bluuebunny/crossref_metadata_2025_split huggingface dataset:
Mechanical Function of the Nucleus Pulposus of the Intervertebral Disc Under High Rates of Loading
Authors: Newell Nicolas , Carpanen Diagarajen , Evans John H. , Pearcy Mark J. , Masouros Spyros D. 
Published: May 2019

Study Design.
Bovine motion segments were used to investigate the high-rate compression response of intervertebral discs (IVD) before and after depressurising the nucleus pulposus (NP) by drilling a hole through the cranial endplate into it.

Objective.
To investigate the effect of depressurising the NP on the force–displacement response, and the energy absorption in IVDs when compressed at high strain rates.

Summary of Background Data.
The mechanical function of the gelatinous NP located in the center of the IVDs of the spine is unclear. Removal of the NP has been shown to affect the direction of bulge of the inner anulus fibrosus (AF), but at low loading rates removal of the NP pressure does not affect the IVD's stiffness. During sports or injurious events, IVDs are commonly exposed to high loading rates, however, no studies have investigated the mechanical function of the NP at these rates.

Methods.
Eight bovine motion segments were used to quantify the change in pressure caused by a hole drilled through the cranial endplate into the NP, and eight segments were used to investigate the high-rate response before and after a hole was drilled into the NP.

Results.
The hole caused a 28.5% drop in the NP pressure. No statistically significant difference was seen in peak force, peak displacement, or energy-absorption of the intact, and depressurized NP groups under impact loading. The IVDs absorbed 72% of the input energy, and there was no rate dependency in the percentage energy absorbed.

Conclusion.
These results demonstrate that the NP pressure does not affect the transfer of load through, or energy absorbed by, the IVD at high loading rates and the AF, rather than the NP, may play the most important role in transferring load, and absorbing energy at these rates. This should be considered when attempting surgically to restore IVD function.

Level of Evidence: N/A
Effect of Increasing Blood Pressure With Noradrenaline on the Microcirculation of Patients With Septic Shock and Previous Arterial Hypertension
Authors: Fiorese Coimbra Karla Tuanny , de Freitas Flávio Geraldo Rezende , Bafi Antônio Tonete , Pinheiro Tuanny Teixeira , Nunes Nathaly Fonseca , de Azevedo Luciano César Pontes , Machado Flávia Ribeiro 
Published: May 2019

Objectives:
To assess whether an increase in mean arterial pressure in patients with septic shock and previous systemic arterial hypertension changes microcirculatory and systemic hemodynamic variables compared with patients without arterial hypertension (control).

Design:
Prospective, nonblinded, interventional study.

Setting:
Three ICUs in two teaching hospitals.

Patients:
After informed consent, we included patients older than 18 years with septic shock for at least 6 hours, sedated, and under mechanical ventilation. We paired patients with and without arterial hypertension by age.

Interventions:
After obtaining systemic and microcirculation baseline hemodynamic variables (time 0), we increased noradrenaline dose to elevate mean arterial pressure up to 85–90 mm Hg before collecting a new set of measurements (time 1).

Measurements and Main Results:
We included 40 patients (20 in each group). There was no significant difference in age between the groups. After the rise in mean arterial pressure, there was a significant increase in cardiac index and a slight but significant reduction in lactate in both groups. We observed a significant improvement in the proportion of perfused vessels (control: 57.2 ± 14% to 66 ± 14.8%; arterial hypertension: 61.4 ± 12.3% to 70.8 ± 7.1%; groups: p = 0.29; T0 and T1: p < 0.001; group and time interaction: p = 0.85); perfused vessels density (control: 15.6 ± 4 mm/mm2 to 18.6 ± 4.5 mm/mm2; arterial hypertension: 16.4 ± 3.5 mm/mm2 to 19.1 ± 3 mm/mm2; groups: p = 0.51; T0 and T1: p < 0.001; group and time interaction: p = 0.70), and microcirculatory flow index (control: 2.1 ± 0.6 to 2.4 ± 0.6; arterial hypertension: 2.1 ± 0.5 to 2.6 ± 0.2; groups: p = 0.71; T0 and T1: p = 0.002; group and time interaction: p = 0.45) in both groups.

Conclusions:
Increasing mean arterial pressure with noradrenaline in septic shock patients improves density and flow in small vessels of sublingual microcirculation. However, this improvement occurs both in patients with previous arterial hypertension and in those without arterial hypertension.
Argon Inhalation for 24 Hours After Onset of Permanent Focal Cerebral Ischemia in Rats Provides Neuroprotection and Improves Neurologic Outcome
Authors: Ma Shuang , Chu Dongmei , Li Litao , Creed Jennifer A. , Ryang Yu-Mi , Sheng Huaxin , Yang Wei , Warner David S. , Turner Dennis A. , Hoffmann Ulrike 
Published: May 2019

Objectives:
We tested the hypothesis that prolonged inhalation of 70% argon for 24 hours after in vivo permanent or temporary stroke provides neuroprotection and improves neurologic outcome and overall recovery after 7 days.

Design:
Controlled, randomized, double-blinded laboratory study.

Setting:
Animal research laboratories.

Subjects:
Adult Wistar male rats (n = 110).

Interventions:
Rats were subjected to permanent or temporary focal cerebral ischemia via middle cerebral artery occlusion, followed by inhalation of 70% argon or nitrogen in 30% oxygen for 24 hours. On postoperative day 7, a 48-point neuroscore and histologic lesion size were assessed.

Measurements and Main Results:
After argon inhalation for 24 hours immediately following “severe permanent ischemia” induction, neurologic outcome (neuroscore, p = 0.034), overall recovery (body weight, p = 0.02), and infarct volume (total infarct volume, p = 0.0001; cortical infarct volume, p = 0.0003; subcortical infarct volume, p = 0.0001) were significantly improved. When 24-hour argon treatment was delayed for 2 hours after permanent stroke induction or until after postischemic reperfusion treatment, neurologic outcomes remained significantly improved (neuroscore, p = 0.043 and p = 0.014, respectively), as was overall recovery (body weight, p = 0.015), compared with nitrogen treatment. However, infarct volume and 7-day mortality were not significantly reduced when argon treatment was delayed.

Conclusions:
Neurologic outcome (neuroscore), overall recovery (body weight), and infarct volumes were significantly improved after 24-hour inhalation of 70% argon administered immediately after severe permanent stroke induction. Neurologic outcome and overall recovery were also significantly improved even when argon treatment was delayed for 2 hours or until after reperfusion.
Coexistence of Pemphigus Foliaceus and Grover Disease After a Radical Surgery for Basal Cell Carcinoma
Authors: Magdaleno-Tapial Jorge , Valenzuela-Oñate Cristian , Martínez-Doménech Álvaro , García-Legaz-Martínez Marta , Carballeira-Braña Alexo , Sánchez-Carazo José Luis , Pérez-Ferriols Amparo , Alegre-de Miquel Víctor 
Published: May 2019

Abstract:
The differential diagnosis of Grover disease (GD) includes pemphigus foliaceus. However, the focal nature of the histologic findings and negative direct immunofluorescent point to the diagnosis of GD. It has been associated with a variety of systemic and cutaneous diseases, but its association with other primary acantholytic disorders has been rarely documented. In this article, we describe the first case of GD in association with pemphigus foliaceus.
Drivers of Inpatient Costs After Colorectal Surgery Within a Publicly Funded Healthcare System
Authors: Springer Jeremy E. , Doumouras Aristithes G. , Saleh Fady , Lee Jennie , Amin Nalin , Cadeddu Margherita , Eskicioglu Cagla , Hong Dennis 
Published: May 2019

BACKGROUND:
The morbidity and mortality associated with colorectal resections are responsible for significant healthcare use. Identification of efficiencies is vital for decreasing healthcare cost in a resource-limited system.

OBJECTIVE:
The purpose of this study was to characterize the short-term cost associated with all colon and rectal resections.

DESIGN:
This was a population-based, retrospective administrative analysis.

SETTINGS:
This analysis was composed of all colon and rectal resections with anastomosis in Canada (excluding Quebec) between 2008 and 2015.

PATIENTS:
A total of 108,304 patients ≥18 years of age who underwent colon and/or rectal resections with anastomosis were included.

MAIN OUTCOME MEASURES:
Total short-term inpatient cost for the index admission and the incremental cost of each comorbidity and complication (in 2014 Canadian dollars) were measured. Cost predictors were modeled using hierarchical linear regression and Monte Carlo Markov Chain estimation.

RESULTS:
Multivariable regression demonstrated that the adjusted average cost of a 50-year–old man undergoing open colon resection for benign disease with no comorbidities or complications was $9270 ((95% CI, $7146–$11,624; p = <0.001). With adjustment for complications, laparoscopic colon resections carried a cost savings of $1390 (95% CI, $1682–$1099; p = <0.001) compared with open resections. Surgical complications were the main driver for increased cost, because anastomotic leaks added $9129 (95% CI, $8583–$9670; p = <0.001). Medical complications such as renal failure requiring dialysis ($16,939 (95% CI, $15,548–$18,314); p = <0.001) carried significant cost. Complications requiring reoperation cost $16,313 (95% CI, $15,739–$16,886; p = <0.001). The costliest complication cumulatively was reoperation, which exceeded $95 million dollars over the course of the study.

LIMITATIONS:
Inherent biases associated with administrative databases limited this study.

CONCLUSIONS:
Medical and surgical complications (especially those requiring reoperation) are major drivers of increased resource use. Laparoscopic colorectal resection with or without adjustment for complications carries a clear cost advantage. There is opportunity for considerable cost savings by reducing specific complications or by preoperatively optimizing select patients susceptible to costly complication. See Video Abstract at http://links.lww.com/DCR/A839.
Fecal Incontinence Symptoms and Impact in Older Versus Younger Women Seeking Care
Authors: Meyer Isuzu , Blanchard Christina T. , Markland Alayne D. , Gibson Elena G. , Richter Holly E. 
Published: May 2019

BACKGROUND:
The differential impact of aging on fecal incontinence symptom severity and condition-specific quality of life remains unclear.

OBJECTIVE:
The purpose of this study was to characterize differences in symptom distress, quality of life, and anorectal physiology assessments in older versus younger women with fecal incontinence.

DESIGN:
This was a cross-sectional study.

SETTINGS:
This study was conducted at a tertiary genitorectal disorder clinic.

PATIENTS:
Women presenting for fecal incontinence evaluation between 2003 and 2016 were classified as older or younger based on age ≥65 or <65 years.

MAIN OUTCOME MEASURES:
The main outcomes were symptom-specific quality of life and distress measured by validated questionnaires (the Modified Manchester Health Questionnaire containing the Fecal Incontinence Severity Index); anorectal physiology and anatomy were assessed by manometry and endoanal ultrasound.

RESULTS:
Of 879 subjects, 286 and 593 were classified as older and younger (mean ages, 71.4 ± 5.3 y and 51.3 ± 10.5 y). Solid stool leakage was more frequent in older women (83.2% vs 76.7%; p = 0.03), whereas liquid stool leakage (83.2% vs 82.8%; p = 0.88) and fecal urgency (76.9% vs 78.8%; p = 0.54) did not differ between groups. Mean symptom severity scores were similar between groups (28.0 ± 11.9 and 27.6 ± 13.5; p = 0.69); however, there was greater negative impact on quality of life among younger women (46.3 ± 22.0 vs 51.8 ± 21.8; p < 0.01). Multivariable linear regression controlling for pertinent covariates revealed younger age as an independent predictor for worse condition-specific quality-of-life scores (p < 0.01). Squeeze pressures were similar between groups, whereas younger women had greater resting pressures and higher rates of sphincter defects (external, 7.7% vs 20.2%; internal, 12.2% vs 26.8%; both p < 0.01).

LIMITATIONS:
This study was limited by its lack of patient obstetric history and the duration of their incontinence symptoms.

CONCLUSIONS:
Characteristics differ between older and younger women seeking care for fecal incontinence. The differential impact and age-related phenotypes may provide useful information for patient counseling and developing management algorithms for women with fecal incontinence. See Video Abstract at http://links.lww.com/DCR/A910.
Tacrolimus Can Be Reliably Measured With Volumetric Absorptive Capillary Microsampling Throughout the Dose Interval in Renal Transplant Recipients
Authors: Vethe Nils T. , Gustavsen Marte T. , Midtvedt Karsten , Lauritsen May E. , Andersen Anders M. , Åsberg Anders , Bergan Stein 
Published: May 2019

Background:
Therapeutic drug monitoring is standard practice for the immunosuppressant tacrolimus (Tac). Venous blood sampling at outpatient clinics is time-consuming and impractical with regard to obtaining trough concentrations on clinical visit days. Home-based blood sampling may be patient friendly and pave the way for limited sampling strategies for the prediction of total drug exposure. The aim was to establish a Tac assay for dried capillary microsamples, ensuring reliable measurements during the full dose interval in renal transplant recipients.

Methods:
An assay based on volumetric absorptive microsampling and liquid chromatography tandem mass spectrometry was validated. The agreement between capillary microsamples and liquid venous samples was investigated in stable renal recipients on twice-daily Tac dosing. Sampling throughout the 12-hour dose interval was examined at 2 separate days, at least 1 week apart, for each participant. Two sets of samples were obtained at each time point, one delivered directly to the laboratory and one sent through mail.

Results:
Twenty-seven renal transplant recipients were included, of whom 26 were investigated twice. Tac was efficiently extracted from the dried microsamples (mean recovery 94%–103%). The between-series mean accuracy was 88%–98% with coefficients of variation ≤5.0% (≤11% at the lower limit of quantification), measurement range 0.70–60 mcg/L. The mean difference between parallel microsamples was 5%–7%. Overall, the mean differences between dried microsamples and liquid samples were −3.1% when mailed (n = 679) and −4.2% when directly delivered (n = 682). Less than 8% were outside ±20%. The microsamples were stable for 1 month at ambient temperature.

Conclusions:
The microsample method demonstrated acceptable performance. Tac concentrations can be reliably quantified throughout the dose interval by using volumetric absorptive microsampling in renal transplant recipients, and the results are not influenced by postal shipment.
Disease-specific Preference-based Measure of Glaucoma Health States: HUG-5 Psychometric Validation
Authors: Kennedy Kevin , Podbielski Dominik , Nanji Keean , Muratov Sergei , Ahmed Ike , Xie Feng 
Published: May 2019

Purpose:
Glaucoma is the second leading cause of irreversible blindness in the world, with 60 million people worldwide estimated to suffer from the condition. Health utility is an important outcome measure of treatment effect in economic outcomes. The available tools for the measurement of health utility in glaucoma patients do not support a preference-based algorithm required to estimate health utility. To resolve this gap in the literature, the HUG-5 (Health Utility for Glaucoma—5 dimensions) was developed. The objective of the present study was to validate the HUG-5 with accepted measures of health state and vision-specific quality of life.

Materials and Methods:
The HUG-5 measures patient self-reported levels of visual discomfort, mobility, daily life activities, emotion, and social activities, as affected by the progression and management of glaucoma. To evaluate the psychometric properties, the HUG-5 was assessed for construct validity between similar and dissimilar dimensions of the National Eye Institute Visual Function Questionnaire-25 (NEI-VFQ-25) and the EuroQol’s 5 Dimensions. The HUG-5 was evaluated for test-retest reliability after a 2-week period. The HUG-5 composite distributions of mild/moderate and advanced glaucoma patients were tested for differences to measure sensitivity.

Results:
A total of 124 patients with glaucoma were administered the NEI-VFQ-25, the HUG-5, and the EuroQol’s 5 Dimensions. The HUG-5 demonstrated construct validity, with convergent and discriminant support for visual discomfort, mobility, daily life activities, emotional distress, and social activities. The HUG-5 concurrently measured health-related quality of life associated with best-eye visual field loss (r=0.63, P<0.001). The HUG-5 measured health state consistently with test-retest reliability (intraclass correlation=0.91, P<0.001). The HUG-5 was established to be sensitive in detecting differences between patients with mild/moderate glaucoma and those with advanced glaucoma with a rank-sum test with continuity correction (W=693.5, P<0.001).

Conclusions:
This study demonstrates promising results for the HUG-5’s response range and relationship with the NEI-VFQ-25 and best-eye visual field loss, highlighting the value of disease-specific preference-based scoring systems in measuring health state changes in glaucoma patients.
Evaluating the Laser Output of the Micropulse P3 Laser Delivery Device Following Repeated Use
Authors: Lun Katherine , Suwandono Maya E. , Koh Victor , Chew Paul T. 
Published: May 2019

Precis:
Repeated use of the Micropulse P3 (MP3) probe during micropulse transscleral cyclophotocoagulation is associated with an increase in laser output over time.

Purpose:
The purpose of this study was to examine the laser efficacy of the MP3 probe following repeated use.

Methods:
This was an observational study carried out using Cyclo G6 Glaucoma Laser System with 6 MP3 laser delivery probes. Each probe was fired for 100 seconds, every 10 minutes until the probe was deactivated. The laser output was measured using a laser power meter. Maximum observed laser power output was also noted.

Results:
All probes were deactivated after 90 minutes (9 cycles) of use. Mean laser output of all 6 probes was determined, and results suggested an increase in output with time. When examining the differences in total laser output for each cycle, no significant differences were observed for the first 4 cycles, but not for the remaining 5 cycles, wherein the increased laser outputs were found to be significantly different from baseline (cycle 1).

Conclusion:
Findings suggest a possible increase in laser output with repeated use, especially after 4 cycles, and clinicians need to be cautious if they intend to use the probes repeatedly.
Motor adaptation varies between individuals in the transition to sustained pain
Authors: Summers Simon J. , Chipchase Lucy S. , Hirata Rogerio , Graven-Nielsen Thomas , Cavaleri Rocco , Schabrun Siobhan M. 
Published: May 2019

Abstract
Musculoskeletal pain is associated with altered motor control that, despite short-term benefit, is hypothesised to have long-term consequences, contributing to the development of chronic pain. However, data on how motor control is altered when pain is sustained beyond a transient event are scarce. Here, we investigated motor adaptation, and its relationship with corticomotor excitability, in the transition to sustained muscle pain. Twenty-eight healthy individuals were injected with nerve growth factor into the right extensor carpi radialis brevis muscle on days 0 and 2. Motor adaptation and corticomotor excitability were assessed on day −2, before injection on days 0 and 2, and again on days 4 and 14. Motor adaptation was quantified during a radial–ulnar movement as kinematic variability of wrist flexion–extension and pronation–supination, and as electromyographic (EMG) variability of extensor carpi radialis brevis activity. Pain, muscle soreness, and functional limitation were assessed from days 0 to 14. Pain, muscle soreness, and functional limitation were evident at days 2 and 4 (P < 0.001). Electromyographic variability reduced at days 4 and 14 (P < 0.04), with no change in kinematic variability (P = 0.9). However, data revealed variation in EMG and kinematic variability between individuals: some displayed increased motor variability, whereas others a decrease. Individuals who displayed an increase in EMG variability after 4 days of pain also displayed an increase in corticomotor excitability (r = 0.43, P = 0.034). These findings suggest individual adaptation of the motor system in the transition to sustained pain that could have implications for clinical musculoskeletal pain disorders.
The Lived Experience of Antiretroviral Therapy for Pregnant Women: Antiretroviral Therapy Adherence as a Balancing Act
Authors: Shore Jessica E. , Paun Olimpia , Vonderheid Susan C. 
Published: May 2019

Abstract
We explored 10 pregnant women's experiences with antiretroviral therapy (ART) adherence using a qualitative approach. Semistructured interviews were conducted with pregnant ethnic minority women living with HIV and receiving integrated HIV/obstetric care at a Midwestern academic medical center in the United States. Data were analyzed using an interpretive phenomenology approach to identify major themes. We found an overarching theme: ART Adherence as a Balancing Act (striving to adhere to ART while having to simultaneously navigate daily challenges). We also identified four interrelated subthemes: struggles, support, motivators, and reminders. Findings highlight the need for clinicians to be sensitive to the emotional burdens of living with HIV while pregnant, a constant factor affecting quality of life and adherence. Having conversations about barriers and facilitators to adherence and encouraging women to identify strategies that support adherence are needed rather than focusing solely on pill counts and viral load.
Oral vs intravenous tranexamic acid in total-knee arthroplasty and total hip arthroplasty
Authors: Chen Xuanhuang , Zheng Feng , Zheng Zugao , Wu Xianwei , Wu Changfu 
Published: May 2019

Abstract

Background:
This study aimed to compare the efficacy and safety of oral tranexamic acid (TXA) with intravenous (IV) TXA in reducing perioperative blood loss in total-knee arthroplasty (TKA) and total-hip arthroplasty (THA).

Methods:
PubMed, Web of Science, Embase, and Cochrane Library were fully searched for relevant studies. Studies comparing the efficacy and safety of oral TXA with IV TXA in TKA and THA were included in this research. Odds ratio (OR) or risk difference (RD) was applied to compare dichotomous variables, while mean difference (MD) was used to compare continues variables.

Results:
A total of 7 studies (5 randomized controlled trials and 2 retrospective studies) were included into this study. As for patients undergoing TKA or THA, there were no obvious differences between oral TXA group and IV TXA group in hemoglobin (Hb) drop (MD = 0.06, 95% confidence interval [CI] = −0.01 to 0.13, P = .09), transfusion rate (OR = 0.78, 95% CI = 0.54–1.13, P = .19), total blood loss (MD = 16.31, 95% CI = −69.85 to 102.46, P = .71), total Hb loss (MD = 5.18, 95% CI = −12.65 to 23.02, P = .57), length of hospital stay (MD = -0.06, 95% CI = −0.30 to 0.18, P = .63), drain out (MD = 21.04, 95% CI = −15.81 to 57.88, P = .26), incidence of deep vein deep vein thrombosis (RD = 0.00, 95% CI = −0.01 to 0.01, P = .82) or pulmonary embolism (RD = 0.00, 95% CI = −0.01 to 0.01, P = .91). The sample size of this study was small and several included studies were with relatively low quality.

Conclusion:
Oral TXA is equivalent to IV TXA in reducing perioperative blood loss and should be recommended in TKA and THA. More high-quality studies are needed to elucidate this issue.