bluuebunny/crossref_metadata_2025 huggingface dataset:
Water‐Soluble Tetraphenylethene Derivatives as Fluorescent “Light‐Up” Probes for Nucleic Acid Detection and Their Applications in Cell Imaging
Authors: Hong Yuning , Chen Sijie , Leung Chris Wai Tung , Lam Jacky Wing Yip , Tang Ben Zhong
Published: April 2013

The detection of nucleic acids, such as DNA and RNA, plays a significant role in genetic engineering, forensics, and bioinformatics. Traditional nucleic acid probes are mainly intercalators, which are potential mutagens, or groove binders that show high preference only for double‐stranded DNA. We herein present two versatile fluorescent probes for nucleic acid detection and visualization. The nonemissive tetraphenylethene derivatives (TTAPE) are induced by DNA/RNA to emit, thereby showing a novel phenomenon of aggregation‐induced emission (AIE). This kind of “light‐up” property enables the quantitation and visualization of nucleic acids in aqueous solution and electrophoretic gels, respectively. The cationic TTAPE can penetrate cells with a compromised plasma membrane easily but cannot enter live cells with an intact membrane, thus making them useful for the differentiation between dead and live cells. On account of the high binding affinity to DNA, TTAPE can selectively label the chromosomes and nuclei in fixed cells, which provides a simple and fast method for the observation of cell mitosis. Owing to their AIE characteristics, the dye molecules aggregate in DNA‐rich regions and exert appreciable quantum efficiency as well as superior photostability.
[Fe]‐Hydrogenase and Models that Contain IronAcyl Ligation
Authors: Schultz Katherine M. , Chen Dafa , Hu Xile
Published: April 2013

[Fe]‐hydrogenase is a newly characterized type of hydrogenase. This enzyme heterolytically splits hydrogen in the presence of a natural substrate. The active site of the enzyme contains a mono‐iron complex with intriguing ironacyl ligation. Several groups have recently developed ironacyl complexes as synthetic models of [Fe]‐hydrogenase. This Focus Review summarizes the studies of this enzyme and its model compounds, with an emphasis on our own research in this area.
Total Synthesis of an Immunomodulatory Phosphoglycolipid from Thermophilic Bacteria
Authors: Lin Hong‐Jyune , Adak Avijit Kumar , Reddy L. Vijaya Raghava , Wu Shih‐Hsiung , Lin Chun‐Cheng
Published: April 2013

A method for the stereocontrolled synthesis of a bacterial phosphoglycolipid (PGL1) isolated from thermophilic bacteria is described. The key features of the synthesis include a highly α‐selective glycosylation reaction between a trichloroacetimidate donor and a D‐lyxose‐derived primary alcohol acceptor and the late‐stage incorporation of the phospholipid.
A Sensitive and Selective Fluorescent Probe for Cysteine Based on a New Response‐Assisted Electrostatic Attraction Strategy: The Role of Spatial Charge Configuration
Authors: Zhou Xin , Jin Xuejun , Sun Guangyan , Wu Xue
Published: April 2013

A new strategy for fast fluorescent detection of cysteine (Cys), based on a response‐assisted electrostatic attraction, is demonstrated. By utilizing this strategy, we designed and synthesized three fluorescent probes for the specific detection of Cys under actual physiological conditions. The probe m‐CP, a coumarin fluorophore conjugated with a substituted methyl pyridinium group through an unsaturated ketone unit, showed highly selective and sensitive detection for cysteine (Cys) over homocysteine (Hcy) and glutathione (GSH). The kinetic analysis indicated that the sensing process was highly accelerated (a response time less than 1 min) by the response‐assisted electrostatic attraction. More importantly, control experiments with isomeric probes first demonstrated that the spatial charge configuration of the probe played an important role in Cys‐preferred selectivity and kinetic rate acceleration. Furthermore, the practical utility of the probe m‐CP in the fluorescent labeling of Cys residues within proteins was demonstrated. Finally, these probes were employed in living cell imaging with HeLa cells, in which it displayed satisfactory cell permeability and enabled us to distinguish active thiols in the cytoplasm, nucleus, and mitochondria.
Expression of Neurogenin 1 in Mouse Embryonic Stem Cells Directs the Differentiation of Neuronal Precursors and Identifies Unique Patterns of Down‐stream Gene Expression
Authors: Velkey J. Matthew , O'Shea K. Sue
Published: April 2013

COVER PHOTOGRAPH: Neuronal differentiation of tet‐inducible Neurogenin1‐expressing ES cells 3 days after transgene induction, stained with antibodies recognizing Sox3 (green) and neuron‐specific class III b‐tubulin (amber); nuclei stained with Hoechst 33258 (blue). From Expression of Neurogenin 1 in Mouse Embryonic Stem Cells Directs the Differentiation of Neuronal Precursors and Identifies Unique Patterns of Down‐stream Gene Expression, Matthew Velkey and Sue O'Shea, Developmental Dynamics 242:230–253, 2013.
Expression pattern of Nogo‐A, MAG, and NgR in regenerating urodele spinal cord
Authors: Hui Subhra Prakash , Monaghan James R. , Voss S. Randal , Ghosh Sukla
Published: April 2013

Background: The mammalian central nervous system is incapable of substantial axon regeneration after injury partially due to the presence of myelin‐associated inhibitory molecules including Nogo‐A and myelin associated glycoprotein (MAG). In contrast, axolotl salamanders are capable of considerable axon regrowth during spinal cord regeneration. Results: Here, we show that Nogo‐A and MAG, and their receptor, Nogo receptor (NgR), are present in the axolotl genome and are broadly expressed in the central nervous system (CNS) during development, adulthood, and importantly, during regeneration. Furthermore, we show that Nogo‐A and NgR are co‐expressed in Sox2 positive neural progenitor cells. Conclusions: These expression patterns suggest myelin‐associated proteins are permissive for neural development and regeneration in axolotls. Developmental Dynamics 242:847–860, 2013. © 2013 Wiley Periodicals, Inc.
Probabilistic diagnosis of short‐circuit faults and insulation deterioration of stator winding of motor
Authors: Nakamura Hisahide , Mizuno Yukio
Published: April 2013

Short‐circuit faults of winding due to deterioration of the insulation are one of the most probable faults in motor drive systems. An easy and eﬀective method for fault diagnosis is very much needed to assure operation with high reliability. This paper proposes a novel method for diagnosing both short‐circuit faults and insulation deterioration in windings. This method involves an impulse voltage test and probabilistic process for gauging the probability of fault occurrence by analyzing the distributions of features depending on the condition of the winding. In this paper, ﬁrst, we discuss the results of several impulse tests on the winding. Second, two features that represent the characteristics corresponding to the condition of the winding are induced, and their feature distributions are determined. Third, we introduce the probability that can be used to diagnose conditions of the winding. The average and standard deviation of both features are calculated. By using the calculated values and features observed in a target winding to be examined, the fault probability is computed. Finally, the usefulness of the proposed diagnosis method is veriﬁed by experiments involving the use of faulty and deteriorating windings. © 2013 Wiley Periodicals, Inc. Electr Eng Jpn, 184(1): 30–41, 2013; Published online in Wiley Online Library (wileyonlinelibrary.com). DOI 10.1002/eej.22399
Multinuclear NMR Spectroscopic and X‐ray Crystallographic Studies of Electronic and Steric Effects of Phosphonous Acid Ligands and Their Chlorophosphite Ligand Precursors in Tungsten Pentacarb­onyl Complexes
Authors: Hastings Samantha D. , Byrd Houston , Gray Leanne N. , Jablonsky Michael J. , Freeman Jason L. , Gray Gary M.
Published: April 2013

Although phosphonous acid ligands have recently become of interest for use in transition metal complex catalysts for organic reactions such as alkene hydroformylations, the factors that affect the steric and electronic properties of these ligands have not been studied in detail. To gain insight into the electronic and steric properties of phosphonous acid ligands, we have prepared tungsten(0) pentacarbonyl complexes with chlorophosphite ligands derived from either 2,2′‐biphenol or (±)‐1,1′‐bi‐2‐naphthol and have then hydrolyzed the coordinated ligands to generate tungsten(0) pentacarbonyl complexes with the corresponding phosphonous acid ligands. NMR measurements of the W–P coupling constants demonstrate that changing the biaryl groups from biphenyl to binaphthyl does not affect the electron‐donor ability of the ligand, whereas changing the third substituent from chloro to oxo has a significant effect. Estimation of cone angles of the ligands from X‐ray crystallographic data have shown that neither changing the biaryl group nor changing the third substituent have a significant effect on their cone angles. Further, these studies have identified important intra‐ and intermolecular interactions that favor certain ligand conformations. The data could be useful for the development of catalytic structure–activity relationships that could be used in the rational design of catalysts.
How to Perform More Effective Audits by Focusing on the Data
Authors: Singleton Tommie
Published: April 2013

Because more and more accounting systems are automated, data have become the key to auditing those systems. The fact is, the figures in financial reports are data being printed in the appropriate format. When a transaction is initiated, data are created. When anything happens to that transaction, data are changed or moved or posted. And when it comes time to print the financial reports, data are extracted from the accounting database and assembled for printing. Therefore, data are centric to the system and the financial reports. And if data are centric to the accounting system and financial reports, then it is a logical conclusion that they should be centric to audits. The author discusses how to perform more effective audits by focusing on the data. © 2013 Wiley Periodicals, Inc.
Process optimization for catalytic glycolysis of post‐consumer PET wastes
Authors: Duque‐Ingunza I. , López‐Fonseca R. , de Rivas B. , Gutiérrez‐Ortiz J. I.
Published: April 2013

Background

Glycolysis has been the subject of increased interest as a valuable feedstock recycling for poly(ethylene terephthalate) (PET). However, there are no reports in the technical literature that deal with the design and optimization of the global process.

Results

Conversion into bis(2‐hydroxyethyl) terephthalate (BHET) of the non‐glycolyzed solid was feasible, carried out in the presence or absence of fresh PET. The yield varied between 63 and 80%. The monomer was recovered by extraction with hot water followed by crystallization at 4 °C. The optimized H2O:BHET ratio was 6.7 mL g‐1. The EG(ethylene glycol)/H2O mixture was effectively separated by vacuum distillation and EG of 99.6% purity was recovered, which could be used again. Finally, the highly active catalytic role of sodium carbonate salt for glycolysis was evident not only for transparent PET wastes but also for complex wastes.

Conclusions

The recirculation of the solid residue from extraction, the separation of EG/H2O mixture from crystallization and the subsequent refeeding of the organic reactant into the reactor, the minimization of the amount of water to efficiently recover the monomer and the suitability of the chemical recycling of complex PET wastes are operational aspects that significantly increased the global efficiency. © 2013 Society of Chemical Industry
3D T2‐weighted spin echo imaging in the breast
Authors: Moran Catherine J. , Hargreaves Brian A. , Saranathan Manojkumar , Lipson Jafi A. , Kao Jennifer , Ikeda Debra M. , Daniel Bruce L.
Published: April 2013

Purpose

To evaluate the performance of 2D versus 3D T2‐weighted spin echo imaging in the breast.

Materials and Methods

2D and 3D T2‐weighted images were acquired in 25 patients as part of a clinically indicated breast magnetic resonance imaging (MRI) exam. Lesion‐to‐fibroglandular tissue signal ratio was measured in 16 identified lesions. Clarity of lesion morphology was assessed through a blinded review by three radiologists. Instances demonstrating the potential diagnostic contribution of 3D versus 2D T2‐weighted imaging in the breast were noted through unblinded review by a fourth radiologist.

Results

The lesion‐to‐fibroglandular tissue signal ratio was well correlated between 2D and 3D T2‐weighted images (R2 = 0.93). Clarity of lesion morphology was significantly better with 3D T2‐weighted imaging for all observers based on a McNemar test (P ≤ 0.02, P ≤ 0.01, P ≤ 0.03). Instances indicating the potential diagnostic contribution of 3D T2‐weighted imaging included improved depiction of signal intensity and improved alignment between DCE and T2‐weighted findings.

Conclusion

In this pilot study, 3D T2‐weighted imaging provided comparable contrast and improved depiction of lesion morphology in the breast in comparison to 2D T2‐weighted imaging. Based on these results further investigation to determine the diagnostic impact of 3D T2‐weighted imaging in breast MRI is warranted. J. Magn. Reson. Imaging 2014;39:332–338. © 2013 Wiley Periodicals, Inc.
Effect of flip angle on the accuracy and repeatability of hepatic proton density fat fraction estimation by complex data‐based, T1‐independent, T2*‐corrected, spectrum‐modeled MRI
Authors: Johnson Benjamin L. , Schroeder Michael E. , Wolfson Tanya , Gamst Anthony C. , Hamilton Gavin , Shiehmorteza Masoud , Loomba Rohit , Schwimmer Jeffrey B. , Reeder Scott , Middleton Michael S. , Sirlin Claude B.
Published: April 2013

Purpose

To evaluate the effect of flip angle (FA) on accuracy and within‐examination repeatability of hepatic proton‐density fat fraction (PDFF) estimation with complex data‐based magnetic resonance imaging (MRI).

Materials and Methods

PDFF was estimated at 3T in 30 subjects using two sets of five MRI sequences with FA from 1° to 5° in each set. One set used 7 msec repetition time and acquired 6 echoes (TR7/E6); the other used 14 msec and acquired 12 echoes (TR14/E12). For each FA in both sets the accuracy of MRI‐PDFF was assessed relative to MR spectroscopy (MRS)‐PDFF using four regression parameters (slope, intercept, average bias, R2). Each subject had four random sequences repeated; within‐examination repeatability of MRI‐PDFF for each FA was assessed with intraclass correlation coefficient (ICC). Pairwise comparisons were made using bootstrap‐based tests.

Results

Most FAs provided high MRI‐PDFF estimation accuracy (intercept range −1.25 to 0.84, slope 0.89–1.06, average bias 0.24–1.65, R2 0.85–0.97). Most comparisons of regression parameters between FAs were not significant. Informally, in the TR7/E6 set, FAs of 2° and 3° provided the highest accuracy, while FAs of 1° and 5° provided the lowest. In the TR14/E12 set, accuracy parameters did not differ consistently between FAs. FAs in both sets provided high within‐examination repeatability (ICC range 0.981–0.998).

Conclusion

MRI‐PDFF was repeatable and, for most FAs, accurate in both sequence sets. In the TR7/E6 sequence set, FAs of 2° and 3° informally provided the highest accuracy. In the TR14/E12 sequence set, all FAs provided similar accuracy. J. Magn. Reson. Imaging 2014;39:440–447. © 2013 Wiley Periodicals, Inc.
A single amino acid substitution in viral VP1 protein alters the lytic potential of clone‐derived variants of echovirus 9 DM strain in human pancreatic islets
Authors: Paananen A. , Ylipaasto P. , Smura T. , Lempinen M. , Galama J. , Roivainen M.
Published: April 2013

In vitro studies with primary human pancreatic islets suggest that several enterovirus serotypes are able to infect and replicate in beta cells. Some enterovirus strains are highly cytolytic in vitro whereas others show virus replication with no apparent islet destruction. The capability to induce islet destruction is determined only partially by the virus serotype, since strain specific differences have been detected within some serotypes including echovirus 9 (E‐9). In this study, the viral genetic factors determining the outcome of islet infection (i.e., destructive vs. benign) were investigated by constructing parallel infectious clones of lytic E‐9‐DM strain that was isolated from a small child at the clinical onset of type 1 diabetes. The capabilities of these clone‐derived viruses to induce islet destruction were monitored and the lytic potential of clones was modified by site‐directed mutagenesis. The lytic capabilities of these clone‐derived viruses in human pancreatic islets were modified by a single amino acid substitution (T81A) in the capsid protein VP1. The data presented outline the importance of amino acid point mutations in the pathogenetic process leading to islet necrosis. However, although the amino acid substitution (T81A) modifies the lytic capabilities of E‐9‐DM strain‐derived microvariant strains, it is likely that additional viral genetic determinants of pancreatic islet pathogenicity exist in other E‐9 strains. J. Med. Virol. 85:1267–1273, 2013. © 2013 Wiley Periodicals, Inc.
Nanoprecipitation of PMMA Stabilized by Core Cross‐Linked Star Polymers
Authors: Miao Miao , Chen Qijing , Zhang Chunlei , Cao Xueteng , Zhou Wei , Qiu Qian , An Zesheng
Published: April 2013

Nanoprecipitation of poly(methyl methacrylate) (PMMA) in the presence of water‐soluble core cross‐linked star (CCS) polymers is investigated. Slowly dropping water into DMF solutions containing PMMA and CCS polymers of varying compositions produces colloidally stable particles with CCS polymers being effectively incorporated. During the solvent‐shifting process, CCS polymers migrate to and concentrate at the particle surface to stabilize the formed particles, which is confirmed by X‐ray photoelectron spectroscopy, transmission electron microscopy, and contact angle measurements. This stabilizing effect is realized via the steric effect of the CCS polymers adsorbed at the particle surface.

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Small carbon‐carbon couplings in monosubstituted benzenes – their signs and magnitudes determined by HCSE method
Authors: Blechta Vratislav , Schraml Jan
Published: April 2013

Signed values of all intra‐ring 2,3,4J(C,C) couplings in nine monosubstituted benzenes (C6H5‐X where X = F, Cl, Br, CH3, OCH3, Si(CH3)3, C ≡ N, NO, NO2) are experimentally determined as well as nine couplings to substituent carbons. It is confirmed that while all the vicinal intra‐ring 3J(C,C) are positive and all geminal 2J(C2,C4) are negative, both signs are found for geminal 2J(C1,C3) couplings. All the determined signs agree with those already predicted by theoretical calculations. Copyright © 2013 John Wiley & Sons, Ltd.
A three‐phase thermo‐hydro‐mechanical finite element model for freezing soils
Authors: Zhou M.M. , Meschke G.
Published: April 2013

Artificial ground freezing (AGF) is a commonly used technique in geotechnical engineering for ground improvement such as ground water control and temporary excavation support during tunnel construction in soft soils. The main potential problem connected with this technique is that it may produce heave and settlement at the ground surface, which may cause damage to the surface infrastructure. Additionally, the freezing process and the energy needed to obtain a stable frozen ground may be significantly influenced by seepage flow. Evidently, safe design and execution of AGF require a reliable prediction of the coupled thermo‐hydro‐mechanical behavior of freezing soils. With the theory of poromechanics, a three‐phase finite element soil model is proposed, considering solid particles, liquid water, and crystal ice as separate phases and mixture temperature, liquid pressure, and solid displacement as the primary field variables. In addition to the volume expansion of water transforming into ice, the contribution of the micro‐cryo‐suction mechanism to the frost heave phenomenon is described in the model using the theory of premelting dynamics. Through fundamental physical laws and corresponding state relations, the model captures various couplings among the phase transition, the liquid transport within the pore space, and the accompanying mechanical deformation. The verification and validation of the model are accomplished by means of selected analyses. An application example is related to AGF during tunnel excavation, investigating the influence of seepage flow on the freezing process and the time required to establish a closed supporting frozen arch. Copyright © 2013 John Wiley & Sons, Ltd.
A comparative study of short‐ and long‐TE 1H MRS at 3 T for in vivo detection of 2‐hydroxyglutarate in brain tumors
Authors: Choi Changho , Ganji Sandeep , Hulsey Keith , Madan Akshay , Kovacs Zoltan , Dimitrov Ivan , Zhang Song , Pichumani Kumar , Mendelsohn Dianne , Mickey Bruce , Malloy Craig , Bachoo Robert , DeBerardinis Ralph , Maher Elizabeth
Published: April 2013

2‐Hydroxyglutarate (2HG) is produced in gliomas with mutations of isocitrate dehydrogenase (IDH) 1 and 2. The 1H resonances of the J‐coupled spins of 2HG are extensively overlapped with signals from other metabolites. Here, we report a comparative study at 3 T of the utility of the point‐resolved spectroscopy sequence with a standard short TE (35 ms) and a long TE (97 ms), which had been theoretically designed for the detection of the 2HG 2.25‐ppm resonance. The performance of the methods is evaluated using data from phantoms, seven healthy volunteers and 22 subjects with IDH‐mutated gliomas. The results indicate that TE = 97 ms provides higher detectability of 2HG than TE = 35 ms, and that this improved capability is gained when data are analyzed with basis spectra that include the effects of the volume localizing radiofrequency and gradient pulses. Copyright © 2013 John Wiley & Sons, Ltd.
Visceral fat resection in humans: Effect on insulin sensitivity, beta‐cell function, adipokines, and inflammatory markers
Authors: Lima Marcelo M. O. , Pareja Jose C. , Alegre Sarah M. , Geloneze Sylka R. , Kahn Steven E. , Astiarraga Brenno D. , Chaim Élinton A. , Baracat Jamal , Geloneze Bruno
Published: April 2013

Objective: The visceral fat is linked to insulin resistance, the metabolic syndrome, type 2 diabetes and an increased cardiovascular risk, but it is not clear whether it has a causative role.

Design and Methods: Surgical resection of this fat depot is a research model to address this issue. Twenty premenopausal women with metabolic syndrome and grade III obesity were randomized to undergo Roux‐en‐Y gastric bypass (RYGBP) either alone or combined with omentectomy. Insulin sensitivity (IS; euglycemic‐hyperinsulinemic clamp), acute insulin response to glucose (AIR; intravenous glucose tolerance test), disposition index (DI = AIR × IS measured by clamp), lipid profile, adipokine profile (leptin, adiponectin, resistin, visfatin, interleukin‐6, TNF‐α, MCP‐1), ultra‐sensitive C‐reactive protein (CRP), body composition, and abdominal fat echography were assessed prior to surgery and 1, 6, and 12 months post‐surgery.

Results: Omentectomy was associated with greater weight loss at all time points. IS improved similarly in both groups. Omentectomy was associated to lower CRP after 12 months, but it did not influence adipokines and other metabolic parameters. Among non‐diabetic subjects, omentectomy was associated with a preservation of baseline AIR after 12 months (as opposed to deterioration in the control group) and a greater DI after 6 and 12 months.

Conclusion: Although omentectomy did not enhance the effect of RYGBP on insulin sensitivity and adipokines, it was associated with a preservation of insulin secretion, a greater weight loss, and lower CRP.
A dairy‐based high calcium diet improves glucose homeostasis and reduces steatosis in the context of preexisting obesity
Authors: Thomas Anthony P. , Dunn Tamara N. , Drayton Josephine B. , Oort Pieter J. , Adams Sean H.
Published: April 2013

Objective:

High dietary calcium (Ca) in the context of a dairy food matrix has been shown to reduce obesity development and associated inflammation in diet‐induced obese (DIO) rodents. The influence of Ca and dairy on these phenotypes in the context of preexisting obesity is not known. Furthermore, interpretations have been confounded historically by differences in body weight gain among DIO animals fed dairy‐based protein or high Ca.

Design and Methods:

Adiposity along with associated metabolic and inflammatory outcomes were measured in DIO mice previously fattened for 12 week on a soy protein‐based obesogenic high fat diet (45% energy, 0.5% adequate Ca), then fed one of three high fat diets (n = 29‐30/group) for an additional 8 week: control (same as lead‐in diet), high‐Ca (1.5% Ca), or high‐Ca + nonfat dry milk (NFDM).

Results and Conclusion:

Mice fed high‐Ca + NFDM had modestly, but significantly, attenuated weight gain compared to mice fed high‐Ca or versus controls (P < 0.001), whereas mice fed high‐Ca alone had increased weight gain compared to controls (P < 0.001). Total measured adipose depot weights between groups were similar, as were white adipose tissue inflammation and macrophage infiltration markers (e.g. TNFα, IL‐6, CD68 mRNAs). Mice fed high‐Ca + NFDM had significantly improved glucose tolerance following a glucose tolerance test, and markedly lower liver triglycerides compared to high‐Ca and control groups. Improved metabolic phenotypes in prefattened DIO mice following provision of a diet enriched with dairy‐based protein and carbohydrates appeared to be driven by non‐Ca components of dairy and were observed despite minimal differences in body weight or adiposity.
Six‐minute walk test before and after a weight reduction program in obese subjects
Authors: Ekman Maja J. , Klintenberg M. , Björck U. , Norström F. , Ridderstråle M.
Published: April 2013

Obejctive: Weight loss and physical activity have shown favorable effects on risks associated with obesity. It is therefore of interest to evaluate exercise capacity and related co‐morbidities in obese patients.

Design and Methods: We present data from obese subjects evaluated by the 6‐minute walk test (6MWT) before and after a 7.3 (6.1‐8.2) month weight reduction program.

Results: 251 subjects completed the test at baseline (BMI 40.6 [36.9‐44.6] kg/m2) and 129 (51.4%) repeated the test after intervention (BMI 35.6 [31.2‐38.5] kg/m2). The six minute walking distance (6MWD) at baseline (535 [480‐580] m) and at follow up (599 [522‐640] m) correlated to several cardiovascular risk markers. Age, weight, height, resting heart rate, smoking status, fP‐glucose and use of β‐blockers explained 43 % of the variance in predicted 6MWD at baseline. The effect of smoking status, fP‐glucose, β‐blockers, and resting heart rate lost significance at follow up. Presence of diabetes and the metabolic syndrome had a negative influence on 6MWD but did not affect the impact of intervention based on percentage increase in walking distance. Gender had no impact on 6MWD. Reported pain during the test was common but decreased after intervention (57.0% vs. 28.7%, P < 0.001).

Conclusions:The 6MWT may be used to evaluate intervention success beyond kilogram weight loss in obese subjects. We present formulas to predict 6MWD and the effect of weight loss on walking distance in clinical practice. Pain is a common problem which has to be considered when giving advice on exercise as a part of weight loss intervention.
Endothelial function and weight loss: Comparison of low‐carbohydrate and low‐fat diets
Authors: Mohler Emile R. , Sibley Alexandra A. , Stein Richard , Davila‐Roman Victor , Wyatt Holly , Badellino Karen , Rader Daniel J. , Klein Samuel , Foster Gary D.
Published: April 2013

Objective: The effect of weight loss on obesity‐associated endothelial dysfunction is not clear because of conflicting data, demonstrating both improvement and no change in endothelial function after weight loss in obese subjects. A 2‐year prospective study (n = 121) was conducted to examine: (1) the effect of obesity and weight loss (either a low‐carbohydrate or and low‐fat diet) on flow mediated vasodilatation (FMD), a measure of endothelial function.

Design and Methods: Participants reduced body weight by 7.1% ± 4.4%, 8.7% ± 6.8%, 7.1% ± 7.8%, and 4.1% ± 7.7% at 3, 6, 12, and 24 months, respectively with no significant differences between the low‐fat and low‐carbohydrate groups.

Results: Endothelial function was inversely correlated with waist circumference, triglyceride level, and directly correlated with leptin in obese persons prior to weight loss. These weight losses did not confer any improvements in FMD. There were no differences between the low‐fat and low‐carbohydrate diets in FMD at any time point. At 6 months (r = 0.26, P = 0.04) and 1 year (r =0.28, P = 0.03), there were positive correlations between change in FMD and change in leptin but not at 2 years.

Conclusion: There was no significant improvement in endothelial function after 7.1% ± 7.8% weight loss at 1 year and 4.1% ± 7.7% at 2 years, achieved by either a low carbohydrate or a low fat diet.
Gastric Helicobacter pylori infection is associated with adverse metabolic traits in severely obese subjects
Authors: Gerig Rahel , Ernst Barbara , Wilms Britta , Thurnheer Martin , Schultes Bernd
Published: April 2013

Objective:

Asian studies have reported on an association of Helicobacter pylori (Hp) infection with insulin resistance (IR) in normal‐weight subjects. Whether such an association likewise exists in European subjects with severe obesity was questioned.

Design and Methods:

To address this question, 370 severely obese patients from our database were identified, who had undergone a gastroscopy with a histological examination of gastric mucosal biopsies and a concurrent assessment metabolic blood parameters as a standard examination before bariatric surgery.

Results:

Seventy‐five (20.3%) of the subjects displayed a histologically proven Hp infection (Hp+). Sex distribution, age, and body mass index of Hp+ subjects did not differ from that of the subjects with no Hp infection (Hp–; all P > 0.293), but Hp+ subjects were significantly smaller (P = 0.006). Fasting glucose, insulin, high‐sensitive C reactive protein, and alanine aminotransferase levels as well as calculated indices of IR (i.e., HOMA‐IR, QUICKI) did not differ between Hp+ and Hp– subjects (all P > 0.42). However, Hp+ subjects showed significantly higher triglyceride levels and a higher total chloesterol‐to‐HDL ratio but lower sex‐hormone binding globulin (SHGB) levels than Hp– subjects (all P ≤ 0.05).

Conclusion:

While our results obtained in European severely obese patients do not provide evidence for an enhanced IR state associated with gastric Hp infection, they suggest that the presence of the bacterium in gastric biopsies is associated with an adverse lipid profile and reduced SHGB levels.
Meta‐analysis of the association between body mass index and health‐related quality of life among adults, assessed by the SF‐36
Authors: Ul‐Haq Zia , Mackay Daniel F. , Fenwick Elisabeth , Pell Jill P.
Published: April 2013

Objective:

Obesity is associated with impaired overall health‐related quality of life but individual studies suggest the relationship may differ for mental and physical quality of life. A systematic review using Medline, Embase, PsycINFO and ISI Web of Knowledge, and random effects meta‐analysis was undertaken.

Design and Methods:

Studies were included in the meta‐analysis if they were conducted on adults (defined as age >16 years), reported an overall physical and mental component score of the SF‐36, and, or both. Heterogeneity was assessed using I2 statistics and publication and small study biases using funnel plots and Egger's test. Between‐study heterogeneity was explored using meta‐regression.

Results:

Eight eligible studies provided 42 estimates of effect size, based on 43,086 study participants. Adults with higher than normal body mass index had significantly reduced physical quality of life with a clear dose‐response relationship across all categories. Among class III obese adults, the score was reduced by 9.72 points (95% Confidence Interval 7.24, 12.20, P < 0.001). Mental quality of life was also significantly reduced among class III obese (−1.75, 95% confidence interval −3.33, −0.16, P = 0.031), but was not significantly different among obese (class I and class II) individuals, and was significantly increased among overweight adults (0.42, 95% confidence interval 0.17, 0.67, P = 0.001), compared to normal weight individuals. Heterogeneity was high in some categories, but there was no significant publication or small study bias.

Conclusions:

Different patterns were observed for physical and mental HRQoL, but both were impaired in obese individuals. This meta‐analysis provides further evidence on the impact of obesity on both aspects of health‐related quality of life.
Epicardial adipose tissue assessed by cardiac magnetic resonance imaging in patients with heart failure due to dilated cardiomyopathy
Authors: Doesch Christina , Streitner Florian , Bellm Steven , Suselbeck Tim , Haghi Dariusch , Heggemann Felix , Schoenberg Stefan O. , Michaely Henrik , Borggrefe Martin , Papavassiliu Theano
Published: April 2013

Objective:

We sought to investigate the association of the EAT with CMR parameters of ventricular remodelling and left ventricular (LV) dysfunction in patients with non‐ischemic dilated cardiomyopathy (DCM).

Design and Methods:

One hundred and fifty subjects (112 consecutive patients with DCM and 48 healthy controls) underwent CMR examination. Function, volumes, dimensions, the LV remodelling index (LVRI), the presence of late gadolinium enhancement (LGE) and the amount of EAT were assessed.

Results:

Compared to healthy controls, patients with DCM revealed a significantly reduced indexed EAT mass (31.7 ± 5.6 g/m2 vs 24.0 ± 7.5 g/m2, p<0.0001). There was no difference in the EAT mass between DCM patients with moderate and severe LV dysfunction (23.5 ± 9.8 g/m2 vs 24.2 ± 6.6 g/m2, P = 0.7). Linear regression analysis in DCM patients showed that with increasing LV end‐diastolic mass index (LV‐EDMI) (r = 0.417, P < 0.0001), increasing LV end‐diastolic volume index (r = 0.251, P = 0.01) and increasing LV end‐diastolic diameter (r = 0.220, P = 0.02), there was also a significantly increased amount of EAT mass. However, there was no correlation between the EAT and the LV ejection fraction (r = 0.0085, P = 0.37), right ventricular ejection fraction (r = 0.049, P = 0.6), LVRI (r = 0.116, P = 0.2) and the extent of LGE % (r = 0.189, P = 0.1). Among the healthy controls, the amount of EAT only correlated with increasing age (r = 0.461, P = 0.001), BMI (r = 0.426, P = 0.003) and LV‐EDMI (r = 0.346, P = 0.02).

Conclusion:

In patients with DCM the amount of EAT is decreased compared to healthy controls irrespective of LV function impairment. However, an increase in LV mass and volumes is associated with a significantly increase in EAT in patients with DCM.
Placental weight mediates the effects of prenatal factors on fetal growth: the extent differs by preterm status
Authors: Ouyang Fengxiu , Parker Margaret , Cerda Sandra , Pearson Colleen , Fu Lingling , Gillman Matthew W. , Zuckerman Barry , Wang Xiaobin
Published: April 2013

Objective:

Elevated pre‐pregnancy BMI, excessive gestational weight gain (GWG), and gestational diabetes mellitus (GDM) are known determinants of fetal growth. The role of placental weight is unclear. We aimed to examine the extent to which placental weight mediates the associations of pre‐pregnancy BMI, GWG, and GDM with birth weight‐for‐gestational age, and whether the relationships differ by preterm status.

Design and Methods:

We examined 1,035 mother‐infant pairs at birth from the Boston Birth Cohort. Data were collected by questionnaire and clinical measures. Placentas were weighed without membranes or umbilical cords. We performed sequential models excluding and including placental weight, stratified by preterm status.

Results:

We found that 21% of mothers were obese, 42% had excessive GWG, and 5% had GDM. Forty‐one percent were preterm. Among term births, after adjustment for sex, gestational age, maternal age, race, parity, education, smoking, and stress during pregnancy, birth weight‐for‐gestational age z‐score was 0.55 (0.30, 0.80) units higher for pre‐pregnancy obesity vs. normal weight. It was 0.34 (0.13, 0.55) higher for excessive vs. adequate GWG, 0.67 (0.24, 1.10) for GDM vs. no DM, with additional adjustment for pre‐pregnancy BMI. Adding placental weight to the models attenuated the estimates for pre‐pregnancy obesity by 20%, excessive GWG by 32%, and GDM by 21%. Among preterm infants, GDM was associated with 0.67 (0.34, 1.00) higher birth weight‐for‐gestational age z‐score, but pre‐pregnancy obesity and excessive GWG were not. Attenuation by placental weight was 36% for GDM.

Conclusions:

These results suggest that placental weight partially mediates the effects of pre‐pregnancy obesity, GDM, and excessive GWG on fetal growth among term infants.
Diet composition and activity level of at risk and metabolically healthy obese american adults
Authors: Hankinson Arlene L. , Daviglus Martha L. , Horn Linda Van , Chan Queenie , Brown Ian , Holmes Elaine , Elliott Paul , Stamler Jeremiah
Published: April 2013

Objective:

Obesity often clusters with other major cardiovascular disease risk factors, yet a subset of the obese appears to be protected from these risks. Two obesity phenotypes are described, (i) “metabolically healthy” obese, broadly defined as body mass index (BMI) ≥ 30 kg/m2 and favorable levels of blood pressure, lipids, and glucose; and (ii) “at risk” obese, BMI ≥ 30 with unfavorable levels of these risk factors. More than 30% of obese American adults are metabolically healthy. Diet and activity determinants of obesity phenotypes are unclear. We hypothesized that metabolically healthy obese have more favorable behavioral factors, including less adverse diet composition and higher activity levels than at risk obese in the multi‐ethnic group of 775 obese American adults ages 40‐59 years from the International Population Study on Macro/Micronutrients and Blood Pressure (INTERMAP) cohort.

Design and Methods:

In gender‐stratified analyses, mean values for diet composition and activity behavior variables, adjusted for age, race, and education, were compared between metabolically healthy and at risk obese.

Results:

Nearly one in five (149/775 or 19%) of obese American INTERMAP participants were classified as metabolically healthy obese. Diet composition and most activity behaviors were similar between obesity phenotypes, although metabolically healthy obese women reported higher sleep duration than at risk obese women.

Conclusions:

These results do not support hypotheses that diet composition and/or physical activity account for the absence of cardiometabolic abnormalities in metabolically healthy obese.
A Novel Approach in Herbal Quality Control Using Hyperspectral Imaging: Discriminating Between Sceletium tortuosum and Sceletium crassicaule
Authors: Shikanga Emmanuel Amukohe , Viljoen Alvaro M. , Vermaak Ilze , Combrinck Sandra
Published: April 2013

Introduction

Sceletium tortuosum is the most sought after species of the genus Sceletium and is commonly included in commercial products for the treatment of psychiatric conditions and neurodegenerative diseases. However, this species exhibits several morphological and phytochemical similarities to S. crassicaule.

Objectives

The aim of this investigation was to use ultrahigh‐performance liquid chromatography (UPLC) and hyperspectral imaging, in combination with chemometrics, to distinguish between S. tortuosum and S. crassicaule, and to accurately predict the identity of specimens of both species.

Methods

Chromatographic profiles of S. tortuosum and S. crassicaule specimens were obtained using UPLC with photodiode array detection. A SisuChema near infrared hyperspectral imaging camera was used for acquiring images of the specimens and the data was processed using chemometric computations.

Results

Chromatographic data for the specimens revealed that both species produce the psychoactive alkaloids that are used as quality control biomarkers. Principal component analysis of the hyperspectral image of reference specimens for the two species yielded two distinct clusters, the one representing S. tortuosum and the other representing S. crassicaule. A partial least squares discriminant analysis model correctly predicted the identity of an external dataset consisting of S. tortuosum or S. crassicaule samples with high accuracy (>94%).

Conclusions

A combination of hyperspectral imaging and chemometrics offers several advantages over conventional chromatographic profiling when used to distinguish S. tortuosum from S. crassicaule. In addition, the constructed chemometric model can reliably predict the identity of samples of both species from an external dataset. Copyright © 2013 John Wiley & Sons, Ltd.
Noninvasive twin zygosity assessment and aneuploidy detection by maternal plasma DNA sequencing
Authors: Leung Tak Y. , Qu James Z. Z. , Liao Gary J. W. , Jiang Peiyong , Cheng Yvonne K. Y. , Chan K. C. Allen , Chiu Rossa W. K. , Lo Y. M. Dennis
Published: April 2013

Objective

This study aimed to provide an individualized assessment of fetal trisomy 21 and trisomy 18 status for twin pregnancies by maternal plasma DNA sequencing.

Method

Massively parallel sequencing was performed on the plasma/serum DNA libraries of eight twin pregnancies and 11 singleton pregnancies. The apparent fractional fetal DNA concentrations between genomic regions were assessed to determine the zygosities of the twin pregnancies and to calculate the fetal DNA concentrations of each individual member of dizygotic twin pairs. Z‐scores were determined for the detection of trisomy 18 and trisomy 21.

Results

Circulating DNA sequencing showed elevated chromosome 21 representation in one set of twins and elevated chromosome 18 representation in another pair of twins. Apparent fractional fetal DNA concentration analysis revealed both sets of twins to be dizygotic. The fractional fetal DNA concentrations for each individual fetus of the dizygotic twin pregnancies were determined. Incorporating the information about the fetal DNA fraction, we ascertained that each fetus contributed adequate amounts of DNA into the maternal circulation for the aneuploidy test result to be interpreted with confidence.

Conclusion

Noninvasive prenatal assessment of fetal chromosomal aneuploidy for twin pregnancies can be achieved with the use of massively parallel sequencing of cell‐free DNA in maternal blood. © 2013 John Wiley & Sons, Ltd.
Synthesis and phase behaviors of side‐chain liquid‐crystalline polymers containing azobenzene mesogen with the different length alkyl tail
Authors: Chen Sheng , Ling Aihua , Zhang Hai‐Liang
Published: April 2013

A series of side‐chain liquid‐crystal polymers, poly[6‐[4‐(4′‐n‐alkyl benzoateazo)phenoxy]‐hexylmethacrylate]s (PMAzoCOORm, m = 1, 2, 3, 4, 5, 6, 8, 10, 14, and 18) have been prepared by two synthetic methods. The chemical structure of the monomers was confirmed by 1H NMR and mass spectrometry. The molecular characterizations of the polymers were performed with 1H NMR and gel permeation chromatograph. The phase behaviors of polymers were investigated by the combination of techniques including differential scanning calorimetry, polarized optical microscopy, and small‐angle X‐ray scattering. For m = 1, 2, 3, 4, 5, and 6, the polymers exhibited a monosmectic A phase in which the smectic layer period was almost identical to the side‐chain length. In addition, for m = 2, 3, 4, and 5, they presented the monosmectic C phase in low temperature; moreover, the tilt angle increased from 23.3 to 40.5°. For m = 8, 10, 14, and 18, the polymers showed a bilayer smectic A phase in which the layer spacing was larger than a fully extended side chain but less than two extended chains. On the other hand, for the clearing point, with the increasing of m, it first decreased, and then increased. All of these indicated that the length of alkyl tails played an important role in the phase behaviors of these polymers. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2013, 51, 2759–2768
Structural analyses of the pre‐mRNA splicing machinery
Authors: Zhang Lingdi , Li Xueni , Zhao Rui
Published: April 2013

Pre‐mRNA splicing is a critical event in the gene expression pathway of all eukaryotes. The splicing reaction is catalyzed by the spliceosome, a huge protein‐RNA complex that contains five snRNAs and hundreds of different protein factors. Understanding the structure of this large molecular machinery is critical for understanding its function. Although the highly dynamic nature of the spliceosome, in both composition and conformation, posed daunting challenges to structural studies, there has been significant recent progress on structural analyses of the splicing machinery, using electron microscopy, crystallography, and nuclear magnetic resonance. This review discusses key recent findings in the structural analyses of the spliceosome and its components and how these findings advance our understanding of the function of the splicing machinery.
Doubly Labelled Water analysis: Preparation, memory correction, calibration and quality assurance for δ2H and δ18O measurements over four orders of magnitudes
Authors: Guidotti S. , Jansen H. G. , Aerts‐Bijma A. T. , Verstappen‐Dumoulin B. M. A. A. , van Dijk G. , Meijer H. A. J.
Published: April 2013

RATIONALE

The Doubly Labelled Water (DLW) method is an established way of determining the metabolic rate in humans and animals, with the advantage that the subjects need not be confined. The method, however, needs accurate determination of both the δ2H and the δ18O isotope values over a wide range of enrichments.

METHODS

In this paper we describe a number of crucial steps in the process of isotope determination in body fluids. These steps include micro‐distillation, correction of the measurements for sample‐to‐sample memory and calibration of the isotope scales over many orders of magnitudes. In contrast to several published protocols and guidelines, we also take highly enriched samples into account, as they are required for studying the metabolic rate of birds and small mammals. For our isotope scale calibration, we made a set of gravimetrically prepared, double labelled waters with known isotope values. Our quality assurance includes a scheme for easy calculation of the error propagation, leading to a reliable estimate of the analytical error in the metabolic rate.

RESULTS

Our memory correction algorithm assumes the existence of three water “pools” that have different sizes and exchange rates with the injected samples. We show that the method can correct even huge memory signals, without the need for “true” values.

CONCLUSIONS

With the presented building blocks, we show how to assure a reliable and accurate isotope analysis for the DLW method, both for human and for animal applications. Although our measurements have been performed using isotope ratio mass spectrometry, most of the procedures are also useful for laser spectrometry. Copyright © 2013 John Wiley & Sons, Ltd.
Corporate Social Responsibility: An Uneasy Merger of Sustainability and Development
Authors: Luke Timothy W.
Published: April 2013

This study reevaluates the origins and operations of corporate social responsibility (CSR) programs since the 1980s and 1990s in the USA. Such enterprises mobilize sustainable development rhetoric as part of stylized political agendas for community outreach, social impact, cultural sensitivity and environmental justice campaigns endorsed by big business. These campaigns react to political pressures exerted by local, national or global anti‐corporate movements, and sustainable development has become one moderately successful negotiated settlement in this battle between the private sector and civil society. Nonetheless, a brittle quality in weak interpretations of sustainable development remains engrained in many CSR programs as standard operating procedures. These profit‐driven agendas push for ‘development' over ‘sustainability’, lowering the bar for what sustainability should, or does, mean for businesses as they struggle to be more responsible ethical actors in society. Copyright © 2013 John Wiley & Sons, Ltd and ERP Environment.