bluuebunny/crossref_metadata_2025 huggingface dataset:
Increased risk of bladder cancer following diagnosis with bladder pain syndrome/interstitial cystitis
Authors: Keller Joseph , Chiou Hung‐Yi , Lin Herng‐Ching
Published: July 2012

Aims

Interstitial cystitis/bladder pain syndrome (IC/BPS) is a prevalent disorder that may contribute to bladder cancer (BC). This cohort study set out to investigate the association between IC/BPS and BC by using a population‐based dataset.

Methods

The data for this study were sourced from the Taiwan National Health Insurance program. The case cohort comprised 7,562 patients with IC/BPS, and 22,686 randomly selected subjects were used as a comparison cohort. A Cox proportional hazards regression model (stratified by age group, geographic location, urbanization level, and the index year) was constructed to estimate the risk of subsequent BC following a diagnosis of IC/BPS. We also ran the analysis utilizing an alternative comparison cohort composed of patients with urinary incontinence (UI).

Results

In the study sample of 30,248 patients, 96 patients (0.32%) received a diagnosis of BC during the 3‐year follow‐up period; 48 (0.63% of patients with IC/BPS) were from the study cohort; and 48 (0.21% of patients without IC/BPS) were from the comparison cohort. The incidence rate of BC was 2.12 (95% CI: 1.58–2.78) per 1,000 person‐years in patients with IC/BPS and 0.70 (95% CI: 0.52–0.92) per 1,000 person‐years in comparison patients. Cox proportional analysis revealed that the adjusted HR for BC during the 3‐year follow‐up period for patients with IC/BPS was 2.95 (95% CI: 1.97–4.41) that of comparison subjects. When performing the analysis with the alternative UI comparison cohort, the adjusted HR for BC was 1.96 (95% CI: 1.14–3.39).

Conclusions

This investigation detected a novel association between BC and prior IC/BPS. Neurourol. Urodynam. 32: 58–62, 2013. © 2012 Wiley Periodicals, Inc.
Formamide‐based RNA Isolation at Above ZeroTemperatures from High Starch Cassava Tubers
Authors: Bowrin Valerie , Rouse‐Miller Judy , Sutton Fedora , Sirju‐Charran Grace
Published: July 2012

Introduction

Cassava (Manihot esculenta) tubers are a main source of carbohydrate for a large percentage of people in the tropics. However, obtaining RNA from such high starch tubers proves problematic because gelation occurs during standard isolation procedures. In preliminary studies, formamide was used to homogenise tubers at room temperature and no gelation was observed.

Objectives

To develop a simple, reproducible formamide‐based procedure for RNA isolation from high starch tissues without the initial use of liquid nitrogen or lyophilisation. A second objective was to determine the impact of storage of formamide homogenates at 4°C on RNA integrity.

Methodology

Tubers were homogenised in 100% formamide at room temperature and stored for 1, 4 or 7 days at 4°C. Homogenates were centrifuged at 14000 × g for 10 min and RNA recovered from the supernatants by isopropanol precipitation followed by dissolution in guanidinium buffer. Protein was removed by standard phenol–chloroform–isoamyl alcohol extraction and RNA recovered by isopropanol precipitation. For immediate RNA isolation, formamide homogenates can be processed without incubation at 4°C.

Results

In formamide homogenates a non‐gelatinous white pellet was observed which was identified as starch by Lugol's staining. Intact RNA was observed by agarose gel electrophoresis. The RNA was successfully used in downstream RT‐PCR reactions.

Conclusion

Formamide maintained the integrity of the RNA during tissue processing at 25 ± 2°C and storage at 4°C. This room temperature formamide‐based RNA isolation procedure met the criteria of simplicity, low‐cost, reproducibility and addressed gelation problems associated with high starch tissues. Copyright © 2012 John Wiley & Sons, Ltd.
Doppler changes in the vertebral, middle cerebral, and umbilical arteries in fetuses delivered after 34 weeks: relationship to severity of growth restriction
Authors: Morales Roselló José , Hervás Marín David , Fillol Crespo Manuel , Perales Marín Alfredo
Published: July 2012

Objective

To determine the association between Doppler changes in the fetal vertebral (VA), middle cerebral (MCA), and umbilical arteries (UA) and severity of growth restriction (FGR) in fetuses delivered after 34 weeks.

Method

Five hundred seventy‐one Doppler examinations of the VA, MCA, and UA were performed between 26 and 41 weeks of gestation. Values were converted into multiples of the median and divided into birth weight (BW) categories: BW>P10th, BW<P10th, BW<P5th, and BW<P3rd. Differences were evaluated and multivariate logistic regression models plus receiver‐operating characteristic curves were calculated to determine the accuracy of Doppler measurements for the prediction of FGR percentiles.

Results

The UA pulsatility index (PI) was significant predicting BW<P10th and BW<P3rd, the VA PI was significant predicting BW<P5th and BW<P3rd. Finally, the MCA PI was not predictive of any degree of severity of FGR. In addition, only VA and UA differences were statistically significant.

Conclusion

In fetuses delivered after 34 weeks, mild degrees of growth restriction are better associated with high UA PI whereas severe degrees are associated with low VA PI but not with low MCA PI. © 2012 John Wiley & Sons, Ltd.
Signals of progressive multifocal leukoencephalopathy for immunosuppressants: a disproportionality analysis of spontaneous reports within the US Adverse Event Reporting System (AERS)
Authors: Schmedt Niklas , Andersohn Frank , Garbe Edeltraut
Published: July 2012

Purpose

Progressive multifocal leukoencephalopathy (PML) is a rare demyelinating disease of the central nervous system that has been reported as rare adverse drug reaction (ADR) of immunosuppressive drugs. We aimed to study signals of PML for immunosuppressants using a disproportionality analysis of spontaneous adverse event reports.

Methods

Within the US Adverse Event Reporting System, we analyzed all reports of ADRs submitted to the US Food and Drug Administration between January 1, 2004 and September 30, 2010. We used univariate and multivariate logistic regression analysis to calculate reporting odds ratios with 95% confidence intervals of PML for immunosuppressants according to the Anatomical Therapeutic Chemical classification system (L04), rituximab and cyclophosphamide compared to all other drugs.

Results

We identified 635 PML cases in a total of 1 978 706 patients eligible for analysis. Altogether, 21 out of 36 analyzed immunosuppressants were reported at least once with PML. In the univariate analyses, we found a signal for 11 of these drugs (azathioprine, cyclosporine, cyclophosphamide, efalizumab, leflunomide, methotrexate, mycophenolate mofetil, natalizumab, rituximab, tacrolimus and sirolimus). In the multivariate analysis, the signal was no longer present for sirolimus, leflunomide and methotrexate.

Discussion

Our study revealed signals of PML for a substantial number of immunosuppressants, including some drugs less considered so far as a risk factor of PML, especially when used for the treatment of autoimmune disorders. These drugs and possible interactions between different immunosuppressants should be studied more closely in future studies. Copyright © 2012 John Wiley & Sons, Ltd.
On the electrospinning of PVDF: influence of the experimental conditions on the nanofiber properties
Authors: Cozza Erika Simona , Monticelli Orietta , Marsano Enrico , Cebe Peggy
Published: July 2012

The characteristics of poly(vinylidene fluoride) (PVDF) nanofibers, prepared by applying the electrospinning technique from N,N‐dimethylformamide/acetone mixtures, were studied by varying the experimental conditions. The nanofiber morphology was assessed by scanning electron microscopy, while wide angle X‐ray diffraction and infrared spectroscopy were performed to study the crystallinity. The influence of the electrospinning conditions, such as kind of solvent mixture, polymer concentration, voltage tension, airflow and humidity, on nanofiber morphology was studied. In particular, the latter parameter, generally not considered, was found to modify the electrospun mat structure in a relevant way. Generally, the above technique turns out to be capable of strongly affecting the polymorphism of the polymer, namely β phase formation was higher in the electrospun mats compared with cast films, which displayed a non‐polar α crystal phase. As far as the influence of the electrospinning conditions on PVDF crystal structure is concerned, modification of the experimental parameters did not affect the α/β ratio. Nevertheless, comparing the behavior of two commercial PVDF samples with similar molecular masses, our results show that the polymer which forms a higher content of β phase in its cast films allowed electrospun mats characterized by almost complete formation of β phase to be obtained. Copyright © 2012 Society of Chemical Industry
Targeted glycomics by selected reaction monitoring for highly sensitive glycan compositional analysis
Authors: Zhang Hongquan , Wang Zhaohui , Stupak Jacek , Ghribi Othman , Geiger Jonathan D. , Liu Qing Yan , Li Jianjun
Published: July 2012

The development of glycomics increasingly requires the detection and quantification of large numbers of glycans, which is only partially achieved by current glycomics approaches. Taking advantage of selected reaction monitoring to enhance both sensitivity and selectivity, we report here a strategy termed targeted glycomics that enables highly sensitive and consistent identification and quantification of diverse glycans across multiple samples at the same time. In this proof‐of‐principle study, we validated the method by analyzing global N‐glycans expressed in different systems: single proteins, cancer cells, and serum samples. A dynamic range of three orders of magnitude was obtained for the detection of all five glycans released from ribonuclease B. The limit of detection of 80 attomole for Man9GlcNAc2 demonstrated the excellent sensitivity of the method. The capability of the strategy to identify diverse glycans was demonstrated by identification and detection of 162 different glycans and isomers from pancreatic cancer cells. The sensitivity of the method was illustrated further by the ability to detect eight glycans from 250 cancer cells and five glycans released from 100 cancer cells. In serum obtained from rabbits fed control diet or diet enriched with 2% cholesterol, differences to 42 glycans were accurately measured and this indicates that this strategy might find use in studies of biomarker discovery and validation.
Unusual aspects of ion‐pairing effects in room temperature ionic liquids
Authors: Bhat Mohsin Ahmad , Konar Arkaprabha , Ingole Pravin P. , Pandith Altaf Hussain
Published: July 2012

Herein, we report our observations on voltammetric investigations about the redox behaviour of para‐nitrotoluene, 1,4‐benzoquinone and ferrocene, aimed at exploring the unusual aspects of ion‐pairing phenomena in imidazolium‐based room temperature ionic liquids (RTILs). Our observations indicate that the stabilization of electrogenerated ion/radical ion intermediates depends upon the potential of the working electrode and the overall composition of RTILs. In light of observed relative trends and quantum mechanical calculations, we propose that the ion‐pair stabilization of electrogenerated charged species in RTILs is closely related to the structural organization and composition of electrode/RTIL interface. Copyright © 2012 John Wiley & Sons, Ltd.
The equilibrium and kinetics of intermolecular hydrogen bonding in nitroarene anion radical–alcohol system: 1,3‐dinitro‐benzene anion radical – R–OH (R═CH3–, C2H5–, (CH3)2 CH–)
Authors: Mohammad Mahboob , Rauf Asma , Rauf Saba , Tariq Muhammad
Published: July 2012

To explore the possibility of hydrogen bonding of a stable anion radical with DNA – component sugar, hormones, steroid, and so on (through hydroxyl group), as a first step, the possibility of hydrogen bonding of 1,3‐dinitrobenzene anion radical (1,3‐DNB−•) with aliphatic alcohols was studied. It was found that 1,3‐DNB−• anion radical undergoes hydrogen bonding with alcohols: methanol, ethanol, and 2‐proponal. The hydrogen‐bonding equilibrium constant Keq and the (hydrogen‐bonding) rate constants k2 were evaluated through the use of linear scan and cyclic voltammetry theory and techniques. The Keq was found to be in the range of 1.4–6.0 m−1, whereas the rate constants k2 were found to be in the range of 1.5–3.6 m−1 s−1, depending upon the hydrogen‐bonding agent and the equation used for the calculation of the rate constants. The hydrogen‐bonding number n was found to be around 0.5 or 1.0. The implication of this study in, for example, the replication of DNA, the prevention of the formation of super oxide, and so on is discussed. Copyright © 2012 John Wiley & Sons, Ltd.
Isolation of π‐conjugated system through polyfluorene from electronic coupling with side‐chain substituents by cardo structures
Authors: Yeo Hyeonuk , Tanaka Kazuo , Chujo Yoshiki
Published: July 2012

The electronic coupling via the cardo structure in polyfluorene (PFs) was investigated. The series of fluorene units alternatively having alkoxyphenyl as an electron‐donating group (EDG) and/or alkyl benzoate as an electron‐withdrawing group (EWG) at the cardo carbon were synthesized. From the investigation of optical properties of the polymers containing these fluorene units, it was found that the electronic states of the substituents at the cardo carbons and the PF main chains should be less influenced by the introduction of EDG and/or EWG at the cardo structure. Furthermore, these preservation effects in the cardo‐PFs were observed in the film states even after the thermal treatment. We conclude that the electronic structures of the PF main chain are highly preserved from the correlations with the substituents at the cardo carbons. This is the first example, to the best of our knowledge, to survey the systematic information on the electronic structures of the cardo‐PFs and offer the preservation effect of the optical properties from the introduction of EDGs and EWGs at the cardo carbon. © 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2012
Isotropic–nematic phase separation and demixing in mixtures of spherical nanoparticles with length‐polydisperse nanorods
Authors: Green Micah J.
Published: July 2012

An extension of Onsager theory is developed to simulate isotropic–nematic phase separation in a mixture of spheres with length‐polydisperse system of rods. This work is motivated by recent experimental data on nanorod liquid crystals. Prior theoretical investigations indicate that both polydispersity and the presence of spheres should increase the biphasic–nematic phase transition, that is, the nematic cloud point. Results indicate that the phase diagrams undergo drastic changes depending upon both particle geometry and rod length polydispersity. The key geometric factor is the ratio between the sphere diameter and the rod diameter. In general, length fractionation is enhanced by the addition of spheres, which may be experimentally advantageous for separating short nanorods from a polydisperse population. Simulation results also indicate that the nematic cloud and shadow curves may cross one another because of the scarcity of spheres in the shadow phase. In general, these results do indicate that the nematic cloud point increases as a function of sphere loading; however, in certain areas of phase space, this relationship is nonmonotonic such that the nematic cloud point may actually decrease with the addition of spheres. This work has application to a wide range of nanoparticle systems, including mixtures of spherical nanoparticles with nanorods or nanotubes. Additionally, a number of nonspherical particles and structures may behave as spheres, including crumpled graphene and tightly coiled polymers. © 2012 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys, 2012
Promoting consultation recording practice in oncology: identification of critical implementation factors and determination of patient benefit
Authors: Hack Thomas F. , Ruether J. Dean , Weir Lorna M. , Grenier Debjani , Degner Lesley F.
Published: July 2012

Objective

The objectives of this implementation study were to (i) address the evidentiary, contextual, and facilitative mechanisms that serve to retard or promote the transfer and uptake of consultation recording use in oncology practice and (ii) follow patients during the first few days following receipt of the consultation recording to document, from the patient's perspective, the benefits realized from listening to the recording.

Methods

Nine medical and nine radiation oncologists from cancer centers in three Canadian cities (Calgary, Vancouver, and Winnipeg) recorded their primary consultations for 228 patients newly diagnosed with breast (n = 174) or prostate cancer (n = 54). The Digital Recording Use Semi‐Structured Interview was conducted at 2 days and 1 week postconsultation. Each oncologist was provided a feedback letter summarizing the consultation recording benefits reported by their patients.

Results

Sixty‐nine percent of patients listened to at least a portion of the recording within the first week following the consultation. Consultation recording favorableness ratings were high: 93.6% rated the intervention between 75 and 100 on a 100‐point scale. Four main areas of benefit were reported: (i) anxiety reduction; (ii) enhanced retention of information; (iii) better informed decision making; and (iv) improved communication with family members. Eight fundamental components of successful implementation of consultation recording practice were identified.

Conclusions

Further randomized trials are recommended, using standardized measures of the patient‐reported benefit outcomes reported herein, to strengthen the evidence base for consultation recording use in oncology practice. Copyright © 2012 John Wiley & Sons, Ltd.
Respiratory function at age 8–9 after extremely low birthweight or preterm birth in Victoria in 1997
Authors: Hacking Douglas F. , Gibson Anne‐Marie , Robertson Colin , Doyle Lex W. ,   for the Victorian Infant Collaborative Study Group (VICS)
Published: July 2012

To determine if respiratory function at 8 years of age in extremely low birth weight (ELBW; birth weight <1,000 g) or extremely preterm (EPT, <28 weeks' gestation) children born in 1997 remains worse than normal birth weight (NBW; birth weight, >2,499 g) and term (37–42 weeks) controls, particularly in those ELBW/EPT children who had bronchopulmonary dysplasia (BPD). This was a cohort study of 201 consecutive ELBW/EPT survivors born in the state of Victoria during 1997, and 199 contemporaneous randomly selected NBW/term controls. Respiratory function was measured at 8 years of age according to standard guidelines, and compared with previous cohorts born in 1991–1992. Respiratory function data were available for almost 75% of both cohorts. ELBW/EPT subjects had substantial reductions in airflow compared with controls (e.g., mean difference in forced expiratory volume in 1 sec [FEV1] −0.91 SD, 95% confidence interval [CI] −1.19 to −0.63 SD, and in maximum expiratory flow between 25% and 75% of vital capacity [FEF25–75%] −0.96 SD, 95% CI −1.22 to −0.71). These differences were similar to those observed between ELBW/EPT and controls subjects born in 1991–1992. Within the ELBW/EPT cohort, children who had BPD in the newborn period had significant reductions in both the FEV1 (−0.76 SD) and FEF25–75% (−0.58 SD) compared with those who did not have BPD, which were not statistically significant from those in the 1991–92 cohort. ELBW/EPT children born in 1997 still have significantly abnormal lung function compared with NBW/term controls, but results were similar to an earlier era when survival rates were lower. Pediatr Pulmonol. 2013; 48:449–455. © 2012 Wiley Periodicals, Inc.
Usefulness of impulse oscillometry and fractional exhaled nitric oxide in children with Eosinophilic bronchitis
Authors: Kim Yoon Hee , Kim Kyung Won , Baek Jiyoung , Park Hyun Bin , Kim Hyemi , Song Kyung‐Joo , Lee Jae Myun , Sohn Myung Hyun , Kim Kyu‐Earn
Published: July 2012

Background

Eosinophilic bronchitis (EB) is a common cause of chronic cough. Although EB shares many immunopathologic features with asthma, it does not show airway hyperresponsiveness or reversible airway obstruction by spirometry.

Objective

Compared to healthy children without pulmonary disease, we hypothesized that EB patients would demonstrate abnormal pulmonary function and inflammation with impulse oscillometry (IOS) and fractional exhaled nitric oxide (FeNO), which are more sensitive tests of these parameters than spirometry.

Methods

A total of 232 children with asthma, 109 with EB, and 115 control subjects were enrolled. We compared pulmonary function parameters and FeNO levels among the three groups. Additionally, we designated a screening cutoff value of FeNO combined with IOS parameters to distinguish EB from the control group, and identify which children with EB have more asthmatic characteristics.

Results

By IOS, the bronchodilator response of the EB and asthma groups increased significantly compared to controls for both reactance at 5 Hz (Δ X5) and reactance area (Δ AX) (P < 0.0001). Cutoff values to distinguish EB from controls were a Δ X5 of −20% (sensitivity, 77.5%; specificity, 49.6%), and Δ AX of −30% (sensitivity, 75.0%; specificity, 46.0%), when the FeNO is 20 ppb.

Conclusions

Reversible airway obstruction in IOS and elevated FeNO levels can be detected in children with EB. This would support that EB in children shows airway characteristics similar to those of asthma, and that a continuum exists between asthma and EB. Pediatr Pulmonol. 2013; 48:221–228. © 2012 Wiley Periodicals, Inc.
Classic kaposi sarcoma with pulmonary involvement mimicking endobronchial tuberculosis in a child
Authors: Cakir Fatma B. , Cakir Erkan , Tuzuner Nukhet , Kut Arif
Published: July 2012

Kaposi' sarcoma (KS) is a low‐grade vascular neoplasm and classic KS, a subtype of KS, is extremely rare in children. Childhood pulmonary involvement in classic KS has not been reported in the literature. We describe an HIV‐seronegative pediatric case with a fulminant course of classic KS with pulmonary involvement mimicking endobronchial tuberculosis. Pediatr Pulmonol. 2013; 48:310–312. © 2012 Wiley Periodicals, Inc.
How to get proteomics to the clinic? Issues in clinical proteomics, exemplified by CE‐MS
Authors: Mischak Harald
Published: July 2012

Clinical proteomics is defined as application of proteome analysis aiming at improving the current clinical situation. As such, the success of clinical proteomics should be assessed based on the clinical impact following implementation of the findings. While we have experienced significant technological advancements in mass spectrometry in the last years, based on the above measure, this has not at all resulted in similar advancements in clinical proteomics. Although a large number of proteomic biomarkers have been described, most of them were not subsequently validated, and certainly have had no impact in clinical decision making as yet. Under the current conditions, it appears likely that the situation will not change significantly: we will be flooded by reports on biomarkers, but not see any implementation. In this article, some key issues in proteomic biomarker research are pinpointed, based on the experience with CE‐MS, likely also holding true for biomarkers resulting from other analysis domains.
Electrodeposition of a Pt–PrO2−x electrocatalyst on diamond electrodes for the oxidation of methanol
Authors: Chen Liang , Hu Jingping , Foord John S.
Published: July 2012

The electrodeposition of Pt–PrO2−x nanostructures on boron‐doped diamond electrodes was explored by decorating platinum nanoparticles with praseodymium oxide, for application as an electrocatalyst in the electrooxidation of methanol in direct methanol fuel cells. A high loading of platinum with good stability was deposited by adopting a two‐stage protocol, which involved a stepped potential route and a chronoamperometric approach. Praseodymium oxide was then coated on the platinum particles from solutions containing praseodymium nitrate and hydrogen peroxide. The porous microstructure of the resulting catalyst was characterized by X‐ray photoelectron spectroscopy and scanning electron microscope, along with electrochemical measurement. The addition of praseodymium oxide to the Pt resulted in a higher catalytic activity profile for methanol oxidation along with an improved resistance to poisoning effects caused by incompletely oxidized carbonaceous species.
Etch‐pit formation mechanism induced on HPHT and CVD diamond single crystals by H2/O2 plasma etching treatment
Authors: Naamoun M. , Tallaire A. , Silva F. , Achard J. , Doppelt P. , Gicquel A.
Published: July 2012

H2/O2 plasma treatments offer advantages over other etching processes of diamond as a technique to prepare the substrate surface prior to chemical vapor deposition (CVD) diamond growth. It allows removing defects induced on the surface by polishing, thus leading to an improved morphology and limiting the stress within the grown crystal. Moreover, they present the advantage to be performed in situ just before the CVD diamond growth. In this work, H2/O2 plasma treatments were performed so that threading dislocations and other defects are etched preferentially, thus leaving typical etch‐pits. The defect densities in several high pressure high temperature (HPHT) and CVD diamond crystals were then quantified and compared; in particular defects originating from polishing could be distinguished from extended defects inside the crystal. Furthermore, the defect density was found to be of the order of 105/cm2 for HPHT crystals, which was approximately one order of magnitude lower than that measured in low cost commercial CVD monocrystals. The use of laser microscopy also allowed observing the morphology, size and depth of different etch‐pits of 〈001〉‐oriented and misoriented crystals and their evolution with etching time in order to get a better understanding of defect density and formation during CVD growth.
Luminescence of defects and breakdown sites in multicrystalline silicon solar cells
Authors: Mankovics D. , Klossek A. , Krause Ch. , Arguirov T. , Seifert W. , Kittler M.
Published: July 2012

We studied the correlation between the appearance of defects and of breakdowns in fully processed solar cells by electroluminescence imaging. Images under forward and reverse bias were recorded, revealing defective areas and breakdown sites of the cells, respectively. In the experiments presented here an InGaAs camera system was used, which allows us to detect short wave infrared light in the 900–1700 nm range. Applying a forward bias the band‐to‐band luminescence (1.1 eV/1150 nm) and the defect‐related luminescence (0.8 eV/1550 nm) were imaged. Both imaging techniques reveal mainly dislocation‐rich areas and grain boundaries. Applying a reverse bias (approximately −10 V), breakdown luminescence occurs. It was found that the distribution of the breakdown sites across the solar cells is different from the distribution of the defects showing luminescence at 0.8 eV (grain boundaries, dislocations). The spatial separation between those defects and the breakdown sites was clearly evidenced by high resolution imaging. Possible reasons for such spatial separation are discussed.
A re‐examination of cobalt‐related defects in n‐ and p‐type silicon
Authors: Scheffler Leopold , Kolkovsky Vladimir , Weber Jörg
Published: July 2012

In the present work cobalt‐doped n‐ and p‐type silicon samples were studied by means of deep level transient spectroscopy (DLTS) and Laplace‐DLTS (LDLTS). We demonstrate that two dominant DLTS peaks previously assigned to a substitutional Co defect have different annealing behaviour and therefore belong to different defects. After wet chemical etching three other peaks (E90, E140 and H160) were observed in the samples. The intensity of the peaks becomes larger in the H‐plasma treated samples. This together with depth profiling demonstrates that the peaks are hydrogen‐related defects. The origin of the peaks will be discussed.
Electrospray ionisation mass spectrometric studies for the determination of palladium after pre‐concentration by disposable pipette extraction
Authors: Jaison P. G. , Kumar Pranaw , Telmore Vijay M. , Aggarwal Suresh K.
Published: July 2012

RATIONALE

Electrospray ionisation mass spectrometric (ESI‐MS) analysis of Pd in complex matrices is difficult due to the multiplicity of matrix effects. Two different approaches, internal standard and matrix separation, were investigated for developing a reliable analytical procedure for the trace level determination of Pd in simulated high‐level liquid waste (SHLLW) solutions.

METHODS

An ESI mass spectrometer with a quadrupole‐time‐of‐flight analyser was used to study the speciation of the palladium‐benzoylthiourea (Pd‐BTU) complex and to determine the Pd content. The Pd‐BTU complex was selectively pre‐concentrated using disposable pipette extraction (DPX). Extraction parameters as well as ESI‐MS parameters such as concentration of BTU, acidity, composition of medium and capillary voltage, etc., were optimized based on the major species [Pd(BTU)2S]+.

RESULTS

The method gave quantitative and selective pre‐concentration of the Pd‐BTU complex from SHLLW. Linearity from 5 ppb to 200 ppb and a limit of detection of 0.012 ppb were obtained for Pd. No interference from the neighboring elements, viz. ruthenium, rhodium, silver and cadmium, was observed during the determination of Pd based on the [Pd(BTU)2S]+peak. The ESI signal intensity was not influenced by the presence of the many other elements in the SHLLW solution.

CONCLUSIONS

Good sensitivity, tolerance to matrix concentration and the absence of interference from neighboring elements make the method very promising for the determination of Pd at low levels in complex samples. We have demonstrated the capability of ESI‐MS for the quantification of Pd in complex matrices and its potential for providing data on speciation, using the Pd‐BTU complex. Copyright © 2012 John Wiley & Sons, Ltd.
Characterization of lipid A profiles from Shigella flexneri variant X lipopolysaccharide
Authors: Casabuono Adriana C. , van der Ploeg Claudia A. , Rogé Andrés D. , Bruno Susana B. , Couto Alicia S.
Published: July 2012

RATIONALE

In developing countries, Shigella flexneri (Sf) is the major causative agent of the endemic shigellosis (bacillary dysentery) responsible annually for one million fatalities mostly among infants. Lipopolysaccharides (LPSs) are characteristic components of the outer membrane of the overwhelming majority of Gram‐negative bacteria. Since lipid A is essential for the viability of the Gram‐negative bacteria, it is subject to extensive chemical studies with new analytical techniques.

METHODS

Lipid A was released by mild acid hydrolysis from the lipopolysaccharide which was obtained via the phenol/water extraction, purified and analyzed by matrix‐assisted laser desorption/ionization time‐of‐flight mass spectrometry (MALDI‐TOF‐MS) and matrix‐assisted laser desorption/ionization laser‐induced dissociation tandem mass spectrometry (MALDI‐LID‐MS/MS).

RESULTS

A detailed structural study of the whole lipid A obtained from S. flexneri variant X was carried out for the first time. Thus, we have shown that lipid A is a heterogeneous mixture having different numbers of acylated and phosphoethanolamine groups attached to the diglucosamine backbone. Furthermore, we found in the phenol phase an unusual hepta‐acylated lipid A species, although the abundance was very low.

CONCLUSIONS

MALDI‐TOF‐MS allowed us to unravel the lipid A heterogeneity, which was not previously reported in Sf LPS. It is well known that slight variations of the chemical structure of lipid A may change its biological activity. Thus, the knowledge of the detailed chemical structure represents an essential step for further development of new preventive or therapeutically active compounds. Copyright © 2012 John Wiley & Sons, Ltd.
Identification, quantification and carbon stable isotopes determinations of organic acids in monofloral honeys. A powerful tool for botanical and authenticity control
Authors: Daniele Gaëlle , Maitre Dany , Casabianca Hervé
Published: July 2012

RATIONALE

The analytical composition and botanical origin of honey are basic data used to determine the quality of this foodstuff. Although proteins are used to characterise the analytical composition of honey, they can be eliminated during its ultrafiltration and, in the case of honeys not saturated with their own pollen, the use of proteins does not work well. As acidity is a well‐known characteristic of honey and organic acids are present at around 0.5% in honey, we therefore investigated an alternative method to the protein‐based White method, using organic acids as new internal standards instead of proteins.

METHODS

The qualitative and quantitative analyses of 14 organic acids were carried out by ion chromatography with an electrochemical detector. The 13C/12C isotopic ratios of the honeys, and of the organic acids extracted from them with an anion exchange resin, were determined by isotope ratio mass spectrometry.

RESULTS

Gluconic acid is the predominant organic acid in honey, at between 1.8 and 12.7 g/kg. For fir honey the major acid is galacturonic acid at around 4.6 g/kg. The isotopic ratios of honeys and of their acids are strongly linked. Correlations between the δ13C values of the honey and the acids were significant, and better than those obtained using proteins.

CONCLUSIONS

This study has provided a method to differentiate honeys from seven botanical origins, based on organic acid analysis. By combining various organic acid contents and isotopic ratio values through statistical processing by Principal Component Analysis it is possible to differentiate honey samples as a function of their botanical origin. Copyright © 2012 John Wiley & Sons, Ltd.
Development of liquid chromatography/mass spectrometry based screening assay for PfTrxR inhibitors using relative quantitation of intact thioredoxin
Authors: Munigunti Ranjith , Calderón Angela I.
Published: July 2012

RATIONALE

Plasmodium falciparum (Pf) thioredoxin reductase (TrxR) catalyzes the reduction of thioredoxin disulfide (Trx–S2) to thioredoxin dithiol (Trx–(SH)2) that is essential for antioxidant defense mechanism and DNA synthesis in the parasite and is a validated drug target for new antimalarial agents.

METHODS

In this study, we have developed a liquid chromatography/mass spectrometry (LC/MS)‐based functional assay to identify inhibitors of PfTrxR by quantifying the product formed (Trx–(SH)2) in the enzymatic reaction. Relative quantitation of the reaction product (intact Trx–(SH)2) was carried out using an Agilent 6520 QTOF mass spectrometer equipped with a positive mode electrospray ionization (ESI) source.

RESULTS

The calibration curve prepared for Trx–(SH)2 at concentrations ranging from 1.8 to 116.5 µg/mL was linear (R2 >0.998). The limit of detection (LOD) and limit of quantification (LOQ) of Trx–(SH)2 were at 0.45 and 1.8 µg/mL respectively. To validate the developed functional assay we have screened reference compounds 1, 2 and 3 for their PfTrxR inhibitory activity and ten natural compounds (at 10 μM) which were earlier identified as ligands of PfTrxR by a UF‐LC/MS based binding assay.

CONCLUSIONS

The developed LC/MS‐based functional assay for identification of inhibitors of PfTrxR is a sensitive and reliable method that is also amendable for high‐throughput format. This is the first representation of a relative quantitation of intact Trx–(SH)2 using LC/MS. Copyright © 2012 John Wiley & Sons, Ltd.
Structural identification by differential mass spectrometry as a criterion for selecting the best quantum chemical calculation of formation enthalpy for tetrachlorinated biphenyls
Authors: Dinca Nicolae , Covaci Adrian
Published: July 2012

RATIONALE

The assignment of correct structures for isomers with similar mass spectra (e.g. polyhalogenated aromatic compounds) is not always successful when spectral libraries alone are employed or, even worse, when the compounds are not present in commercial spectral libraries.

METHODS

We present a computational method based on differential mass spectrometry (Diff‐MS) for the validation of formation enthalpy (ΔfH) series calculated using quantum chemistry for the fragments produced in electron ionization (EI)‐MS. The method simulates the chemical structure identification (CSI) of isomers with similar mass spectra using differential mass spectra and ΔfH series. The best ΔfH values were those from which the correct structures could be derived.

RESULTS

We have used six tetrachlorinated biphenyl isomers (TeCBs 44, 46, 52, 66, 74, 77). Their EI mass spectra were acquired at 70 eV and, for the principal ions, five series of ΔfH values were computed by the semi‐empirical methods, AM1, MINDO3, MNDO, PM3, and RM1. The generation of differential mass spectra and the correlation with the ΔfH series for the calculation of probabilities from the list of structural assignments were carried out with the ordering algorithm (ORD) of the CSI‐Diff‐MS Data Analysis 3.1.1 program.

CONCLUSIONS

Intelligent software, used for structural elucidation based on MS and QCC, was employed to select the best values of the formation enthalpies of TeCBs. The advantages and disadvantages of the semi‐empirical methods for the calculation of ΔfH values for different TeCB ions are critically presented. The best semi‐empirical methods were RM1, AM1 and MINDO3, which can be used to calculate the ΔfH database necessary to identify TeCB isomers. This approach allowed the correct assignment of structures for isomers with very similar mass spectra and demonstrated the reliability of the correlation between differential mass spectra and the formation enthalpies of the fragment ions. Copyright © 2012 John Wiley & Sons, Ltd.
Fluorescent Silica Nanoparticles Improve Optical Imaging of Stem Cells Allowing Direct Discrimination between Live and Early‐Stage Apoptotic Cells
Authors: Accomasso Lisa , Rocchietti Elisa Cibrario , Raimondo Stefania , Catalano Federico , Alberto Gabriele , Giannitti Andrea , Minieri Valentina , Turinetto Valentina , Orlando Luca , Saviozzi Silvia , Caputo Giuseppe , Geuna Stefano , Martra Gianmario , Giachino Claudia
Published: July 2012

Highly bright and photostable cyanine dye‐doped silica nanoparticles, IRIS Dots, are developed, which can efficiently label human mesenchymal stem cells (hMSCs). The application procedure used to label hMSCs is fast (2 h), the concentration of IRIS Dots for efficient labeling is low (20 μg mL−1), and the labeled cells can be visualized by flow cytometry, confocal microscopy, and transmission electron microscopy. Labeled hMSCs are unaffected in their viability and proliferation, as well as stemness surface marker expression and differentiation capability into osteocytes. Moreover, this is the first report that shows nonfunctionalized IRIS Dots can discriminate between live and early‐stage apoptotic stem cells (both mesenchymal and embryonic) through a distinct external cell surface distribution. On the basis of biocompatibility, efficient labeling, and apoptotic discrimination potential, it is suggested that IRIS Dots can serve as a promising stem cell tracking agent.
Equifinality in Project Management Exploring Causal Complexity in Projects
Authors: Kapsali Maria
Published: July 2012

Surveys reveal that the majority of innovation projects do not achieve their goals and waste resources. Notorious examples are the National Health Service's National Programme for IT project and many multibillion European Union funded projects. Academics and practitioners suggest that this failure is because conventional project management methods fail to capture the serendipitous, evolutionary and experimental nature of complex innovation projects. Results from previous research based on European Union healthcare innovation projects revealed that we need to develop a robust method based on the systems thinking construct of equifinality to understand and manage complex causality in projects. This paper critically evaluates how equifinality has been used in management research, the reasons for the discontinuous application of systems thinking and equifinality and examines the ways to embed equifinality in project management, arguing how holism, control, boundary management and causal complexity are critical to the application of system thinking in project management. Copyright © 2012 John Wiley & Sons, Ltd.
Spatial Domains of Progenitor-Like Cells and Functional Complexity of a Stem Cell Niche in the Neonatal Rat Spinal Cord
Authors: Marichal Nicolás , García Gabriela , Radmilovich Milka , Trujillo-Cenóz Omar , Russo Raúl E.
Published: July 2012

During spinal cord development, progenitors in the neural tube are arranged within spatial domains that generate specific cell types. The ependyma of the postnatal spinal cord seems to retain cells with properties of the primitive neural stem cells, some of which are able to react to injury with active proliferation. However, the functional complexity and organization of this stem cell niche in mammals remains poorly understood. Here, we combined immunohistochemistry for cell-specific markers with patch-clamp recordings to test the hypothesis that the ependyma of the neonatal rat spinal cord contains progenitor-like cells functionally segregated within specific domains. Cells on the lateral aspects of the ependyma combined morphological and molecular traits of ependymocytes and radial glia (RG) expressing S100β and vimentin, displayed passive membrane properties and were electrically coupled via Cx43. Cells contacting the ventral and dorsal poles expressed the neural stem cell markers nestin and/or vimentin, had the typical morphology of RG, and appeared uncoupled displaying various combinations of K+ and Ca2+ voltage-gated currents. Although progenitor-like cells were mitotically active around the entire ependyma, the proliferative capacity seemed higher on lateral domains. Our findings represent the first evidence that the ependyma of the rat harbors progenitor-like cells with heterogeneous electrophysiological phenotypes organized in spatial domains. The manipulation of specific functional properties in the heterogeneous population of progenitor-like cells contacting the ependyma may in future help to regulate their behavior and lineage potential, providing the cell types required for the endogenous repair of the injured spinal cord.
Combined administration of cerebrolysin and donepezil induces plastic changes in prefrontal cortex in aged mice
Authors: Alcántara‐González Faviola , Mendoza‐Perez Claudia Rebeca , Zaragoza Néstor , Juarez Ismael , Arroyo‐García Luis Enrique , Gamboa Citlalli , De La Cruz Fidel , Zamudio Sergio , Garcia‐Dolores Fernando , Flores Gonzalo
Published: July 2012

Cerebrolysin (Cbl) shows neurotrophic and neuroprotective properties while donepezil (Dnp) is a potent acetylcholinesterase (AChE) inhibitor, both drugs are prescribed for Alzheimer's disease (AD) treatment. Previous studies have shown that the Dnp and Cbl administered separately, modify dendritic morphology of neurons in the prefrontal cortex and hippocampus in senile rodents. Since the deficit of neurotrophic factor activity is implicated in the degeneration of cholinergic neurons of basal forebrain, a combination therapy of Dnp and Cbl has been tested recently in Alzheimer's patients. However, the plastic changes that may underlie this combined treatment have not yet been explored. We present here the effect of the combined administration of Cbl and Dnp on dendritic morphology in brain regions related to learning and memory in aged mice. The Golgi‐Cox staining protocol and Sholl analysis were used for studying dendritic changes. Cbl and Dnp were administrated daily for 2 months to 9‐months‐old mice. Locomotor activity was assessed, as well as the dendritic morphology of neurons in several limbic regions was analyzed. Results showed that Cbl and Dnp induced an increase in locomotor activity without synergistic effect. The Cbl or Dnp treatment modified the dendritic morphology of neurons from prefrontal cortex (PFC), dorsal hippocampus (DH), dentate gyrus (DG), and the shell of nucleus accumbens (NAcc). These changes show an increase in the total dendritic length and spine density, resulting in an improvement of dendritic arborization. Prominently, a synergistic effect of Cbl and Dnp was observed on branching order and total dendritic length of pyramidal neurons from PFC. These results suggest that Dnp and Cbl may induce plastic changes in a manner independent of each other, but could enhance their effect in target cells from PFC. Synapse 66:938–949, 2012. © 2012 Wiley Periodicals, Inc.
Teenage employment and career readiness
Authors: Greene Kaylin M. , Staff Jeremy
Published: July 2012

Most American youth hold a job at some point during adolescence, but should they work? This article presents a broad overview of teenage employment in the United States. It begins by describing which teenagers work and for how long and then focuses attention on the consequences (both good and bad) of paid work in adolescence. It then presents recent nationally representative data from the Monitoring the Future Study suggesting that limited hours of paid work do not crowd out developmentally appropriate after‐school activities. A review of the literature also supports the idea that employment for limited hours in good jobs can promote career readiness and positive development. The article concludes with a discussion of the implications of youth work for practitioners and policymakers who are delivering career‐related programming.
What schools are doing around career development: Implications for policy and practice
Authors: Perry Justin C. , Wallace Eric W.
Published: July 2012

This article describes the role that schools are playing in supporting career development for young people. It examines the history of career‐related programming in schools, including school‐to‐work programs, career and technical education, the college and career readiness movement, and current school reform initiatives. This understanding of schools' history, roles, opportunities, and constraints can help practitioners and policymakers think about how to build a system that supports youth development.
Supporting vocationally oriented learning in the high school years: Rationale, tasks, challenges
Authors: Halpern Robert
Published: July 2012

This article highlights the limitations of our current educational system in terms of vocational learning and highlights the role that vocational learning can play in supporting youth development and improving youth outcomes. It discusses the role that nonschool settings can play in supporting vocational learning and suggests strategies to improve our in‐school and out‐of‐school systems to build a more coherent whole that promotes youth development across various settings.
Next steps for research and practice in career programming
Authors: Hynes Kathryn
Published: July 2012

The articles in this volume of New Directions for Youth Development highlight the broad research base relevant to career programming from which policy and practice can draw. This concluding article integrates these findings to highlight next steps for research and practice related to career programming.
A non-renormalization theorem for chiral primary 3-point functions
Authors: Baggio Marco , de Boer Jan , Papadodimas Kyriakos
Published: July 2012

Abstract

In this note we prove a non-renormalization theorem for the 3-point functions of 1/2 BPS primaries in the four-dimensional
$ \mathcal{N} = 4 $
SYM and chiral primaries in two dimensional
$ \mathcal{N} = \left( {4,4} \right) $
SCFTs. Our proof is rather elementary: it is based on Ward identities and the structure of the short multiplets of the superconformal algebra and it does not rely on superspace techniques. We also discuss some possible generalizations to less supersymmetric multiplets.