Cervical Spine Inhomogeneously Enhancing Lesion: Avoiding Confirmation Bias

Confirmation bias is the tendency to seek information and evidence in order to confirm a preexisting hypothesis while giving less importance and overlook an alternative solution. This report describes the case of a 52-year-old man with a long history of neck pain and bilateral upper limbs paresthesias with a cervical intracanal inhomogeneously enhancing lesion. Despite all the preoperative radiological findings, a spinal meningioma an anterior approach was performed. The mass ended up being a large migrated hernia with the involvement of two levels. Before suggesting treatment, especially surgery, physicians and practitioners need to evaluate all of the possible alternatives in order to optimize patient outcome

3D-printed guides for cervical pedicle screw placement in primary spine tumor: Case report and technical description

INTRODUCTION: For spine surgeons, dealing with unstable cervical spine has been usually challenging, and this becomes more difficult when facing a primary craniovertebral junction tumor. Primary spine tumor surgery should always include column reconstruction in order to guarantee biomechanical stability of the spine, but surgeons should always be aware that instrumentations could create interferences with postoperative radiations. However, although carbon fiber instrumentations have started to be used in thoracolumbar oncology for few years, these options are still not available for cervical spine. In the reported case, the adopted strategy to obtain adequate column reconstruction was based on the idea of reducing the amount of titanium needed for posterior fixation and maximizing the distance between the radiation target and titanium rods. CASE REPORT AND AIM: We present the case of a 53-year-old woman harboring a craniovertebral junction chordoma. A short occipito-C3 construct was selected. Specifically, titanium cervical pedicle screws were placed by using a new technology consisting in patient-tailored and customized 3D-printed guides. The aim of this case report is to determine the feasibility and safety of 3D-printed guides for cervical pedicle screw (CPS) positioning, even in the case of cervical spine tumor. CONCLUSION: CPS could represent a good solution by providing strong biomechanical purchase and tailored 3D-printed guides could increase the safety and the accuracy of this challenging screw placement, even in oncological patients

The economics of debt clearing mechanisms

We examine the evolution of decentralized clearinghouse mechanisms from the 13th to the 18th century; in particular, we explore the clearing of non- or limitedtradable debts like bills of exchange. We construct a theoretical model of these clearinghouse mechanisms, similar to the models in the theoretical matching literature, and show that specific decentralized multilateral clearing algorithms known as rescontre, skontrieren or virement des parties used by merchants were efficient in specific historical contexts. We can explain both the evolutionary self-organizing emergence of late medieval and early modern fairs, and its robustness during the 17th and 18th century

Insights into the high-energy γ-ray emission of Markarian 501 from extensive multifrequency observations in the Fermi era

We report on the γ-ray activity of the blazar Mrk 501 during the first 480 days of Fermi operation. We find that the average Large Area Telescope (LAT) γ-ray spectrum of Mrk 501 can be well described by a single power-law function with a photon index of 1.78 ± 0.03. While we observe relatively mild flux variations with the Fermi-LAT (within less than a factor of two), we detect remarkable spectral variability where the hardest observed spectral index within the LAT energy range is 1.52 ± 0.14, and the softest one is 2.51 ± 0.20. These unexpected spectral changes do not correlate with the measured flux variations above 0.3 GeV. In this paper, we also present the first results from the 4.5 month long multifrequency campaign (2009 March 15-August 1) on Mrk 501, which included the Very Long Baseline Array (VLBA), Swift, RXTE, MAGIC, and VERITAS, the F-GAMMA, GASP-WEBT, and other collaborations and instruments which provided excellent temporal and energy coverage of the source throughout the entire campaign. The extensive radio to TeV data set from this campaign provides us with the most detailed spectral energy distribution yet collected for this source during its relatively low activity. The average spectral energy distribution of Mrk 501 is well described by the standard one-zone synchrotron self-Compton (SSC) model. In the framework of this model, we find that the dominant emission region is characterized by a size ≲0.1 pc (comparable within a factor of few to the size of the partially resolved VLBA core at 15-43 GHz), and that the total jet power (≃1044 erg s-1) constitutes only a small fraction (∼10-3) of the Eddington luminosity. The energy distribution of the freshly accelerated radiating electrons required to fit the time-averaged data has a broken power-law form in the energy range 0.3 GeV-10 TeV, with spectral indices 2.2 and 2.7 below and above the break energy of 20 GeV. We argue that such a form is consistent with a scenario in which the bulk of the energy dissipation within the dominant emission zone of Mrk 501 is due to relativistic, proton-mediated shocks. We find that the ultrarelativistic electrons and mildly relativistic protons within the blazar zone, if comparable in number, are in approximate energy equipartition, with their energy dominating the jet magnetic field energy by about two orders of magnitude. © 2011. The American Astronomical Society

Both lactoferrin and iron influence aggregation and biofilm formation in Streptococcus mutans

Streptococcus mutans, a gram-positive immobile bacterium, is an oral pathogen considered to be the principal etiologic agent of dental caries. Although some researches suggest that trace metals, including iron, can be associated with dental caries, the function of salivary iron and lactoferrin in the human oral cavity remains unclear. The data reported in this study indicates that iron-deprived saliva (Fe3+ 1 microM) inhibits both phenomena. Our findings are consistent with the hypothesis that S. mutans aggregation and biofilm formation are negatively iron-modulated as confirmed by the different effect of bovine lactoferrin (bLf), added to saliva at physiological concentration (20 microg/ml) in the apo- or iron-saturated form. Even if saliva itself induces bacterial aggregation, iron binding capability of apo-bLf is responsible for the noticeable increase of bacterial aggregation and biofilm development in the fluid and adherent phases. On the contrary, iron-saturated bLf decreases aggregation and biofilm development by supplying iron to S. mutans. Therefore, the iron-withholding capability of apo-Lf or native Lf is an important signal to which S. mutans counteracts by leaving the planktonic state and entering into a new lifestyle, biofilm, to colonize and persist in the human oral cavity. In addition, another function of bLf, unrelated to its iron binding capability, is responsible for the inhibition of the adhesion of S. mutans free, aggregated or biofilm on abiotic surfaces. Both these activities of lactoferrin, related and unrelated to the iron binding capability, could have a key role in protecting the human oral cavity from S. mutans pathogenicity

A Multicenter Network Analysis Examining the Psychological Effects of the COVID-19 Pandemic on Patients with Eating Disorders versus Their Healthy Siblings

(1) Background: The impact of the COVID-19 pandemic on individuals with eating disorders (EDs) has been recorded all over the world; the traumatic effects of COVID-19 have exacerbated specific and general psychopathologies in those with EDs. Comparing patients’ and their healthy siblings’ responses might help one evaluate whether there are significant differences between healthy individuals and those struggling with EDs in regard to posttraumatic psychological symptoms. (2) Methods: A sample of 141 ED patients and 99 healthy siblings were enrolled in this study in two different centers specializing in ED treatment. All participants completed the posttraumatic stress disorder (PTSD) checklist and an eating and general psychopathological self-report questionnaire. Network analysis was then applied to evaluate the differences between the populations. (3) Results: No significant differences emerged between the network structures despite the significant differences between patients and their healthy siblings in regard to posttraumatic symptoms, eating, and general psychopathology. (4) Conclusion: The complex nature of the interaction between environmental and personal factors should be evaluated further in individuals with EDs due to how they respond to traumatic events, which exacerbate patients’ psychopathology