bluuebunny/crossref_metadata_2025 huggingface dataset:
Forensic analysis of automotive paint chips for the identification of the vehicle manufacturer, colour and year of production using electrothermal vaporization coupled to inductively coupled plasma optical emission spectrometry
Authors: Huang Lily , Beauchemin Diane
Published: June 2017

This robust method correctly identifies rusted paint samples for manufacturer and year of production using prediction models without any rusted paint.
High performance transparent in-plane silicon nanowire Fin-TFTs via a robust nano-droplet-scanning crystallization dynamics
Authors: Xu Mingkun , Wang Jimmy , Xue Zhaoguo , Wang Junzhuan , Feng Ping , Yu Linwei , Xu Jun , Shi Yi , Chen Kunji , Roca i Cabarrocas Pere
Published: June 2017

A robust nano-droplet-scanning crystallization of a-Si into a self-positioned and transparent Si nanowire array for high performance fin-like thin film transistors.
High-density defects on PdAg nanowire networks as catalytic hot spots for efficient dehydrogenation of formic acid and reduction of nitrate
Authors: Liu Hu , Yu Yongsheng , Yang Weiwei , Lei Wenjuan , Gao Manyi , Guo Shaojun
Published: June 2017

Controlling the surface defects of nanocrystals is a new way of tuning/boosting their catalytic properties.
Multi-walled boron nitride nanotubes as self-excited launchers
Authors: Li Yifan , Zhou Yi , Wu Yan , Huang Chengchi , Wang Long , Zhou Xuyan , Zhao Zhenyang , Li Hui
Published: June 2017

Multi-walled BNNTs with an appropriate initial offset spontaneously launch the innermost nanotube along their central axis at a fast speed.
A tactile sensor using single layer graphene for surface texture recognition
Authors: Chun Sungwoo , Choi Yeonhai , Suh Dong Ik , Bae Gi Yoon , Hyun Sangil , Park Wanjun
Published: June 2017

A flexible tactile sensor using single layer graphene that can detect surface texture based on a single sensor architecture.
Facile synthesis and the properties of novel cardo poly(arylene ether sulfone)s with pendent cycloaminium side chains as anion exchange membranes
Authors: Gong Feixiang , Wang Ruiqiang , Chen Xinbing , Chen Pei , An Zhongwei , Zhang Suobo
Published: June 2017

The structure of pendent cycloaminium side chains containing higher alkalinity of conductive groups was effective for improving the micro-phase separation of AEMs.
A novel Ir/CeO2–C nanoparticle electrocatalyst for the hydrogen oxidation reaction of alkaline anion exchange membrane fuel cells
Authors: Qin Bowen , Yu Hongmei , Chi Jun , Jia Jia , Gao Xueqiang , Yao Dewei , Yi Baolian , Shao Zhigang
Published: June 2017

A novel catalyst, 10% Ir/CeO2–C, shows better activity and durability for hydrogen oxidation reaction in base than that of 10% Ir/C. It would benefit from the oxophilic effect of ceria and the strong metal–support interaction between Ir and CeO2.
PDMS-based microfluidic devices using commoditized PCBs as masters with no specialized equipment required
Authors: Tu Jing , Qiao Yi , Feng Haiqing , Li Junji , Fu Jiye , Liang Fupeng , Lu Zuhong
Published: June 2017

A simple, convenient and reliable approach used to prepare general polymer PDMS-based microfluidic devices with a minimal requirement for equipment.
Production of exopolysaccharide by Bifidobacterium longum isolated from elderly and infant feces and analysis of priming glycosyltransferase genes
Authors: Yan Shuang , Zhao Guozhong , Liu Xiaoming , Zhao Jianxin , Zhang Hao , Chen Wei
Published: June 2017

Elder-originatedBifidobacterium longumstrains produced more cell-surface-bound exopolysaccharide (EPS-b) than infant-originated strains.
Ir/C and Brφnsted acid functionalized ionic liquids: an efficient catalytic system for hydrogenation of nitrobenzene to p-aminophenol
Authors: Wang Hong , Jiang Taotao , Ma Lei , Wang Hanbing , Xu Xiaoliang , Lu Chunshan , Li Xiaonian
Published: June 2017

Hydrogenation of nitrobenzene to p-aminophenol using Ir/C and Brφnsted acid functionalized ionic liquids as catalysts.
Electrochemical hydrogenated TiO2nanotube arrays decorated with 3D cotton-like porous MnO2enables superior supercapacitive performance
Authors: Liu Jiaqin , Xu Juan , Wang Yan , Cui Jiewu , Tan Hark Hoe , Wu Yucheng
Published: June 2017

Highly conducting TiO2nanotube arrays (EH-TNTAs) decorated with unique 3D cotton-like porous MnO2enables superior supercapacitive performance.
Feasibility of USPIOs for T1-weighted MR molecular imaging of tumor receptors
Authors: Liu Zhetao , Cai Jiali , Su Huilan , Yang Jingxing , Sun Wenshe , Ma Yongjie , Liu Shiyuan , Zhang Chunfu
Published: June 2017

USPIOs having a superior T1 contrast effect could only be used for T2-weighted, but not for T1-weighted MR tumor receptor imaging.
Hybrid CuxO–TiO2 porous hollow nanospheres: preparation, characterization and photocatalytic properties
Authors: Xiang Yingqiao , Li Yingying , Zhang Xintong , Zhou Annan , Jing Nan , Xu Qinghong
Published: June 2017

A series of CuxO–TiO2 hollow nanospherical composites with different mass percents of copper element were prepared, and the composites displayed high photocatalytic activities towards acetaldehyde degradation to CO2 under visible-light irradiations.
On the incompatibility of lithium–O2 battery technology with CO2
Authors: Zhang Shiyu , Nava Matthew J. , Chow Gary K. , Lopez Nazario , Wu Gang , Britt David R. , Nocera Daniel G. , Cummins Christopher C.
Published: June 2017

The peroxide dianion reacts with CO2 in polar aprotic organic media to afford the hydroperoxycarbonate and carbonate radical anions. These highly reactive species, if formed in lithium–O2 cells, can lead to cell degradation via oxidation of the electrolyte and electrode.
Ni/NiO nanoparticles on a phosphorous oxide/graphene hybrid for efficient electrocatalytic water splitting
Authors: Wang Juan , Xie Yanan , Yao Yuanying , Huang Xing , Willinger Marc , Shao Lidong
Published: June 2017

Ni/NiO nanoparticles on phosphorus oxide-incorporated holey graphene sheets showed efficient catalytic activity and stability for hydrogen evolution reaction.
Hierarchically structured, oxygen deficient, tungsten oxide morphologies for enhanced photoelectrochemical charge transfer and stability
Authors: Chen P. , Baldwin M. , Bandaru P. R.
Published: June 2017

The role of non-stoichiometry in hierarchically structured tungsten oxide compounds for enhancing the photoelectrochemical response and stability.
Graphene oxide based moisture-responsive biomimetic film actuators with nacre-like layered structures
Authors: Zhang Yaqian , Jiang Haoyang , Li Feibo , Xia Yanhong , Lei Yu , Jin Xianghu , Zhang Gongzheng , Li Huanjun
Published: June 2017

Hygroresponsive biomimetic actuators that convert chemical potential energy contained within the humidity gradient into mechanical deformation are of particular significance for realizing a sustainable society.
Targeting the Ras palmitoylation/depalmitoylation cycle in cancer
Authors: Lin David Tse Shen , Davis Nicholas G. , Conibear Elizabeth
Published: June 2017

The Ras proteins are well-known drivers of many cancers and thus represent attractive targets for the development of anticancer therapeutics. Inhibitors that disrupt the association of the Ras proteins with membranes by blocking the addition of the farnesyl lipid moiety to the Ras C-terminus failed in clinical trials. Here, we explore the possibility of targeting a second lipid modification, S-acylation, commonly referred to as palmitoylation, as a strategy to disrupt the membrane interaction of specific Ras isoforms. We review the enzymes involved in adding and removing palmitate from Ras and discuss their potential roles in regulating Ras tumorigenesis. In addition, we examine other proteins that affect Ras protein localization and may serve as future drug targets.
Synthesis of N-Sulfonyl Ynamido-Phosphonates: Valuable Partners for Cycloadditions
Authors: Perez Vincent , Fadel Antoine , Rabasso Nicolas
Published: June 2017

N-Sulfonyl ynamido-phosphonates were prepared from sulfonamides and bromo alkynylphosphonates through a direct copper-catalyzed coupling reaction. The substrates were obtained in good to excellent yields. The latter are valuable partners to react with nitrile-oxides­ to form isoxazoles in good yields and with an exclusive regio­selectivity.
Entwicklung und Validierung eines vollautomatischen, experimentellen Set-ups zur Ex-vivo-Berstungsdruckmessung nach chirurgischem Gefäßverschluss
Authors: Wallimann Herbert , Menges Pia , Hausen Bernard , Linder Albert
Published: June 2017

Hintergrund Die steigende Anzahl an endoskopischen Operationen zeitigt verschiedene Ansprüche an das operative Instrumentarium. Der wohl wichtigste Qualitätsparameter für Klammernahtgeräte ist der Berstungsdruck. Zu dessen Bestimmung finden sich in der Literatur verschiedene experimentelle Aufbauten. All diese Set-ups zeigen jedoch beträchtliche Kritikpunkte. Mit dieser Studie stellen wir ein vollautomatisches und untersucherunabhängiges Berstungsdruckmesssystem vor, das die Situation in vivo weitgehend imitiert. Das experimentelle Set-up zeichnet sich insbesondere dadurch aus, dass nicht nur ein komplettes Bersten registriert, sondern zuverlässig bereits eine sehr frühe – jedoch interventionspflichtige – Leckage detektiert wird (NID = niedrigster interventionspflichtiger Druck).

Material und Methode Die Berstungsdruckmessung erfolgte an Gefäßsegmenten von porcinen Aa. carotides communes, der Gefäßverschluss mit dem Klammernahtgerät MicroCutter XCHANGE® der Firma DexteraSurgical. Vor Verschluss wurde das Gefäßsegment mit Flüssigkeit bis zu einem Druck von 80 mmHg gefüllt. Die Flüssigkeit aus 56% Wasser und 44% Glyzerin ergab eine blutähnliche Viskosität von 4,31 ± 0,03 cP. Die Druckerhöhung nach Verschluss erfolgte mit einer definierten Flussrate von 5 ml/min. Eine interventionspflichtige Leckage wurde automatisch detektiert bei einer Abflachung der Druckkurve auf weniger als 5 mmHg/s.

Ergebnisse der Validierung Zur Validierung des Softwaresystems wurden insgesamt 30 Klammernahtreihen untersucht. Der visuell durch 2 unabhängige Untersucher ermittelte mittlere Berstungsdruck (mittlere NID) betrug 515,8 mmHg ± 236,3 mmHg. Der maximale lag bei 911 mmHg und der minimale bei 80 mmHg. Der elektronische Berstungsdruck betrug im Mittel 511,8 mmHg ± 239,1 mmHg. Der maximale Druck betrug 911 mmHg und der minimale 80 mmHg. Statistisch zeigte sich eine signifikante Korrelation zwischen dem visuellen und dem elektronischen Berstungsdruck.

Schlussfolgerung Mit dem hier vorgestellten Testaufbau gelingt erstmals eine systematische Berstungsdruckmessung, die komplett automatisiert und untersucherunabhängig ist. Der definierte intravasale Druck vor dem Verschluss und die Flüssigkeit mit blutähnlicher Viskosität erlauben es, die intraoperativen Gegebenheiten weitgehend zu imitieren. Durch Definition des Berstungsdrucks als erstes Auftreten einer interventionspflichtigen Leckage (= niedrigster interventionspflichtiger Druck, NID) und nicht als komplettes Bersten lassen sich die Ergebnisse auf den chirurgischen Alltag übertragen.
Was sind Barrieren der Ernährungstherapie bei mangelernährten, hospitalisierten Patienten der Inneren Medizin?
Authors: Tribolet Pascal , Fehr Rebecca , Bächli Valerie , Geiser Martina , Toplak Hermann , Stanga Zeno , Schuetz Philipp
Published: June 2017

Hintergrund Die Mangelernährung ist im Spitalalltag ein zentrales Problem und korreliert mit Komplikationen, längeren Spitalaufenthalten und schlechteren Outcomes. Zur Reduktion dieser negativen Aspekte ist ein Ernährungsmanagement bei Risikopatienten sinnvoll, doch die Effizienz dieser Maßnahme ist variabel und es existieren verschiedene Barrieren zur optimalen Umsetzung von Ernährungsinterventionen im Alltag. Das Ziel dieser Studie ist es, die Umsetzbarkeit eines neu etablierten Ernährungsalgorithmus im klinischen Spitalalltag zu überprüfen und potenzielle Barrieren einer Ernährungstherapie aufzuzeigen.

Methode Dies ist eine Beobachtungssubstudie des EFFORT-Trials, eine schweizweite, multizentrische, randomisierte, kontrollierte Interventionsstudie, welche den Effekt der Ernährungstherapie auf den Krankheitsverlauf von mangelernährten, hospitalisierten, medizinischen Patienten untersucht. Die untersuchte Population wurde anhand eines klar definierten Ernährungsalgorithmus behandelt, mit dem Ziel, eine bedarfsdeckende Energie- und Proteinzufuhr zu gewährleisten. Anhand von Essprotokollen wurde die Energie- und Proteinzielerreichung berechnet. Um die Assoziation zwischen dem Nichterreichen der Energie- und Proteinziele und vordefinierten Prädiktoren aufzuzeigen, wurde eine multivariate, logistische Regression durchgeführt.

Ergebnisse 581 Patienten wurden in die Analyse eingeschlossen. Die Ernährungsziele wurden insgesamt gut erreicht: 83,3 % aller eingeschlossenen Patienten erreichten an mindestens 1 der ersten 5 Spitaltage die Energieziele und 78,7 % die Proteinziele. In der multivariaten Regressionsanalyse war die Zielerreichung in Abhängigkeit von Alter, Geschlecht, Hauptdiagnose und Komorbiditäten nicht unterschiedlich. Lediglich die positive Antwort auf den Appetitverlust hat sich bei der Energiezielerreichung als protektiver Faktor gezeigt (Odds Ratio [OR] Appetitverlust: 0,53; 95 %-KI: 0,3 – 0,94; p = 0,03). Bei den Proteinzielen war der höhere BMI ein Risikofaktor für das Nichterreichen der Ziele (OR pro BMI-Einheit [kg/m2]: 1,05; 95 %-KI: 1,01 – 1,09; p = 0,02).

Schlussfolgerungen Der vorgeschlagene Ernährungsalgorithmus ist in der Praxis gut anwendbar und eine Großzahl von hospitalisierten Patienten der medizinischen Abteilung konnten die Ernährungsziele mit rein oralen Maßnahmen (Spitalküche und orale Supplemente), ohne Notwendigkeit einer Eskalation auf enterale oder parenterale Ernährung erreichen. Bei Risikopatienten sollte ein individuelles Assessment stattfinden, um zu klären, wie die Ernährungsziele erreicht werden können.
Knochendichtemessung und osteologische Laborparameter im klinischen Alltag
Authors: Warnecke Katja
Published: June 2017

Eine Osteoporose geht zunächst ohne Symptome einher. Bei Patienten mit Rückenschmerzen, Körpergrößeneinbuße, Frakturen ohne adäquates Trauma oder entsprechendem Risikoprofil sollte an eine Osteoporose gedacht werden. Die klinische Untersuchung, Bildgebung, Basislabor und Knochendichtemessung bilden die diagnostische Basis. Die Knochendichtemessung sowie die weiterführende Diagnostik und die leitliniengerechte spezifische osteologische Therapie sollten in erfahrenen Zentren durchgeführt werden.

Der Refresher gibt einen Überblick zu den diagnostischen Maßnahmen, einen Ausblick auf die Therapie sowie den Eckpfeilern der Osteoporoseprophylaxe, die ebenso selbstverständlich werden sollte wie die Primärprävention kardiovaskulärer Erkrankungen.
„Wir sollten voneinander lernen“
Authors: Niklas Anke
Published: June 2017

Prof. Karin Kraft hat seit 2002 die Stiftungsprofessur für Naturheilkunde an der Universitätsmedizin Rostock inne. Im zkm-Gespräch erzählt die Internistin u. a., warum dauerhaft stiftungsfinanzierte Lehrstühle für Naturheilkunde in Deutschland keine gute Entwicklung sind, welche Probleme die Abgabe von Phytoextrakten in Form von Botanicals mit sich bringt und wie ein Kur- und Heilwald therapeutisch genutzt werden kann.
Improved cross-calibration of Thomson scattering and electron cyclotron emission with ECH on DIII-D
Authors: Brookman M. W. , Austin M. E. , McLean A. G. , Carlstrom T. N. , Hyatt A. W. , Lohr J.
Published: June 2017

Thomson scattering produces ne profiles from measurement of scattered laser beam intensity. Rayleigh scattering provides a first calibration of the relation ne ∝ ITS, which depends on many factors (e.g., laser alignment and power, optics, and measurement systems). On DIII-D, the ne calibration is adjusted against an absolute ne from the density-driven cutoff of the 48 channel 2nd harmonic X-mode electron cyclotron emission system. This method has been used to calibrate Thomson ne from the edge to near the core (r/a > 0.15). Application of core electron cyclotron heating improves the quality of cutoff and depth of its penetration into the core, and also changes underlying MHD activity, minimizing crashes which confound calibration. Less fueling is needed as “ECH pump-out” generates a plasma ready to take up gas. On removal of gyrotron power, cutoff penetrates into the core as channels fall successively and smoothly into cutoff.
Selection of internal wave beam directions by a geometric constraint provided by topography
Authors: Chen Zhiwu , Xie Jieshuo , Xu Jiexin , He Yinghui , Cai Shuqun
Published: June 2017

Direct numerical simulations are performed to investigate the generation of internal waves in a linearly stratified fluid by oscillating barotropic flows over a model continental shelf-slope topography. The presence of a third wave-beam emitted from an abrupt shelf break and transverse to the topography, which has not been adequately interpreted, is now explained in terms of a geometric constraint provided by the topography. This explanation applies to wave beam selection at any abrupt topographic junction point, no matter whether it is convex or concave, or its nearby slope is subcritical or supercritical. One exception is that, at an abrupt concave point with a nearby supercritical slope, the blocking effect leads to the presence of “dead water” (i.e., no flow) and thus no wave beam is emitted. On a critical slope, two beams with opposite directions are emitted from an amphidromic point that has a distinct distance from the shelf break. In addition to the internal wave dispersion relation that restricts possible wave beam directions to form an X-pattern, the geometric constraint proposed in the present work serves as a second selection mechanism that further restricts wave beam directions. The reflective direction of a wave beam incident onto a slope can also be explained by this geometric constraint. The present work provides an updated explanation of internal wave beams emitted at abrupt topographic junction points and unifies the explanation of the wave beam direction for both wave generation and reflection processes.
Influence of the organic film thickness on the second order distributed feedback resonator properties of an organic semiconductor laser
Authors: Bencheikh F. , Sandanayaka A. S. D. , Matsushima T. , Ribierre J. C. , Adachi C.
Published: June 2017

We report on the cavity numerical characterization of a second order one-dimensional distributed feedback organic laser. The gain medium containing 6 wt. % of 4,4′-bis[(N-carbazole)styryl]biphenyl) in a 4,4′-bis[9-dicarbazolyl]-2,2′-biphenyl) host is vacuum deposited to form an organic thin film on a SiO2 grating. The influence of the organic film thickness on the properties of the resonant cavity is investigated through numerical calculations of both the confinement factor Γ and the Q-factor. The Q-factor is obtained using two methods, one by calculating the eigenmodes of the resonant cavity and the other by calculating the reflection spectrum. It was found that while the Γ increases with the organic film thickness, the Q-factor shows a non-monotonic function with a maximum value for a thickness of 200 nm.
Hartree-Fock theory with a self-generated magnetic field
Authors: Comelli S. , García-Cervera C. J.
Published: June 2017

We prove the existence of a ground state within the Hartree-Fock theory for atoms and molecules, in the presence of self-generated magnetic fields, with and without direct spin coupling. The ground state exists provided that the total charge Z of the K nuclei exceeds N, where N is the number of electrons, and, in the spin-polarized case, provided in addition that the nuclear charge is not too high.
Exosomes purified from a single cell type have diverse morphology
Authors: Zabeo Davide , Cvjetkovic Aleksander , Lässer Cecilia , Schorb Martin , Lötvall Jan , Höög Johanna L
Published: June 2017

Extracellular vesicles (EVs) are produced by all known organisms and are important for cell communication and physiology. Great morphological diversity has been described regarding EVs found in body fluids such as blood plasma, breast milk, and ejaculate. However, a detailed morphological analysis has never been performed on exosomes when purified from a single cell type.

In this study we analysed and quantified, via multiple electron microscopy techniques, the morphology of exosomes purified from the human mast cell line HMC‐1. The results revealed a wide diversity in exosome morphology, suggesting that subpopulations of exosomes with different and specific functions may exist. Our findings imply that a new, more efficient way of defining exosome subpopulations is necessary. A system was proposed where exosomes were classified into nine different categories according to their size and shape. Three additional morphological features were also found in exosomes regardless of their morphological classification.

These findings show that exosomes purified from a single cell line are also morphologically diverse, similar to previous observations for EVs in body fluids. This knowledge can help to improve the interpretation of experimental results and widen our general understanding of the biological functions of exosomes.
Incorporating Dynamic Assessment of Fluid Responsiveness Into Goal-Directed Therapy: A Systematic Review and Meta-Analysis
Authors: Bednarczyk Joseph M. , Fridfinnson Jason A. , Kumar Anand , Blanchard Laurie , Rabbani Rasheda , Bell Dean , Funk Duane , Turgeon Alexis F. , Abou-Setta Ahmed M. , Zarychanski Ryan
Published: June 2017

Objective:

Dynamic tests of fluid responsiveness have been developed and investigated in clinical trials of goal-directed therapy. The impact of this approach on clinically relevant outcomes is unknown. We performed a systematic review and meta-analysis to evaluate whether fluid therapy guided by dynamic assessment of fluid responsiveness compared with standard care improves clinically relevant outcomes in adults admitted to the ICU.

Data Sources:

Randomized controlled trials from MEDLINE, EMBASE, CENTRAL, clinicaltrials.gov, and the International Clinical Trials Registry Platform from inception to December 2016, conference proceedings, and reference lists of relevant articles.

Study Selection:

Two reviewers independently identified randomized controlled trials comparing dynamic assessment of fluid responsiveness with standard care for acute volume resuscitation in adults admitted to the ICU.

Data Extraction:

Two reviewers independently abstracted trial-level data including population characteristics, interventions, clinical outcomes, and source of funding. Our primary outcome was mortality at longest duration of follow-up. Our secondary outcomes were ICU and hospital length of stay, duration of mechanical ventilation, and frequency of renal complications. The internal validity of trials was assessed in duplicate using the Cochrane Collaboration’s Risk of Bias tool.

Data Synthesis:

We included 13 trials enrolling 1,652 patients. Methods used to assess fluid responsiveness included stroke volume variation (nine trials), pulse pressure variation (one trial), and stroke volume change with passive leg raise/fluid challenge (three trials). In 12 trials reporting mortality, the risk ratio for death associated with dynamic assessment of fluid responsiveness was 0.59 (95% CI, 0.42–0.83; I
2 = 0%; n = 1,586). The absolute risk reduction in mortality associated with dynamic assessment of fluid responsiveness was –2.9% (95% CI, –5.6% to –0.2%). Dynamic assessment of fluid responsiveness was associated with reduced duration of ICU length of stay (weighted mean difference, –1.16 d [95% CI, –1.97 to –0.36]; I
2 = 74%; n = 394, six trials) and mechanical ventilation (weighted mean difference, –2.98 hr [95% CI, –5.08 to –0.89]; I
2 = 34%; n = 334, five trials). Three trials were adjudicated at unclear risk of bias; the remaining trials were at high risk of bias.

Conclusions:

In adult patients admitted to intensive care who required acute volume resuscitation, goal-directed therapy guided by assessment of fluid responsiveness appears to be associated with reduced mortality, ICU length of stay, and duration of mechanical ventilation. High-quality clinical trials in both medical and surgical ICU populations are warranted to inform routine care.
Targeting activated protein C to treat hemophilia
Authors: Polderdijk Stéphanie G.I. , Baglin Trevor P. , Huntington James A.
Published: June 2017

Purpose of review

Hemophilia is a debilitating disease, marked by frequent, painful bleeding events, joint deterioration and early death. All current treatments consist of i.v. infusions of replacement factor or other procoagulant factors, and are incompletely effective, due in part to the short half-lives of the proteins. An alternative approach is to rebalance hemostasis by inhibiting natural anticoagulant mechanisms. In this article, we explain why activated protein C (APC) is an appropriate and safe target for the treatment of hemophilia.

Recent findings

A serpin (serine protease inhibitor) was engineered to specifically inhibit APC and was found to rescue hemostasis in a hemophilia mouse model, even after a severe tail clip injury. However, APC is also anti-inflammatory and has cytoprotective activities, raising safety concerns over the use of an APC inhibitor to treat hemophilia. We summarize the molecular basis of the anticoagulant and signaling activities of APC to assess the potential impact of targeting APC.

We conclude that the signaling and anticoagulant functions of APC are in spatially and kinetically distinct compartments, and that it is possible to specifically inhibit the anticoagulant activity of APC. Targeting APC with a serpin is remarkably effective and may be safe for long-term prophylactic use in the treatment of hemophilia.
3D Printing: current use in facial plastic and reconstructive surgery
Authors: Hsieh Tsung-yen , Dedhia Raj , Cervenka Brian , Tollefson Travis T.
Published: June 2017

Purpose of review

To review the use of three-dimensional (3D) printing in facial plastic and reconstructive surgery, with a focus on current uses in surgical training, surgical planning, clinical outcomes, and biomedical research. To evaluate the limitations and future implications of 3D printing in facial plastic and reconstructive surgery.

Recent findings

Studies reviewed demonstrated 3D printing applications in surgical planning including accurate anatomic biomodels, surgical cutting guides in reconstruction, and patient-specific implants fabrication. 3D printing technology also offers access to well tolerated, reproducible, and high-fidelity/patient-specific models for surgical training. Emerging research in 3D biomaterial printing have led to the development of biocompatible scaffolds with potential for tissue regeneration in reconstruction cases involving significant tissue absence or loss. Major limitations of utilizing 3D printing technology include time and cost, which may be offset by decreased operating times and collaboration between departments to diffuse in-house printing costs

The current state of the literature shows promising results, but has not yet been validated by large studies or randomized controlled trials. Ultimately, further research and advancements in 3D printing technology should be supported as there is potential to improve resident training, patient care, and surgical outcomes.
Motherhood and Risk for Human Immunodeficiency Virus/Sexually Transmitted Infections Among Female Sex Workers in the Mexico-US Border Region
Authors: Servin Argentina E. , Reed Elizabeth , Brouwer Kimberly C. , Magis-Rodriguez Carlos , Boyce Sabrina , Strathdee Steffanie A. , Silverman Jay G.
Published: June 2017

Background

Globally, female sex workers (FSWs) have been identified as a high-risk group for human immunodeficiency virus (HIV) and sexually transmitted infections (STIs). However, as women of reproductive age, FSWs also have children. Few studies have investigated if financial responsibilities associated with motherhood increase women’s vulnerability to HIV and STIs among FSWs.

Methods

From March 2013 to March 2014, 603 FSWs aged ≥18 years were recruited from Tijuana and Ciudad Juarez (Mexico) to participate in a study assessing HIV/STI risk environments.

Results

Findings from logistic regression models indicate that FSWs who reported motherhood were more likely to report (in the past 30 days): a higher client volume (>30 clients) (adjusted odds ratio [AOR], 1.91; 95% confidence interval [CI], 1.27–2.87) and always using alcohol right before or during sex with clients in the past 30 days (AOR, 1.77; 95% CI, 1.19–2.61). In contrast, they were more likely to report consistent condom use for vaginal or anal sex with clients (AOR, 1.68; 95% CI, 1.10–2.55), less likely to report using drugs right before or during sex with clients (AOR, 0.38; 95% CI, 0.26–0.56) and less likely to have tested positive for STIs at baseline (AOR, 0.63; 95% CI, 0.43–0.91).

Conclusions

These results provide a glimpse of the complex relationship between motherhood and women who are sex workers. Understanding the convergence of motherhood and sex work and how this can influence a woman’s decision when engaging in sex work and affect her health is essential to designing effective programs addressing reduce risk for HIV and STIs among FSWs in this region and elsewhere.
Brief Report: Peripheral Monocyte/Macrophage Phenotypes Associated With the Evolution of Cognitive Performance in HIV-Infected Patients
Authors: Fabbiani Massimiliano , Muscatello Antonio , Perseghin Paolo , Bani Marco , Incontri Arianna , Squillace Nicola , Lapadula Giuseppe , Gori Andrea , Bandera Alessandra
Published: June 2017

Background:

The contribution of monocyte activation in the development of HIV-associated neurocognitive disorders is not completely understood. This study aimed to explore the predictive value of peripheral monocyte/macrophage (M/M) phenotypes on the evolution of cognitive performance in a population of virologically suppressed HIV-infected patients.

Setting:

Prospective, observational, longitudinal study.

Methods:

HIV-1-infected patients with HIV-RNA <50copies/mL for >12 months underwent neuropsychological examination at baseline and after 1 year. Cognitive performance was evaluated using Z-transformed scores, and neurocognitive impairment (NCI) was defined according to Frascati criteria. Peripheral M/M phenotypes (classic CD14++CD16−, intermediate CD14++CD16+, and nonclassic CD14+CD16++) and specific surface activation markers (eg, CD163, CD11b, and CD38) were evaluated using flow cytometry at baseline. Predictive value of peripheral M/M phenotypes on the evolution of cognitive performance over 1-year follow-up was also evaluated.

Results:

Overall, 54 patients [85.2% men, median age 50 years (range 27–60 years), 27.8% hepatitis C virus coinfected, 48.1% with past AIDS-defining events, median nadir CD4 83 cells/μL (range 1–334), median baseline CD4 547 cells/μL (range 136–1652)] were enrolled. Proportion of patients with NCI was low, accounting for 13% at baseline and 16.5% after 1 year (P = 0.687). Memory was the only single domain in which decreased performance after 1 year was observed (−0.25 Z-score, P = 0.025). In patients with significant decrease (≥0.5 SD) in memory performance (n = 20), significantly lower CD14++CD16+CD163+ (% CD14++CD16+) (P = 0.038) and higher CD14+CD38+ (% CD14+) (P = 0.030) levels were observed.

Conclusions:

In virologically suppressed HIV-infected patients, the evolution of memory performance could be linked to the expression of certain peripheral activated M/M phenotypes. Such associations should be verified in larger populations over the long term.
An Overview of Cardiac Computed Tomography in Adults With Congenital Heart Disease
Authors: Suranyi Pal , Varga-Szemes Akos , Hlavacek Anthony M.
Published: June 2017

Familiarity with congenital heart disease (CHD) and its manifestations in adults is becoming increasingly important for the practicing cardiothoracic imager. The use of computed tomographic angiography is becoming commonplace not only in adults with a history and subsequent interventions for CHD as a child but also in de novo detection of—typically—milder, survivable forms of CHD, which are clinically suspected because of declining cardiac performance, cardiac events, or murmurs. Occasionally, adult CHD (ACHD) is found incidentally on scans performed for other indications (eg, trauma or neoplasm staging) because of improvements in computed tomographic technology and advanced visualization. A growing number of patients with CHD survive into adulthood and lead essentially normal lives all over the world and may present in community hospitals and emergency rooms to receive care. Advancements in computed tomographic angiography technology have further allowed us to individually tailor cardiovascular scans according to the patient’s anatomy and specifically for the clinical question raised, aiming at reduced exposure to iodinated contrast and radiation dose, while obtaining diagnostic-quality images. This task, however, is not simple. There is no one-size-fits-all cardiac scan that serves as a one-stop shop for ACHD patients. Careful planning and patient preparation, close supervision of the scan, sophisticated postprocessing, and interdisciplinary interpretation of the findings are all required ingredients for managing patients with ACHD. In this review we highlight the technical principles that should be observed to optimize imaging in ACHD. We also provide practical insight into how specific clinical questions can be answered utilizing this technology in the most frequently encountered forms of ACHD.
The Optimization of Short-Term Hepatocyte Preservation Before Transplantation
Authors: Fukuoka Kengo , Inagaki Akiko , Nakamura Yasuhiro , Matsumura Muneyuki , Yoshida Satoru , Imura Takehiro , Igarashi Yasuhiro , Miyagi Shigehito , Ohashi Kazuo , Enosawa Shin , Kamei Takashi , Unno Michiaki , Ohuchi Noriaki , Satomi Susumu , Goto Masafumi
Published: June 2017

Background

No optimal methods for short-term hepatocyte preservation have been established. We have recently developed a prominent oxygen-permeable bag (Tohoku Device [TD]) for pancreatic islet culture and transplantation. In this study, we investigated whether TD is also effective for hepatocyte preservation and tried to optimize other conditions.

Methods

Hepatocytes were preserved in the following conditions, and their outcomes were observed. First, the effectiveness of TD was investigated. Second, hepatocyte medium (HM) and organ preservation solutions with or without fetal bovine serum (FBS) were compared. Third, as supplementations, FBS and human serum albumin (HSA) were compared. Fourth, low, room and high temperature were compared. And finally, hepatocytes preserved in various conditions were transplanted into the subrenal capsule space of nonalbumin rats and engrafted areas were assessed.

Results

The survival rate of hepatocytes preserved in TD tended to be higher and their viability and function were maintained significantly greater than those of non-TD group. Irrespective of FBS supplementation, the survival rate of HM group was significantly higher than those of organ preservation solution group while viabilities and plating efficiency were similar among them. Although survival rates of groups without FBS were extremely low, results of HSA supplemented group were not inferior to FBS supplemented group. Hepatocytes preserved at high temperature had the worst results. The engrafted area of TD group tended to be higher than those of other groups.

Conclusions

TD is effective for short-term hepatocyte preservation. HSA is a useful substitute for FBS, and preserving in HM at low temperature is recommended.
Membrane-spanning α-helical barrels as tractable protein-design targets
Authors: Niitsu Ai , Heal Jack W. , Fauland Kerstin , Thomson Andrew R. , Woolfson Derek N.
Published: June 2017

The rational (
de novo
) design of membrane-spanning proteins lags behind that for water-soluble globular proteins. This is due to gaps in our knowledge of membrane-protein structure, and experimental difficulties in studying such proteins compared to water-soluble counterparts. One limiting factor is the small number of experimentally determined three-dimensional structures for transmembrane proteins. By contrast, many tens of thousands of globular protein structures provide a rich source of ‘scaffolds’ for protein design, and the means to garner sequence-to-structure relationships to guide the design process. The α-helical coiled coil is a protein-structure element found in both globular and membrane proteins, where it cements a variety of helix–helix interactions and helical bundles. Our deep understanding of coiled coils has enabled a large number of successful
de novo
designs. For one class, the α-helical barrels—that is, symmetric bundles of five or more helices with central accessible channels—there are both water-soluble and membrane-spanning examples. Recent computational designs of water-soluble α-helical barrels with five to seven helices have advanced the design field considerably. Here we identify and classify analogous and more complicated membrane-spanning α-helical barrels from the Protein Data Bank. These provide tantalizing but tractable targets for protein engineering and
de novo
protein design.

This article is part of the themed issue ‘Membrane pores: from structure and assembly, to medicine and technology’.
Computational studies of peptide-induced membrane pore formation
Authors: Lipkin Richard , Lazaridis Themis
Published: June 2017

A variety of peptides induce pores in biological membranes; the most common ones are naturally produced antimicrobial peptides (AMPs), which are small, usually cationic, and defend diverse organisms against biological threats. Because it is not possible to observe these pores directly on a molecular scale, the structure of AMP-induced pores and the exact sequence of steps leading to their formation remain uncertain. Hence, these questions have been investigated via molecular modelling. In this article, we review computational studies of AMP pore formation using all-atom, coarse-grained, and implicit solvent models; evaluate the results obtained and suggest future research directions to further elucidate the pore formation mechanism of AMPs.

This article is part of the themed issue ‘Membrane pores: from structure and assembly, to medicine and technology’.
Real-time dynamics of carbon nanotube porins in supported lipid membranes visualized by high-speed atomic force microscopy
Authors: Zhang Yuliang , Tunuguntla Ramya H. , Choi Pyung-On , Noy Aleksandr
Published: June 2017

In-plane mobility of proteins in lipid membranes is one of the fundamental mechanisms supporting biological functionality. Here we use high-speed atomic force microscopy (HS-AFM) to show that a novel type of biomimetic channel—carbon nanotube porins (CNTPs)—is also laterally mobile in supported lipid membranes, mimicking biological protein behaviour. HS-AFM can capture real-time dynamics of CNTP motion in the supported lipid bilayer membrane, build long-term trajectories of the CNTP motion and determine the diffusion coefficients associated with this motion. Our analysis shows that diffusion coefficients of CNTPs fall into the same range as those of proteins in supported lipid membranes. CNTPs in HS-AFM experiments often exhibit ‘directed’ diffusion behaviour, which is common for proteins in live cell membranes.

This article is part of the themed issue ‘Membrane pores: from structure and assembly, to medicine and technology’.
Restoring wild type-like network dynamics and behaviour during adulthood in a mouse model of schizophrenia
Authors: Marissal Thomas , Salazar Rodrigo F. , Bertollini Cristina , Mutel Sophie , De Roo Mathias , Rodriguez Ivan , Müller Dominique , Carleton Alan
Published: June 2017

Schizophrenia is a severely debilitating neurodevelopmental disorder. Establishing a causal link between circuit dysfunction and particular behavioural traits relevant to schizophrenia is crucial to shed new light on the mechanisms underlying the pathology. Here we studied an animal model of the 22q11 deletion syndrome, which is the highest genetic risk to develop the pathology. We report a desynchronization of hippocampal neuronal assemblies that resulted from parvalbumin interneuron hypoexcitability. Rescuing parvalbumin interneuron excitability with pharmacological or chemogenetic approaches is sufficient to restore wild type-like network dynamics and behaviour during adulthood. In conclusion, our data provide mechanistic insights underlying network dysfunction relevant to schizophrenia and demonstrate the potential of reverse engineering in fostering new therapeutic strategies to alleviate the burden of neurodevelopmental disorders.
A computational model that explores the effect of environmental geometries on grid cell representations
Authors: Jayakumar Samyukta , Narayanamurthy Rukhmani , Ramesh Reshma , Soman Karthik , Muralidharan Vignesh , Chakravarthy V. Srinivasa
Published: June 2017

Grid cells are a special class of spatial cells found in the medial entorhinal cortex (MEC) characterized by their strikingly regular hexagonal firing fields. This spatially periodic firing pattern was originally considered to be invariant to the geometric properties of the environment. However, this notion was contested by examining the grid cell periodicity in environments with different polarity (Krupic et al 2015) and in connected environments (Carpenter et al 2015). Aforementioned experimental results demonstrated the dependence of grid cell activity on environmental geometry. Analysis of grid cell periodicity on practically infinite variations of environmental geometry imposes a limitation on the experimental study. Hence we analyze the grid cell periodicity from a computational point of view using a model that was successful in generating a wide range of spatial cells, including grid cells, place cells, head direction cells and border cells. We simulated the model in four types of environmental geometries such as: 1) connected environments, 2) convex shapes, 3) concave shapes and 4) regular polygons with varying number of sides. Simulation results point to a greater function for grid cells than what was believed hitherto. Grid cells in the model code not just for local position but also for more global information like the shape of the environment. The proposed model is interesting not only because it was able to capture the aforementioned experimental results but, more importantly, it was able to make many important predictions on the effect of the environmental geometry on the grid cell periodicity.
The multidrug-resistance transporter MdfA fromEscherichia coli: crystallization and X-ray diffraction analysis
Authors: Nagarathinam Kumar , Jaenecke Frank , Nakada-Nakura Yoshiko , Hotta Yunhon , Liu Kehong , Iwata So , Stubbs Milton T. , Nomura Norimichi , Tanabe Mikio
Published: June 2017

The active efflux of antibiotics by multidrug-resistance (MDR) transporters is a major pathway of drug resistance and complicates the clinical treatment of bacterial infections. MdfA is a member of the major facilitator superfamily (MFS) fromEscherichia coliand provides resistance to a wide variety of dissimilar toxic compounds, including neutral, cationic and zwitterionic substances. The 12-transmembrane-helix MdfA was expressed as a GFP-octahistidine fusion protein with a TEV protease cleavage site. Following tag removal, MdfA was purified using two chromatographic steps, complexed with a Fab fragment and further purified using size-exclusion chromatography. MdfA and MdfA–Fab complexes were subjected to both vapour-diffusion and lipidic cubic phase (LCP) crystallization techniques. Vapour-diffusion-grown crystals were of type II, with poor diffraction behaviour and weak crystal contacts. LCP lipid screening resulted in type I crystals that diffracted to 3.4 Å resolution and belonged to the hexagonal space groupP6122.
Stronger cooling effects of transpiration and leaf physical traits of plants from a hot dry habitat than from a hot wet habitat
Authors: Lin Hua , Chen Yajun , Zhang Houlei , Fu Peili , Fan Zexin
Published: June 2017

Leaf temperature exerts an important impact on the microenvironment and physiological processes of leaves. Plants from different habitats have different strategies to regulate leaf temperature. The relative importance of physical traits and transpiration for leaf temperature regulation in the hot habitat is still unclear.

We investigated 22 leaf physical traits, transpiration, and thermal properties of 38 canopy species of seedlings in a greenhouse, including 18 dominant species from a hot wet habitat (HW) and 20 dominant species from a hot dry habitat (HD). To separate the impact of transpiration and leaf physical traits on leaf temperature, we measured the diurnal courses of leaf temperatures with and without transpiration. The temperature of a reference leaf beside each individual was measured simultaneously to render temperatures comparable.

Generally, the species from HD showed lower leaf temperatures than the species from HW under the same conditions. Both transpiration capacity and cooling effect of leaf physical traits were stronger for the plants from HD. Active transpiration provides a suitable thermal environment for photosynthesis, while xeromorphic leaves can dampen heat stress when transpiration is suppressed. Higher vein density and stomatal pore area index (SPI) facilitated higher transpiration capacity of the plants from HD. Meanwhile, shorter leaves and thinner lower epidermis of the plants from HD were more efficient in heat transfer, although relationships were much weaker than the synergic effect of all the physical traits.

Our results confirmed that transpiration and leaf physical traits provided double insurance for avoiding overheating, particularly for plant from HD. We emphasize that transpiration is a more effective way to cool leaves than physical traits when water is sufficient, which may be an important adaptation for plant from HD where rainfall is sporadic. Our results provide further insight into the relationship between physical traits and transpiration for the regulation of leaf temperature, and the co‐evolution of gas exchange and thermal regulation of leaves.

A plain language summary is available for this article.
Into the storm: Chasing the opportunistic pathogen Staphylococcus aureus from skin colonisation to life‐threatening infections
Authors: O'Gara James P.
Published: June 2017

Colonisation of the human skin by Staphylococcus aureus is a precursor for a variety of infections ranging from boils to sepsis and pneumonia. The rapid emergence of methicillin‐resistant S. aureus following the clinical introduction of this antimicrobial drug and reports of resistance to all currently used anti‐staphylococcal drugs has added to its formidable reputation. S. aureus survival on the skin and in vivo virulence is underpinned by a remarkable environmental adaptability, made possible by highly orchestrated regulation of gene expression and a capacity to undertake genome remodelling. Depending on the ecological or infection niche, controlled expression of a variety of adhesins can be initiated to facilitate adherence to extracellular matrix proteins, survival against desiccation or biofilm accumulation on implanted medical devices and host tissue. These adherence mechanisms complement toxin and enzyme production, immune evasion strategies, and antibiotic resistance and tolerance to collectively thwart efforts to develop reliable antimicrobial drug regimens and an effective S. aureus vaccine.