bluuebunny/crossref_metadata_2025_split huggingface dataset:
Multiple imputation using linked proxy outcome data resulted in important bias reduction and efficiency gains: a simulation study
Authors: Cornish R. P. , Macleod J. , Carpenter J. R. , Tilling K. 
Published: December 2017

Abstract
Background
When an outcome variable is missing not at random (MNAR: probability of missingness depends on outcome values), estimates of the effect of an exposure on this outcome are often biased. We investigated the extent of this bias and examined whether the bias can be reduced through incorporating proxy outcomes obtained through linkage to administrative data as auxiliary variables in multiple imputation (MI).

Methods
Using data from the Avon Longitudinal Study of Parents and Children (ALSPAC) we estimated the association between breastfeeding and IQ (continuous outcome), incorporating linked attainment data (proxies for IQ) as auxiliary variables in MI models. Simulation studies explored the impact of varying the proportion of missing data (from 20 to 80%), the correlation between the outcome and its proxy (0.1–0.9), the strength of the missing data mechanism, and having a proxy variable that was incomplete.

Results
Incorporating a linked proxy for the missing outcome as an auxiliary variable reduced bias and increased efficiency in all scenarios, even when 80% of the outcome was missing. Using an incomplete proxy was similarly beneficial. High correlations (> 0.5) between the outcome and its proxy substantially reduced the missing information. Consistent with this, ALSPAC analysis showed inclusion of a proxy reduced bias and improved efficiency. Gains with additional proxies were modest.

Conclusions
In longitudinal studies with loss to follow-up, incorporating proxies for this study outcome obtained via linkage to external sources of data as auxiliary variables in MI models can give practically important bias reduction and efficiency gains when the study outcome is MNAR.
Diagnostic accuracy of resting systolic toe pressure for diagnosis of peripheral arterial disease in people with and without diabetes: a cross‐sectional retrospective case‐control study
Authors: Tehan Peta Ellen , Barwick Alex Louise , Sebastian Mathew , Chuter Vivienne Helaine 
Published: December 2017

AbstractBackgroundThe resting systolic toe pressure (TP) is a measure of small arterial function in the periphery. TP is used in addition to the ankle‐brachial index when screening for peripheral arterial disease (PAD) of the lower limb in those with diabetes, particularly in the presence of lower limb medial arterial calcification. It may be used as an adjunct assessment of lower limb vascular function and as a predictor of wound healing. The aim of this study was to determine the diagnostic accuracy of TP for detecting PAD in people with and without diabetes.MethodsThis was a retrospective case‐control study. Two researchers extracted information from consecutive patient records, including TP measurements, colour Duplex ultrasound results, demographic information, and medical history. Measures of diagnostic accuracy were determined by receiver operating curve (ROC) analysis, and calculation of sensitivity, specificity, and positive and negative likelihood ratios.ResultsThree hundred and nintey‐four participants with suspected PAD were included. In the diabetes group (n = 176), ROC analysis of TP for detecting PAD was 0.78 (95%CI: 0.69 to 0.84). In the control group (n = 218), the ROC of TP was 0.73 (95%CI: 0.70 to 0.80). TP had highest sensitivity when anatomical distribution of disease was both proximal and distal (diabetes group: 79.49%, the control group: 82.61%). TP yielded highest sensitivity in mild disease (50–75% stenosis) in diabetes group, (81.82%) and moderate disease (>75% stenosis) in control group (80.77%).ConclusionsOur findings indicate that TPs are useful to assist in diagnosing PAD in clinical practice, however, results should be interpreted with caution due to the small probability of PAD being present with a negative test.
Modifiable and Nonmodifiable Factors Associated With Perioperative Failure of Extraglottic Airway Devices
Authors: Vannucci Andrea , Rossi Isabella T. , Prifti Kevin , Kallogjeri Dorina , Rangrass Govind , DeCresce David , Brenner Daniel , Lakshman Neel , Helsten Daniel L. , Cavallone Laura F. 
Published: December 2017

BACKGROUND:
Extraglottic airway device (EGA) failure can be associated with severe complications and adverse patient outcomes. Prior research has identified patient- and procedure-related predictors of EGA failure. In this retrospective study, we assessed the incidence of perioperative EGA failure at our institution and identified modifiable factors associated with this complication that may be the target of preventative or mitigating interventions.

METHODS:
We performed a 5-year retrospective analysis of adult general anesthesia cases managed with EGAs in a single academic center. Univariable and multivariable logistic regressions were used to identify clinically modifiable and nonmodifiable factors significantly associated with 3 different types of perioperative EGA failure: (1) “EGA placement failure,” (2) “EGA failure before procedure start,” and (3) “EGA failure after procedure start.”

RESULTS:
A total of 19,693 cases involving an EGA were included in the analysis dataset. EGA failure occurred in 383 (1.9%) of the cases. EGA placement failure occurred in 222 (1.13%) of the cases. EGA failure before procedure start occurred in 76 (0.39%) of the cases. EGA failure after procedure start occurred in 85 (0.43%) of the cases. Factors significantly associated with each type of failure and controllable by the anesthesia team were as follows: (1) EGA placement failure: use of desflurane (odds ratio [OR], 1.67; 95% confidence interval [CI], 1.23–2.25) and EGA size 4 or 5 vs 2 or 3 (OR, 0.07; 95% CI, 0.05–0.10); (2) EGA failure before procedure start: use of desflurane (OR, 2.05; 95% CI, 1.23–3.40) and 3 or more placement attempts (OR, 4.69; 95% CI, 2.57–8.56); and (3) EGA failure after procedure start: 3 or more placement attempts (OR, 2.06; 95% CI, 1.02–4.16) and increasing anesthesia time (OR, 1.35; 95% CI, 1.17–1.55).

CONCLUSIONS:
The overall incidence of EGA failure was 1.9%, and EGA placement failure was the most common type of failure. We also found that use of desflurane and use of smaller EGA sizes in adult patients were factors under the direct control of anesthesia clinicians associated with EGA failure. An increasing number of attempts at EGA placement was associated with later device failures. Our findings also confirm the association of EGA failure with previously identified patient- and procedure-related factors such as increased body mass index, male sex, and position other than supine.
Differential Effects of Anesthetics and Opioid Receptor Activation on Cardioprotection Elicited by Reactive Oxygen Species–Mediated Postconditioning in Sprague-Dawley Rat Hearts
Authors: Lucchinetti Eliana , Lou Phing-How , Gandhi Manoj , Clanachan Alexander S. , Zaugg Michael 
Published: December 2017

BACKGROUND:
Despite an array of cardioprotective interventions identified in preclinical models of ischemia–reperfusion (IR) injury, successful clinical translation has not been achieved. This study investigated whether drugs routinely used in clinical anesthesia influence cardioprotective effectiveness by reducing effects of reactive oxygen species (ROS), upstream triggers of cardioprotective signaling. Effects of propofol, sevoflurane, or remifentanil were compared on postischemic functional recovery induced by ROS-mediated postconditioning with Intralipid.

METHODS:
Recovery of left ventricular (LV) work, an index of IR injury, was measured in isolated Sprague-Dawley rat hearts subjected to global ischemia (20 minutes) and reperfusion (30 minutes). Hearts were either untreated or were treated with postconditioning with Intralipid (1%, throughout reperfusion). Propofol (10 μM), sevoflurane (2 vol%), remifentanil (3 nM), or combinations thereof were administered peri-ischemically (before and during IR). The effects of anesthetics on ROS production were measured in LV cardiac fibers by Amplex Red assay under phosphorylating and nonphosphorylating conditions.

RESULTS:
Recovery of LV work (expressed as percentage of the preischemic value ± standard deviation) in untreated hearts was poor (20% ± 7%) and was improved by Intralipid postconditioning (58% ± 8%, P = .001). In the absence of Intralipid postconditioning, recovery of LV work was enhanced by propofol (28% ± 9%, P = .049), sevoflurane (49% ± 5%, P < .001), and remifentanil (51% ± 6%, P < .001). The benefit of Intralipid postconditioning was abolished by propofol (33% ± 10%, P < .001), but enhanced by sevoflurane (80% ± 7%, P < .001) or remifentanil (80% ± 9%, P < .001). ROS signaling in LV fibers was abolished by propofol, but unaffected by sevoflurane or remifentanil. We conclude that propofol abolishes ROS-mediated Intralipid postconditioning by acting as a ROS scavenger. Sevoflurane and remifentanil are protective per se and provide additive cardioprotection to ROS-mediated cardioprotection.

CONCLUSIONS:
These divergent effects of routinely used drugs in clinical anesthesia may influence the translatability of cardioprotective therapies such as Intralipid postconditioning.
Macintosh Blade Videolaryngoscopy Combined With Rigid Bonfils Intubation Endoscope Offers a Suitable Alternative for Patients With Difficult Airways
Authors: Pieters Barbe M. , Theunissen Maurice , van Zundert Andre A. 
Published: December 2017

BACKGROUND:
In the armamentarium of an anesthesiologist, videolaryngoscopy is a valuable addition to secure the airway. However, when the videolaryngoscope (VLS) offers no solution, few options remain. Earlier, we presented an intubation technique combining Macintosh blade VLS and Bonfils intubation endoscope (BIE) for a patient with a history of very difficult intubation. In the present study, we evaluated this technique to establish whether it is a valuable alternative.

METHODS:
In this single-blinded nonrandomized study, 38 patients with a history of difficult intubation or 1 or more predictors of difficult intubation, scoring a Cormack & Lehane (C&L) grade III or IV using Macintosh blade VLS, were included. Patients were intubated combining the VLS with the BIE. The C&L grade was scored 3 times during (1) direct laryngoscopy; (2) indirect videolaryngoscopy; and (3) using the combined technique (VLS + BIE). Afterward, 2 blinded anesthesiologists assessed the C&L grade using the pictures taken during the procedure.

RESULTS:
Data of 38 patients were analyzed. An improvement of the C&L grade with the combined technique occurred in 33 of 38 patients (86.8%; 95% confidence interval, 71.9%–95.6%). Reviewer 1 reported an improvement of the C&L grade with the combined technique in 37 of 38 patients. Reviewer 2 reported improvement in 33 and deterioration in 2 of the patients. No complications occurred.

CONCLUSIONS:
The combined use of a VLS with Macintosh blade and BIE gives the anesthesiologist a valuable alternative intubation option in patients with extremely difficult airways.
Inclusion criteria update for the rat intraluminal ischaemic model for preclinical studies
Authors: Fernández-Susavila Héctor , Iglesias-Rey Ramón , Dopico-López Antonio , Pérez-Mato María , Sobrino Tomás , Castillo José , Campos Francisco 
Published: December 2017

ABSTRACT
Proper occlusion of the medial cerebral artery, as determined by laser Doppler monitoring, during cerebral ischaemia in rat models is an important inclusion criterion in experimental studies. However, successful occlusion of the artery does not always guarantee a reproducible infarct volume, which is crucial for validating the efficacy of new protective drugs. In a rat intraluminal ischaemic model, laser Doppler monitoring alone was compared with laser Doppler monitoring in combination with magnetic resonance angiography (MRA) and diffusion-weighted imaging (DWI). Twenty-eight animals showed successful occlusion and reperfusion determined with Doppler monitoring, with an infarct size at 24 h of 16.7±11.5% (determined as ischaemic damage with respect to the ipsilateral hemisphere volume). However, when arterial occlusion and infarct damage were analysed in these animals using MRA and DWI, respectively, 15 animals were excluded and only 13 animals were included, with an infarct size at 24 h of 21.6±6.1%, showing a variability in the infarct size significantly lower (P&lt;0.05, F-test) than that obtained with Doppler monitoring alone. We also observed that blocking of the pterygopalatine artery (a maxillary artery that is usually occluded in the intraluminal ischaemic model) was not relevant for this model, at least in terms of infarct variability. These results show that laser Doppler monitoring is a necessary procedure, but not sufficient to guarantee a reproducible infarct volume, in a rat ischaemic model. Therefore, laser Doppler monitoring in combination with DWI and MRA represents a reliable inclusion protocol during ischaemic surgery for the analysis of new protective drugs.
Early VGLUT1-specific parallel fiber synaptic deficits and dysregulated cerebellar circuit in the KIKO mouse model of Friedreich ataxia
Authors: Lin Hong , Magrane Jordi , Clark Elisia M. , Halawani Sarah M. , Warren Nathan , Rattelle Amy , Lynch David R. 
Published: December 2017

ABSTRACT
Friedreich ataxia (FRDA) is an autosomal recessive neurodegenerative disorder with progressive ataxia that affects both the peripheral and central nervous system (CNS). While later CNS neuropathology involves loss of large principal neurons and glutamatergic and GABAergic synaptic terminals in the cerebellar dentate nucleus, early pathological changes in FRDA cerebellum remain largely uncharacterized. Here, we report early cerebellar VGLUT1 (SLC17A7)-specific parallel fiber (PF) synaptic deficits and dysregulated cerebellar circuit in the frataxin knock-in/knockout (KIKO) FRDA mouse model. At asymptomatic ages, VGLUT1 levels in cerebellar homogenates are significantly decreased, whereas VGLUT2 (SLC17A6) levels are significantly increased, in KIKO mice compared with age-matched controls. Additionally, GAD65 (GAD2) levels are significantly increased, while GAD67 (GAD1) levels remain unaltered. This suggests early VGLUT1-specific synaptic input deficits, and dysregulation of VGLUT2 and GAD65 synaptic inputs, in the cerebellum of asymptomatic KIKO mice. Immunohistochemistry and electron microscopy further show specific reductions of VGLUT1-containing PF presynaptic terminals in the cerebellar molecular layer, demonstrating PF synaptic input deficiency in asymptomatic and symptomatic KIKO mice. Moreover, the parvalbumin levels in cerebellar homogenates and Purkinje neurons are significantly reduced, but preserved in other interneurons of the cerebellar molecular layer, suggesting specific parvalbumin dysregulation in Purkinje neurons of these mice. Furthermore, a moderate loss of large principal neurons is observed in the dentate nucleus of asymptomatic KIKO mice, mimicking that of FRDA patients. Our findings thus identify early VGLUT1-specific PF synaptic input deficits and dysregulated cerebellar circuit as potential mediators of cerebellar dysfunction in KIKO mice, reflecting developmental features of FRDA in this mouse model.
Noncanonical NF-κB signaling and the essential kinase NIK modulate crucial features associated with eosinophilic esophagitis pathogenesis
Authors: Eden Kristin , Rothschild Daniel E. , McDaniel Dylan K. , Heid Bettina , Allen Irving C. 
Published: December 2017

ABSTRACT
Eosinophilic esophagitis (EoE) is an allergic disease of the esophagus driven by T cell and eosinophil responses to dietary allergens, resulting in chronic mucosal inflammation. Few spontaneous animal models of esophageal eosinophilia exist, with most studies relying on artificial sensitization procedures. NF-κB-inducing kinase (NIK; MAP3K14) is a key signaling molecule of the noncanonical NF-κB (NFKB1) pathway, an alternative signaling cascade producing chemokines involved in lymphoid stroma development and leukocyte trafficking. Nik−/− mice have been shown to develop a hypereosinophilic syndrome in peripheral blood and major filtering organs; however, the gastrointestinal mucosa of these mice has not been well characterized. We show that Nik−/− mice develop significant, localized eosinophilic esophagitis that mimics human EoE, including features such as severe eosinophil accumulation, degranulation, mucosal thickening, fibrosis and basal cell hyperplasia. The remainder of the GI tract, including the caudal stomach, small intestine and colon, in mice with active EoE are unaffected, also similar to human patients. Gene expression patterns in esophageal tissue of Nik−/− mice mimics human EoE, with thymic stromal lymphopoetin (TSLP) in particular also elevated at the protein level. In gene expression data sets from human biopsy specimens, we further show that many genes associated with noncanonical NF-κB signaling are significantly dysregulated in EoE patients, most notably a paradoxical upregulation of NIK itself with concurrent upregulation of powerful protein-level destabilizers of NIK. These findings suggest that Nik−/− mice could be useful as a spontaneous model of specific features of EoE and highlight a novel role for noncanonical NF-κB signaling in human patients.
New chimeric RNAs in acute myeloid leukemia
Authors: Rufflé Florence , Audoux Jerome , Boureux Anthony , Beaumeunier Sacha , Gaillard Jean-Baptiste , Bou Samra Elias , Megarbane Andre , Cassinat Bruno , Chomienne Christine , Alves Ronnie , Riquier Sebastien , Gilbert Nicolas , Lemaitre Jean-Marc , Bacq-Daian Delphine , Bougé Anne Laure , Philippe Nicolas , Commes Therese 
Published: December 2017

Background: High-throughput next generation sequencing (NGS) technologies enable the detection of biomarkers used for tumor classification, disease monitoring and cancer therapy. Whole-transcriptome analysis using RNA-seq is important, not only as a means of understanding the mechanisms responsible for complex diseases but also to efficiently identify novel genes/exons, splice isoforms, RNA editing, allele-specific mutations, differential gene expression and fusion-transcripts or chimeric RNA (chRNA). Methods: We used Crac, a tool that uses genomic locations and local coverage to classify biological events and directly infer splice and chimeric junctions within a single read. Crac’s algorithm extracts transcriptional chimeric events irrespective of annotation with a high sensitivity, and CracTools was used to aggregate, annotate and filter the chRNA reads. The selected chRNA candidates were validated by real time PCR and sequencing. In order to check the tumor specific expression of chRNA, we analyzed a publicly available dataset using a new tag search approach. Results: We present data related to acute myeloid leukemia (AML) RNA-seq analysis. We highlight novel biological cases of chRNA, in addition to previously well characterized leukemia chRNA. We have identified and validated 17 chRNAs among 3 AML patients: 10 from an AML patient with a translocation between chromosomes 15 and 17 (AML-t(15;17), 4 from patient with normal karyotype (AML-NK) 3 from a patient with chromosomal 16 inversion (AML-inv16). The new fusion transcripts can be classified into four groups according to the exon organization. Conclusions: All groups suggest complex but distinct synthesis mechanisms involving either collinear exons of different genes, non-collinear exons, or exons of different chromosomes. Finally, we check tumor-specific expression in a larger RNA-seq AML cohort and identify new AML biomarkers that could improve diagnosis and prognosis of AML.
Predictive value of early postoperative IOP and bleb morphology in Mitomycin-C augmented trabeculectomy
Authors: Esfandiari Hamed , Pakravan Mohammad , Loewen Nils A. , Yaseri Mehdi 
Published: December 2017

Background: To determine the predictive value of postoperative bleb morphological features and intraocular pressure (IOP) on the success rate of trabeculectomy. Methods: In this prospective interventional case series, we analyzed for one year 80 consecutive primary open angle glaucoma patients who underwent mitomycin-augmented trabeculectomy. Bleb morphology was scored using the Indiana bleb appearance grading scale (IBAGS). Success was defined as IOP ≤15 mmHg at 12 months. We applied a multivariable regression analysis and determined the area under the receiver operating characteristic curve (AUC). Results: The mean age of participants was 62±12.3 years in the success and 63.2±16.3 years in the failure group (P= 0.430) with equal gender distribution (P=0.911). IOPs on day 1, 7 and 30 were similar in both (P= 0.193, 0.639, and 0.238, respectively.) The AUC of IOP at day 1, day 7 and 30 for predicting a successful outcome was 0.355, 0.452, and 0.80, respectively. The AUC for bleb morphology parameters of bleb height, extension, and vascularization, on day 14 were 0.368, 0.408, and 0.549, respectively. Values for day 30 were 0.428, 0.563, and 0.654. IOP change from day 1 to day 30 was a good predictor of failure (AUC=0.838, 95% CI: 0.704 to 0.971) with a change of more than 3 mmHg predicting failure with a sensitivity of 82.5% (95% CI: 68 to 91%) and a specificity of 87.5% (95% CI: 53 to 98%). Conclusions: IOP on day 30 had a fair to good accuracy while bleb features failed to predict success except bleb vascularity that had a poor to fair accuracy. An IOP increase more than 3 mmHg during the first 30 days was a good predictor of failure.
Pricing with Cookies: Behavior-Based Price Discrimination and Spatial Competition
Authors: Choe Chongwoo , King Stephen , Matsushima Noriaki 
Published: December 2017

We present a model of dynamic competition between two firms where firms gather customer information through first-period purchase. This creates asymmetric information in the second period whereby a firm knows more about its own past customers than its competitor does. We examine how the ability to offer personalized prices based on customer information affects prices and profit over the two periods. When product differentiation is exogenously fixed, asymmetric information leads to two asymmetric equilibria where one firm chooses more aggressive pricing to secure a larger first-period market share. When product differentiation is also chosen endogenously, there continue to exist two asymmetric equilibria where one firm chooses more aggressive positioning. The more aggressive firm, whether through pricing or positioning, can force the game to be played to its advantage. But both firms end up worse off compared to when they use simpler pricing strategies or commit to substantial product differentiation. The online appendix is available at https://doi.org/10.1287/mnsc.2017.2873 . This paper was accepted by Juanjuan Zhang, marketing.