bluuebunny/crossref_metadata_2025_split huggingface dataset:
Functional Outcomes and Delayed Cerebral Ischemia Following Nonperimesencephalic Angiogram-Negative Subarachnoid Hemorrhage Similar to Aneurysmal Subarachnoid Hemorrhage
Authors: Al-Mufti Fawaz , Merkler Alexander E , Boehme Amelia K , Dancour Elie , May Theresa , Schmidt J Michael , Park Soojin , Connolly E Sander , Lavine Sean D , Meyers Philip M , Claassen Jan , Agarwal Sachin 
Published: May 2017

Abstract

BACKGROUND
The angiogram-negative subarachnoid hemorrhage (SAH) literature includes patients with perimesencephalic hemorrhage, which is recognized to have a much better outcome than aneurysmal SAH.

OBJECTIVE
To evaluate the clinical outcomes of Nonperimesencephalic Angiogram-Negative SAH (NPAN-SAH).

METHODS
A prospective, spontaneous SAH database of 1311 patients that accrued between April 2006 and December 2014 was screened. All patients with NPAN-SAH and 2 consecutive negative cerebral angiograms were included.

RESULTS
We identified 191 (11%) from a total of 1311 patients with spontaneous SAH. Amongst angiogram-negative patients, 83 (4.9%) were adjudicated to have NPAN-SAH. Patient characteristics were similar across the groups, except NPAN-SAH patients were more likely to be men and had higher rates of diabetes. In a multivariable logistic regression model, NPAN-SAH patients were less likely to develop vasospasm, after adjusting for Fisher grade, sex, and diabetes (odds ratio [OR]: 0.197, 95% confidence interval [CI; 0.07-0.55], P = .002). In another adjusted model accounting for Hunt and Hess clinical grade, NPAN-SAH patients were also less likely to develop vasospasm (OR: 0.2, 95% CI [0.07-0.57], P = .002). We found no statistical significance between 2 groups for rebleed, developing hydrocephalus, seizures, or delayed cerebral ischemia. NPAN-SAH patients were equally associated with poor functional outcome (modified Rankin scale ≥3; OR: 1.16, 95% CI [0.615-2.20], P = .6420), and death (OR: 1.22, 95% CI [0.362-4.132], P = .7455) compared to aneurysmal SAH.

CONCLUSION
Although the risk of vasospasm may be lower, patients with NPAN-SAH are equally associated with delayed cerebral ischemia, poor outcome, and death as compared to patients with aneurysmal SAH. Furthers studies may be necessary to further clarify these findings
Size is the Most Important Predictor of Aneurysm Rupture Among Multiple Cerebral Aneurysms: Post Hoc Subgroup Analysis of Unruptured Cerebral Aneurysm Study Japan
Authors: Shojima Masaaki , Morita Akio , Nakatomi Hirofumi , Tominari Shinjiro 
Published: May 2017

Abstract

BACKGROUND
Multiple cerebral aneurysms are encountered in approximately 15% to 35% of patients harboring unruptured cerebral aneurysms. It would be of clinical value to determine which of them is most likely to rupture.

OBJECTIVE
To characterize features of the ruptured aneurysm relative to other concomitant fellow aneurysms in patients with multiple cerebral aneurysms.

METHODS
From a total of 5720 patients who were prospectively registered in the Unruptured Cerebral Aneurysm Study in Japan, a subgroup of patients with multiple cerebral aneurysms who developed subarachnoid hemorrhage was extracted for this post hoc analysis. Intrapatient comparisons of each aneurysm were carried out using aneurysm-specific factors such as size, location, and shape to identify predictors of rupture among the fellow aneurysms in a patient with multiple cerebral aneurysms.

RESULTS
Twenty-five patients with 62 aneurysms were identified from the total cohort of 5720 patients. With the distinctiveness in size, which means the aneurysm was the single largest among the multiple aneurysms, the ruptured aneurysm in each case was discriminated from the other coexisting aneurysms with a sensitivity of 0.76 and specificity of 0.86.

CONCLUSION
Our results suggest that the largest aneurysm is likely to rupture among coexisting aneurysms in a patient with multiple cerebral aneurysms.
False-Positive and False-Negative Results of Motor Evoked Potential Monitoring During Surgery for Intramedullary Spinal Cord Tumors
Authors: Kurokawa Ryu , Kim Phyo , Itoki Kazushige , Yamamoto Shinji , Shingo Tetsuro , Kawamoto Toshiki , Kawamoto Shunsuke 
Published: May 2017

Abstract

BACKGROUND
Motor evoked potential (MEP) recording is used as a method to monitor integrity of the motor system during surgery for intramedullary tumors (IMTs). Reliable sensitivity of the monitoring in predicting functional deterioration has been reported. However, we observed false positives and false negatives in our experience of 250 surgeries of IMTs.

OBJECTIVE
To delineate specificity and sensitivity of MEP monitoring and to elucidate its limitations and usefulness.

METHODS
From 2008 to 2011, 58 patients underwent 62 surgeries for IMTs. MEP monitoring was performed in 59 operations using transcranial electrical stimulation. Correlation with changes in muscle strength and locomotion was analyzed. A group undergoing clipping for unruptured aneurysms was compared for elicitation of MEP.

RESULTS
Of 212 muscles monitored in the 59 operations, MEP was recorded in 150 (71%). Positive MEP warnings, defined as amplitude decrease below 20% of the initial level, occurred in 37 muscles, but 22 of these (59%) did not have postoperative weakness (false positive). Positive predictive value was limited to 0.41. Of 113 muscles with no MEP warnings, 8 muscles developed postoperative weakness (false negative, 7%). Negative predictive value was 0.93. MEP responses were not elicited in 58 muscles (27%). By contrast, during clipping for unruptured aneurysms, MEP was recorded in 216 of 222 muscles (96%).

CONCLUSION
MEP monitoring has a limitation in predicting postoperative weakness in surgery for IMTs. False-positive and false-negative indices were abundant, with sensitivity and specificity of 0.65 and 0.83 in predicting postoperative weakness.
MITSuME observation of V404 Cygni in the 2015 outburst: Two optical variable components with different variability
Authors: Tachibana Yutaro , Yoshii Taketoshi , Hanayama Hidekazu , Kawai Nobuyuki 
Published: May 2017

Abstract
The black hole binary V404 Cygni (= GS 2023+338) had an outburst on 2015 June 15 after 26 years of its quiescence. We report on the multi-color optical observation (g΄, RC, and IC) of this object at the beginning of its outburst performed by the MITSuME 50 cm telescope in Akeno, Yamanashi, and the MURIKABUSHI 105 cm telescope at Ishigakijima Astronomical Observatory. Through time domain analysis of the multi-color light curves, we successfully decomposed the optical variations into two components: a highly variable and a less-variable component. The loci of the less-variable component in the color–color diagram are consistent with that of multi-temperature blackbody radiation, while those of the highly variable component trace out a power-law spectrum with a spectral index α ∼ 0.6–1.0. For the less-variable component, we argue that an irradiated disk with the innermost temperature higher than ∼2.0 × 104 K and the outermost temperature lower than ∼6.5 × 103 K is the most plausible source. The gradual rising trend of the light curve during our observation is probably due to the growing of the less-variable component. The observed spectral energy distribution from optical to ultraviolet can be expressed by a model consisting of a power-law component and an irradiated disk component.
Length of Stay, Mortality, Cost, and Perceptions of Care Associated With Transition From an Open to Closed Staffing Model in the Cardiac Intensive Care Unit
Authors: Katz Jason N. , Lishmanov Anton , van Diepen Sean , Yu Dongqing , Shen Haipeng , Pauley Eric , Bhatia Jatin , Buntaine Adam , Das Arun , Dangerfield Cristie , McLaughlin Brooke , Stouffer George A. , Kaul Prashant 
Published: May 2017

Background:
Organizational models in the intensive care unit (ICU) have classically been described as either closed or open, depending on the presence or absence of a dedicated ICU team. Although a closed model has been shown to improve patient outcomes in medical and surgical ICUs, the merits of various care models have not been previously explored in the cardiac ICU (CICU) setting.

Methods:
From November 2012 to March 2014, data were prospectively collected on all admissions before and after transition from an open to closed CICU at our institution. Baseline clinical variables, illness severity, admission and discharge diagnoses, resource use, and outcomes were recorded. Anonymous surveys were also collected from nursing and resident trainee participants to evaluate the influence of unit structure on perceptions of care. Descriptive statistics were used, and logistic regression modeling was performed to examine the impact of unit structure on mortality.

Results:
The study consisted of 670 patients, 332 (49.6%) of whom were admitted to the open CICU model and 338 (50.4%) of whom were admitted to the closed model. Neither CICU nor hospital mortality differed between the open and closed units, though length of stay was shorter in the closed CICU. Additionally, nurses and resident trainees reported that the closed CICU allowed for better communication, collaboration, and education.

Conclusions:
Although there was no significant impact of unit structure on patient outcomes in this single-center study, the closed CICU model was associated with better perceptions of care.
Effectiveness of 2-hour Troponin in High-risk Patients With Suspected Acute Coronary Syndrome
Authors: Bove Joseph , Hochman Steven , Miller Jacob , Artim Stephen 
Published: May 2017

Background:
Research has shown the safety and effectiveness of drawing a standard troponin level at presentation and again at 2 hours in only low-risk patients. Because high-sensitivity troponins are not currently approved in the United States, we studied the utility of a standard troponin that is presently in use. Our goal was to determine if 2-hour standard troponin would be safe and effective in the evaluation of a high-risk cohort of patients never studied previously.

Methods:
We conducted a single-center prospective observational study of adult patients presenting to the emergency department with signs and symptoms suggestive of acute coronary syndrome. Patients were defined as high risk if the attending physician planned to admit or transfer the patient to the observation unit. History, Electrocardiography, Age, Risk factors, Troponin scores were calculated on all patients to provide verification that the individuals were high risk. The primary outcome was a composite of 30-day myocardial infarction, death, cardiac arrest with return of spontaneous circulation, or dysrhythmia. The secondary outcome was 30-day revascularization.

Results:
We included a total of 122 patients with an average follow-up of 112 days (minimum 30 days). A total of 86% of cases had History, Electrocardiography, Age, Risk factors, Troponin scores ≥4. The primary outcome was met in 22 (18%) patients, and the secondary outcome occurred in 7 (5.7%) patients. The negative predictive value of negative 2-hour troponins along with no significant delta troponin rise was 98.7%.

Conclusions:
Discharging patients thought to be high risk who have negative troponins at 0 and 2 hours and no delta troponin rise appears safe. No deaths occurred in follow-up. Larger studies are warranted.
Understanding Women's Sexual Behaviors That May Put Them at Risk for Human Papillomavirus–Related Neoplasias: What Should We Ask?
Authors: Kulkarni Amita , Tran Tram , Luis Christine , Raker Christina A. , Cronin Beth , Robison Katina 
Published: May 2017

Objectives
Human papillomavirus is a multifocal infection that can involve the cervix, vagina, vulva, anus, and oropharynx. Our study aimed to determine whether standard sexual history questions regarding anal intercourse identify women participating in anal-related sexual practices.

Materials and Methods
A cross-sectional survey was conducted at the dysplasia clinic of a large academic medical center. Women presenting with human papillomavirus–related cervical, vulvar, or vaginal abnormalities were eligible. Participants completed a self-administered sexual history questionnaire that included standard sexual history questions and more detailed questions about sexual practices. Additional demographic information was obtained from chart review.

Results
A total of 149 eligible women were approached, 125 (84%) consented and enrolled (ages = 21–65 years). Forty-seven (44%) reported participating in some type of anal-related sexual practice: anal fingering, oral-anal penetration, or anal intercourse. Of those participating in anal-related practices, 5 (11%) reported only anal fingering or oral-anal penetration. Thus, adding the new anal questions detected an additional 5% of women with high-risk anal behaviors that may have been missed by the standard question (p = .06). Seventy-nine women (63%) reported receiving oral penetration of the vagina, and 102 (82%) reported receiving vaginal fingering. Fifty-nine women (47%) used sex toys: 58 (98%) used sex toys vaginally, with 5 (8.5%) using them also anally.

Conclusions
Women are willing to report their participation in a range of sexual practices. Of those who participated in anal practices, 11% did not have anal intercourse. Adding additional sexual health questions to clinical intake forms may enable clinicians to better counsel their patients on risky sexual behaviors.
Ultrasound-guided pericardiocentesis: a novel parasternal approach
Authors: Osman Adi , Wan Chuan Tan , Ab Rahman Jamalludin , Via Gabriele , Tavazzi Guido 
Published: May 2017

Objective
The aim of this study was to evaluate a novel pericardiocentesis technique using an in-plane parasternal medial-to-lateral approach with the use of a high-frequency probe in patients with cardiac tamponade.

Background
Echocardiography is pivotal in the diagnosis of pericardial effusion and tamponade physiology. Ultrasound guidance for pericardiocentesis is currently considered the standard of care. Several approaches have been described recently, which differ mainly on the site of puncture (subxiphoid, apical, or parasternal). Although they share the use of low-frequency probes, there is absence of complete control of needle trajectory and real-time needle visualization. An in-plane and real-time technique has only been described anecdotally.

Methods and results
A retrospective analysis of 11 patients (63% men, mean age: 37.7±21.2 years) presenting with cardiac tamponade admitted to the tertiary-care emergency department and treated with parasternal medial-to-lateral in-plane pericardiocentesis was carried out. The underlying causes of cardiac tamponade were different among the population. All the pericardiocentesis were successfully performed in the emergency department, without complications, relieving the hemodynamic instability. The mean time taken to perform the eight-step procedure was 309±76.4 s, with no procedure-related complications.

Conclusion
The parasternal medial-to-lateral in-plane pericardiocentesis is a new technique theoretically free of complications and it enables real-time monitoring of needle trajectory. For the first time, a pericardiocentesis approach with a medial-to-lateral needle trajectory and real-time, in-plane, needle visualization was performed in a tamponade patient population.
The Development of the Chinese Intermittent Exotropia Questionnaire
Authors: Zhu Hui , Shen Ling , Yuan Chao-Qun , Xu Shu , Leng Zhen-Hua , Fu Zhu-Jun , Xiao Yun-Hua , Liu Hu 
Published: May 2017

ABSTRACT

Purpose
The Intermittent Exotropia Questionnaire (IXTQ) is a child, proxy, and parent report of health-related quality of life specific to children with intermittent exotropia (IXT). The present study aimed to develop a Chinese-language version of the IXTQ (CIXTQ) and evaluate its validity and reliability when used in Chinese IXT children and their parents.

Methods
The IXTQ was translated into Chinese. One hundred seventy-five IXT children (2 to 17 years old) and 151 orthotropic control children (2 to 17 years old) along with one of their parents were recruited. Children 5 to 17 years old completed the 5- to 7-year-old or the 8- to 17-year-old child questionnaire of the CIXTQ according to their age. Parents of all children (2 to 17 years old) completed the proxy and parent questionnaires of the CIXTQ. Psychometric properties of the CIXTQ were examined for floor and ceiling effects, construct validity, item-internal consistency, discriminative validity, Cronbach α coefficient and test-retest reliability.

Results
No items were found to have strong floor or ceiling effects. Principal component analysis identified that the CIXTQ had a similar structure to the original English version. The median scores of each questionnaire in the CIXTQ among children with IXT and their parents were significantly lower than those among control subjects (P < .001). Cronbach α coefficients ranged from 0.869 to 0.931, and test-retest reliabilities ranged from 0.898 to 0.981, for each questionnaire in the CIXTQ.

Conclusions
The CIXTQ is a useful tool to evaluate the influence of IXT on health-related quality of life among Chinese IXT children and their parents.
Foveal Curvature and Asymmetry Assessed Using Optical Coherence Tomography
Authors: VanNasdale Dean A. , Eilerman Amanda , Zimmerman Aaron , Lai Nicky , Ramsey Keith , Sinnott Loraine T. 
Published: May 2017

ABSTRACT

Purpose
The aims of this study were to use cross-sectional optical coherence tomography imaging and custom curve fitting software to evaluate and model the foveal curvature as a spherical surface and to compare the radius of curvature in the horizontal and vertical meridians and test the sensitivity of this technique to anticipated meridional differences.

Methods
Six 30-degree foveal-centered radial optical coherence tomography cross-section scans were acquired in the right eye of 20 clinically normal subjects. Cross sections were manually segmented, and custom curve fitting software was used to determine foveal pit radius of curvature using the central 500, 1000, and 1500 μm of the foveal contour. Radius of curvature was compared across different fitting distances. Root mean square error was used to determine goodness of fit. The radius of curvature was compared between the horizontal and vertical meridians for each fitting distance.

Results
There radius of curvature was significantly different when comparing each of the three fitting distances (P < .01 for each comparison). The average radii of curvature were 970 μm (95% confidence interval [CI], 913 to 1028 μm), 1386 μm (95% CI, 1339 to 1439 μm), and 2121 μm (95% CI, 2066 to 2183) for the 500-, 1000-, and 1500-μm fitting distances, respectively. Root mean square error was also significantly different when comparing each fitting distance (P < .01 for each comparison). The average root mean square errors were 2.48 μm (95% CI, 2.41 to 2.53 μm), 6.22 μm (95% CI, 5.77 to 6.60 μm), and 13.82 μm (95% CI, 12.93 to 14.58 μm) for the 500-, 1000-, and 1500-μm fitting distances, respectively. The radius of curvature between the horizontal and vertical meridian radii was statistically different only in the 1000- and 1500-μm fitting distances (P < .01 for each), with the horizontal meridian being flatter than the vertical.

Conclusions
The foveal contour can be modeled as a sphere with low curve fitting error over a limited distance and capable of detecting subtle foveal contour differences between meridians.
Alloimmunity But Not Viral Immunity Promotes Allograft Loss in a Mouse Model of Polyomavirus-Associated Allograft Injury
Authors: Kim Steven C. , Wang Jun , Dong Ying , Mathews David V. , Albrecht Joshua A. , Breeden Cynthia P. , Farris Alton B. , Lukacher Aron E. , Ford Mandy L. , Newell Kenneth A. , Adams Andrew B. 
Published: May 2017

Background
The interplay between viral infection and alloimmunity is known to influence the fate of transplanted organs. Clarifying how local virus-associated inflammation/injury and antiviral immunity can alter host alloimmune responses in transplantation remains a critical question.

Methods
We used a mouse model of polyomavirus (PyV) infection and kidney transplantation to investigate the roles of direct viral pathology, the antiviral immune response, and alloimmunity in the pathogenesis of PyV-associated allograft injury. We have previously shown that an effective primary T cell response is required in PyV-associated graft injury.

Results
Here we show that the transfer of primed antidonor, but not antiviral, T cells results in PyV-associated allograft injury. In further studies, we use a surrogate minor antigen model (ovalbumin) and show that only antidonor specific T cells and not antiviral specific T cells are sufficient to mediate injury. Lastly, we demonstrate that local but not systemic virus-mediated inflammation and injury within the graft itself are required.

Conclusions
These data suggest that in this mouse model, the predominant mechanism of allograft injury in PyV-associated injury is due to an augmented alloimmune T cell response driven by virus-induced inflammation/injury within the graft. These studies highlight the important interplay between viral infection and alloimmunity in a model system.
Clustering: how much bias do we need?
Authors: Lorimer Tom , Held Jenny , Stoop Ruedi 
Published: May 2017

Scientific investigations in medicine and beyond increasingly require observations to be described by more features than can be simultaneously visualized. Simply reducing the dimensionality by projections destroys essential relationships in the data. Similarly, traditional clustering algorithms introduce data bias that prevents detection of natural structures expected from generic nonlinear processes. We examine how these problems can best be addressed, where in particular we focus on two recent clustering approaches, Phenograph and Hebbian learning clustering, applied to synthetic and natural data examples. Our results reveal that already for very basic questions, minimizing clustering bias is essential, but that results can benefit further from biased post-processing.
This article is part of the themed issue ‘Mathematical methods in medicine: neuroscience, cardiology and pathology’.
Are Your Covariates Under Control? How Normalization Can Re-introduce Covariate Effects
Authors: Pain Oliver , Dudbridge Frank , Ronald Angelica 
Published: May 2017

AbstractMany statistical tests rely on the assumption that the residuals of a model are normally distributed. Rank-based inverse normal transformation (INT) of the dependent variable is one of the most popular approaches to satisfy the normality assumption. Studies regularly adjust for covariates and then normalize the residuals. This study investigated the effect of regressing covariates against the dependent variable and then applying rank-based INT to the residuals. The correlation between the dependent variable and covariates at each stage of processing was assessed. An alternative approach was tested of applying rank-based INT to the dependent variablebeforeregressing covariates was tested. Analyses based on both simulated and real data examples demonstrated that applying rank-based INT to the dependent variable residuals after regressing out covariates re-introduces a linear correlation between the dependent variable and covariates in almost all situations. This will increase type-1 errors and reduce power. Our proposed alternative approach, where rank-based INT was applied prior to controlling for covariate effects, gave residuals that were normally distributed and linearly uncorrelated with covariates. This approach is therefore recommended.