bluuebunny/crossref_metadata_2025 huggingface dataset:
ChemInform Abstract: Carbo‐mers: From Skeleton to Function
Authors: Maraval Valerie , Chauvin Remi
Published: January 2008

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Synthetic Studies on Fostriecin and Related Natural Products
Authors: Miyashita Kazuyuki , Ikejiri Masahiro , Tsunemi Tomoyuki , Matsumoto Ayumi , Imanishi Takeshi
Published: January 2008

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Atomistic Simulation of the Thermodynamic and Transport Properties of Ionic Liquids
Authors: Maginn Edward J.
Published: January 2008

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Non‐Reactive and Reactive Wetting of Liquids on Surfaces
Authors: Kumar Girish , Prabhu K. Narayan
Published: January 2008

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
Modellbasierte Führungsstrategie für die Foulingminimierung in Membranbioreaktoren
Authors: Arellano‐Garcia H. , Drews A. , Kraume M.
Published: January 2008

Membranbioreaktoren (MBR) sind eine noch vergleichsweise junge Technologie, deren Anwendung dem fundamentalen Verständnis der beteiligten Phänomene und ihrer Interaktionen z. T. vorauseilt. Die Auslegung der benötigten Membranfläche in MBR erfolgt bislang auf Basis von Experimenten. Im Verlauf der Filtration kommt es zu verschiedenen Ablagerungen auf und in der Membran. Im Laufe der Zeit tritt irreversibles Fouling auf, das chemische Reinigungen notwendig macht. Im vorliegenden Beitrag wird eine modellbasierte Führungsstrategie für die Fouling‐Minimierung in Membranbioreaktoren auf Basis der Auswertung von online verfügbaren Daten und optimierter Modell‐ sowie Parameteridentifikation entwickelt. Hierfür wird die strukturelle Identifizierbarkeit der zur Verfügung stehenden Modelle untersucht und ein Ansatz zur automatisierten Erkennung des aktuell herrschenden Filtrationsmechanismus implementiert.
Investigating Alanine–Silica Interaction by Means of First‐Principles Molecular‐Dynamics Simulations
Authors: Nonella Marco , Seeger Stefan
Published: January 2008

In our attempts to achieve a detailed understanding of protein–silica interactions at an atomic level we have, as a first step, simulated a small system consisting of one alanine in different protonation states, and a hydroxylated silica surface, using a first‐principles molecular‐dynamics technique. The simulations are carried out in vacuo as well as in the presence of water molecules. In the case of a negatively charged surface and an alanine cation, an indirect proton transfer from the alanine carboxylic group to the surface takes place. The transfer involves several water molecules revealing an alanine in its zwitterionic state interacting with the neutral surface through indirect hydrogen bonds mediated by water molecules. During the simulation of the zwitterionic state the ammonium group eventually establishes a direct NH⋅⋅⋅OSi interaction, suggesting that the surface–amino group interaction is stronger than the interaction between the surface and the carboxylic group. In vacuum simulations, the amino group exhibits clearly stronger interactions with the surface than the carboxylic group.
Therapeutic education of diabetic patients
Authors: Golay A. , Lagger G. , Chambouleyron M. , Carrard I. , Lasserre‐Moutet A.
Published: January 2008

Therapeutic patient education is a patient‐centred approach, focussed on patients' needs, resources, values and strategies. It allows patients to improve their knowledge and skills not only concerning their illness but also their treatment. It brings a better quality of life, a greater therapeutic compliance and a reduction in complications. The most difficult part of therapeutic patient education occurs when patients must change their behaviour. Motivational interviewing and cognitive‐behavioural approaches contribute greatly here and allow both the preparation and support of patients during progressive ‘step by step’ change. The work on resistance to change is fundamental, and ambivalence when faced with the choice of a new way of life must be measured, discussed and negotiated. Patients become partners and we become ‘coaches’. The negotiation of objectives must allow patients to choose their own strategies, which normally should cost them the least possible, psychologically, and bring them the maximum benefit.

The efficiency of therapeutic patient education no longer needs to be proved: 80% less amputations over 10 years in diabetic patients; 50% maintenance of weight loss over 5 years, etc.

In conclusion, therapeutic education is part of a humanistic medical approach centred on patients; it allows them to be active participants in their own treatment with the aim of improving their quality of life and therapeutic compliance, as well as reducing potential complications. Thus, health care professionals teach, inform, train, negotiate with, motivate and accompany patients in the long‐term follow‐up of their illness. Copyright © 2008 John Wiley & Sons, Ltd.
A novel probe for chemiluminescent image detection of proteins in two‐dimensional gel electrophoresis
Authors: Liu Jia , Ouyang Jin , Baeyens Willy R. G. , Delanghe Joris R. , Wang Zhenzhen , Liu Jinxiu , Zhang Huiying
Published: January 2008

Carrier ampholytes were found to enhance the chemiluminescence (CL) emission from the 3‐aminophthalic hydrazide (luminol)‐hydrogen peroxide system. They can be used as a chemiluminescent probe for rapid detection of major proteins in gels. This probe attracted much interest due to its ability to attach proteins, and to the possibility to combine it with separation techniques generating the CL emission directly. Increased signal intensity was achieved employing optimized concentrations of the carrier ampholyte enhancer. The binding of carrier ampholyte to proteins was found to occur at the pI of the proteins. Proteins from different regions of the gels were identified by their matrix‐assisted TOF mass spectra and by appropriate database search, the results illustrating the possibility of major protein detection in human serum. Direct CL image detection with the carrier ampholyte probe can be applied for the detection of characteristic proteins in patients, i.e., proteins which cannot be detected without the probe.
Protein extraction for 2‐DE from the lamina of Ecklonia kurome (laminariales): Recalcitrant tissue containing high levels of viscous polysaccharides
Authors: Nagai Kouhei , Yotsukura Norishige , Ikegami Haruka , Kimura Hajime , Morimoto Koichi
Published: January 2008

Extraction of proteins from the tissues of laminarialean algae, i.e. kelp, is difficult due to high levels of nonprotein interfering compounds, mainly viscous polysaccharides. To establish proteomic analysis of kelp species, an ethanol/phenol extraction method was developed and compared to other popular methods. Proteins were extracted with phenol from crude protein powder, obtained by homogenizing the kelp tissues in ice‐cold ethanol. The ethanol/phenol method produced high‐quality proteins of the highest purity from the lamina of Ecklonia kurome, one of the Japanese dominant laminarialean algae. This method gave well‐resolved 1‐D SDS‐PAGE or 2‐DE images with low background and the highest number of bands or spots. In particular, proteins with neutral to basic pI′s were efficiently extracted. Furthermore, 27 spots on the 2‐DE gel were extensively identified by MALDI‐TOF/TOF analysis. To the best of our knowledge, this is the first report of a protocol for protein extraction from kelp tissues that gives satisfactory 2‐D protein profiles. It is expected that the protocol can be applied to other algae tissues or other recalcitrant plant tissues containing high levels of nonprotein interfering compounds.
Anaplastic lymphoma of the cervical esophagus presenting as a tracheoesophageal fistula
Authors: Joshi Anil , Fields Paul , Simo Ricard
Published: January 2008

Background

Anaplastic kinase‐1 positive lymphoma (ALK‐1) is a very rare but distinct pathologic entity. ALK‐1 lymphoma tends to affect the bone marrow, skin, lungs, soft tissue, but very rarely the gastrointestinal tract.

Methods

We report a case of ALK‐1 positive lymphoma presenting as a tracheoesophageal fistula. The clinical presentation, histopathology, and management outcome are all discussed.

Conclusion

ALK‐1 positive lymphoma of the upper aerodigestive involvement is extremely rare. An unusual presentation such as pharyngeal pouch with vocal cord palsy should suggest pathology. Histopathologic analysis can be difficult and immunohistochemical studies will aid are of paramount importance in the diagnosis and help in subsequent management and also act as prognostic indicators. © 2008 Wiley Periodicals, Inc. Head Neck, 2008
Genetic alterations in juvenile nasopharyngeal angiofibromas
Authors: Coutinho‐Camillo Cláudia M. , Brentani M. Mitzi , Nagai Maria A.
Published: January 2008

Juvenile nasopharyngeal angiofibroma (JNA) is a rare benign neoplasm of the nasopharynx that accounts for 0.5% of all head and neck tumors. Although histologically benign in appearance, JNAs are locally aggressive and destructive, spreading from the nasal cavity to the nasopharynx, paranasal sinuses, and orbit skull base with intracranial extension. The gender selectivity of JNA and the relatively young age at diagnosis suggest hormone‐dependent development. Hormonal disorders have been reported in patients with JNA, and androgen and estrogen receptors have been identified in tumor tissue; however, a hormonal influence on JNA is controversial. Recent studies have attempted to further delineate the pathogenesis of JNA through analysis of genetic and molecular changes. Understanding of the molecular mechanisms involved in JNA might improve prevention, prognosis, and treatment of this tumor. In this review, we discuss published studies addressing the possible molecular pathways that might be involved in the development of JNA. © 2008 Wiley Periodicals, Inc. Head Neck, 2008
Oncologic outcomes of transoral laser surgery of supraglottic carcinoma compared with a transcervical approach
Authors: Cabanillas Rubén , Rodrigo Juan Pablo , Llorente Jose Luis , Suárez Carlos
Published: January 2008

Background

To evaluate the oncologic effectiveness of transoral laser surgery of supraglottic cancer, we compared a group of patients treated with laser surgery, with a stage‐matched group treated with a transcervical approach.

Methods

Twenty‐six patients who underwent laser surgery were retrospectively compared with 26 patients who underwent a transcervical approach. In both groups, the patients were classified as follows: 8% stage I, 23% stage II, 46% stage III, and 23% stage IV.

Results

The 5‐year disease‐specific survival rates were 80% for the laser group and 72% for the transcervical group (p = .5). The ultimate 5‐year laryngeal preservation rate was 86% in the laser group and 80% in the transcervical group (p = .6). In both arms, all patients classified as T1 and T2 who survived 5 years after the surgical treatment of tumors retained the larynx.

Conclusions

The oncologic results of transoral laser surgery of supraglottic cancer are equivalent to those of the classic transcervical approach. © 2008 Wiley Periodicals, Inc. Head Neck, 2008
Fluorescent labeled anti‐EGFR antibody for identification of regional and distant metastasis in a preclinical xenograft model
Authors: Gleysteen John P. , Newman J. Robert , Chhieng David , Frost Andra , Zinn Kurt R. , Rosenthal Eben L.
Published: January 2008

Background

Detection of regional and distant metastatic disease has significant implications for patient management. Fluorescent imaging may be a useful technique for metastasis detection and removal.

Methods

Anti–epidermal growth factor receptor antibody (cetuximab) and isotype‐matched control antibody (immunoglobulin G [IgG]) were labeled with a near‐infrared fluorophore (Cy5.5), then systemically administered to mice with tumors resulting from either intraoral or intravenous injections of head and neck squamous cell carcinoma. Mice were sacrificed before undergoing fluorescent stereomicroscopy to assess pulmonary or cervical lymph node metastasis. Fluorescent areas were serially excised until wound bed demonstrated negative fluorescence.

Results

Mice bearing pulmonary metastases displayed diffuse background after IgG–Cy5.5 injection, but demonstrated a speckled fluorescent pattern across lung surface following cetuximab–Cy5.5 injection. Mice bearing cervical metastases demonstrated clear fluorescence of primary tongue tumor and bilateral cervical nodes. Fluorescence correlated with histopathology.

Conclusion

These data suggest that cetuximab–Cy5.5 may have clinical utility in the detection and guided the removal of regional and distant micrometastasis. © 2008 Wiley Periodicals, Inc. Head Neck, 2008
Effect of polymer architecture on surface properties, plasma protein adsorption, and cellular interactions of pegylated nanoparticles
Authors: Sant Shilpa , Poulin Suzie , Hildgen Patrice
Published: January 2008

The aim of the present study was to evaluate the cellular interaction of nanoparticles (NPs) prepared from different pegylated polymers and elucidate the effect of polymer architecture, for instance, grafted versus block copolymer on their cellular uptake. Fluorescein‐labeled NPs of four different polymers, viz., poly(D,L‐lactide) (PLA), poly(ethylene glycol)1%‐graft‐poly(D,L‐lactide) (PEG1%‐g‐PLA), poly(ethylene glycol)5%‐graft‐poly(D,L‐lactide) (PEG5%‐g‐PLA), and (poly(D,L‐lactide)‐block‐poly(ethylene glycol)‐block‐poly(D,L‐lactide))n multiblock copolymer (PLA‐PEG‐PLA)n were prepared. These NPs were characterized for their size, ζ‐potential, and surface morphology. XPS studies revealed possibility of chemical interaction between PLA COOH groups and PVA OH groups, thus making it difficult to be washed off the NP surface completely. Grafted polymer NPs showed more surface PEG coverage than (PLA‐PEG‐PLA)n despite of their comparatively lower PEG content. The results of surface properties were translated into protein binding showing least amount of proteins bound to grafted copolymer NPs as against multiblock copolymer NPs. NPs showed no toxicity to RAW 264.7 cells. Cellular uptake of NPs was temperature and concentration‐dependent as well as involved clathrin‐mediated processes. Thus, this study confirms the importance of polymer architecture in determining the surface properties and hence, protein binding and cellular interactions of NPs. Also, it was shown that grafted copolymer NPs reduced macrophage uptake as compared to multiblock copolymer although mechanisms different than phagocytosis were involved. © 2008 Wiley Periodicals, Inc. J Biomed Mater Res, 2008
Polyurethane scaffold formation via a combination of salt leaching and thermally induced phase separation
Authors: Heijkants R. G. J. C. , van Calck R. V. , van Tienen T. G. , de Groot J. H. , Pennings A. J. , Buma P. , Veth R. P. H. , Schouten A. J.
Published: January 2008

Porous scaffolds have been made from twopolyurethanes based on thermally induced phase separation of polymer dissolved in a DMSO/water mixture in combination with salt leaching. It is possible to obtain very porous foams with a very high interconnectivity. A major advantage of this method is that variables like porosity, pore size, and interconnectivity can be independently adjusted with the absence of toxic materials in the production process. The obtained compression moduli were between 200 kPa and 1 MPa with a variation in porosity between 76 and 84%. Currently the biological and medical aspects are under evaluation. © 2008 Wiley Periodicals, Inc. J Biomed Mater Res, 2008
Osteogenic differentiation of human mesenchymal stem cells on chargeable polymer‐modified surfaces
Authors: Guo Likun , Kawazoe Naoki , Hoshiba Takashi , Tateishi Tetsuya , Chen Guoping , Zhang Xingdong
Published: January 2008

Polystyrene cell‐culture plates modified with positively charged polyallylamine (PAAm) and negatively charged poly(acrylic acid) (PAAc) and unmodified plate were used for the culture of human mesenchymal stem cells (MSCs) to study the effect of surface electrostatic properties on their osteogenic differentiation. All of these surfaces supported cell adhesion and proliferation. However, the cells adhered, spread, and proliferated somewhat more quickly on the PAAm‐modified surface than they did on the PAAc‐modified and control surfaces. Osteogenic differentiation was examined by alkaline phosphatase (ALP) staining, alizarin red S staining, and gene‐expression analysis. The MSCs cultured on the three kinds of surfaces in the presence of dexamethasone were positively stained with ALP and alizarin red S staining, while the cells cultured without dexamethasone were not positively stained. Gene‐expression analyses using real‐time PCR indicated that MSCs cultured on these surfaces in the presence of dexamethasone expressed osteogenic marker genes, encoding ALP, osteocalcin, bone sialoprotein, osteopontin, and type I collagen. These results indicate that the positively charged, negatively charged, and unmodified surfaces supported osteogenic differentiation, and that their effect required the synergistic effect of dexamethasone. © 2008 Wiley Periodicals, Inc. J Biomed Mater Res, 2008
A randomized, prospective, pharmacoeconomic trial of neoral 2-hour postdose concentration monitoring versus tacrolimus trough concentration monitoring in de novo liver transplant recipients
Authors: Shenoy Surendra , Hardinger Karen L. , Crippin Jeffrey , Korenblat Kevin , Lisker-Melman Mauricio , Lowell Jeffrey A. , Chapman William
Published: January 2008

Two-hour postdose cyclosporine (C2) monitoring is becoming an accepted method of therapeutic drug monitoring, although it is not known whether C2 monitoring is superior to tacrolimus (FK)-based immunosuppression. The purpose of this trial was to compare the safety, efficacy, and pharmacoeconomics of cyclosporine A (CsA) monitored by C2 levels versus FK monitored by trough levels in de novo liver transplant recipients. After informed consent, 60 de novo liver transplant recipients were randomized in a 1:1 fashion to receive either FK (trough, 6-10 ng/mL) or CsA (C2, 600-1200 ng/mL) and corticosteroids. The 2 groups were similar for gender, race, indication for liver disease, and age. At 1 year, patient survival was similar (93% for FK versus 90% for C2). One patient in the FK arm was retransplanted because of recurrent hepatitis C virus (HCV). Early acute rejection occurred in 27% of FK-treated patients and 23% of CsA-treated recipients [P = not significant (NS)]. Recurrent HCV occurred in 21% of FK-treated patients and 61% of CsA-treated patient (P = 0.04). The incidence of other infections, new onset diabetes mellitus, requirement for antihypertensives, and requirement for cholesterol medications were similar between the groups. Annual calcineurin inhibitor costs were lower in the C2 arm ($5432 ± 2091 for C2 versus $8291 ± 3948 for FK, P = 0.001). Annual pretransplant drug costs ($2292 ± 2331 for C2 versus $2831 ± 2358 for FK, P = NS) and 1-year posttransplant drug costs ($17,214 ± 16,600 for C2 versus $15,151 ± 11,699 for FK, P = NS) were similar. In conclusion, immunosuppression with CsA, monitored by C2 levels, is safe, effective, and economical in liver transplant recipients and provides immunosuppression at least equivalent to that of FK. Liver Transpl 14:173–180, 2008. © 2008 AASLD.
LIVER TRANSPLANTATION WORLDWIDE
Authors: Perkins James D.
Published: January 2008

Abstract

Background:

Hyperkalemia poses serious hazards to patients undergoing orthotopic liver transplantation (OLT), and its predictors have not been thoroughly examined.

Methods:

We retrospectively studied 1124 consecutive adult patients who underwent OLT. Hyperkalemia was defined as serum K+ > or =5.5 mmol/L. A total of 47 recipient, donor, intraoperative, and laboratory variables were initially analyzed in univariate analyses. Independent predictors of hyperkalemia in three periods of OLT (prereperfusion, early postreperfusion, and late postreperfusion) were determined in multivariate logistic regression analyses.

Results:

Of 1124 patients, 10.2%, 19.1%, and 7.9% had hyperkalemia in the prereperfusion, early postreperfusion, and late postreperfusion periods, respectively. Higher baseline K+ and red blood cell transfusion were independent predictors of prereperfusion hyperkalemia. Higher baseline K+ (or prereperfusion K+) and donation after cardiac death donor were independent predictors of early postreperfusion hyperkalemia. Higher baseline K+, longer warm ischemia time, longer donor hospital stay, lower intraoperative urine output, and the use of venovenous bypass were independent predictors of late postreperfusion hyperkalemia.

Conclusions:

Several laboratory, intraoperative, and donor variables were identified as independent predictors of hyperkalemia in the different periods. Such information may be used for more targeted preemptive interventions in patients who are at risk of developing hyperkalemia during adult OLT.
Novel Hyaluronan‐Based Nanocarriers for Transmucosal Delivery of Macromolecules
Authors: de la Fuente María , Seijo Begoña , Alonso María J.
Published: January 2008

The goal of this work was to design a new nanocarrier composed of the glycosaminoglycan hyaluronan and the polysaccharide chitosan, intended for the transmucosal delivery of macromolecules. The nanoparticles were characterized for their size and superficial charge. The incorporation of hyaluronan was verified by agarose gel electrophoresis and Fourier transform infrared (FT‐IR) spectroscopy. The ability of the nanosystems to encapsulate macromolecules was studied taking the hydrophilic protein bovine serum albumin (BSA) and the hydrophobic polypeptide Cyclosporine A (CyA) as models. Results showed that the experimental conditions could be conveniently adjusted in order to modulate the physicochemical properties of the carriers and their composition. Moreover, the nanoparticles provided high association efficiencies of the selected macromolecules.

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Complete assignment of the 1H and 13C NMR spectra of garciniaphenone and keto‐enol equilibrium statements for prenylated benzophenones
Authors: Derogis Priscilla B. M. C. , Martins Felipe T. , de Souza Thiago C. , de C. Moreira Maria E. , Souza Filho José D. , Doriguetto Antonio C. , de Souza Kamila R. D. , Veloso Marcia P. , Dos Santos Marcelo H.
Published: January 2008

This article reports the structural elucidation by IR, UV and MS spectroscopic data along with 1H and 13C NMR chemical shift assignments of two benzophenones isolated from the fruit pericarp of Garcinia brasiliensis Mart. (Clusiaceae): garciniaphenone, (1R,5S,7S)‐3‐benzoyl‐4‐hydroxy‐6,6‐dimethyl‐5,7‐di(3‐methyl‐2‐butenyl)bicyclo[3.3.1]non‐3‐ene‐2,9‐dione, a novel triprenylated benzophenone; and 7‐epi‐clusianone, a tetraprenylated benzophenone that has already been extracted from another species of the same family. Furthermore, the keto‐enol tautomeric equilibrium at solution‐state was described for these compounds by 1D and 2D NMR spectral methods and one attempt to rationalize the different ratios between the noted tautomers was based on stereochemical features. Copyright © 2008 John Wiley & Sons, Ltd.
Energy Efficient Emulsion Polymerization Strategies
Authors: Goikoetxea Monika , Heijungs Reinout , Barandiaran María J. , Asua José M.
Published: January 2008

Polymerization strategies aiming at further reducing the environmental impact of the already “green” emulsion polymerization process were investigated. Life cycle assessment showed that non‐isothermal strategies starting at low temperature resulted in an environmental impact lower than the isothermal ones. Nevertheless, the major part of the environmental impact was due to raw materials. The effect of the polymerization strategy on polymer microstructure was investigated.

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Pulmonary perfusion imaging in the rodent lung using dynamic contrast‐enhanced MRI
Authors: Mistry Nilesh N. , Pollaro James , Song Jiayu , De Lin Ming , Johnson G. Allan
Published: January 2008

With the development of various models of pulmonary disease, there is tremendous interest in quantitative regional assessment of pulmonary function. While ventilation imaging has been addressed to a certain extent, perfusion imaging for small animals has not kept pace. In humans and large animals perfusion can be assessed using dynamic contrast‐enhanced (DCE) MRI with a single bolus injection of a gadolinium (Gd)‐based contrast agent. But the method developed for the clinic cannot be translated directly to image the rodent due to the combined requirements of higher spatial and temporal resolution. This work describes a novel image acquisition technique staggered over multiple, repeatable bolus injections of contrast agent using an automated microinjector, synchronized with image acquisition to achieve dynamic first‐pass contrast enhancement in the rat lung. This allows dynamic first‐pass imaging that can be used to quantify pulmonary perfusion. Further improvements are made in the spatial and temporal resolution by combining the multiple injection acquisition method with Interleaved Radial Imaging and “Sliding window‐keyhole” reconstruction (IRIS). The results demonstrate a simultaneous increase in spatial resolution (<200 μm) and temporal resolution (<200 ms) over previous methods, with a limited loss in signal‐to‐noise‐ratio. Magn Reson Med 59:289–297, 2008. © 2008 Wiley‐Liss, Inc.
In vivo T1ρ mapping in cartilage using 3D magnetization‐prepared angle‐modulated partitioned k‐space spoiled gradient echo snapshots (3D MAPSS)
Authors: Li Xiaojuan , Han Eric T. , Busse Reed F. , Majumdar Sharmila
Published: January 2008

For T1ρ quantification, a three‐dimensional (3D) acquisition is desired to obtain high‐resolution images. Current 3D methods that use steady‐state spoiled gradient‐echo (SPGR) imaging suffer from high SAR, low signal‐to‐noise ratio (SNR), and the need for retrospective correction of contaminating T1 effects. In this study, a novel 3D acquisition scheme—magnetization‐prepared angle‐modulated partitioned‐k‐space SPGR snapshots (3D MAPSS)—was developed and used to obtain in vivo T1ρ maps. Transient signal evolving towards the steady‐state were acquired in an interleaved segmented elliptical centric phase encoding order immediately after a T1ρ magnetization preparation sequence. RF cycling was applied to eliminate the adverse impact of longitudinal relaxation on quantitative accuracy. A variable flip angle train was designed to provide a flat signal response to eliminate the filtering effect in k‐space caused by transient signal evolution. Experiments in phantoms agreed well with results from simulation. The T1ρ values were 42.4 ± 5.2 ms in overall cartilage of healthy volunteers. The average coefficient‐of‐variation (CV) of mean T1ρ values (N = 4) for overall cartilage was 1.6%, with regional CV ranging from 1.7% to 8.7%. The fitting errors using MAPSS were significantly lower (P < 0.05) than those using sequences without RF cycling and variable flip angles. Magn Reson Med 59:298–307, 2008. © 2008 Wiley‐Liss, Inc.
Spectral simplification for resolved glutamate and glutamine measurement using a standard STEAM sequence with optimized timing parameters at 3, 4, 4.7, 7, and 9.4T
Authors: Yang Shaolin , Hu Jiani , Kou Zhifeng , Yang Yihong
Published: January 2008

The C4 multiplet proton resonances of glutamate (Glu) around 2.35 ppm and glutamine (Gln) around 2.45 ppm usually overlap in MR spectra, particularly at low‐ and mid‐field strengths (1.5–4.7T). A spectral simplification approach is introduced that provides unobstructed Glu and Gln measurement using a standard STEAM localization sequence with optimized interpulse timings. The underlying idea is to exploit the dependence of response of a coupled spin system on the echo time (TE) and mixing time (TM) to find an optimum timing set (TE, TM), at which the outer‐wings of C4 “pseudo‐triplet” proton resonances of Glu and Gln are significantly suppressed while the central peaks are maintained. The spectral overlap is thus resolved as the overlap exists exclusively at the outer‐wings and the central peaks are readily separated due to the approximate 0.1‐ppm difference in chemical shift. Density matrix simulation for Glu, Gln, and other overlapping metabolites at 2.3–2.5 ppm was conducted to predict the optimum timing sets. The simulated, phantom, and in vivo results demonstrated that the C4 multiplet proton resonances of Glu and Gln can be resolved for unobstructed detection at 3T, 4T, and 4.7T. For simplicity, only simulated data are illustrated at 7T and 9.4T. Magn Reson Med 59:236–244, 2008. © 2008 Wiley‐Liss, Inc.
ACUT2E TSE‐SSFP: A hybrid method for T2‐weighted imaging of edema in the heart
Authors: Aletras Anthony H. , Kellman Peter , Derbyshire J. Andrew , Arai Andrew E.
Published: January 2008

ACUT2E TSE‐SSFP is a hybrid between steady state free precession (SSFP) and turbo spin echo (TSE) for bright‐blood T2‐weighted imaging with signal‐to‐noise ratio (SNR) and contrast‐to‐noise ratio (CNR) similar to dark‐blood TSE. TSE‐SSFP uses a segmented SSFP readout during diastole with 180° pulses following a 90° preparation. The 180° refocusing pulses make TSE‐SSFP similar to TSE but TSE‐SSFP uses gradient moment nulling, whereas TSE uses gradient crushing. TSE‐SSFP produced T2‐weighted images with minimal T1 weighting. TSE‐SSFP and TSE had similar SNR (155.9 ± 6.0 vs 160.9 ± 7.0; P = NS) for acute myocardial infarction (MI) and twice the SNR of T2‐prepared SSFP (73.1 ± 3.4, P < 0.001). TSE‐SSFP and TSE had approximately double the CNR of T2‐prepared SSFP for differentiating acute MI from normal myocardium. Imperfect blood suppression, present in all animals on some TSE images, was a problem eliminated by TSE‐SSFP and T2‐prepared SSFP. Magn Reson Med 59:229–235, 2008. © 2008 Wiley‐Liss, Inc.
Numerical simulation of bolt‐supported tunnels by means of a multiphase model conceived as an improved homogenization procedure
Authors: de Buhan Patrick , Bourgeois Emmanuel , Hassen Ghazi
Published: January 2008

This paper examines the possibility of applying a homogenization procedure to analyze the convergence of a tunnel reinforced by bolts, regarded as periodically distributed linear inclusions. Owing to the fact that a classical homogenization method fails to account for the interactions prevailing between the bolts and the surrounding ground and thus tends to significantly overestimate the reinforcement effect in terms of convergence reduction, a so‐called multiphase model is presented and developed, aimed at improving the classical homogenization method. Indeed, according to this model, the bolt‐reinforced ground is represented at the macroscopic scale as the superposition of two mutually interacting continuous phases, describing the ground and the reinforcement network, respectively. It is shown that such a multiphase approach can be interpreted as an extension of the homogenization procedure, thus making it possible to capture the ground–reinforcement interaction in a proper way, provided the constitutive parameters of the model and notably those relating to the interaction law can be identified from the reinforced ground characteristics. The numerical implementation of this model in a finite element method‐based computer code is then carried out, and a first illustrative application is finally presented. Copyright © 2008 John Wiley & Sons, Ltd.
Lack of interleukin‐4 receptor α chain‐dependent signalling promotes azoxymethane‐induced colorectal aberrant crypt focus formation in Balb/c mice
Authors: Ko CWS , Cuthbert RJ , Orsi NM , Brooke DA , Perry SL , Markham AF , Coletta PL , Hull MA
Published: January 2008

Interleukin (IL)‐4 receptor (IL‐4R) α chain‐dependent signalling by IL‐4 and IL‐13 promotes tumour growth and metastasis in mouse models of colorectal cancer. However, the role of IL‐4Rα‐dependent signalling during the early, pre‐malignant stages of colorectal carcinogenesis has not been investigated. Therefore, we investigated the effect of deletion of the IL‐4Rα gene on azoxymethane‐induced colorectal aberrant crypt focus (ACF) multiplicity and size in Balb/c mice. IL‐4Rα−/− mice developed significantly more ACFs [median 8, inter‐quartile range (IQR) 4–11.5; n = 9] than wild‐type (WT) animals (median 4, IQR 1–6; n = 9; p = 0.04, Mann–Whitney U‐test). There were significantly higher levels of IL‐4 in serum from azoxymethane‐ and sham‐treated IL‐4Rα−/− mice than WT animals, but no difference in serum IL‐13 levels. In the absence of functional IL‐4Rs, IL‐13 can also signal via the IL‐13Rα2 receptor, leading to induction of transforming growth factor (TGF) β, which has pro‐tumourigenic activity at early stages of intestinal tumourigenesis. We found that mucosal TGFβ mRNA levels and intestinal epithelial cell TGFβ immunoreactivity were significantly higher in IL‐4Rα−/− mice than inWT animals. In summary, IL‐4Rα‐dependent signalling has a protective, anti‐neoplastic role during the post‐initiation phase of azoxymethane‐induced colorectal carcinogenesis in Balb/c mice. Our data should prompt thorough investigation of the role of IL‐4Rα‐dependent signalling during human colorectal carcinogenesis, particularly as antagonism of IL‐4R signalling represents a therapeutic strategy for asthma and other allergic diseases. Copyright © 2008 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
Statistical copolymers of 2‐(trimethylsilyloxy)ethyl methacrylate and methyl methacrylate synthesized by ATRP
Authors: Ritz Pavel , Látalová Petra , Kříž Jaroslav , Genzer Jan , Vlček Petr
Published: January 2008

No Abtract.
Weed species shifts in glyphosate‐resistant crops
Authors: Owen Micheal DK
Published: January 2008

The adoption of glyphosate‐based crop production systems has been one of the most important revolutions in the history of agriculture. Changes in weed communities owing to species that do not respond to current glyphosate‐based management tactics are rapidly increasing. Clearly, glyphosate‐resistant crops (GRCs) do not influence weeds any more than non‐transgenic crops. For most crops, the trait itself is essentially benign in the environment. Rather, the weed control tactics imposed by growers create the ecological selection pressure that ultimately changes the weed communities. This is seen in the adoption of conservation tillage and weed management programs that focus on one herbicide mode of action and have hastened several important weed population shifts. Tillage (disturbance) is one of the primary factors that affect changes in weed communities. The intense selection pressure from herbicide use will result in the evolution of herbicide‐resistant weed biotypes or shifts in the relative prominence of one weed species in the weed community. Changes in weed communities are inevitable and an intrinsic consequence of growing crops over time. The glyphosate‐based weed management tactics used in GRCs impose the selection pressure that supports weed population shifts. Examples of weed population shifts in GRCs include common waterhemp [Amaranthus tuberculatus (Moq ex DC) JD Sauer], horseweed (Conyza canadensis L), giant ragweed (Ambrosia trifida L) and other relatively new weed problems. Growers have handled these weed population shifts with varying success depending on the crop. Copyright © 2008 Society of Chemical Industry
Kinetic studies on aminopeptidase M‐mediated degradation of human hemorphin LVV‐H7 and its N‐terminally truncated products
Authors: John Harald , John Stefanie , Forssmann Wolf‐Georg
Published: January 2008

The human hemorphin LVV‐H7 belongs to the class of µ‐opiod receptor‐binding peptides, which also exhibits significant affinity to insulin‐regulated aminopeptidase (IRAP) thereby affecting IRAP inhibition. The inhibitory potency towards IRAP is of pharmaceutical interest for the treatment of Alzheimer's disease. Consecutive N‐terminal cleavage of the first two amino acid residues of LVV‐H7 affects a drastic increase of the binding affinity (V‐H7) but ultimately leads to its complete abolition after cleavage of the next amino acid residue (H7). Therefore, we investigated LVV‐H7 truncation by aminopeptidase M (AP‐M) identified as a LVV‐H7 degrading enzyme potentially regulating hemorphin activity towards IRAP in vivo. Using a selective quantitative multi‐component capillary zone electrophoretic method (CZE‐UV), we analyzed the AP‐M‐mediated subsequent proteolysis of the hemorphins LVV‐H7 (L32‐F41), VV‐H7 (V33‐F41), and V‐H7 (V34‐F41) in vitro. Incubations were carried out with synthetic hemorphins applied as single substrates or in combination. Maximum velocities (Vmax), catalytic constants (turnover numbers, kcat), and specific enzyme activities (EA) were calculated. L32 cleavage from LVV‐H7 happens more than two‐times faster (kcat: 140 min−1 ± 9%, EA: 1.0 U/mg ± 9%) than V33 cleavage from VV‐H7 (kcat: 61 min−1 ± 10%, EA: 0.43 U/mg ± 10%) or V32 deletion from V‐H7 (kcat: 62 min−1 ± 8%, EA: 0.46 U/mg ± 8%). In contrast, we showed that H7 (Y35‐F41) was neither degraded by porcine AP‐M nor did it act as an inhibitor for this enzyme. Determined turnover numbers were in the same dimension as those reported for dynorphin degradation. This is the first time that AP‐M‐mediated truncation of natural underivatized LVV‐H7 and its physiological metabolites was analyzed to determine kinetic parameters useful for understanding hemorphin processing and designing hemorphin‐derived drug candidates. Copyright © 2008 European Peptide Society and John Wiley & Sons, Ltd.
Discovery of new analogs of the marine biotoxin azaspiracid in blue mussels (Mytilus edulis) by ultra‐performance liquid chromatography/tandem mass spectrometry
Authors: Rehmann Nils , Hess Philipp , Quilliam Michael A.
Published: January 2008

Azaspiracids (AZAs) are a group of lipophilic marine biotoxins that were first discovered in blue mussels harvested in 1995 in Killary Harbour on the west coast of Ireland. At least eight people fell ill after the consumption of contaminated mussels and developed symptoms of nausea, stomach cramps, vomiting and severe diarrhoea. Until now, eleven different analogs of these toxins have been described, with a twelfth one theoretically postulated. This paper describes the detection and identification of twenty new analogs of azaspiracid, including dihydroxy‐AZAs and carboxy‐AZAs, using state‐of‐the‐art techniques including ultra‐performance liquid chromatography (UPLC) and tandem mass spectrometry (MS/MS). Blue mussels (Mytilus edulis) from a toxic event of the northwest coast of Ireland in 2005 were extracted and analysed using LC/MS. The mass spectra obtained from different instruments enabled identification of previously unknown analogs of azaspiracid with additional hydroxyl and carboxyl substituents. Mass fragmentation patterns of the dihydroxy‐AZAs indicated the positions of these substituents to be at the C3 and C23 position. The previously theoretically postulated AZA12 was also observed in this study. Product ion spectra showed the presence of a unique fragment ion at m/z 408 for all C23‐hydroxylated analogs. This fragmentation competes with the fragmentation leading to m/z 362, a fragment ion that has shown to be present in all AZAs. The novel analogs have not been seen in plankton or water samples and are believed to be metabolites of AZAs formed in mussels. All the new AZA analogs were present at low concentrations in the shellfish and it is probably safe to assume that they do not pose a risk for the shellfish consumer. Copyright © 2008 John Wiley & Sons, Ltd. and Crown in the right of Canada
Quantification of human insulin‐like growth factor‐1 and qualitative detection of its analogues in plasma using liquid chromatography/electrospray ionisation tandem mass spectrometry
Authors: Bredehöft Michael , Schänzer Wilhelm , Thevis Mario
Published: January 2008

Human insulin‐like growth factor‐1 (IGF‐1) is a peptide hormone that acts as a mediator of most of the somatotropic effects of growth hormone (GH). Therefore, it is supposed to be a biomarker indicating GH abuse in sports as well as diseases associated with a change in IGF‐1 plasma concentration. It can be applied locally by injection to increase total protein and DNA content in tissues such as skeletal muscle – a highly desirable effect in various sports disciplines. In order to improve its growth‐promoting properties, the primary structure of IGF‐1 has been modified, yielding analogues such as des(1‐3)IGF‐1 and LONG™R3IGF‐1, which show a considerably reduced affinity to the respective binding proteins in plasma and, thus, an increased bioavailability at target tissues. Due to their capability to enhance performance, IGF‐1 and its analogues belong to the prohibited list of the World Anti‐Doping Agency. Hence, it was necessary to develop a reliable assay for the quantification of human IGF‐1 as well as the detection of its derivatives. Immunoaffinity isolation and purification from 60 µL of plasma followed by liquid chromatography/electrospray ionisation tandem mass spectrometry enabled the unequivocal determination of all target analytes. Diagnostic product ions were characterised utilising an Orbitrap mass spectrometer with high resolution/high accuracy properties and employed for triple quadrupole MS/MS analysis. The described assay provided lower limits of detection (LLODs) between 20 and 50 ng/mL, recovery rates between 34–43% and a precision <15% at the LLOD as well as higher concentration levels. In order to prove the applicability of the developed assay, human plasma samples were analysed and the results were compared with the values obtained from a commercially available immunoradiometric assay (IRMA). Four of six samples resulted in concentration ratios with good correlation between both assays, whereas the absolute concentrations were lower for the presented procedure. Copyright © 2008 John Wiley & Sons, Ltd.
Analysis of polycyclic aromatic hydrocarbon sequences in a premixed laminar flame by on‐line time‐of‐flight mass spectrometry
Authors: Panariello Marina , Apicella Barbara , Armenante Mario , Bruno Annalisa , Ciajolo Anna , Spinelli Nicola
Published: January 2008

A time‐of‐flight mass spectrometer in reflectron configuration has been used for the real‐time detection of combustion products. The products of a premixed laminar C2H4/O2 flame at atmospheric pressure were sampled along its axis, diluted with inert gas and carried to the ion source as a molecular beam under minimal perturbation. Electron ionization and different optical ionization sources are compared. Photoionization was achieved with laser radiation from a Nd:YAG nanosecond pulsed laser at two different wavelengths in the UV range (266 and 355 nm). The mass spectra obtained using laser wavelength of 355 nm and electron ionization present a series of ions regularly spaced by 18 m/z units up to m/z 2000. This series allowed precise calibration of the instrument for compounds of high molecular weight. Information on the chemical nature of the analyzed species has been obtained by comparing mass spectra produced with different ionization methods. In order to better understand the growth mechanisms, polycyclic aromatic hydrocarbon sequences have been analyzed by fast Fourier transform of the mass spectra. Copyright © 2008 John Wiley & Sons, Ltd.
An investigation of the distribution of minor components in complex polymeric paint formulations using ToF‐SIMS depth profiling
Authors: Hinder Steven J. , Watts John F. , Simmons Garnett C. , Lowe Chris
Published: January 2008

A series of complex polymeric paint formulations have been investigated by ToF‐SIMS depth profiling. Employing a Bin+ analysis source and a Buckminster Fullerene (C60) etch source in the dual‐beam mode of operation, depth profiles from poly(vinylidene difluoride) (PVdF), poly(urethane) (PU), polyester (PE) and epoxy‐based commercial coatings were obtained to determine the distribution of minor components included in the coating formulation.

The addition of small quantities of additives such as flow agents is known to induce significant changes in the surface composition of the paint. Depth profiles were obtained from a PU primer formulation to which a 35Cl/37Cl labelled flow agent had been added. The depth profiles show that the chlorine tagged component is confined to the surface region of the coating due to segregation of the flow agent to the air/coating surface. Depth profiles obtained from a PVdF topcoat formulation that included a hexamethoxymethyl melamine (HMMM) cross‐linking agent demonstrate that the HMMM intensity is greater at the coating surface than in the bulk. The HMMM depth profile also reveals that the HMMM possesses a depletion zone between the coating bulk and the air/coating surface. Depth profiles obtained from both PE and epoxy primer formulations show that the concentration of inorganic particles included as pigments and anti‐corrosion agents in the coatings is greater in the coating bulk than at the coating surface, demonstrating effective detection of these second phase particles, and that, as expected, they are properly dispersed in the organic phase. The results demonstrate that depth profiling of polymeric coatings, when employing a C60 etch source, can be used to determine the distribution of minor components within cured coatings. Copyright © 2008 John Wiley & Sons, Ltd.
Evaluation of an ultra‐wide bandwidth wireless indoor non‐line‐of‐sight channels
Authors: Wang Yang , Zhang Jie , Zhang Qinyu , Zhang Naitong
Published: January 2008

In this paper, based on the analysis of the experimental data using a new post‐processing method for time‐domain channel measurements, a new double‐cluster statistical model for UWB systems with a bandwidth lower than 1 GHz in non‐line‐of‐sight (NLOS) indoor propagation environment is proposed. By using the proposed model, both the model itself and the parameter estimation of the corresponding model are simplified. By defining the polarity of a particular model parameter, the model has the flexibility to deal with both ‘soft NLOS’ and ‘hard NLOS’ indoor propagation environments. Therefore, the channel impulse responses (CIRs) generated by the proposed model ‘resemble’ the measured CIR better than the SV (Saleh‐‐Valenzuela)/IEEE 802.15.3a model not only in terms of the average values, but also in terms of the cumulative distribution functions (CDFs) of the small‐scale statistics. Copyright © 2008 John Wiley & Sons, Ltd.