bluuebunny/crossref_metadata_2025_split huggingface dataset:
Two mechanisms for dust gap opening in protoplanetary discs
Authors: Dipierro Giovanni , Laibe Guillaume , Price Daniel J. , Lodato Giuseppe 
Published: March 2016

Abstract
We identify two distinct physical mechanisms for dust gap opening by embedded planets in protoplanetary discs based on the symmetry of the drag-induced motion around the planet: (I) a mechanism where low-mass planets, that do not disturb the gas, open gaps in dust by tidal torques assisted by drag in the inner disc, but resisted by drag in the outer disc; and (II) the usual, drag-assisted, mechanism where higher mass planets create pressure maxima in the gas disc, which the drag torque then acts to evacuate further in the dust. The first mechanism produces gaps in dust but not gas, while the second produces partial or total gas gaps which are deeper in the dust phase. Dust gaps do not necessarily indicate gas gaps.
Burnout and Alcohol Abuse/Dependence Among U.S. Medical Students
Authors: Jackson Eric R. , Shanafelt Tait D. , Hasan Omar , Satele Daniel V. , Dyrbye Liselotte N. 
Published: March 2016

Purpose
To explore the relationship between alcohol abuse/dependence with burnout and other forms of distress among a national cohort of medical students.

Method
In 2012, the authors completed a national survey of medical students from the American Medical Association’s Physician Masterfile containing validated items assessing alcohol abuse/dependence, burnout, depression, suicidality, quality of life (QOL), and fatigue. Descriptive and comparative statistical analyses were computed, including chi-square and multivariate logistic regression, to determine relationships between variables.

Results
Of the 12,500 students, 4,402 (35.2%) responded. Of these, 1,411 (32.4%) met diagnostic criteria for alcohol abuse/dependence. Students who were burned out (P = .01), depressed (P = .01), or reported low mental (P =.03) or emotional (P = .016) QOL were more likely to have alcohol abuse/dependence. Emotional exhaustion and depersonalization domains of burnout were strongly associated with alcohol abuse/dependence. On multivariate analysis, burnout (OR 1.20; 95% CI 1.05–1.37; P < .01), having $50,000 to $100,000 (OR 1.21 versus < $50,000; CI 1.02–1.44; P < .05) or > $100,000 (OR 1.27 versus < $50,000; CI 1.08–1.48; P < .01) of educational debt, being unmarried (OR 1.89; CI 1.57–2.27; P < .001), and being younger (for every five years, OR 1.15; CI 1.02–1.28; P = .01) were independently associated with increased risk for alcohol abuse/dependence.

Conclusions
Burnout was strongly related to alcohol abuse/dependence among sampled medical students and increased educational debt predicted a higher risk. A multifaceted approach addressing burnout, medical education costs, and alcohol use is needed.
Adductor Canal Block Provides Noninferior Analgesia and Superior Quadriceps Strength Compared with Femoral Nerve Block in Anterior Cruciate Ligament Reconstruction
Authors: Abdallah Faraj W. , Whelan Daniel B. , Chan Vincent W. , Prasad Govindarajulu A. , Endersby Ryan V. , Theodoropolous John , Oldfield Stephanie , Oh Justin , Brull Richard 
Published: March 2016

AbstractAbstract
In a randomized trial of 100 subjects undergoing anterior cruciate ligament, analgesia from adductor canal block was not inferior to that of femoral nerve block, but quadriceps muscle strength was superior.

Background
By targeting the distal branches of the femoral nerve in the mid-thigh, the adductor canal block (ACB) can preserve quadriceps muscle strength while providing analgesia similar to a conventional femoral nerve block (FNB) for inpatients undergoing major knee surgery. In this randomized, double-blind, noninferiority trial, the authors hypothesized that ACB provides postoperative analgesia that is at least as good as FNB while preserving quadriceps strength after outpatient anterior cruciate ligament reconstruction.

Methods
A total of 100 patients were randomized to receive ACB or FNB with 20 ml ropivacaine 0.5% (with epinephrine). The authors sequentially tested the joint hypothesis that ACB is noninferior to FNB for cumulative oral morphine equivalent consumption and area under the curve for pain scores during the first 24 h postoperatively and also superior to FNB for postblock quadriceps maximal voluntary isometric contraction.

Results
The authors analyzed 52 and 48 patients who received ACB and FNB, respectively. Compared with preset noninferiority margins, the ACB–FNB difference (95% CI) in morphine consumption and area under the curve for pain scores were −4.8 mg (−12.3 to 2.7) (P = 0.03) and −71 mm h (−148 to 6) (P < 0.00001), respectively, indicating noninferiority of ACB for both outcomes. The maximal voluntary isometric contraction for ACB and FNB at 45 min were 26.6 pound-force (24.7–28.6) and 10.6 pound-force (8.3–13.0) (P < 0.00001), respectively, indicating superiority of ACB.

Conclusion
Compared with FNB, the study findings suggest that ACB preserves quadriceps strength and provides noninferior postoperative analgesia for outpatients undergoing anterior cruciate ligament reconstruction.
Infusion System Architecture Impacts the Ability of Intensive Care Nurses to Maintain Hemodynamic Stability in a Living Swine Simulator
Authors: Pezone Matthew J. , Peterfreund Robert A. , Maslov Mikhail Y. , Govindaswamy Radhika R. , Lovich Mark A. 
Published: March 2016

AbstractAbstract
We investigated the ability of skilled intensive care unit registered nurses to overcome pharmacologic delays caused by large infusion system common volumes in a swine model. The data suggest that smaller common volume leads to better hemodynamic control.

Background
The authors have previously shown that drug infusion systems with large common volumes exhibit long delays in reaching steady-state drug delivery and pharmacodynamic effects compared with smaller common-volume systems. The authors hypothesized that such delays can impede the pharmacologic restoration of hemodynamic stability.

Methods
The authors created a living swine simulator of hemodynamic instability in which occlusion balloons in the aorta and inferior vena cava (IVC) were used to manipulate blood pressure. Experienced intensive care unit nurses blinded to the use of small or large common-volume infusion systems were instructed to maintain mean arterial blood pressure between 70 and 90 mmHg using only sodium nitroprusside and norepinephrine infusions. Four conditions (IVC or aortic occlusions and small or large common volume) were tested 12 times in eight animals.

Results
After aortic occlusion, the time to restore mean arterial pressure to range (t
1: 2.4 ± 1.4 vs. 5.0 ± 2.3 min, P = 0.003, average ± SD), time-out-of-range (t
OR: 6.2 ± 3.5 vs. 9.5 ± 3.4 min, P = 0.028), and area-out-of-range (pressure–time integral: 84 ± 47 vs. 170 ± 100 mmHg·min, P = 0.018) were all lower with smaller common volumes. After IVC occlusion, t
1 (3.7 ± 2.2 vs. 7.1 ± 2.6 min, P = 0.002), t
OR (6.3 ± 3.5 vs. 11 ± 3.0 min, P = 0.007), and area-out-of-range (110 ± 93 vs. 270 ± 140 mmHg·min, P = 0.003) were all lower with smaller common volumes. Common-volume size did not impact the total amount infused of either drug.

Conclusions
Nurses did not respond as effectively to hemodynamic instability when drugs flowed through large common-volume infusion systems. These findings suggest that drug infusion system common volume may have clinical impact, should be minimized to the greatest extent possible, and warrants clinical investigations.
Iron Parameters Determine the Prognosis of Critically Ill Patients*
Authors: Tacke Frank , Nuraldeen Renwar , Koch Alexander , Strathmann Klaus , Hutschenreuter Gabriele , Trautwein Christian , Strnad Pavel 
Published: March 2016

Objective:
Because iron is both an essential and toxic micronutrient influencing the development of microbial infections, we evaluated the usefulness of iron parameters as outcome predictors in ICU patients.

Design:
Prospective clinical single-center non-interventional study.

Setting:
General internal medicine ICU; German University hospital.

Patients:
One hundred and twelve septic and 43 nonseptic ICU patients, 156 healthy blood donors.

Measurements and Main Results:
Serum iron parameters at admission were correlated with short and long term mortality in ICU subjects. Both hepcidin and ferritin concentrations were significantly elevated in ICU patients compared with blood donors and were the highest in septic patients. On the contrary, serum iron and transferrin levels were decreased in ICU subjects with lowest values among septic patients. Hepcidin values correlated with ferritin levels, and serum iron correlated strongly with transferrin saturation. A moderate correlation of hepcidin, ferritin, and transferrin with inflammatory parameters was noted. Both short- and long-term survivors displayed higher ferritin/transferrin levels and lower transferrin saturation. In Kaplan-Meier analyses, low iron levels (cutoff 10.5 μmol/mL), low transferrin saturation (cutoff 55%), and high serum transferrin concentrations (cutoff 1.6 g/L) were associated with short- and long-term survival. In the subgroup of septic ICU subjects, low iron levels and transferrin saturation went along with a nonlethal outcome.

Conclusions:
Our findings demonstrate that parameters of iron metabolism, particularly transferrin saturation, that reflect serum iron availability, are strong outcome predictors in ICU patients. These data suggest that a failure of iron homeostasis with increased iron availability in serum occurs in lethally ill ICU patients and should trigger prospective clinical trials evaluating the usefulness of iron-chelating therapy in critical illness and sepsis.
Adjuvant Corticosteroid Treatment in Adults With Influenza A (H7N9) Viral Pneumonia*
Authors: Cao Bin , Gao Hainv , Zhou Boping , Deng Xilong , Hu Chengping , Deng Chaosheng , Lu Hongzhou , Li Yuping , Gan Jianhe , Liu Jingyuan , Li Hui , Zhang Yao , Yang Yida , Fang Qiang , Shen Yinzhong , Gu Qin , Zhou Xianmei , Zhao Wei , Pu Zenghui , Chen Ling , Sun Baoxia , Liu Xi , Hamilton Carol Dukes , Li Lanjuan 
Published: March 2016

Objective:
To determine the impact of adjuvant corticosteroids administered to patients hospitalized with influenza A (H7N9) viral pneumonia.

Design:
The effects of adjuvant corticosteroids on mortality were assessed using multivariate Cox regression and a propensity score-matched case-control study. Nosocomial infections and viral shedding were also compared.

Setting:
Hospitals with influenza A (H7N9) viral pneumonia patient admission in 84 cities and 16 provinces of Mainland China.

Patients:
Adolescent and Adult patients aged >14 yr with severe laboratory-confirmed influenza A (H7N9) virus infections were screened from April 2013 to March 2015.

Interventions:
None.

Measurements and Main Results:
The study population comprised 288 cases who were hospitalized with influenza A (H7N9) viral pneumonia. The median age of the study population was 58 years, 69.8% of the cohort comprised male patients, and 51.4% had at least one type of underlying diseases. The in-hospital mortality was 31.9%. Two hundred and four patients (70.8%) received adjuvant corticosteroids; among them, 193 had hypoxemia and lung infiltrates, 11 had chronic obstructive pulmonary disease, and 11 had pneumonia only. Corticosteroids were initiated within 7 days (interquartile range, 5.0–9.4 d) of the onset of illness and the maximum dose administered was equivalent to 80-mg methylprednisolone (interquartile range, 40–120 mg). The patients were treated with corticosteroids for a median duration of 7 days (interquartile range, 4.0–11.3 d). Cox regression analysis showed that compared with the patients who did not receive corticosteroid, those who received corticosteroid had a significantly higher 60-day mortality (adjusted hazards ratio, 1.98; 95% CI, 1.03–3.79; p = 0.04). Subgroup analysis showed that high-dose corticosteroid therapy (> 150 mg/d methylprednisolone or equivalent) significantly increased both 30-day and 60-day mortality, whereas no significant impact was observed for low-to-moderate doses of corticosteroids (25–150 mg/d methylprednisolone or equivalent). The propensity score–matched case-control analysis showed that the median viral shedding time was much longer in the group that received high-dose corticosteroids (15 d), compared with patients who did not receive corticosteroids (13 d; p = 0.039).

Conclusions:
High-dose corticosteroids were associated with increased mortality and longer viral shedding in patients with influenza A (H7N9) viral pneumonia.
Comparison of Population Pharmacokinetics Based on Steady-State Assumption Versus Electronically Monitored Adherence to Lopinavir, Atazanavir, Efavirenz, and Etravirine: A Retrospective Study
Authors: Fuchs Aline , Rotzinger Aurélie , Cavassini Matthias , Bugnon Olivier , Buclin Thierry , Schneider Marie Paule , Csajka Chantal 
Published: March 2016

Background:
Population pharmacokinetic (PopPK) analyses often rely on steady state and full adherence to prescribed dosage regimen assumptions from data gathered during therapeutic drug monitoring (TDM). Nonadherence is common in chronic diseases such as HIV. This study evaluates the impact of adherence measurement by electronic monitoring on PopPK parameter estimation and individual concentration profile predictions, and also the influence of adherence issues on the clinical interpretation of a concentration measurement.

Methods:
Published PopPK models for lopinavir, atazanavir, efavirenz, and etravirine were applied to estimate PK parameters and individual concentrations in 140 HIV patients taking part in a medication adherence program using 2 dosing data sets. The first set included the last dose reported by the patient with steady-state and full adherence assumptions; the second set used detailed electronic dosing history. PopPK parameter estimates and individual predictions were compared between the 2 dosing entries.

Results:
Clearance estimates and likewise predicted concentrations did not markedly differ between the 2 dosing histories. However, certain patterns of nonadherence such as sparse missed doses or consecutive missed doses lead to suboptimal drug exposure. The interpretation based on self-reported information would have concluded on a wrongly appropriate individual exposure.

Conclusions:
PopPK analysis assuming steady state with full adherence produced similar results to those based on detailed electronic dosing history reconciled with patients' allegations. Self-reported last dose intake appeared reliable for concentration predictions and therapeutic drug monitoring interpretation for most patients followed at the medication adherence program. Yet, clinicians should be aware that concentration predictions based on self-reported last dose intake might be overestimated in case of undetected patterns of nonadherence, increasing the risk of forthcoming therapeutic failure.
CENTRAL SEROUS CHORIORETINOPATHY IN POSTMENOPAUSAL WOMEN RECEIVING EXOGENOUS TESTOSTERONE
Authors: Conway Mandi D. , Noble Jason A. , Peyman Gholam A. 
Published: March 2016

Purpose:
Central serous chorioretinopathy (CSR) is a serous detachment of the neurosensory retina commonly associated with male sex, Type-A personality and corticosteroid use. Exogenous administration of androgens and development of CSR in men has been reported. Only one case of CSR in a postmenopausal woman receiving exogenous androgen therapy has been reported. The authors describe three cases of chronic CSR in postmenopausal women receiving exogenous testosterone therapy.

Methods:
Diagnosis was based on characteristic clinical, fluorescein angiographic, and optical coherence tomography findings. The three women were being treated with exogenous testosterone and progesterone therapy for symptoms of menopause and libido loss.

Results:
Average age at presentation was 54.7 years (53–56 years), average duration of exogenous androgen use was 61 months (36–87 months), with average 19.7-month follow-up. Resolution of symptoms seemed correlated with cessation of androgen use despite treatment with oscillatory photodynamic therapy and intravitreal pharmacotherapy with antivascular endothelial growth factor agents.

Conclusion:
Exogenous testosterone is increasingly prescribed for menopausal symptoms and libido loss. Treatment with oscillatory photodynamic therapy, supplemental bevacizumab intravitreal pharmacotherapy, and cessation of exogenous androgen therapy was successful in three cases of chronic, therapy-resistant CSR. Ophthalmologists should inquire about androgen usage in patients who present with CSR, especially in the setting of therapy resistance.
Predictors of fecal transplant failure
Authors: Meighani Alireza , Hart Benjamin R. , Mittal Chetan , Miller Nichole , John Ajin , Ramesh Mayur 
Published: March 2016

Background

Clostridium difficile infection (CDI) is a significant healthcare burden, with increased morbidity and mortality. Traditional treatment regimens using antibiotics for recurrent CDI are significantly less successful compared with 80–90% with fecal microbiota transplantation (FMT). There is a paucity of data on failure rates and mortality after FMT in CDI. This study aims to identify the rates of failure, relapse, and mortality associated with FMT as well as the risk factors for FMT failure.

Methods
A large retrospective cohort study was carried out including all patients who underwent FMT from December 2012 through May 2014. Patient factors (demographics, comorbidities, immune-suppression, transplant history, antibiotics used, hospitalization, and surgeries), disease factors (number of episodes of CDI, treatments, and severity), and transplant factors (route and number of FMT) were examined. Failure of treatment was defined as no resolution of diarrhea in patients who had been treated with one or more fecal microbiota transplantation within 90 days of FMT.

Results
A total of 201 patients (age 66.6±18.3 years, 62.2% women) were included. The overall failure rate was 12.4%. Patients with failed fecal transplant had increased number of FMTs compared with those who responded (mean 1.92±0.997 vs. 1.29±0.615; P=0.004). No colectomies or death related to CDI were found in our patient population. Significant predictors of failure were female sex (P=0.016), previous hospitalization (P=0.006), and surgery before FMT (P=0.005). The overall mortality rate was 9.0% and failure of FMT was associated with an increased risk of death (odds ratio=5.833, confidence interval 2.01–16.925; P<0.05).

Conclusion
FMT is a suitable alterative to antibiotic use for recurrent CDIs, with a high success rate. The results indicate that hospital-acquired CDI may be a predictor of failure of FMT.
General Anesthesia in a Patient With Urticaria Pigmentosa Referred for Electroconvulsive Therapy
Authors: Aloysi Amy S. , Ahle Gabriella M. , Geduldig Emma , Kellner Charles H. , Bryson Ethan O. 
Published: March 2016

Abstract
Urticaria pigmentosa is a rare disorder characterized by an abnormal systemic proliferation of mast cells. In this condition, various triggers can induce either cutaneous histamine release, resulting in rash, or generalized histamine release, resulting in symptomatic hypotension, syncope, or in its severest form, an anaphylactoid reaction resistant to most resuscitative measures. Many anesthetic agents and adjuncts are known potential triggers, and patients who require surgery or procedures under anesthesia must be managed carefully. In this review, we describe the safe use of general anesthesia for electroconvulsive therapy in a patient with urticaria pigmentosa and discuss the association between psychiatric disorders and mastocytoses.
Assessing the Effects of Repetitive Transcranial Magnetic Stimulation on Cognition in Major Depressive Disorder Using Computerized Cognitive Testing
Authors: Galletly Cherrie , Gill Shane , Rigby Ashlee , Carnell Benjamin Luke , Clarke Patrick 
Published: March 2016

Objectives
A range of different treatment approaches are available for depression; however, there is an ongoing concern about the cognitive impairment associated with many treatments. This study investigated the effect of treatment with repetitive transcranial magnetic stimulation (rTMS) on cognition in patients with major depressive disorder. Cognition before and after treatment was assessed using a computerized cognitive testing battery, which provided comprehensive assessment across a range of cognitive domains. This was a naturalistic study involving patients attending an outpatient clinical rTMS service.

Methods
A total of 63 patients with treatment-resistant depression completed the IntegNeuro cognitive test battery, a well-validated comprehensive computerized assessment tool before and after receiving 18 or 20 treatments of sequential bilateral rTMS. Change in the various cognitive domains was assessed, and analyses were undertaken to determine whether any change in cognition was associated with a change in rating of depression severity.

Results
There was a significant decrease in Hamilton Depression Rating Scale scores from baseline to posttreatment. There was no decline in performance on any of the cognitive tests. There were significant improvements in maze completion time and the number of errors in the maze task. However, these were accounted for by improvement in mood when change in depressive symptoms was included as a covariate.

Conclusions
This open-label study provides further support for the efficacy and safety of rTMS as a treatment option for people with major depressive disorder in a naturalistic clinical setting. Using a comprehensive, robust computerized battery of cognitive tests, the current study indicated that there was no significant cognitive impairment associated with rTMS and that any improvements in cognitive functioning were associated with a reduction in depressive symptoms.