bluuebunny/crossref_metadata_2025 huggingface dataset:
Longitudinal observation of Epstein–Barr virus antibodies in athletes during a competitive season
Authors: Pottgiesser Torben , Schumacher Yorck Olaf , Wolfarth Bernd , Schmidt‐Trucksäss Arno , Bauer Georg
Published: July 2012

Epstein–Barr virus (EBV) serology continues to be the first diagnostic test when infectious mononucleosis is suspected. Due to possible mild immunosuppression in competitive athletes, EBV reactivation determined by increases in salivary viral load have been identified as one possible cause in recurrent respiratory infections. The long‐term variation in EBV antibody levels in athletes compared to a control group remains unclear. The purpose of the study was to investigate the time course of changes in concentration of EBV antibodies in athletes with special emphasis on antibodies against early antigens (EAs) and avidity determination. During a competition season of approximately 12 months, the serological status of 15 biathletes (age 27 ± 3 years, 7 female, 8 male, international to Olympic level) was compared with 11 controls (age 23 ± 1 years; 1 female 10 male) at multiple time points. In addition, 43 healthy swimmers (age 22 ± 4 years, 18 female, 25 male, national to international level) were tested to validate the results with only two time points interspersed by approximately 6 months of intensive physical exercise. Analysis of quantitative antibody intensity bands revealed stable values during a competition season. In particular, IgG‐antibodies against EAs may persist and were found in 15% of past infections in swimmers exhibiting fluctuations in concentration after 6 months. These results provide evidence that positive Anti‐EA‐IgG may persist in healthy athletes and thus, should not be used to diagnose EBV reactivations or to identify a compromised immune function. J. Med. Virol. 84:1415–1422, 2012. © 2012 Wiley Periodicals, Inc.
Investigation of polyomaviruses replication in pediatric patients with nephropathy receiving rituximab
Authors: Delbue Serena , Ferraresso Mariano , Elia Francesca , Belingheri Mirco , Carloni Camilla , Signorini Lucia , Carluccio Silvia , Dallari Simone , Ghio Luciana , Ferrante Pasquale
Published: July 2012

Rituximab is a chimeric monoclonal antibody reacting with the CD20 antigen on B cells. It has been proposed as treatment for the idiopathic nephrotic syndrome, recurrent idiopathic nephropathy, and focal segmental glomerulosclerosis refractory to steroids. Rituximab influences T‐cell immunity and may predispose the patients to opportunistic infections, such as progressive multifocal leukoencephalopathy caused by the polyomavirus JC (JCV). The risk of latent viruses infections/reactivations in pediatric patients receiving monoclonal antibodies is not well known yet. In this longitudinal 6‐month study, the effects of rituximab on JCV and BK virus (BKV) replication have been investigated. Blood, serum, and urine samples have been collected monthly from 11 pediatric patients (mean age: 11 years) with the idiopathic nephrotic syndrome and recurrent idiopathic nephropathy, under rituximab therapy. JCV and BKV real‐time PCRs and sequencing of the viral protein 1 and the non‐coding control region have been conducted. The same investigations have been undertaken on samples collected from eight pediatric patients (controls, mean age: 6 years), with idiopathic nephrotic syndrome or focal segmental glomerulosclerosis, treated with conventional chemotherapy. JCV was detected in the urine of one patient (9%), and one control (12.5%); BKV was found in the urine of 7/11 patients (63.6%) and 2/8 controls (25%) and in blood samples from four patients. No significant difference was found in the mean viral loads and in the viral molecular characterizations between the two groups. The polyomaviruses replication was not associated with rituximab therapy in children. J. Med. Virol. 84:1464–1470, 2012. © 2012 Wiley Periodicals, Inc.
Prevalence of abnormal anal cytology in women infected with HIV
Authors: Chaves Eunice Beatriz Martin , Folgierini Heloísa , Capp Edison , von Eye Corleta Helena
Published: July 2012

Anal cancer is a rare disease. Nevertheless, it may be a reason for concern among groups in which its incidence is increasing: those who engage in anoreceptive intercourse, promiscuous persons, and those with sexually transmitted infections (HPV and HIV). The aim of this study was to evaluate the prevalence of abnormal anal cytology in women infected with HIV seen at Hospital de Clínicas de Porto Alegre, Brazil. A cross‐sectional design was used. Anal smear screening was offered to all women infected with HIV seen at the hospital's outpatient sexually transmitted infections clinic from March 2006 to March 2008. A total of 184 patients were thus enrolled. Only patients who gave written consent were included in the study. The prevalence of abnormal anal cytology was 14.1% (26 patients). Twenty‐two patients presented atypical squamous cells of undetermined significance, and four exhibited low‐grade intraepithelial neoplasia. Initially, abnormal anal cytology was significantly associated with age, number of pregnancies, smoking, abnormal cervical cytology, CD4+ < 200 cells/mm3 and hepatitis C co‐infection. After adjustment, only CD4+ < 200 cells/mm3 and smoking were found to increase the risk of altered anal cytology. The anal Pap method described is simple and can be used for screening in cohorts of HIV‐positive women who are at risk of developing anal carcinoma, mainly those with CD4+ counts <200 cells/mm3 and smokers. J. Med. Virol. 84:1335–1339, 2012. © 2012 Wiley Periodicals, Inc.
Molecular epidemiology of norovirus gastroenteritis outbreaks in New Zealand from 2002–2009
Authors: Greening Gail E. , Hewitt Joanne , Rivera‐Aban Malet , Croucher Dawn
Published: July 2012

Noroviruses are the most common cause of acute non‐bacterial gastroenteritis outbreaks worldwide, including New Zealand. New Zealand has a population of 4.4 million, which allows for centralized outbreak surveillance and a Norovirus Reference Laboratory, which facilitates efficient diagnosis, surveillance, and tracking of norovirus outbreaks. Norovirus outbreak strains are identified, sequenced, and compared with international reference strains. Between January 2002 and December 2009, 1,206 laboratory‐confirmed norovirus outbreaks were recorded. The predominant outbreak settings were healthcare institutions for the elderly and acute care patients. Other outbreak settings included catering establishments, cruise ships, homes, community events, school camps, child‐related settings, and consumption of contaminated shellfish. Of the 1,206 outbreaks, 105 (8.7%) were caused by norovirus genogroup I (GI) strains, 1,085 (89.9%) were caused by genogroup II (GII) strains, and both GI and GII strains were detected in 9 (0.8%) outbreaks. The genogroup was not identified in 7 (0.6%) outbreaks. A range of norovirus genotypes, including GI genotypes 1–6, GII genotypes 2–8, and GII.12, were associated with these outbreaks. The predominant genotype was GII.4, which was identified in 825 (68.4%) outbreaks. Norovirus GII.4 variant strains, including 2002 (Farmington Hills), 2004 (Hunter), 2006a (Laurens, Yerseke), 2006b (Minerva), and 2010 (New Orleans) implicated in overseas outbreaks also occurred in New Zealand, providing evidence of global spread. J. Med. Virol. 84:1449–1458, 2012. © 2012 Wiley Periodicals, Inc.
Isolation of saffold virus type 2 in green monkey kidney cells
Authors: Blomqvist Soile , Lappalainen Maija , Paananen Anja , Ylipaasto Petri , Roivainen Merja
Published: July 2012

Saffold viruses (SAFV) have been discovered recently and they are classified into Theilovirus species in genus Cardiovirus in the Picornaviridae family. SAFV, especially those belonging to the genotype 2, have been difficult to propagate in laboratory cell lines. This study describes the successful isolation of an efficiently growing SAFV‐2 strain directly from a stool specimen by standard virological methods. The availability of SAFV isolates that can be propagated to high titers is crucial to the future studies on pathogenesis and epidemiology of these novel human viruses. J. Med. Virol. 84:1497–1500, 2012. © 2012 Wiley Periodicals, Inc.
Detection of a new SRS‐promoting phonon mode and cross‐cascaded χ(3)‐nonlinear lasing in single crystals of calcite (trigonal CaCO3)
Authors: Bohat L. , Becker P. , Rhee H. , Lux O. , Eichler H.J. , Yoneda H. , Kaminskii A.A.
Published: July 2012

For calcite (CaCO3), one of the pioneer crystals in nonlinear optics, new results of stimulated Raman scattering (SRS) spectroscopy are presented. Among them are the discovery of a new SRS‐promoting vibration mode with ωSRS2 ≈︁ 282 cm‐1 and its participation, together with the main SRS mode ωSRS1 ≈︁ 1086.5 cm‐1, in cross‐cascaded (χ(3) ↔ χ(3)) nonlinear‐lasing generation, as well as the observation of efficient self‐upconversion via cascaded parametric four‐wave processes of one‐micron Stokes and anti‐Stokes χ(3)‐lasing into the UV‐region of third harmonic generation. The investigations show that calcite is able to generate a χ(3)‐lasing comb of more than two octaves bandwidth. The article also gives a brief review on the discovery and study of the SRS‐effect in natural crystals (minerals), which have expanded our ability to study the photon‐phonon nonlinear‐laser interactions in crystalline materials. A short summary of information about χ(3)‐lasing properties of the triangular planar structure units in SRS‐active crystals is included.
The Bohr Theorem for slice regular functions
Authors: Rocchetta Chiara Della , Gentili Graziano , Sarfatti Giulia
Published: July 2012

In this paper we prove the Bohr Theorem for slice regular functions. Following the historical path that led to the proof of the classical Bohr Theorem, we also extend the Borel‐Carathéodory Theorem to the new setting.
The role of backpressure during large scale Equal‐Channel Angular Pressing
Authors: Frint P. , Hockauf M. , Halle T. , Wagner M.F.‐X. , Lampke T.
Published: July 2012

In this study we investigate the influence of various magnitudes of backpressure (0 to 200 MPa) during large scale (cross‐section 50×50 mm2) equal‐channel angular pressing (ECAP). We focus on the homogeneity of the induced strain and, within this context, on the homogeneity of the resulting mechanical properties after one pass of ECAP at room temperature. We find that large scale ECAP without the application of a backpressure clearly leads to heterogeneous shear strains, causing heterogeneous mechanical properties. A pronounced maximum of hardness next to a local minimum at the billet's bottom occurs; in the absence of backpressure during processing, its expansion covers almost one half of the cross‐section. The application of a backpressure close to the material's proof stress after processing (in this case 200 MPa) results in an excellent homogeneity with a negligible local heterogeneity at the bottom of the billet.
Prevalence of diarrheagenic Escherichia coli virulence genes in the feces of slaughtered cattle, chickens, and pigs in Burkina Faso
Authors: Kagambèga Assèta , Martikainen Outi , Siitonen Anja , Traoré Alfred S. , Barro Nicolas , Haukka Kaisa
Published: July 2012

We investigated the prevalence of the virulence genes specific for five major pathogroups of diarrheagenic Escherichia coli (DEC) in primary cultures from feces of animals slaughtered for human consumption in Burkina Faso. For the study, 704 feces samples were collected from cattle (n = 304), chickens (n = 350), and pigs (n = 50) during carcass processing. The presence of the virulence‐associated genes in the mixed bacterial cultures was assessed using 16‐plex polymerase chain reaction (PCR). Virulence genes indicating presence of DEC were detected in 48% of the cattle, 48% of the chicken, and 68% of the pig feces samples. Virulence genes specific for different DECs were detected in the following percentages of the cattle, chicken, and pig feces samples: Shiga toxin‐producing E. coli (STEC) in 37%, 6%, and 30%; enteropathogenic E. coli (EPEC) in 8%, 37%, and 32%; enterotoxigenic E. coli (ETEC) in 4%, 5%, and 18%; and enteroaggregative E. coli (EAEC) in 7%, 6%, and 32%. Enteroinvasive E. coli (EIEC) virulence genes were detected in 1% of chicken feces samples only. The study was the first of its kind in Burkina Faso and revealed the common occurrence of the diarrheal virulence genes in feces of food animals. This indicates that food animals are reservoirs of DEC that may contaminate meat because of the defective slaughter and storage conditions and pose a health risk to the consumers in Burkina Faso.
Surgical strategies based on standard templates for microsurgical reconstruction of oral cavity and oropharynx soft tissue: A 20 years' experience
Authors: Caliceti Umberto , Piccin Ottavio , Sgarzani Rossella , Negosanti Luca , Fernandez Ignacio Javier , Nebiaj Aurel , Contedini Federico , Cipriani Riccardo , Ceroni Alberto Rinaldi
Published: July 2012

Background

Microsurgical reconstruction has become the worldwide gold standard for repairing surgical defects in head and neck cancer. The aim of this article is to describe a standardized reconstructive approach to the oral cavity and oropharynx soft tissue defects.

Patients and methods

Since 1992, the authors have treated 163 patients affected by oral cavity and oropharynx cancer, performing a total of 175 flaps. A systematic postoperative functional study prompted a surgical strategy, in terms of flap choice, shape, and insetting. A two‐dimensional template was used to obtain a three‐dimensional reconstruction for the best functional and aesthetic outcome. To simplify preoperative planning, surgical resections were divided into a set number of classes. The templates, flap choice, and insetting are described for each region.

Results

Complications consisted of seven partial necroses of the flap which easily resolved with a local toilette and 12 complete necroses of the flap due to vascular thrombosis, these patients required a secondary reconstruction with another free flap.

Functional results were systematically evaluated in the first 60 patients of our series with particular attention to the swallowing function, which was analyzed by both videofluoroscopy and functional endoscopic evaluation of swallowing. Results showed a good functional recovery with the described reconstructive techniques.

Conclusion

A standardized surgical strategy based on reproducible templates might facilitate less experienced surgeons in analyzing the problem, choosing the best technical solution and foreseeing the functional outcomes. © 2012 Wiley Periodicals, Inc. Microsurgery, 2013.
Composite osseomusculocutaneous sternum, ribs, thymus, pectoralis muscles, and skin allotransplantation model of bone marrow transplantation
Authors: Bozkurt Mehmet , Klimczak Aleksandra , Nasir Serdar , Zor Fatih , Krokowi̇cz Lukasz , Siemionow Maria
Published: July 2012

Cellular and vascularized bone marrow cells have been used to induce donor‐specific chimerism in various models of composite tissue allotransplantation. Although thymus transplantation has been reported in the literature, the effect of thymus transplantation on chimerism levels in vascularized bone containing composite tissue allotransplantation has not been reported. In this study, a new method for composite vascularized sternal bone marrow transplant model is descried that can be applied to augment chimerism after transplantation. A total of seven composite osseomusculocutaneous sternum, ribs, thymus, pectoralis muscles, and skin transplantations were performed in two groups. The first group (n = 5) was designed as an allotransplantation group and the second group (n = 2) was designed as an isotransplantation group. Composite osseomusculocutaneous sternum, ribs, thymus, and pectoralis muscles allografts were harvested on thecommon carotid artery and external jugular vein and a heterotopic transplantation was performed to the inguinal region of the recipient rat. Cyclosporine A monotherapy was administered in order to prevent acute and chronic allograft rejection. Animals sacrificed when any sign of rejection occurred. The longest survival was 156 day post‐transplant. Assessment of bone marrow cells within sternum bone component and flow cytometry analysis of donor‐specific chimerism in the peripheral blood of recipients were evaluated. Our results showed that thiscomposite allograft carried 7.5 × 106 of viable hematopoietic cells within the sternum component. At day 7 post‐transplant chimerism was developed in T‐cell population and mean level was assessed at 2.65% for RT1n/CD4 and at 1.0% for RT1n/CD8. In this study, a newosseomusculocutaneous sternum, ribs, thymus, pectoralis muscle, and skin allotransplantation model is reported which can be usedto augment hematopoietic activity for chimerism induction after transplantation. © 2012 Wiley Periodicals, Inc. Microsurgery, 2013.
The general analytical and numerical solution for the modified KdV equation with convergence analysis
Authors: Rostamy D. , Zabihi F.
Published: July 2012

We investigate the analytical and numerical solutions of the modified Kortweg de Vries equation by applying the idea of commutative hypercomplex mathematics, He's homotopy perturbation method as a simple particular procedure, and the Runge–Kutta discontinuous Galerkin methods. Moreover, we discuss at great length the convergence conditions for this equation by using the Banach fixed point theory, which could provide a good iteration algorithm. Finally, we compare the homotopy perturbation method with some standard ideas same as the Runge–Kutta discontinuous Galerkin method by some numerical illustrations. Copyright © 2012 John Wiley & Sons, Ltd.
Patient‐identified disease burden in facioscapulohumeral muscular dystrophy
Authors: Johnson Nicholas E. , Quinn Christine , Eastwood Eileen , Tawil Rabi , Heatwole Chad R.
Published: July 2012

Introduction:The multitude of symptoms associated with facioscapulohumeral muscular dystrophy (FSHD) disease burden are of varying importance. The extent of these symptoms and their cumulative effect on the FSHD population is unknown.Methods:We conducted interviews with adult FSHD patients to identify which symptoms have the greatest effect on their lives. Each interview was recorded, transcribed, coded, and analyzed using a qualitative framework technique, triangulation, and a three‐investigator consensus approach.Results:One thousand three hundred seventy‐five quotes were obtained through 20 patient interviews. Two hundred fifty‐one symptoms of importance were identified representing 14 themes of FSHD disease burden. Symptoms associated with mobility impairment, activity limitation, and social role limitation were most frequently mentioned by participants.Conclusions:There are multiple themes and symptoms, some previously underrecognized, that play a key role in FSHD disease burden. Muscle Nerve, 2012
Do Child Development Accounts Promote Account Holding, Saving, and Asset Accumulation for Children's Future? Evidence from a Statewide Randomized Experiment
Authors: Nam Yunju , Kim Youngmi , Clancy Margaret , Zager Robert , Sherraden Michael
Published: July 2012

This study examines the impacts of Child Development Accounts (CDAs) on account holding, saving, and asset accumulation for children, using data from the SEED for Oklahoma Kids experiment (SEED OK). SEED OK, a policy test of universal and progressive CDAs, provides a 529 college savings plan account to every infant in the treatment group with automatic account opening and an initial deposit. SEED OK also encourages treatment participants to open their own 529 accounts with an account opening incentive and a savings match. Using a sample of infants randomly selected from birth records (N = 2,670) and randomly assigned to treatment and control groups, this study runs probit and ordinary least squares (OLS) regressions. Analyses show significant differences between treatment and control groups in all outcome measures in the targeted accounts. Nearly 100 percent of the treatment group accepted the automatically opened state‐owned account. Compared to 1 percent of the control group, 16 percent of the treatment group hold a participant‐owned account. On average, the treatment group has saved significantly larger amounts in participant‐owned accounts, although a difference in savings amount is modest between the two groups ($47 vs. $13). A difference in total 529 assets of $1,040 is estimated between the treatment and control groups. These early findings from SEED OK suggest that CDAs have positive effects on savings and asset accumulation for children's future development. Further research is required to test long‐term cost effectiveness of CDAs.
Pharmacotherapy for personality disorder—Prescribing practice at a high secure hospital: A preliminary report
Authors: D'Silva Karen , Chadwick Karen , Egleston Paul , Milton John , Ferriter Mike , Abdelrazek Tarek
Published: July 2012

The aim of this study was to examine the prescription of psychotropic medication for patients with a primary diagnosis of personality disorder (PD) detained at Rampton High Secure Hospital, compared with that for patients with a primary diagnosis of mental illness. The name and the dose of psychotropic medication prescribed for each patient in the sample, on 2 July 2010, were examined. Although nearly all patients with a primary diagnosis of mental illness were prescribed psychotropic medication (98%), the percentage within the Personality Disorder (73%) and the Dangerous and Severe Personality Disorder services (62%) was also high, with the most commonly prescribed drug being an antipsychotic in all groups. The dose of antipsychotic and mood‐stabilizing medication was lower for patients with a primary diagnosis of PD, and clozapine was the antipsychotic of choice for a significant proportion of these patients. Medication may have a key role to play in the management of some groups of patients with PD. Copyright © 2012 John Wiley & Sons, Ltd.
Prevalence of scoliosis in cystic fibrosis
Authors: Fainardi Valentina , Koo Sergio D. , Padley Simon P.G. , Lam Sonia H.Y. , Bush A.
Published: July 2012

Background

The prevalence of idiopathic scoliosis in the general pediatric population is reported to be between 0.5% and 3.2%. Previous studies have reported an increased prevalence of scoliosis in children with cystic fibrosis (CF).

Hypothesis

The prevalence of scoliosis in CF children is greater than in the normal population.

Methods

Chest X‐rays of 319 patients attending the Royal Brompton CF Centre were reviewed. The Cobb angle of any spinal lateral curvature was measured. Scoliosis was defined as a Cobb angle of more than 10°.

Results

Median age of the whole group of patients was 10.9 years (range 1.1–18 years), 53% were females. Seven patients (2.2%) had radiological signs of scoliosis, their mean age was 14.5 ± 2.3 years (range: 11.5–18 years), 5 were females. Age at onset of scoliosis was between 5 and 10 years for three patients and over 10 years for the others. All the curves were thoracic and with right convexity: apices between T7 and T9 for the single curves (n = 5) and between T4 and T5 (n = 2) for the double curves.

Conclusion

CF patients showed a similar prevalence of scoliosis as in the normal population (2.2% vs. 0.5–3.2%). There was the same gender (female) and side (right‐sided) predilection as in normal population. Pediatr Pulmonol. 2013; 48:553–555. © 2012 Wiley Periodicals, Inc.
Application of split‐green fluorescent protein for topology mapping membrane proteins in Escherichia coli
Authors: Toddo Stephen , Söderström Bill , Palombo Isolde , von Heijne Gunnar , Nørholm Morten H. H. , Daley Daniel O.
Published: July 2012

A topology map of a membrane protein defines the location of transmembrane helices and the orientation of soluble domains relative to the membrane. In the absence of a high‐resolution structure, a topology map is an essential guide for studying structure–function relationships. Although these maps can be predicted directly from amino acid sequence, the predictions are more accurate if combined with experimental data, which are usually obtained by fusing a reporter protein to the C‐terminus of the protein. However, as reporter proteins are large, they cannot be used to report on the cytoplasmic/periplasmic location of the N‐terminus of a protein. Here, we show that the bimolecular split‐green fluorescent protein complementation system can overcome this limitation and can be used to determine the location of both the N‐ and C‐termini of inner membrane proteins in Escherichia coli.
2 MeV e‐irradiation UHVEM study on the impact of O and Ge doping on {113}‐defect formation in Si
Authors: Vanhellemont J. , Yasuda H. , Tokumoto Y. , Ohno Y. , Suezawa M. , Yonenaga I.
Published: July 2012

First results are presented of a study on the impact of O and Ge doping on {113}‐defect formation in Si using in situ 2 MeV e‐irradiation in a high voltage electron microscope. Comparison with undoped Si, reveals a suppression of {113}‐defect formation due to O and Ge. The observations are discussed in the frame of a theoretical model assuming quasi‐chemical reactions to describe the intrinsic point defect behaviour during irradiation as a function of irradiation temperature and specimen thickness. It is shown that for irradiations at high temperatures, intrinsic point defect diffusivity values derived from crystal growth and metal diffusion experiments can be used to explain the observations semi‐quantitatively.
Facile fabrication of forest‐like ZnO hierarchical structures on conductive fabric substrate
Authors: Ko Yeong Hwan , Kim Sunkook , Park Wook , Yu Jae Su
Published: July 2012

Forest‐like ZnO hierarchical structures were synthesized on the conductive fabric substrate via a simple one‐step electrochemical deposition process. By applying externally a high cathodic voltage to the samples, ZnO microrods were aligned on the seed coated layer and then ZnO branches were formed on the pillars of ZnO microrods, which was caused by the strong deposition potential between the pillars of ZnO microrods and the Zn2+ dissolved in growth solution. At the external cathodic voltage of –3 V, the optimized forest‐like ZnO hierarchical structures exhibited high density, high porosity, and good crystallinity. These fabricated forest‐like ZnO hierarchical structures are potentially useful for electronic and chemical sensing applications. (© 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
A route to transparent bulk metals
Authors: Schwingenschlögl U. , Schuster C. , Frésard R.
Published: July 2012

Hypothetical compounds based on a sapphire host are investigated with respect to their structural as well as electronic features. The results are obtained by electronic structure calculations within density functional theory and the generalized gradient approximation. A quarter of the Al atoms in Al2O3 is replaced by a 4d transition metal M ion, with d0 to d9 electronic configuration. We perform structure optimizations for all the compounds and analyze the electronic states. Due to the sizeable band gap of the Al2O3 host, we can identify promising candidates for transparent bulk metals. We explain the mechanisms leading to this combination of materials properties. (© 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Absorption‐mode spectra on the dynamically harmonized Fourier transform ion cyclotron resonance cell
Authors: Qi Yulin , Witt Matthias , Jertz Roland , Baykut Gökhan , Barrow Mark P. , Nikolaev Eugene N. , O'Connor Peter B.
Published: July 2012

RATIONALE

The recently designed dynamically harmonized Fourier transform ion cyclotron resonance (FT‐ICR) cell creates a more harmonized electric field for the detection of the cyclotron motion of ions and prolongs the ion transient from seconds to minutes. In order to achieve its best performance, phase correction was applied in the spectra, and new advantages of the absorption‐mode were revealed.

METHODS

Spectra were acquired from both simple standard and complex mixtures using either narrowband or broadband mode, and the data were processed to compare the performance of the spectra in magnitude and absorption‐mode.

RESULTS

The research shows that phase correction works well with data from Nikolaev's new cell, which produces the maximum improvement in resolving power (2×), and improves the match with the theoretical intensities of the isotopic peaks. In addition, the harmonic peaks can be diagnosed immediately in the absorption‐mode.

CONCLUSIONS

The manuscript demonstrates absorption‐mode spectra from Nikolaev's ICR cell, which will be of interest to the community. The improved relative peak intensities and immediate identification of harmonic peaks will facilitate data interpretation. Copyright © 2012 John Wiley & Sons, Ltd.
High‐expression EGFR/cell membrane chromatography‐online‐high‐performance liquid chromatography/mass spectrometry: rapid screening of EGFR antagonists from Semen Strychni
Authors: Sun Meng , Guo Ying , Dai Bingling , Wang Chen , He Langchong
Published: July 2012

RATIONALE

Traditional methods for screening active compounds from complex system such as traditional Chinese medicines are relatively cumbersome and time‐consuming. In order to improve this situation, we established an online analytical method for screening, separation and identification EGFR antagonists from traditional Chinese medicines, which is described in this study.

METHODS

Cells with high EGFR expression levels were used to prepare the cell membrane stationary phase for the EGFR cell membrane chromatography model with the purpose of screening active compounds. Separation of the retention fractions was achieved by the high‐performance liquid chromatography, and identification was conducted via electrospray ionization quadrupole mass spectrometry. The inhibitory effects of active compounds on EGFR cell growth were also demonstrated in vitro.

RESULTS

The screening results showed that vauquline and strychnine from Semen Strychni could be active components acting on EGFR similarly to gefitinib as a control drug. Results from biological trials showed that vauquline and strychnine inhibited cell proliferation of HEK293/EGFR cells, and inhibited Erk phosphorylation, and can effectively reduce expression of downstream signaling molecules.

CONCLUSIONS

This EGFR cell membrane chromatography‐online‐high‐performance liquid chromatography/tandem mass spectrometry method can be applied for rapid screening, separation and identification of EGFR antagonists from traditional Chinese medicines and should be useful for drug discovery with natural medicinal herbs. Copyright © 2012 John Wiley & Sons, Ltd.
Classification and characterization of unknown cytokinins into essential types by in‐source collision‐induced dissociation electrospray ionization ion trap mass spectrometry
Authors: Liu Shichang , Chen Weiqi , Fang Kai , Jiang Xiangning , Gai Ying
Published: July 2012

RATIONALE

Mass spectrometry is effective for determination of cytokinins, which are bioactive compounds with an adenine‐core structure. However, it is difficult to characterize any cytokinin compound without the relevant standard or known molecular structure information. With a limited number of standards, an in‐source collision‐induced dissociation (CID) method for characterization and classification of unknown cytokinins was described in this study.

METHODS

Cytokinins were separated by high‐performance liquid chromatography and then analyzed by electrospray ionization ion trap mass spectrometry using an in‐source CID technique and multiple reaction monitoring (MRM) mode.

RESULTS

Based on the properties of multi‐stage fragmentation in mass spectrometry, naturally occurring cytokinins were classified into four types (zeatin, dihydrogen zeatin, isopentenyl adenine and benzyl adenine) by losing their conjugated sugar, sugar phosphate and other substituents in the source region. Following this technique, seven unknown cytokinins were characterized from roots of maize (Zea mays) without standards and one of them was finally confirmed to be cis‐zeatin‐riboside.

CONCLUSIONS

An in‐source CID technique combined with MRM mass spectrometry was developed to provide product ion information for identification of cytokinins and to afford guidance for the discovery of unknown cytokinins. Copyright © 2012 John Wiley & Sons, Ltd.
‘Click’ Preparation of CuPt Nanorod‐Anchored Graphene Oxide as a Catalyst in Water
Authors: Yang Hyunseung , Kwon Yongwoo , Kwon Taegyun , Lee Hyunjoo , Kim Bumjoon J.
Published: July 2012

In this paper, a simple and powerful method of producing nanoparticle‐anchored graphene oxide (GO) composites using a ‘click’ reaction is demonstrated. This method affords a facile means of anchoring of nanoparticles with various shapes and sizes on the GO. CuPt nanorods with controlled size, aspect ratio (from 1 to 11), and uniformity are synthesized. Transmission electron microscopy, Fourier transform infrared spectroscopy, and X‐ray photoelectron spectroscopy measurements are made to monitor the formation and characterize the properties of the CuPt nanorod‐grafted GO composites. Their catalytic properties in the water phase are investigated using an o‐phenylenediamine oxidation reaction. The results of this study clearly demonstrate that nonpolar CuPt nanorods immobilized on GO can function as a catalyst in an aqueous solution and that GO can be used as a catalytic nanorod support.
Career development during childhood and adolescence
Authors: Porfeli Erik J. , Lee Bora
Published: July 2012

Identity development is central to the career development of children and adolescents. This article reviews the literature pertaining to identity development as being composed of career exploration, commitment, and reconsideration and offers some implications for career interventions.
Support for career development in youth: Program models and evaluations
Authors: Mekinda Megan A.
Published: July 2012

This article examines four influential programs—Citizen Schools, After School Matters, career academies, and Job Corps—to demonstrate the diversity of approaches to career programming for youth. It compares the specific program models and draws from the evaluation literature to discuss strengths and weaknesses of each. The article highlights three key lessons derived from the models that have implications for career development initiatives more generally: (1) career programming can and should be designed for youth across a broad age range, (2) career programming does not have to come at the expense of academic training or preparation for college, and (3) program effectiveness depends on intentional design and high‐quality implementation.
Interpreting LHC Higgs results from natural new physics perspective
Authors: Carmi Dean , Falkowski Adam , Kuflik Eric , Volansky Tomer
Published: July 2012

Abstract

We analyze the 2011 LHC and Tevatron Higgs data in the context of simplified new physics models addressing the naturalness problem. These models are expected to contain new particles with sizable couplings to the Higgs boson, which can easily modify the Higgs production cross sections and branching fractions. We focus on searches in the h → ZZ
∗ → 4 l, h → WW
∗ → lνlν, h → γγ, hjj → γγjj and
$ hV \to b\overline b V $
channels. Combining the available ATLAS, CMS, and Tevatron data in these channels, we derive constraints on an effective low-energy theory of the Higgs boson. We then map several simplified scenarios to the effective theory, capturing numerous natural new physics models such as supersymmetry and Little Higgs, and extract the constraints on the corresponding parameter space. We show that simple models where one fermionic or one scalar partner is responsible for stabilizing the Higgs potential are already constrained in a non-trivial way by LHC and Tevatron Higgs data.
On the inflaton potential from antibranes in warped throats
Authors: Bena Iosif , Giecold Gregory , Graña Mariana , Halmagyi Nick
Published: July 2012

Abstract

We compute the force between a stack of smeared antibranes at the bottom of a warped throat and a stack of smeared branes at some distance up the throat, both for anti-D3 branes and for anti-M2 branes. We perform this calculation in two ways: first, by treating the antibranes as probes in the background sourced by the branes and second, by treating the branes as probes in the candidate background sourced by the antibranes. These two very different calculations yield exactly the same expression for the force, for all values of the brane-antibrane separation. This indicates that the force between a brane and an antibrane is not screened in backgrounds where there is positive charge dissolved in flux, and gives a way to precisely compute the inflaton potential in certain string cosmology scenarios.
Cell surface display of a β-glucosidase employing the type V secretion system on ethanologenic Escherichia coli for the fermentation of cellobiose to ethanol
Authors: Muñoz-Gutiérrez Iván , Oropeza Ricardo , Gosset Guillermo , Martinez Alfredo
Published: July 2012

We used the autodisplay system AIDA-I, which belongs to the type V secretion system (TVSS), to display the β-glucosidase BglC from Thermobifida fusca on the outer membrane of the ethanologenic Escherichia coli strain MS04 (MG1655 ∆pflB, ∆adhE, ∆frdA, ∆xylFGH, ∆ldhA, PpflB::pdc  Zm-adhB  Zm). MS04 that was transformed with the plasmid pAIDABglCRHis showed cellobiase activity (171 U/gCDW) and fermented 40 g/l cellobiose in mineral medium in 60 h with an ethanol yield of 81 % of the theoretical maximum. Whole-cell protease treatment, SDS-PAGE, and Western-blot analysis demonstrated that BglC was attached to the external surface of the outer membrane of MS04. When attached to the cells, BglC showed 93.3 % relative activity in the presence of 40 g/l ethanol and retained 100 % of its activity following 2 days of incubation at 37 °C with the same ethanol concentration. This study shows the potential of the TVSS (AIDA-I) and BglC as tools for the production of lignocellulosic bio-commodities.
Biofilm establishment and heavy metal removal capacity of an indigenous mining algal-microbial consortium in a photo-rotating biological contactor
Authors: Orandi S , Lewis D M , Moheimani N R
Published: July 2012

An indigenous mining algal-microbial consortium was immobilised within a laboratory-scale photo-rotating biological contactor (PRBC) that was used to investigate the potential for heavy metal removal from acid mine drainage (AMD). The microbial consortium, dominated by Ulothrix sp., was collected from the AMD at the Sar Cheshmeh copper mine in Iran. This paper discusses the parameters required to establish an algal-microbial biofilm used for heavy metal removal, including nutrient requirements and rotational speed. The PRBC was tested using synthesised AMD with the multi-ion and acidic composition of wastewater (containing 18 elements, and with a pH of 3.5 ± 0.5), from which the microbial consortium was collected. The biofilm was successfully developed on the PRBC’s disc consortium over 60 days of batch-mode operation. The PRBC was then run continuously with a 24 h hydraulic residence time (HRT) over a ten-week period. Water analysis, performed on a weekly basis, demonstrated the ability of the algal-microbial biofilm to remove 20–50 % of the various metals in the order Cu > Ni > Mn > Zn > Sb > Se > Co > Al. These results clearly indicate the significant potential for indigenous AMD microorganisms to be exploited within a PRBC for AMD treatment.
Enhanced leavening properties of baker’s yeast overexpressingMAL62with deletion ofMIG1in lean dough
Authors: Sun Xi , Zhang Cuiying , Dong Jian , Wu Mingyue , Zhang Yan , Xiao Dongguang
Published: July 2012

This study aimed to increase maltose fermentation in industrial baker’s yeast to increase its leavening properties. To this end, we overexpressed MAL62 encoding alpha-glucosidase (maltase) and deleted MIG1 encoding a transcriptional repressor that regulates MAL gene expression. Strain overexpressing MAL62 showed 46.3 % higher alpha-glucosidase activity and enhanced leaving activity than the parental strain when tested in glucose–maltose low sugar model liquid dough (LSMLD). Deleting MIG1 was much less effective, but it could further strengthen leavening properties in a strain overexpressing MAL62. The relationship between maltose permease and alpha-glucosidase was further dissected by transforming the two genes. The results indicated that without increasing the maltose permease activity, maltose metabolism could also be enhanced by the increased alpha-glucosidase activity. Previous strategies for strain improvement have targeted the enhancement of alpha-glucosidase and maltose permease activities in concert. Our results suggest that increasing alpha-glucosidase activity is sufficient to improve maltose fermentation in lean dough.
Production of erythritol and mannitol by Yarrowia lipolytica yeast in media containing glycerol
Authors: Tomaszewska Ludwika , Rywińska Anita , Gładkowski Witold
Published: July 2012

Glycerol is a by-product generated in large amounts during the production of biofuels. This study presents an alternative means of crude glycerol valorization through the production of erythritol and mannitol. In a shake-flasks experiment in a buffered medium, nine Yarrowia lipolytica strains were examined for polyols production. Three strains (A UV’1, A-15 and Wratislavia K1) were selected as promising producers of erythritol or/and mannitol and used in bioreactor batch cultures and fed-batch mode. Pure and biodiesel-derived crude glycerol media both supplemented (to 2.5 and 3.25 %) and not-supplemented with NaCl were applied. The best results for erythritol biosynthesis were achieved in medium with crude glycerol supplemented with 2.5 % NaCl. Wratislavia K1 strain produced up to 80.0 g l−1 erythritol with 0.49 g g−1 yield and productivity of 1.0 g l−1 h−1. Erythritol biosynthesis by A UV’1 and A-15 strains was accompanied by the simultaneous production of mannitol (up to 27.6 g l−1). Extracellular as well as intracellular erythritol and mannitol ratios depended on the glycerol used and the presence of NaCl in the medium. The results from this study indicate that NaCl addition to the medium improves erythritol biosynthesis, and simultaneously inhibits mannitol formation.
Horizontal gene transfer and gene conversion drive evolution of modular polyketide synthases
Authors: Zucko Jurica , Long Paul F , Hranueli Daslav , Cullum John
Published: July 2012

Soil bacteria live in a very competitive environment and produce many secondary metabolites; there appears to be strong selective pressure for evolution of new compounds. Secondary metabolites are the most important source of chemical structures for the pharmaceutical industry and an understanding of the evolutionary process should help in finding novel chemical entities. Modular polyketide synthases are a particularly interesting case for evolutionary studies, because much of the chemical structure can be predicted from DNA sequence. Previous evolutionary studies have concentrated on individual modules or domains and were not able to study the evolution of orthologues. This study overcame this problem by considering complete clusters as “organisms”, so that orthologous modules and domains could be identified and used to characterise evolutionary pathways. Seventeen modular polyketide synthase clusters were identified that fell into six classes. Gene conversion within clusters was very common (affecting about 15 % of domains) and was detected by discordance in phylogenetic trees. An evolutionary model is proposed in which a single cross over between two different clusters (i.e. horizontal gene transfer) would generate a cluster of very different architecture with radically different chemical products; subsequent gene conversion and deletions would explore chemical variants. Two probable examples of such recombination were found. This model suggests strategies for detecting horizontal gene transfer in cluster evolution.
Fungal β-glucosidase expression in Saccharomyces cerevisiae
Authors: Njokweni A P , Rose S H , van Zyl W H
Published: July 2012

Recombinant Saccharomyces cerevisiae strains expressing β-glucosidases from Thermoascus aurantiacus (Tabgl1) and Phanerochaete chrysosporium (PcbglB and Pccbgl1) were constructed and compared to S. cerevisiae Y294[SFI], previously identified as the best β-glucosidase-producing strain. The PcbglB was also intracellularly expressed in combination with the lac12 lactose permease of Kluyveromyces lactis in S. cerevisiae Y294[PcbglB + Lac12]. The recombinant extracellular β-glucosidases indicated maximum activity in the pH range 4–5 and temperature optima varying from 50 to 75 °C. The S. cerevisiae Y294[Pccbgl1] strain performed best under aerobic and anaerobic conditions, producing 2.6 times more β-glucosidase activity than S. cerevisiae Y294[SFI] and an ethanol concentration of 4.8 g l−1 after 24 h of cultivation on cellobiose as sole carbohydrate source. S. cerevisiae Y294[Tabgl1] was unable to grow on cellobiose (liquid medium), whereas S. cerevisiae Y294[PcbglB + Lac12] exhibited limited growth.
An improved method of xylose utilization by recombinant Saccharomyces cerevisiae
Authors: Ma Tien-Yang , Lin Ting-Hsiang , Hsu Teng-Chieh , Huang Chiung-Fang , Guo Gia-Luen , Hwang Wen-Song
Published: July 2012

The aim of this study was to develop a method to optimize expression levels of xylose-metabolizing enzymes to improve xylose utilization capacity of Saccharomyces cerevisiae. A xylose-utilizing recombinant S. cerevisiae strain YY2KL, able to express nicotinamide adenine dinucleotide phosphate, reduced (NADPH)-dependent xylose reductase (XR), nicotinamide adenine dinucleotide (NAD+)-dependent xylitol dehydrogenase (XDH), and xylulokinase (XK), showed a low ethanol yield and sugar consumption rate. To optimize xylose utilization by YY2KL, a recombinant expression plasmid containing the XR gene was transformed and integrated into the aur1 site of YY2KL. Two recombinant expression plasmids containing an nicotinamide adenine dinucleotide phosphate (NADP+)-dependent XDH mutant and XK genes were dually transformed and integrated into the 5S ribosomal DNA (rDNA) sites of YY2KL. This procedure allowed systematic construction of an S. cerevisiae library with different ratios of genes for xylose-metabolizing enzymes, and well-grown colonies with different xylose fermentation capacities could be further selected in yeast protein extract (YPX) medium (1 % yeast extract, 2 % peptone, and 2 % xylose). We successfully isolated a recombinant strain with a superior xylose fermentation capacity and designated it as strain YY5A. The xylose consumption rate for strain YY5A was estimated to be 2.32 g/gDCW/h (g xylose/g dry cell weight/h), which was 2.34 times higher than that for the parent strain YY2KL (0.99 g/gDCW/h). The ethanol yield was also enhanced 1.83 times by this novel method. Optimal ratio and expression levels of xylose-metabolizing enzymes are important for efficient conversion of xylose to ethanol. This study provides a novel method that allows rapid and effective selection of ratio-optimized xylose-utilizing yeast strains. This method may be applicable to other multienzyme systems in yeast.