bluuebunny/crossref_metadata_2025 huggingface dataset:
Body mass index change in gastrointestinal cancer and chronic obstructive pulmonary disease is associated with Dedicator of Cytokinesis 1
Authors: McDonald Merry‐Lynn Noelle , Won Sungho , Mattheisen Manuel , Castaldi Peter J. , Cho Michael H. , Rutten Erica , Hardin Megan , Yip Wai‐Ki , Rennard Stephen I. , Lomas David A. , Wouters Emiel F.M. , Agusti Alvar , Casaburi Richard , Lange Christoph P. , O'Connor George , Hersh Craig P. , Silverman Edwin K.
Published: January 2017

Background

There have been a number of candidate gene association studies of cancer cachexia‐related traits, but no genome‐wide association study (GWAS) has been published to date. Cachexia presents in patients with a number of complex traits, including both cancer and COPD. The objective of the current investigation was to search for a shared genetic aetiology for change in body mass index (ΔBMI) among cancer and COPD by using GWAS data in the Framingham Heart Study.

Methods

A linear mixed effects model accounting for age, sex, and change in smoking status was used to calculate ΔBMI in participants over 40 years of age with three consecutive BMI time points (n = 4162). Four GWAS of ΔBMI using generalized estimating equations were performed among 1085 participants with a cancer diagnosis, 204 with gastrointestinal (GI) cancer, 112 with lung cancer, and 237 with COPD to test for association with 418 365 single‐nucleotide polymorphisms (SNPs).

Results

Two SNPs reached a level of genome‐wide significance (P < 5 × 10−8) with ΔBMI: (i) rs41526344 within the CNTN4 gene, among COPD cases (β = 0.13, P = 4.3 × 10−8); and (ii) rs4751240 in the gene Dedicator of Cytokinesis 1 (DOCK1) among GI cancer cases (β = 0.10, P = 1.9 × 10−8). The DOCK1 SNP association replicated in the ΔBMI GWAS among COPD cases (βmeta‐analyis = 0.10, Pmeta‐analyis = 9.3 × 10−10). The DOCK1 gene codes for the dedicator of cytokinesis 1 protein, which has a role in myoblast fusion.

Conclusions

In sum, one statistically significant common variant in the DOCK1 gene was associated with ΔBMI in GI cancer and COPD cases providing support for at least partially shared aetiology of ΔBMI in complex diseases.
Male greater sage‐grouse movements among leks
Authors: Fremgen Aleshia L. , Rota Christopher T. , Hansen Christopher P. , Rumble Mark A. , Gamo R. Scott , Millspaugh Joshua J.
Published: January 2017

Movements among leks by breeding birds (i.e., interlek movements) could affect the population's genetic flow, complicate use of lek counts as a population index, and indicate a change in breeding behavior following a disturbance. We used a Bayesian multi‐state mark‐recapture model to assess the daily probability of male greater sage‐grouse (Centrocercus urophasianus) interlek movements and estimate factors influencing movements among leks. We fitted 145 males with solar Argos global positioning systems platform transmitter terminals over 4 years (2011–2014) in Carbon County, Wyoming, USA. The daily probability of a male sage‐grouse moving among leks ranged 0.003 (95% CI = 0.000–0.010) in 2011 to 0.010 (95% CI = 0.001–0.021) in 2013, indicating high daily lek fidelity throughout the season, although there was a 5–42% chance annually a male would move at least once to another lek throughout the season ( days analyzed/M = 55 ± 3.3 days [SE]). Interlek movement probabilities were strongly affected by day of year, peaking early in the lek season. Interlek movements were positively associated with elevation. Seasonal interlek movements occurred more frequently than previously reported, and can bias lek counts in early spring as males move from low to high elevation leks, which reinforces interlek movements as a critical component of lek ecology. © 2016 The Wildlife Society.
Creating impact resonance through a culture of Holistic Discoverability
Authors: Sommer David
Published: January 2017

Key points

Discoverability is no longer just about technology.

There is a shift towards a culture of discovery.

Coordinated efforts successfully create impact resonance.

The author is the conductor of impact.

Today, everybody needs to take responsibility for creating impact.
Where and how early career researchers find scholarly information
Authors: Nicholas David , Boukacem‐Zeghmouri Cherifa , Rodríguez‐Bravo Blanca , Xu Jie , Watkinson Anthony , Abrizah A. , Herman Eti , Świgoń Marzena
Published: January 2017

This article presents findings from the first year of the Harbingers research project started in 2015. The project is a 3‐year longitudinal study of early career researchers (ECRs) to ascertain their current and changing habits with regard to information searching, use, sharing, and publication. The study recruited 116 researchers from seven countries (UK, USA, China, France, Malaysia, Poland, and Spain) and performed in‐depth interviews by telephone, Skype, or face‐to‐face to discover behaviours and opinions. This paper reports on findings regarding discovery and access to scholarly information. Findings confirm the universal popularity of Google/Google Scholar. Library platforms and web‐scale discovery services are largely unmentioned and unnoticed by this user community, although many ECRs pass through them unknowingly on the way to authenticated use of their other preferred sources, such as Web of Science. ECRs are conscious of the benefits of open access in delivering free access to papers. Social media are widely used as a source of discovering scholarly information. ResearchGate is popular and on the rise in all countries surveyed. Smartphones have become a regularly used platform on which to perform quick and occasional searches for scholarly information but are only rarely used for reading full text.
Long‐Term Stable Poly(acrylamide) Brush Modified Transparent Microwells for Cell Attachment Studies in 3D
Authors: Lilge Inga , Jiang Siyu , Schönherr Holger
Published: January 2017

The fabrication of 3D cell microenvironments exploiting versatile, long‐term stable passivating poly(acryl amide) brushes in a microwell format and the study of the behavior of fibroblast and pancreatic tumor cells in wells of systematically varied shape and size is reported. The microwells, which are obtained by combining micromolding in capillaries with microcontact printing of initiator monolayers for subsequent surface‐initiated polymerization of acrylamide and controlled functionalization with fibronectin (FN), expose cell adhesive areas inside the wells and protein and cell resistant brushes on the topside plateaus. NIH 3T3 fibroblast and pancreatic tumor (Patu 8988T) cells adhere and remain viable in the FN coated microwells for more than 1 week. Compared to 2D patterns, both cell lines are observed to attach to the bottom as well as the sidewalls of the microwells. The cytoskeleton alignment is found to be less pronounced compared to 2D patterned substrates, independent of microwell size and geometry.

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A note on a generalization of the Schwarz theorem about the equality of mixed partial derivatives
Authors: Delladio Silvano
Published: January 2017

We provide a generalization of the classical Schwarz theorem about the equality of mixed partial derivatives. More precisely we extend it to a Riemannian manifold , by proving the following statement: if is a couple of commuting vector fields on M and are such that the set is superdense at a certain point , then .
3D Printing of Aniline Tetramer‐Grafted‐Polyethylenimine and Pluronic F127 Composites for Electroactive Scaffolds
Authors: Dong Shi‐Lei , Han Lu , Du Cai‐Xia , Wang Xiao‐Yu , Li Lu‐Hai , Wei Yen
Published: January 2017

Electroactive hydrogel scaffolds are fabricated by the 3D‐printing technique using composites of 30% Pluronic F127 and aniline tetramer‐grafted‐polyethylenimine (AT‐PEI) copolymers with various contents from 2.5% to 10%. The synthesized AT‐PEI copolymers can self‐assemble into nanoparticles with the diameter of ≈50 nm and display excellent electroactivity due to AT conjugation. The copolymers are then homogeneously distributed into 30% Pluronic F127 solution by virtue of the thermosensitivity of F127, denoted as F/AT‐PEI composites. Macroscopic photographs of latticed scaffolds elucidate their excellent printability of F/AT‐PEI hydrogels for the 3D‐printing technique. The conductivities of the printed F/AT‐PEI scaffolds are all higher than 2.0 × 10−3 S cm−1, which are significantly improved compared with that of F127 scaffold with only 0.94 × 10−3 S cm−1. Thus, the F/AT‐PEI scaffolds can be considered as candidates for application in electrical stimulation of tissue regeneration such as repair of muscle and cardiac nerve tissue.

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Efficient and Regioselectivity‐Tunable Metal‐Free Polycycloaddition of Activated Azide and Alkynes
Authors: Wu Yongwei , He Benzhao , Wang Jia , Hu Rongrong , Zhao Zujin , Huang Fei , Qin Anjun , Tang Ben Zhong
Published: January 2017

The transition‐metal catalyzed and metal‐free click polymerizations have been developed as powerful tools for the construction of functional polymers with linear and hyperbranched structures. The latter provides a thorough solution for the completely removing metallic residues from the products encountered in the former. Compared to the activated alkyne–azide metal‐free click polymerization, the activated azide–alkyne one is rarely studied. In this Communication, a perfluorophenyl‐activated azide of hexane‐1,6‐diyl‐bis(4‐azido‐2,3,5,6‐tetrafluorobenzoate) is rationally designed and facilely prepared. Through systematical optimization of the reaction conditions, an efficient metal‐free perfluorophenylazide–alkyne polycycloaddition is established, and polytriazoles with high molecular weights (up to 166 000) and excellent solubility are obtained in excellent yields (up to 93%) under mild reaction conditions. Interestingly, the regioselectivity of the reaction could be fine‐tuned by the solvents and diyne monomers. Therefore, this work provides not only a powerful tool for the preparation of functional polytriazoles, but also an attractive method for fine‐tuning their regioregularity.

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A Multiresponsive Amphiphilic Supramolecular Diblock Copolymer Based on Pillar[10]arene/Paraquat Complexation for Rate‐Tunable Controlled Release
Authors: Chi Xiaodong , Ji Xiaofan , Shao Li , Huang Feihe
Published: January 2017

Herein, for rate‐tunable controlled release, the authors report a new facile method to prepare multiresponsive amphiphilic supramolecular diblock copolymers via the cooperative complexation between a water‐soluble pillar[10]arene and paraquat‐containing polymers in water. This supramolecular diblock copolymer can self‐assemble into multiresponsive polymeric micelles at room temperature in water. The resultant micelles can be further used in the controlled release of small molecules with tunable release rates depending on the type of single stimulus and the combination of various stimuli.

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No Strain, No Gain? Enzymatic Ring‐Opening Polymerization of Strainless Aliphatic Macrolactones
Authors: Witt Timo , Häußler Manuel , Mecking Stefan
Published: January 2017

Starting from readily available oleic and erucic acid, macrocyclic nonadecalactone (C19) and tricosalactone (C23) can be synthesized in polymerization grade purity in a four‐step reaction sequence. Ring‐opening polymerization (ROP) of these strainless macrolactones can be performed utilizing an enzyme as a catalyst. Despite the missing ring‐strain as key driving force for smaller (strained) lactones, high molar masses (Mn ≈ 105 g mol−1) can be accessed in an entropically driven ROP. Polyester‐19 and polyester‐23 prepared feature melting temperatures well above 100 °C. Further analysis of the mechanical properties of these materials displays the resemblance to polyethylene. For example, Young's moduli on the order of 600 MPa are observed as a result of the high crystallinity of the polymer.

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Cyclic Multiblock Copolymers via Combination of Iterative Cu(0)‐Mediated Radical Polymerization and Cu(I)‐Catalyzed Azide‐Alkyne Cycloaddition Reaction
Authors: Xiao Lifen , Zhu Wen , Chen Jiqiang , Zhang Ke
Published: January 2017

Cyclic multiblock polymers with high‐order blocks are synthesized via the combination of single‐electron transfer living radical polymerization (SET‐LRP) and copper‐catalyzed azide‐alkyne cycloaddition (CuAAC). The linear α,ω‐telechelic multiblock copolymer is prepared via SET‐LRP by sequential addition of different monomers. The SET‐LRP approach allows well control of the block length and sequence as A‐B‐C‐D‐E, etc. The CuAAC is then performed to intramolecularly couple the azide and alkyne end groups of the linear copolymer and produce the corresponding cyclic copolymer. The block sequence and the cyclic topology of the resultant cyclic copolymer are confirmed by the characterization of 1H nuclear magnetic resonance spectroscopy, gel permeation chromatography, Fourier transform infrared spectroscopy, and matrix‐assisted laser desorption/ionization time‐of‐flight mass spectrometry.

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Heterogeneities in Polymer Structural and Dynamic Properties in Graphene and Graphene Oxide Nanocomposites: Molecular Dynamics Simulations
Authors: Azimi Majid , Mirjavadi Seyed Sajad , Hamouda Abdel Magid Salem , Makki Hesam
Published: January 2017

The effect of graphene (G) and graphene oxide (GO), used as the nanofiller in polymer nanocomposites (NC), on the structural and dynamic properties of polymer chains, has been studied by means of molecular dynamics (MD) simulations. Two polymers, i.e., poly(propylene) and poly(vinyl alcohol), are employed as matrices to cover a wider range of polymer–filler interactions. The local structural properties, e.g., density profile, average Rg, and end‐to‐end distance as well as dynamic properties, e.g., estimated translational and orientational relaxation times, of polymer chains are studied. In addition, the interaction energies are estimated between polymers and nanofillers for different hybrid systems using MD pullout simulations. Strong heterogeneities in polymer structural and dynamic properties have been observed such that chains are more oriented and exhibit slower dynamics in the vicinity of the nanofillers (G and GO) as compared to bulk. It is also found that the orientation of polymer chains at the interface is more influenced by the nanofiller in such a way that the more oriented polymer chains are observed in G‐based NC for both polymers. However, the immobilization of polymer chains at the interface proves to be very much dependent on the polymer–filler interactions.

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Supermicrosurgical lymphaticovenous anastomosis for a patient with breast lymphedema secondary to breast cancer treatment
Authors: Giacalone Guido , Yamamoto Takumi
Published: January 2017

Breast lymphedema (BLE) has been reported as a complication following breast cancer treatment. As for extremity lymphedema treatment, supermicrosurgical lymphaticovenous anastomosis (LVA) is considered an option for the treatment of progressive BLE refractory to conservative treatments, but no case has been reported so far. We report the first case of BLE successfully treated with supermicrosurgical LVA. A 55‐year‐old female presented with left BLE after breast conserving surgery and axillary lymph node dissection and adjuvant radiotherapy. After the cancer treatments, the patient suffered from pronounced swelling, sensation of tension, and pain of the left breast with frequent episodes of breast cellulitis. Conservative treatments had been performed for 7 years, but were not effective, and the patient was referred for further surgical treatment. Supermicrosurgical LVA was performed at the left breast. LVA surgery resulted in three anastomoses, in which three lymphatic vessels were anastomosed to three nearby veins in an intima‐to‐intima coaptation manner. After LVA, the left breast decreased in size, and the sensation of tension disappeared. One year postoperatively, the patient had no distress nor cellulitis episode, and was satisfied with the results of normal breast conditions. Although further clinical studies are required to confirm efficacy, supermicrosurgical LVA has the potential to be an option for the treatment of progressive BLE refractory to conservative treatments.
Robust treatment planning with conditional value at risk chance constraints in intensity‐modulated proton therapy
Authors: An Yu , Liang Jianming , Schild Steven E. , Bues Martin , Liu Wei
Published: January 2017

Background and purpose

Intensity‐modulated proton therapy (IMPT) is highly sensitive to range uncertainties and uncertainties caused by setup variation. The conventional inverse treatment planning of IMPT based on the planning target volume (PTV) is not often sufficient to ensure robustness of treatment plans. We applied a probabilistic framework (chance‐constrained optimization) in IMPT planning to hedge against the influence of uncertainties.

Material and methods

We retrospectively selected one patient with lung cancer, one patient with head and neck (H&N) cancer, and one with prostate cancer for this analysis. Using their original images and prescriptions, we created new IMPT plans using two methods: (1) a robust chance‐constrained treatment planning method with the clinical target volume (CTV) as the target; (2) the margin‐based method with PTV as the target, which was solved by commercial software, CPLEX, using linear programming. For the first method, we reformulated the model into a tractable mixed‐integer programming problem and sped up the calculation using Benders decomposition. The dose‐volume histograms (DVHs) from the nominal and perturbed dose distributions were used to assess and compare plan quality. DVHs for all uncertain scenarios along with the nominal DVH were plotted. The width of the “bands” of DVHs was used to quantify the plan sensitivity to uncertainty. The newly developed Benders decomposition method was compared with a commercial solution to demonstrate its computational efficiency. The trade‐off between nominal plan quality and plan robustness was investigated.

Results

Our chance‐constrained model outperformed the PTV method in terms of tumor coverage, tumor dose homogeneity, and plan robustness. Our model was shown to produce IMPT plans to meet the dose‐volume constraints of organs at risk (OARs) and had better sparing of OARs than the PTV method in the three clinical cases included in this study. The chance‐constrained model provided a flexible tool for users to balance between plan robustness and plan quality. In addition, our in‐house developed method was found to be much faster than the commercial solution.

Conclusion

With explicit control of plan robustness, the chance‐constrained robust optimization model generated superior IMPT plans compared to the PTV‐based method.
Overlap‐guided fixed‐patient support positioning optimization for cranial SRT
Authors: MacDonald R. Lee , Robar James L. , Thomas Christopher G.
Published: January 2017

Purpose

To investigate potential dosimetric improvements through the optimization of fixed‐couch rotational position in cranial cancer stereotactic treatments.

Methods

Using previously delivered cranial stereotactic radiotherapy plans treated at the Nova Scotia Health Authority (NSHA), we have redesigned the treatment arrangement to find the optimal couch rotation positions based on the reduction of overlap between organs‐at‐risk of exposure (OARs) and target volume (PTV). Maintaining the gantry arrangements from the delivered treatment, the couch positions were determined based on a cost function analysis of accumulation of overlap score from an equation developed by Yang et al. and refined by MacDonald et al. The algorithm incorporates factors for radiation dose sensitivities of each OAR, depth of both OARs and target (PTV) volumes, and orthogonality of the 3D vector between OAR and PTV in the case of proximal OAR position.

Results

The plan evaluation was conducted on 16 acoustic neuroma patients treated with stereotactic radiotherapy plans at the NSHA. Maximum and mean doses to the OARs were reduced by approximately 14.30% ± 2.86% and 19.25% ± 2.10%, respectively, with application of this optimization technique as compared to the delivered treatment plans. In addition, PTV conformity and homogeneity were improved with application of this optimization technique.

Conclusion

This variation of the existing delivery techniques with guidance from a PTV‐OAR overlap cost function analysis technique can yield significant dosimetric improvements with no increase to delivery or planning time.
Computer‐aided detection of retained surgical needles from postoperative radiographs
Authors: Sengupta Aunnasha , Hadjiiski Lubomir , Chan Heang‐Ping , Cha Kenny , Chronis Nikolaos , Marentis Theodore C.
Published: January 2017

Purpose

Foreign objects, such as surgical sponges, needles, sutures, and other surgical instruments, retained in the patient's body can have dire consequences in terms of patient mortality as well as legal and financial penalties. We propose computer‐aided detection (CAD) on postoperative radiographs as a potential solution to reduce the chance of retained foreign objects (RFOs) after surgery, thus alleviating one of the major concerns for patient safety in the operation room. A CAD system can function as a second pair of eyes or a prescreener for the surgeon and radiologist, depending on the CAD system design and the workflow. In this work, we focus on the detection of surgical needles on postoperative radiographs. As needles are frequently observed RFOs, a CAD system that can offer high sensitivity and specificity toward detecting surgical needles will be useful.

Methods

Our CAD system incorporates techniques such as image segmentation, image enhancement, feature analysis, and curve fitting to detect surgical needles on radiographs. A dataset consisting of 108 cadaver images with a total of 116 needles and 100 cadaver “normal” images without needles was acquired with a portable digital x‐ray system. A reference standard was obtained by marking the needle locations using an in‐house developed graphical user interface. The 108 cadaver images with the needles were partitioned into a training set containing 53 cadaver images with 59 needles and a test set containing 55 cadaver images with 57 needles. All of the 100 cadaver normal images were reserved as a part of the test set and used to estimate the false‐positive detection rate. Two operating points were chosen from the CAD system such that it can be operated in two modes, one with higher specificity (mode I) and the other with higher sensitivity (mode II).

Results

For the training set, the CAD system with the rule‐based classifier achieved a sensitivity of 74.6% with 0.15 false positives per image (FPs/image) in mode I and a sensitivity of 89.8% with 0.36 FPs/image in mode II. For the test set, the CAD system achieved a sensitivity of 77.2% with 0.26 FPs/image in mode I and a sensitivity of 84.2% with 0.6 FPs/image in mode II. For comparison, the CAD system with the neural network classifier achieved a sensitivity of 74.6% with 0.08 FPs/image in mode I and a sensitivity of 88.1% with 0.28 FPs/image in mode II for the training set, and a sensitivity of 75.4% with 0.23 FPs/image in mode I and a sensitivity of 86.0% with 0.57 FPs/image in mode II for the test set.

Conclusion

A novel CAD system has been developed for automated detection of needles inadvertently left behind in a patient's body from postsurgery radiographs. The pilot system offers reasonable performance in both the high sensitivity and high specificity modes. This preliminary study shows the promise of CAD as a low‐cost and efficient aid for reducing retained surgical needles in patients.
Vitamin D levels are associated with gross motor function in amyotrophic lateral sclerosis
Authors: Paganoni Sabrina , Macklin Eric A. , Karam Chafic , Yu Hong , Gonterman Fernando , Fetterman K. Ashley , Cudkowicz Merit , Berry James , Wills Anne‐Marie
Published: January 2017

Introduction

The objective of this study was to determine whether serum vitamin D [25(OH)D] levels are associated with disease progression in amyotrophic lateral sclerosis (ALS).

Methods

25(OH)D was measured in subjects enrolled in a multicenter study for validation of ALS biomarkers. Baseline 25(OH)D levels were correlated with baseline ALSFRS‐R scores. Average 25(OH)D levels from baseline and month 6 visits (seasonally asynchronous) were used to predict subsequent rate of change in ALSFRS‐R from month 6 to month 18.

Results

Most subjects had either insufficient or deficient 25(OH)D levels. Lower 25(OH)D was associated with lower ALSFRS‐R gross motor scores, but not lower ALSFRS‐R total scores at baseline. Levels of 25(OH)D were not predictive of disease progression over the next 12 months.

Conclusion

25(OH)D was associated with baseline gross motor ALSFRS‐R scores but did not predict the rate of disease progression. Vitamin D levels may reflect poor mobility in patients with ALS. Muscle Nerve, 2017 Muscle Nerve 56: 726–731, 2017
The electrodiagnostic natural history of parsonage–turner syndrome
Authors: Feinberg Joseph H. , Nguyen Elizabeth T. , Boachie‐Adjei Kwadwo , Gribbin Caitlin , Lee Steve K. , Daluiski Aaron , Wolfe Scott W.
Published: January 2017

Introduction

Recovery from Parsonage–Turner syndrome (PTS) is generally favorable, although recovery times have been shown to vary, in part because there are no universally accepted outcome measures. In this study, we describe the electrodiagnostic natural history of this condition based on objective electrodiagnostic testing, and propose that complete electrodiagnostic recovery can be seen as early as 1 year.

Methods

Twenty‐six subjects with 29 affected nerves confirmed as PTS were followed every 3 months for electrodiagnostic testing, or until full reinnervation was confirmed.

Results

Twenty‐three cases (79.3%) demonstrated electrodiagnostic evidence of initial recovery at a mean of 5.8 months. Nine cases (31%) showed complete electrodiagnostic recovery at a mean of 1 year. When excluding cases with <1 year of follow‐up, 52.9% achieved complete electrodiagnostic recovery.

Conclusions

In contrast to previous reports, full electrodiagnostic recovery of PTS was demonstrated at a mean of 1 year in > 50% of patients with longer term follow‐up. Muscle Nerve 56: 737–743, 2017
Structural shape and topology optimization of cast parts using level set method
Authors: Wang Yaguang , Kang Zhan
Published: January 2017

This paper presents a level set‐based shape and topology optimization method for conceptual design of cast parts. In order to be successfully manufactured by the casting process, the geometry of cast parts should satisfy certain moldability conditions, which poses additional constraints in the shape and topology optimization of cast parts. Instead of using the originally point‐wise constraint statement, we propose a casting constraint in the form of domain integration over a narrowband near the material boundaries. This constraint is expressed in terms of the gradient of the level set function defining the structural shape and topology. Its explicit and analytical form facilitates the sensitivity analysis and numerical implementation. As compared with the standard implementation of the level set method based on the steepest descent algorithm, the proposed method uses velocity field design variables and combines the level set method with the gradient‐based mathematical programming algorithm on the basis of the derived sensitivity scheme of the objective function and the constraints. This approach is able to simultaneously account for the casting constraint and the conventional material volume constraint in a convenient way. In this method, the optimization process can be started from an arbitrary initial design, without the need for an initial design satisfying the cast constraint. Numerical examples in both 2D and 3D design domain are given to demonstrate the validity and effectiveness of the proposed method. Copyright © 2017 John Wiley & Sons, Ltd.
Temperature dependence of the electrical conductivity of poly(Anthranilic acid)/magnetite nanocomposites and the applicability of different conductivity models
Authors: Jayakrishnan P. , Ramesan M.T.
Published: January 2017

Electrically conductive composite materials based on poly(anthranilic acid) (PANA) and magnetite nanoparticles (Fe3O4) were prepared by in situ chemical oxidative polymerization. Emphasis was given to study the effect of varying concentration of nanoparticles on the magnetic property, AC and DC conductivity of the nanocomposite in a broad range of frequencies at various temperatures. HRTEM and XRD were used to support the variation of electrical conductivity of the composite. AC conductivity of PANA/Fe3O4 composites increase not only with the concentration of nanoparticles but also with the temperatures used in the study. The measured AC conductivity of composite materials showed a strong dependence on the frequency. The activation energy of the samples was calculated from the Arrhenius plots. DC conductivity of the nanocomposites increased with the increase in concentration of nanoparticles. The conductivity of nanocomposites were much higher than that of poly(anthranilic acid). The experimental values of the DC conductivity of composites were compared with the theoretical values using different models such as Scarisbrick, Bueche, McCullough equations. The theoretical conductivity of composite material from McCullough model was in good agreement with the experimentally determined conductivity. The magnetic properties of nanocomposites were studied using the vibration sample magnetometer. The saturation of magnetization increased with increasing the Fe3O4 content in the polymer composite. POLYM. COMPOS., 39:2791–2800, 2018. © 2016 Society of Plastics Engineers
Antiepileptic drugs and risk of suicide attempts: a case–control study exploring the impact of underlying medical conditions
Authors: Grimaldi‐Bensouda Lamiae , Nordon Clementine , Rossignol Michel , Jardon Vincent , Boss Virginie , Warembourg Frédérique , Reynolds Robert , Kurz Xavier , Rouillon Frédéric , Abenhaim Lucien ,   for the PROTECT‐WP6 study group
Published: January 2017

Purpose

Randomized‐controlled trials and claims databases suggest that antiepileptic drug (AED) use may increase the risk of suicide attempts (SA). The present case–control study explores the impact of underlying indications on this potential association.

Methods

Physicians collected the medical history; prior 12‐month drug use was obtained from standardized telephone interviews with patients. The association between AED use and SA was explored using multivariate conditional logistic regression. The analyses were replicated after stratification on depression and neurological disorders (epilepsy, migraine, and chronic neuropathic pain).

Results

Between 2008 and 2012, 506 adults with an incident SA were recruited in suicide treatment centers from across France and socio‐demographically matched to 2829 controls from primary care settings. The association between AED use and odds of SA was not significant overall (odds ratio [OR], 1.5; 95% confidence interval [CI], 0.9–2.4). No association was observed for patients with neurological disorders (OR, 1.1; 95%CI, 0.5–2.4) as opposed to patients with depression (OR, 1.6; 95%CI, 1.0–2.5), but unmeasured confounding was suspected.

Conclusions

Our results suggest that the association observed between AED use and increased odds of non‐fatal SA in patients with either a lifetime history of depression or no neurological disorder may be explained by the presence of an underlying psychiatric disorder. Accounting for underlying indications is crucial in drug safety studies, as these can cause a reported association (or lack thereof) to be misleading. This may require the prospective collection of medical data at a patient level. Copyright © 2017 John Wiley & Sons, Ltd.
Quantitative proteomics reveals EVA1A‐related proteins involved in neuronal differentiation
Authors: Zhong Lijun , Zhou Juntuo , Chen Xi , Liu Jiao , Liu Zhen , Chen Yingyu , Bai Yun
Published: January 2017

EVA1A is an autophagy‐related protein, which plays an important role in embryonic neurogenesis. In this study, we found that loss of EVA1A could decrease neural differentiation in the brain of adult Eva1a−/− mice. To determine the mechanism underlying this phenotype, we performed label‐free quantitative proteomics and bioinformatics analysis using the brains of Eva1a−/− and wild‐type mice. We identified 11 proteins that were up‐regulated and 17 that were down‐regulated in the brains of the knockout mice compared to the wild‐type counterparts. Bioinformatics analysis indicated that biological processes, including ATP synthesis, oxidative phosphorylation, and the TCA cycle, are involved in the EVA1A regulatory network. In addition, gene set enrichment analysis showed that neurodegenerative diseases, such as Alzheimer's disease and Huntington's disease, were strongly associated with Eva1a knockout. Western blot experiments showed changes in the expression of nicotinamide nucleotide transhydrogenase, an important mitochondrial enzyme involved in the TCA cycle, in the brains of Eva1a knockout mice. Our study provides valuable information on the molecular functions and regulatory network of the Eva1a gene, as well as new perspectives on the relationship between autography‐related proteins and neural differentiation.
Expanding the cerebrospinal fluid endopeptidome
Authors: Hansson Karl T. , Skillbäck Tobias , Pernevik Elin , Kern Silke , Portelius Erik , Höglund Kina , Brinkmalm Gunnar , Holmén‐Larsson Jessica , Blennow Kaj , Zetterberg Henrik , Gobom Johan
Published: January 2017

Biomarkers of neurodegenerative disorders are needed to assist in diagnosis, to monitor disease progression and therapeutic interventions, and to provide insight into disease mechanisms. One route to identify such biomarkers is by proteomic and peptidomic analysis of cerebrospinal fluid (CSF). In the current study, we performed an in‐depth analysis of the human CSF endopeptidome to establish an inventory that may serve as a basis for future targeted biomarker studies. High‐pH RP HPLC was employed for off‐line sample prefractionation followed by low‐pH nano‐LC‐MS analysis. Different software programs and scoring algorithms for peptide identification were employed and compared. A total of 18 031 endogenous peptides were identified at a FDR of 1%, increasing the number of known endogenous CSF peptides 10‐fold compared to previous studies. The peptides were derived from 2 053 proteins of which more than 60 have been linked to neurodegeneration. Notably, among the findings were six peptides derived from microtubule‐associated protein tau, three of which span the diagnostically interesting threonine‐181 (Tau‐F isoform). Also, 213 peptides from amyloid precursor protein were identified, 58 of which were partially or completely within the sequence of amyloid β 1–40/42, as well as 109 peptides from apolipoprotein E, spanning sequences that discriminate between the E2/E3/E4 isoforms of the protein.
Network meta‐analysis of probiotics to prevent respiratory infections in children and adolescents
Authors: Amaral Marina Azambuja , Guedes Gabriela Helena Barbosa Ferreira , Epifanio Matias , Wagner Mario Bernardes , Jones Marcus Herbert , Mattiello Rita
Published: January 2017

Probiotics have emerged as a promising intervention for the prevention of respiratory tract infections (RTIs) in children. Assess the effect of probiotics on prevention of RTIs in children and adolescents. MEDLINE, EMBASE, LILACS, SCIELO, CINAHL, SCOPUS, and Web of Science. Key words: “respiratory tract infections” AND probiotics. Randomized controlled trials RCT assessing the effect of probiotics on RTIs in children and adolescents were included. Two reviewers, working independently, to identify studies that met the eligibility criteria. Main and secondary outcomes were RTIs and adverse effects, respectively. Twenty‐one trials with 6.603 participants were included. Pairwise meta‐analysis suggested that Lactobacillus casei rhamnosus (LCA) was the only effective probiotic to the rate of RTIs compared to placebo (RR0.38; Crl 0.19–0.45). Network analysis showed that the LCA exhibited 54.7% probability of being classified in first, while the probability of Lactobacillus fermentum CECT5716 (LFC) being last in the ranking was 15.3%. LCA showed no better effect compared to other probiotic strains by indirect analysis. This systematic review found a lack of evidence to support the effect of probiotic on the incidence rate of respiratory infections in children and adolescents. Pediatr Pulmonol. 2017;52:833–843. © 2017 Wiley Periodicals, Inc.
Pilot study of dornase alfa (Pulmozyme) therapy for acquired ventilator‐associated infection in preterm infants
Authors: Scala Melissa , Hoy Deborah , Bautista Maria , Palafoutas Judith Jones , Abubakar Kabir
Published: January 2017

Sumary

Objective

Evaluate the feasibility, safety, and efficacy of adjunctive treatment with dornase alfa in preterm patients with ventilator‐associated pulmonary infection (VAPI) compared to standard care.

Working Hypothesis

We hypothesize that therapy with dornase alfa will be safe and well tolerated in the preterm population with no worsening of symptoms, oxygen requirement, or need for respiratory support.

Study Design

Prospective, randomized, blinded, pilot study comparing adjunctive treatment with dornase alfa to sham therapy. In addition to standard care, infants were randomized to receive dornase alfa 2.5 mg nebulized via endotracheal tube (ETT) every 12 hr for 7 days or sham therapy. ETT secretion gram stain and culture and chest X‐ray (CXR) findings were evaluated. Respiratory support data were downloaded from the ventilator.

Results

Fourteen infants developed VAPI between 2012 and 2014; 11 enrolled in the study. Six received dornase alfa and five received sham therapy. Average gestational age at birth was 25 weeks and age at study entry was 31 days. There were no differences in demographics, ETT white blood cell count (WBC), CXR, or mean airway pressure (MAP) between the two groups. There was a trend towards decreased oxygen requirement (FiO2) in the treatment group that did not reach statistical significance. No side effects were observed in the treatment group.

Conclusion

Treatment with dornase alfa is safe and treated infants had some improvement in FiO2 requirement but no improvement in MAP. A larger randomized trial is needed to evaluate the efficacy of this therapy. Pediatr Pulmonol. 2017; 52:787–791. © 2017 Wiley Periodicals, Inc.
Assessment of Physico‐Thermal Properties, Combustion Performance, and Ignition Delay Time of Dimethyl Amino Ethanol as a Novel Liquid Fuel
Authors: Pakdehi Shahram G. , Keshavarz Mohammad Hossein , Akbari Maryam , Ghorbani Mostafa
Published: January 2017

Dimethyl amino ethanol (DMAE) contains both hydroxyl and amino functional groups, which may be introduced as a new liquid fuel with high safety and less toxicity with respect to common high performance liquid fuels. Physico‐thermal properties, combustion performance and ignition delay time of DMAE are compared with the usual high performance liquid fuels as well as ethanol and dimethylamine. Combustion performances of DMAE (specific impulse at sea level) with common liquid oxidizers including white fuming nitric acid (WFNA), inhibited red fuming nitric acid (IRFNA), nitrogen tetroxide (N2O4), hydrogen peroxide (H2O2), liquid oxygen (LOX), and the mixed oxides of nitrogen (MON) are also evaluated. Maximum and minimum specific impulses of DMAE are obtained with LOX (299.6 s) and WFNA (262.4 s), respectively. Maximum density‐specific impulse is obtained with DMAE‐N2O4 bipropellant. The ignition delay time of DMAE with several liquid oxidizers are measured with open cup test method. DMAE‐WFNA and DMAE‐IRFNA bipropellants are hypergolic where their ignition delay times are 26 and 42 milliseconds, respectively.
Evaluation of 4‐(Dimethylsilyl) Butyl Ferrocene Grafted HTPB as a Burning Rate Modifier in Composite Propellant Formulation using Bicurative System
Authors: Kurva Ramesh , Gupta Garima , Dhabbe Kashinath I. , Jawale Lalita S. , Kulkarni Prasanth S. , Maurya Mehilal
Published: January 2017

High burning rate composite propellants are achieved by incorporation of fine particles of oxidizer, transition metal oxides, and liquid ballistic modifiers. However, they pose processing problems, inertness to the composition and migration related issues. To overcome such problems, an attempt was made to incorporate ferrocenyl grafted HTPB as a burning rate modifier by partly replacing HTPB from 10 % to 50 % using TDI/ IPDI bicurative system and to study their processability in terms of viscosity, mechanical, thermal, sensitivity, and ballistic properties. The data on viscosity reveal that there is a marginal enhancement in end of mix viscosity as percentage of ferrocenyl grafted HTPB increases. The mechanical data reveal that tensile strength and elastic modulus increases, whereas percentage elongation decreases compared to base composition. The results on thermal properties infer that, as the percentage of ferrocenyl grafted HTPB increases, onset decomposition temperature decreases. The impact and friction sensitivity data also envisage that sensitivity increases in comparison to base composition. The data on ballistic properties revealed that there is ca. 53 % increase in burning rate, while decrease in “n” value from 0.39 to 0.2 was obtained compared to base composition.
Examining the validity and sensitivity to change of the 5 and 10 sit‐to‐stand tests in people with multiple sclerosis
Authors: Nilsagård Ylva , Andreasson Malin , Carling Anna , Vesterlin Helena
Published: January 2017

Background and Purpose

Sit‐to‐stand transfers are frequently performed, and transfers have been associated with fall risk among people with multiple sclerosis (PwMS). There is limited research regarding the validity of sit‐to‐stand tests (STSs) in PwMS. The purpose of this study was to investigate the concurrent, divergent, and discriminant validity and sensitivity to change of the 5 and 10 STSs.

Methods

A repeated‐measurement design was used, with data collected before and directly after a 7‐week intervention, as well as prospectively reported near‐fall incidents and falls during a 14‐week period. One hundred two PwMS with a limited (≤200 m) but retained (≥20 m) walking ability were identified by physiotherapists at outpatient rehabilitation centres in 5 Swedish County Council areas and invited to participate in an intervention study. Of the 52 participants agreeing to participate and fulfilling the inclusion criteria, 47 managed the tests at baseline, and 39 of these returned complete fall diaries. The main outcomes were the Berg Balance Scale (BBS), Timed Up and Go test (TUG), 10‐m walk test, 2‐min walk test, Fatigue Scale for Motor and Cognitive Function, falls, near‐fall incidents, and use of walking aids.

Results

Correlations in the total sample were above .60 between the STSs and BBS, TUG, 10‐m walk test, and 2‐min walk test and above .50 between the STSs and total number of falls. Both tests discriminated between those who did and did not use walking aids for the TUG, but not between fallers and nonfallers. There were no significant correlations between the STSs and number of falls or near‐fall incidents. The STSs did not differentiate between participants with changed and unchanged results on the BBS.

Discussion

The 5 and 10 STSs are valid in PwMS with an Expanded Disability Status Scale score ≤6.0 but do not identify fallers and have limited ability to detect change. Copyright © 2017 John Wiley & Sons, Ltd.
Identification of metabolites of palmatine in rats after oral administration using ultra‐high‐performance liquid chromatography/quadrupole time‐of‐flight mass spectrometry
Authors: Wang Kun , Chai Liwei , Ding Liqin , Qiu Feng
Published: January 2017

Rationale

Palmatine (PAL), a protopalmatine alkaloid, is an active constituent in a number of medicinal plants. In order to obtain a comprehensive and systematic metabolic profile of PAL, we investigated its metabolites in plasma, liver tissue, bile, urine, and feces samples after intragastrical administration to Sprague‐Dawley rats with a dose of 100 mg/kg/day.

Methods

In this study, a rapid and sensitive method by ultra‐high‐performance liquid chromatography coupled with quadrupole time‐of‐flight mass spectrometry (UPLC/QTOF‐MS), and Metabolynx™ software with the mass defect filter (MDF) technique was developed for screening and identification of the metabolites. The structural elucidation of the metabolites was performed by comparing their molecular weights and fragment ions with those of the parent drug.

Results

As a result, a total of 58 metabolites were identified in rat biological samples including 46 metabolites in urine, 18 metabolites in plasma, 34 metabolites in bile, 26 metabolites in liver tissue, and 10 metabolites in feces. Among them, six major metabolites were fully confirmed using reference standards and others were identified by retention time, accurate mass and fragment ions.

Conclusions

These results indicated that phase I reactions (demethylation and hydroxylation) and phase II reaction (glucuronidation and sulfation) were the main metabolic pathways of PAL in vivo. This research enhances our understanding of metabolism of PAL in rats, and provides useful information on the action mechanism of PAL. Copyright © 2017 John Wiley & Sons, Ltd.
The role of sleep in cognitive processing: focusing on memory consolidation
Authors: Chambers Alexis M.
Published: January 2017

Research indicates that sleep promotes various cognitive functions, such as decision‐making, language, categorization, and memory. Of these, most work has focused on the influence of sleep on memory, with ample work showing that sleep enhances memory consolidation, a process that stores new memories in the brain over time. Recent psychological and neurophysiological research has vastly increased understanding of this process. Such work not only suggests that consolidation relies on plasticity‐related mechanisms that reactivate and stabilize memory representations, but also that this process may be experimentally manipulated by methods that target which memory traces are reactivated during sleep. Furthermore, aside from memory storage capabilities, memory consolidation also appears to reorganize and integrate memories with preexisting knowledge, which may facilitate the discovery of underlying rules and associations that benefit other cognitive functioning, including problem solving and creativity. WIREs Cogn Sci 2017, 8:e1433. doi: 10.1002/wcs.1433

This article is categorized under:

Psychology > Memory

Psychology > Learning

Neuroscience > Cognition
Adult gastric stem cells and their niches
Authors: Bartfeld Sina , Koo Bon‐Kyoung
Published: January 2017

Adult gastric stem cells replenish the gastric epithelium throughout life. Recent studies have identified diverse populations of stem cells, progenitor cells, and even differentiated cells that can regain stem cell capacity, so highlighting an unexpected plasticity within the gastric epithelium, both in the corpus and antrum. Two niches seem to co‐exist in the gastric unit: one in the isthmus region and the other at the base of the gland, although the precise features of the cell populations and the two niches are currently under debate. A variety of gastric organoid models have been established, providing new insights into niche factors required by the gastric stem cell populations. Here we review our current knowledge of gastric stem cell populations, their markers and interactions, important niche factors, and different gastric organoid systems. WIREs Dev Biol 2017, 6:e261. doi: 10.1002/wdev.261

This article is categorized under:

Adult Stem Cells, Tissue Renewal, and Regeneration > Tissue Stem Cells and Niches

Adult Stem Cells, Tissue Renewal, and Regeneration > Stem Cells and Disease

Adult Stem Cells, Tissue Renewal, and Regeneration > Environmental Control of Stem Cells