bluuebunny/crossref_metadata_2025 huggingface dataset:
Differential immunogenicity and allergenicity of native and recombinant human lactoferrins: Role of glycosylation
Authors: Almond Rachael J. , Flanagan Brian F. , Antonopoulos Aristotelis , Haslam Stuart M. , Dell Anne , Kimber Ian , Dearman Rebecca J.
Published: September 2012

Human native milk lactoferrin (LF) and recombinant forms of lactoferrin (rLF) are available with identical aa sequences, but different glycosylation patterns. Native lactoferrin (NLF) possesses the intrinsic ability to stimulate vigorous IgG and IgE antibody responses in BALB/c mice, whereas recombinant forms (Aspergillus or rice) are 40‐fold less immunogenic and 200‐fold less allergenic. Such differences are independent of endotoxin or iron content and the glycans do not contribute to epitope formation. A complex glycoprofile is observed for NLF, including sialic acid, fucose, mannose, and Lewis (Le)x structures, whereas both rLF species display a simpler glycoprofile rich in mannose. Although Lex type sugars play a Th2‐type adjuvant role, endogenous expression of Lex on NLF did not completely account for the more vigorous IgE responses it provoked. Furthermore, coadminstration of rLF downregulated IgE and upregulated IgG2a antibody responses provoked by NLF, but was without effect on responses to unrelated peanut and chicken egg allergens. These results suggest glycans on rLF impact the induction phase to selectively inhibit IgE responses and that differential glycosylation patterns may impact on antigen uptake, processing and/or presentation, and the balance between Th1 and Th2 responses.
Phosphate‐Based Organic Molecules Interleaved with Layered Double Hydroxide: Unraveling the Roles of Host Cations and the Guest‐Inhibiting Effect in Aluminum Corrosion Protection
Authors: Stimpfling Thomas , Leroux Fabrice , Hintze‐Bruening Horst
Published: September 2012

The incorporation of 2‐hydroxyethyl phosphate (2‐HEP) into layered double hydroxide (LDH) galleries results in the formation of new organic–inorganic hybrid assemblies, subsequently studied as a functionalized filler with regards to their corrosion inhibition as an epoxy‐based polymer primer coating of aluminum AA 2024. Hybrid layered assemblies as well as the concomitant conveivable processes that consist of the release of interleaved 2‐HEP and the uptake of corrosive Cl– anions were studied by X‐ray diffraction. From DC polarization experiments, it is demonstrated that the anodic corrosion inhibition of 2‐HEP is not impeded when the molecule is intercalated in the LDH container despite the absence of its release through anion exchange. Owing to the relatively low anticorrosive activity of 2‐HEP, the importance of the dissolution of the platelets over the course of the anodic corrosion process is uncovered in addition to the impact of the particles on barrier effects. In accordance with discussed anticorrosive mechanisms, the results reveal that the Mg2+‐based LDH host accelerates cathodic oxygen reduction, whereas the Zn2+‐based counterpart reduces anodic metal (or copper) dissolution. Additionally, through electrochemical impedance spectroscopy that probes the coating resistance after long immersion times, Zn2Al/2‐HEP hybrid LDH phase was found to perform as well as a chromate‐bearing LDH.
Synthesis and Structuring of Ni MoS2 by using an Ionic Liquid
Authors: Leyral Géraldine , Ribes Michel , Courthéoux Laurence , Uzio Denis , Pradel Annie
Published: September 2012

To minimize air pollution resulting from exhaust gas emission, a decrease in the concentrations of the sulfur compounds in fuels has become a major issue in the last 10 years. The development of catalysts for the hydrodesulfurization process is a challenge for the oil industry. In the present work, a new and easy way to synthesize Ni‐Mo‐S hydrotreatment catalysts and in particular the effect of ionic liquids on the final structure was studied. It was shown that the addition of the ionic liquid [BMIM][NTf2] to the main reactants [Ni(NO3)2·6H2O and (NH4)2MoS4] had a great impact on the final product morphology. Indeed, formation of nanoparticles instead of gel was observed, and the amount of ionic liquid introduced helped to control the shape and size of the particles. Moreover, it was also highlighted that the presence of an ionic liquid favored the promotion of MoS2 with Ni with an optimal Ni/(Ni+Mo) atomic ratio of 0.3, and it also impacted the nanostructure, leading to thinner and shorter MoS2 slabs, which are two attractive points for catalytic applications.
Oxidative Carbonylation as a Powerful Tool for the Direct Synthesis of Carbonylated Heterocycles
Authors: Gabriele Bartolo , Mancuso Raffaella , Salerno Giuseppe
Published: September 2012

Recent advances in the field of oxidative carbonylation reactions leading to carbonylated heterocyclic derivatives are presented (coverage: 2006 to the beginning of 2012).
Organocatalyzed Intramolecular Michael Addition of Morita–Baylis–Hillman Adducts of β‐Arylnitroethylenes: An Entry to 3‐Aryl‐4‐nitrocyclohexanones
Authors: Raji Reddy Chada , Reddy Motatipally Damoder , Haribabu Kothapalli
Published: September 2012

The synthesis of 3‐aryl‐4‐nitrocyclohexanones has been achieved from the Morita–Baylis–Hillman adducts of β‐arylnitroethylenes. The strategy involves proline‐catalyzed diastereoselective intramolecular Michael addition to obtain 3,4‐trans‐disubstituted cyclohexanones. This method provides a facile access to (±)‐epibatidine analogues.
Mild Chemical and Biological Synthesis of Donor–Acceptor Flanked Reporter Stilbenes: Demonstration of a Physiological Wittig Olefination Reaction
Authors: McLeod David , McNulty James
Published: September 2012

Unprecedented chemoselectivity is reported for the Wittig olefination reaction leading to the formation of reporter stilbenes under physiological conditions.
Discretionary and transactional human resource practices and employee outcomes: The role of perceived organizational support
Authors: Gavino Monica C. , Wayne Sandy J. , Erdogan Berrin
Published: September 2012

Utilizing perceived organizational support (POS) as the mechanism linking HR practices to employee behaviors in the workplace, we examine a broad set of HR practices in order to understand the relative importance of each HR practice (i.e., those that explain incremental variance over other practices) in influencing employee behaviors. We differentiate between discretionary and transactional HR practices to test the discretionary investment requisite of POS theory. The results show that of the eight discretionary practices, only participation and decision making directly influenced the extra‐role behaviors that employees exhibit, and only training and development directly impacted the customer‐oriented behaviors. Furthermore, one of the transactional HR practices was found to have a direct effect on organizational citizenship behavior. Our findings indicate that the performance management process, promotional opportunities, participation, and involvement in decision making affect how employees behave toward the customer and the extra‐role behaviors they exhibit. Furthermore, this occurs through the view employees develop of the organization as a place to work. That is, these four HR practices demonstrate to employees that they are valued, and, in turn, this feeling of being appreciated impacts their commitment to delivering high‐quality service to the customer and going beyond their job responsibilities. Implications for research and practice are discussed. © 2012 Wiley Periodicals, Inc.
Performance implications of knowledge and competitive arousal in times of employee mobility: “The immutable law of the ex”
Authors: Pazzaglia Federica , Flynn Scott , Sonpar Karan
Published: September 2012

This article elaborates on extant literature on employee mobility by focusing on how the movement of personnel between competitors affects their competitive positions. Our mixed‐methods study of 402 head‐to‐head encounters from the English Premier League (2000–2005) reveals that transferred players improve the performance of the recipient team in head‐to‐head encounters against the donor. We also provide evidence that competitive arousal, as triggered by anger and pressures for proving loyalty to the recipient organization, as well as knowledge of the donor team's routines, explain the superior performance of transferred players. These results question the traditional view that organizational routines are not transferable through employee mobility. They also move beyond a prior emphasis on the negative effects of emotional states such as anger and competitive arousal, highlighting how these can occasionally be beneficial. © 2012 Wiley Periodicals, Inc.
Servant leadership, organizational identification, and work‐to‐family enrichment: The moderating role of work climate for sharing family concerns
Authors: Zhang Haina , Kwong Kwan Ho , Everett André M. , Jian Zhaoquan
Published: September 2012

The present study investigates the impact of servant leadership as perceived by followers on their work‐to‐family enrichment (WFE) by focusing on the mediating role of organizational identification and the moderating role of work climate for sharing family concerns. The results from a field survey of 230 married managers in China provide full support for our hypotheses, indicating that perceived servant leadership is positively related to WFE; this relationship is also mediated by organizational identification. In addition, work climate for sharing family concerns attenuates the effects of servant leadership on organizational identification and WFE. The theoretical and managerial implications of these findings are discussed. © 2012 Wiley Periodicals, Inc.
The social context of performance appraisal and appraisal reactions: A meta‐analysis
Authors: Pichler Shaun
Published: September 2012

This study reviews and meta‐analyzes the literature on the social context of performance appraisal. Results indicate that aspects of rater‐ratee relationship quality (i.e., supervisor satisfaction, supervisor support, supervisor trust) are strongly related to ratee reactions to performance appraisals. Rater‐ratee relationship quality is more strongly related to appraisal reactions than appraisal participation or performance ratings. Integrating social exchange theory with procedural justice theory, this article tested whether or not the relationship quality–appraisal reactions relationship was due to relationships between relationship quality and instrumental resources for the ratee (i.e., appraisal participation and rating favorability). When controlling for relationships between these resources and appraisal reactions, a direct path between relationship quality and reactions was significant, supporting a relational model of the exchange between appraisal partners. The relationship quality–appraisal reaction relationship was not moderated by performance rating favorability or appraisal participation. In total, these results highlight the importance of relationship quality to employee reactions to performance appraisal—and the importance of ratee reactions as an important resource in the social exchange between appraisal partners. Implications for theory, practice, and future research are discussed. © 2012 Wiley Periodicals, Inc.
A Comparative Analysis of Anglo‐Australian Pre‐packs: Can the Means Be Made to Justify the Ends?
Authors: Wellard Mark , Walton Peter
Published: September 2012

Whereas pre‐packaged administrations have been prevalent in the UK for years, Australia's voluntary administration regime has been more restrictive of the practice. This article analyses the evolution of UK pre‐packs, why UK‐style pre‐packs are not prevalent in Australia and the challenges for UK and Australian lawmakers in striking the right balance with pre‐packs in their respective administration regimes. Building upon this analysis, the article proposes a mechanism that might make ‘connected‐party’ pre‐pack business sales work more fairly for stakeholders—that is, by obligating a connected‐party purchaser to make a future‐income contribution in favour of the insolvent company whose business has been ‘rescued’ by a pre‐packaged sale in administration. Copyright © 2012 INSOL International and John Wiley & Sons, Ltd.
Protein predictive signatures for lymph node metastasis of gastric cancer
Authors: Li Wei , Ye Fei , Wang Daguang , Sun Xuan , Tong Weihua , Lian Guodong , Jiang Jing , Suo Jian , Zhang David Y.
Published: September 2012

Lymph node status remains one of most crucial indicators of gastric cancer prognosis and treatment planning. Current imaging methods have limited accuracy in predicting lymph node metastasis. We sought to identify protein markers in primary gastric cancer and to define a risk model to predict lymph node metastasis. The Protein Pathway Array (PPA) (initial selection) and Western blot (confirmation) were used to assess the protein expression in a total of 190 freshly frozen gastric cancer samples. The protein expression levels were compared between samples with lymph node metastasis (n = 73) and those without lymph node metastasis (n = 57) using PPA. There were 27 proteins differentially expressed between lymph node positive samples and lymph node negative samples. Five proteins (Factor XIII B, TFIIH p89, ADAM8, COX‐2 and CUL‐1) were identified as independent predictors of lymph node metastasis. Together with vascular/lymphatic invasion status, a risk score model was established to determine the risk of lymph node metastasis for each individual gastric cancer patient. The ability of this model to predict lymph node metastasis was further confirmed in a second cohort of gastric cancer patients (33 with and 27 without lymph node metastasis) using Western blot. This study indicated that some proteins differentially expressed in gastric cancer can be selected as clinically useful biomarkers. The risk score model is useful for determining patients' risk of lymph node metastasis and prognosis.
Early Postpartum Parental Preoccupation and Positive Parenting Thoughts: Relationship with Parent–Infant Interaction
Authors: Kim Pilyoung , Mayes Linda , Feldman Ruth , Leckman James F. , Swain James E.
Published: September 2012

Parenting behaviors and parent–infant emotional bonding during the early postpartum months play a critical role in infant development. However, the nature and progression of parental thoughts and their relationship with interactive behaviors have received less research. The current study investigated the trajectory of parental thoughts and behaviors among primiparous mothers (n = 18) and fathers (n = 15) and multiparous mothers (n = 13) and fathers (n = 13), which were measured at the first and third postpartum month. At the third postpartum month, the relationship between parental thoughts and parental interactive behaviors also was tested. Mothers and fathers showed high levels of preoccupations and caregiving thoughts during the first postpartum month that significantly declined by the third postpartum month. In contrast, positive thoughts about parenting and the infant increased over the same time interval. Mothers presented higher levels of preoccupations and positive thoughts than did fathers, and first‐time parents reported more intense preoccupations than did experienced parents. Although maternal sensitivity was inversely related to maternal anxious thoughts, paternal sensitivity was predicted by higher levels of anxious as well as caregiving and positive thoughts.
Surface modification of Thai silk fibroin scaffolds with gelatin and chitooligosaccharide for enhanced osteogenic differentiation of bone marrow‐derived mesenchymal stem cells
Authors: Wongputtaraksa Tanom , Ratanavaraporn Juthamas , Pichyangkura Rath , Damrongsakkul Siriporn
Published: September 2012

In this study, the surface modification of silk fibroin (SF) scaffolds with gelatin/chitooligosaccharide (G/COS) blends using the reaction of glutaraldehyde (GA) was established. The effects of G/COS mixing ratio (100/0, 90/10, 80/20, and 70/30) and GA crosslinking concentration (0.05, 0.10, 0.15, and 0.20 vol %) on the properties of scaffolds were investigated. At 0.10–0.20 vol % GA, all G/COS blends could be successfully conjugated on the SF scaffolds, as confirmed by the percentage of weight increased and the presence of functional groups indicating SF, G, and COS from FTIR spectra. Pore size of SF scaffolds was around 570 μm with 92% porosity, however, the G/COS‐conjugated SF scaffolds showed thickened pore's wall, smaller pore size (∼184–275 μm) and less porosity (∼81%), but increased density. This modified structure subsequently improved the compressive modulus of the G/COS‐conjugated SF scaffolds. In terms of biological properties, the gelatin‐conjugated SF scaffolds promoted the attachment and proliferation of bone marrow‐derived mesenchymal stem cells (MSC) rather than the other scaffolds. However, the G/COS‐conjugated SF scaffolds, particularly at the ratio of 70/30, promoted the osteogenic differentiation of MSC comparing to the SF scaffold, as confirmed by the production of alkaline phosphatase (ALP) activity and calcium (Ca), and the deposition of calcium phosphate (CaP). It was concluded that the G/COS‐conjugated SF scaffolds showed great mechanical properties due to the β‐structure of silk fibroin, as well as the enhanced biological properties due to the G/COS blends. © 2012 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2012.
Association between survival in patients with primary invasive breast cancer and computer aided MRI
Authors: Dietzel Matthias , Zoubi Ramy , Vag Tibor , Gajda Mieczyslaw , Runnebaum Ingo B. , Kaiser Werner A. , Baltzer Pascal A.
Published: September 2012

Purpose:

To identify the potential of semi‐quantitative enhancement‐analysis in breast MRI to predict disease‐related death in primary breast cancer patients.

Materials and Methods:

The present study was planned and conducted according to international recommendations. All patients referred for pretherapeutic staging of primary breast cancer during 24 consecutive months were included into the study collective. They were followed‐up by our multidisciplinary breast center. For semi‐quantitative MRI‐analysis dedicated CAD‐software (computer assisted diagnosis) was used. Association between enhancement parameters and disease‐related survival was investigated using Cox proportional‐hazards ‐regression (CR).

Results:

A total of 115 patients were eligible for CR analysis. Median follow‐up time was 52 months. In 15 patients, disease‐related death occurred. CR analysis identified four enhancement parameters as independent and significant (P < 0.001) predictors of the endpoint. Coefficients were “Initial enhancement” (B = 0.0166), “Time to peak‐enhancement” (B = 1.0573), “Tumor volume” (B = 0.0175), and proportion of “tumor volume” showing “slow initial enhancement” followed by a “persistent” curve‐type (B = −0.0586).

Conclusion:

This study demonstrates the significant relationship between semi‐quantitative enhancement analysis in breast MRI and disease‐related death of breast cancer patients. As results were extracted from a routine staging examination, MRI noninvasively provides not only diagnostic information but also outcome data at one step. Future studies should address the impact of these findings on patient management and therapeutic approach. J. Magn. Reson. Imaging 2013;37:146–155. © 2012 Wiley Periodicals, Inc.
Automatic intra‐subject registration‐based segmentation of abdominal fat from water–fat MRI
Authors: Joshi Anand A. , Hu Houchun H. , Leahy Richard M. , Goran Michael I. , Nayak Krishna S.
Published: September 2012

Purpose:

To develop an automatic registration‐based segmentation algorithm for measuring abdominal adipose tissue depot volumes and organ fat fraction content from three‐dimensional (3D) water–fat MRI data, and to evaluate its performance against manual segmentation.

Materials and Methods:

Data were obtained from 11 subjects at two time points with intermediate repositioning, and from four subjects before and after a meal with repositioning. Imaging was performed on a 3 Tesla MRI, using the IDEAL chemical‐shift water–fat pulse sequence. Adipose tissue (subcutaneous—SAT, visceral—VAT) and organs (liver, pancreas) were manually segmented twice for each scan by a single trained observer. Automated segmentations of each subject's second scan were generated using a nonrigid volume registration algorithm for water–fat MRI images that used a b‐spline basis for deformation and minimized image dissimilarity after the deformation. Manual and automated segmentations were compared using Dice coefficients and linear regression of SAT and VAT volumes, organ volumes, and hepatic and pancreatic fat fractions (HFF, PFF).

Results:

Manual segmentations from the 11 repositioned subjects exhibited strong repeatability and set performance benchmarks. The average Dice coefficients were 0.9747 (SAT), 0.9424 (VAT), 0.9404 (liver), and 0.8205 (pancreas); the linear correlation coefficients were 0.9994 (SAT volume), 0.9974 (VAT volume), 0.9885 (liver volume), 0.9782 (pancreas volume), 0.9996 (HFF), and 0.9660 (PFF). When comparing manual and automated segmentations, the average Dice coefficients were 0.9043 (SAT volume), 0.8235 (VAT), 0.8942 (liver), and 0.7168 (pancreas); the linear correlation coefficients were 0.9493 (SAT volume), 0.9982 (VAT volume), 0.9326 (liver volume), 0.8876 (pancreas volume), 0.9972 (HFF), and 0.8617 (PFF). In the four pre‐ and post‐prandial subjects, the Dice coefficients were 0.9024 (SAT), 0.7781 (VAT), 0.8799 (liver), and 0.5179 (pancreas); the linear correlation coefficients were 0.9889, 0.9902 (SAT, and VAT volume), 0.9523 (liver volume), 0.8760 (pancreas volume), 0.9991 (HFF), and 0.6338 (PFF).

Conclusion:

Automated intra‐subject registration‐based segmentation is potentially suitable for the quantification of abdominal and organ fat and achieves comparable quantitative endpoints with respect to manual segmentation. J. Magn. Reson. Imaging 2013;37:423–430. © 2012 Wiley Periodicals, Inc.
Auto‐Threshold quantification of late gadolinium enhancement in patients with acute heart disease
Authors: Vermes Emmanuelle , Childs Helene , Carbone Iacopo , Barckow Philipp , Friedrich Matthias G.
Published: September 2012

Purpose:

To assess the Otsu‐Auto‐Threshold (OAT) for accuracy and reproducibility for sizing irreversible injury in late gadolinium enhancement (LGE) images of patients with acute heart disease. The OAT method automatically identifies high signal intensity areas using a cutoff derived from the signal intensity histogram and therefore is user‐independent.

Materials and Methods:

LGE was performed in 28 patients with acute myocardial infarction (MI) and 30 patients with acute myocarditis. LGE mass was compared between OAT and thresholds using 2 standard deviations (SD), 3SD, and 5SD above remote myocardium, and full‐width‐at‐half‐maximum (FWHM). A separate, blinded visual assessment served as the standard of truth.

Results:

In patients with acute MI, OAT and 5SD did not differ (26.1 ± 11.4 g vs. 25.4 ± 11.1 g, P = 0.088), but thresholds of 2SD and 3SD overestimated LGE mass by 37% and 20%, respectively, and FWHM underestimated by 15%. In acute myocarditis, OAT was not different from a visual quantification, but thresholds of 2SD and 3SD overestimated LGE mass by 46% and 19%, respectively, and thresholds of 5SD and FWHM underestimated LGE mass by 17% and 26%, respectively. OAT and FWHM showed the best intraobserver and interobserver reproducibility.

Conclusion:

Automatic thresholding using OAT may serve as an accurate and reproducible method to quantify irreversible myocardial injury in acute heart disease. J. Magn. Reson. Imaging 2013;37:382–390. © 2012 Wiley Periodicals, Inc.
Functional MRI of the thoracic spinal cord during vibration sensation
Authors: Kornelsen Jennifer , Smith Stephen D. , McIver Theresa A. , Sboto‐Frankenstein Uta , Latta Peter , Tomanek Boguslaw
Published: September 2012

Purpose:

To demonstrate that it is possible to acquire accurate functional magnetic resonance images from thoracic spinal cord neurons.

Materials and Methods:

The lower thoracic spinal dermatomes (T7–T11) on the right side of the body were mechanically stimulated by vibration for 15 participants. Neuronal responses to vibration sensation were measured in the thoracic spinal cord using a HASTE sequence on a 3 Tesla MRI system.

Results:

Signal increases were observed in the corresponding lower thoracic spinal cord segments ipsilateral to the side of stimulation in the dorsal aspect of the spinal cord.

Conclusion:

This is the first study to provide proof of principle that functional imaging of the entire thoracic spinal cord is possible, by detecting neuronal activity in the thoracic spinal cord during sensory stimulation using spinal fMRI. J. Magn. Reson. Imaging 2013;37:981–985. © 2012 Wiley Periodicals, Inc.
Contrast‐enhanced specific absorption rate‐efficient 3D cardiac cine with respiratory‐triggered radiofrequency gating
Authors: Henningsson Markus , Chan Raymond H. , Goddu Beth , Goepfert Lois A. , Razavi Reza , Botnar Rene M. , Schaeffter Tobias , Nezafat Reza
Published: September 2012

Purpose:

To investigate the use of radiofrequency (RF) gating in conjunction with a paramagnetic contrast agent to reduce the specific absorption rate (SAR) and increase the blood‐myocardium contrast in balanced steady‐state free precession (bSSFP) 3D cardiac cine.

Materials and Methods:

RF gating was implemented by synchronizing the RF‐excitation with an external respiratory sensor (bellows), which could additionally be used for respiratory gating. For reference, respiratory‐gated 3D cine images were acquired without RF gating. Free‐breathing 3D cine images were acquired in eight healthy subjects before and after contrast injection (Gd‐BOPTA) and compared to breath‐hold 2D cine.

Results:

RF‐gated 3D cine reduced the SAR by nearly 40% without introducing significant artifacts while providing left ventricle (LV) measurements similar to those obtained with 2D cine. The contrast‐to‐noise ratio (CNR) was significantly higher for 3D cine compared to 2D cine, both before and after contrast injection; however, no statistically significant CNR increase was observed for the postcontrast 3D cine compared to the precontrast acquisitions.

Conclusion:

Respiratory‐triggered RF gating significantly reduces SAR in 3D cine acquisitions, which may enable a more widespread clinical use of 3D cine. Furthermore, CNR of 3D bSSFP cine is higher than of 2D and administration of Gd‐BOPTA does not improve the CNR of 3D cine. J. Magn. Reson. Imaging 2013;37:986–992. © 2012 Wiley Periodicals, Inc.
Synthesis of prebiotic carbohydrates derived from cheese whey permeate by a combined process of isomerisation and transgalactosylation
Authors: Corzo‐Martínez Marta , Copoví Paula , Olano Agustín , Moreno F Javier , Montilla Antonia
Published: September 2012

Background

Lactose from cheese whey permeate (WP) was efficiently isomerised to lactulose using egg shell, a food‐grade catalyst, and the subsequent transgalactosylation reaction of this mixture with β‐galactosidase from Bacillus circulans gave rise to a wide array of prebiotic carbohydrates derived from lactose and lactulose.

Results

Lactulose obtained by efficient isomerisation of WP (16.1% by weight with respect to the initial amount of lactose) showed great resistance to the hydrolytic action of β‐galactosidase from B. circulans, which preferentially hydrolysed lactose, acting as a galactosyl donor and acceptor. Lactulose had capacity as an acceptor, leading to the formation of lactulose‐derived oligosaccharides. The enzymatic synthesis was optimised by studying reaction conditions such as pH, temperature, time, enzyme concentration and carbohydrate concentration. The maximum formation of galactooligosaccharides with degrees of polymerisation from 2 to 4 was achieved after 5 h of reaction at pH 6.5 and 50 °C with 300 g kg−1 carbohydrates and 3 U mL−1 β‐galactosidase.

Conclusion

These findings indicate that the transgalactosylation of isomerised WP with β‐galactosidase from B. circulans could be a new and efficient method to obtain a mixture with 50% of potentially prebiotic carbohydrates composed of lactulose, and galactooligosaccharides derived from lactose and lactulose.
Magnetically modified spent grain as a low‐cost, biocompatible and smart carrier for enzyme immobilisation
Authors: Pospiskova Kristyna , Safarik Ivo
Published: September 2012

Background

Food and feed technology and biotechnology benefit from the use of immobilised enzymes. New low‐cost enzyme carriers exhibiting high biocompatibility and response to external magnetic field can substantially improve the application potential of immobilised enzyme systems.

Results

Ferrofluid‐modified spent grain was used as a low‐cost, biocompatible and magnetically responsive carrier for the immobilisation of Candida rugosa lipase. Several immobilisation procedures were tested using both native and poly(ethyleneimine)‐modified magnetic spent grain. Activity of immobilised lipase per unit mass of carrier, operational stability, time stability and Michaelis constant were compared. In general, magnetic spent grain modified with poly(ethyleneimine) bound a smaller amount of active lipase than unmodified magnetic spent grain, but the operational and storage stabilities of enzyme immobilised on poly(ethyleneimine)‐modified carrier were very high.

Conclusion

Ferrofluid‐modified spent grain can be a promising low‐cost magnetic carrier for enzyme immobilisation, applicable e.g. in food and feed technology and biotechnology.© 2012 Society of Chemical Industry
Effects of vacuum packing on eggshell microbial activity and egg quality in table eggs under different storage temperatures
Authors: Aygun Ali , Sert Durmus
Published: September 2012

Backround

The aim of this study was to establish the effects of vacuum packing on eggshell microbial activity and egg quality traits in table eggs during 42 days of storage at 5 and 22 °C. Treatments were no vacuum packing (control) and vacuum packing (VP). Egg quality traits measured included egg weight loss, specific gravity, shell strength, albumen height, Haugh unit, yolk index, albumen pH, yolk pH, albumen colour and yolk colour.

Results

VP eggs maintained higher specific gravity, albumen height, Haugh unit and yolk index and lower egg weight loss, albumen pH and yolk pH compared with control eggs after 42 days at 22 °C. VP eggs had lower levels of total aerobic mesophilic bacteria, Salmonella spp., Staphylococcus spp. and moulds/yeasts than control eggs over the storage period at both 5 and 22 °C. However, VP eggs had a higher level of coliforms than control eggs after 42 days at 5 °C.

Conclusion

The results indicated that vacuum packing extended the egg shelf life to at least 42 days compared with control eggs at 5 and 22 °C.
Synthesis of Novel Bis(β‐enaminoketonato)titanium Catalyst with High Activity and Excellent Ability to Copolymerize Olefins
Authors: Yang Guofan , Hong Miao , Li Yuesheng , Yu Shijun
Published: September 2012

A new titanium complex [PhN=C(Ph)CHC(CF3)O]2TiCl2 (2a), with an asymmetric β‐enaminoketonato [N,O] ligand, has been synthesized and fully characterized. With modified methylaluminoxane as a cocatalyst, the behaviors of ethylene polymerization, and ethylene/α‐olefin and ethylene/norbornene copolymerization have been explored in detail. Relative to its regioisomer 2b ([PhN=C(CF3)CHC(Ph)O]2TiCl2), the present catalyst exhibits significant predominance. The catalytic activity in 2a‐catalyzed homo‐ and copolymerization are much higher than those in 2b‐catalyzed (co)polymerization. Furthermore, compared with 2b, catalyst 2a possesses an obviously stronger ability towards copolymerization, due to a wide coordination space caused by exchanging the position of the phenyl group and trifluoromethyl group on the framework.
Providing care to meet complex needs: A cross‐sectorial approach
Authors: Cripps Sue , Spencer Margaret , Clark Andrew
Published: September 2012

This is a case study of a young man with a mild intellectual disability and schizophrenia, who as a result of engaging in high‐risk behaviour acquired HIV and subsequently developed AIDS dementia. This resulted in a crisis of care that could not be resolved by traditional diagnostic based clinical services. A care package was developed by the authors that focused on the young man's needs, while embracing the principles of harm minimisation and the least restrictive environment. The authors argue that it is only through the development of a cross‐sectorial approach based on the needs of the individual that the needs of people with complex care issues can be met.
Parental informed consent in pediatric cancer trials: A population‐based survey in Germany
Authors: Petersen Imme , Spix Claudia , Kaatsch Peter , Graf Norbert , Janka Gritta , Kollek Regine
Published: September 2012

Background

Ensuring adequate parental consent is a key issue of ethical practice in pediatric oncology. In Germany, however, knowledge about parental comprehension and satisfaction with the informed consent procedure is limited, and representative data on parents' perspectives are still missing. Based on data collected by means of a population‐based survey, we evaluated the parental recall of the informed consent process for pediatric clinical trials, and how they rated the consent process retrospectively.

Procedure

A standardized survey was carried out among 1,465 parents whose children were first diagnosed in 2005 with a disease defined by ICCC‐3 in the German Childhood Cancer Registry (response: 55.1%). The survey's primary objective was to assess how well parents were able to recall of the informed consent process. To evaluate the results, we set up a second survey among 581 parents who had given consent recently for their child's participation in a clinical trial (response: 53.5%).

Results

Approximately 81% of the parents in the population‐based survey correctly remembered whether or not their child had been enrolled in a clinical trial or treated off‐trial. The ability to recall accurately is significantly lower if the parents have a migration background or if their child was not a trial participant. However, parents who recalled the child's trial participation status incorrectly felt as adequately informed as parents who recalled it correctly.

Conclusions

Our results identified weak points and vulnerable subgroups in the parental consent process in pediatric oncology in Germany. Pediatr Blood Cancer 2013; 60: 446–450. © 2012 Wiley Periodicals, Inc.
Dicarboxylic acid promoted immortal copolymerization for controllable synthesis of low‐molecular weight oligo(carbonate‐ether) diols with tunable carbonate unit content
Authors: Gao Yonggang , Gu Lin , Qin Yusheng , Wang Xianhong , Wang Fosong
Published: September 2012

Low‐molecular weight oligo(carbonate‐ether) diols are important raw materials for polyurethane formation, which with tunable carbonate unit content (CU) may endow new thermal and mechanical performances to polyurethane. Herein, facile synthesis of oligo(carbonate‐ether) diols with number average molecular weight (Mn) below 2000 g mol−1 and CU tunable between 40% and 75% are realized in high activity by immortal copolymerization of CO2/propylene oxide (PO) using zinc‐cobalt double metal cyanide complex (Zn‐Co‐DMCC) in the presence of sebacic acid (SA). Mn of the oligomer is in good linear relationship to the mole ratio of PO and SA (PO/SA) and hence can be precisely controlled by adjusting PO/SA. Besides, the molecular weight distribution is quite narrow due to the rapid reversible chain transfer in the immortal copolymerization. High pressure and low temperature are favorable for raising CU. In all the reactions, the weight fraction of propylene carbonate (WPC) can even be controlled as low as 2.0 wt %, and the catalytic activity of Zn‐Co‐DMCC is above 1.0 kgg−1 cat. © 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2012
Thaw‐Consolidation Effects on the Stability of Alpine Talus Slopes in Permafrost
Authors: Bommer Christian , Fitze Philipp , Schneider Hansruedi
Published: September 2012

The relative contributions of thaw consolidation and slope‐parallel seepage to the generation of overall porewater pressure and resultant potential changes in slope stability are determined in two case studies of thawing soils. The first study concerns experimental slopes of frozen silt inclined at 12° and 24° that thawed during scaled centrifuge modelling reported by Harris et al. (2008). The second study concerns a natural slope near Pontresina, eastern Swiss Alps, of coarse‐grained talus inclined at 37° and overlying fine‐grained soil that contains the permafrost table. In both cases, seepage parallel to the slope was found to contribute much more to the excess porewater pressures in the thawing soils than did thaw consolidation. This suggests that the effects of thaw consolidation on the stability of alpine talus slopes in mountain permafrost may have only minor significance. Copyright © 2012 John Wiley & Sons, Ltd.
The crystal structure of the Rv0301‐Rv0300 VapBC‐3 toxin—antitoxin complex from M. tuberculosis reveals a Mg2+ ion in the active site and a putative RNA‐binding site
Authors: Min Andrew B. , Miallau Linda , Sawaya Michael R. , Habel Jeff , Cascio Duilio , Eisenberg David
Published: September 2012

VapBC pairs account for 45 out of 88 identified toxin‐antitoxin (TA) pairs in the Mycobacterium tuberculosis (Mtb) H37Rv genome. A working model suggests that under times of stress, antitoxin molecules are degraded, releasing the toxins to slow the metabolism of the cell, which in the case of VapC toxins is via their RNase activity. Otherwise the TA pairs remain bound to their promoters, autoinhibiting transcription. The crystal structure of Rv0301‐Rv0300, an Mtb VapBC TA complex determined at 1.49 Å resolution, suggests a mechanism for these three functions: RNase activity, its inhibition by antitoxin, and its ability to bind promoter DNA. The Rv0301 toxin consists of a core of five parallel beta strands flanked by alpha helices. Three proximal aspartates coordinate a Mg2+ ion forming the putative RNase active site. The Rv0300 antitoxin monomer is extended in structure, consisting of an N‐terminal beta strand followed by four helices. The last two helices wrap around the toxin and terminate near the putative RNase active site, but with different conformations. In one conformation, the C‐terminal arginine interferes with Mg2+ ion coordination, suggesting a mechanism by which the antitoxin can inhibit toxin activity. At the N‐terminus of the antitoxin, two pairs of Ribbon‐Helix‐Helix (RHH) motifs are related by crystallographic twofold symmetry. The resulting hetero‐octameric complex is similar to the FitAB system, but the two RHH motifs are about 30 Å closer together in the Rv0301‐Rv0300 complex, suggesting either a different span of the DNA recognition sequence or a conformational change.
Regulation of the activities of the mammalian transglutaminase family of enzymes
Authors: Klöck Cornelius , Khosla Chaitan
Published: September 2012

Mammalian transglutaminases catalyze post‐translational modifications of glutamine residues on proteins and peptides through transamidation or deamidation reactions. Their catalytic mechanism resembles that of cysteine proteases. In virtually every case, their enzymatic activity is modulated by elaborate strategies including controlled gene expression, allostery, covalent modification, and proteolysis. In this review, we focus on our current knowledge of post‐translational regulation of transglutaminase activity by physiological as well as synthetic allosteric agents. Our discussion will primarily focus on transglutaminase 2, but will also compare and contrast its regulation with Factor XIIIa as well as transglutaminases 1 and 3. Potential structure–function relationships of known mutations in human transglutaminases are analyzed.
Smooth statistical torsion angle potential derived from a large conformational database via adaptive kernel density estimation improves the quality of NMR protein structures
Authors: Bermejo Guillermo A. , Clore G. Marius , Schwieters Charles D.
Published: September 2012

Statistical potentials that embody torsion angle probability densities in databases of high‐quality X‐ray protein structures supplement the incomplete structural information of experimental nuclear magnetic resonance (NMR) datasets. By biasing the conformational search during the course of structure calculation toward highly populated regions in the database, the resulting protein structures display better validation criteria and accuracy. Here, a new statistical torsion angle potential is developed using adaptive kernel density estimation to extract probability densities from a large database of more than 106 quality‐filtered amino acid residues. Incorporated into the Xplor‐NIH software package, the new implementation clearly outperforms an older potential, widely used in NMR structure elucidation, in that it exhibits simultaneously smoother and sharper energy surfaces, and results in protein structures with improved conformation, nonbonded atomic interactions, and accuracy.
Side‐chain hydrophobicity and the stability of Aβ16–22 aggregates
Authors: Berhanu Workalemahu M. , Hansmann Ulrich H. E.
Published: September 2012

Recent mutagenesis studies using the hydrophobic segment of Aβ suggest that aromatic π‐stacking interactions may not be critical for fibril formation. We have tested this conjecture by probing the effect of Leu, Ile, and Ala mutation of the aromatic Phe residues at positions 19 and 20, on the double‐layer hexametric chains of Aβ fragment Aβ16–22 using explicit solvent all‐atom molecular dynamics. As these simulations rely on the accuracy of the utilized force fields, we first evaluated the dynamic and stability dependence on various force fields of small amyloid aggregates. These initial investigations led us to choose AMBER99SB‐ILDN as force field in multiple long molecular dynamics simulations of 100 ns that probe the stability of the wild‐type and mutants oligomers. Single‐point and double‐point mutants confirm that size and hydrophobicity are key for the aggregation and stability of the hydrophobic core region (Aβ16–22). This suggests as a venue for designing Aβ aggregation inhibitors the substitution of residues (especially, Phe 19 and 20) in the hydrophobic region (Aβ16–22) with natural and non‐natural amino acids of similar size and hydrophobicity.
LacZ β‐galactosidase: Structure and function of an enzyme of historical and molecular biological importance
Authors: Juers Douglas H. , Matthews Brian W. , Huber Reuben E.
Published: September 2012

This review provides an overview of the structure, function, and catalytic mechanism of lacZ β‐galactosidase. The protein played a central role in Jacob and Monod's development of the operon model for the regulation of gene expression. Determination of the crystal structure made it possible to understand why deletion of certain residues toward the amino‐terminus not only caused the full enzyme tetramer to dissociate into dimers but also abolished activity. It was also possible to rationalize α‐complementation, in which addition to the inactive dimers of peptides containing the “missing” N‐terminal residues restored catalytic activity. The enzyme is well known to signal its presence by hydrolyzing X‐gal to produce a blue product. That this reaction takes place in crystals of the protein confirms that the X‐ray structure represents an active conformation. Individual tetramers of β‐galactosidase have been measured to catalyze 38,500 ± 900 reactions per minute. Extensive kinetic, biochemical, mutagenic, and crystallographic analyses have made it possible to develop a presumed mechanism of action. Substrate initially binds near the top of the active site but then moves deeper for reaction. The first catalytic step (called galactosylation) is a nucleophilic displacement by Glu537 to form a covalent bond with galactose. This is initiated by proton donation by Glu461. The second displacement (degalactosylation) by water or an acceptor is initiated by proton abstraction by Glu461. Both of these displacements occur via planar oxocarbenium ion‐like transition states. The acceptor reaction with glucose is important for the formation of allolactose, the natural inducer of the lac operon.
Environmental Awareness and Sustainable Development in the Russian Federation
Authors: Crotty Jo , Hall Sarah Marie
Published: September 2012

Drawing on empirical research from a qualitative study in the Russian Federation, this paper contributes to the limited academic literature on environmental awareness and sustainable development in Russia. Using data from nearly 100 interviews with firms, NGOs and environmental regulators, we explore current barriers to public environmental awareness and the avenues to sustainable development, in the context of a transition country. We conclude by calling for further research that investigates the possibilities for environmental education and sustainability in contemporary Russian society and the institutional barriers thereto. Copyright © 2012 John Wiley & Sons, Ltd and ERP Environment.
‘Sustainable Development’: the ‘Unsustainable’ Development of a Concept in Political Discourse
Authors: Kambites Carol Jill
Published: September 2012

This article uses critical discourse analysis to analyse national level discourses of sustainable development in the UK through the 1990s and 2000s, as revealed in five documents produced by successive national governments during this period. After briefly reviewing the concept of sustainable development and its interpretations, national sustainable development discourses are analysed in the context of the wider political discourses that have arisen around the political ideologies of neo‐liberalism, Thatcherism and New Labour. A critical discourse analysis, using the concept of ‘discursive techniques’, reveals the way in which the concept of sustainable development has been adapted to conform to the dominant political discourses of neo‐liberalism, Thatcherism and New Labour. In this process, the term has been used to emphasize the compatibility of economic growth and environmental protection, and hence, arguably, has been used to avoid rather than to facilitate radical action. Copyright © 2012 John Wiley & Sons, Ltd and ERP Environment.
An overview of the Amber biomolecular simulation package
Authors: Salomon‐Ferrer Romelia , Case David A. , Walker Ross C.
Published: September 2012

Molecular dynamics (MD) allows the study of biological and chemical systems at the atomistic level on timescales from femtoseconds to milliseconds. It complements experiment while also offering a way to follow processes difficult to discern with experimental techniques. Numerous software packages exist for conducting MD simulations of which one of the widest used is termed Amber. Here, we outline the most recent developments, since version 9 was released in April 2006, of the Amber and AmberTools MD software packages, referred to here as simply the Amber package. The latest release represents six years of continued development, since version 9, by multiple research groups and the culmination of over 33 years of work beginning with the first version in 1979. The latest release of the Amber package, version 12 released in April 2012, includes a substantial number of important developments in both the scientific and computer science arenas. We present here a condensed vision of what Amber currently supports and where things are likely to head over the coming years. Figure 1 shows the performance in ns/day of the Amber package version 12 on a single‐core AMD FX‐8120 8‐Core 3.6GHz CPU, the Cray XT5 system, and a single GPU GTX680. © 2012 John Wiley & Sons, Ltd.

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Software > Molecular Modeling