bluuebunny/crossref_metadata_2025 huggingface dataset:
Novel temperature-controlled RFA probe for treatment of blocked metal biliary stents in patients with pancreaticobiliary cancers: initial experience
Authors: Nayar Manu , Oppong Kofi , Bekkali Noor , Leeds John
Published: April 2018

Background and study aims Radiofrequency ablation (RFA) is used to treat blocked biliary stents in patients with pancreaticobiliary (PB) tumors with varying results. We report our experience with a novel temperature-controlled probe for treatment of blocked metal stents.

Patients and methods Patients with histologically proven PB cancers and a blocked biliary stents were treated using ELRATM electrode (Taewoong Medical) under fluoroscopic guidance. Demographics, clinical outcome, stricture diameter improvements, complications and mortality at 30 days were prospectively recorded.

Results Nine procedures were performed on seven patients (4 male, 3 female); mean age 65.33 (range 56 – 82 years). Mean stricture diameter prior to RFA was 1.13 mm (SD ± 0.54) and 4.42 mm (SD ± 1.54) following RFA (P < 0.0001). Five of seven patients (71 %) required additional stents to ensure optimal drainage. There were no procedure-related complications. Mean follow-up was 193.55 days (range 31 – 540) and three of nine patients (33 %) died due to terminal cancer.

Conclusion These are the first reported data on use of a temperature-controlled RFA catheter in humans to treat blocked metal biliary stents. The device is safe but further randomized trials are required to establish the efficacy and survival benefits of this probe.
Narrow band imaging efficiency in evaluation of mucosal healing/relapse of ulcerative colitis
Authors: Sasanuma Seiko , Ohtsuka Kazuo , Kudo Shin-ei , Ogata Noriyuki , Maeda Yasuharu , Misawa Masashi , Mori Yuichi , Kudo Toyoki , Hisayuki Tomokauzu , Wakamura Kunihiko , Hayashi Takemasa , Katagiri Atsushi , Miyachi Hideyuki , Baba Toshiyuki , Ishida Fumio
Published: April 2018

Background and study aims Mucosal healing is a current treatment target in ulcerative colitis (UC), while histological remission is another target. The aim of this study was to evaluate the efficiency of magnified narrow band imaging (NBI) findings of mucosal healing and their relationship with histological activity and prognosis.

Patients and methods Patients with UC who underwent total colonoscopy between January 2010 and December 2012 with left-sided or total-colitis type UC and achieved clinical remission with an endoscopic Mayo score of 0 or 1 were included. Each colon section was observed with white light and magnified NBI, with the colonoscopy being repeated at 1-year follow-up. We assessed the relationships of magnified NBI with histological disease activity and prognosis. Magnified NBI findings were divided into three categories; honeycomb-like blood vessels (BV-H), blood vessels shaped like bare branches (BV-BB), and blood vessels shaped like vines (BV-V).

Results Fifty-two patients were included. The percentage of remitted mucosa with BV-BB was 37 %, while that of mucosa with scars with BV-H was 35 %. BV-H and BV-BB did not show pathological activity (12/292 and 8/299, respectively), while BV-V showed high pathological activity (27/33, 81 %). There was a correlation between magnified NBI findings and pathological findings (P < 0.01). The odds ratio for inflammation activity at 1-year follow-up was 14.2 for BV-BB (95 % CI, 3.3 – 60.9)

Conclusion Magnified NBI findings showed a good relationship with histological activity. This suggests that we could estimate histological activity without biopsy, and also the possibility of predicting relapse over the following year.
Solution processed ternary blend nano-composite charge regulation layer to enhance inverted OLED performances
Authors: Kaçar Rifat , Mucur Selin Pıravadılı , Yıldız Fikret , Dabak Salih , Tekin Emine
Published: April 2018

Inverted bottom-emission organic light emitting diodes (IBOLEDs) have attracted increasing attention due to their exceptional air stability and applications in active-matrix displays. For gaining high IBOLED device efficiencies, it is crucial to develop an effective strategy to make the bottom electrode easy for charge injection and transport. Charge selectivity, blocking the carrier flow towards the unfavourable side, plays an important role in determining charge carrier balance and accordingly radiative recombination efficiency. It is therefore highly desirable to functionalize an interfacial layer which will perform many different tasks simultaneously. Here, we contribute to the hole-blocking ability of the zinc oxide/polyethyleneimine (ZnO:PEI) nano-composite (NC) interlayer with the intention of increasing the OLED device efficiency. With this purpose in mind, a small amount of 1,3,5-tris(N-phenylbenzimidazol-2-yl)benzene (TPBi) was added as a hole-blocking molecule into the binary blend of ZnO and PEI solution. The device with a ternary ZnO:PEI:TPBi NC interlayer achieved a maximum current efficiency of 38.20 cd A−1 and a power efficiency of 34.29 lm W−1 with a luminance of 123 200 cd m−2, which are high performance parameters for inverted device architecture. The direct comparisons of device performances incorporating ZnO only, ZnO/PEI bilayers, and ZnO:PEI binary NC counterparts were also performed, which shed light on the origin of device performance enhancement.
Effect of externally applied periodic force on ion acoustic waves in superthermal plasmas
Authors: Chowdhury Snigdha , Mandi Laxmikanta , Chatterjee Prasanta
Published: April 2018

Ion acoustic solitary waves in superthermal plasmas are investigated in the presence of trapped electrons. The reductive perturbation technique is employed to obtain a forced Korteweg–de Vries-like Schamel equation. An analytical solution is obtained in the presence of externally applied force. The effect of the external applied periodic force is also observed. The effect of the spectral index (κ), the strength (f0), and the frequency (ω) on the amplitude and width of the solitary wave is obtained. The result may be useful in laboratory plasma as well as space environments.
Contractions from grading
Authors: Krishnan Chethan , Raju Avinash
Published: April 2018

We note that large classes of contractions of algebras that arise in physics can be understood purely algebraically via identifying appropriate Zm-gradings (and their generalizations) on the parent algebra. This includes various types of flat space/Carroll limits of finite and infinite dimensional (A)dS algebras, as well as Galilean and Galilean conformal algebras. Our observations can be regarded as providing a natural context for the Grassmann approach of Krishnan et al. [J. High Energy Phys. 2014(3), 36]. We also introduce a related notion, which we call partial grading, that arises naturally in this context.
An in-depth description of bipolar resistive switching in Cu/HfOx/Pt devices, a 3D kinetic Monte Carlo simulation approach
Authors: Aldana S. , Roldán J. B. , García-Fernández P. , Suñe J. , Romero-Zaliz R. , Jiménez-Molinos F. , Long S. , Gómez-Campos F. , Liu M.
Published: April 2018

A simulation tool based on a 3D kinetic Monte Carlo algorithm has been employed to analyse bipolar conductive bridge RAMs fabricated with Cu/HfOx/Pt stacks. Resistive switching mechanisms are described accounting for the electric field and temperature distributions within the dielectric. The formation and destruction of conductive filaments (CFs) are analysed taking into consideration redox reactions and the joint action of metal ion thermal diffusion and electric field induced drift. Filamentary conduction is considered when different percolation paths are formed in addition to other conventional transport mechanisms in dielectrics. The simulator was tuned by using the experimental data for Cu/HfOx/Pt bipolar devices that were fabricated. Our simulation tool allows for the study of different experimental results, in particular, the current variations due to the electric field changes between the filament tip and the electrode in the High Resistance State. In addition, the density of metallic atoms within the CF can also be characterized along with the corresponding CF resistance description.
MoS2 solid-lubricating film fabricated by atomic layer deposition on Si substrate
Authors: Huang Yazhou , Liu Lei , Lv Jun , Yang Junjie , Sha Jingjie , Chen Yunfei
Published: April 2018

How to reduce friction for improving efficiency in the usage of energy is a constant challenge. Layered material like MoS2 has long been recognized as an effective surface lubricant. Due to low interfacial shear strengths, MoS2 is endowed with nominal frictional coefficient. In this work, MoS2 solid-lubricating film was directly grown by atomic layer deposition (ALD) on Si substrate using MoCl5 and H2S. Various methods were used to observe the grown MoS2 film. Moreover, nanotribological properties of the film were observed by an atomic force microscope (AFM). Results show that MoS2 film can effectively reduce the friction force by about 30-45% under different loads, indicating the huge application value of the film as a solid lubricant. Besides the interlayer-interfaces-sliding, the smaller capillary is another reason why the grown MoS2 film has smaller friction force than that of Si.
A new method for calculating ecological flow: Distribution flow method
Authors: Tan Guangming , Yi Ran , Chang Jianbo , Shu Caiwen , Yin Zhi , Han Shasha , Feng Zhiyong , Lyu Yiwei
Published: April 2018

A distribution flow method (DFM) and its ecological flow index and evaluation grade standard are proposed to study the ecological flow of rivers based on broadening kernel density estimation. The proposed DFM and its ecological flow index and evaluation grade standard are applied into the calculation of ecological flow in the middle reaches of the Yangtze River and compared with traditional calculation method of hydrological ecological flow, method of flow evaluation, and calculation result of fish ecological flow. Results show that the DFM considers the intra- and inter-annual variations in natural runoff, thereby reducing the influence of extreme flow and uneven flow distributions during the year. This method also satisfies the actual runoff demand of river ecosystems, demonstrates superiority over the traditional hydrological methods, and shows a high space–time applicability and application value.
Quadratic electromechanical strain in silicon investigated by scanning probe microscopy
Authors: Yu Junxi , Esfahani Ehsan Nasr , Zhu Qingfeng , Shan Dongliang , Jia Tingting , Xie Shuhong , Li Jiangyu
Published: April 2018

Piezoresponse force microscopy (PFM) is a powerful tool widely used to characterize piezoelectricity and ferroelectricity at the nanoscale. However, it is necessary to distinguish microscopic mechanisms between piezoelectricity and non-piezoelectric contributions measured by PFM. In this work, we systematically investigate the first and second harmonic apparent piezoresponses of a silicon wafer in both vertical and lateral modes, and we show that it exhibits an apparent electromechanical response that is quadratic to the applied electric field, possibly arising from ionic electrochemical dipoles induced by the charged probe. As a result, the electromechanical response measured is dominated by the second harmonic response in the vertical mode, and its polarity can be switched by the DC voltage with the evolving coercive field and maximum amplitude, in sharp contrast to typical ferroelectric materials we used as control. The ionic activity in silicon is also confirmed by the scanning thermo-ionic microscopy measurement, and the work points toward a set of methods to distinguish true piezoelectricity from the apparent ones.
Invisible magnetic sensors
Authors: Mach-Batlle Rosa , Navau Carles , Sanchez Alvaro
Published: April 2018

Sensing magnetic fields is essential in many applications in biomedicine, transportation, or smart cities. The distortion magnetic sensors create in response to the field they are detecting may hinder their use, for example, in applications requiring dense packaging of sensors or accurately shaped field distributions. For sensing electromagnetic waves, cloaking shells that reduce the scattering of sensors have been introduced. However, the problem of making a magnetic sensor undetectable remains unsolved. Here, we present a general strategy on how to make a sensor magnetically invisible while keeping its ability to sense. The sensor is rendered undetectable by surrounding it with a spherical shell having a tailored magnetic permeability. Our method can be applied to arbitrary shaped magnetic sensors in arbitrary magnetic fields. The invisibility can be made exact when the sensor is spherical and the probed field is uniform. A metasurface composed of superconducting pieces is presented as a practical realization of the ideal invisibility shell.
Temperature-dependent spectral linewidths of terahertz Bloch oscillations in biased semiconductor superlattices
Authors: Unuma Takeya , Matsuda Aleph
Published: April 2018

We investigate temperature-dependent spectral linewidths of Bloch oscillations in biased semiconductor superlattices experimentally and theoretically. The spectral linewidth in a GaAs-based superlattice determined by terahertz emission spectroscopy becomes larger gradually as temperature increases from 80 to 320 K. This behavior can be quantitatively reproduced by a microscopic theory of the spectral linewidth that has been extended to treat the phonon scattering and interface roughness scattering of electrons on a Wannier-Stark ladder. A detailed comparison between the terahertz measurements and theoretical simulations reveals that the LO phonon absorption process governs the increase in the spectral linewidth with increasing temperature.
Impact of sire on the lifetime susceptibility of their progeny to breech strike in a Mediterranean environment
Authors: Greeff J. C. , Schlink A. C. , Karlsson L. J. E.
Published: April 2018

The progeny groups of resistant and susceptible sires to breech strike were compared for phenotypic differences in conformation and visual score traits recorded from birth to 5 years of age. The incidences of breech strike in the two most resistant sire progeny groups from birth to hogget shearing were 2.5% and 9.0% respectively, while in the two most susceptible sire progeny groups incidences were 94.5% and 102.9% (some sheep struck more than once) respectively. The susceptible groups consistently had a significantly higher strike rate than did the resistant groups over their lifetime. The adult lifetime breech-strike rates were 0.0% and 27.2% for resistant and susceptible sire groups respectively, despite pre-lambing crutchings. Statistically significant differences existed between the resistant and susceptible sire progeny groups for wrinkle and dags, although, in the present study, the average differences were small (0.2–0.6 unit score) for wrinkle, whereas a difference of 1.2 unit scores was found for yearling dag in spring. The very large differences in breech strike contrasts with the modest differences in the visually detectable breech indicator traits. This suggests that other unknown factors appear to contribute to larger differences than expected in breech strike between the sire progeny groups.
Crossbred ewes gain more weight and are fatter than Merino ewes when managed together but similar coefficients predict lamb birthweight and survival
Authors: Hocking Edwards J. E. , Winslow E. , Behrendt R. , Gordon D. J. , Kearney G. A. , Thompson A. N.
Published: April 2018

Current Australian ewe management guidelines are based on research from Merino ewes and have been transposed to crossbred ewes. It is unknown whether guidelines developed for Merino ewes are applicable to crossbred ewe production systems. To investigate this, the effect of ewe liveweight and condition score profile during pregnancy on lamb birthweight and survival for Border Leicester × Merino (BLM) crossbreds was compared with Merino ewes. Condition score profiles of 720 Merino and 680 BLM ewes were managed from 50 days after ram introduction to achieve one of four target condition scores at lambing. There were three replicates of the four target condition score treatments and both breeds of ewes were in each plot. By Day 140 after rams in, the BLM ewes were fatter (P < 0.001) and heavier (P < 0.001) than the Merino ewes, despite being managed in the same plots. Liveweight at conception and change in liveweight in late pregnancy of the Merino and BLM ewes had a similar effect on the birthweight and weaning weight of their lambs. However, birthweight and weaning weight of lambs from BLM ewes was less sensitive to ewe liveweight change in early pregnancy. Birthweight survival curves were similar in lambs from Merino and multiple-born lambs from BLM ewes, and the survival of lambs from multiple-bearing BLM ewes responded to manipulation of condition score in a similar pattern to lambs from Merino ewes. Therefore, managing liveweight or condition score of multiple-bearing BLM ewes is likely to improve lamb survival in a similar fashion to lambs from Merino ewes, although the absolute response in survival will be smaller than that achieved in Merino ewes at the same condition score. In addition, it is important to manage liveweight of both single and multiple-bearing BLM ewes during pregnancy to optimise weaning weight of their lambs, as those lambs born to BLM ewes of low liveweight were significantly lighter at weaning.
Effects of nutrient supply on carbon and water economies of C4 grasses
Authors: Rose Laura , Buitenwerf Robert , Cramer Michael , February Edmund C. , Higgins Steven I.
Published: April 2018

C3 plants can increase nutrient uptake by increasing transpiration, which promotes the flow of water with dissolved nutrients towards the roots. However, it is not clear if this mechanism of nutrient acquisition, termed ‘mass flow’, also operates in C4 plants. This is an important question, as differences in mass flow capacity may affect competitive interactions between C3 and C4 species. To test if mass flow can be induced in C4 species, we conducted an experiment in a semiarid seasonal savanna in South Africa. We grew six C4 grasses in nutrient-poor sand and supplied no nutrients, nutrients to the roots or nutrients spatially separated from the roots. We measured the rates of photosynthesis and transpiration, water-use efficiency (WUE), nitrogen gain and biomass. For all species biomass, N gain, photosynthesis and transpiration were lowest in the treatment without any nutrient additions. Responses to different nutrient positioning varied among species from no effect on N gain to a 50% reduction when nutrients were spatially separated. The ability to access spatially separated nutrients showed a nonsignificant positive relationship with both the response of transpiration and the response of WUE to spatial nutrient separation. This indicates that nutrient acquisition is not regulated by decreasing WUE in C4 grasses. Overall, our study suggests that under elevated CO2, when evaporative demand is lower, C4 species may be at a competitive disadvantage to C3 species when it comes to nutrient acquisition.
Children’s rights and the non-identity problem
Authors: Magnusson Erik
Published: April 2018

Can appealing to children’s rights help to solve the non-identity problem in cases of procreation? A number of philosophers have answered affirmatively, arguing that even if children cannot be harmed by being born into disadvantaged conditions, they may nevertheless be wronged if those conditions fail to meet a minimal standard of decency to which all children are putatively entitled. This paper defends the tenability of this view by outlining and responding to five prominent objections that have been raised against it in the contemporary literature: (1) the identifiability objection; (2) the non-existence objection; (3) the waiving of rights objection, (4) the lack of legitimate complaint objection; and (5) the unfairness objection.
Weighted Trudinger-Moser inequalities and associated Liouville type equations
Authors: Calanchi Marta , Massa Eugenio , Ruf Bernhard
Published: April 2018

We discuss some Trudinger-Moser inequalities with weighted Sobolev norms. Suitable logarithmic weights in these norms allow an improvement in the maximal growth for integrability when one restricts to radial functions.

The main results concern the application of these inequalities to the existence of solutions for certain mean-field equations of Liouville type. Sharp critical thresholds are found such that for parameters below these thresholds the corresponding functionals are coercive, and hence solutions are obtained as global minima of these functionals. In the critical cases the functionals are no longer coercive and solutions may not exist.

We also discuss a limiting case, in which the allowed growth is of double exponential type. Surprisingly, we are able to show that in this case a local minimum persists to exist for critical and also for slightly supercritical parameters. This allows us to obtain the existence of a second (mountain-pass) solution for almost all slightly supercritical parameters using the Struwe monotonicity trick. This result is in contrast to the non-weighted case, where positive solutions do not exist (in star-shaped domains) in the critical and supercritical cases.
Renal Protective Effects of N-Acetyl-Seryl-Aspartyl-Lysyl-Proline (Ac-SDKP) in Obese Rats on a High-Salt Diet
Authors: Maheshwari Mani , Romero Cesar A , Monu Sumit R , Kumar Nitin , Liao Tang-Dong , Peterson Edward L , Carretero Oscar A
Published: April 2018

BACKGROUND

Obesity is a public health problem, associated with salt sensitive hypertension, kidney inflammation, and fibrosis. N-acetyl-seryl-aspartyl-lysyl-proline (Ac-SDKP) is a tetra peptide with anti-inflammatory and anti-fibrotic properties. However, its effect on preventing kidney damage in obesity is unknown. We hypothesized that Zucker obese (ZO) rats on a high-salt (HS) diet develop renal damage, inflammation, fibrosis, and this is prevented with Ac-SDKP treatment.

METHODS

Zucker lean (ZL) and ZO rats (8 weeks old) were treated with Ac-SDKP (1.6 mg/kg/day) while maintained on either a normal-salt (NS; 0.4%) or HS (4%) diet for 8 weeks. Systolic blood pressure (SBP), albuminuria, renal inflammation, and fibrosis were evaluated.

RESULTS

HS diet increased macrophage infiltration in the kidneys of both ZL and ZO rats but was significantly higher in ZO rats receiving the HS diet (ZL + NS, 13.9 ± 1.3 vs. ZL + HS, 19.14 ± 1.5 and ZO + NS, 25.5 ± 1.4 vs. ZO + HS, 87.8 ± 10.8 cells/mm2; P < 0.05). Ac-SDKP prevented macrophage infiltration in ZO rats (ZO + HS + Ac-SDKP, 32.18 ± 2.4 cells/mm2; P < 0.05). Similarly, glomerulosclerosis, cortical, and medullary interstitial fibrosis were increased in ZO rats fed the HS diet, and Ac-SDKP attenuated these alterations (P < 0.05). SBP was increased in ZO rats fed the HS diet (ZO + NS, 121.3 ± 8.9 vs. ZO + HS, 164 ± 6.9 mm Hg; P < 0.05), and it was significantly decreased with Ac-SDKP treatment (ZO + HS + Ac-SDKP, 144.05 ± 14.1 mm Hg; P = 0.004). Albuminuria was higher in ZO rats than in ZL rats; however, neither HS nor Ac-SDKP treatment affected it.

CONCLUSIONS

Ac-SDKP treatment in ZO rats fed a HS diet prevented renal damage by reducing inflammation, fibrosis, and SBP.
Longitudinal Associations of Neighborhood Crime and Perceived Safety With Blood Pressure: The Multi-Ethnic Study of Atherosclerosis (MESA)
Authors: Mayne Stephanie L , Moore Kari A , Powell-Wiley Tiffany M , Evenson Kelly R , Block Richard , Kershaw Kiarri N
Published: April 2018

BACKGROUND

High neighborhood crime and low perceptions of safety may influence blood pressure (BP) through chronic stress. Few studies have examined these associations using longitudinal data.

METHODS

We used longitudinal data from 528 participants of the Multi-Ethnic Study of Atherosclerosis (aged 45–84, nonhypertensive at baseline) who lived in Chicago, Illinois. We examined associations of changes in individual-level perceived safety, aggregated neighborhood-level perceived safety, and past-year rates of police-recorded crime in a 1, ½, or ¼ mile buffer per 1,000 population with changes in systolic and diastolic BPs using fixed-effects linear regression. BP was measured five times between 2000 and 2012 and was adjusted for antihypertensive medication use (+10 mm Hg added to systolic and +5 mm Hg added to diastolic BP for participants on medication). Models were adjusted for time-varying sociodemographic and health-related characteristics and neighborhood socioeconomic status. We assessed differences by sex.

RESULTS

A standard deviation increase in individual-level perceived safety was associated with a 1.54 mm Hg reduction in systolic BP overall (95% confidence interval [CI]: 0.25, 2.83), and with a 1.24 mm Hg reduction in diastolic BP among women only (95% CI: 0.37, 2.12) in adjusted models. Increased neighborhood-level safety was not associated with BP change. An increase in police-recorded crime was associated with a reduction in systolic and diastolic BPs among women only, but results were sensitive to neighborhood buffer size.

CONCLUSIONS

Results suggest individual perception of neighborhood safety may be particularly salient for systolic BP reduction relative to more objective neighborhood exposures.
Independent Early and Late Sensory Processes for Proprioceptive Integration When Planning a Step
Authors: Saradjian Anahid H , Teasdale Normand , Blouin Jean , Mouchnino Laurence
Published: April 2018

Somatosensory inputs to the cortex undergo an early and a later stage of processing which are characterized by an early and a late somatosensory evoked potentials (SEP). The early response is highly representative of the stimulus characteristics whereas the late response reflects a more integrative, task specific, stage of sensory processing. We hypothesized that the later processing stage is independent of the early processing stage. We tested the prediction that a reduction of the first volley of input to the cortex should not prevent the increase of the late SEP. Using the sensory interference phenomenon, we halved the amplitude of the early response to somatosensory input of the ankle joints (evoked by vibration) when participants either planned a step forward or remained still. Despite the initial cortical response to the vibration being massively decreased in both tasks, the late response was still enhanced during step planning. Source localization indicated the posterior parietal cortex (PPC) as the likely origin of the late response modulation. Overall these results support the dissociation between the processes underlying the early and late SEP. The later processing stage could involve both direct and indirect thalamic connections to PPC which bypass the postcentral somatosensory cortex.
Spatio-temporal aspects of Ca2+ signalling: lessons from guard cells and pollen tubes
Authors: Konrad Kai Robert , Maierhofer Tobias , Hedrich Rainer
Published: April 2018

Changes in cytosolic Ca2+ concentration ([Ca2+]cyt) serve to transmit information in eukaryotic cells. The involvement of this second messenger in plant cell growth as well as osmotic and water relations is well established. After almost 40 years of intense research on the coding and decoding of plant Ca2+ signals, numerous proteins involved in Ca2+ action have been identified. However, we are still far from understanding the complexity of Ca2+ networks. New in vivo Ca2+ imaging techniques combined with molecular genetics allow visualization of spatio-temporal aspects of Ca2+ signalling. In parallel, cell biology together with protein biochemistry and electrophysiology are able to dissect information processing by this second messenger in space and time. Here, we focus on the time-resolved changes in cellular events upon Ca2+ signals, concentrating on the two best-studied cell types, pollen tubes and guard cells. We put their signalling networks side by side, compare them with those of other cell types, and discuss rapid signalling in the context of Ca2+ transients and oscillations to regulate ion homeostasis.
Acute Arthrodesis of Lisfranc Injuries
Authors: Kuhn Kevin , Renninger Christopher , Cochran Grant , Bellamy Joseph
Published: April 2018

The management of acute Lisfranc injuries with tarsometatarsal joint instability has evolved over decades of experience. Arthrodesis historically has been reserved for use as a salvage procedure after development of symptomatic midfoot arthritis or failure of open reduction internal fixation (ORIF) with midfoot collapse; however, recent level I evidence has demonstrated that Lisfranc injuries managed with acute arthrodesis have comparable outcomes when compared with ORIF with less repeat procedures. We describe our technique for surgical management of acute Lisfranc injuries, both high-energy and low-energy variants, with primary arthrodesis. Satisfactory outcomes and complications of this treatment have been shown to be equivocal, if not better, than ORIF for the treatment of acute injuries.

Level of Evidence: Treatment Benefits. Level V. See Instructions for Authors for a complete description of levels of evidence.
Association of BMI and height with the risk of endometrial cancer, overall and by histological subtype: a population-based prospective cohort study in Japan
Authors: Kawachi Asuka , Shimazu Taichi , Budhathoki Sanjeev , Sawada Norie , Yamaji Taiki , Iwasaki Motoki , Inoue Manami , Tsugane Shoichiro
Published: April 2018

Evidence on the association between BMI, height, and endometrial cancer risk, including by subtypes, among Asian populations remains limited. We evaluated the impact of BMI and height on the risk of endometrial cancer, overall and by histological subtype. We prospectively investigated 53 651 Japanese women aged 40–69 years. With an average follow-up duration of 18.6 years, 180 newly diagnosed endometrial cancers were reported, including 119 type 1 and 21 type 2. The association between BMI, height, and endometrial cancer risk was assessed using a Cox proportional hazards regression model with adjustment for potential confounders. Overweight and obesity were associated positively with the risk of endometrial cancer. Compared with BMI of 23.0–24.9 kg/m2, hazard ratios (HRs) (95% confidence intervals) were 1.93 (1.17–3.16) for BMI of 27.0–29.9 kg/m2 and 2.37 (1.20–4.66) for BMI of at least 30.0 kg/m2. On analysis by histological subtype, with each increase in BMI of 5 U, the estimated HR of type 1 endometrial cancer increased (HR=1.54, 95% confidence interval: 1.21–1.98), but HR of type 2 endometrial cancer was unaffected. There was no statistically significant association between height and endometrial cancer risk. In conclusion, the risk of endometrial cancer was elevated in women with a BMI of at least 27.0 kg/m2. By histological subtype, BMI was associated with type 1, but not type 2 endometrial cancer risk among a population with a relatively low BMI compared with western populations.
Mohs Micrographic Surgery Volume and Payment Patterns Among Dermatologists in the Medicare Population, 2013
Authors: Johnstone Cameron , Joiner Keith A. , Pierce John , Krouse Robert S.
Published: April 2018

Objectives:

Mohs micrographic surgery (MMS) has expanded markedly in recent years but there is limited information on volume, practice patterns or reimbursement. This study characterizes MMS utilization in the Medicare population.

Materials and Methods:

We analyzed the Medicare Provider Utilization and Payment Data: Physician and Other Supplier Public Use File Calendar Year 2013 data set for provider service volume and reimbursement for dermatologists who did and did not perform MMS procedures.

Results:

Total Medicare-funded MMS procedures increased 25% from 2009 (558,447) to 2013 (700,262). Dermatologists who performed MMS had significantly more average services per provider (5419.4 vs. 3627.1, r=0.16, P<0.0001), were reimbursed significantly more in average total procedure-related compensation ($475,883.64 vs. $144,564.74, r=0.49, P<0.0001) than dermatologists who did not perform MMS, and made up 71.3% of the top decile of dermatologists ranked by total reimbursement received from Medicare. Total MMS service volume and reimbursement was concentrated among a subset of providers. Among MMS providers, a higher volume of MMS procedures was correlated with a greater likelihood of performing procedures on lesions located on the trunk, arms or legs (r=0.27, P<0.001).

Conclusions:

In 2013 reimbursement for MMS comprised almost 19% of the amount reimbursed by Medicare Part B Fee For Service to dermatologists and greater than half a percent of the total amount reimbursed to all physicians participating in the program. Further studies incorporating clinical and outcomes data are needed to evaluate appropriate utilization of this procedure.
Oncocytic Metaplasia in Melanocytic Tumors
Authors: Ahn Christine , DeSantis Emily , McCalmont Timothy
Published: April 2018

Oncocytic metaplasia represents a histopathologic feature that can be observed in normal tissue such as salivary and lacrimal glands but may also constitute a degenerative metaplastic process as a result of repeated oxidative damage during cellular aging. Although cutaneous oncocytic metaplasia has been considered rare, the finding was seen in over one-third of melanocytic nevi prospectively evaluated, in one study. This case series reports on a small series of oncocytic melanocytic tumors, with the aim of describing this phenomenon in varied contexts and also describing the use of a mitochondrial antigen immunostain, which has not been previously reported.
Alterations of Inflammatory and Matrix Production Indices in Celiac Disease With Low Bone Mass on Long-term Gluten-free Diet
Authors: Di Stefano Michele , Bergonzi Manuela , Benedetti Irene , De Amici Mara , Torre Cristina , Brondino Natascia , Miceli Emanuela , Pagani Elisabetta , Marseglia Gian L. , Corazza Gino R. , Di Sabatino Antonio
Published: April 2018

Background:

A clinically meaningful impairment of bone mass secondary to malabsorption is frequent in untreated celiac disease. In adult patients, a rigorous gluten-free diet (GFD) significantly improves, but does not always normalize, bone mineral density (BMD). The reason for this marginal response is unclear. Accordingly, we evaluated the role of both local and systemic factors for bone loss in celiac patients on long-term GFD.

Study:

In a prospective cohort, 22 patients with low lumbar and/or femoral BMD and 22 with normal BMD underwent bone and mineral metabolism evaluation: we tested calcium, phosphate, parathyroid hormone, and vitamin D; telopeptide of type I collagen, a bone resorption index; propeptide of type I procollagen, a bone neoformation index; receptor antagonist of NF-kB ligand, an osteoclast-stimulating factor; osteoprotegerin (OPG), a decoy receptor for RANKL. Sunlight exposure and physical exercise were measured.

Results:

Patients with bone loss showed prevalently osteopenia, severe osteoporosis was rare. In comparison with normal BMD patients, they showed higher serum OPG, telopeptide, and lower serum propeptide, suggesting an increased bone turnover. Lumbar T-score was negatively correlated with OPG, telopeptide and RANKL and positively with propeptide. Propeptide was negatively correlated with OPG and telopeptide. OPG was positively correlated with telopeptide.

Conclusions:

The persistent activation of inflammation should be considered the main pathophysiological mechanism for bone defect in celiac disease patients with bone loss on long-term GFD. High levels of OPG, an attempt at protective mechanism, and low levels of propeptide of type I procollagen, reflecting an insufficient matrix production, characterize this subgroup of patients.
An Altered Eating Experience: Attitudes Toward Feeding Assistance Among Younger and Older Adults
Authors: Shune Samantha E.
Published: April 2018

Purpose

Feeding assistance is commonly used to alleviate mealtime difficulties and decrease risk. It is unclear how to best support the transition from independence to assisted feeding across the lifespan. The purpose of this exploratory study was to examine attitudes toward feeding assistance among healthy younger and older adults.

Design

Qualitative study.

Methods

A total of 17 younger and 19 older adults were interviewed following a simulated feeding (assisted and self-feeding) experience. Comments were coded for sensation (physical/emotional) and sentiment (positive/negative/neutral) and analyzed for common themes.

Findings

All participants commented primarily on the physical aspects of feeding assistance. Younger adults were more likely than older adults to make negative comments, particularly as related to the loss of independence. All participants indicated difficulties/differences with the feeding process stemming from their own preferences not being realized.

Conclusions/Clinical Relevance

Although all adults value independence in the aging process, younger adults may more negatively view receiving feeding assistance as a loss of independence. This suggests the need to redefine autonomy in the presence of increased dependence. It is also necessary to individualize the feeding process in order to incorporate individual identity into eating. Promoting interdependence as the consequence of feeding assistance, rather than dependence, can help support this time of transition and promote patient well-being.
Necrotizing Soft Tissue Infection: Diagnostic Accuracy of Physical Examination, Imaging, and LRINEC Score
Authors: Fernando Shannon M. , Tran Alexandre , Cheng Wei , Rochwerg Bram , Kyeremanteng Kwadwo , Seely Andrew J. E. , Inaba Kenji , Perry Jeffrey J.
Published: April 2018

Objective:

We sought to summarize accuracy of physical examination, imaging, and Laboratory Risk Indicator for Necrotizing Fasciitis (LRINEC) score in diagnosis of necrotizing soft tissue infection (NSTI) in adults with a soft tissue infection clinically concerning for NSTI.

Summary of Background Data:

NSTI is a life-threatening diagnosis. Delay to diagnosis and surgical management is associated with increased mortality.

Methods:

We searched 6 databases from inception through November 2017. We included English-language studies reporting diagnostic accuracy of testing or LRINEC Score. Outcome was NSTI confirmed by surgery or histopathology. Two reviewers screened all citations and extracted data independently. Summary measures were obtained from the Hierarchical Summary Receiver Operating Characteristic model.

Results:

From 2,290 citations, we included 23 studies (n = 5982). Of physical examination signs, pooled sensitivity and specificity for fever was 46.0% and 77.0% respectively, for hemorrhagic bullae 25.2% and 95.8%, and for hypotension 21.0% and 97.7%. Computed tomography (CT) had sensitivity of 88.5% and specificity of 93.3%, while plain radiography had sensitivity of 48.9% and specificity of 94.0%. Finally, LRINEC ≥ 6 had sensitivity of 68.2% and specificity of 84.8%, while LRINEC ≥ 8 had sensitivity of 40.8% and specificity of 94.9%.

Conclusions:

Absence of any 1 physical examination feature (eg, fever or hypotension) is not sufficient to rule-out NSTI. CT is superior to plain radiography. LRINEC had poor sensitivity, and should not be used to rule-out NSTI. Given the poor sensitivity of these tests, a high clinical suspicion warrants early surgical consultation for definitive diagnosis and management.
Number of Examined Lymph Nodes and Nodal Status Assessment in Distal Pancreatectomy for Body/Tail Ductal Adenocarcinoma
Authors: Malleo Giuseppe , Maggino Laura , Ferrone Cristina R. , Marchegiani Giovanni , Mino-Kenudson Mari , Capelli Paola , Rusev Borislav , Lillemoe Keith D. , Bassi Claudio , Fernàndez-del Castillo Carlos , Salvia Roberto
Published: April 2018

Objective:

First, to assess the impact of the number of examined lymph nodes (ELNs) on staging and survival after distal pancreatectomy (DP) for pancreatic adenocarcinoma (PDAC). Second, to identify the minimum number of ELNs (MNELNs) ensuring an accurate detection of nodal involvement. Third, to reappraise the role of lymph node (LN) parameters, including N-status and lymph node ratio (LNR).

Background:

In contrast with pancreatoduodenectomy, information on LN staging and the MNELN required in DP is lacking.

Methods:

Patients undergoing DP for PDAC at 2 academic hospitals from 2000 through 2013 were retrospectively analyzed. The eighth edition of the American Joint Committee on Cancer staging system was used. The MNELN was estimated using the binomial probability law. Survival analyses were performed separately for node-negative and node-positive patients using univariable and multivariable models.

Results:

The study population consisted of 240 patients. The median number of ELN was 21, significantly lower in node-negative patients as compared with node-positive patients (18.5 vs 24.0; P = 0.001). The proportion of node-positive patients increased with increasing numbers of ELNs, whereas LNR showed an inverse trend. The estimated MNELN was 20. The number of ELN (≥ or <20) was an independent prognostic factor only in node-negative patients [odds ratio (OR) 3.23 for ELN <20), suggesting a stage migration effect. In node-positive patients, N2-class, but not LNR, was a significant predictor of survival at multivariable analysis (OR 1.68).

Conclusion:

The number of ELN affects nodal staging in body/tail PDAC. At least 20 LNs are required for correct staging. N-status is superior to LNR in predicting survival of node-positive patients.
Preoperative Predictive Factors of Conversions in Laparoscopic Splenectomies
Authors: Vecchio Rosario , Milluzzo Sebastian M. , Troina Graziano , Cacciola Emma , Cacciola Rossella R. , Catalano Renato S. , Caputo Marco
Published: April 2018

Purpose:

Presently, laparoscopic splenectomy (LS) is being performed for several indications in clinical practice. However, conversion to open surgery is occasionally required in some patients. We analyzed the intraoperative indications and potential preoperative predictors associated with conversion to open surgery in those presenting for LS.

Methods:

We reviewed 107 patients who underwent LS. We analyzed the surgical indications, spleen size, surgical procedure performed, operative time, rate of and indications for conversions, as well as postoperative complications.

Results:

Among the 15 patients (14.0%) who underwent conversion, the conversion was related to the occurrence of a splenic lymphoma in 10, severe bleeding in 3, a lack of anatomic definition in 1, and splenic candidiasis in 1 patient. A comparison between the results obtained in the initial 30 patients (LS performed during the learning curve) and those obtained in the remaining 77 patients, showed that conversions appeared to be related to the experience/expertise of the surgical team excluding patients with splenic malignancies. Conversion was not associated with a higher morbidity-mortality rate, but only a longer length of hospitalization.

Conclusions:

LS is a gold standard procedure when performed by experienced and competent surgeons. However, careful patient selection is recommended before using the laparoscopic approach in those presenting with splenic malignancies.
Differential arthropod responses to warming are altering the structure of Arctic communities
Authors: Koltz Amanda M. , Schmidt Niels M. , Høye Toke T.
Published: April 2018

The Arctic is experiencing some of the fastest rates of warming on the planet. Although many studies have documented responses to such warming by individual species, the idiosyncratic nature of these findings has prevented us from extrapolating them to community-level predictions. Here, we leverage the availability of a long-term dataset from Zackenberg, Greenland (593 700 specimens collected between 1996 and 2014), to investigate how climate parameters influence the abundance of different arthropod groups and overall community composition. We find that variation in mean seasonal temperatures, winter duration and winter freeze–thaw events is correlated with taxon-specific and habitat-dependent changes in arthropod abundances. In addition, we find that arthropod communities have exhibited compositional changes consistent with the expected effects of recent shifts towards warmer active seasons and fewer freeze–thaw events in NE Greenland. Changes in community composition are up to five times more extreme in drier than wet habitats, with herbivores and parasitoids generally increasing in abundance, while the opposite is true for surface detritivores. These results suggest that species interactions and food web dynamics are changing in the Arctic, with potential implications for key ecosystem processes such as decomposition, nutrient cycling and primary productivity.
Determination of cyanide in bamboo shoots by microdiffusion combined with ion chromatography–pulsed amperometric detection
Authors: Ding Ming , Wang Kailiang
Published: April 2018

A practical method for the determination of cyanide in bamboo shoots has been developed using microdiffusion preparation integrated with ion chromatography–pulsed amperometric detection (IC-PAD). Cyanide was released from bamboo shoots after Conway cell microdiffusion, and then analysed by IC-PAD. In comparison with the previously reported methods, derivatization and ion-pairing agent addition were not required in this proposed microdiffusion combined with IC-PAD method. The microdiffusion parameters were optimized including hydrolysis systems, temperature, time, and so on. Under the optimum conditions, the linear range of the calibration curve for cyanide was 0.2–200.0 µg kg
−1
with satisfactory correlation coefficients of 0.9996 and the limit of detection was 0.2 µg kg
−1
(
S/N
 = 3). The spiked recovery range was from 92.8 to 98.6%. The intra-day and inter-day relative standard deviations of cyanide were 2.7–14.9% and 3.0–18.3%, respectively. This method was proved to be convenient in operation with high sensitivity, precision and accuracy, and was successfully applied in the determination of cyanide in bamboo shoot samples.
Straightforward and precise approach to replicate complex hierarchical structures from plant surfaces onto soft matter polymer
Authors: Kumar Charchit , Le Houérou Vincent , Speck Thomas , Bohn Holger F.
Published: April 2018

The surfaces of plant leaves are rarely smooth and often possess a species-specific micro- and/or nano-structuring. These structures usually influence the surface functionality of the leaves such as wettability, optical properties, friction and adhesion in insect–plant interactions. This work presents a simple, convenient, inexpensive and precise two-step micro-replication technique to transfer surface microstructures of plant leaves onto highly transparent soft polymer material. Leaves of three different plants with variable size (0.5–100 µm), shape and complexity (hierarchical levels) of their surface microstructures were selected as model bio-templates. A thermoset epoxy resin was used at ambient conditions to produce negative moulds directly from fresh plant leaves. An alkaline chemical treatment was established to remove the entirety of the leaf material from the cured negative epoxy mould when necessary, i.e. for highly complex hierarchical structures. Obtained moulds were filled up afterwards with low viscosity silicone elastomer (PDMS) to obtain positive surface replicas. Comparative scanning electron microscopy investigations (original plant leaves and replicated polymeric surfaces) reveal the high precision and versatility of this replication technique. This technique has promising future application for the development of bioinspired functional surfaces. Additionally, the fabricated polymer replicas provide a model to systematically investigate the structural key points of surface functionalities.