12 research outputs found

    High-grade astrocytoma with piloid features (HGAP): the Charité experience with a new central nervous system tumor entity

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    Purpose: High-grade astrocytoma with piloid features (HGAP) is a recently described brain tumor entity defined by a specific DNA methylation profile. HGAP has been proposed to be integrated in the upcoming World Health Organization classification of central nervous system tumors expected in 2021. In this series, we present the first single-center experience with this new entity. Methods: During 2017 and 2020, six HGAP were identified. Clinical course, surgical procedure, histopathology, genome-wide DNA methylation analysis, imaging, and adjuvant therapy were collected. Results: Tumors were localized in the brain stem (n = 1), cerebellar peduncle (n = 1), diencephalon (n = 1), mesencephalon (n = 1), cerebrum (n = 1) and the thoracic spinal cord (n = 2). The lesions typically presented as T1w hypo- to isointense and T2w hyperintense with inhomogeneous contrast enhancement on MRI. All patients underwent initial surgical intervention. Three patients received adjuvant radiochemotherapy, and one patient adjuvant radiotherapy alone. Four patients died of disease, with an overall survival of 1.8, 9.1, 14.8 and 18.1 months. One patient was alive at the time of last follow-up, 14.6 months after surgery, and one patient was lost to follow-up. Apart from one tumor, the lesions did not present with high grade histology, however patients showed poor clinical outcomes. Conclusions: Here, we provide detailed clinical, neuroradiological, histological, and molecular pathological information which might aid in clinical decision making until larger case series are published. With the exception of one case, the tumors did not present with high-grade histology but patients still showed short intervals between diagnosis and tumor progression or death even after extensive multimodal therapy

    DiffInfinite: Large Mask-Image Synthesis via Parallel Random Patch Diffusion in Histopathology

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    We present DiffInfinite, a hierarchical diffusion model that generates arbitrarily large histological images while preserving long-range correlation structural information. Our approach first generates synthetic segmentation masks, subsequently used as conditions for the high-fidelity generative diffusion process. The proposed sampling method can be scaled up to any desired image size while only requiring small patches for fast training. Moreover, it can be parallelized more efficiently than previous large-content generation methods while avoiding tiling artefacts. The training leverages classifier-free guidance to augment a small, sparsely annotated dataset with unlabelled data. Our method alleviates unique challenges in histopathological imaging practice: large-scale information, costly manual annotation, and protective data handling. The biological plausibility of DiffInfinite data is validated in a survey by ten experienced pathologists as well as a downstream segmentation task. Furthermore, the model scores strongly on anti-copying metrics which is beneficial for the protection of patient data

    Correction to: Two years later: Is the SARS-CoV-2 pandemic still having an impact on emergency surgery? An international cross-sectional survey among WSES members

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    Background: The SARS-CoV-2 pandemic is still ongoing and a major challenge for health care services worldwide. In the first WSES COVID-19 emergency surgery survey, a strong negative impact on emergency surgery (ES) had been described already early in the pandemic situation. However, the knowledge is limited about current effects of the pandemic on patient flow through emergency rooms, daily routine and decision making in ES as well as their changes over time during the last two pandemic years. This second WSES COVID-19 emergency surgery survey investigates the impact of the SARS-CoV-2 pandemic on ES during the course of the pandemic. Methods: A web survey had been distributed to medical specialists in ES during a four-week period from January 2022, investigating the impact of the pandemic on patients and septic diseases both requiring ES, structural problems due to the pandemic and time-to-intervention in ES routine. Results: 367 collaborators from 59 countries responded to the survey. The majority indicated that the pandemic still significantly impacts on treatment and outcome of surgical emergency patients (83.1% and 78.5%, respectively). As reasons, the collaborators reported decreased case load in ES (44.7%), but patients presenting with more prolonged and severe diseases, especially concerning perforated appendicitis (62.1%) and diverticulitis (57.5%). Otherwise, approximately 50% of the participants still observe a delay in time-to-intervention in ES compared with the situation before the pandemic. Relevant causes leading to enlarged time-to-intervention in ES during the pandemic are persistent problems with in-hospital logistics, lacks in medical staff as well as operating room and intensive care capacities during the pandemic. This leads not only to the need for triage or transferring of ES patients to other hospitals, reported by 64.0% and 48.8% of the collaborators, respectively, but also to paradigm shifts in treatment modalities to non-operative approaches reported by 67.3% of the participants, especially in uncomplicated appendicitis, cholecystitis and multiple-recurrent diverticulitis. Conclusions: The SARS-CoV-2 pandemic still significantly impacts on care and outcome of patients in ES. Well-known problems with in-hospital logistics are not sufficiently resolved by now; however, medical staff shortages and reduced capacities have been dramatically aggravated over last two pandemic years

    Plastic deformation simulation of steel panels

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    This paper presents the FEM analysis of plastic deformation of different steel panels using a spherical indenter. Two experiments were done: first on a simple steel panel and second on a stiffened steel panel, which were subjected to a static plastic deformation produced with help of a spherical indenter. The results of the practical test were compared with the results of numerical simulations, which were accomplished using ANSYS-Static Structural module. The tests were realized using an experimental stand based on a screw press mechanism. The tests consist in vertical displacement of the spherical bulb, which in this way deformed the panel leaning on the stand frame. During the tests were measured the force applied to the indenter, with help of an PLC500 force transducer, and the vertical displacement of the panel in the application point of force, with help of an HBM WA/300 displacement transducer. The results of calculations are presented below as: final deformed models and force-displacement diagrams with the comparison between experiment and numerical simulation. In conclusion of this research the compared results between the experiments and numerical simulations revealed that can be achieved accurate results using FEM analysis for plastic deformation problems, with proper parameters settings

    Numerical Vibro-Acoustic Analysis of a Ship Compartment Structure

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    This paper investigates the vibro-acoustic problems of an elastic compartment structure (wheel house) belonging to a ship, coupled to the enclosed air. The excitations from the structural walls of the room by the sound source cause vibrations throughout the system and noise within the acoustic domain. Due to the coupling between the structural vibrations and acoustic pressure field, these systems are typically referred to as vibro-acoustic systems. The acoustic excitations and vibrations on the structural walls of a ship structure, however, are significantly larger and have a much more significant effect to the structural integrity of the ship. In order to determine whether coupled responses are needed, three frequency analyses have been performed: calculus of the first 5 natural frequencies of the fluid separately, the structure separately, and the fluid-structure coupled system. The wall thickness of the room walls is of 5 mm and made of layered composite. The stress analysis of the model at a highly participating structural mode is performed

    Studies and Research on Maximum Flows of the TrotuĹź River in 1990-2017

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    Research has analyzed components of the climate and hydrological regime on the TrotuĹź River and its tributaries over the past 30 years. The hydrological risk was determined by natural causes, but also by anthropogenic causes. Parameters of hydroclimatic risk are represented of the torrential rainfall, flood flows, high frequency of high flows, high erosion speeds etc. The research revealed that at very low intervals (3-5 years) there were floods with very high flows. Changing the climate regime (precipitation concentration on small days) and the natural relief forms in the hydrographical basin (the Eastern Carpathian Mountains) allowed natural risk to occur in the hydrological regime of the TrotuĹź River. Anthropic factors, in particular, the modification of the leakage coefficient by deforestation of forests and the change of agricultural use of land with large slopes have contributed to the occurrence of anthropogenic risk in the TrotuĹź River basin. Corroboration of the two types of risk, natural and anthropic, has led to a hydrological disaster regime in the TrotuĹź River Basin

    Influenţa factorilor de risc hidroclimatic asupra fenomenului de poluare al râurilor

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    The paper presents an analysis of the river pollution phenomena in the TrotuĹź River Basin. The TrotuĹź River area has been affected by multiple floods over the past 28 years (significant in 2004, 2005, 2011 and 2016). The most important categories of pollutant pressures in the TrotuĹź Hydrographic Basin are punctual, diffuse and hydromorphological. The most significant point sources of pollution in the river basin are of domestic, industrial and agricultural type. The pollutants that affected the watercourses in the TrotuĹź catchment area during the study period were petroleum products (51.2%) and organic substances (21.4%). The remaining 27.4% of pollutants are ammonium, ammonia, hydrogen sulphide, heavy metals, cyanide, urea, detergents, ash, phosphorus, etc

    Studies and Research on Natural and Antropic Risk the Moldova’s Lower Course

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    The paper presents the studies and researches on the natural and anthropic risk parameters on the Moldova riverbed in the Soci area, Iasi County. In this area are located hydrotechnical structures for regulation of the riverbed and shore defence for the protection of the undercrossing of the Timisesti-Iasi adduction pipeline. The theoretical study analyzed hydrological risk parameters (especially liquid and solid flows) recorded over the last 30 years. High flow rates have a high hydroclimatic risk for bed and river construction. Anthropogenic risk parameters were manifested in the morphological modification of the minor riverbed of the Moldova River. An important anthropogenic risk is the uncontrolled exploitation of the ballast in the bed and river banks of Moldova. The effects of this risk contributed to the descent of the bed of the bed at an accelerated pace, along with the erosion of the banks. The accumulation of the effects caused by the natural and the anthropic risks led to important morphological changes in the riverbed of Moldova. These modifications have altered the safety state of the construction of the undercrossing of the Timisesti-Iasi adduction pipeline. The result of the hydrological and also human actions was the degradation of the pipelines until their rupture

    The Quality of Life of Patients with Hereditary Nonpolyposis Colorectal Cancer Undergoing Preoperative Chemoradiation

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    Of all the neoplastic sites, colorectal cancer (CRC) is one of the most common cancers in the family. Studies estimate that approximately 30% of all the CRC cases are a hereditary form of the disease with a potentially high impact on the quality of life (QoL), with a high risk of recurrence, and with bio–psycho–social functioning. The aim of the study was to assess the QoL of colorectal cancer patients with genetic risk by using the European Organisation for Research and Treatment of Cancer (EORTC) questionnaire version QLQ-CR29. Materials and methods: The cross-sectional, single-center study was performed on a group of 32 patients with genetic risk of colorectal cancer, who underwent preoperative chemoradiation and surgery. Results: The series of values for the scores on the symptom scale varied between 15 and 30, and the average level of symptom scores did not differ significantly between gender (22.0 vs. 22.75; p = 0.636), highlighting a moderate impairment of QoL. Scores for the emotional functioning scale were significantly lower in men (10.33 vs. 13.25; p = 0.049), as were the scores for the physical functions (15.67 vs. 19.15; p = 0.039), showing a decrease in QoL. Conclusions: The overall score showed an average QoL in patients with colorectal cancer with genetic risk, highlighting significant differences in psycho-emotional functioning between women and men

    High-grade astrocytoma with piloid features (HGAP): the Charité experience with a new central nervous system tumor entity

    No full text
    Purpose!#!High-grade astrocytoma with piloid features (HGAP) is a recently described brain tumor entity defined by a specific DNA methylation profile. HGAP has been proposed to be integrated in the upcoming World Health Organization classification of central nervous system tumors expected in 2021. In this series, we present the first single-center experience with this new entity.!##!Methods!#!During 2017 and 2020, six HGAP were identified. Clinical course, surgical procedure, histopathology, genome-wide DNA methylation analysis, imaging, and adjuvant therapy were collected.!##!Results!#!Tumors were localized in the brain stem (n = 1), cerebellar peduncle (n = 1), diencephalon (n = 1), mesencephalon (n = 1), cerebrum (n = 1) and the thoracic spinal cord (n = 2). The lesions typically presented as T1w hypo- to isointense and T2w hyperintense with inhomogeneous contrast enhancement on MRI. All patients underwent initial surgical intervention. Three patients received adjuvant radiochemotherapy, and one patient adjuvant radiotherapy alone. Four patients died of disease, with an overall survival of 1.8, 9.1, 14.8 and 18.1 months. One patient was alive at the time of last follow-up, 14.6 months after surgery, and one patient was lost to follow-up. Apart from one tumor, the lesions did not present with high grade histology, however patients showed poor clinical outcomes.!##!Conclusions!#!Here, we provide detailed clinical, neuroradiological, histological, and molecular pathological information which might aid in clinical decision making until larger case series are published. With the exception of one case, the tumors did not present with high-grade histology but patients still showed short intervals between diagnosis and tumor progression or death even after extensive multimodal therapy
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