bluuebunny/crossref_metadata_2025 huggingface dataset:
Molecular analysis and protein processing in late‐onset pompe disease patients with low levels of acid α‐glucosidase activity
Authors: Bali Deeksha S. , Tolun Adviye A. , Goldstein Jennifer L. , Dai Jian , Kishnani Priya S.
Published: April 2011

Introduction:

Pompe disease (glycogen storage disease type II, acid maltase deficiency) is caused by deficiency of lysosomal acid α‐glucosidase (GAA). A few late‐onset patients have been reported with skin fibroblast GAA activity levels of <2%.

Methods:

We measured GAA activity in skin fibroblasts from 101 patients with late‐onset Pompe disease. Whenever possible, we performed Western blot analysis and correlated the results with GAA activity and GAA gene mutations.

Results:

Thirteen patients (13%) had skin fibroblast GAA activity of <1% of normal. Although there was wide genetic heterogeneity, none of these patients carried the common late‐onset mutation c.‐32‐13T>G. We performed Western blot on 11 patients with <1% GAA activity. All produced GAA protein that was at lower levels and/or was abnormally processed.

Discussion:

There is no common mutation associated with <1% GAA activity in late‐onset Pompe disease patients. Most patients produce unprocessed forms of GAA protein compared with patients with higher GAA activity. Muscle Nerve, 2011
Onset and spreading patterns of upper and lower motor neuron symptoms in amyotrophic lateral sclerosis
Authors: Körner Sonja , Kollewe Katja , Fahlbusch Marion , Zapf Antonia , Dengler Reinhard , Krampfl Klaus , Petri Susanne
Published: April 2011

Introduction

The potential linkage between upper (UMN) and lower motor neuron (LMN) involvement in amyotrophic lateral sclerosis (ALS) has not yet been fully elucidated. There is ongoing discussion as to whether ALS is primarily a disease of UMNs or LMNs.

Methods

We performed a retrospective analysis of 189 ALS patients from our ALS outpatient database to investigate the different spreading patterns of UMN and LMN affection in disease progression in relation to the onset region.

Results

The body region with the highest UMN involvement at onset in general also had the highest frequency of LMN signs and vice versa. This is in line with the hypothesis of a focal onset of disease, which then spreads to adjacent areas. However, there was a great variation between ALS phenotypes.

Discussion

These observations support the hypothesis of focal damage of a localized group of motor neurons, which then spreads to adjacent motor neurons. Muscle Nerve, 2011
Changes in muscle T2 and tissue damage after downhill running in mdx Mice
Authors: Mathur Sunita , Vohra Ravneet S. , Germain Sean A. , Forbes Sean , Bryant Nathan D. , Vandenborne Krista , Walter Glenn A.
Published: April 2011

Introduction:

In this study we compared the effects of downhill or horizontal treadmill running on the magnetic resonance imaging (MRI) transverse relaxation time constant (T2) in mdx mice.

Methods:

Mice underwent either downhill (n = 11 mdx, n = 6 controls) or horizontal running (n = 9, mdx only) on a treadmill. MRI was conducted prior to exercise, immediately afterward (∽20 minutes), and then 24 and 48 hours after exercise.

Results:

A higher percentage of pixels with elevated T2 in the lower hindlimb muscles was observed in the mdx mice compared with controls both pre‐exercise (P < 0.001) and at each time‐point after downhill running (P < 0.05), but not with horizontal running. The medial compartment muscles appeared to be the most susceptible to increased T2.

Conclusions:

Downhill running provides a stimulus for inducing acute changes in muscle T2 in mdx mice. MRI is a non‐invasive approach for examining acute muscle damage and recovery in multiple muscle groups simultaneously. Muscle Nerve, 2010.
Macrophages: A minimally invasive tool for monitoring collagen VI myopathies
Authors: Gualandi Francesca , Curci Rosa , Sabatelli Patrizia , Martoni Elena , Bovolenta Matteo , Maraldi Mario N. , Merlini Luciano , Ferlini And Alessandra
Published: April 2011

Introduction: Collagen VI expression was tested in peripheral blood macrophages from patients with collagen VI–related myopathies and compared with muscle biopsy. Methods: RNA and protein studies were performed in blood macrophages from 5 patients previously diagnosed with either Ullrich congenital muscular dystrophy (UCMD) or Bethlem myopathy (BM). The full spectrum of possible genotypes was considered, including both dominant and recessive UCMD and BM cases. Results: In the dominant BM patient, no collagen VI alterations were detectable in macrophages or muscle biopsy. In the remaining patients, the protein defect caused by the selected mutations, as well as the transcriptional abnormalities, were readily detectable in macrophages, at levels comparable to those observed in muscle biopsy samples and cultured skin fibroblasts. Conclusions: Our data support the suitability of peripheral blood macrophages as a reliable, minimally invasive tool for supplementing or replacing muscle/skin biopsies in the diagnosis and monitoring of collagen VI–related myopathies. Muscle Nerve 44: 80–84, 2011.
Multiple enlarged nerves on neurosonography: An unusual paraneoplastic case
Authors: Leypoldt Frank , Friese Manuel A. , Böhm Josef , Bäumer Tobias
Published: April 2011

Multiple nerve enlargements at non‐entrapment sites are usually caused by hereditary or acquired immune‐mediated neuropathies.We describe a case of multifocal hypertrophic mononeuropathies detected by nerve sonography with a clinical picture of progressive mononeuritis multiplex caused by a paraneoplastic syndrome associated with anti‐Hu antibodies. This case illustrates an unusual but important paraneoplastic differential diagnosis of progressive multifocal hypertrophic neuropathies. It emphasizes the role of nerve ultrasound in the diagnostic work‐up of peripheral nervous system disorders. Muscle Nerve, 2011
High prevalence of abnormal glucose regulation in patients presenting for routine coronary angiography
Authors: English CL , Hastings J , Hennessy S , Dinneen SF , Crowley J
Published: April 2011

Abnormal glucose metabolism is a known risk factor for coronary artery disease (CAD) and is frequently unrecognised even in patients with acute coronary syndrome. Patients with stable coronary symptoms frequently have multiple risk factors and may have no assessment of glucose regulation. The purpose of this study was to assess the prevalence of impaired glucose tolerance (IGT) and diabetes mellitus (DM) in a group of patients with stable symptoms presenting for coronary angiography.

A modified oral glucose tolerance test (OGTT) was performed on 182 unselected patients undergoing elective angiography. Patients with known DM were excluded. Demographic data including cardiovascular risk factors, body mass index (BMI), and history of CAD were recorded.

In all, 182 patients with a mean age of 62.1 years (±10.7 years) were studied. Indications for angiography were suspected angina. By WHO criteria an abnormal two‐hour glucose was present in 49% of individuals, with 10.4% of these patients having overt DM. An abnormal two‐hour glucose was seen in 63.2% of patients with significant CAD compared with 40.3% with normal or insignificant disease (p=0.004); 48.9% of patients with IGT or DM had normal fasting plasma glucose (FPG). In 78% of patients, BMI was over 25kg/m2.

In this high risk population with multiple risk factors for CAD, previously undetected IGT and overt DM are very common. Almost two‐thirds of patients with significant CAD had abnormal glucose regulation. The use of an FPG test alone may miss a significant number of patients with unrecognised glucose intolerance. Copyright © 2011 John Wiley & Sons.
‘Doing Diabetes’: an evaluation of communication skills and behaviour change training for health professionals
Authors: Swanson V , Gold A , Keen A
Published: April 2011

Good communication skills enhance consultations between health professionals and patients, leading to better patient outcomes and increased satisfaction. Health professionals working in diabetes can find it difficult to understand patients' apparent self‐management ‘failures’, but may lack psychological skills to support efforts at behaviour change. This paper reports on the impact of three‐day workshops using evidenced psychological theory as a basis for promoting communication and behaviour change skills in health professionals working in diabetes.

Workshops were delivered in seven urban or rural health service areas in Scotland by a multidisciplinary team. Each included three full‐day sessions two weeks apart, and used a range of theoretically‐underpinned and evidenced teaching and learning methods. Eighty‐one health professionals working in diabetes care participated. Pre‐and post‐evaluations utilised questionnaires with closed and open questions.

Participants recorded a significant increase in ‘positive’ communication and behaviour change techniques and a decrease in ‘negative’ techniques over the three workshops. Improved communication and behaviour change skills were perceived as having a positive impact on their understanding of patients' motivations and on their own day‐to‐day practice.

In conclusion, communication and behaviour change skills are very important tools for health professionals working in diabetes care. They can be taught effectively in relatively few sessions using theoretically‐based and evidenced approaches, and have a perceived benefit in relation to enhancing patient care and professionals' satisfaction with clinical practice. Copyright © 2011 John Wiley & Sons.
Psychological insulin resistance: a critical review of the literature
Authors: Gherman A , Veresiu IA , Sassu RA , Schnur JB , Scheckner BL , Montgomery GH
Published: April 2011

Our objective was to conduct a critical review of the factors that account for psychological insulin resistance (PIR) and of the available strategies to reduce it.

Medline, PubMed, Cochrane reviews, PsycInfo, ProQuest, Science Direct, and EBSCO databases were searched and 60 studies were included in the final review. Topics reviewed included: research methods, instruments to assess PIR, PIR in patients and in the medical care team, and proposed strategies for overcoming it.

The results showed that a large number of factors account for PIR in patients. The main categories are emotional, cognitive, social/cultural, and interaction with health providers. Physicians mainly delay insulin because they lack knowledge on guidelines or pancreas physiology, they fear inducing hypoglycaemia in elderly or impaired patients, and/or they lack time or personnel resources to teach initiation. Strategies proposed to reduce PIR are educational and psychological (exposure, desensitisation, relaxation and counselling).

We concluded that there is a great need of evidence‐based interventions that help remove psychological barriers about insulin use in patients, as well as in health care providers. Copyright © 2011 John Wiley & Sons.
Diabetic cystopathy: do we recognise this in our patients?
Authors: Jose B , Karampini E , Pucci M , Burbridge W , Irwin S , De P
Published: April 2011

A 44‐year‐old South Asian woman, with type 2 diabetes requiring insulin, presented with multiple syncopal episodes. Her diabetes was complicated by peripheral neuropathy, diabetic retinopathy and nephropathy. She also had features of autonomic neuropathy. Short synacthen test ruled out adrenal insufficiency; thyroid function was normal. HbA1c was elevated at 14.6% (136mmol/mol). Abdominal computed tomography showed grossly dilated bladder (9.5cm x 14cm x 17.5cm), compressing the mid‐ureter. The size suggested an on‐going chronic process, consistent with diabetic cystopathy.

An indwelling urethral catheter relieved the bladder distension and the patient was later successfully educated to void the bladder by the clock rather than bladder sensation. Euglycaemia was achieved with twice‐daily pre‐mixed analogue insulin.

Diabetic cystopathy is an under‐diagnosed complication of diabetes. Most contemporary investigators believe that the aetiology is multifactorial, including disturbances of the bladder detrusor muscle, urethra, autonomic nerves and perhaps the urothelium. This most troublesome of all the genitourinary complications of diabetes is often overlooked. Copyright © 2011 John Wiley & Sons.
Design, synthesis and characterization of a novel self‐doped polyaniline derivative
Authors: Liu Hongtao , Chao Danming , Liu Xincai , Jia Xiaoteng , He Libing , Cui Lili , Yao Lei , Wang Ce
Published: April 2011

A type of self‐doped polyaniline derivative was successfully synthesized using an oxidative coupling polymerization approach. The structure of the electroactive polymer was investigated using Fourier transform infrared and 1H NMR spectroscopy and gel permeation chromatography. Its thermal and spectral properties were characterized using thermogravimetric analysis and UV‐visible spectroscopy. The electrochemical activity of the polymer was studied using cyclic voltammetry (CV) in 1.0 mol L−1 H2SO4 solution with various scan rates. The peak current increases linearly with scan rate from 10 to 120 mV s−1, which indicates that the electrode reaction is controlled by a surface process. In addition, the self‐doped characteristic was investigated using CV in 1.0 mol L−1 KCl solution with pH value changing from 1 to 12, and the results indicate that the polymer has excellent electrochemical activity even in neutral and alkaline environments. Copyright © 2010 Society of Chemical Industry
A modified model of electrical conduction for carbon black–polymer composites
Authors: Yang Jia , Liang Jizhao
Published: April 2011

A modified model of electrical conduction for carbon black‐polymer composites is proposed based on the general effective media theory and the number of carbon black particles per aggregate to describe their nonlinear conductive behavior. In order to consider the interactions between carbon black particles, a simple self‐consistent approach is used to improve the model. Expressions of electrical conductivity and percolation threshold are derived from the modified model. The predicted results of electrical conductivity and percolation threshold are in good agreement with experimental data reported in previous literature. Moreover, the dependences of electrical conductivity and percolation threshold on the number of carbon black particles per aggregate are discussed. Copyright © 2010 Society of Chemical Industry
Fabrication of surface‐modified CdSe quantum dots by self‐assembly of a functionalizable comb polymer
Authors: Zou Wei , Du Zhong‐jie , Li Hang‐quan , Zhang Chen
Published: April 2011

A facile approach is proposed for the fabrication of surface‐modified CdSe quantum dots (QDs) with compatibility with various media and better dispersibility by self‐assembly of a functionalizable comb polymer. The comb polymer was prepared from the reaction between the acyl chloride groups in poly(acryloyl chloride) and the hydroxyl groups in 1‐octadecanol. With the combination of the compatibility and entanglement of the aliphatic chain in 1‐octadecanol and similar aliphatic chain in oleic acid ligand of QDs, the comb polymer could cap on the QDs and thus endow them with functional groups. The structure of such a polymer was investigated using Fourier transform infrared spectroscopy. According to the reactivity of remaining acyl chloride groups in the comb polymer, the polymer ligands could be tailored to be various structures, and then lipophilic, hydrophilic and functional QDs were obtained. The fluorescence properties of the surface‐modified QDs were investigated, and the morphologies and dispersions of different kinds of surface‐modified QDs were characterized using transmission electron microscopy. Finally, homogeneous and stable dispersions of QDs in various media could be realized by adjusting the structure of the comb polymer. Copyright © 2010 Society of Chemical Industry
Evaluation of heat treatment regimes and their influences on the properties of powder‐printed high‐density polyethylene bone implant
Authors: Suwanprateeb Jintamai , Kerdsook Somrudee , Boonsiri Tanyarat , Pratumpong Patcharee
Published: April 2011

A two‐step heat treatment was utilized as a means to improve the mechanical properties of a high‐density polyethylene structure which was fabricated using the three‐dimensional printing technique. It was found that the relationship between structure and properties was strongly influenced by heat treatment conditions including treatment times (15–60 min) and treatment temperatures (140–180 °C) of both primary and secondary steps. The use of primary heating at 180 °C for 15 min and secondary heating at 160 °C for 60 min resulted in the highest tensile modulus and strength, 0.7 GPa and 14.8 MPa, respectively. The changes in both shrinkage and tensile properties were governed by the level of residual porosity and quality of polyethylene interface in samples which were both influenced by the degree of thermally induced densification and binder degradation. Empirical correlations between porosity and shrinkage or tensile properties were found to be power functions. Copyright © 2010 Society of Chemical Industry
Current management of herpes skin infections in general practice
Authors: Islam Gayti , Kudesia Goura
Published: April 2011

Herpes viruses are a common cause of viral skin infection ranging from chickenpox in children to shingles in older patients. Our Drug review discusses current management of herpes simplex and varicella‐zoster infections, followed by a review of prescription data and sources of further information. Copyright © 2011 Wiley Interface Ltd
Inverted bottom‐emission organic light emitting diodes using MoO3 for both hole and electron injections
Authors: Qin Dashan , Liu Jinsuo , Chen Yuhuan , Cheng Cuiran , Quan Wei
Published: April 2011

Inverted bottom‐emission organic light emitting diodes (IBOLEDs) using MoO3 for both hole and electron injections were fabricated. The IBOLED using 10 nm MoO3 for hole injection and 5 nm MoO3/5 nm Li2CO3 doped bathocuproine (Li2CO3:BCP, 1:4 in mass) for electron injection showed nearly same I–V characteristics as the reference device utilizing 10 nm MoO3 for hole injection and 10 nm 1:4 Li2CO3:BCP for electron injection, whereas, the former device provided increased current efficiencies than the latter device, as a result of the relieved diffusion of n‐typed dopant into the emissive layer in the former device. We provide an efficient, low‐cost alternative to realizing the electron injection in IBOLEDs.
Electronic and magneto‐optic properties of Co‐ and Ni‐doped small quantum dots of indium nitrides
Authors: Pozhar Liudmila
Published: April 2011

Structural defects in aluminium nitride (AlN) get visible in panchromatic cathodoluminescence (CL) maps as luminescence at 340 nm and 630 nm is locally enhanced. Low‐angle grain boundaries (LAGBs) and dislocations can be detected as long as they are sufficiently decorated and the defect‐related contrast is higher than local variations in background CL intensity. We applied the method to c ‐plane and a ‐plane cuts of one of our off‐oriented grown AlN crystals and describe occurrence, routes, and dissolution into dislocation bunches of LAGBs. We found that the vast majority of LAGBs are uneven a ‐planes which extend in a preferential m ‐ as well as in c ‐direction. As a consequence, their density decreases only slightly during growth (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Hole traps in n‐GaN detected by minority carrier transient spectroscopy
Authors: Tokuda Yutaka , Yamada Yujiro , Shibata Tatsunari , Yamaguchi Shintaro , Ueda Hiroyuki , Uesugi Tsutomu , Kachi Tetsu
Published: April 2011

Minority carrier transient spectroscopy (MCTS) has been applied for the detection of hole traps in n‐GaN using Schottky diodes. MCTS using 355 nm light emitting diodes is performed under isothermal conditions in the temperature range 280 to 330 K for n‐GaN grown by metalorganic chemical vapor deposition on sapphire. Isothermal MCTS spectra reveal the Ev + 0.86 eV hole trap with the trap concentration of 1.1x1016 cm‐3. The Ev + 0.86 eV hole trap has the higher concentration as compared to electron traps observed by deep level transient spectroscopy. Thus, the isothermal MCTS around room temperature provides a convenient way to evaluate the dominant trap in n‐GaN. It is suggested that the Ev + 0.86 eV hole trap is associated with the VGa‐related defect or carbon‐related defect. (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Epitaxial growth of GaN films on Cr‐compound buffer layers by plasma assisted molecular beam epitaxy
Authors: Park Jinsub , Lee Wook Hyun , Lee Seog Woo , Ha Jun‐Seok , Cho Meoung Whan , Yao Takafumi
Published: April 2011

Epitaxial GaN layers were successfully grown on Al2O3 substrate with CrN buffer layer by plasma assisted molecular beam epitaxy (PA MBE). In order to form CrN layer, two kinds of formation methods are used such as nitridation of Cr‐metal and conventional MBE growth without extra process. With reflection high energy electron diffraction pattern analysis and x‐ray diffraction (XRD) measurement, it was confirmed that formed CrN layers have a cubic structured (111) CrN with single phase at all growth temperatures. Based on photoluminescence and XRD measurements, we suggest that the procedure of CrN buffer layer formation is more preferred the conventional MBE growth to nitrided Cr metal layer for GaN growth. (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Characterization of a condensed‐phase membrane introduction mass spectrometry (CP‐MIMS) interface using a methanol acceptor phase coupled with electrospray ionization for the continuous on‐line quantitation of polar, low‐volatility analytes at trace levels in complex aqueous samples
Authors: Duncan K. D. , McCauley E. P. B. , Krogh E. T. , Gill C. G.
Published: April 2011

We report the development and application of a capillary hollow fibre membrane interface using methanol as an acceptor phase to deliver target analytes to an electrospray ionization source and a triple quadrupole mass spectrometer. Superior fluid handling systems lead to greater signal stability and membrane integrity for the continuous on‐line monitoring of polar and charged analytes in complex aqueous samples with detection limits in the parts‐per‐trillion to parts‐per‐billion range. The system can be operated in either a continuous flow or a stopped acceptor flow mode – the latter giving rise to greater sensitivity. We report detection limits, enrichment factors and signal response times for selected analytes with polydimethylsiloxane and Nafion® polymer membrane interfaces. In addition, we demonstrate the use of this interface to detect pharmaceuticals and other contaminants in natural water and artificial urine. The improved sensitivity and analytical response times of our CP‐MIMS system make it possible to continuously monitor dynamic chemical systems with temporal resolutions on the order of minutes. Presented is a comparison of the performance of CP‐MIMS versus direct infusion electrospray ionization, demonstrating the potential advantages over direct infusion for trace analyte measurements in complex, high ionic strength samples. Furthermore, by continuously flowing a reaction mixture in a closed loop over the interface, we demonstrate the use of the system as an in situ reaction‐monitoring platform for the chlorination of a model organic compound in aqueous solution. Copyright © 2011 John Wiley & Sons, Ltd.
Electron impact mass spectral study of halogenated N‐acetyl‐ and N‐propionylcytisines
Authors: Przybył Anna K. , Nowakowska Zdzisława
Published: April 2011

(−)‐Cytisine and its derivatives, characterised by high affinity to neuronal nicotinic acetylcholine receptors with specificity for the α4β2 subtype, have been shown to be important probes in central nervous system (CNS) research. Electron impact mass spectral (EI‐MS) fragmentations of halogenated derivatives of N‐acetylcytisine and N‐propionylcytisine have been investigated. Detailed fragmentation pathways have been identified for all significant ions including a few characteristic fragment ions. The principal mass spectral fragmentation routes of iodine and bromine compounds have been determined on the basis of low (EI), high resolution (HRD) and B2/E linked scan mass spectra as well as linked scans at constant B/E. Copyright © 2011 John Wiley & Sons, Ltd.
Histidine‐containing host‐defence skin peptides of anurans bind Cu2+. An electrospray ionisation mass spectrometry and computational modelling study
Authors: Wang Tianfang , Andreazza Hayley J. , Pukala Tara L. , Sherman Patrick J. , Calabrese Antonio N. , Bowie John H.
Published: April 2011

Anuran peptides which contain His, including caerin 1.8 (GLFKVLGSVAKHLLPHVVPVIAEKL‐NH2), caerin 1.2 (GLLGVLGSVAKHVLPHVVPVIAEHL‐NH2), Ala15 maculatin 1.1 (GLFGVLAKVAAHVVAIEHF‐NH2), fallaxidin 4.1 (GLLSFLPKVIGHLIHPPS‐OH), riparin 5.1 (IVSYPDDAGEHAHKMG‐NH2) and signiferin 2.1 (IIGHLIKTALGMLGL‐NH2), all form MMet2+ and (M + Met2+‐2H+)2+ cluster ions (where Met is Cu, Mg and Zn) following electrospray ionisation (ESI) in a Waters QTOF 2 mass spectrometer. Peaks due to Cu(II) complexes are always the most abundant relative to other metal complexes. Information concerning metal2+ connectivity in a complex has been obtained (at least in part) using b and y fragmentation data from ESI collision‐induced dissociation tandem mass spectrometry (CID MS/MS). Theoretical calculations, using AMBER version 10, show that MCu2+ complexes with the membrane active caerin 1.8, Ala15 maculatin 1.1 and fallaxidin 4.1 are four‐coordinate and approximating square planar, with ligands including His and Lys, together with the carbonyl oxygens of particular backbone amide groups. When binding can occur through two His, or one His and one Lys, the His/Lys ligand structure is the more stable for the studied systems. The three‐dimensional (3D) structures of the complexes are always different from the previously determined structures of the uncomplexed model peptides (using 2D nuclear magnetic resonance (NMR) spectroscopy in membrane‐mimicking solvents like trifluoroethanol/water). Copyright © 2011 John Wiley & Sons, Ltd.
Liquid chromatography/mass spectrometry of pre‐ionized Girard P derivatives for quantifying estrone and its metabolites in serum from postmenopausal women
Authors: Rangiah Kannan , Shah Sumit J. , Vachani Anil , Ciccimaro Eugene , Blair Ian A.
Published: April 2011

An ultrasensitive stable isotope dilution liquid chromatography/selected reaction monitoring/mass spectrometry (LC/SRM/MS) assay has been developed for serum estrone, 16α‐hydroxyestrone, 4‐methoxyestrone, and 2‐ methoxyestrone. The enhanced sensitivity was obtained by the use of Girard P (GP) pre‐ionized derivatives coupled with microflow LC. The limit of detection for each estrogen using 0.5 mL of serum was 0.156 pg/mL and linear standard curves were obtained up to 20 pg/mL. Serum samples from 20 postmenopausal women (10 lifetime non‐smokers and 10 current smokers) were analyzed using this new assay. Mean serum concentrations of estrone and 2‐methoxyestrone were 14.06 pg/mL (±1.56 pg/mL) and 3.30 pg/mL (±1.00 pg/mL), respectively, for the 20 subjects enrolled in the study. The mean estrone concentration determined by our ultrasensitive and highly specific assay was significantly lower than that reported for the control groups in most previous breast cancer studies of postmenopausal women. In addition (and contrary to many reports) serum 16α‐hydroxyestrone was not detected in any of the subjects, and 4‐methoxyestrone was detected in only one of the subjects. Furthermore, there were no significant differences in the mean serum concentrations of estrone and 2‐methoxyestrone or the ratio of serum 2‐ methoxyestrone to estrone between the non‐smoking and smoking groups. Interestingly, the one subject with measurable serum 4‐methoxyestrone (2.3 pg/mL) had the lowest estrone and 2‐methoxyestrone concentrations. Using this assay it will now be possible to obtain definitive information on the levels of serum estrone, 4‐methoxyestrone, and 2‐methoxyestrone in studies of cancer risk using small serum volumes available from previous epidemiology studies. Copyright © 2011 John Wiley & Sons, Ltd.
Laser ablation isotope ratio mass spectrometry for enhanced sensitivity and spatial resolution in stable isotope analysis
Authors: Moran James J. , Newburn Matt K. , Alexander M. Lizabeth , Sams Robert L. , Kelly James F. , Kreuzer Helen W.
Published: April 2011

Stable isotope analysis permits the tracking of physical, chemical, and biological reactions and source materials at a wide variety of spatial scales. We present a laser ablation isotope ratio mass spectrometry (LA‐IRMS) method that enables δ13C measurement of solid samples at 50 µm spatial resolution. The method does not require sample pre‐treatment to physically separate spatial zones. We use laser ablation of solid samples followed by quantitative combustion of the ablated particulates to convert sample carbon into CO2. Cryofocusing of the resulting CO2 coupled with modulation in the carrier flow rate permits coherent peak introduction into an isotope ratio mass spectrometer, with only 65 ng carbon required per measurement. We conclusively demonstrate that the measured CO2 is produced by combustion of laser‐ablated aerosols from the sample surface.

We measured δ13C for a series of solid compounds using laser ablation and traditional solid sample analysis techniques. Both techniques produced consistent isotopic results but the laser ablation method required over two orders of magnitude less sample. We demonstrated that LA‐IRMS sensitivity coupled with its 50 µm spatial resolution could be used to measure δ13C values along a length of hair, making multiple sample measurements over distances corresponding to a single day's growth.

This method will be highly valuable in cases where the δ13C analysis of small samples over prescribed spatial distances is required. Suitable applications include forensic analysis of hair samples, investigations of tightly woven microbial systems, and cases of surface analysis where there is a sharp delineation between different components of a sample. Copyright © 2011 John Wiley & Sons, Ltd.
Accurate mass and nuclear magnetic resonance identification of bisphenolic can coating migrants and their interference with liquid chromatography/tandem mass spectrometric analysis of bisphenol A
Authors: Ackerman Luke K. , Noonan Gregory O. , Begley Timothy H. , Mazzola Eugene P.
Published: April 2011

Two unknown compounds were previously determined to be potential interferences in liquid chromatography/tandem mass spectrometry (LC/MS/MS) analysis of bisphenol A (BPA) in canned infant formula. Both yielded two identical MS/MS transitions to BPA. The identities of the unknowns were investigated using accurate mass LC/MS, LC/MS/MS, and elemental formula and structures proposed. Exact identities were confirmed through purification or synthesis followed by 1H and 13C nuclear magnetic resonance (NMR) experiments, as well as comparisons of one unknown with commercial standards. Comparisons of negative ion electrospray ionization (ESI) MS/MS and accurate mass spectra suggested both unknowns to be structurally identical (to BPA and each other). Positive ion ESI spectra confirmed both were larger molecules, suggesting that in the negative mode they likely fragmented to the BPA molecular ion in the source. Elemental composition of positive ion accurate mass spectra and NMR analysis concluded the unknowns were oxidized forms of the known epoxy can coating monomer, bisphenol A diglycidyl ether (BADGE). One of the unknowns, 2,2‐[bis‐4‐(2,3‐dihydroxypropoxy)phenyl]propane, commonly known as BADGE*2H2O, is widely reported as an epoxy‐phenolic can coating migrant, but has not been suggested to interfere with the MS/MS analysis of BPA. The other unknown, 2‐[4‐(2,3‐dihydroxypropoxy)phenyl]‐2‐[4'‐hydroxyphenyl]propane, or the oxidized form of bisphenol A monoglycidyl ether (BAMGE*H2O), has not been previously reported in food or packaging. Published in 2011 by John Wiley & Sons, Ltd.
Multi‐equilibrium property of metabolic networks: Exclusion of multi‐stability for SSN metabolic modules
Authors: Lei Hong‐Bo , Zhang Ji‐Feng , Chen Luonan
Published: April 2011

It is a fundamental and important problem whether or not a metabolic network can admit multiple equilibria in a living organism. Due to the complexity of the metabolic network, it is generally a difficult task to study the problem as a whole from both analytical and numerical viewpoints. In this paper, a structure‐oriented modularization research framework is proposed to analyze the multi‐stability of metabolic networks. We first decompose a metabolic network into four types of basic building blocks (called metabolic modules) according to the particularity of its structure, and then focus on one type of these basic building blocks—the single substrate and single product with no inhibition (SSN) module, by deriving a nonlinear ordinary differential equation (ODE) model based on the Hill kinetics. We show that the injectivity of the vector field of the ODE model is equivalent to the nonsingularity of its Jacobian matrix, which enables us equivalently to convert an unverifiable sufficient condition for the absence of multiple equilibria of an SSN module into a verifiable one. Moreover, we prove that this sufficient condition holds for the SSN module in a living organism. Such a theoretical result not only provides a general framework for modeling metabolic networks, but also shows that the SSN module in a living organism cannot be multi‐stable. Copyright © 2011 John Wiley & Sons, Ltd.
A likelihood‐based comparison of temporal models for physical processes
Authors: Braverman Amy , Cressie Noel , Teixeira Joao
Published: April 2011

Many scientific and engineering problems involve physical modeling of complex processes. Sometimes multiple candidate models are available, and their performance can be compared by how well their outputs match observations. Various summary statistics can be used for this purpose, but no matter which statistics are chosen, it is important that comparisons based on them be considered in light of the inherent variability of the data used in their calculation. In this article, we consider the variability of a summary statistic through an empirical likelihood. The approach is nonparametric in the sense that a moving‐block bootstrap procedure is used to obtain the empirical likelihood. Relative figures of merit for each candidate model are formed as the ratio of each candidate model's likelihood to the largest likelihood. We use a small simulation study to show that our procedure can correctly distinguish between different time series models, and then we demonstrate how the method can be used to evaluate the output of 20 Intergovernmental Panel on Climate Change (IPCC) atmospheric models based on their agreement with the observations. © 2011 California Institute of Technology. Government sponsorship acknowledged. Statistical Analysis and Data Mining 2011
Organic Molecules Reconstruct Nanostructures on Ionic Surfaces
Authors: Trevethan Thomas , Such Bartosz , Glatzel Thilo , Kawai Shigeki , Shluger Alexander L. , Meyer Ernst , de Mendoza Paula , Echavarren Antonio M.
Published: April 2011

Modification and functionalization of the atomic‐scale structure of insulating surfaces is fundamental to catalysis, self‐assembly, and single‐molecule technologies. Specially designed syn‐5,10,15‐tris(4‐cyanophenylmethyl)truxene molecules can reshape features on an ionic KBr (001) surface. Atomic force microscopy images demonstrate that both KBr monolayer islands and pits can reshape from rectangular to round structures, a process which is directly facilitated by molecular adsorption. Simulations reveal that the mechanism of the surface reconstruction consists of collective atomic hops of ions on the step edges of the islands and pits, which correlate with molecular motion. The energy barriers for individual processes are reduced by the presence of the adsorbed molecules, which cause surface structural changes. These results show how appropriately designed organic molecules can modify surface morphology on insulating surfaces. Such strongly adsorbed molecules can also serve as anchoring sites for building new nanostructures on inert insulating surfaces.
Introducing agile customer‐centered development in a legacy software product line
Authors: Bosch Jan , Bosch‐Sijtsema Petra M.
Published: April 2011

The ability to rapidly respond to customer interest and to effectively prioritize development effort has been a long‐standing challenge for mass‐market software intensive products. This problem is exacerbated in the context of software product lines as functionality may easily fall over software asset and organizational boundaries with consequent losses in efficiency and nimbleness. Some companies facing these problems in their product line respond with a new development process. In this paper we discuss the developments within a single case study, Intuit's Quickbooks product line that combined agile software development, design thinking and self‐organizing teams in a successful approach, which provided a significant improvement in terms of responsiveness and accuracy of building customer value. Copyright © 2011 John Wiley & Sons, Ltd.
Second‐trimester soft markers: relation to first‐trimester nuchal translucency in unaffected pregnancies
Authors: Miguelez J. , De Lourdes Brizot M. , Liao A. W. , De Carvalho M. H. B. , Zugaib M.
Published: April 2011

Objective

Genetic sonography following first‐trimester combined screening appears to increase substantially detection rates for Down syndrome but it relies on the unproved assumption of independence between these tests. In this study we aimed to investigate the relationship between first‐trimester nuchal translucency (NT) and a series of second‐trimester soft markers and structural defects in unaffected pregnancies.

Methods

NT measurement in the first trimester was followed by second‐trimester scan (18 to 23 + 6 weeks) including examination for three categorical markers (intracardiac echogenic foci, hyperechogenic bowel and structural defects) and measurement of nasal bone length, nuchal‐fold thickness, femur length, humerus length, renal pelvis diameter and prenasal thickness. All continuous variables were expressed in multiples of the median (MoM) for gestation and correlation coefficients between log‐transformed NT and second‐trimester variables were calculated. In addition, frequencies of soft markers and structural defects in cases with increased NT were compared to those with normal NT, using MoM cut‐offs.

Results

In a dataset of 1970 cases, NT was significantly correlated (P < 0.05) with all second‐trimester continuous variables, the correlation being strongest for nuchal‐fold thickness (r = 0.10). There was a higher frequency of cases with second‐trimester nuchal‐fold thickness above the 97.5th centile (10.7 vs. 2.2%) and hyperechogenic bowel (2.4 vs. 0.1%) in cases with increased NT.

Conclusions

Straightforward reassessment of risk using likelihood ratios derived from the second‐trimester genetic sonogram might lead to inaccurate estimates. Multivariate models using continuous second‐trimester variables might be preferable in sequential screening strategies. Copyright © 2012 ISUOG. Published by John Wiley & Sons, Ltd.
Climate change and spaceflight: an historiographical review
Authors: Launius Roger D.
Published: April 2011

This article discusses the broad use of space‐based resources to study climate change and the historical efforts to understand this effort. The historiography of this subject is still in its infancy, but there are several benchmark studies that focus on NASA's efforts along these lines. The key work of Erik Conway, Mark Bowen, and other recent researchers inform this study. This article concludes with a discussion of possibilities for future historical studies in climate change and spaceflight. WIREs Clim Change 2011 2 412–427 DOI: 10.1002/wcc.114

This article is categorized under:

Climate, History, Society, Culture > Technological Aspects and Ideas
Organic‐inorganic Hybrid Lanthanide‐Silver Heterometallic Coordination Frameworks Constructed from Oxalate and Sulfate Anion: Syntheses, Structures, and Photoluminescent Properties
Authors: Xiao Xueying , Wei Yongqin , Zheng Wenxu , Wu Kechen
Published: April 2011

The first four examples of organic‐inorganic hybrid lanthanide‐silver heterometallic frameworks, namely, [AgLn(μ5‐C2O4)(SO4)(H2O)2] [Ln = Eu (1) and Sm (2)] and [AgLn(μ4‐C2O4)0.5(μ6‐C2O4)0.5(SO4)(H2O)] [Ln = Tb (3) and Dy (4)] based on oxalate and sulfate anions were synthesized by hydrothermal reactions of lanthanide oxide, silver nitrate, oxalic acid and sulfuric acid. All structures contain ladder‐like inorganic lanthanide sulfato chains, which are further connected together through silver atoms by oxalate anions with different coordination behavior (μ5‐C2O4: 1 and 2, μ6‐C2O4 mixed μ4‐C2O4: 3 and 4) to generate two types of 3D networks. The luminescent properties of these compounds were also studied.
On the Existence of LiFeVO4 – Tales and Imagination
Authors: Clemens Oliver , Bauer Matthias , Haberkorn Robert , Beck Horst Philipp
Published: April 2011

In this paper, we report investigations on the synthesis of LiFeVO4 as well as a reinvestigation of recently published research reports. Starting with compounds containing V4+ and Fe3+ for synthesis showed to be the best way to realize the desired composition. A single phase material could not be prepared, instead, we find a disproportionation of V4+ to V3+ and V5+ and separation of these ions into two different phases, such as Li0.5+Fe(5z–1)/2z3+V0.5z3+O4 and Li(1–0.5z)/(1–z)+Fe(1.5–2.5z)/(1–z)3+V0.5/(1–z)5+O4, with z ≈︁ 0.45. Additionally, XANES / EXAFS measurements were performed to determine the cation oxidation states and coordination.
Defect in proline synthesis: pyrroline‐5‐carboxylate reductase 1 deficiency leads to a complex clinical phenotype with collagen and elastin abnormalities
Authors: Kretz Rita , Bozorgmehr Bita , Kariminejad Mohamad Hasan , Rohrbach Marianne , Hausser Ingrid , Baumer Alessandra , Baumgartner Matthias , Giunta Cecilia , Kariminejad Ariana , Häberle Johannes
Published: April 2011

Pyrroline‐5‐carboxylate reductase 1 (PYCR1) catalyzes the last step in proline synthesis. Deficiency of PYCR1, caused by a defect in PYCR1, was recently described in patients with cutis laxa, intrauterine growth retardation, developmental dysplasia of the hips and mental retardation. In this paper, we describe additional six patients (ages ranging from 4 months to 55 years) from four Iranian families with clinical manifestations of a wrinkly skin disorder. All patients have distinct facial features comprising triangular face, loss of adipose tissue and thin pointed nose. Additional features are short stature, wrinkling over dorsum of hand and feet, visible veins over the chest and hyperextensible joints. Three of the patients from a large consanguineous family do not have mental retardation, while the remaining three patients from three unrelated families have mental and developmental delay. Mutation analysis revealed the presence of disease‐causing variants in PYCR1, including a novel deletion of the entire PYCR1 gene in one family, and in each of the other patients the homozygous missense mutations c.616G > A (p.Gly206Arg), c.89T > A (p.Ile30Lys) and c.572G > A (p.Gly191Glu) respectively, the latter two of which are novel. Light‐ and electron microscopy investigations of skin biopsies showed smaller and fragmented elastic fibres, abnormal morphology of the mitochondria and their cristae, and slightly abnormal collagen fibril diameters with irregular outline and variable size. In conclusion, this study adds information on the natural course of PYCR1 deficiency and sheds light on the pathophysiology of this disorder. However, the exact pathogenesis of this new disorder and the role of proline in the development of the clinical phenotype remain to be fully explained.
Catalytic Synthesis of Fatty Acid Methyl Esters from Extremely Low Quality Greases
Authors: Ngo Helen L. , Xie Zhigang , Kasprzyk Stephen , Haas Michael , Lin Wenbin
Published: April 2011

Biodiesel (BD) is a renewable fuel for compression ignition engines that is composed of the simple alkyl esters, usually methyl‐, of fatty acids (FAME). It is typically produced via base‐catalyzed transesterification between refined vegetable oil or animal fat (e.g., soybean oil, tallow) and an alcohol (e.g., methanol). This process can, however, be marginally cost‐effective due to the high feedstock and processing costs. It is thus desirable to develop new catalytic routes that can efficiently convert less expensive feedstocks to BD. We report here on the application of a series of diarylammonium based homogeneous and heterogeneous catalysts for converting a particularly low value, low quality lipid, trap grease, to FAME. In the course of a 1‐h reaction at 125 °C these catalysts simultaneously esterified the free fatty acids (>90 wt% of the substrate) and transesterified the acylglycerols (<10 wt%) of the feedstock to FAME with greater than 95% overall conversion.
The uniform Korn–Poincaré inequality in thin domains
Authors: Lewicka Marta , Müller Stefan
Published: April 2011

We study the Korn–Poincaré inequality:

\|u\|_{W^{1,2}(S^{h})}\leq C_{h}\left\|D(u)\right\|_{L^{2}(S^{h})},

in domains

S^{h}

that are shells of small thickness of order

h

, around an arbitrary compact, boundaryless and smooth hypersurface

S

in

\mathbf{R}^{n}

. By

D(u)

we denote the symmetric part of the gradient

∇u

, and we assume the tangential boundary conditions:

u \cdot \overrightarrow n^{h} = 0\:\text{on }\partial S^{h}.

We prove that

C_{h}

remains uniformly bounded as

h\rightarrow 0

, for vector fields

u

in any family of cones (with

\text{angle} < \pi / 2

, uniform in

h

) around the orthogonal complement of extensions of Killing vector fields on

S

.

We show that this condition is optimal, as in turn every Killing field admits a family of extensions

u^{h}

, for which the ratio

\|u^{h}\|_{W^{1,2}(S^{h})}/ \|D(u^{h})\|_{L^{2}(S^{h})}

blows up as

h\rightarrow 0

, even if the domains

S^{h}

are not rotationally symmetric.

On étudie lʼinégalité de Korn–Poincaré :

\|u\|_{W^{1,2}(S^{h})}\leq C_{h}\left\|D(u)\right\|_{L^{2}(S^{h})},

dans les domaines

S^{h}

de type des coques dʼépaisseurs dʼordre

h

autour dʼune hypersurface compacte sans bord et regulière

S

de

\mathbf{R}^{n}

. Par

D(u)

, on réfère à la partie symétrique du gradient

∇u

et on suppose la condition au bord :

u \cdot \overrightarrow n^{h} = 0\:\text{on }\partial S^{h}.

On démontre que

C_{h}

reste uniformément borné car

h\rightarrow 0

, pour tout champ de vecteurs dans une famille de cônes donnée (faisant un

\text{angle} < \pi / 2

, uniforme en

h

) autour du complément orthogonal des extensions de champs de vecteurs de Killing sur

S

.

On montre que cette condition est optimale comme tout champ de Killling

u

sur

S

admet une famille dʼextensions

u^{h}

sur

S^{h}

pour lesquelles le rapport

\|u^{h}\|_{W^{1,2}(S^{h})}/ \|D(u^{h})\|_{L^{2}(S^{h})}

tend à lʼinfini comme

h\rightarrow 0

, même si les

S^{h}

ne possèdent pas de symmetrie axiale.