bluuebunny/crossref_metadata_2025 huggingface dataset:
How complex is the cosmic web?
Authors: Vazza F
Published: November 2019

The growth of large-scale cosmic structure is a beautiful exemplification of how complexity can emerge in our Universe, starting from simple initial conditions and simple physical laws. Using enzo cosmological numerical simulations, I applied tools from Information Theory (namely, ‘statistical complexity’) to quantify the amount of complexity in the simulated cosmic volume, as a function of cosmic epoch and environment. This analysis can quantify how much difficult to predict, at least in a statistical sense, is the evolution of the thermal, kinetic, and magnetic energy of the dominant component of ordinary matter in the Universe (the intragalactic medium plasma). The most complex environment in the simulated cosmic web is generally found to be the periphery of large-scale structures (e.g. galaxy clusters and filaments), where the complexity is on average ∼10–102 times larger than in more rarefied regions, even if the latter dominate the volume-integrated complexity of the simulated Universe. If the energy evolution of gas in the cosmic web is measured on a ≈100 ${\rm kpc}\, h^{-1}$ resolution and over a ≈200 $\rm Myr$ time-scale, its total complexity is in the range of $\sim 10^{16}\!-\!10^{17} \rm \,bits$, with little dependence on the assumed gas physics, cosmology, or cosmic variance.
Single-atom Sn-Zn pairs in CuO catalyst promote dimethyldichlorosilane synthesis
Authors: Shi Qi , Ji Yongjun , Chen Wenxin , Zhu Yongxia , Li Jing , Liu Hezhi , Li Zhi , Tian Shubo , Wang Ligen , Zhong Ziyi , Wang Limin , Ma Jianmin , Li Yadong , Su Fabing
Published: November 2019

Single-atom catalysts are of great interest because they can maximize the atom-utilization efficiency and generate unique catalytic properties; however, much attention has been paid to single-site active components, rarely to catalyst promoters. Promoters can significantly affect the activity and selectivity of a catalyst, even at their low concentrations in catalysts. In this work, we designed and synthesized CuO catalysts with atomically dispersed co-promoters of Sn and Zn. When used as the catalyst in the Rochow reaction for the synthesis of dimethyldichlorosilane, this catalyst exhibited much-enhanced activity, selectivity and stability compared with the conventional CuO catalysts with promoters in the form of nanoparticles. Density functional theory calculations demonstrate that single-atomic Sn substitution in the CuO surface can enrich surface Cu vacancies and promote dispersion of Zn to its atomic levels. Sn and Zn single sites as the co-promoters cooperatively generate electronic interaction with the CuO support, which further facilitates the adsorption of the reactant molecules on the surface, thereby leading to the superior catalytic performance.
Slavery in Medieval Europe
Authors: Barker Hannah
Published: November 2019

Common knowledge would have it that slavery did not exist in medieval Europe. However, there is a thriving body of scholarship which demonstrates that slavery was practiced widely in various forms in Europe during the Middle Ages, alongside captivity, serfdom, and other types of unfreedom. Where then did the common knowledge come from? In the first instance, it derives from the late-18th- and 19th-century abolitionist assumption that as Christianity spread through Europe during the Middle Ages, it must surely have driven out slavery. Among scholars, this common knowledge is sometimes reinforced by Marxist historical narratives, according to which slavery was the mode of production characteristic of the Roman period, while serfdom characterized the medieval period. Yet into the 14th and 15th centuries, medieval Europeans continued to own slaves, trade in slaves, and enslave each other as well as non-European others. They used slaves for agricultural and artisanal labor as well as domestic, sexual, reproductive, and military service. However, the composition of enslaved populations, their demographic and social significance in relation to free populations, the precise legal meaning of slave status, and the practices associated with slavery all varied significantly by region and era. Though Europe was not the only slave-holding region during the medieval period, scholarship about the history of slavery in medieval Byzantium, the Islamic world, Central Asia, East Asia, South Asia, Africa, and the Americas is substantial. Each of these regions merits a bibliography of its own. Moreover, though slavery was not the only form of unfreedom that existed in medieval Europe, captives, hostages, prisoners, and pledges have also been the subjects of much research and merit dedicated bibliographies, too. Finally, though the academic study of medieval slavery came into being in the 19th century alongside the abolitionist discourse that ignored its existence, this bibliography will highlight recent works, especially those produced within the last fifty years. Many older works remain useful as reference points and guides to the archival sources, but contemporary scholars have brought fresh analytical perspectives to bear on slavery studies, each contributing to the flourishing field that exists today.
Paris
Authors: Lyon-Caen Nicolas
Published: November 2019

From the 13th century until the early 18th century, Paris—the capital city of France and the official residence of the kings—was the largest city in Europe. Many scholars have provided in-depth studies on the urban life and the ordinary life of the Parisians, at city-wide or district level. But the metropolis also played a prominent political, cultural, and economic role, both for the kingdom and for the rest of the world. Therefore, the history of the city as a civic community is inextricably interwoven with the history of the French state. Historians have usually stressed the limitations the state imposed on the city’s autonomy. But at the same time, Parisian elites are often considered as the main agent of centralization. Yet when it comes to describing what the consequences are of the special position of Paris, scholars differ on what the pertinent scale of analysis should be. They also disagree on issues pertaining to the link between the growing prominence of Paris and the national government: to what extent was it determined by the city’s own importance rather than by a process of centralization? By embracing the notion of capital city, many historians endeavor to articulate both the global and the local scales of the metropolis.
Margaret Walker
Authors: Byerman Keith
Published: November 2019

Margaret Abigail Walker Alexander was born in Birmingham, Alabama, on July 7, 1915. Her father, Sigismund, was a Methodist minister born in Jamaica and educated at Northwestern University; her mother, Marion Dozier, a music teacher. Both later taught at New Orleans University. In 1925, they moved to New Orleans and lived with Walker’s maternal grandmother, Elvira “Vyry” Dozier, who provided many of the stories used in her only novel, Jubilee (1966). After two years at New Orleans University (now Dillard University) Walker received her bachelor’s degree from Northwestern University in 1935. She then worked in Chicago for the Federal Writers’ Project and became part of what came to be known as the black Chicago renaissance, often associated with the novelist Richard Wright. Her friendship with him ended acrimoniously after he moved to New York. She continued to help him with the research for his celebrated novel Native Son (1940) after he left Chicago. She earned her master’s degree at the University of Iowa, with the poetry collection that was published as For My People, which won the Yale Younger Poets Award (1942). She married Firnist James Alexander in 1943, and they had four children. She taught at Livingstone College and West Virginia State College before moving to a permanent position at Jackson State University, where she taught from 1949 to 1979. In 1962, she took leave from her teaching position to work on a doctorate at Iowa. Her dissertation was based on the stories told by her grandmother and on the research she had conducted in the South for thirty years. She earned her degree in 1965 and the novel was published a year later as Jubilee. During this time, she continued writing poetry, including Ballad of the Free (1966)—a chapbook—and Prophets for a New Day (1970), both of which concern the civil rights movement, and October Journey (1973), primarily a collection of celebrations of black historical and literary figures, including a long memorial to her father. At Jackson State in 1968, she established the Institute for the Study of the History, Life, and Culture of Black People. In 1973, she organized the Phillis Wheatley Poetry Festival through the Institute; it brought together twenty African American women poets of different generations. For Folkways Records in 1975, she recorded three albums of poetry by African American artists, including her own version of “Yalluh Hammuh,” which she had collected as part of the Federal Writers Project. In 1989, she published This is My Century: New and Collected Poems. Her most controversial work is Richard Wright: Daemonic Genius (1987), which many reviewers have seen as an attack on her former friend, even though she adds significant detail to his early career in Chicago. She died of cancer on November 30, 1998.
Alliance Portfolios
Authors: Soh Pek-Hooi , Subramanian Annapoornima M.
Published: November 2019

The field of alliance portfolio research has grown significantly since 2007, and much research has focused on the impact of alliance portfolios on firm performance. An alliance portfolio is a collection of alliances established by a firm with different partners over a certain number of years. The term has also been referred to as a network of direct ties or bilateral relationships of the firm. In management research, some researchers use the term to account for all alliances that remain actively involved in focal firm’s business when assessing the competitive positioning of the firm in an industry, whereas others include both existing and past alliances when focal firm’s alliance experience and capability development is concerned. In strategic management and innovation studies, scholars have investigated alliance portfolios that are typically made up of a variety of strategic partners who may possess specialized knowledge, capabilities, and other valuable resources required by focal firms. Thus, there exist variations in how alliance portfolios are defined in academic studies, especially depending on the research disciplines and the objectives of alliance formation in a particular industry context. Furthermore, management scholars have argued that a portfolio-level approach toward investigating the performance impact of strategic alliances is more appropriate than a dyadic view. The prime reason is that management cannot ignore the interdependence that exists between alliance activities, the trade-offs in resource allocation and the synergies that arise from across the alliance projects. Alliance portfolios will likely offer a larger scope of opportunities for new combinations than individual bilateral alliances do. In understanding the relationship between alliance portfolios and firm performance, scholarly works have branched into these broad research inquiries: (i) the configuration of alliance portfolios, (ii) the management of alliance portfolios, and (iii) the role of alliance portfolios from a knowledge-based view. More recently, a new theme has emerged to study whether and how small and young ventures benefit from alliance portfolios. Above all, across these lines of alliance portfolios research inquiry, growing attention has been drawn to the antecedents and consequence of learning and value creation among portfolio partners, which would predict a firm’s performance in profitability, innovation, and new business development.
Community-Onset Clostridioides Difficile Infection in Hospitalized Patients in The Netherlands
Authors: Crobach M J T , Notermans D W , Harmanus C , Sanders I M J G , De Greeff S C , Kuijper E J
Published: November 2019

Background

Clostridioides difficile infection (CDI) is increasingly reported in the community. The aim of this study was to analyze characteristics of hospitalized patients with community-onset CDI (CO-CDI).

Methods

In the Netherlands, 24 hospitals (university-affiliated and general hospitals) participate in the sentinel CDI surveillance program. Clinical characteristics and 30-day outcomes of hospitalized patients >2 years old diagnosed with CDI are registered. Samples of these patients are sent to the national reference laboratory for polymerase chain reaction ribotyping. Data obtained for this surveillance from May 2012 to May 2018 were used to compare CO-CDI with hospital-onset (HO)-CDI episodes.

Results

Of 5405 registered cases, 2834 (52.4%) were reported as HO-CDI, 2174 (40.2%) were CO-CDI, and 339 (6.3%) had onset of symptoms in another healthcare facility (eg, nursing home). The proportion of CO-CDI increased over the years and was lower during winter months. Hospitalized patients with CO-CDI were younger (63.8 vs 68.0 years, P < .001) and more often females (53.0% vs 49.6%, P = .02) than patients with HO-CDI. Median time between onset of symptoms and CDI testing was longer in CO-CDI (4 vs 1 day, P < .001). Similar ribotypes were found in CO-CDI and HO-CDI, but ribotype 001 was more frequent among HO-CDI, whereas ribotype 023 was more frequent in CO-CDI. Six of 7 (85.7%) surgeries due to CDI, 27 of 50 (54%) ICU admissions due to CDI, and 48 of 107 (44.9%) of CDI-associated deaths were attributable to CO-CDI.

Conclusions

Our study demonstrates that patients hospitalized with CO-CDI contribute substantially to the total number of CDI episodes and CDI-associated complications in hospitals, stressing the need for awareness and early testing for CDI in community and outpatient settings and also in patients admitted from community with diarrhoea. Surveillance programs that also target nonhospitalized CDI patients are needed to understand the true burden and dynamics of CDI.
Restabilization of the Occipitocervical Junction After a Complete Unilateral Condylectomy: A Biomechanical Comparison of Unilateral and Bilateral Fixation Techniques
Authors: Eli Ilyas M , Karsy Michael , Brodke Darrel S , Bachus Kent N , Couldwell William T , Dailey Andrew T , Mazur Marcus D
Published: November 2019

BACKGROUND

Occipitocervical instability may result from transcondylar resection of the occipital condyle. Initially, patients may be able to maintain a neutral alignment but severe occipitoatlantal subluxation may subsequently occur, with cranial settling, spinal cord kinking, and neurological injury.

OBJECTIVE

To evaluate the ability of posterior fixation constructs to prevent progression to severe deformity after radical unilateral condylectomy.

METHODS

Eight human cadaveric specimens (Oc-C2) underwent biomechanical testing to compare stiffness under physiological loads (1.5 N m). A complete unilateral condylectomy was performed to destabilize one Oc-C1 joint, and the contralateral joint was left intact. Unilateral Oc-C1 or Oc-C2 constructs on the resected side and bilateral Oc-C1 or Oc-C2 constructs were tested.

RESULTS

The bilateral Oc-C2 construct provided the greatest stiffness, but the difference was only statistically significant in certain planes of motion. The unilateral constructs had similar stiffness in lateral bending, but the unilateral Oc-C1 construct was less stiff in axial rotation and flexion-extension than the unilateral Oc-C2 construct. The bilateral Oc-C2 construct was stiffer than the unilateral Oc-C2 construct in axial rotation and lateral bending, but there was no difference between these constructs in flexion-extension.

CONCLUSION

Patients who undergo a complete unilateral condylectomy require close surveillance for occipitocervical instability. A bilateral Oc-C2 construct provides suitable biomechanical strength, which is superior to other constructs. A unilateral construct decreases abnormal motion but lacks the stiffness of a bilateral construct. However, given that most patients undergo a partial condylectomy and only a small proportion of patients develop instability, there may be scenarios in which a unilateral construct may be appropriate, such as for temporary internal stabilization.
Military Mobility, Authority and Negotiation in Early Colonial India*
Authors: Welsch Christina
Published: November 2019

This article focuses on the career of Muhammad Yusuf Khan, an officer in the British East India Company who sought to turn his military service into political and diplomatic authority, only to be executed as a rebel in 1764. His rise and fall occurred early in the so-called colonial transition, a period characterized in recent scholarship as one of relative fluidity in contrast to later, more rigid instantiations of colonial rule. Institutionally, the Company’s armies seem to contradict that pattern: their rapid growth in the eighteenth century produced new exclusions and restrictions, including some of the earliest formal articulations of a racial binary between Indian and European actors. Yusuf Khan, however, gained political capital by mobilizing elements of those intended restrictions in new contexts, imbuing the Company’s military hierarchies with alternate meanings outside of its formal infrastructure. His innovative reinterpretation of military prestige becomes clear when the Company’s records are read alongside Persian-language material from the Indian courts against which he fashioned his political identity. His career offers insight into how the inequitable, but dynamic relationship between the Company and its soldiers shaped the former’s approach to and understanding of India s political landscape
Calanoid copepod grazing affects plankton size structure and composition in a deep, large lake
Authors: Kunzmann Alessandra Janina , Ehret Harald , Yohannes Elizabeth , Straile Dietmar , Rothhaupt Karl-Otto
Published: November 2019

Cultural oligotrophication is expected to shift lake zooplankton to become dominated by calanoid copepods. Hence, understanding the influence of calanoids on the taxonomic and size structure of the lower plankton food web is crucial for predicting the effects of oligotrophication on energy fluxes in these systems. We studied the effect of an omnivorous calanoid, Eudiaptomus gracilis, on the lower planktonic food web using an in situ incubation approach in large and deep Lake Constance. We show that E. gracilis significantly reduced ciliate, phytoplankton, rotifer, but increased bacteria biovolume. Highest clearance rates were observed for ciliates whose biovolume declines may have caused a release of predation pressure on bacteria. E. gracilis grazing shifted the size structure of the phytoplankton community by reducing mean phytoplankton cell size (directional selection) and simultaneously increasing cell size variance (disruptive selection). Ciliate cell sizes experienced a similar selective regime in one of the experiments, whereas in the other two experiments, no change of size structure was detected. Results suggest strong influences of E. gracilis grazing on the lower plankton food web and a significant shift in phytoplankton size structure. For evaluating detailed effects of omnivorous consumers on plankton size structure, cascading interactions need to be considered.
A reverse translational study on the effect of rituximab, rituximab plus belimumab, or bortezomib on the humoral autoimmune response in SLE
Authors: van Dam Laura S , Osmani Zgjim , Kamerling Sylvia W A , Kraaij Tineke , Bakker Jaap A   , Scherer Hans U , Rabelink Ton J , Voll Reinhard E , Alexander Tobias , Isenberg David A , van Kooten Cees , Teng Y K Onno
Published: November 2019

Objectives

SLE is a severe autoimmune disease characterized by autoreactive B cells and IC formation, which causes systemic inflammation. B cell–targeted therapy could be a promising treatment strategy in SLE patients; nevertheless, randomized clinical trials have not always been successful. However, some groups have demonstrated beneficial effects in severe SLE patients with off-label rituximab (RTX) with belimumab (BLM), or bortezomib (BTZ), which targeted different B cells subsets. This study assembled sera from SLE cohorts treated with RTX+BLM (n = 15), BTZ (n = 11) and RTX (n = 16) to get an in-depth insight into the immunological effects of these therapies on autoantibodies and IC formation.

Methods

Autoantibodies relevant for IC formation and the avidity of anti-dsDNA were determined by ELISA. IC-mediated inflammation was studied by complement levels and ex vivo serum-induced neutrophil extracellular trap formation.

Results

Reductions in autoantibodies were observed after all approaches, but the spectrum differed depending upon the treatment. Specifically, only RTX+BLM significantly decreased anti-C1q. Achieving seronegativity of ≥1 autoantibody, specifically anti-C1q, was associated with lower disease activity. In all SLE patients, the majority of anti-dsDNA autoantibodies had low avidity. RTX+BLM significantly reduced low-, medium- and high-avidity anti-dsDNA, while RTX and BTZ only significantly reduced medium avidity. IC-mediated inflammation, measured by C3 levels and neutrophil extracellular trap formation, improved after RTX+BLM and RTX but less after BTZ.

Conclusion

This study demonstrated the impact of different B cell–targeted strategies on autoantibodies and IC formation and their potential clinical relevance in SLE.
Philanthropy and the globally mobile
Authors: Petraske Alana
Published: November 2019

As people and wealth become more globally mobile, the traditional model of non-profit tax relief can lead to unexpected consequences. Using examples to illustrate, this article explores how philanthropy—whether direct or intermediated giving—can be frequently overlooked when considering jurisdiction and relocation, and how local residence rules can affect the tax position of philanthropic structures.
Are environmental charities getting their feet wet when they lobby for marine protection around remote islands?
Authors: Farran Sue
Published: November 2019

Recent ‘Extinction’ protests in the UK and elsewhere highlight contemporary concerns about the environment and the shared responsibility of all to take meaningful steps to save it. Key players in this advocacy are environmental charities. One of the areas in which they have been most active – in the UK and elsewhere – is in persuading governments to establish large Marine Protected Areas, especially around island territories. These are often created as ‘no-take’ areas, meaning that fishing – other than subsistence fishing – and other marine activities are prohibited, often to the detriment of local fishers. Invariably this requires a change in the current law. This article queries whether, in advocating for marine-protected areas, environmental charities are overstepping the principles which determine charitable status.
Lamb performance in hardwood silvopastures, II: animal behavior in summer1
Authors: Pent Gabriel J , Greiner Scott P , Munsell John F , Tracy Benjamin F , Fike John H
Published: November 2019

Integrating trees into pastures, a practice known as silvopasture, may benefit livestock in the summertime through the provision of shade. The purpose of this project was to compare the behavioral patterns of sheep grazing in silvopastures and open pastures. Black walnut (Juglans nigra L.) and honeylocust (Gleditisia triacanothose L.) based silvopasture systems were compared with open pastures in a randomized complete block design with three blocks over two summers. Behavior measures were recorded within a replicate within a week, and these measures were taken sequentially within three experimental periods. Ewe lambs (n = 3) within each experimental unit were equipped with a wideband audio-recording device to detect prehension events. Time-lapse cameras documented sheep behavior every 60 s. In the silvopastures, the lambs spent over 90% of daylight hours within shade from trees. Lambs in silvopastures spent more time lying down than animals in the open pastures (P ≤ 0.01), while lambs in the open pastures spent more than 2 h longer each day standing (P < 0.0001). Lambs in the black walnut silvopastures spent more time grazing (488 ± 14 min · d−1) than lambs in the honeylocust silvopastures (438 ± 14 min · d−1; P = 0.0493) and lambs in the open pastures (417 ± 14 min · d−1; P = 0.0026). There was no difference in grazing time for lambs in the latter two systems (P = 0.5597). Spectral analysis of the imagery revealed that the lambs in the black walnut silvopastures grazed more frequently than the lambs in the other systems for both years. The acoustic analysis, though limited by recorder durability to 47 complete recordings, revealed no difference in total bites taken per day (P ≥ 0.7222) or in the morning (P ≥ 0.2069), afternoon (P ≥ 0.5816), and evening periods (P ≥ 0.9337). Silvopastures provide an opportunity to improve lamb comfort in the summer.
Efficacy of Adjunctive Zinc in Improving the Treatment Outcomes in Hospitalized Children with Pneumonia: A Randomized Controlled Trial
Authors: Rerksuppaphol Lakkana , Rerksuppaphol Sanguansak
Published: November 2019

Background

The mortality rate of pneumonia is high, placing a huge burden on developing countries. Healthcare professionals use zinc as an adjunctive treatment for children with pneumonia; however, this contradicts with some published reports. Thus, this study aimed to assess the efficacy of zinc supplementation on the treatment outcomes of pneumonia.

Methods

A randomized, double-blind, placebo-controlled trial was conducted on hospitalized children with pneumonia. The children randomly received either zinc bis-glycinate (15 mg elemental zinc) or placebo, twice per day. The primary outcome was the resolution time of pneumonia, and the secondary outcomes were the duration of hospitalization and the recovery times of each clinical symptom.

Results

Out of the 91 children, 65 (71.4%) were males. The resolution period of clinical pneumonia was significantly shorter in the zinc group than the placebo group (48 and 72 h, respectively; hazard ratio = 0.585, 95% confidence interval 0.377–0.908). Similarly, the hospitalization period and the resolution period of fever were shorter in the zinc group [96 and 144 h (p = 0.008), and 24 and 42 h (p = 0.002), respectively]. Children receiving zinc needed a median of 28 h to reach the normal level of oxygen saturation compared to 48 h required by children under placebo (p = 0.014).

Conclusion

Zinc supplementation enhanced the treatment outcomes of pneumonia, by reducing the resolution period of pneumonia and normalizing oxygen levels and body temperature. The length of hospital stay for children receiving zinc was shorter than those receiving placebo.
Butyrate prevents valproate‐induced liver injury: In vitro and in vivo evidence
Authors: Pirozzi Claudio , Lama Adriano , Annunziata Chiara , Cavaliere Gina , De Caro Carmen , Citraro Rita , Russo Emilio , Tallarico Martina , Iannone Michelangelo , Ferrante Maria Carmela , Mollica Maria Pina , Mattace Raso Giuseppina , De Sarro Giovambattista , Calignano Antonio , Meli Rosaria
Published: November 2019

Sodium valproate (VPA), an antiepileptic drug, may cause dose‐ and time‐dependent hepatotoxicity. However, its iatrogenic molecular mechanism and the rescue therapy are disregarded. Recently, it has been demonstrated that sodium butyrate (NaB) reduces hepatic steatosis, improving respiratory capacity and mitochondrial dysfunction in obese mice. Here, we investigated the protective effect of NaB in counteracting VPA‐induced hepatotoxicity using in vitro and in vivo models. Human HepG2 cells and primary rat hepatocytes were exposed to high VPA concentration and treated with NaB. Mitochondrial function, lipid metabolism, and oxidative stress were evaluated, using Seahorse analyzer, spectrophotometric, and biochemical determinations. Liver protection by NaB was also evaluated in VPA‐treated epileptic WAG/Rij rats, receiving NaB for 6 months. NaB prevented VPA toxicity, limiting cell oxidative and mitochondrial damage (ROS, malondialdehyde, SOD activity, mitochondrial bioenergetics), and restoring fatty acid oxidation (peroxisome proliferator‐activated receptor α expression and carnitine palmitoyl‐transferase activity) in HepG2 cells, primary hepatocytes, and isolated mitochondria. In vivo, NaB confirmed its activity normalizing hepatic biomarkers, fatty acid metabolism, and reducing inflammation and fibrosis induced by VPA. These data support the protective potential of NaB on VPA‐induced liver injury, indicating it as valid therapeutic approach in counteracting this common side effect due to VPA chronic treatment.
Rapid actions of anti‐Müllerian hormone in regulating synaptic transmission and long‐term synaptic plasticity in the hippocampus
Authors: Wang Kang , Xu Fuhua , Campbell Shawn P. , Hart Kyle D. , Durham Tyler , Maylie James , Xu Jing
Published: November 2019

Anti‐Müllerian hormone (Amh) is a peptide factor that is known to regulate sexual differentiation and gonadal function in mammals. Although Amh is also suggested to be associated with cognitive development and function in the postnatal brain, little is known about its expression or direct effects on neuronal activities in the hippocampus. Therefore, we assessed Amh and its receptor expression in the hippocampus of male and female mice using PCR, Western blot, and immunofluorescence staining. While Amh‐specific receptor expression was comparable between males and females, mRNA and protein levels of Amh were higher in females than those of males. Electrophysiological recordings on acute hippocampal slices showed that exogenous Amh protein addition increased synaptic transmission and long‐term synaptic plasticity at the Cornu Ammonis (CA) 3‐CA1 synapses. Amh exposure also increased the excitatory postsynaptic potential at CA1 synapses. Our findings support direct and rapid actions of Amh as a paracrine and/or autocrine factor in regulating hippocampal neuronal activities. Data provide functional evidence of Amh‐mediated postsynaptic modulation of synaptic transmission and Amh‐regulated long‐term synaptic plasticity in the hippocampus. These results suggest a potential role of Amh in learning and memory, and a possible cause of the sex differences in cognitive development and function.
Methemoglobinemia in a 14-year-old girl with new-onset dyspnea
Authors: Wallace Michelle , Tenbarge Caitlin , Harlow Sofia , Kasting Nathan , Gooden Justin
Published: November 2019

Methemoglobinemia is a rare and potentially life-threatening medical emergency that can be overlooked when evaluating a patient in respiratory distress. Without early recognition, patients may develop respiratory failure and die. This article describes a teenager who presented to the ED for dyspnea and lightheadedness and failed to respond to supplemental oxygen. She was eventually diagnosed with methemoglobinemia.
Preventing kidney injury by avoiding fluid overload in patients with sepsis
Authors: Dodd Rebecca L. , Archambault Mark E.
Published: November 2019

The global epidemiologic burden of sepsis is difficult to ascertain. Sepsis affects more than 31.5 million people worldwide every year, potentially resulting in 5 million deaths. Up to one-third of patients with sepsis also develop sepsis-associated acute kidney injury. This article describes the need for restraint in fluid resuscitation in patients with sepsis, in order to mitigate end-organ damage and ultimately to save lives.
Haematogenous Spondylodiscitis in Patients With Liver Cirrhosis
Authors: Abdelrahman Hemdan , Shousha Mootaz , Bahrami Reza , Boehm Heinrich
Published: November 2019

Study Design.

A retrospective study of 36 liver cirrhosis patients presenting with spondylodiscitis.

Objectives.

The aim of this study was to analyze the characteristics of spondylodiscitis in the presence of liver cirrhosis and furthermore, to evaluate the outcome of surgery in this specific group of patients.

Summary of Background Data.

The incidence of haematogenous spondylodiscitis is increasing. The coexistence of liver cirrhosis makes the course of the disease more aggressive.

Methods.

A total of 36 liver cirrhosis patients presented with haematogenous spondylodiscitis. The onset of infection, clinical course and outcomes of management were reviewed retrospectively.

Results.

The associated comorbidities were cardiac in 17 patients, diabetes in 19, renal insufficiency in 16, and another focus for infection in nine cases. Neurological deficits were found in 24 patients (67%) and fever in 15 cases. Nine patients had septic manifestations. The lumbar spine was affected in 25 patients (69%). Noncontiguous spinal infection was found in nine patients (25%) and epidural abscess in 24 individuals. The preoperative C-reactive protein was elevated in all cases. The causative organism was most commonly Staphylococcus aureus (17 patients). A combined anteroposterior approach was necessary in 28 patients and a minimallly invasive surgery was performed in 30 cases. In-hospital mortality was 14% (5 patients). The neurological improvement rate was 82%. The postoperative antibiotic therapy was taken for more than 8 weeks in 22 patients. In 15 patients, a combination of antibiotics was necessary.

Conclusion.

Spinal infection in the presence of liver cirrhosis is challenging. The rate epidural abscess formation is relatively high. Early diagnosis remains the main cornerstone in the management and the indication for surgery should be carefully considered. Minimally invasive techniques should be used when possible to minimize complication rate, and higher amounts of intraoperative blood loss should be expected.

Level of Evidence: 4
The Effect of Paraspinal Muscle Degeneration on Distal Pedicle Screw Loosening Following Corrective Surgery for Degenerative Lumbar Scoliosis
Authors: Leng Junsheng , Han Gengyu , Zeng Yan , Chen Zhongqiang , Li Weishi
Published: November 2019

Mini

A total of 137 degenerative lumbar scoliosis patients were divided into two groups. In group A (six or more fused levels), mean rFCSA of erector spinae <0.71 was an independent risk factor of LIV screw loosening. In Group B (four or five fused levels), paraspinal muscle degeneration had no influence on LIV screw loosening.

Study Design.

A retrospective study.

Objective.

The aim of this study was to evaluate the effect of degeneration of paraspinal muscles, including psoas muscles, erector spinae muscles, and multifidus muscles on pedicle screw loosening at lower instrumented vertebra (LIV) following corrective surgery for degenerative lumbar scoliosis (DLS).

Summary of Background Data.

The relation between paraspinal muscles and pedicle screw loosening in DLS patients has not been reported.

Methods.

A total of 137 DLS patients underwent corrective surgery with at least 1-year follow-up were included. The patients were divided into two groups: Group A (68 patients) had six or more fused levels and Group B (69 patients) had four or five fused levels. Muscular parameters, including relative cross-sectional area (rCSA) and muscle-fat index (MFI), were measured on preoperative magnetic resonance imaging. rCSA and MFI were measured for both gross muscle (G) and functional muscle (F) as rGCSA, rFCSA, GMFI, and FMFI. Muscle ratio was calculated as rFCSA/rGCSA. Pedicle screw loosening was assessed on spine radiographs or CT at final follow-up. Clinical and radiological screw loosening were classified according to clinical significance.

Results.

LIV screw loosening occurred in 77 patients at final follow-up. In Group A, patients with LIV screw loosening had significantly higher FMFI of psoas muscles and lower rFCSA and rGCSA of erector spinae. Logistic regression revealed that mean rFCSA of erector spinae <0.71 (odds ratio = 5.0, 95% confidence interval = 1.5–16.4) was an independent risk factor of LIV screw loosening. Mean muscle ratio of erector spinae was significantly lower in patients with clinical screw loosening compared with radiological screw loosening in univariate analysis. In Group B, all muscular parameters showed no significant difference.

Conclusion.

Degeneration of paraspinal muscles, especially psoas muscles and erector spinae, affected LIV screw loosening in six or more level fusion in corrective surgery for DLS, whereas the four- or five-level fusion had no this influence.

Level of Evidence: 3
Improvement in Patient Mental Well-being After Surgery for Cervical Spondylotic Myelopathy
Authors: Tamai Koji , Suzuki Akinobu , Terai Hidetomi , Hoshino Masatoshi , Toyoda Hiromitsu , Takahashi Shinji , Ohyama Shoichiro , Hori Yusuke , Yabu Akito , Nakamura Hiroaki
Published: November 2019

Study Design.

Retrospective cohort study.

Objective.

The aim of this study was to investigate changes in mental well-being after surgery for cervical spondylotic myelopathy (CSM) and identify factors associated with improvement.

Summary of Background Data.

Posterior cervical surgery with laminoplasty significantly improves myelopathy and physical function in patients with CSM. However, its impact on mental well-being is unclear.

Methods.

Patients who underwent laminoplasty for CSM and had >2 years of follow-up were reviewed (n = 111). The mental component summary (MCS) score was used as a measure of mental well-being. The trend in MCS score change was evaluated using the Jonckheere-Terpstra trend test. Preoperative clinical scores were compared between patients with improvements greater and less than the minimal clinically important difference (MCID). Significant variables were included in a multinomial logistic regression analysis and further validated in a receiver-operating characteristic (ROC) curve analysis. Additionally, the results were confirmed in a long-term observation cohort of patients followed up for >5 years (n = 46).

Results.

The improvement in the average MCS score (5.6) was greater than the MCID (4.0). The trend of improvement was sustained for 2 years (P = 0.002), but not for 5 years (P = 0.130). In terms of individual cases, 56 patients (50.5%) achieved MCS score improvement greater than the MCID. These patients showed significantly lower preoperative MCS scores than those without meaningful improvement (P < 0.001). The preoperative “social functioning (SF)” score was independently associated with MCS score improvement (P = 0.001). ROC curve analysis validated the ability of preoperative SF to predict MCS score improvement at 2 and 5 years postoperatively (area under the curve: 0.744, 0.893, respectively).

Conclusion.

Half of the patients achieved meaningful improvement in mental well-being. A lower preoperative SF score was independently associated with improvement. These results may help identify patients who could experience an improvement in mental well-being after surgery and develop novel approaches to achieve further improvement.

Level of Evidence: 3
The Screw–Aorta Dilemma
Authors: Sarwahi Vishal , Galina Jesse , Wendolowski Stephen , Thornhill Beverly , Atlas Aaron , Gecelter Rachel , Hasan Sayyida , Lo Yungtai , Amaral Terry D.
Published: November 2019

Study Design.

Retrospective chart review.

Objective.

To determine if obtaining a prone computed tomography (CT)-scan can better delineate a questionable screw–aorta relationship.

Summary of Background Data.

Pedicle screw misplacement rate is reported between 6% and 15%. Studies looking at misplacements on a per patient basis show up to 14% of patients have screws at risk (impinging vital structures). A screw abutting the aorta is a management challenge and often requires vascular surgery intervention. However, CT scans routinely done in supine position may overestimate screw–aorta relationship. Change in patient position may allow the aorta to roll away and, in most cases, reveal an uncompromised aorta. This will allow safe removal of pedicle screws without any vascular intervention.

Methods.

One hundred eleven spinal deformity patients who underwent Posterior spinal fusion from 2004 to 2009 were evaluated. Patients with concerning screw–aorta relationship underwent additional prone CT scan. Mobility of the aorta was determined and distance was compared using prone and supine CT scans.

Results.

Two thousand two hundred ninety five screws were reviewed, 36 screws in 18 patients were in proximity to the aorta. Fourteen screws (nine patients) appeared to be impinging the aorta. On prone CT, 13 out of the 14 instances the aorta moved away from the screw. The average distance at the screw level was 13.6 ± 4.8 mm in supine position and 8.9 ± 5.4 mm in prone position (P = 0.001). In one instance the relationship was unchanged on prone CT. No screw was noted to violate the lumen or distort the aorta.

Conclusion.

Supine CT scan alone is not entirely accurate in determining screw–aorta relationship. Prone-CT scan provides additional information for better delineation. This additional diagnostic step can change the treatment option by limiting the need for vascular intervention. When in doubt, the additional use of an arteriogram can allow for improved visualization.

Level of Evidence: 3
Postoperative Kyphosis in Cervical Spondylotic Myelopathy
Authors: Machino Masaaki , Ando Kei , Kobayashi Kazuyoshi , Morozumi Masayoshi , Tanaka Satoshi , Kanbara Shunsuke , Ito Sadayuki , Inoue Taro , Ito Keigo , Kato Fumihiko , Ishiguro Naoki , Imagama Shiro
Published: November 2019

Study Design.

A prospective cohort study.

Objective.

This study aimed to investigate the relationship between preoperative cervical sagittal alignment and postoperative kyphosis in patients with cervical spondylotic myelopathy (CSM) and to determine the cut-off angle for predicting the postlaminoplasty kyphosis.

Summary of Background Data.

There have been several reports describing a cervical kyphosis after laminoplasty. However, there has been no study on the cut-off angle for predicting the postoperative kyphosis in a large series of patients with CSM.

Methods.

A total of 1025 consecutive patients with CSM (642 men and 383 women; mean age, 64.4 yr; range, 23–93 yrs) who underwent laminoplasty were included. The average follow-up period was 30.0 months. Radiography was performed before the surgery and at final follow-up. The cervical alignment with neutral view was measured by using the Cobb method. An alignment of C2–7 lordotic angle more than 0° was defined as lordosis and C2–7 lordotic angle less than 0° was defined as kyphosis. The incidence of postoperative kyphosis was evaluated on lateral radiographs.

Results.

In all patients, the mean C2–7 alignment in the neutral position was 11.5° lordotic before surgery and 14.2° lordotic at final follow-up. In the patient without preoperative kyphotic alignment, receiver operating characteristic curve of preoperative C2–7 lordotic angle showed 7° as a predictor for the postlaminoplasty kyphosis (area under the curve  = 0.75, P < 0.0001). Among the preoperatively 720 patients with lordosis more than 7°, postoperative kyphosis was observed in 20 patients (2.8%), whereas in the preoperatively 191 patients with lordosis less than 7°, postoperative kyphosis was seen in 28 patients (14.7%).

Conclusion.

The cut-off value of preoperative C2–7 lordotic angle for predicting the postlaminoplasty kyphosis was 7° in CSM patient without preoperative kyphotic alignment.

Level of Evidence: 3
The Oblique Corridor at L4-L5
Authors: Ng Julia Poh-Hwee , Kaliya-Perumal Arun-Kumar , Tandon Ankit Anil , Oh Jacob Yoong-Leong
Published: November 2019

Study Design.

Cross-sectional radioanatomical study.

Objective.

The aim of this study was to analyze the prevalence, size, and location of the oblique corridor (OC), and the morphology of the psoas muscle at the L4-L5 disc level.

Summary of Background Data.

Lateral lumbar interbody fusion via the OC has the advantage of avoiding injury to the psoas muscle and lumbar plexus. However, the varying anatomy of major vascular structures and the iliopsoas may preclude a safe oblique access to the L4-L5 level.

Methods.

Five hundred axial magnetic resonance images of the L4-L5 disc level were shortlisted. OCs were categorized into four grades: Grade 0 = no corridor, Grade 1 = small corridor (≤1 cm), Grade 2 = moderate corridor (1–2 cm) and Grade 3 = large corridor (>2 cm). OC location was labeled as antero-oblique, oblique, or oblique-lateral. Psoas morphology was categorized based on a modified Moro's classification, where the anterior section was further subdivided into types AI-AIV. Oblique approach was considered nonviable either when there was no corridor due to vascular obstruction (Grade 0) or when the psoas was high-rising (Types AII-AIV).

Results.

10.5% of the selected 449 patients had no measurable OC (grade 0) at the L4-L5 level. There were 35% and 37.2% patients with a grade 1and 2 OC, respectively. The location of the OC was anterior oblique, oblique, and oblique lateral in 3.7%, 89.6%, and 6.7%, respectively. According to the modified Moro's classification, 19.4% had a high-rising psoas. Predominantly, psoas was either in line with the disc (Type I; 30.7%) or low-rising (Type AI; 47.4%).

Conclusion.

Twenty-five percent of the patients did not have an accessible OC either due to obstruction by vascular structures or due to a high-rising psoas. Hence, proper evaluation of the relevant anatomy preoperatively is recommended for early adopters of this technique, as varying anatomy precludes universal suitability of oblique lateral interbody fusion for the L4-L5 level.

Level of Evidence: 3
Extradural Contralateral C7 Nerve Root Transfer in a Cervical Posterior Approach for Treating Spastic Limb Paralysis
Authors: Yang Kaixiang , Jiang Fan , Zhang Shaohua , Zhao Haiqiang , Shi Zongpo , Liu Jun , Cao Xiaojian
Published: November 2019

Study Design.

Anatomic study in nine fresh-frozen cadavers.

Objective.

To confirm the anatomical feasibility of transferring the extradural ventral roots (VRs) and dorsal roots (DRs) of contralateral C7 nerves to those of the ipsilateral C7 nerves respectively through a cervical posterior approach.

Summary of Background Data.

The contralateral C7 nerve root transfer technique makes breakthrough for treating spastic limb paralysis. However, its limitations include large surgical trauma and limited indications.

Methods.

Nine fresh-frozen cadavers (four females and five males) were placed prone, and the feasibility of exposing the bilateral extradural C7 nerve roots, separation of the extradural C7 VR and DR, and transfer of the VR and DR of the contralateral C7 to those of the ipsilateral C7 on the dural mater were assessed. The pertinent distances and the myelography results of each specimen were analyzed. The acetylcholinesterase (AChE) and antineurofilament 200 (NF200) double immunofluorescent staining were preformed to determine the nerve fiber properties.

Results.

A cervical posterior midline approach was made and the laminectomy was performed to expose the bilateral extradural C7 nerve roots. After the extradural C7 VR and DR are separated, the VR and DR of the contralateral C7 have sufficient lengths to be transferred to those of the ipsilateral C7 on the dural mater. The myelography results showed that the spinal cord is not compressed after the nerve anastomosis. The AChE and NF200 double immunofluorescent staining showed the distal ends of the contralateral C7 VRs were mostly motor nerve fibers, and the distal ends of the contralateral C7 DRs were mostly sensory nerve fibers.

Conclusion.

Extradural contralateral C7 nerve root transfer in a cervical posterior approach for treating spastic limb paralysis is anatomically feasible.

Level of Evidence: 5.