MR imaging evaluation of accidental third molar displacement into parapharyngeal space: a case report.

Accidental displacement of impacted and non-erupted upper third molars into the maxillary sinus, buccal space, infratemporal fossa, and lateral pharyngeal space is uncommon. Herein, we present an unusual case of parapharyngeal cellulitis secondary to iatrogenic displacement of the right third molar. Clinical history, physical examination, and imaging assessment are essential in the evaluation of teeth projected into adjacent anatomic spaces.

Cancer cells suppress NK cell activity by actin-driven polarization of inhibitory ligands to the immunological synapse.

Natural killer (NK) cells engage target cells via the immunological synapse (IS), where inhibitory and activating signals determine whether NK cell cytotoxicity is suppressed or activated. We previously reported that cancer cells can rapidly remodel their actin cytoskeleton upon NK cell engagement, leading to F-actin accumulation at the synapse. Here, we show that this process inhibits NK cell activation as indicated by impaired MTOC and lytic granule polarization.

Real-Life Performance of a Commercially Available AI Tool for Post-Traumatic Intracranial Hemorrhage Detection on CT Scans: A Supportive Tool.

: Traumatic brain injury (TBI) is a major cause of morbimortality in the world, and it can cause potential intracranial hemorrhage (ICH), a life-threatening condition that requires rapid diagnosis with computed tomography (CT). Artificial intelligence tools for ICH detection are now commercially available. : Investigate the real-world performance of qER.

A comprehensive guide to study the immunological synapse using imaging flow cytometry.

Cytotoxic lymphocytes, such as cytotoxic T cells and natural killer (NK) cells, are instrumental in the recognition and eradication of pathogenic cells, notably those undergoing malignant transformation. Cytotoxic lymphocytes establish direct contact with cancer cells via the formation of a specialized cell-cell junction known as the lytic immunological synapse. This structure serves as a critical platform for lymphocytes to integrate surface signals from potential cancer cells and to direct their cytolytic apparatus toward the confirmed targets.

F-Naf PET/CT in pseudarthrosis after anterior cervical discectomy and fusion.

Background Context: Pseudarthrosis is a well-known cause of persistent or recurrent pain after anterior cervical discectomy and fusion (ACDF). Numerous radiographic criteria to determine the fusion status has been described in the literature, but their accuracies in clinical practice vary considerably and no 1 single method has proved superior. Fluorine-18 sodium fluoride (F-NaF) positron emission tomography/computed tomography (PET/CT), depicting osteoblastic activity, might be useful to identify pseudarthrosis after ACDF.

Value of F-FDG PET/CT to Identify Occult Infection in Presumed Aseptic Pseudarthrosis after Spinal Fusion: Correlation with Intraoperative Cultures.

 Fluorine-18 fluorodeoxyglucose ( F-FDG) positron emission tomography/computed tomography (PET/CT) has gained attention as an emerging tool in case of suspicion of infection on spine, whether native or instrumented. However, the diagnostic performance of F-FDG PET/CT in clinically occult low-grade surgical site infection (SSI) after spinal fusion, an important risk factor for pseudarthrosis, remains unknown.  We retrospectively identified all the presumed aseptic patients with pseudarthrosis confirmed by revision surgery who underwent preoperative F-FDG PET/CT scans performed between April 2019 and November 2022.

Assessment of the tolerance angle for pedicle screw insertion.

Cannulation process intervenes before implantation of pedicle screw and depends on the surgeon's experience. A reliable experimental protocol has been developed for the characterization of the slipping behavior of the surgical tool on the cortical shell simulated by synthetic materials. Three types of synthetic foam samples with three different densities were tested using an MTS Acumen 3 A/T electrodynamic device with a tri-axis 3 kN Kistler load cell mounted on a surgical tool, moving at a constant rotational speed of 10° mm and performing a three-step cannulation test.

Diagnostic and Therapeutic Issues in Glioma Using Imaging Data: The Challenge of Numerical Twinning.

Glial tumors represent the leading etiology of primary brain tumors. Their particularities lie in (i) their location in a highly functional organ that is difficult to access surgically, including for biopsy, and (ii) their rapid, anisotropic mode of extension, notably via the fiber bundles of the white matter, which further limits the possibilities of resection. The use of mathematical tools enables the development of numerical models representative of the oncotype, genotype, evolution, and therapeutic response of lesions.

Actin cytoskeleton remodeling at the cancer cell side of the immunological synapse: good, bad, or both?

Cytotoxic lymphocytes (CLs), specifically cytotoxic T lymphocytes and natural killer cells, are indispensable guardians of the immune system and orchestrate the recognition and elimination of cancer cells. Upon encountering a cancer cell, CLs establish a specialized cellular junction, known as the immunological synapse that stands as a pivotal determinant for effective cell killing. Extensive research has focused on the presynaptic side of the immunological synapse and elucidated the multiple functions of the CL actin cytoskeleton in synapse formation, organization, regulatory signaling, and lytic activity.

Sliding on cortical shell: Biomechanical characterization of the vertebral cannulation for pedicle screw insertion.

Background: Pedicular screws pull-out has been well studied unlike their insertion. A need for characterizing cannulation before pedicle screw implantation is highlighted in literature and offers promising prospects for future intra-operation instrumentation. A reliable cannulation protocol for ex-vivo testing in swine and cadaver vertebrae is presented in this work to predict extra pedicular perforation.

Correlative light and electron microscopy to explore the lytic immunological synapse between natural killer cells and cancer cells.

Cytotoxic lymphocytes, such as natural killer (NK) cells and cytotoxic T cells, can recognize and kill tumor cells by establishing a highly specialized cell-cell contact called the immunological synapse. The formation and lytic activity of the immunological synapse are accompanied by local changes in the organization, dynamics and molecular composition of the cell membrane, as well as the polarization of various cellular components, such as the cytoskeleton, vesicles and organelles. Characterization and understanding of the molecular and cellular processes underlying immunological synapse formation and activity requires the combination of complementary types of information provided by different imaging modalities, the correlation of which can be difficult.

A randomized, controlled, prehabilitation intervention to maximize early recovery (PRIMER) in liver transplantation.

Frailty and impaired functional status are associated with adverse outcomes on the liver transplant (LT) waitlist and after transplantation. Prehabilitation prior to LT has rarely been tested. We conducted a 2-arm patient-randomized pilot trial to evaluate the feasibility and efficacy of a 14-week behavioral intervention to promote physical activity prior to LT.

Actin cytoskeleton depolymerization increases matrix metalloproteinase gene expression in breast cancer cells by promoting translocation of cysteine-rich protein 2 to the nucleus.

The actin cytoskeleton plays a critical role in cancer cell invasion and metastasis; however, the coordination of its multiple functions remains unclear. Actin dynamics in the cytoplasm control the formation of invadopodia, which are membrane protrusions that facilitate cancer cell invasion by focusing the secretion of extracellular matrix-degrading enzymes, including matrix metalloproteinases (MMPs). In this study, we investigated the nuclear role of cysteine-rich protein 2 (CRP2), a two LIM domain-containing F-actin-binding protein that we previously identified as a cytoskeletal component of invadopodia, in breast cancer cells.

An integrated workflow for phosphopeptide identification in natural killer cells (NK-92MI) and their targets (MDA-MB-231) during immunological synapse formation.

Here, we present a protocol to identify and quantify phosphopeptides during the dynamic formation of an immunological synapse. We describe steps for mixing isotope-labeled immune and target cells, the stabilization of cell-to-cell conjugates by cross-linking, and their isolation by fluorescence-activated cell sorting. We detail the isolation of phosphopeptides by phosphopeptide enrichment and their subsequent measurement by mass spectrometry.

F-NaF PET/CT in Presumed Aseptic Pseudarthrosis after Spinal Fusion: Correlation with Findings at Revision Surgery and Intraoperative Cultures.

 Conventional imaging is useful to assess interbody fusion by showing complete trabecular bony bridging, but has a low positive predictive value for pseudarthrosis. Because alterations of bone metabolism may precede structural anatomical changes on computed tomography (CT), we aimed to investigate the ability of fluorine 18 sodium fluoride positron emission tomography/computed tomography ( F-NaF PET/CT) to identify pseudarthrosis after spinal fusion using surgical revision as the reference standard.  We retrospectively reviewed F-NaF PET/CT scans performed between February 2019 and September 2020 in patients experiencing pain after spinal fusion.

How natural killer cells avoid self-destruction when killing their targets.

How cytotoxic lymphocytes are protected against their own weapons during close combat with diseased target cells is an important and long-standing question in immunology. A study in this issue provides new insights into the mechanisms by which natural killer (NK) cells avoid self-destruction.

Intrinsic Resistance of Chronic Lymphocytic Leukemia Cells to NK Cell-Mediated Lysis Can Be Overcome by Pharmacological Inhibition of Cdc42-Induced Actin Cytoskeleton Remodeling.

Natural killer (NK) cells are innate effector lymphocytes with strong antitumor effects against hematologic malignancies such as chronic lymphocytic leukemia (CLL). However, NK cells fail to control CLL progression on the long term. For effective lysis of their targets, NK cells use a specific cell-cell interface, known as the immunological synapse (IS), whose assembly and effector function critically rely on dynamic cytoskeletal changes in NK cells.

The multiple roles of actin-binding proteins at invadopodia.

Invadopodia are actin-rich membrane protrusions that facilitate cancer cell dissemination by focusing on proteolytic activity and clearing paths for migration through physical barriers, such as basement membranes, dense extracellular matrices, and endothelial cell junctions. Invadopodium formation and activity require spatially and temporally regulated changes in actin filament organization and dynamics. About three decades of research have led to a remarkable understanding of how these changes are orchestrated by sequential recruitment and coordinated activity of different sets of actin-binding proteins.

Efficacy of chest CT scan for COVID-19 diagnosis in a low prevalence and incidence region.

Objectives: Value of chest CT was mainly studied in area of high COVID-19 incidence. The aim of this study was therefore to evaluate chest CT performances to diagnose COVID-19 pneumonia with regard to RT-PCR as reference standard in a low incidence area.

Methods: A survey was sent to radiology department in 4 hospitals in an administrative French region of weak disease prevalence (3.

Higher Incidence of B Cell Malignancies in Primary Immunodeficiencies: A Combination of Intrinsic Genomic Instability and Exocytosis Defects at the Immunological Synapse.

Congenital defects of the immune system called primary immunodeficiency disorders (PID) describe a group of diseases characterized by a decrease, an absence, or a malfunction of at least one part of the immune system. As a result, PID patients are more prone to develop life-threatening complications, including cancer. PID currently include over 400 different disorders, however, the variety of PID-related cancers is narrow.

Escape of tumor cells from the NK cell cytotoxic activity.

In recent years, NK cells, initially identified as potent cytotoxic effector cells, have revealed an unexpected complexity, both at phenotypic and functional levels. The discovery of different NK cell subsets, characterized by distinct gene expression and phenotypes, was combined with the characterization of the diverse functions NK cells can exert, not only as circulating cells, but also as cells localized or recruited in lymphoid organs and in multiple tissues. Besides the elimination of tumor and virus-infected cells, these functions include the production of cytokines and chemokines, the regulation of innate and adaptive immune cells, the influence on tissue homeostasis.

Efficacy of Chest CT for COVID-19 Pneumonia Diagnosis in France.

Background The role and performance of chest CT in the diagnosis of the coronavirus disease 2019 (COVID-19) pandemic remains under active investigation. Purpose To evaluate the French national experience using chest CT for COVID-19, results of chest CT and reverse transcription polymerase chain reaction (RT-PCR) assays were compared together and with the final discharge diagnosis used as the reference standard. Materials and Methods A structured CT scan survey (NCT04339686) was sent to 26 hospital radiology departments in France between March 2, 2020, and April 24, 2020.