bluuebunny/crossref_metadata_2025_split huggingface dataset:
Can online social support be detrimental in stigmatized chronic diseases? A quadratic model of the effects of informational and emotional support on self-care behavior of HIV patients
Authors: Wang Xunyi , Parameswaran Srikanth , Bagul Darshan Mahendra , Kishore Rajiv 
Published: February 2018

Abstract

Objective
We studied the impact of online social support on patient self-care behavior in an online health community for human immunodeficiency virus (HIV) patients. We conceptualized emotional and informational support provided by community members into nuanced sub-dimensions. We explored how the direct and interaction effects of these sub-dimensions impact the self-care behavior of a support seeker.

Methods
We used data from 330 255 posts in 30 050 threads from POZ, an online health community for HIV patients. Our key variables—self-care behaviori, objective informationj, experiential supportj, and emotional tonej—were operationalized using linguistic analysis with self-generated dictionaries and Python libraries. We tested our hypotheses using Tobit regression.

Results
Out of 6 null hypotheses, 5 were rejected. Objective information and emotional tone had an inverted-U relationship with self-care behavior. Experiential information and community involvement were positively related to self-care behavior. Community involvement amplified the inverted-U relationship between emotional tone and self-care behavior. No significant interaction effect was found between experiential support and objective information.

Conclusions
Beyond a threshold, both informational and emotional online social support had a deleterious impact on self-care behavior of HIV patients. Our results suggested that caution should be exercised in the use of online health community interventions for HIV patients, and perhaps patients with other stigmatized chronic diseases.
Identification of Global and Local Shocks in International Financial Markets via General Dynamic Factor Models*
Authors: Barigozzi Matteo , Hallin Marc , Soccorsi Stefano 
Published: February 2018

AbstractWe employ a two-stage general dynamic factor model to analyze co-movements between returns and between volatilities of stocks from the U.S., European, and Japanese financial markets. We find two common shocks driving the dynamics of volatilities—one global shock and one United States–European shock—and four local shocks driving returns, but no global one. Co-movements in returns and volatilities increased considerably in the period 2007–2012 associated with the Great Financial Crisis and the European Sovereign Debt Crisis. We interpret this finding as the sign of a surge, during crises, of interdependencies across markets, as opposed to contagion. Finally, we introduce a new method for structural analysis in general dynamic factor models which is applied to the identification of volatility shocks via natural timing assumptions. The global shock has homogeneous dynamic effects within each individual market but more heterogeneous effects across them, and is useful for predicting aggregate realized volatilities.
Cleaved β-Actin May Contribute to DNA Fragmentation Following Very Brief Focal Cerebral Ischemia
Authors: Ye Zhouheng , Ander Bradley P , Sharp Frank R , Zhan Xinhua 
Published: February 2018

Abstract
Our previous study demonstrated caspase independent DNA fragmentation after very brief cerebral ischemia, the mechanism of which was unclear. In this study, we explore whether actin is cleaved following focal cerebral ischemia, and whether these structural changes of actin might modulate DNA fragmentation observed following focal ischemia. Results showed that a cleaved β-actin fragment was identified in brains of rats 24 hours following 10-minute and 2-hour focal ischemia. Though granzyme B and caspase-3 cleaved β-actin in vitro, the fragment size of β-actin cleaved by granzyme B was the same as those found after 10-minute and 2-hour focal ischemia. This was consistent with increases of granzyme B activity after 10-minute and 2-hour ischemia compared with controls. Cerebral extracts from 10-minute and 2-hour ischemic brains degraded DNA in vitro. Adding intact β-actin to these samples completely abolished DNA degradation from the 10-minute ischemia group but not from the 2-hour ischemia group. We concluded that β-actin is likely cleaved by granzyme B by 24 hours following 10-minute and 2-hour focal cerebral ischemia. Intact β-actin inhibits DNase, and cleavage of β-actin activates DNase, which leads to DNA fragmentation observed in the brain following very brief focal ischemia.
Vision loss in glioblastoma: Disease mimicking presumed therapeutic toxicity
Authors: Nguyen HuyTram N , Vo Kevin B H , Howard Steven , Salamat M Shahriar , Rowely Howard , Robins H Ian 
Published: February 2018

Abstract
Glioblastoma is the most common and lethal form of primary brain cancer. In the recurrent setting, bevacizumab is a common choice for salvage therapy. Loss of vision in patients initially treated with radiation at the time of diagnosis and later treated with bevacizumab at time of recurrence has been reported, and presumed to be a treatment-related optic neuropathy. Strikingly, only 1 case report described a postmortem biopsy to rule out tumor involvement of the optic tracts. We report the first case of recurrent glioblastoma infiltrating the prechiasmatic and chiasmatic optic nerve, which at the time of vision loss was presumed to be secondary to bevacizumab. It is noteworthy that the MRI findings in the previously reported bevacizumab/radiation-induced optic neuropathy cases (without pathology follow-up) are comparable to our patient.
HIV-1 Drug Resistance and Third-Line Therapy Outcomes in Patients Failing Second-Line Therapy in Zimbabwe
Authors: Chimbetete Cleophas , Katzenstein David , Shamu Tinei , Spoerri Adrian , Estill Janne , Egger Matthias , Keiser Olivia 
Published: February 2018

Abstract

Objectives
To analyze the patterns and risk factors of HIV drug resistance mutations among patients failing second-line treatment and to describe early treatment responses to recommended third-line antiretroviral therapy (ART) in a national referral HIV clinic in Zimbabwe.

Methods
Patients on boosted protease inhibitor (PI) regimens for more than 6 months with treatment failure confirmed by 2 viral load (VL) tests &gt;1000 copies/mL were genotyped, and susceptibility to available antiretroviral drugs was estimated by the Stanford HIVdb program. Risk factors for major PI resistance were assessed by logistic regression. Third-line treatment was provided as Darunavir/r, Raltegravir, or Dolutegravir and Zidovudine, Abacavir Lamivudine, or Tenofovir.

Results
Genotypes were performed on 86 patients who had good adherence to treatment. The median duration of first- and second-line ART was 3.8 years (interquartile range [IQR], 2.3–5.1) and 2.6 years (IQR, 1.6–4.9), respectively. The median HIV viral load and CD4 cell count were 65 210 copies/mL (IQR, 8728–208 920 copies/mL) and 201 cells/mm3 (IQR, 49–333 cells/mm3). Major PI resistance-associated mutations (RAMs) were demonstrated in 44 (51%) non-nucleoside reverse transcriptase inhibitor RAMs in 72 patients (83%) and nucleoside reverse transcriptase inhibitors RAMs in 62 patients (72%). PI resistance was associated with age &gt;24 years (P = .003) and CD4 cell count &lt;200 cells/mm3 (P = .007). In multivariable analysis, only age &gt;24 years was significantly associated (adjusted odds ratio, 4.75; 95% confidence interval, 1.69–13.38; P = .003) with major PI mutations. Third-line DRV/r- and InSTI-based therapy achieved virologic suppression in 29/36 patients (81%) after 6 months.

Conclusions
The prevelance of PI mutations was high. Adolescents and young adults had a lower risk of acquiring major PI resistance mutations, possibly due to poor adherence to ART. Third-line treatment with a regimen of Darunavir/r, Raltegravir/Dolutegravir, and optimized nucleoside reverse transcriptase inhibitors was effective.
Detailed CO(J = 1–0, 2–1, and 3–2) observations toward an H ii region RCW 32 in the Vela Molecular Ridge
Authors: Enokiya Rei , Sano Hidetoshi , Hayashi Katsuhiro , Tachihara Kengo , Torii Kazufumi , Yamamoto Hiroaki , Hattori Yusuke , Hasegawa Yutaka , Ohama Akio , Kimura Kimihiro , Ogawa Hideo , Fukui Yasuo 
Published: February 2018

Abstract
We performed CO(J = 1–0, 2–1, and 3–2) observations toward an H ii region RCW 32 in the Vela Molecular Ridge. The CO gas distribution associated with the H ii region was revealed for the first time at a high resolution of 22″. The results revealed three distinct velocity components which show correspondence with the optical dark lanes and/or Hα distribution. Two of the components show complementary spatial distribution which suggests collisional interaction between them at a relative velocity of ∼ 4 km s−1. Based on these results, we present a hypothesis that a cloud–cloud collision determined the cloud distribution and triggered formation of the exciting star ionizing RCW 32. The collision time scale is estimated from the cloud size and the velocity separation to be ∼2 Myr and the collision terminated ∼1 Myr ago, which is consistent with the age of the exciting star and the associated cluster. By combing the previous works on the H ii regions in the Vela Molecular Ridge, we argue that the majority (at least four) of the H ii regions in the Ridge were formed by triggering of cloud–cloud collision.
The Geography of NGO Activism against Multinational Corporations
Authors: Hatte Sophie , Koenig Pamina 
Published: February 2018

AbstractTo what extent do Non-Governmental Organizations (NGOs) monitor global value chains? While NGOs regularly denounce the behavior of multinational corporations throughout the world, their motivations for choosing campaign targets remain largely unknown. Using a new dataset on activists’ campaigns toward multinational firms, we estimate a triadic gravity equation for campaigns, involving the NGO, firm, and action countries. Our results point to a strong proximity bias in NGO activity: Distance, national borders, and lack of a common language all contribute to impede the intensity of campaigns. We estimate the distance elasticity of campaigns to be −0.2 and further document that NGOs strongly bias their actions toward home firms or foreign firms with home actions. A domestic firm is 3.45 times more likely to be attacked than a foreign one. Foreign firms headquartered in common language countries draw 1.63 times more campaigns. Overall, campaigns seem to be designed so as to include at least one element of proximity drawing the attention of consumers. This pattern questions the role of NGOs in the monitoring of multinational production operated in remote, unfamiliar locations.
Buprenorphine Depresses Respiratory Variability in Obese Mice with Altered Leptin Signaling
Authors: Angel Chelsea , Glovak Zachary T. , Alami Wateen , Mihalko Sara , Price Josh , Jiang Yandong , Baghdoyan Helen A. , Lydic Ralph 
Published: February 2018

Abstract

Background
Opiate-induced respiratory depression is sexually dimorphic and associated with increased risk among the obese. The mechanisms underlying these associations are unknown. The present study evaluated the two-tailed hypothesis that sex, leptin status, and obesity modulate buprenorphine-induced changes in breathing.

Methods
Mice (n = 40 male and 40 female) comprising four congenic lines that differ in leptin signaling and body weight were injected with saline and buprenorphine (0.3 mg/kg). Whole-body plethysmography was used to quantify the effects on minute ventilation. The data were evaluated using three-way analysis of variance, regression, and Poincaré analyses.

Results
Relative to B6 mice with normal leptin, buprenorphine decreased minute ventilation in mice with diet-induced obesity (37.2%; P < 0.0001), ob/ob mice that lack leptin (62.6%; P < 0.0001), and db/db mice with dysfunctional leptin receptors (65.9%; P < 0.0001). Poincaré analyses showed that buprenorphine caused a significant (P < 0.0001) collapse in minute ventilation variability that was greatest in mice with leptin dysfunction. There was no significant effect of sex or body weight on minute ventilation.

Conclusions
The results support the interpretation that leptin status but not body weight or sex contributed to the buprenorphine-induced decrease in minute ventilation. Poincaré plots illustrate that the buprenorphine-induced decrease in minute ventilation variability was greatest in mice with impaired leptin signaling. This is relevant because normal respiratory variability is essential for martialing a compensatory response to ventilatory challenges imposed by disease, obesity, and surgical stress.
Nail Fit: Does Nail Diameter to Canal Ratio Predict the Need for Exchange Nailing in the Setting of Aseptic, Hypertrophic Femoral Nonunions?
Authors: Millar Michael J. , Wilkinson Andrew , Navarre Pierre , Steiner Joel , Vohora Ashray , Hardidge Andrew , Edwards Elton 
Published: February 2018

Objectives:
To evaluate patient-independent risk factors for aseptic femoral hypertrophic nonunion requiring exchange nailing, with particular reference to the fit of the nail at the isthmus within the canal.

Design:
Retrospective case control study.

Setting:
Level 1 trauma center.

Main Outcome Measurements:
Between 2008 and 2012, 211 patients without any patient-dependent risk factors for nonunion were treated with a locked reamed intramedullary nail for a femoral shaft fracture. Twenty-three cases went on to hypertrophic nonunion requiring exchange nailing (treatment group) and 188 cases went on to union (control group). Patient-independent risk factors for exchange nailing were documented.

Results:
Patient-independent risk factors for exchange nailing were poor fracture reduction [Odds ratio (OR): 11.5, 95% confidence interval (CI), 4.0–33.4, P < 0.001], open fracture (OR: 7.6, 95% CI, 3.0–19.6, P = 0.004), Winquist classification of 4 (OR: 4.4, 95% CI, 1.9–6.7, P = 0.016), and poor nail fit (OR: 10.3, 95% CI, 5.1–28.4, P < 0.001). Multivariate analysis revealed nail fit as an independent predictor of femoral nonunion requiring exchange nailing (OR: 11.4, 95% CI, 6.9–15.2, P < 0.001). Moreover, we found a direct relationship between increasingly poor nail fit and increased risk of exchange nailing, with the criterion occurring at a nail fit ratio <70%.

Conclusion:
When proceeding to femoral fracture reamed intramedullary nailing, we recommend a minimum nail fit of 70% at the isthmus and ideally 90% or more, to avoid surgical reintervention.

Level of Evidence:
Prognostic Level III. See Instructions for Authors for a complete description of levels of evidence.
Intraoperative Vancomycin Powder Reduces Staphylococcus aureus Surgical Site Infections and Biofilm Formation on Fixation Implants in a Rabbit Model
Authors: Hovis James Paul , Montalvo Ryan , Marinos Dimitrius , Joshi Manjari , Shirtliff Mark E. , O'Toole Robert V. , Manson Theodore T. 
Published: February 2018

Objectives:
To evaluate the effectiveness of intraoperative vancomycin powder in prevention of surgical site infection and biofilm formation on implants in a contaminated animal fixation model.

Methods:
We created a rabbit surgical model including fixation implants at a tibial surgical site seeded with methicillin-resistant Staphylococcus aureus. Our study cohort included 18 rabbits. Nine received vancomycin powder at the surgical site, and the other 9 did not. Serum vancomycin levels were measured at scheduled time points over 24 hours. Bone infection and implant biofilm formation were determined based on the number of colony-forming units present 2 weeks after surgery. Radiography, histology, and electron microscopy aided in evaluation.

Results:
No bone infection or implant colonization occurred in the vancomycin powder group. Six bone infections and 6 implant biofilm formations (67%; 95% confidence interval, 45%–88%) occurred in the group that did not receive vancomycin powder (P = 0.009). Serum vancomycin levels were detectable at minimal levels at 1 and 6 hours only. Pathological changes occurred in the specimens that were positive for infection.

Conclusions:
Intraoperative vancomycin powder application at the time of fixation decreases risk for bone infection and biofilm formation on implants in a rabbit model, with minimal increase in serum vancomycin levels. The results are encouraging and support the rationale for a clinical trial investigating the use of local vancomycin powder to reduce the rate of surgical site infections.

Clinical Relevance:
Infection is a common complication of surgery, especially with implants. Simple methods to prevent or decrease the occurrence of infection would benefit the patient and the health care system.
What Is the Ideal Starting Point for an Olecranon Screw? An Anatomic Cadaveric Study
Authors: Potter G. David , Mascarenhas Daniel , Sciadini Marcus F. , Carlini Anthony R. , O'Toole Robert V. , Pensy Raymond A. 
Published: February 2018

Objective:
To assess whether “center-center” position is ideal starting point for minimum fracture displacement when placing an intramedullary (IM) screw in the ulna.

Methods:
Thirty-six arms (average age, 82 years) underwent a posterior approach to the olecranon and were randomized into 3 groups: center-center (center in sagittal plane, center in coronal plane), posterior-lateral (posterior in sagittal plane, lateral in coronal plane), and posterior-medial (posterior in sagittal plane, medial in coronal plane). Groups were matched into 18 pairs, and fixation was performed with an IM screw. Primary outcome measure was articular surface displacement on the olecranon. Measurements were compared across each combination of locations using the Kruskal-Wallis rank sums test, and a sign test determined whether each location differed from anatomic reduction.

Results:
Articular step-off measurements were significantly different between center-center (0.6 mm) and posterior-medial (2.1 mm) groups (P = 0.01) and approached significance with posterior-lateral versus posterior-medial (0.9 mm) locations (P = 0.07). No significant difference was found comparing center-center with posterior-lateral locations (P = 0.7). The articular surface (P = 0.04), posterior cortex (P = 0.02), and medial cortex (P = 0.001) measurements for the posterior-medial starting point were all worse compared with anatomic reduction.

Conclusions:
Malreduction of a simulated olecranon fracture was most significant when the starting point for the IM screw was malpositioned medially. A central or laterally based starting point was more forgiving. Avoiding a medially based starting point is crucial for achieving benefits of fixation with an IM screw and reduces the chance of malreduction after fixation.
The Economic Burden of Musculoskeletal Disease in Children and Adolescents in the United States
Authors: Rosenfeld Scott B. , Schroeder Katherine , Watkins-Castillo Sylvia I. 
Published: February 2018

Background:
Musculoskeletal conditions are among the most common and costly conditions suffered by Americans. In 2011, there was an estimated $213 billion in annual cost of direct treatment for and lost wages due to musculoskeletal disease in the United States. Data on economic burden, however, comes mostly from the adult population, with significantly less information regarding the burden of these conditions in young patients available. The purpose of this report is to provide data on the economic burden of musculoskeletal diseases in children and adolescents in the United States.

Methods:
Eleven diagnosis categories were identified, with health care visits and hospitalization data derived from ICD-9-CM codes for each of the conditions searched. The largest database utilized was the Healthcare Cost and Utilization Project (HCUP) Kids’ Inpatient Database (KID). Total visits came from the KID, HCUP NEDS (emergency department), NCHS NHAMCS OP (outpatient), and NCHS NAMCS (physician office) databases. The National Health Interview Survey (NHIS) child sample was additionally searched to obtain patient/parent-reported data.

Results:
In 2012, more than 19 million children and adolescents received treatment in medical centers, physicians’ offices, and hospitals for a musculoskeletal-related condition. The most common reason for treatment (68%) was traumatic injury, followed by a pain syndrome (13%) and deformity (9%). Total hospital charges in 2012 for children and adolescents with a primary musculoskeletal-related diagnosis totaled $7.6 billion. Trauma (43%) and deformity (38%) were the major contributors to total hospital charges.

Conclusions:
Although we found that hospital-related charges for musculoskeletal diseases for children and adolescents in 2012 totaled $7.6 billion, this number underestimates the total cost for all pediatric musculoskeletal conditions. Musculoskeletal conditions accounted for 5.4% of hospital charges in the pediatric population. However, only 1.4% of pediatric research funding is designated to musculoskeletal research. Going forward, the data in this report may be used to further research and to stimulate development of better methods with which to measure the direct and indirect costs of musculoskeletal conditions in children.

Level of Evidence:
Level IV—economic and decision analysis.
Neurovascular Changes Associated With the Water Drinking Test
Authors: Gameiro Gustavo , Monsalve Pedro , Golubev Iuri , Ventura Lori , Porciatti Vittorio 
Published: February 2018

Purpose:
The water drinking test (WDT) is currently used to temporarily elevate intraocular pressure (IOP) and predict peak IOP in glaucoma. This study investigates neurovascular changes associated with WDT in normal subjects.

Methods:
The effect of WDT (1 L in 5 min) on IOP, mean brachial blood pressure, heart rate, and pattern electroretinogram was assessed within the next hour in 16 healthy subjects (mean age: 33.5±7.9 y). As a control, testing was repeated in the same subjects without WDT 1 week later.

Results:
Compared with control, WDT resulted in significant peak changes of the following parameters compared with baseline: IOP: +1.7±1.8 mm Hg after 30′, mean brachial blood pressure: +3.9±6.3 mm Hg after 15′; heart rate: −9.2±9.8 bpm after 15′, pattern electroretinogram latency: +2.1±0.9 ms after 15′.

Conclusions:
In addition to IOP elevation, WDT was associated with significant changes of hemodynamic parameters and retinal ganglion cell function in young healthy subjects. As these represent risk factors for glaucoma, their assessment upon WDT might increase its predictive power for glaucoma development.