331 research outputs found

    Weak factorization systems and fibrewise regular injectivity for actions of pomonoids on posets

    No full text
    Let S be a pomonoid. In this paper, Pos-S, the category of S-posets and S-poset maps, is considered. One of the main aims of this paper is to draw attention to the notion of weak factorization systems in Pos-S. We show that if S is a pogroup, or the identity element of S is the bottom (or top) element, then (DU,SplitEpi) is a weak factorization system in Pos-S, where DU and SplitEpi are the class of du-closed embedding S-poset maps and the class of all split S-poset epimorphisms, respectively. Among other things, we use a fibrewise notion of complete posets in the category Pos-S/B under a particular case that B has trivial action. We show that every regular injective object in Pos-S/B is topological functor. Finally, we characterize them under a special case, where S is a pogroup

    Evaluation of time in therapeutic range (TTR) in patients with non-valvular atrial fibrillation receiving treatment with warfarin in Tehran, Iran: A cross-sectional study

    Get PDF
    Introduction: Anticoagulant control is assessed by Time in Therapeutic Range (TTR). For a given patient, TTR is defined as the duration of time in which the patient�s International Normalized Ratio (INR) values were within a desired range. Aim: To assess TTR in patients receiving treatment with warfarin for non-valvular atrial fibrillation at a referral center for cardiovascular diseases in Tehran, Iran. Materials and Method: Over 6 months, we enrolled eligible patients presenting to Shaheed Rajaie Hospital in Tehran for regular INR testing. Demographic data, medical history, and current medications were determined for all participants. TTR was assessed by the Rosendaal method. Results: A total of 470 patients (mean age 58.0±14.2 years, 60.2 women) underwent 1450 INR measurements. The mean TTR was calculated as 54.9±11.9. Of the sample patients, 37.3 were in the good control category (TTR > 70), 24.6 were in the intermediate category (50 < TTR < 70), and 38.1 were in the poor control category (TTR < 50). The number of current medications above four was a significant predictor of poor control (OR = 2.06; 95 CI, 1.87, 2.23). The mean TTR of the studied patients (54.9) was below the good control range. Conclusion: The quality of anticoagulant therapy with warfarin in Iranian patients is poorer than that reported in European countries. Based on these results, research considering the causes of poor TTR among Iranian patients is recommended. © 2016, Journal of Clinical and Diagnostic Research. All rights reserved

    A phase II trial of CHOP chemotherapy followed by yttrium 90 ibritumomab tiuxetan (Zevalin) for previously untreated elderly diffuse large B-cell lymphoma patients

    Get PDF
    Background: A prospective, single-arm, open-label, nonrandomized phase II combination chemotherapy with cyclophosphamide, doxorubicin, vincristine, and prednisone (CHOP) plus radioimmunotherapy trial was conducted to evaluate the efficacy and safety in untreated elderly diffuse large B-cell lymphoma (DLBCL) patients. Patients and methods: From February 2005 to April 2006, in our institute we treated 20 eligible elderly (age 6560 years) patients with previously untreated DLBCL using a novel regimen consisting of six cycles of CHOP chemotherapy followed 6-10 weeks later by 90Y ibritumomab tiuxetan. Results: The overall response rate to the entire treatment regimen was 100%, including 95% complete remission (CR) and 5% partial remission. Four (80%) of the five patients who achieved less than a CR with CHOP improved their remission status after radioimmunotherapy. With a median follow-up of 15 months, the 2-year progression-free survival was estimated to be 75%, with a 2-year overall survival of 95%. The 90Y ibritumomab tiuxetan toxicity included grade 653 hematologic toxicity in 12 of 20 patients; the most common grade 653 toxic effects were neutropenia (12 patients) and thrombocytopenia (7 patients). Transfusions of red blood cells and/or platelets were given to one patient. Conclusion: This study has established the feasibility, tolerability, and efficacy of this regimen for elderly patients with DLBCL

    Radiomics and artificial intelligence in prostate cancer: new tools for molecular hybrid imaging and theragnostics

    Full text link
    In prostate cancer (PCa), the use of new radiopharmaceuticals has improved the accuracy of diagnosis and staging, refined surveillance strategies, and introduced specific and personalized radioreceptor therapies. Nuclear medicine, therefore, holds great promise for improving the quality of life of PCa patients, through managing and processing a vast amount of molecular imaging data and beyond, using a multi-omics approach and improving patients' risk-stratification for tailored medicine. Artificial intelligence (AI) and radiomics may allow clinicians to improve the overall efficiency and accuracy of using these "big data" in both the diagnostic and theragnostic field: from technical aspects (such as semi-automatization of tumor segmentation, image reconstruction, and interpretation) to clinical outcomes, improving a deeper understanding of the molecular environment of PCa, refining personalized treatment strategies, and increasing the ability to predict the outcome. This systematic review aims to describe the current literature on AI and radiomics applied to molecular imaging of prostate cancer

    90Y Radioembolization for Hepatic Malignancy in Patients with Previous Biliary Intervention: Multicenter Analysis of Hepatobiliary Infections

    Get PDF
    PurposeTo determine the frequency of hepatobiliary infections after transarterial radioembolization (TARE) with yttrium 90 (90Y) in patients with liver malignancy and a history of biliary intervention.Materials and MethodsFor this retrospective study, records of all consecutive patients with liver malignancy and history of biliary intervention treated with TARE at 14 centers between 2005 and 2015 were reviewed. Data regarding liver function, 90Y dosimetry, antibiotic prophylaxis, and bowel preparation prophylaxis were collected. Primary outcome was development of hepatobiliary infection.ResultsOne hundred twenty-six patients (84 men, 42 women; mean age, 68.8 years) with primary (n = 39) or metastatic (n = 87) liver malignancy and history of biliary intervention underwent 180 procedures with glass (92 procedures) or resin (88 procedures) microspheres. Hepatobiliary infections (liver abscesses in nine patients, cholangitis in five patients) developed in 10 of the 126 patients (7.9%) after 11 of the 180 procedures (6.1%; nine of those procedures were performed with glass microspheres). All patients required hospitalization (median stay, 12 days; range, 2–113 days). Ten patients required percutaneous abscess drainage, three patients underwent endoscopic stent placement and stone removal, and one patient needed insertion of percutaneous biliary drains. Infections resolved in five patients, four patients died (two from infection and two from cancer progression while infection was being treated), and one patient continued to receive suppressive antibiotics. Use of glass microspheres (P = .02), previous liver resection or ablation (P = .02), and younger age (P = .003) were independently predictive of higher infection risk.ConclusionInfectious complications such as liver abscess and cholangitis are uncommon but serious complications of transarterial radioembolization with 90Y in patients with liver malignancy and a history of biliary intervention.© RSNA, 2018Online supplemental material is available for this article

    Variational Methods for Biomolecular Modeling

    Full text link
    Structure, function and dynamics of many biomolecular systems can be characterized by the energetic variational principle and the corresponding systems of partial differential equations (PDEs). This principle allows us to focus on the identification of essential energetic components, the optimal parametrization of energies, and the efficient computational implementation of energy variation or minimization. Given the fact that complex biomolecular systems are structurally non-uniform and their interactions occur through contact interfaces, their free energies are associated with various interfaces as well, such as solute-solvent interface, molecular binding interface, lipid domain interface, and membrane surfaces. This fact motivates the inclusion of interface geometry, particular its curvatures, to the parametrization of free energies. Applications of such interface geometry based energetic variational principles are illustrated through three concrete topics: the multiscale modeling of biomolecular electrostatics and solvation that includes the curvature energy of the molecular surface, the formation of microdomains on lipid membrane due to the geometric and molecular mechanics at the lipid interface, and the mean curvature driven protein localization on membrane surfaces. By further implicitly representing the interface using a phase field function over the entire domain, one can simulate the dynamics of the interface and the corresponding energy variation by evolving the phase field function, achieving significant reduction of the number of degrees of freedom and computational complexity. Strategies for improving the efficiency of computational implementations and for extending applications to coarse-graining or multiscale molecular simulations are outlined.Comment: 36 page

    Ion-Abrasion Scanning Electron Microscopy Reveals Surface-Connected Tubular Conduits in HIV-Infected Macrophages

    Get PDF
    HIV-1-containing internal compartments are readily detected in images of thin sections from infected cells using conventional transmission electron microscopy, but the origin, connectivity, and 3D distribution of these compartments has remained controversial. Here, we report the 3D distribution of viruses in HIV-1-infected primary human macrophages using cryo-electron tomography and ion-abrasion scanning electron microscopy (IA-SEM), a recently developed approach for nanoscale 3D imaging of whole cells. Using IA-SEM, we show the presence of an extensive network of HIV-1-containing tubular compartments in infected macrophages, with diameters of ∼150–200 nm, and lengths of up to ∼5 µm that extend to the cell surface from vesicular compartments that contain assembling HIV-1 virions. These types of surface-connected tubular compartments are not observed in T cells infected with the 29/31 KE Gag-matrix mutant where the virus is targeted to multi-vesicular bodies and released into the extracellular medium. IA-SEM imaging also allows visualization of large sheet-like structures that extend outward from the surfaces of macrophages, which may bend and fold back to allow continual creation of viral compartments and virion-lined channels. This potential mechanism for efficient virus trafficking between the cell surface and interior may represent a subversion of pre-existing vesicular machinery for antigen capture, processing, sequestration, and presentation
    corecore