bluuebunny/crossref_metadata_2025 huggingface dataset:
Highly accurate simplified lattice Boltzmann method
Authors: Chen Z. , Shu C. , Tan D.
Published: October 2018

In this paper, we present a highly accurate simplified lattice Boltzmann method (HSLBM) which can achieve the third-order of accuracy in space. By introducing virtual streaming nodes and decoupling the streaming distance from the mesh spacing, HSLBM effectively combines the local second-order simplified and highly stable lattice Boltzmann method (SHSLBM) and the overall high order scheme. The correlation between the streaming distance and the mesh spacing is accomplished by a high-order Lagrange interpolation algorithm. Through a series of tests, it is found that using 5 interpolation points and setting streaming distance as 1/5 of the mesh spacing can give optimal results. In general, HSLBM improves the accuracy of SHSLBM from the second order to the third order, while maintaining its merits like low memory cost, convenient implementation of physical boundary conditions, and good numerical stability. To match the accuracy of the flow solver, a linear extrapolation scheme with the third-order of accuracy is also proposed to determine the boundary values of the non-equilibrium distribution functions. Various benchmark tests are performed to demonstrate the robustness of HSLBM in simulating two- and three-dimensional incompressible viscous flows as well as its flexibility in problems with curved boundaries and on body-fitted meshes.
End loss for Stokes flow through a slippery circular pore in a barrier of finite thickness
Authors: Ng Chiu-On , Xie Wenxiong
Published: October 2018

An analytical model based on the fluid cylinder approximation and eigenfunction expansions is developed for Stokes flow through a slippery circular pore in a barrier of finite thickness. The hydraulic resistance, which comprises the end resistance and Poiseuille resistance, is determined as a function of the pore thickness, slip length of the pore wall, and proximity of pores. The results are presented to reveal how wall slip may change, quantitatively and qualitatively, the effect of the pore thickness on the end resistance. It is shown, in particular, that the use of Sampson’s formula may underestimate the end loss under the effect of wall slip. Velocity slip on the wall will cause a greater departure of the velocity profile at the inlet from that of the fully developed flow, and therefore, a longer entrance length is required for the flow to attain its final state. Empirical formulas are proposed to facilitate quick calculation of the end resistance as a function of the controlling parameters.
Experimental studies on radio frequency sources for ionospheric heaters
Authors: Beaudoin Brian L. , Ting Antonio , Gold Steven , Narayan Amith H. , Fischer Richard , Karakkad Jayakrishnan A. , Nusinovich Gregory S. , Antonsen Thomas M.
Published: October 2018

The ionosphere plays a prominent role in the performance of critical civilian and military communication systems. The properties of the ionosphere can be affected by Ionospheric Modification (IM). The key instrument in IM research is a powerful, ground-based, high frequency source of electromagnetic waves known as a heater. Existing heaters operate with large, fixed location antenna arrays. With a mobile heater, investigators would be able to conduct IM research at different latitudes without building a costly permanent installation. For developing a mobile heater with a much smaller antenna array, a new highly efficient megawatt-class Radio Frequency (RF) source is required to reduce the overall power demands on a fully deployable system. The concept of such a source has been described previously [Beaudoin et al., J. Electromagn. Waves Appl. 31(17), 1786–1801 (2017)]. Here, experimental results using an electron beam produced by a gridded thermionic electron gun to drive an external lumped element circuit for a high efficiency RF generation are reported. The gun produces an electron beam bunched at the driving frequency with a narrow phase angle spread that is then collected by an external circuit for resonant impedance matching to the load. The results showed that effects, such as the internal resistance of the inductor and deflection of the beam electrons by the induced RF voltages on the beam collector, are important considerations to be included in the design of a practical device using this configuration for high efficiency RF generation.
Biofuel ash addition increases ectomycorrhizal fungal exudation in pure culture
Authors: Vilches Ana Paola , Norström Sara H. , Olofsson Madelen A. , Fransson Petra , Bylund Dan
Published: October 2018

Environmental contextSpreading recycled wood ash in forests may counteract acidification and nutrient losses, but the process may also affect symbiotic fungi in these eco-systems. We show how fungal species react when exposed to ash solutions; for example, by an increased release of organic acids and other compounds. These effects can influence pH and metal availability in forest soils treated with ash. AbstractRecycling of wood ash may counteract acidification and losses of base cations resulting from whole-tree harvesting in boreal forest ecosystems. The effects of ash treatment on growth and exudation of eight ectomycorrhizal fungal species were investigated in this study. Six basidiomycetes and two ascomycetes were grown in liquid pure culture with different levels of ash amendments. Biomass production, pH and the exudation of 17 low-molecular-mass organic acids (LMMOAs), 23 amino acids (AAs) and 9 hydroxamate siderophores (HSs) were recorded after 1, 2 and 4 weeks of incubation. Ash did not affect fungal growth, but resulted in higher exudation of the investigated compounds, in particular LMMOAs. Ash also influenced the composition of the exudates. We measured exudation of LMMOAs and AAs up to millimolar and micromolar concentrations respectively. For example, Rhizopogon roseolus mainly produced oxalic acid, whereas Lactarius rufus and Tomentellopsis submollis produced the highest concentrations of AAs. Ferricrocin, the only HS detected, was exuded at the nanomolar level. Exudation responses were also highly species-dependent, e.g. the ascomycetous isolates that produced the largest biomass released low amounts of exudates compared with the basidiomycetes, and were the only ones producing siderophores. This growth–exudation response to ash is likely a trade-off in carbon allocation whereby the mycorrhizal fungal species invest carbon in either higher biomass production or higher exudation.
Oocyte-specific ablation of N- and O-glycans alters cumulus cell signalling and extracellular matrix composition
Authors: Lo Belinda K. M. , Archibong-Omon Agnes , Ploutarchou Panayiota , Day Anthony J. , Milner Caroline M. , Williams Suzannah A.
Published: October 2018

Cumulus–oocyte complex (COC) expansion is essential for ovulation and fertilisation and is linked to oocyte quality. Hyaluronan (HA), the major matrix constituent, is cross-linked via inter-α-inhibitor heavy chains (HCs), pentraxin 3 (PTX3) and tumour necrosis factor-stimulated gene 6 (TSG-6). All except HCs are secreted by cumulus cells in response to oocyte-secreted factors, which signal via SMAD pathways. The double mutant (DM) mouse generates oocytes lacking complex N- and O-glycans due to oocyte-specific deletion of core 1 β1,3-galactosyltransferase (C1galt1) and N-acetylglucosaminyltransferase I (Mgat1) and has modified cumulus expansion. We compared COCs before expansion (48 h-post-pregnant mare serum gonadotrophin (PMSG)) and at late-stage expansion (9 h-post-human chorionic gonadotrophin (hCG); control n=3 mice, DM n=3 per group). Using histochemistry the levels of HA, HCs, PTX3, TSG-6 and phosphorylated-SMAD1/5/8 and -SMAD2 (12–25 COCs per group) were assessed. DM COCs did not differ from Controls in cumulus size or cell density at 9 h-post-hCG; however, HA and HC levels and phosphorylated-SMAD1/5/8 were reduced. Furthermore, no correlations were found between the levels of matrix molecules and cumulus area in DM or Control samples. These data suggest that HA and HCs can support cumulus expansion provided that they are present above minimum threshold levels. We propose that oocyte-specific ablation of C1galt1 and Mgat1 may affect bone morphogenetic protein 15 synthesis or bioactivity, thereby reducing SMAD1/5/8 phosphorylation and HA production.
Bifunctional amyloid-reactive peptide promotes binding of antibody 11-1F4 to diverse amyloid types and enhances therapeutic efficacy
Authors: Wall Jonathan S. , Williams Angela D. , Foster James S. , Richey Tina , Stuckey Alan , Macy Sallie , Wooliver Craig , Campagna Shawn R. , Tague Eric D. , Farmer Abigail T. , Lands Ronald H. , Martin Emily B. , Heidel R. Eric , Kennel Stephen J.
Published: October 2018

Significance

Amyloidosis is characterized by the deposition of pathologic protein fibrils in organs and tissues and is associated with ∼25 disorders, including Alzheimer’s disease and a systemic disease resulting from the aggregation of immunoglobulin light chains. Present treatments focus on reducing production of amyloid precursor proteins, but recent studies using amyloid-reactive antibodies have shown them capable of removing amyloid and improving organ function. To expand the utility of one such clinical antibody, designated 11-1F4, we have developed a synthetic, bifunctional peptide that binds many types of amyloid and mediates the recruitment of antibody to diverse amyloid types. This peptide approach may be used to enhance the efficacy and utility of existing antibodies, leading to broad-spectrum therapeutics and improved patient care.
Soft conductive micropillar electrode arrays for biologically relevant electrophysiological recording
Authors: Liu Yuxin , McGuire Allister F. , Lou Hsin-Ya , Li Thomas L. , Tok Jeffrey B.-H. , Cui Bianxiao , Bao Zhenan
Published: October 2018

Significance

The large mechanical discrepancy at the cell–electrode interface (∼6 orders of magnitude difference in Young’s moduli) is known to significantly affect the cell’s behavior and its mechanotransduction pathways. To date, the Young’s moduli of the electrode materials do not match those of the cells, due to the limited availability of required electronic materials for microfabrication. Here, we present a soft micropillar electrode array made of electronically conductive hydrogel as a general tool for electrophysiological recording. The three-dimensional microelectrode provides biologically relevant mechanical microenvironment to the cells during electrophysiological recording with higher amplitude and signal-to-noise ratio compared with a state-of-the-art inorganic microelectrode.
BRI1 controls vascular cell fate in the
Arabidopsis
root through RLP44 and phytosulfokine signaling
Authors: Holzwart Eleonore , Huerta Apolonio Ignacio , Glöckner Nina , Garnelo Gómez Borja , Wanke Friederike , Augustin Sebastian , Askani Jana Christin , Schürholz Ann-Kathrin , Harter Klaus , Wolf Sebastian
Published: October 2018

Significance

Cell-fate determination and cellular behavior in plants rely mainly on positional information and intercellular communication. A plethora of cues are perceived by surface receptors and integrated into an adequate cellular output. Here, we show that the small receptor-like protein RLP44 acts as an intermediary to connect the receptors for two well-known signaling molecules, brassinosteroid and phytosulfokine, to control cell fate in the root vasculature. Furthermore, we show that the brassinosteroid receptor has functions that are independent from the responses to its hormone ligands and reveal that phytosulfokine signaling promotes procambial cell identity. These results provide a mechanistic framework for the integration of multiple signaling pathways at the plasma membrane by shifting associations of receptors in multiprotein complexes.
Representativeness of Patients Enrolled in a Primary Care Clinical Trial for Heavy/Problem Substance Use
Authors: Kelpin Sydney S. , Ondersma Steven J. , Weaver Michael , Svikis Dace S.
Published: October 2018

Background: The extent to which participants in randomized clinical trials (RCTs) resemble their broader target groups is of particular concern when studying stigmatized conditions such as substance use disorders (SUDs). The present study compared patients who enrolled in a 4-arm clinical trial of SBIRT (screening, brief intervention, and referral to treatment) with eligible patients who declined study participation. Methods: Participants ( N = 1338) were primary care patients who anonymously completed a computer-delivered health survey and screened positive for heavy/problem alcohol or drug use. Those who consented to the RCT ( n = 713) were compared with those who declined ( n = 625) on a variety of demographic, substance use, and psychosocial characteristics. Variables significant at P < .20 in univariate analyses were then examined using multivariate logistic regression to determine their combined effect. Results: The sample was 60% female and 76% African American, with a mean age of 45.2 years. Patients who consented to participate differed from those who declined on 34 (60%) of the 57 variables studied. The most parsimonious model by multivariate regression found that those who consented were older, more likely to be unemployed, and more likely to endorse prescription drug misuse, problems related to drug use, family history of alcohol problems, trouble falling asleep, and a health professional recommendation to lose weight. Conclusion: Patients consenting to the RCT reported a greater number and more severe psychosocial and mental health problems than those who declined study participation. If the higher level of risk among study participants was found in other studies as well, it would raise questions regarding the generalizability of RCT results to broader clinic samples.
Relative impacts of mild and major neurocognitive disorder on rate of verbal learning acquisition
Authors: Webber Troy A , Marceaux Janice C , Critchfield Edan A , Soble Jason R
Published: October 2018

Objective

The California Verbal Learning Test—second edition (CVLT-II) learning slope index may signal the presence of cognitive impairment, though the relative impacts of mild (MiND) and major (MaND) neurocognitive disorders on the rate of verbal learning acquisition remain unknown.

Methods

Latent intercept-only, linear, quadratic, and exponential models were fit to raw scores for the five CVLT-II learning trials of 197 veterans. Dummy-coded variables reflecting MiND and MaND predicted the growth factors.

Results

Quadratic growth best fit the data. MiND and MaND predicted reduced recall on each trial. MaND predicted reduced rate of learning acquisition (i.e., word gains per trial) over-and-above MiND, even after controlling for age, sex, education, race/ethnicity, and mono/bilingualism.

Conclusions

Nonlinear growth—with continuous but diminishing gains over trials—best characterized verbal learning acquisition. Reduced word recall each trial may help differentiate MiND from no neurocognitive disorder, while reduced rate of verbal learning acquisition may help differentiate MaND from MiND.
Gastrointestinal Microbiota Disruption and Risk of Colonization With Carbapenem-resistant Pseudomonas aeruginosa in Intensive Care Unit Patients
Authors: Pettigrew Melinda M , Gent Janneane F , Kong Yong , Halpin Alison Laufer , Pineles Lisa , Harris Anthony D , Johnson J Kristie
Published: October 2018

Background

Carbapenem-resistant Pseudomonas aeruginosa (CRPA) colonizes the gastrointestinal tract of intensive care unit (ICU) patients, and CRPA colonization puts patients at increased risk of CRPA infection. Prior studies have not examined relationships between the microbiota, medications, and CRPA colonization acquisition.

Methods

Data and perirectal swabs were obtained from a cohort of ICU patients at the University of Maryland Medical Center. Patients (N = 109) were classified into 3 groups by CRPA colonization-acquisition status and antimicrobial exposure. We conducted 16S ribosomal RNA gene sequencing of an ICU admission swab and ≥1 additional swab and evaluated associations between patient characteristics, medications, the gastrointestinal microbiota, and CRPA colonization acquisition.

Results

ICU patients had low levels of diversity and high relative abundances of pathobionts. Piperacillin-tazobactam was prescribed more frequently to patients with CRPA colonization acquisition than those without. Piperacillin-tazobactam was associated with low abundance of potentially protective taxa (eg, Lactobacillus and Clostridiales) and increased risk of Enterococcus domination (odds ratio [OR], 5.50; 95% confidence interval [CI], 2.03–14.92). Opioids were associated with dysbiosis in patients who did not receive antibiotics; potentially protective Blautia and Lactobacillus were higher in patients who did not receive opioids. Several correlated taxa, identified at ICU admission, were associated with lower risk of CRPA colonization acquisition (OR, 0.58; 95% CI, .38–.87).

Conclusions

Antibiotics differed in their impact on the microbiota, with piperacillin-tazobactam being particularly damaging. Certain bacterial taxa (eg, Clostridiales) were negatively associated with CRPA colonization acquisition. These taxa may be markers of risk for CRPA colonization acquisition and/or serve a protective role.
Evaluation of Legendre polynomials by a three-term recurrence in floating-point arithmetic
Authors: Hrycak Tomasz , Schmutzhard Sebastian
Published: October 2018

We prove new error estimates for a three-term recurrence that is used to compute Legendre polynomials. To this end we derive a bilinear representation of the cross-product of Legendre functions and demonstrate estimates of the cross-product that are needed in the error analysis of the recurrence.
Recovery operators, paraconsistency and duality
Authors: Carnielli Walter , Coniglio Marcelo E , Rodrigues Abilio
Published: October 2018

There are two foundational, but not fully developed, ideas in paraconsistency, namely, the duality between paraconsistent and intuitionistic paradigms, and the introduction of logical operators that express metalogical notions in the object language. The aim of this paper is to show how these two ideas can be adequately accomplished by the logics of formal inconsistency (LFIs) and by the logics of formal undeterminedness (LFUs). LFIs recover the validity of the principle of explosion in a paraconsistent scenario, while LFUs recover the validity of the principle of excluded middle in a paracomplete scenario. We introduce definitions of duality between inference rules and connectives that allow comparing rules and connectives that belong to different logics. Two formal systems are studied, the logics mbC and mbD, that display the duality between paraconsistency and paracompleteness as a duality between inference rules added to a common core—in the case studied here, this common core is classical positive propositional logic. The logics mbC and mbD are equipped with recovery operators that restore classical logic for, respectively, consistent and determined propositions. These two logics are then combined obtaining a pair of LFI and undeterminedness, namely, mbCD and mbCDE. The logic mbCDE exhibits some nice duality properties. Besides, it is simultaneously paraconsistent and paracomplete, and able to recover the principles of excluded middle and explosion one at a time. The last sections offer an algebraic account for such logics by adapting the swap structures semantics framework of the LFIs the LFUs. This semantics highlights some subtle aspects of these logics, and allows us to prove decidability by means of finite nondeterministic matrices.
Music and cremation rituals in The Netherlands: A fine-grained analysis of a crematorium’s playlist
Authors: van der Smissen Doris , Steenbakker Margaret A , Hoondert Martin J M , van Zaanen Menno M
Published: October 2018

Although music is an important part of cremation rituals, there is hardly any research regarding music and cremations. This lack of research has inspired the authors to conduct a long-term research project, focusing on musical and linguistic aspects of music played during cremations. This article presents the analysis of a playlist consisting of twenty-five sets of music, each consisting of three tracks, used in a crematorium in the south of The Netherlands from 1986 onward. The main objective is to identify the differences and similarities of the twenty-five sets of musical tracks regarding content and musical properties. Consequently, we aim to provide insight in the history of (music played during) cremation rituals in The Netherlands. To analyze the musical properties of the sets, the authors use both a qualitative approach (close reading and musical analysis) and a computational analysis approach. The article demonstrates that a combination of a close reading and musical analysis and a computational analysis is necessary to explain the differences in properties of the sets. The presented multi-method approach may allow for comparisons against musical preferences in the context of current cremations, which makes it possible to trace the development of music and cremation rituals.
The Prognostic Significance of a Cast Fourth Ventricle in Ruptured Aneurysm Patients With Intraventricular Hemorrhage in the Barrow Ruptured Aneurysm Trial (BRAT)
Authors: Catapano Joshua S , Zabramski Joseph M , Baranoski Jacob F , Brigeman Scott , Morgan Clinton D , Hendricks Benjamin K , Mooney Michael A , Albuquerque Felipe C , Nakaji Peter , Spetzler Robert F
Published: October 2018

BACKGROUND

Ruptured aneurysms causing intraventricular hemorrhage (IVH) are associated with high morbidity. The presence of blood that completely fills the fourth ventricle (cast fourth ventricle, CFV) is thought to be particularly ominous, but studies documenting the outcome of such cases are lacking.

OBJECTIVE

To investigate the outcomes of patients with aneurysmal subarachnoid hemorrhage (aSAH) and CFV.

METHODS

We reviewed 406 patients enrolled in the Barrow Ruptured Aneurysm Trial (BRAT, NCT01593267, clinicaltrials.gov); 238 patients with aSAH and IVH were identified, and imaging was reviewed for the presence of CFV. Outcome was evaluated at the 1-yr follow-up. A poor outcome was defined as modified Rankin Scale score >2.

RESULTS

CFV was identified in 25 patients. Admission Glasgow Coma Score was lower in CFV patients, 7.8 versus 11.5 (P < .001). At discharge and the 1-yr follow-up, patients with CFV had a greater risk of a poor outcome (P < .001 and P = .002, respectively). In a subgroup analysis of 79 patients with IVH and initial Glasgow Coma Score ≤ 8, almost 50% of the patients with IVH but without CFV had made a good recovery versus 7% of patients with CFV (odds ratio [OR] 15, P = .002). On multivariate analysis, CFV was a greater predictor of a poor prognosis at 1 yr post-aSAH than Hunt and Hess grade >3 (6.4 OR vs 2.9 OR [P < .001], respectively).

CONCLUSION

The presence of CFV is a predictor of poor outcome in patients with aSAH. When compared to other patients with IVH and aSAH, CFV is a stronger predictor of a poor outcome than a poor Hunt and Hess Grade.
TYPE TESTING OF LiF:Mg,Cu,P (TLD-100H) WHOLE-BODY DOSEMETERS FOR THE ASSESSMENT OF Hp(10) AND Hp(0.07)
Authors: Pereira J S , Pereira M F , Rangel S , Caldeira M , Carvalhal G , Santos L M , Cardoso J V , Alves J G
Published: October 2018

In this work, the initial results of the type testing of the LiF:Mg,Cu,P (TLD-100H) whole-body personal dosemeters are presented. An assessment of reproducibility, linearity of the response, the residual signal as a function of the dose, energy and angular dependence of the response was performed. In general, the dosemeters show good reproducibility for different dose values and a linear behaviour for a range between 0.1 and 300 mSv. The detection limits obtained are lower than 50 μSv. The system presents a good energy and angular response for different radiation qualities.
Xylella fastidiosa in Olive in Apulia: Where We Stand
Authors: Saponari M. , Giampetruzzi A. , Loconsole G. , Boscia D. , Saldarelli P.
Published: October 2018

A dramatic outbreak of Xylella fastidiosa decimating olive was discovered in 2013 in Apulia, Southern Italy. This pathogen is a quarantine bacterium in the European Union (EU) and created unprecedented turmoil for the local economy and posed critical challenges for its management. With the new emerging threat to susceptible crops in the EU, efforts were devoted to gain basic knowledge on the pathogen biology, host, and environmental interactions (e.g., bacterial strain(s) and pathogenicity, hosts, vector(s), and fundamental drivers of its epidemics) in order to find means to control or mitigate the impacts of the infections. Field surveys, greenhouse tests, and laboratory analyses proved that a single bacterial introduction occurred in the area, with a single genotype, belonging to the subspecies pauca, associated with the epidemic. Infections caused by isolates of this genotype turned to be extremely aggressive on the local olive cultivars, causing a new disease termed olive quick decline syndrome. Due to the initial extension of the foci and the rapid spread of the infections, eradication measures (i.e., pathogen elimination from the area) were soon replaced by containment measures including intense border surveys of the contaminated area, removal of infected trees, and mandatory vector control. However, implementation of containment measures encountered serious difficulties, including public reluctance to accept control measures, poor stakeholder cooperation, misinformation from some media outlets, and lack of robust responses by some governmental authorities. This scenario delayed and limited containment efforts and allowed the bacterium to continue its rapid dissemination over more areas in the region, as shown by the continuous expansion of the official borders of the infected area. At the research level, the European Commission and regional authorities are now supporting several programs aimed to find effective methods to mitigate and contain the impact of X. fastidiosa on olives, the predominant host affected in this epidemic. Preliminary evidence of the presence of resistance in some olive cultivars represents a promising approach currently under investigation for long-term management strategies. The present review describes the current status of the epidemic and major research achievements since 2013.
Five-year Changes in Methamphetamine Use, Dependence, and Remission in a Community-recruited Cohort
Authors: Lanyon Chloe , Nambiar Dhanya , Higgs Peter , Dietze Paul , Quinn Brendan
Published: October 2018

Objectives:

Investigate patterns of methamphetamine use over time, specifically factors associated with remission from dependent and harmful patterns of use; and examine drug treatment and health/support service utilization pathways among people who use methamphetamine.

Methods:

People who regularly use methamphetamine were recruited from nontreatment settings in Melbourne, Australia, in 2010, and followed up twice over 5 years. Trajectories of past-month methamphetamine use and methamphetamine dependence were mapped. Random-effects logistic regression modeling identified factors associated with these outcomes.

Results:

Overall, past-month methamphetamine use and methamphetamine dependence decreased among the cohort over the study period. Variability in methamphetamine use and dependence trajectories was observed; 56% of participants achieved past-month abstinence; however, 14% subsequently relapsed and 44% reported past-month use at every time-point. During the study period, 27% of participants were never classified methamphetamine-dependent, 30% remitted from dependence, and 23% were consistently classified dependent. Factors independently associated with past-month methamphetamine use included male sex and poor physical health. Factors independently associated with methamphetamine dependence included poor physical health, low self-perceived social support, current mental health medication prescription, and current engagement with drug treatment services for methamphetamine use. Engagement with treatment and health/support services remained low (12%–22%) over the study period.

Conclusions:

Our findings indicate people who remit from methamphetamine dependence, reduce their frequency of use or cease entirely can maintain this over long periods. Initiatives addressing social determinants of health could be optimal for combating methamphetamine dependence. Community-based frontline service providers should be educated in relation to appropriately addressing methamphetamine use.
Total Intravenous Anesthesia versus Inhalation Anesthesia for Breast Cancer Surgery
Authors: Yoo Seokha , Lee Han-Byoel , Han Wonshik , Noh Dong-Young , Park Sun-Kyung , Kim Won Ho , Kim Jin-Tae
Published: October 2018

EDITOR’S PERSPECTIVE

What We Know about This Topic

IV anesthesia may impair anticancer immunity less than volatile anesthesia and therefore reduce recurrence risk

What This Article Tells Us That Is New

In a large propensity-matched retrospective cohort analysis, the authors compared total IV and volatile anesthesia for breast cancer surgery

Recurrence hazard was similar with each approach

Selection of IV or volatile anesthesia should be based on factors other than cancer recurrence

Background

The association between type of anesthesia used and recurrence of cancer remains controversial. This retrospective cohort study compared the influence of total IV anesthesia and inhalation anesthesia on the primary outcome of recurrence-free survival after breast cancer surgery.

Methods

The authors reviewed the electronic medical records of patients who had breast cancer surgery at a tertiary care teaching hospital between January 2005 and December 2013. The patients were grouped according to whether IV or inhalation anesthesia was used for surgery. Propensity score matching was used to account for differences in baseline characteristics. Kaplan–Meier survival curves were constructed to evaluate the influence of type of anesthesia on recurrence-free survival and overall survival. The risks of cancer recurrence and all-cause mortality were compared between each type of anesthesia.

Results

Of 7,678 patients who had breast cancer surgery during the study period, data for 5,331 patients were available for analysis (IV group, n = 3,085; inhalation group, n = 2,246). After propensity score matching, 1,766 patients remained in each group. Kaplan–Meier survival curves showed that there was no significant difference in recurrence-free survival or overall survival between the two groups, with 5-yr recurrence-free survival rates of 93.2% (95% CI, 91.9 to 94.5) in the IV group and 93.8% (95% CI, 92.6 to 95.1) in the inhalation group. Inhalation anesthesia had no significant impact on recurrence-free survival (hazard ratio, 0.96; 95% CI, 0.69 to 1.32; P = 0.782) or overall survival (hazard ratio, 0.96; 95% CI, 0.69 to 1.33, P = 0.805) when compared with total IV anesthesia.

Conclusions

The authors found no association between type of anesthesia used and the long-term prognosis of breast cancer. The results of this retrospective cohort study do not suggest specific selection of IV or inhalation anesthesia for breast cancer surgery.
Organ System Anomalies Associated With Congenital Scoliosis: A Retrospective Study of 305 Patients
Authors: Furdock Ryan , Brouillet Kirsten , Luhmann Scott J.
Published: October 2018

Design:

Retrospective analyses of congenital scoliosis patients at 2 tertiary care pediatric hospitals.

Objective:

This study objectives were (1) to report the rates of anomalies of 10 organ systems in congenital scoliosis patients and (2) to determine whether the presence of a single organ system anomaly increases the rate of nonspinal organ system defects.

Summary of Background Data:

Intraspinal, cardiac, renal, and gastrointestinal anomalies have been reported to occur at higher rates in congenital scoliosis than the normal population. It is unknown whether the presence of 1 organ system defect increases the risk of nonspinal organ system anomalies.

Methods:

All patients diagnosed, evaluated in the outpatient setting, with congenital scoliosis who were below 18 years of age at time of presentation with available cardiac echo, renal ultrasound, or magnetic resonance imaging were included in this study.

Results:

There were 305 patients (161 females, 53%) whose mean age was 7+3 years. In total, 84% of patients were observed to have at least 1 organ defect. Overall, 22% of patients had 1 organ defect, 19% had 2, 18% had 3, and 18% had ≥4 organ defects. There was an average of 2.2 anomalies per patient (range=0 to 8). Intraspinal anomalies were documented in 43% of patients; syrinx occurred most frequently. Urogenital anomalies were documented in 39% of patients; solitary kidney was most prevalent. Cardiac anomalies were documented in 54% of patients; ventricular septal defect was most common. In 12% of patients, the triad of spinal, urogenital, and cardiac defects was observed. Multiple organ systems were found to have significant associations (P<0.05) in anomaly development.

Conclusions:

Cardiac anomalies were the most common defect (54%), and occurred at a rate >2 times higher than previously reported. The high rate of intraspinal, cardiac, and urogenital defects makes magnetic resonance imaging, echocardiography, and renal ultrasound a critical part of evaluation for all congenital scoliosis patients.

Level of Evidence:

Level II.
Clinical experience with combination BRAF/MEK inhibitors for melanoma with brain metastases: a real-life multicenter study
Authors: Drago Joshua Z. , Lawrence Donald , Livingstone Elisabeth , Zimmer Lisa , Chen Tianqi , Giobbie-Hurder Anita , Amann Valerie C. , Mangana Joanna , Siano Marco , Zippelius Alfred , Dummer Reinhard , Goldinger Simone M. , Sullivan Ryan J.
Published: October 2018

BRAF and MEK kinase inhibitors can be highly effective in treating BRAF-mutant melanomas, but their safety and activity in patients with active/symptomatic brain metastases are unclear. We sought to shed light on this open clinical question. We conducted a multicenter retrospective study on real-life patients with melanoma and active brain metastases treated with combination BRAF/MEK inhibitors. A total of 65 patients were included (38 men and 27 women; median age: 49 years). Of them, 53 patients received dabrafenib/trametinib, 10 received vemurafenib/cobimetinib, one received encorafenib/binimetinib, and one received vemurafenib/trametinib. We did not observe any unexpected treatment-related safety signals in our cohort. Overall, 17 patients continued on therapy through the cutoff date. After initiation of therapy, steroid dose could be decreased in 22 of 33 patients (11 tapered off entirely), anticonvulsants were stopped in four of 21, and narcotics were stopped in four of 12. Median progression-free survival from the start of therapy was 5.3 months (95% confidence interval: 3.6–6.1), and median overall survival was 9.5 months (95% confidence interval: 7.7–13.5). A total of 20 patients were surviving at the cutoff date. Univariate analysis of age, sex, ulceration status, thickness, stage, location, or lactate dehydrogenase did not reveal significant predictors of progression-free survival or overall survival within our cohort, but multivariate analysis suggested that older age, lower risk location of original lesion, and nodular melanoma are poor prognostic indicators. Combination therapy with BRAF/MEK inhibitors is a viable treatment option for patients with BRAF-mutant melanoma and brain metastases, but further studies should help to define the optimal treatment approach in this population.
Functional and molecular changes in the nucleus accumbens of MK-801-sensitized rats
Authors: Lefevre Emilia , Gooch Helen , Josh Peter , Alexander Suzy , Eyles Darryl W. , Burne Thomas H.J.
Published: October 2018

Behavioural sensitization is a putative mechanism in the pathophysiology of drug addiction and neuropsychiatric disorders such as schizophrenia. In rodents, drug-induced behavioural sensitization has been described for several different drug classes. The N-methyl-d-aspartate receptor antagonist MK-801 can inhibit sensitization to other drugs of abuse. However, MK-801 also produces behavioural sensitization to its own hyperlocomotor inducing effects, suggesting that MK-801 sensitization has a distinctive mechanism of action. The aim of this study was to carry out a functional and molecular analysis of the nucleus accumbens (NAc) of adult male Sprague-Dawley rats sensitized to MK-801 (seven daily injections of 0.25 mg/kg, 5 days of withdrawal and subsequent 0.25 mg/kg challenge), or following acute MK-801 (0.25 mg/kg), or naive rats as controls. Locomotor activity was the primary measure of sensitization. Ex-vivo slice electrophysiology showed a decrease in the excitatory synaptic strength in the NAc of rats sensitized to MK-801 compared with acute MK-801 treatment or naive controls. An LC–MS/MS SWATH proteomics approach showed that proteins altered by MK-801 sensitization were predominantly related to functions including calcium and glutamate signalling, and mitochondrial dysfunction. These results shed some light on neural changes in the NAc after sensitization to MK-801. This model could prove useful for studying the role of N-methyl-d-aspartate receptors in the pathophysiology of drug addiction and schizophrenia.
Normal extinction and reinstatement of morphine-induced conditioned place preference in the GluA1-KO mouse line
Authors: Kiiskinen Tuomo , Korpi Esa R. , Aitta-aho Teemu
Published: October 2018

Extinction and reinstatement of morphine-induced conditioned place preference were studied in glutamate α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid-receptor GluA1 subunit-deficient mice (global GluA1-KO mice). In line with previous findings, both acquisition and expression of conditioned place preference to morphine (20 mg/kg, subcutaneously) were fully functional in GluA1 KO mice compared with wild-type littermate controls (GluA1-WT), thus enabling the study of extinction. With a 10-session extinction paradigm, the GluA1 KO mice showed complete extinction similar to that of the GluA1-WT mice. Morphine-induced reinstatement (10 mg/kg, subcutaneously) was detected in both mouse lines. GluA1 KO mice moved more during all the phases of the experiment, including the place conditioning trials, extinction sessions, and place preference tests. The results suggest that the GluA1 subunit may be dispensable or prone to compensation at the neural circuitries delineating extinction and reinstatement. The GluA1 KO mice show altered long-term between-session habituation, which extends longer than previously anticipated.
Clinical Reasoning and Knowledge Organization: Bridging the Gap Between Medical Education and Neurocognitive Science
Authors: Longo Palma J. , Orcutt Venetia L. , James Kassidy , Kane John , Coleman Veronica
Published: October 2018

Purpose

The purpose of this pilot study was 2-fold. The first was to investigate the conceptual relationship between previously validated methodologies. The second was to establish a linkage between medical education research and current neurocognitive science that accounts for knowledge organization during the clinical reasoning process.

Methods

Transcripts of Think Aloud interviews conducted after an objective structured clinical examination (n = 12) were coded and analyzed into 3 clinical reasoning competencies (semantic, diagnostic, and knowledge network organization). Correlational analyses were conducted to establish relationships between the 2 methodologies. Analyses of variance examined group differences.

Results

Significant correlations with large effect sizes were found between semantic, diagnostic, and knowledge network organization variables. Analysis of variance results approach significant difference in the knowledge network organization between weak versus strong diagnosticians.

Conclusions

Knowledge network organization measurement can be used to discern differences in clinical reasoning and may offer explanations for the variation in health professionals' diagnostic performance.
Fluid Balance and Recovery of Native Lung Function in Adult Patients Supported by Venovenous Extracorporeal Membrane Oxygenation and Continuous Renal Replacement Therapy
Authors: McCanny Peter , Smith Myles W. , O’Brien Serena G. , Buscher Hergen , Carton Edmund G.
Published: October 2018

Fluid overload is associated with increased mortality in adult patients with acute respiratory distress syndrome. In patients requiring venovenous extracorporeal membrane oxygenation (VV-ECMO), the effects of fluid removal on survival and lung recovery remain undefined. We assessed the impact of early fluid removal in adult patients supported by VV-ECMO and concomitant continuous renal replacement therapy, in an 18-bed tertiary intensive care unit between 2010 and 2015. Twenty-four patients met inclusion criteria, of these 15 (63%) survived to hospital discharge. In our patient group, a more negative cumulative daily fluid balance was strongly associated with improved pulmonary compliance (2.72 ml/cmH2O per 1 L negative fluid balance; 95% confidence interval [CI]: 1.61–3.83; P < 0.001). In addition, a more negative mean daily fluid balance was associated with improved pulmonary compliance (4.37 ml/cmH2O per 1 L negative fluid balance; 95% CI: 2.62–6.13; P < 0.001). Survivors were younger and had lower mean daily fluid balance (−0.33 L [95% CI: −1.22 to −0.06] vs. −0.07 L [95% CI: −0.76 to 0.06]; P = 0.438) and lower cumulative fluid balance up to day 14 (−4.60 L [95% CI: −8.40 to −1.45] vs. −1.00 L [95% CI: −4.60 to 0.90]; P = 0.325), although the fluid balance effect alone did not reach statistical significance.
Evaluation of Incidental Cardiac Masses on Computed Tomography Imaging
Authors: Bernheim Adam , Gore Ashwani , Goyal Nikhil
Published: October 2018

Cardiac masses encountered on imaging may present a diagnostic dilemma when discovered incidentally, or even when they serve as the principal reason for the examination. In this review, we present an algorithmic approach for assessing cardiac masses by integrating clinical information with radiologic findings to reach a specific diagnosis or a narrow differential diagnosis.
Endoscopic Removal of an Epithelial Cyst of the Zygoma
Authors: Fontenot Miles R. , Tolisano Anthony M. , Kutz Joe Walter
Published: October 2018

This study elaborates a brief overview of epithelial cysts in the bones of the skull and describes an unusual patient with an epidermoid cyst of the zygoma. This report focuses on an endoscopic preauricular infratemporal fossa approach for resection of a left epidermoid cyst of the zygoma. Preoperative magnetic resonance imaging and computed tomography imaging as well as intraoperative endoscopic images and movie were demonstrated. The epithelial cyst was successfully removed from the patient using a minimally invasive approach utilizing endoscopes. No complications were encountered. The possible causes of this rare presentation and minimal surgical removal utilizing endoscopes were discussed in this study. According to the authors, this is the first reported study of endoscopic removal of an epidermoid cyst from the zygomatic root. The patient's previous surgical history of a tympanoplasty could have contributed to the unusual location of the lesion.
A Standardized Perioperative Clinical Pathway for Uncomplicated Craniosynostosis Repair Is Associated With Reduced Hospital Resource Utilization
Authors: Lin Lawrence O. , McKenna Rachel A. , Zhang Rosaline S. , Hoppe Ian C. , Swanson Jordan W. , Bartlett Scott P. , Taylor Jesse A.
Published: October 2018

Background:

Hospital resource overutilization can significantly disrupt patient treatment such as cancelling surgical patients due to a lack of intensive care unit (ICU) space. The authors describe a clinical pathway (CP) designed to reduce ICU length of stay (LOS) for nonsyndromic single-suture craniosynostosis (nsSSC) patients undergoing cranial vault reconstruction (CVR) in order to minimize surgical disruptions and improve patient outcomes.

Methods:

A multidisciplinary team implemented a perioperative CP including scheduled laboratory testing to decrease ICU LOS. Hospital and ICU LOS, interventions, and perioperative morbidity—infection rate, cerebrospinal fluid (CSF) leaks, and unplanned return to the operating room (OR)—were compared using Mann–Whitney U, Fisher exact, and t tests.

Results:

Fifty-one ICU admissions were managed with the standardized CP and compared to 49 admissions in the 12 months prior to pathway implementation. There was a significant reduction in ICU LOS (control: mean 1.84 ± 0.93, median 1.89 ± 0.94; CP: mean 1.15 ± 0.34, median 1.03 ± 0.34 days; P < 0.001 for both). There were similar rates of hypotension requiring intervention (CP: 2, control: 1; P = 0.999), postoperative transfusion (CP: 3, control: 0; P = 0.243), and artificial ventilation (CP: 1, control: 0; P = 0.999). Perioperative morbidity such as infection (CP: 1, control: 0; P = 0.999), return to the OR (CP: 1, control: 0; P = 0.999), and CSF leak (no leaks; P = 0.999) was also similar.

Conclusion:

Implementation of a standardized perioperative CP for nsSSC patients resulted in a significantly shorter ICU LOS without a measured change in perioperative morbidity. Pathways such as the one described that improve patient throughput and decrease resource utilization benefit craniofacial teams in conducting an efficient service while providing high-quality care.
Characterizing the underlying diagnoses for exploratory laparotomies to improve risk-adjustment models of postoperative mortality
Authors: Mehta Ambar , Lunardi Nicole , Efron David T. , Joseph Bellal A. , Steven Kent A. , Manukyan Mariuxi , Fakhry Samir M. , Sakran Joseph V.
Published: October 2018

BACKGROUND

Surgeons perform emergent exploratory laparotomies (ex-laps) for a myriad of surgical diagnoses. We characterized common diagnoses for which emergent ex-laps were performed and leveraged these groups to improve risk-adjustment models for postoperative mortality.

METHODS

Using American Association for the Surgery of Trauma criteria, we identified hospitalizations where the primary procedure was an emergent ex-lap in the 2012 to 2014 (derivation cohort) and 2015 (validation cohort) Nationwide Inpatient Sample. After tabulating all International Classification of Diseases—9th Rev.—Clinical Modification diagnosis codes within these hospitalizations, we divided them into clinically relevant groups. Using two stepwise regression paradigms—forward selection and backward elimination—we identified diagnostic groups significantly associated with postoperative mortality in multivariable logistic regressions. We evaluated the addition of these groups as individual covariates in risk-adjustment models for postoperative mortality using the area under the receiver operator characteristic curve. All regressions additionally adjusted for clinical factors and hospital clustering.

RESULTS

We identified 4127 patients in the derivation cohort (median age, 50 years; 46.0% female; 62.1% white), with an overall mortality rate of 13.4%. Among all patients, we tabulated a total of 164 diagnosis codes, of which 27 (16.5%) may have led to an emergent ex-lap. These 27 codes clinically represented seven diagnostic categories, which captured a majority of the patients (70.4%). Backward elimination and forward selection led to four common diagnosis categories associated with mortality: bleeding, obstruction, shock, and ischemia. Adjusting for these four diagnostic groups in a multivariable logistic regression assessing postoperative mortality increased the area under the receiver operator characteristic curve from 74.5% to 88.2% in the derivation cohort and from 73.8% to 88.2% in the validation cohort.

CONCLUSION

Seven diagnostic groups account for the majority of the emergent ex-laps. Adjusting for four groups may improve the accuracy of risk-adjustment models for mortality and validating such analytic standardization may optimize best research practices for EGS procedures.

LEVEL OF EVIDENCE

Prognostic and epidemiologic, Level III.