bluuebunny/crossref_metadata_2025 huggingface dataset:
The changing role of metrics in research institute evaluations undertaken by the Chinese Academy of Sciences (CAS)
Authors: Xu Fang , Li Xiaoxuan
Published: October 2016

As an efficient S&T management tool, the Chinese Academy of Sciences (CAS) institute evaluations have experienced four major systems in which quantitative indicators have played a great role. To better understand the roles of quantitative indicators in CAS institute evaluations and institute development, this article aims to discuss the history and development of the CAS institute evaluation systems. It is concluded that institute evaluation has played a significant role not only in promoting scientific progress but also in guiding the direction and focus of the institutes’ development, thereby aligning it with the CAS’s strategy at different phases. Our intention is that this article offers useful insights for a wide scientific community into CAS’ attitudes on the application of metrics in research institute evaluations. This article is published as part of a collection on the future of research assessment.
Plasma turbulence in the scrape-off layer of the ISTTOK tokamak
Authors: Jorge Rogério , Ricci Paolo , Halpern Federico D. , Loureiro Nuno F. , Silva Carlos
Published: October 2016

The properties of plasma turbulence in a poloidally limited scrape-off layer (SOL) are addressed, with focus on ISTTOK, a large aspect ratio tokamak with a circular cross section. Theoretical investigations based on the drift-reduced Braginskii equations are carried out through linear calculations and non-linear simulations, in two- and three-dimensional geometries. The linear instabilities driving turbulence and the mechanisms that set the amplitude of turbulence as well as the SOL width are identified. A clear asymmetry is shown to exist between the low-field and the high-field sides of the machine. While the comparison between experimental measurements and simulation results shows good agreement in the far SOL, large intermittent events in the near SOL, detected in the experiments, are not captured by the simulations.
A simple model for electron temperature in dilute plasma flows
Authors: Cai Chunpei , Cooke David L.
Published: October 2016

In this short note, we present some work on investigating electron temperatures and potentials in steady dilute plasma flows. The analysis is based on the detailed fluid model for electrons. Ionizations, normalized electron number density gradients, and magnetic fields are neglected. The transport properties are assumed as local constants. With these treatments, the partial differential equation for electron temperature degenerates as an ordinary differential equation. Along an electron streamline, two simple formulas for electron temperature and plasma potential are obtained. These formulas offer some insights, e.g., the electron temperature and plasma potential distributions along an electron streamline include two exponential functions, and the one for plasma potential includes an extra linear distribution function.
Quasi-symmetry and the nature of radial turbulent transport in quasi-poloidal stellarators
Authors: Alcuson J. A. , Reynolds-Barredo J. M. , Bustos A. , Sanchez R. , Tribaldos V. , Xanthopoulos P. , Goerler T. , Newman D. E.
Published: October 2016

Quasi-symmetric configurations have a better neoclassical confinement compared to that of standard stellarators. The reduction of the neoclassical viscosity along the direction of quasi-symmetry should facilitate the self-generation of zonal flows and, consequently, the mitigation of turbulent fluctuations and the ensuing radial transport. Therefore, it is expected that quasi-symmetries should also result in better confinement properties regarding radial turbulent transport. In this paper we show that, at least for quasi-poloidal configurations, the influence of quasi-symmetry on radial transport exceeds the expected reduction of fluctuation levels and associated effective transport coefficients, and that the intimate nature of transport itself is affected. In particular, radial turbulent transport becomes increasingly subdiffusive as the degree of quasi-symmetry becomes larger. This behavior is somewhat reminiscent of what has been previously reported in tokamaks with strong radially sheared zonal flows.
Characterization of laser-cut copper foil X-pinches
Authors: Collins G. W. , Valenzuela J. C. , Hansen S. B. , Wei M. S. , Reed C. T. , Forsman A. C. , Beg F. N.
Published: October 2016

Quantitative data analyses of laser-cut Cu foil X-pinch experiments on the 150 ns quarter-period, ∼250 kA GenASIS driver are presented. Three different foil designs are tested to determine the effects of initial structure on pinch outcome. Foil X-pinch data are also presented alongside the results from wire X-pinches with comparable mass. The X-ray flux and temporal profile of the emission from foil X-pinches differed significantly from that of wire X-pinches, with all emission from the foil X-pinches confined to a ∼3 ns period as opposed to the delayed, long-lasting electron beam emission common in wire X-pinches. Spectroscopic data show K-shell as well as significant L-shell emission from both foil and wire X-pinches. Fits to synthetic spectra using the SCRAM code suggest that pinching foil X's produced a ∼1 keV, ne ≥ 1023 cm−3 plasma. The spectral data combined with the improved reliability of the source timing, flux, and location indicate that foil X-pinches generate a reproducible, K-shell point-projection radiography source that can be easily modified and tailored to suit backlighting needs across a variety of applications.
Larger sized planar wire arrays of complex configuration on 1.5–1.8 MA Z-pinch generator
Authors: Safronova A. S. , Kantsyrev V. L. , Weller M. E. , Shlyaptseva V. V. , Shrestha I. K. , Stafford A. , Schmidt-Petersen M. T. , Lorance M. Y. , Schultz K. A. , Chuvatin A. S.
Published: October 2016

Two new approaches of (i) simultaneous study of implosion and radiative characteristics of different materials in wire array Z-pinch plasmas in one shot and (ii) investigation of larger sized wire arrays (to enhance energy coupling to plasmas and provide better diagnostic access) were developed in experiments with 1.5–1.8 MA Zebra with a Load Current Multiplier. In particular, the larger sized multi-plane Planar Wire Arrays with two outer planes placed at 9 and 15 mm from each other and then as far as at 19 mm (compared with 6 mm studied before at standard 1 MA current) and with a modified central plane with 8 to 12 empty slots were investigated. Though K-shell Al and L-shell Ni, Cu plasmas have similar electron temperatures and densities, the ablation dynamics and radiation of Al and Ni, Cu planes are somewhat different, which was investigated in detail using the full set of diagnostics and modeling. Advantages of using such wire arrays at higher currents to study plasma flow and radiation from different materials and jets are highlighted.
Comparison between experimental Langmuir probes and three species one-dimensional kinetic simulations
Authors: Gonzalez J. , Tierno S. P. , Donoso J. M.
Published: October 2016

The biasing of Langmuir probes to obtain the appropriate measurements in weakly ionized plasmas is addressed in this work. The experimental results show discrepancies when this measurement method is employed with sweep signals of different symmetries or frequencies. This means that the method provides signal dependent plasma parameters, which hinder its diagnosis. In this work, a three species one-dimensional kinetic model is applied with a sweep electric field to simulate the dynamics of a weakly ionized plasma close to a Langmuir probe. With the same symmetries and frequencies for the sweep signal in both the experimental and numerical problems, a qualitative similar behaviour is found. The response of the three species plasma due to changes of the electric field is analysed by means of a three species kinetic collisional model. The effect of constant averaged or energy dependent characteristic collision frequencies is studied. These numerical results are useful to provide a first explanation of the discrepancies found in the experimental data and improve the measurement process.
The nuclear size and mass effects on muonic hydrogen-like atoms embedded in Debye plasma
Authors: Poszwa A. , Bahar M. K. , Soylu A.
Published: October 2016

Effects of finite nuclear size and finite nuclear mass are investigated for muonic atoms and muonic ions embedded in the Debye plasma. Both nuclear charge radii and nuclear masses are taken into account with experimentally determined values. In particular, isotope shifts of bound state energies, radial probability densities, transition energies, and binding energies for several atoms are studied as functions of Debye length. The theoretical model based on semianalytical calculations, the Sturmian expansion method, and the perturbative approach has been constructed, in the nonrelativistic frame. For some limiting cases, the comparison with previous most accurate literature results has been made.
Co-clustering directed graphs to discover asymmetries and directional communities
Authors: Rohe Karl , Qin Tai , Yu Bin
Published: October 2016

Significance

This paper adds to the continuing and long-running interest in networks and network clustering. For directed networks, we propose the
di-sim
algorithm to capture asymmetries of connections and discover directional clusters. We illustrate this algorithm with three data examples: the Enron email network, the hyperlinked blog network during the 2004 US presidential election, and the chemical connections among the neurons in
Caenorhabditis elegans
. We identify informative and bottleneck nodes in all three networks. In particular, for the third example,
di-sim
finds bottleneck nodes that create a feedforward structure among clusters of nodes.
ASBEL
–TCF3 complex is required for the tumorigenicity of colorectal cancer cells
Authors: Taniue Kenzui , Kurimoto Akiko , Takeda Yasuko , Nagashima Takeshi , Okada-Hatakeyama Mariko , Katou Yuki , Shirahige Katsuhiko , Akiyama Tetsu
Published: October 2016

Significance

Wnt/β-catenin signaling plays crucial roles in the regulation of proliferation, cell fate, the self-renewal of stem and progenitor cells, and tumorigenesis. Long noncoding RNAs (lncRNAs), non–protein-coding transcripts longer than 200 nt, also play important roles in a number of biological processes and in tumorigenesis. We show that the lncRNA
ASBEL
[antisense ncRNA in the ANA (Abundant in neuroepithelium area)/BTG3 (B-cell translocation gene 3) locus] and transcription factor 3 (TCF3) are directly transactivated by β-catenin and form a complex that downregulates the expression of activating transcription factor 3 (ATF3). We further demonstrate that
ASBEL
–TCF3–mediated downregulation of ATF3 expression is required for the tumorigenicity of colon cancer cells. Our results suggest that the β-catenin–
ASBEL
–TCF3–ATF3 pathway may be a promising target for colon cancer therapy.
Spatial dynamics of SIRT1 and the subnuclear distribution of NADH species
Authors: Aguilar-Arnal Lorena , Ranjit Suman , Stringari Chiara , Orozco-Solis Ricardo , Gratton Enrico , Sassone-Corsi Paolo
Published: October 2016

Significance

Environmental and nutritional cues are crucial to determine genomic responses. They generally proceed through modulation of epigenetic mechanisms. Nuclear sirtuin 1 (SIRT1) is a well-known epigenetic modifier, because it deacetylates histones, and nutrient sensor, because its enzymatic activity is coupled to hydrolysis of NAD
+
. Compartmentalization of NAD
+
metabolism makes it difficult to predict the pace of NAD
+
-dependent reactions in cells. Here, we use nonlinear optics in live cells to define subnuclear distribution of free and bound NADH, which determines local enzymatic activity. We define subnuclear dynamics of SIRT1 and establish a biophysical signature for SIRT1 activity in live cells. These findings have far-reaching implications, because they describe unique aspects of SIRT1 activity and delineate subnuclear territories of metabolic cues.
Ordinary–extraordinary transition in dynamics of solutions of charged macromolecules
Authors: Muthukumar Murugappan
Published: October 2016

Significance

The experimentally observed phenomenon of the “ordinary–extraordinary” transition from dynamic light-scattering measurements of solutions of charged macromolecules has remained mysterious for the past four decades and has prohibited the use of the Stokes–Einstein law in characterizing the sizes of charged polymers, using light-scattering techniques. The diffusion coefficients of polymers with molecular weight of about 1 million can be merely one-fourth of those of metallic ions such as K
+
, independent of polymer molecular weight and concentration. Similarly charged macromolecules can clump together to make aggregates when electrostatic repulsion between them is dominant and they break apart when the electrostatics are screened. A theory based on counterion dynamics and dipolar interactions is presented in resolving these mysteries.
Structural basis for dynamic regulation of the human 26S proteasome
Authors: Chen Shuobing , Wu Jiayi , Lu Ying , Ma Yong-Bei , Lee Byung-Hoon , Yu Zhou , Ouyang Qi , Finley Daniel J. , Kirschner Marc W. , Mao Youdong
Published: October 2016

Significance

The proteasome holoenzyme is an ATP-dependent protease in eukaryotes that degrades ubiquitylated substrates. It is involved in numerous important biological processes, such as cell division, differentiation, innate immunity, adaptive immunity, regulation of gene expression, and response to proteotoxic stress. Using cryoelectron microscopy, we have examined multiple conformational states of the human proteasome at medium to high resolution. Our results reveal that the substrate-conducting channel in the core particle is transiently opened and accompanied by dynamic changes in structure of the particle. These observations provide new insights into how the proteasome recognizes ubiquitylated substrates and translocates them through a channel and gate to degradation sites in the core particle.
Super-resolution ribosome profiling reveals unannotated translation events inArabidopsis
Authors: Hsu Polly Yingshan , Calviello Lorenzo , Wu Hsin-Yen Larry , Li Fay-Wei , Rothfels Carl J. , Ohler Uwe , Benfey Philip N.
Published: October 2016

Significance

Translation is the process by which ribosomes decode information in RNA to produce proteins. The resulting proteins constitute cellular structures and regulate diverse functions in all organisms. Translation also affects mRNA stability. As the final step of the central dogma, translation can alter protein production more rapidly than transcription in a changing environment. However, a robust experimental method to define the landscape of the translatome has not been established in many organisms. We developed an advanced experimental approach and used it to discover proteins missed in the annotation of theArabidopsisgenome. This study confirmed computationally predicted noncanonical translation events and uncovered unannotated small proteins that likely have important functions in plants.
Modern Value Chains and the Organization of Agrarian Production
Authors: Henderson Heath , Isaac Alan G.
Published: October 2016

Empirical studies of agrarian production in developing countries often find that small farms possess a productivity advantage over larger farms. Eswaran and Kotwal (1986) famously derive this inverse farm‐size/productivity relationship from the structure of agrarian production. The focal prediction of their model is that, in otherwise equivalent economies, a more egalitarian land distribution raises both output and producer welfare. The traditional (spot) procurement system implicit in the Eswaran and Kotwal model, however, diverges fundamentally from modern (contractual) procurement practices. We therefore develop a new model of agrarian production in order to determine whether the introduction of a modern value chain alters the welfare effects of land redistribution. The inverse farm‐size/productivity relationship persists in our model, but we find that more egalitarian land distribution leads to nonmonotonic changes in producer welfare. We also find that the introduction of a modern sector can harm the laboring classes.
Efficiency‐Equity Tradeoffs in Targeting Payments for Ecosystem Services
Authors: Wu JunJie , Yu Jialing
Published: October 2016

This article develops an analytic framework to analyze the tradeoff between economic efficiency and distributional equity in targeting payments for ecosystem services (PES). It also proposes an empirical procedure to trace out the efficiency‐equity frontier, where the program is Pareto optimal in the sense that it cannot be improved upon to achieve either higher efficiency or distributional equity without compromising the other. We apply the procedure to the Conservation Reserve Program (CRP), the largest PES program in U.S. history, to analyze (a) whether it is possible to improve both the efficiency and the distributional equity of the program, and (b) what the choice made by CRP administrators implies about the political‐economic balance. Results reveal that (a) CRP administrators forfeited about 9% of efficiency for an 18%–23% improvement in distributional equity, depending on the equity indicator used, in the eighteenth signup of the CRP; (b) reducing the maximum allowable rental rate for all contracts would improve efficiency at the cost of distributional equity; (c) reducing the maximum county enrollment cap would reduce efficiency without generating much improvement in distributional equity; and (d) the CRP targeting criterion could be redesigned to achieve both higher efficiency and higher distributional equity.
Convergence in leaf size versus twig leaf area scaling: do plants optimize leaf area partitioning?
Authors: Smith Duncan D. , Sperry John S. , Adler Frederick R.
Published: October 2016

Background and Aims Corner’s rule states that thicker twigs bear larger leaves. The exact nature of this relationship and why it should occur has been the subject of numerous studies. It is obvious that thicker twigs should support greater total leaf area (Atwig) for hydraulical and mechanical reasons. But it is not obvious why mean leaf size (A-) should scale positively with Atwig. We asked what this scaling relationship is within species and how variable it is across species. We then developed a model to explain why these relationships exist.

Methods To minimize potential sources of variability, we compared twig properties from six co-occurring and functionally similar species: Acer grandidentatum, Amelanchier alnifolia, Betula occidentalis, Cornus sericea, Populus fremontii and Symphoricarpos oreophilus. We modelled the economics of leaf display, weighing the benefit from light absorption against the cost of leaf tissue, to predict the optimal A- :Atwig combinations under different canopy openings.

Key Results We observed a common A- by Atwig exponent of 0.6, meaning that A -and leaf number on twigs increased in a specific coordination. Common scaling exponents were not supported for relationships between any other measured twig properties. The model consistently predicted positive A- by Atwig scaling when twigs optimally filled canopy openings. The observed 0·6 exponent was predicted when self-shading decreased with larger canopy opening.

Conclusions Our results suggest Corner’s rule may be better understood when recast as positive A- by Atwig scaling. Our model provides a tentative explanation of observed A- by Atwig scaling and suggests different scaling may exist in different environments.
Improving a full-text search engine: the importance of negation detection and family history context to identify cases in a biomedical data warehouse
Authors: Garcelon Nicolas , Neuraz Antoine , Benoit Vincent , Salomon Rémi , Burgun Anita
Published: October 2016

Objective: The repurposing of electronic health records (EHRs) can improve clinical and genetic research for rare diseases. However, significant information in rare disease EHRs is embedded in the narrative reports, which contain many negated clinical signs and family medical history. This paper presents a method to detect family history and negation in narrative reports and evaluates its impact on selecting populations from a clinical data warehouse (CDW).

Materials and Methods: We developed a pipeline to process 1.6 million reports from multiple sources. This pipeline is part of the load process of the Necker Hospital CDW.

Results: We identified patients with “Lupus and diarrhea,” “Crohn’s and diabetes,” and “NPHP1” from the CDW. The overall precision, recall, specificity, and F-measure were 0.85, 0.98, 0.93, and 0.91, respectively.

Conclusion: The proposed method generates a highly accurate identification of cases from a CDW of rare disease EHRs.
The More Stringent, the Better? Rationing Car Use in Bogotá with Moderate and Drastic Restrictions
Authors: Bonilla Jorge A
Published: October 2016

Rationing car use based on license plate number has become a popular policy in several cities around the world to address traffic congestion and air pollution. This paper studies the effects of the moderate and drastic driving restrictions imposed as part of the Pico y Placa program on car use and air pollution in Bogotá. Using data on ambient carbon monoxide, gasoline consumption, and vehicle sales and registrations, no evidence of an improvement in air quality or a reduction in car use is found in either phase of the program. On the contrary, there is some indication that, relative to the moderate phase, gasoline consumption, vehicle ownership, and carbon monoxide in the morning peak tended to increase slightly when drastic restrictions were implemented.
Case-Match Controlled Comparison of Minimally Invasive Plate Osteosynthesis and Intramedullary Nailing for the Stabilization of Humeral Shaft Fractures
Authors: Davies Gareth , Yeo Gerald , Meta Mahendrakumar , Miller David , Hohmann Erik , Tetsworth Kevin
Published: October 2016

Objectives:

To compare the risk of major complications after either minimally invasive plate osteosynthesis (MIPO) or intramedullary nailing (IMN) of humeral shaft fractures.

Design:

Retrospective, case-match controlled study.

Setting:

A major metropolitan tertiary referral trauma center in Australia.

Patients:

Thirty patients with fractures of the humeral shaft.

Intervention:

Either MIPO or IMN were performed on 15 patients each with traumatic humeral shaft fractures.

Primary Outcome Measure:

The cumulative risk of 3 major complications associated with these procedures: nonunion, infection, and iatrogenic radial nerve injury.

Results:

An overall major complication rate of 53% was observed in the patients treated with IMN; one complication (7%) was identified in those managed with humeral MIPO, a nonunion. Complications after IMN included 4 patients (27%) with nonunion, 3 patients (20%) with iatrogenic radial nerve injuries, and 1 patient (7%) with a wound infection. Statistical analysis revealed a significant between-group difference (P = 0.01) in the cumulative rate of major complications. When each of these complications was considered independently, no statistically significant difference was demonstrated.

Conclusions:

This study suggests that humeral MIPO results in a significantly lower pooled major complication rate than that of IMN, and it should therefore be considered an attractive alternative to IMN in those patients requiring surgical stabilization of a traumatic humeral shaft fracture.

Level of Evidence:

Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.
Current Evidence: Plate Versus Intramedullary Nail for Fixation of Distal Tibia Fractures in 2016
Authors: Vallier Heather A.
Published: October 2016

Displaced distal tibia shaft fractures are effectively treated with standard plates and intramedullary nails. Plate fixation performed with meticulous soft tissue handling results in minimal risks of infection and poor wound healing. Standard plates have high rates of primary union, whereas locking plates may delay union because of increased stiffness. Tibial healing may also be delayed after plating of the fibula, although fibula reduction and fixation may aid accuracy of reduction of the tibia. Malalignment occurs more often with infrapatellar intramedullary nailing versus plates, and early results of suprapatellar nailing appear promising in minimizing intraoperative malalignment. Long-term function after fixation of the distal tibia is good for most, with poor outcomes often associated with baseline social and mental health issues.
Tibial Rotation Osteotomies in a Matched Cohort of Myelodysplasia and Cerebral Palsy Children
Authors: Stasikelis Peter J. , Creek Aaron T. , Wack Linda I.
Published: October 2016

Background:

The purpose of this study is to examine the frequency of complications in children with myelodysplasia (MD) undergoing tibial rotational osteotomies with a matched cohort of children with cerebral palsy (CP). It was postulated that because of the unique health issues facing children with MD more complications would be observed.

Methods:

A retrospective chart review was performed to identify children with MD who underwent primary tibial rotational osteotomy between 1997 and 2012 and had a minimum 2-year follow-up. The 15 children thus identified were matched for age, body mass index, and functional ability with 15 children with CP. Outcome measures were complications that occurred within a year of osteotomy or hardware removal. Major complications were defined as nonunions or malunions, hardware failures, deep infections, fractures, and stage III or IV decubiti. Recurrence of rotational deformity requiring revision osteotomy at any time was also defined as a major complication. Minor wound problems healing within 6 weeks with only local care were considered minor complications.

Results:

Fifteen children with MD, who underwent 21 tibial derotational osteotomies, were available for review with a mean 7-year follow-up. The 15 children with CP underwent 22 tibial derotational osteotomies with a mean of 6 years of follow-up. In each cohort there were 3 children classified as GMFCS I, 3 children as GMFCS II, 4 children as GMFCS III, and 5 as GMFCS IV. Three (20%) of the children with MD experienced major complications (1 infected nonunion and 2 children who experienced bilateral malunions requiring revisions). One child with a major complication was classified as GMFCS II and the other 2 as GMFCS IV. None of the children with CP experienced a major complication.

Conclusions:

The majority of children in both groups experienced good results, but children with MD have more frequent major complications. More frequent complications were seen in children with less functional ability.

Level of evidence:

Level III—prognostic study, case-control study.
Fracture Classification Does Not Predict Functional Outcomes in Supracondylar Humerus Fractures: A Prospective Study
Authors: Ernat Justin , Ho Christine , Wimberly Robert L. , Jo ChanHee , Riccio Anthony I.
Published: October 2016

Background:

Few studies have prospectively assessed functional outcomes after the surgical management of supracondylar humerus fractures (SCHFXs) and the relationship between fracture pattern and ultimate patient outcome has never been prospectively evaluated. The purpose of this study was to prospectively evaluate fracture classification and functional outcome in children with extension SCHFXs using validated outcome measures.

Methods:

An Institutional Review Board-approved prospective enrollment of consecutive patients with operative SCHFX was performed over a 3-year period. Fractures were classified by the treating surgeon using the modified Gartland classification. Functional outcome was assessed at final follow-up using the Pediatric Outcomes Data Collection Instruments (PODCI) and the Quick Disabilities of the Arm, Shoulder, and Hand (QuickDASH) outcome measure. Patients with flexion-type fractures, multidirectionally unstable fractures and those with <10 weeks follow-up were excluded from analysis. Statistical analysis was used to determine the relationship between fracture classification/pattern and functional outcome.

Results:

Seven hundred fifty-two patients were enrolled during the study period. One hundred thirty-two patients with extension-type injuries (average age 6.7 y) completed functional outcome measures at an average follow-up of 12.4 weeks. Forty-five (34%) were type II fractures and 87 (66%) were type III fractures. Forty-five (34%) of the fractures were posteromedially displaced, 43 (33%) were posterolaterally displaced, and 44 (33%) were posteriorly displaced without coronal plane deformity. The average PODCI global functioning scale score and QuickDASH scores for the entire cohort were 93.6 and 11.4, respectively, indicating excellent function. No differences in outcome scores were noted between patients with type II and III fractures. No difference in outcome was identified based upon direction of fracture displacement.

Conclusions:

This is the first study to prospectively analyze fracture classification and functional outcome using validated outcome measures following the operative treatment of pediatric extension-type SCHFX. Children generally have excellent functional outcomes following the operative treatment of SCHFX. Garland classification and direction of displacement do not influence functional outcomes.

Level of Evidence:

Level II—therapeutic.
Age-dependent Reliability of Semmes-Weinstein and 2-Point Discrimination Tests in Children
Authors: Dua Karan , Lancaster Timothy P. , Abzug Joshua M.
Published: October 2016

Background:

Objective sensory testing is a critical component of the physical examination in children as they may be unable to communicate whether or not numbness is present. The purpose of this study was to determine at what age objective sensory tests could reliably be performed.

Methods:

Normal, uninjured participants aged 2 to 17 years were enrolled in the study. Monofilament and static/moving 2-point discrimination tests were performed bilaterally assessing the median, ulnar, and radial nerves. Performance scores were recorded using the monofilament size and 2-point discrimination distance. Statistical analysis was performed utilizing univariable linear regression, 1-way ANOVA, and Welch t test.

Results:

A total of 396 hands were tested utilizing the Semmes-Weinstein monofilament and static/moving 2-point discrimination tests. For the monofilament test, 27% of 3-year-olds, 83% of 4-year-olds, and all participants 5 years of age and older were capable of performing the monofilament test. The average monofilament scores were 2.874, 2.868, and 3.043 for the ulnar, median, and radial nerves, respectively, with no correlation with advancing age present. The ulnar and median nerve distributions were more sensitive than the radial nerve distribution (P<0.001).

For 2-point discrimination tests, 33% of 4-year-olds, 61% of 5-year-olds, 88% of 6-year-olds, 95% of 7- and 8-year-olds, and all participants 9 years and older were capable of performing the static/moving 2-point discrimination tests. The average static 2-point discrimination scores were 3.348, 2.806, and 9.637 mm for the ulnar, median, and radial nerves, respectively. The average moving 2-point discrimination scores were 2.977, 2.483, and 8.506 mm for the ulnar, median, and radial nerves, respectively. There was no correlation between advancing age and performance scores. Children are the most sensitive in the median, then ulnar, and then radial nerve distribution (P<0.001). Better discrimination is present between 2 moving points than static points (P<0.001).

Conclusions

Objective threshold testing utilizing a monofilament can reliably be performed in the vast majority of children aged 4 years and above, whereas density testing utilizing 2-point discrimination can reliably be performed in the vast majority of children aged 6 years and above.

Level of Evidence:

Level II.
The Effect of the Pucker Sign on Outcomes of Type III Extension Supracondylar Fractures in Children
Authors: Smuin Dallas M. , Hennrikus William L.
Published: October 2016

Background:

The pucker sign, also called skin tenting, indicates significant displacement of the supracondylar fracture and can be a cause for alarm. The purpose of this study is to compare a cohort of patients with type III supracondylar fractures presenting with a pucker sign to a group without a pucker sign by evaluating neurovascular injury at presentation, need for open reduction, persistent neurovascular injury, range of motion, and carrying angle at final follow-up.

Methods:

A retrospective review was performed for Gartland type III extension type supracondylar fractures. Those with a pucker sign were identified and evaluated. Type III supracondylar fractures with a pucker sign were compared with a similar cohort without a pucker sign.

Results:

In total, 12 patients with a pucker sign at an average age of 5.2 years were evaluated. A total of 11 patients (92%) had diminished or absent pulses, and 2 (17%) had weakness in the median nerve distribution. Nine (75%) patients in this group were transferred to the university hospital. Average time to surgery was 8.9 hours with an average operating time of 25.1 minutes. Open reduction was not needed in any case. At an average follow-up of 4.7 months no patients had persistent neurovascular compromise. Two patients lacked <5 degrees of extension and 1 lacked 10 degrees of extension. One patient lacked 10 degrees of flexion. No patients had a change in carrying angle difference compared with the contralateral side. No statistical differences were observed between the 2 groups.

Conclusions:

Pucker sign, in the context of a supracondylar fracture of the humerus, is a soft tissue defect with potential entrapment of median nerve and brachial artery. At a maximum time of 16 hours from injury to surgery we report excellent outcomes and no long-term complications. Using the techniques of gradual traction, and milking the soft tissue, the pucker sign can be eliminated. Closed reduction and percutaneous pinning were performed in all the cases.

Level of Evidence:

Level III—retrospective comparative study.
The Use of a Simple Dynamic External Fixator for the Treatment of Volar Fracture Subluxation of Proximal Interphalangeal Joints of the Fingers
Authors: Abou Elatta Mohamed M. , Assal Foad , Basheer Hussam M. , Ibrahim Mazen Mohamed
Published: October 2016

Volar fracture dislocation is very uncommon, with few series reported in the literature. Patients with such injuries were treated by modified dynamic external fixators. The mean follow-up was 18 months (range, 6 to 92 mo). The mean range of interphalangeal (proximal interphalangeal) joints and distal interphalangeal joints were 90 and 74 degrees, respectively. The total active range of motion (TAM) was excellent (256 degrees). The mean quick disabilities of the arm, shoulder and hand score was 1.2. The advantages of our external fixators are that they are simple, cheap, adjustable, and allow immediate range of motion.
Arthroscopic-assisted Acromioclavicular and Coracoclavicular Ligaments Reconstruction for Chronic Acromioclavicular Dislocations: Surgical Technique
Authors: Boutsiadis Achilleas , Baverel Laurent , Lenoir Hubert , Delsol Philippe , Barth Johannes
Published: October 2016

Chronic acromioclavicular (AC) instability is a rare posttraumatic shoulder condition that can lead to undesirable symptoms like persistent pain, muscle fatigue, loss of strength, or even scapular dyskinesis. It is well known that in these cases the superior functional results depend on the restoration of the anatomy and stability of the AC joint in both vertical and horizontal planes. Considering the ligaments degeneration and atrophy in chronic AC joint dislocations, we present an arthroscopic-assisted reconstruction of both the coracoclavicular and AC ligaments using autograft augmentation. In details the coracoclavicular ligaments component is reconstructed using the Tightrope suspension device augmented with a palmaris longus autograft and by the nonanatomic coracoacromial ligament transfer (modified Weaver-Dunn). The AC part is restored by suturing the remainder palmaris longus autograft on the acromion and on the deltotrapezial fascia. Using the construct provided by this technique all the possible ruptured ligaments are reconstructed, optimizing the vertical and horizontal stability of the area, and promising excellent long-term radiologic and functional results.
Inhibitor of vasculogenic mimicry restores sensitivity of resistant melanoma cells to DNA-damaging agents
Authors: Vartanian Amalia , Baryshnikova Maria , Burova Olga , Afanasyeva Dariya , Misyurin Vsevolod , Belyаvsky Alexander , Shprakh Zoya
Published: October 2016

The increasing incidence of melanoma makes this cancer an important public health problem. Therapeutic resistance is still a major obstacle to the therapy of patients with metastatic melanomas. The aim of this study was to develop the melanoma cell line resistant to DNA-alkylating agents and to elucidate the mechanisms involved in acquired drug resistance. We established a unique melanoma subline Mel MeR resistant to DNA-alkylating drug aranoza by continuous stepwise selection of the Mel Me/WT cell line with increasing concentrations of this drug. Mel MeR cells were also cross-resistant to streptozotocin or cisplatin. Here, we show that aranoza-resistant melanoma cells modulate the ABC transporter activity, upregulate the expression of PRAME, adopt a vascular-related phenotype and engage in vasculogenic mimicry. LCS1269, a vasculogenic mimicry low-molecular-weight inhibitor, reverses the sensitivity of resistant melanoma cells to DNA-damaging agents. In this study, we provide experimental evidence that LCS1269 might be considered as a new potential anticancer agent capable of overcoming multidrug resistance for DNA-damaging agents in melanoma.
Peripheral neuropathic changes in pachyonychia congenita
Authors: Pan Baohan , Byrnes Kelly , Schwartz Mary , Hansen C. David , Campbell Claudia M. , Krupiczojc Malvina , Caterina Michael J. , Polydefkis Michael
Published: October 2016

We compared patterns of intraepidermal nerve fibers and mechanoreceptors from affected and unaffected plantar skin from patients with pachyonychia congenita (PC) and control subjects. Plantar biopsies from 10 genetically confirmed patients with PC (with a mutation inKRT6A) were performed at the ball of the foot (affected skin) and the arch (unaffected) and were compared to biopsies from corresponding locations in 10 control subjects. Tissue was processed to visualize intraepidermal nerve fibers (IENF) (PGP9.5), subsets of IENF (CGRP, substance P, tyrosine hydroxylase), myelinated nerve fiber (neurofilament H, NFH), blood vessels (CD31), Meissner corpuscles, and Merkel cells (MCs). Structures were quantified using stereology or validated quantification methods. We observed that PC-affected plantar skin had significantly lower sweat gland innervation (sweat gland nerve fiber density) and reduced numbers of Meissner corpuscles compared to PC-unaffected or anatomically matched control skin. In contrast, Merkel cell densities and blood vessel counts were higher in PC-affected skin compared to either control or PC-unaffected skin. There were no differences in myelinated nerve fiber densities, SP, or CGRP between the groups. Pressure pain thresholds in PC-affected skin were lower compared to PC-unaffected and anatomically matched control skin. Additionally, MC densities in callused plantar skin from healthy runners with callus and one subject with a nonpainful palmoplantar keratoderma (AQP5mutation) were similar to PC-unaffected and control skin consistent with callus alone not being sufficient to increase MC number. These findings suggest that alterations in PC extend beyond keratinocytes and may provide strategies to study neuropathic pain in PC.
Manipulating the extracellular matrix: an animal model of the bladder pain syndrome
Authors: Offiah Ifeoma , Didangelos Athanasios , O'Reilly Barry A. , McMahon Stephen B.
Published: October 2016

Bladder pain syndrome (BPS) is associated with breakdown of the protective uroepithelial barrier of the urinary bladder allowing urinary constituents access to bladder sensory neurons. Although there are several animal models of cystitis, none specifically relates to BPS. Here, we aimed to create such a model using enzymatic digestion of the barrier proteoglycans (PGs) in the rat. Twenty female Wistar rats were anaesthetized and transurethrally catheterized. Ten animals were treated with 0.25IU of intravesical chondroitinase ABC and heparanase III to digest chondroitin sulphate and heparin sulphate PGs, respectively. Ten animals received saline. Following PG deglycosylation, bladders showed irregular loss of the apical uroplakin and a significant increase in neutrophils, not evident in the control group. Spinal cord sections were also collected for c-fos analysis. A large and significant increase in fos immunoreactivity in the L6/S1 segments in the treatment vs control bladders was observed. Cystometry was performed on 5 treatment and 5 control animals. Analysis revealed a significant increase in micturition reflex excitability postdeglycosylation. On a further group of 10 animals, von Frey mechanical withdrawal thresholds were tested on abdominal skin before and after PG digestions. There was a significant decrease in abdominal mechanical withdrawal threshold postdeglycosylation compared with controls. The results of this animal study suggest that many of the clinical features of BPS are seen after PG digestion from the bladder lumen. This model can be used to further understand mechanisms of pain in patients with BPS and to test new therapeutic strategies.
Ex vivo nonviral gene delivery of μ-opioid receptor to attenuate cancer-induced pain
Authors: Yamano Seiichi , Viet Chi T. , Dang Dongmin , Dai Jisen , Hanatani Shigeru , Takayama Tadahiro , Kasai Hironori , Imamura Kentaro , Campbell Ron , Ye Yi , Dolan John C. , Kwon William Myung , Schneider Stefan D. , Schmidt Brian L.
Published: October 2016

Virus-mediated gene delivery shows promise for the treatment of chronic pain. However, viral vectors have cytotoxicity. To avoid toxicities and limitations of virus-mediated gene delivery, we developed a novel nonviral hybrid vector: HIV-1 Tat peptide sequence modified with histidine and cysteine residues combined with a cationic lipid. The vector has high transfection efficiency with little cytotoxicity in cancer cell lines including HSC-3 (human tongue squamous cell carcinoma) and exhibits differential expression in HSC-3 (∼45-fold) relative to HGF-1 (human gingival fibroblasts) cells. We used the nonviral vector to transfect cancer with OPRM1, the μ-opioid receptor gene, as a novel method for treating cancer-induced pain. After HSC-3 cells were transfected with OPRM1, a cancer mouse model was created by inoculating the transfected HSC-3 cells into the hind paw or tongue of athymic mice to determine the analgesic potential of OPRM1 transfection. Mice with HSC-3 tumors expressing OPRM1 demonstrated significant antinociception compared with control mice. The effect was reversible with local naloxone administration. We quantified β-endorphin secretion from HSC-3 cells and showed that HSC-3 cells transfected with OPRM1 secreted significantly more β-endorphin than control HSC-3 cells. These findings indicate that nonviral delivery of the OPRM1 gene targeted to the cancer microenvironment has an analgesic effect in a preclinical cancer model, and nonviral gene delivery is a potential treatment for cancer pain.
Morbidly Adherent Placenta
Authors: Baird Suzanne McMurtry , Troiano Nan H. , Kennedy Margaret (Betsy) Babb
Published: October 2016

“Morbidly adherent placenta” is a term that describes the continuum of placenta accreta, increta, and percreta. The incidence of this type of abnormal placentation has increased significantly over recent decades. The reason is probably multifactorial but, partly, because of factors such as the increasing number of cesarean births. Women at greatest risk are those who have myometrial damage caused by a previous cesarean birth, with either anterior or posterior placenta previa overlying the uterine scar. This condition poses significant risks of morbidity and/or mortality to the pregnant woman and her fetus. A multidisciplinary approach to care throughout pregnancy is essential. This article describes the classification of morbidly adherent placenta, risk factors, methods of diagnosis, potential maternal and fetal complications, and intrapartum clinical management strategies to optimize outcomes.
Transition From Hospital to Home in Parents of Preterm Infants
Authors: Boykova Marina
Published: October 2016

Transition from hospital to home is a complex and multidimensional phenomenon for parents of prematurely born infants (<37 weeks of gestation). The absence of a clear conceptualization of this particular transition coupled with the challenges parents have when they return home and higher costs of healthcare service usage postdischarge dictates the need for a better understanding of this phenomenon. A literature review was undertaken using Whittemore and Knafl's theoretical framework for integrative review as a guide. A systematic search of the electronic databases (PsycINFO, PubMed, Medline, Cumulative Index of Nursing and Allied Health Literature, EMBASE, Cochrane Database for Systematic Reviews, and EBSCO) was performed. Fifty selected reports of research conducted on parents of preterm infants during 1980–2014 are included in this article. Five themes emerged from the review—disruption of parental role development, distorted development of parent-infant relationships, psychological consequences of a preterm birth and infant hospitalization, learning caregiving and parenting, and need for social and professional supports—which appear to reflect parental challenges during transition from hospital to home after discharge. Several inconsistencies in results of the studies dictate the need for further research in this vulnerable population; the better conceptualization and measurement of transitional challenges are warranted.
Use of Social Media by Fathers of Premature Infants
Authors: Kim Hyung Nam , Wyatt Tami H. , Li Xueping , Gaylord Mark
Published: October 2016

Although parents of premature infants experience many challenges when transitioning home from the neonatal intensive care unit, healthcare providers and social support systems tend to focus on mothers and infants rather than fathers. Unfortunately, very little is known about paternal concerns and needs as compared with maternal ones. The lack of understanding about paternal needs may lead to inadequate designs of neonatal intensive care unit family support programs with less involved fathers, all of which contribute to increased burdens on mothers and poor health outcomes for their infants. Although information technology (IT) might have the potential to increase support for the fathers of preterm infants, only a few studies have examined systematically how IT applications can be beneficial. This study aims to advance the understanding of needs and concerns of fathers with preterm infants and how fathers use the IT applications (eg, social networking Web sites) to support themselves. We observed qualitatively various social networking Web sites (ie, 29 Web sites) where fathers share their experiences about preterm infants. We discovered that fathers used various social media to discuss their concerns and, in turn, obtained informational, companionship, and emotional supports. On the basis of our analysis, we provide insights into a father-centered technology intervention design.