CBV change: Accounting for the dynamic CSF volume
Authors: Scouten A. , Constable R.T.
Published: January 2008

The goal of the vascular space occupancy (VASO) imaging technique is to use selective nulling of the blood signal to infer relative changes in cerebral blood volume (CBV). In accordance with recent work, we show that changes in the local CSF fraction (xc) with activation can significantly impact the VASO signal, thereby limiting our ability to infer ΔCBV from ΔVASO alone. Here we calculate CBV change using a VASO‐based method which ACcounts for the Dynamic Cerebrospinal (ACDC) fluid fraction. By combining data from two separate VASO acquisitions that eliminate either the blood signal (VASOb) or the CSF signal (VASOc), a nonlinear least‐squares optimization may then be used to simultaneously solve for the relative changes in CBV and CSF with activation. The method is applied across the whole brain during a breath‐holding task, offering insight into the relationship between changes in CBV and xc associated with global vasodilatation. Calculations of mean changes in CBV in different volumes of interest obtained from the proposed method compare much better with previous (gold‐standard) PET data than traditional VASO methods that do not account for a nonzero Δxc with activation. This confirms the necessity of incorporating the dynamic CSF volume into VASO‐based calculations of ΔCBV. Magn Reson Med 58:308–315, 2008. © 2008 Wiley‐Liss, Inc.
Noninvasive assessment of myocardial viability in a small animal model: Comparison of MRI, SPECT, and PET
Authors: Thomas Daniel , Bal Harshali , Arkles Jeffrey , Horowitz James , Araujo Luis , Acton Paul D. , Ferrari Victor A.
Published: January 2008

Acute myocardial infarction (AMI) research relies increasingly on small animal models and noninvasive imaging methods such as MRI, single‐photon emission computed tomography (SPECT), and positron emission tomography (PET). However, a direct comparison among these techniques for characterization of perfusion, viability, and infarct size is lacking. Rats were studied within 18–24 hr post AMI by MRI (4.7 T) and subsequently (40–48 hr post AMI) by SPECT (99Tc‐MIBI) and micro‐PET (18FDG). A necrosis‐specific MRI contrast agent was used to detect AMI, and a fast low angle shot (FLASH) sequence was used to acquire late enhancement and functional images contemporaneously. Infarcted regions showed late enhancement, whereas corresponding radionuclide images had reduced tracer uptake. MRI most accurately depicted AMI, showing the closest correlation and agreement with triphenyl tetrazolium chloride (TTC), followed by SPECT and PET. In some animals a mismatch of reduced uptake in normal myocardium and relatively increased 18FDG uptake in the infarct border zone precluded conventional quantitative analysis. We performed the first quantitative comparison of MRI, PET, and SPECT for reperfused AMI imaging in a small animal model. MRI was superior to the other modalities, due to its greater spatial resolution and ability to detect necrotic myocardium directly. The observed 18FDG mismatch likely represents variable metabolic conditions between stunned myocardium in the infarct border zone and normal myocardium and supports the use of a standardized glucose load or glucose clamp technique for PET imaging of reperfused AMI in small animals. Magn Reson Med 59:252–259, 2008. © 2008 Wiley‐Liss, Inc.
Incorporating the effects of transcytolemmal water exchange in a reference region model for DCE‐MRI analysis: Theory, simulations, and experimental results
Authors: Yankeelov Thomas E. , Luci Jeffrey J. , DeBusk Laura M. , Lin P. Charles , Gore John C.
Published: January 2008

Models have been developed for the analysis of dynamic contrast‐enhanced MRI (DCE‐MRI) data that do not require direct measurements of the arterial input function; such methods are referred to as reference region models. These models typically return estimates of the volume transfer constant (Ktrans) and the extravascular extracellular volume fraction (ve). To date such models have assumed a linear relationship between the measured R1 (≡1/T1) and the concentration of contrast agent, a transformation referred to as the fast exchange limit, but this assumption is not valid for all concentrations of an agent. A theory for DCE‐MRI reference region models which accounts for water exchange is presented, evaluated in simulations, and applied in tumor‐bearing mice. Using reasonable parameter values, simulations show that the assumption of fast exchange can underestimate Ktrans and ve by up to 82% and 46%, respectively. By analyzing a large region of interest and a single voxel the new model can return parameters within approximately ±10% and ±25%, respectively, of their true values. Analysis of experimental data shows that the new approach returns Ktrans and ve values that are up to 90% and 73%, respectively, greater than conventional fast exchange analyses. Magn Reson Med 59:326–335, 2008. © 2008 Wiley‐Liss, Inc.
Sensitivity to change of the Rheumatoid Arthritis Self‐Efficacy scale (RASE) and predictors of change in self‐efficacy
Authors: Hewlett Sarah , Cockshott Zoë , Almeida Celia , Richards Pam , Lowe Rob , Greenwood Rosemary , Kirwan John
Published: January 2008

Objectives: Patient education in rheumatoid arthritis (RA) aims to improve health outcomes by prompting people to adopt self‐management behaviours. One precursor for initiating behaviour change is self‐efficacy (SE), a belief that you can do a task. This study tested the sensitivity to change of a new scale to measure SE for self‐management in people with RA, the Rheumatoid Arthritis Self‐Efficacy scale (RASE). Exploratory analysis examined potential predictors of change in SE.

Methods: People with RA at 11 rheumatology centres, who had accepted an education programme as part of clinical care, completed questionnaires at baseline, and two and eight weeks after their programme end. Programmes were not standardized, as this was a pragmatic study in clinical practice.

Results: A total of 128 patients participated. After controlling for baseline scores, the RASE showed small but significant improvements in SE from baseline (RASE 107.57, CI 105.42‐109.72) to two weeks after programme end (RASE 110.80, CI 108.60‐112.99), and eight weeks (RASE 110.62, CI 108.40‐112.85, p < 0.001). Standardized response means, calculated both by absolute and percentage change, were 0.339 and 0.371 at two weeks after programme end, and 0.321 and 0.352 at eight weeks. Changes in the RASE were associated with behaviour initiation at two and eight weeks (r = 0.419, r = 0.342, p < 0.001). No substantial predictors of change in SE could be identified.

Conclusions: The RASE is sensitive to change in a cohort of people with RA in the UK receiving education programmes as routine clinical care. Exploratory analysis did not identify clinical or psychological factors that predict change in SE, suggesting that programmes should not be restricted to particular patients. Copyright © 2008 John Wiley & Sons, Ltd.
Thermally stable and organosoluble binaphthylene‐based poly(urea‐ether‐imide)s: one‐pot preparation and characterization
Authors: Behniafar Hossein , Haghighat Sara
Published: January 2008

A new family of wholly aromatic poly(urea‐ether‐imide)s (4a–4f) possessing binaphthylene‐twisted rings was prepared by diphenyl azidophosphate (DPAP)‐activated one‐pot polyaddition reaction of a preformed imide heterocyclic ring‐containing dicarboxylic acid, 2,2′‐bis(4‐trimellitimidophenoxy)‐ 1,1′‐binaphthyl (1) with various kinds of aromatic diamines (3a–3f). At first, with due attention to structural similarity and to compare the characterization data, a model compound 2 was synthesized by the reaction of diimide‐dicarboxylic acid 1 with two mole equivalents of aniline. In this direct method, the polymers were prepared by polyaddition reactions of the in situ‐formed diisocyanate with the aromatic diamines. Molecular weights of the poly(urea‐ether‐imide)s obtained were evaluated viscometrically, and the inherent viscosities (ηinh) measured were in the range 0.10– 0.25 dl/g. All of the polymers were characterized by FT‐IR spectroscopic method and elemental analysis. All of the resulting polymers exhibited an excellent solubility in common polar solvents such as N‐methyl‐2‐pyrrolidone (NMP), dimethyl sulfoxide (DMSO), N,N‐dimethylformamide (DMF), and N,N‐dimethylacetamide (DMAc). Crystallinity of the resulted polymers was evaluated by wide‐angle X‐ray diffraction (WXRD) method, and they exhibited nearly a non‐crystalline nature as evidenced by their diffractograms. The glass transition temperatures (Tg) of the polymers determined by differential scanning calorimetry (DSC) thermograms were in the range of 274–302°C. The temperatures at 10% weight loss (Td10%) from their thermogravimetric analysis (TGA/DTG) curves were found to be in the range of 389–414°C in nitrogen atmosphere. Copyright © 2008 John Wiley & Sons, Ltd.
Gadodiamide contrast agent ‘activates’ fibroblasts: a possible cause of nephrogenic systemic fibrosis
Authors: Edward M , Quinn JA , Mukherjee S , Jensen M‐BV , Jardine AG , Mark PB , Burden AD
Published: January 2008

Nephrogenic systemic fibrosis (NSF) is a fibrotic disease generating intense interest due to its recent discovery, and unknown cause. It appears confined to patients with renal disease and presents as grossly thickened, indurated, tight skin that is woody to palpation. Histologically, the dermis contains thickened collagen bundles, numerous plump fibroblast‐like cells, and elevated hyaluronan expression. Recent data suggest a link between the use of gadolinium chelate as an MRI contrast agent and the onset of the disease. Fibroblasts from the lesions of six NSF patients, all of whom were exposed to gadodiamide, were compared with control fibroblasts for hyaluronan and collagen synthesis. Serum from NSF patients was assessed for fibroblast hyaluronan‐stimulating activity, collagen synthesis, and gadodiamide for its effect on fibroblast proliferation and matrix synthesis. NSF fibroblasts synthesized excess levels of hyaluronan and collagen compared with control fibroblasts, with up to 2.8‐fold and 3.3‐fold increases, respectively. NSF patient serum stimulated control fibroblast hyaluronan synthesis by up to 7‐fold, and collagen synthesis by up to 2.4‐fold. 1 mM gadodiamide added to culture medium stimulated fibroblast growth in a dose‐dependent manner, decreasing their doubling time from 28 h to 22 h, and increasing the maximum cell density. Even a short exposure to gadodiamide stimulated cell growth, suggesting that the cells were activated by the gadodiamide. The growth of fibroblasts within contracted collagen lattices was also significantly stimulated by gadodiamide, while fibroblasts exposed to gadodiamide synthesized increased levels of hyaluronan. Control fibroblasts exposed to gadodiamide, and NSF fibroblasts exhibited an extensive pericellular coat of hyaluronan, and expressed α‐smooth muscle actin. Gadolinium chloride did not affect fibroblast growth. This report demonstrates that NSF fibroblasts synthesize excess levels of hyaluronan and collagen, and that gadodiamide stimulates control fibroblast growth, matrix synthesis, and differentiation into myofibroblasts, suggesting a possible role for gadodiamide in the pathophysiology of NSF. Copyright © 2008 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
Expression of pentraxin 3 (PTX3) in human atherosclerotic lesions
Authors: Savchenko AS , Imamura M , Ohashi R , Jiang S , Kawasaki T , Hasegawa G , Emura I , Iwanari H , Sagara M , Tanaka T , Hamakubo T , Kodama T , Naito M
Published: January 2008

Pentraxin 3 (PTX3) and C‐reactive protein (CRP) are members of the pentraxin superfamily. PTX3 expression is induced in response to inflammatory signals, and is produced at sites of inflammation by several types of cell, primarily monocytes/macrophages, dendritic cells (DCs), endothelial cells, smooth muscle cells (SMCs), and fibroblasts, but is not produced by hepatocytes, which are a major source of CRP. The aim of our study was to investigate the expression pattern of PTX3 in human atherosclerotic lesions using a novel monoclonal antibody against PTX3. We examined coronary arterial thrombi containing an atherosclerotic plaque component removed from patients with acute myocardial infarction and human aortic tissues with various degrees of atherosclerosis sampled from autopsy cases. Immunohistochemical study of paraffin and frozen sections indicated that macrophages, mainly foam cells, expressed PTX3 in advanced atherosclerotic lesions. Interestingly, we also clearly observed PTX3‐positive neutrophils infiltrating into atherosclerotic plaques, suggesting that PTX3 derived from neutrophils as well as macrophages plays an important role in atherogenesis. Copyright © 2008 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
Solar power generation using high altitude platforms feasibility and viability
Authors: Aglietti G. S. , Markvart T. , Tatnall A. R. , Walker S. J.
Published: January 2008

This paper investigates the feasibility and economical advantages that could be offered by a new facility for the production of solar energy. The basic concept is to exploit a high altitude aerostatic platform to support Photovoltaic (PV) modules to substantially increase their output by virtue of the significantly enhanced solar radiation at the operating altitude of the aerostat. The electric energy is then transmitted to the ground using the aerostat mooring cable. The technical feasibility of the concept is demonstrated by using standard equations and realistic values for the relevant engineering parameters that describe the technical properties of the materials and subsystems. There are, nevertheless, issues to be addressed to improve the performance; however, none of these issues is deemed to negate the technical feasibility of this concept. A preliminary cost model is illustrated and using unit cost data for the various materials and subsystems it is shown that it is possible to identify a specific size that minimizes the cost of energy produced. This cost could be considerably lower than what can be achieved by solar panels based on the ground in the UK. Copyright © 2008 John Wiley & Sons, Ltd.
Recent excursions to the borderlands between the realms of concerted and stepwise: carbocation cascades in natural products biosynthesis
Authors: Tantillo Dean J.
Published: January 2008

Recent theoretical studies on concerted carbocation rearrangements that involve multiple asynchronous chemical events are described. The relevance of such rearrangements to natural products biosynthesis is highlighted. Copyright © 2008 John Wiley & Sons, Ltd.
Short‐circuit current improvement of CuGaSe2 solar cells with a ZnS/(Zn,Mg)O buffer combination
Authors: Witte Wolfram , Hariskos Dimitrios , Kniese Robert , Powalla Michael
Published: January 2008

CuGaSe2 (CGS) thin‐film solar cells were prepared with an in‐line co‐evaporation process and the established buffer combination CdS/i‐ZnO was replaced by ZnS/(Zn,Mg)O. We obtained functional CGS solar cells with a strong gain in the short‐circuit current density as compared to the CdS/i‐ZnO buffer reference cells. The enhanced current density is a result of improved transmission in the wavelength region between 330 nm and 550 nm of the ZnS/(Zn,Mg)O buffer combination as compared to CdS/i‐ZnO. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Rapid and sensitive analysis of vincristine in human plasma using on‐line extraction combined with liquid chromatography/tandem mass spectrometry
Authors: Corona Giuseppe , Casetta Bruno , Sandron Sara , Vaccher Emanuela , Toffoli Giuseppe
Published: January 2008

A simple and rapid method has been developed and validated for the quantitation of vincristine in human plasma by liquid chromatography/tandem mass spectrometry (LC/MS/MS) with atmospheric pressure chemical ionization using on‐line solid‐phase extraction. The method uses vinblastine as internal standard and the sample preparation is limited just to a plasma protein precipitation step. Further sample clean‐up is carried out on‐line through a perfusion column preceding an analytical phenyl LC column, the latter directly connected to the mass spectrometer. Quantitation is performed in multiple reaction monitoring mode using the transitions of m/z 825.3 → 765.3 and 811.3 → 751.3 for vincristine and vinblastine respectively. The assay was linear (r2 ≥0.99) in a concentration range from 0.1 to 500 ng/mL. Carry‐over, measured on the experimental set‐up, was less than 0.04%. Recovery for vincristine and the internal standard was within 90–95%. The intra‐day and inter‐day assay precision ranged from 1.2% to 6.8% RSD while mean percentage deviation from nominal value ranged from 0.01% to 6.1%. The proposed assay was found suitable for pharmacokinetics investigations and clinical therapeutic drug monitoring especially in pediatric cancer patients. Copyright © 2008 John Wiley & Sons, Ltd.
Study of doubly charged alkaline earth metal and 3‐azidopropionitrile complexes by electrospray ionization mass spectrometry
Authors: Couto Narciso , Ramos M. João , Fernandez M. Tereza , Rodrigues Paula , Barros M. Teresa , Costa M. Lourdes , Cabral Benedito J. Costa , Duarte M. Filomena
Published: January 2008

The present work describes a study of the complexation of calcium and magnesium by 3‐azidopropionitrile by means of electrospray ionization mass spectrometry (ESI‐MS). Complexes were obtained from solutions of calcium and magnesium salts of the type CaX2 and MgX2 (where X = Cl or NO3) in water and methanol/water. The complexes detected were mainly double positively charged, with various stoichiometries not depending on the solvent, since water and 3‐azidopropionitrile were always the main ligands. Solvation with methanol was not observed unlike in a previous study of complexation of nickel and cobalt by 3‐azidopropionitrile. The complex ions [M(II)Az4(H2O)]2+, [M(II)Az5]2+ (where M = Ca and Mg) are the most abundant for both metals, and both counter ions. Tandem mass spectrometric (MS/MS) analysis showed that, under collision‐induced dissociation (CID) conditions, the most important processes occurring were loss of neutral ligands and the replacement of 3‐azidopropionitrile by water. A complex species containing reduced alkaline earth metal was due to radical loss, resulting from homolytic cleavage in the azide ligand. Some terminal ions, in the fragmentation sequences, point to the nitrile group as the coordination site in the 3‐azidopropionitrile. Density functional theory (DFT) calculations confirmed this coordination site and proved that 3‐azidopropionitrile behaves as a monodentate ligand in the systems under study. Moreover, the theoretical study proved that the presence of water ligand introduces stability through a hydrogen bond established between the water molecule and one nitrogen atom of the azido group. In addition, the strong dipole moment of 3‐azidopropionitrile (4.76 D), which is mainly related to presence of the nitrile group, favors the stabilization of the metal‐ligand complexes through charge‐dipole interactions and the coordination of the metal to the nitrile group. Copyright © 2008 John Wiley & Sons, Ltd.
New Classification of Cystic Duct Carcinoma
Authors: Yokoyama Y. , Nishio H. , Ebata T. , Abe T. , Igami T. , Oda K. , Nimura Y. , Nagino M.
Published: January 2008

Background

Farrar’s criteria for cystic duct carcinoma (histopathologic diagnosis of a carcinoma strictly limited to the cystic duct) are impractical especially when making a diagnosis of primary cystic duct carcinoma in its advanced stage. Therefore, in our previous study, we proposed a new definition of cystic duct carcinoma: a gallbladder tumor, the center of which is located in the cystic duct. In this study, we further propose a new classification for cystic duct carcinomas diagnosed by our definition.

Patients and methods

This study included 44 surgical patients with cystic duct carcinoma diagnosed by our criteria. These patients were further classified into two groups: hepatic hilum type (HH, n = 29), in which the tumor mainly invades the hepatic hilum, and cystic confluence type (CC, n = 15), in which the tumor mainly involves the confluence of the cystic duct. The clinicopathologic features of these two groups were analyzed retrospectively.

Results

There was more papillary or well differentiated adenocarcinoma in the CC type lesions than in the HH type. The perineural and vascular invasion were more common in the HH type than in the CC type. The survival rate tends to be higher for patients with the CC type than for those with the HH type (p = 0.064). Moreover, we found a significantly different sex ratio between these two groups (female sex was predominant for the HH type, whereas male sex was predominant for the CC type).

Conclusion

Our new classification showed two distinct types of advanced cystic duct carcinoma, which may help in understanding the clinical characteristics of the carcinoma originated in the cystic duct.
Heraklas on Knots: Sixteen Surgical Nooses and Knots from the First Century A.D.
Authors: Hage J. Joris
Published: January 2008

In the first century of our common era, the Greek physician Heraklas wrote a brief essay on how to tie 16 knots and nooses for surgical and orthopedic purposes. His work is reintroduced and discussed here because its place in the origin and evolution of surgery needs to be properly acknowledged and recorded in the current medical literature. To do so, Raeder’s definitive Greek edition of the oldest extant manuscripts of Heraklas’ essay was studied along with the various illustrated interpretations of his text published over the last six centuries. Moreover, the contemporary literature was searched for current applications of Heraklas’ knots by use of a database of surgical knots. It was found that seven of Heraklas’ 16 knots and nooses were still applied surgically of late, and that four of these have even been recently rediscovered for such applications. Therefore, it is concluded that Hellenistic, Roman, and Byzantine medicine had a rich knowledge and high standards. Contemporary surgical techniques may be found to be truly ancient if we search deep enough, far enough, and long enough.
Limitations of Intraoperative Adrenal Remnant Volume Measurement in Patients Undergoing Subtotal Adrenalectomy
Authors: Brauckhoff Michael , Stock Karsten , Stock Susanne , Lorenz Kerstin , Sekulla Carsten , Brauckhoff Katrin , Thanh Phuong Nguyen , Gimm Oliver , Spielmann Rolf Peter , Dralle Henning
Published: January 2008

Background

Recent studies have shown that a minimum of approximately one‐third of one normal adrenal gland is required for sufficient adrenocortical stress capacity. Correlation between intraoperative measurement, determination of remnant size by computed tomography (CT), and adrenocortical stress capacity has not been examined so far.

Methods

Twenty‐two patients with familial pheochromocytoma (n = 13), sporadic pheochromocytoma (n = 3), and adrenocortical tumors (n = 6) who underwent unilateral or bilateral subtotal adrenalectomy (STAE, 28 adrenal remnants) were prospectively studied. Patients were examined in a multi‐slice CT to determine residual adrenal tissue and by ACTH test 4 days and 3 months postoperatively.

Results

There was a slight significant correlation between intraoperative and CT calculated volumes (r = 0.77; p < 0.001). However, volumes assessed by CT were almost doubled compared with intraoperative determination (p < 0.001). Although recovery of adrenal function could be observed, no significant changes of remnant volumes could be detected within 3 months. In patients with familial pheochromocytoma, there was a significant correlation between residual adrenal volume and stimulated cortisol levels (P < 0.001). A distinct minimum of adrenal volume for intact adrenocortical stress capacity could not be exactly determined; however, in one patient with only 10% residual adrenal tissue intact stress capacity was found.

Conclusions

Residual adrenal tissue of approximately 10–15% offers intact stress capacity. However, an exact determination of the size of an adrenal remnant after STAE has limitations. CT gives larger volumes compared with intraoperative determination. For calculation of a volume–function correlation of residual adrenal tissue, in clinical practice, the determination of relative adrenal residual volume is acceptable.
Length of Stay: An Inappropriate Readout of the Success of Enhanced Recovery Programs
Authors: Maessen J. M. C. , Dejong C. H. C. , Kessels A. G. H. , von Meyenfeldt M. F. ,   Enhanced Recovery After Surgery (ERAS) Group
Published: January 2008

Background

Enhanced recovery after surgery (ERAS) programs are designed to reduce hospital length of stay by shortening the postoperative recovery period. The intended effect of an accelerated recovery on the length of stay may be frustrated by a delayed discharge. This study was designed to assess the influence of an ERAS program on the proportion, appropriateness, and extent of delay in discharge.

Methods

Patients who enrolled in the ERAS program (n = 121) between 2003 and 2006 were compared with 52 patients who were managed traditionally in 2001.

Results

Ninety percent of the pre‐ERAS patients and 87% of the ERAS patients were not discharged on the day that discharge criteria were fulfilled. The additional stay of 59% of the pre‐ERAS patients and 69% of the ERAS patients was inappropriate. Wound care (15% in the pre‐ERAS and 3% of the ERAS group) and observation of any symptoms pointing to an anastomotic leakage (10% in both groups) were the most important reasons for a medical appropriate delay of discharge. The extent of delay in discharge decreased significantly from a median of two days in the pre‐ERAS group to a median of 1 day in the ERAS group (p = 0.004).

Conclusions

Reductions in length of stay up to a median of 2 days after start of an enhanced recovery program may relate to changes in organization of care and not to a shorter recovery period. Recovery statistics should replace or at least be added to the length of stay as outcome of enhanced recovery programs.
A Critical Analysis of Laparoscopic Appendectomy: How Experience with 1,400 Appendectomies Allowed Innovative Treatment to Become Standard in a University Hospital
Authors: Schick Kerstin S. , Hüttl Thomas P. , Fertmann Jan M. , Hornung Hans‐Martin , Jauch Karl‐Walter , Hoffmann Johannes N.
Published: January 2008

Background

Although advantages of laparoscopic appendectomy (LA) have not yet been proved, there is increasing evidence that LA provides diagnostic and therapeutic advantages as compared to conventional surgery. This article reports the introduction of LA in a university hospital where LA now represents the standard operative procedure in patients with suspected appendicitis.

Methods

Consecutive patients with appendectomy were prospectively included in the surgical database from 5/1991 to 10/2005. Operating time skin‐to‐skin in minutes, conversion from laparoscopy to open appendectomy, and complications requiring reoperation as well as surgical expertise were recorded.

Results

After initial performance of LA by four experienced specialists in laparoscopic surgery between 1991 and 1994, LA was routinely implemented from 1995 to 2005. Laparoscopic appendectomy was performed in 1,012 patients, and conventional appendectomy in 449 patients, with a LA rate of about 90% in recent years. Intraoperative conversion was deemed necessary in 62 patients (6.2 %) by 40 surgeons among the 103 surgeons who performed LA over 14 years with a mean operative time of 57 ± 2 min. Between 1995 and 2005 about 25%–30% of LAs were performed as the first LA for the respective surgeon. Laparoscopic appendectomy was associated overall with a reduced length of stay in the hospital compared to open appendectomy (LA: 4.4 ± 0.1 days versus 6.6 ± 0.2 in open appendectomy; p < 0.001).

Conclusions

This analysis provides evidence that LA can be introduced in an university hospital with acceptable results despite low operation numbers per surgeon and a liberal teaching policy. The LA procedure, which is associated with a 2%–4% rate of reoperation, may serve as laparoscopy training for young surgeons.
Surgeon Performed Ultrasound Facilitates Minimally Invasive Parathyroidectomy by the Focused Lateral Mini‐incision Approach
Authors: Soon Patsy S. H. , Delbridge Leigh W. , Sywak Mark S. , Barraclough Beverley M. , Edhouse Pam , Sidhu Stan B.
Published: January 2008

Background

Minimally invasive parathyroidectomy (MIP) is now widely accepted where a single adenoma can be localized preoperatively. In our unit, MIP is offered once a parathyroid adenoma is localized with a sestamibi (MIBI) scan, with or without a concordant neck ultrasound. The aim of this study was to compare the accuracy of surgeon performed ultrasound (SUS) with radiologist performed ultrasound (RUS) in the localization of a parathyroid adenoma in MIBI‐positive primary hyperparathyroidism (PHPT).

Patients and Methods

This is a prospective study of patients undergoing parathyroidectomy for sporadic primary hyperparathyroidism (PHPT) from April 2005 to October 2006 at the University of Sydney Endocrine Surgical Unit. Patients were then divided into those who underwent preoperative RUS or SUS.

Results

Two‐hundred eighteen patients formed the study group. One hundred forty‐eight (66%) patients had RUS and 87 (39%) had SUS. Overall, RUS correctly localized the parathyroid adenomas in 121 of 148 (82%) patients. Surgeon performed ultrasound correctly localized the abnormal parathyroid adenoma in 72 of 87 (83%) of cases. There was no significant difference in the proportion of patients with single gland disease, double adenomas, or hyperplasia correctly localized by SUS or RUS. Incorrect interpretation of ultrasound imaging was due to cystic degeneration in thyroid nodules, lymph nodes, retro‐esophageal location of adenomas and ectopic and small parathyroid glands.

Conclusions

Surgeon performed ultrasound is a useful adjunctive tool to MIBI localization for facilitating MIP and when performed by experienced parathyroid surgeons, it can achieve accuracy rates equivalent to that of a dedicated parathyroid radiologist.
On the Non-Existence of Optimal Solutions and the Occurrence of “Degeneracy” in the CANDECOMP/PARAFAC Model
Authors: Krijnen Wim P. , Dijkstra Theo K. , Stegeman Alwin
Published: January 2008

The CANDECOMP/PARAFAC (CP) model decomposes a three-way array into a prespecified number of R factors and a residual array by minimizing the sum of squares of the latter. It is well known that an optimal solution for CP need not exist. We show that if an optimal CP solution does not exist, then any sequence of CP factors monotonically decreasing the CP criterion value to its infimum will exhibit the features of a so-called “degeneracy”. That is, the parameter matrices become nearly rank deficient and the Euclidean norm of some factors tends to infinity. We also show that the CP criterion function does attain its infimum if one of the parameter matrices is constrained to be column-wise orthonormal.
A quantitative study of testicular germ cell populations in masculinized neomale common carp (Cyprinus carpio L.)
Authors: Hulak M. , Psenicka M. , Coward K. , Linhart O.
Published: January 2008

The main objective of the present study was to investigate the effects of 17α‐methyltestosterone treatment upon the testicular germ cells of gynogenetic masculinized neomale common carp (Cyprinus carpio L.) in comparison with diploid carp. Gynogenetic common carp progeny (mean body weight, BW, 2.6 ± 0.3 g; mean total length, 10.4 ± 0.5 cm) were treated for a period of 40 days with 17α‐methyltestosterone (MT) at a dose of 100 mg kg−1. The oral administration of MT resulted in 61.5–100% of fish exhibiting male gonads. The masculinized neomales exhibited reduced (P < 0.05) body weight (BW = 22.9 ± 0.8) but significantly increased (P < 0.05) mean testis weight (2.1 ± 0.3) and mean gonadosomatic index (GSI = 9.5 ± 0.2%) in comparison with fish not treated with MT (BW 54.8 ± 1.3; GSI = 0.61%). Furthermore, treatment with MT also resulted in an increased number of fish exhibiting abnormal gonads. However, neomales did not exhibit abnormalities in the development of sperm ducts. MT treatment significantly increased germ cell volume, nuclear diameter, nuclear volume and cyst volume (P < 0.01 in all cases) in MT‐treated fish compared to untreated fish. The area occupied by seminiferous tubules, the number of Sertoli cells and germ cells per cyst, and the number of Leydig cells were significantly (P < 0.05) greater in fish treated with MT. The carp neomales exhibited approximately 20–60% more Sertoli cells per cyst (P < 0.05). Leydig cell nuclear volume and Leydig cell individual volume were significantly reduced in MT‐treated groups (P < 0.05) compared with untreated groups. In conclusion, our study strongly suggests that the abnormal gonadal structure evident in masculinized neomales could be explained by a combination of MT‐induced genetic (homozygosity) and anabolic effects (upon germ and somatic cells).