25 research outputs found

    A rare case of intracranial malignant triton tumor arising in the middle cranial fossa: A case report and review of the literature

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    We describe a rare case of intracranial malignant triton tumor (MTT) arising in the middle cranial fossa in a 74-year-old female patient who had previously been exposed to radiation in the Chernobyl disaster. The patient underwent a surgical subtotal removal of the mass and radiation therapy, but the progression-free survival was only 2.5 months and death occurred four months after the onset of symptoms. MTTs are rare aggressive tumors arising from the nerve sheath showing rhabdomyosarcomatous differentiation and associated with a poor prognosis. The intracranial location is very rare, and only 10 cases, including the present report, have been described so far. Among intracranial MTTs, the cerebellopontine angle is the most common location. Neurofibromatosis type 1 (NF-1) and radiation exposure are risk factors as for MTTs located in other sites. The gold standard therapy is surgical excision followed by radiation therapy, but the prognosis is usually very poor

    Modulation of rat brain calpastatin efficiency by post-translational modifications

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    AbstractCalpains, the thiol proteinases of the calcium-dependent proteolytic system, are regulated by a natural inhibitor, calpastatin, which is present in brain tissue in two forms. Although both calpastatins are highly active on human erythrocyte calpain, only one form shows a high inhibitory efficiency with both rat brain calpain isozymes. The second calpastatin form is almost completely inactive against homologous proteinases and can be converted into an active one by exposure to a phosphoprotein phosphatase, also isolated from rat brain. Phosphorylation of the active calpastatin by protein kinase C and protein kinase A promotes a decrease in its inhibitory efficiency. The interconversion between the two inhibitor forms seems involved in the adjustment of the level of intracellular calpastatin activity on specific cell requirements

    Autolysis of human erythrocyte calpain produces two active enzyme forms with different cell localization

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    AbstractThe 80 kDa human erythrocyte calpain, when exposed to Ca2+, undergoes autoproteolysis that generates a 75 kDa species, with an increase in Ca2+ affinity. It is demonstrated here that this proteolytic modification proceeds through an initial step producing a 78 kDa form which is rapidly converted to the 75 kDa one. In the presence of the calpain inhibitor E-64, the 78 kDa form accumulates and only small amounts of the 75 kDa polypeptide are formed. Following loading of erythrocytes with micromolar concentration of Ca2+, in the presence of the ionophore A23187, the native 80 kDa calpain subunit is extensively translocated and retained at the plasma membrane, this process is accompanied by the appearance of only a small amount of the 75 kDa subunit which is released into the soluble fraction of the cells. Following exposure to ÎĽM Ca2+, membrane-bound 80 kDa calpain is converted to the 78 kDa form, this conversion being linearly correlated with the expression of the proteinase activity. Taken together, these results demonstrate that the initial step in calpain activation involves Ca2+-induced translocation to the inner surface of plasma membranes. In the membrane-bound form the native inactive 80 kDa subunit is converted through intramolecular autoproteolysis to a locally active 78 kDa form. Further autoproteolytic intermolecular digestion converts the 78 kDa to the 75 kDa form, no longer being retained by the membrane. This process generates two active forms of calpain, with different intracellular localisations

    Genetic Risk Score to Identify Risk of Venous Thromboembolism in Patients With Cardiometabolic Disease

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    BACKGROUND –: Venous thromboembolism (VTE) is a major cause of cardiovascular morbidity and mortality with a known genetic contribution. We tested the performance of a genetic risk score (GRS) for its ability to predict VTE in three cohorts of patients with cardiometabolic disease. METHODS –: We included patients from the FOURIER, PEGASUS-TIMI 54, and SAVOR-TIMI 53 trials (history of atherosclerosis, myocardial infarction, and diabetes, respectively) who consented for genetic testing and were not on baseline anticoagulation. We calculated a VTE GRS based on 297 SNPs with established genome-wide significance. Patients were divided into tertiles of genetic risk. Cox proportional hazards models were used to calculate hazard ratios for VTE across genetic risk groups. The polygenic risk score was compared to available clinical risk factors (age, obesity, smoking, history of heart failure, diabetes) and common monogenic mutations. RESULTS –: A total of 29,663 patients were included in the analysis with a median follow-up of 2.4 years, of whom 174 had a VTE event. There was a significantly increased gradient of risk across VTE genetic risk tertiles (p-trend <0.0001). After adjustment for clinical risk factors, patients in the intermediate and high genetic risk groups had a 1.88-fold (95% CI 1.23–2.89, p=0.004) and 2.70-fold (95% CI 1.81–4.06, p<0.0001) higher risk of VTE compared to patients with low genetic risk. In a continuous model adjusted for clinical risk factors, each standard deviation increase in the GRS was associated with a 47% (95% CI 29–68) increased risk of VTE (p<0.0001). CONCLUSIONS –: In a broad spectrum of patients with cardiometabolic disease, a polygenic risk score is a strong, independent predictor of VTE after accounting for available clinical risk factors, identifying 1/3 of patients who have a risk of VTE comparable to that seen with established monogenic thrombophilia

    Optical tissue clearing associated with 3D imaging: application in preclinical and clinical studies

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    Understanding the inner morphology of intact tissues is one of the most competitive challenges in modern biology. Since the beginning of the twentieth century, optical tissue clearing (OTC) has provided solutions for volumetric imaging, allowing the microscopic visualization of thick sections of tissue, organoids, up to whole organs and organisms (for example, mouse or rat). Recently, tissue clearing has also been introduced in clinical settings to achieve a more accurate diagnosis with the support of 3D imaging. This review aims to give an overview of the most recent developments in OTC and 3D imaging and to illustrate their role in the field of medical diagnosis, with a specific focus on clinical applications

    Draining Techniques for Cystic Craniopharyngiomas

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    reserved6simixedDelitala, Alberto; Spaziante, Renato; Zona, Gianluigi; Brunori, Andrea; Marruzzo, Daniele; Melloni, IlariaDelitala, Alberto; Spaziante, Renato; Zona, Gianluigi; Brunori, Andrea; Marruzzo, Daniele; Melloni, Ilari

    Effect of mono- or bisegmental lordosizing fusion on short term global and index sagittal balance: a radiographic study

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    Sagittal balance is widely recognized as an important outcome factor in reconstructive spinal surgery for lumbar degenerative conditions. However, its role in short segmental fixation is unknown. The aim of this study is to evaluate the preoperative and short-term postoperative spino-pelvic balance after short (1 or 2 levels) lordosizing lumbar fusion for degenerative disc disease (DDD)

    Effect of mono- or bisegmental lordosizing fusion on short-term global and index sagittal balance: a radiographic study

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    Sagittal balance is widely recognized as an important outcome factor in reconstructive spinal surgery for lumbar degenerative conditions. However, its role in short segmental fixation is unknown. The aim of this study was to evaluate the preoperative and short-term postoperative spino-pelvic balance after short (1 or 2 levels) lordosizing lumbar fusion for degenerative disc disease (DDD)
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