439 research outputs found
Beta-D-glucan in patients with haematological malignancies
(1-3)-beta-D-glucan (BDG) is an almost panfungal marker (absent in zygomycetes and most cryptococci), which can be successfully used in screening and diagnostic testing in patients with haematological malignancies if its advantages and limitations are known. The aim of this review is to report the data, particularly from the last 5 years, on the use of BDG in haematological population. Published data report mainly on the performance of the Fungitellâą assay, although several others are currently available, and they vary in method and cut-off of positivity. The sensitivity of BDG for invasive fungal disease (IFD) in haematology patients seems lower than in other populations, possibly because of the type of IFD (lower sensitivity was found in case of aspergillosis compared to candidiasis and pneumocystosis) or the use of prophylaxis. The specificity of the test can be improved by using two consecutive positive assays and avoiding testing in the case of the concomitant presence of factors associated with false positive results. BDG should be used in combination with clinical assessment and other diagnostic tests, both radiological and mycological, to provide maximum information. Good performance of BDG in cerebrospinal fluid (CSF) has been reported. BDG is a useful diagnostic method in haematology patients, particularly for pneumocystosis or initial diagnosis of invasive fungal infections
Invasive Candida infection: epidemiology, clinical and therapeutic aspects of an evolving disease and the role of rezafungin
Introduction: Invasive Candida Infections (ICIs) have undergone a series of significant epidemiological, pathophysiological, and clinical changes during the last decades, with a shift toward non-albicans species, an increase in the rate of exogenous infections and clinical manifestations ranging from candidemia to an array of highly invasive and life-threatening clinical syndromes. The long-acting echinocandin rezafungin exhibits potent in-vitro activity against most wild-type and azole-resistant Candida spp. including C.auris. Areas covered: The following topics regarding candidemia only and ICIs were reviewed and addressed: i) pathogenesis; ii) epidemiology and temporal evolution of Candida species; iii) clinical approach; iv) potential role of the novel long-acting rezafungin in the treatment of ICIs. Expert opinion: Authorsâ expert opinion focused on considering the potential role of rezafungin in the evolving context of ICIs. Rezafungin, which combines a potent in-vitro activity against Candida species, including azole-resistant strains and C.auris, with a low likelihood of drugâdrug interactions and a good safety profile, may revolutionize the treatment of candidemia/ICI. Indeed, it may shorten the length of hospital stays when clinical conditions allow and extend outpatient access to treatment of invasive candidiasis, especially when prolonged treatment duration is expected
Novel Ir1âxCoxO2 thin films: Growth and characterization
Ir1âxCoxO2 thin films have been prepared by reactive coâsputtering deposition at room temperature. Composition, structure, electronic properties and electric and magnetic behavior have been analyzed by different techniques including XRR, XRD, TEM microscopy, SQUID magnetometry, electrical resistivity and XAS spectroscopy. After annealing, an Ir1âxCoxO2 substitutional solid solution phase with rutile crystal structure was achieved for a wide Co-doping range 0 †x †0.6. Starkly departing from the highly insulating behavior of CoO and Co3O4, the electrical resistivity at room temperature of our films is only slightly higher than that of IrO2. Likewise, our work shows that the magnetic response of the doped films is very similar to that of the paramagnetic parent IrO2. Neither ferromagnetism nor enhanced paramagnetism is observed. XAS spectra indicate a Co3+ oxidation state and, correspondingly, an oxidation state of âŒ5+ for Ir ions in the polycrystalline Ir0.6Co0.4O2 film. By application of sum rules, a 13 % increase in the spinâorbit coupling is found despite the lattice shrinkage causes a detrimental bandwidth broadening
The use of mannan antigen and anti-mannan antibodies in the diagnosis of invasive candidiasis: recommendations from the Third European Conference on Infections in Leukemia
Many drugs are available for the treatment of systemic or superficial mycoses, but only a limited number of them are effective antifungal drugs, devoid of toxic and undesirable side effects. Furthermore, resistance development and fungistatic rather than fungicidal activities represent limitations of current antifungal therapy. Therefore there remains an urgent need for a new generation of antifungal agents. According to a polypharmacological approach, the present work concerns the synthesis and antifungal activity of a set of peptides designed to simultaneously target the fungal cell surface and lanosterol demethylase, a key enzyme involved in ergosterol synthesis. Our peptides include amino acid sequences characteristic of membrane-active antimicrobial peptides (AMP), and due to the presence of His residues, they carry the imidazole ring characteristic of azole compounds. The peptides synthesized by us, were tested against different yeast species, and displayed general antifungal activity, with a therapeutically promising antifungal specificity against Cryptococcus neoformans
Management of patients with lymphoma and COVID-19: Narrative review and evidence-based practical recommendations
Patients with hematologic malignancies can be immunocompromized because of their disease, anti-cancer therapy, and concomitant immunosuppressive treatment. Furthermore, these patients are usually older than 60 years and have comorbidities. For all these reasons they are highly vulnerable to infection with severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) and have an increased risk of developing severe/critical Coronavirus disease 2019 (COVID-19) compared to the general population. Although COVID-19 vaccination has proven effective in reducing the incidence of severe/critical disease, vaccinated patients with lymphoma may not be protected as they often fail to develop a sufficient antiviral immune response. There is therefore an urgent need to address the management of patients with lymphoma and COVID-19 in the setting of the ongoing pandemic. Passive immunization with monoclonal antibodies against SARS-CoV-2 is a currently available complementary drug strategy to active vaccination for lymphoma patients, while monoclonal antibodies and antiviral drugs (remdesivir, ritonavir-boosted nirmatrelvir, and molnupiravir) have proven effective in preventing the progression to severe/critical COVID-19. In this narrative review we present the most recent data documenting the characteristics and outcomes of patients with concomitant lymphoma and COVID-19. Our ultimate goal is to provide practice-oriented guidance in the management of these vulnerable patients from diagnosis to treatment and follow-up of lymphoma. To this purpose, we will first provide an overview of the main data concerning prognostic factors and fatality rate of lymphoma patients who develop COVID-19; the outcomes of COVID-19 vaccination will also be addressed. We will then discuss current COVID-19 prophylaxis and treatment options for lymphoma patients. Finally, based on the literature and our multidisciplinary experience, we will summarize a set of indications on how to manage patients with lymphoma according to COVID-19 exposure, level of disease severity and former history of infection, as typically encountered in clinical practice
Re: "Comparison of antipseudomonal betalactams for febrile neutropenia empiric therapy: systematic review and network metaanalysis" by Horita et al
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AFM Force Spectroscopy and Steered Molecular Dynamics Simulation of Protein Contactin 4
We use a single molecule atomic force spectroscopy combined with the steered molecular dynamics simulation to determine a mechanical behavior of neural cell adhesion protein contactin during its unfolding. Force curves typical for modular proteins were observed, showing at most four unfolding peaks. The analysis of force spectra performed within worm-like chain model of polymer elasticity showed the presence of three unfolding lengths. Small plateaus, most likely resulting from forced transitions within domains were observed for the first time. Steered molecular dynamics simulations help to determine atomistic picture of domain unfolding
Growth, Morphology and Stability of Au in Contact with the Bi2Se3(0001) Surface
We report a combined microscopy and spectroscopy study of Au deposited on the
Bi2Se3(0001) single crystal surface. At room temperature Au forms islands,
according to the Volmer-Weber growth mode. Upon annealing to 100{\deg} C the Au
deposits are not stable and assemble into larger and thicker islands. The
topological surface state of Bi2Se3 is weakly affected by the presence of Au.
Contrary to other metals, such as Ag or Cr, a strong chemical instability at
the Au/Bi2Se3 interface is ruled out. Core level analysis highlights Bi
diffusion toward the surface of Au islands, in agreement with previous
findings, while chemical interaction between Au and atomic Se is limited at the
interfacial region. For the investigated range of Au coverages, the Au/Bi2Se3
heterostructure is inert towards CO and CO2 exposure at low pressure (10-8
mbar) regime
Contribution of Candida biomarkers and DNA detection for the diagnosis of invasive candidiasis in ICU patients with severe abdominal conditions
BACKGROUND: To assess the performance of Candida albicans germ tube antibody (CAGTA), (1âââ3)-Ă-D-glucan (BDG), mannan antigen (mannan-Ag), anti-mannan antibodies (mannan-Ab), and Candida DNA for diagnosing invasive candidiasis (IC) in ICU patients with severe abdominal conditions (SAC). METHODS: A prospective study of 233 non-neutropenic patients with SAC on ICU admission and expected stayââ„â7Â days. CAGTA (cutoff positivityââ„â1/160), BDG (â„80, 100 and 200Â pg/mL), mannan-Ag (â„60Â pg/mL), mannan-Ab (â„10 UA/mL) were measured twice a week, and Candida DNA only in patients treated with systemic antifungals. IC diagnosis required positivities of two biomarkers in a single sample or positivities of any biomarker in two consecutive samples. Patients were classified as neither colonized nor infected (nâ=â48), Candida spp. colonization (nâ=â154) (low-grade, nâ=â130; high-grade, nâ=â24), and IC (nâ=â31) (intra-abdominal candidiasis, nâ=â20; candidemia, nâ=â11). RESULTS: The combination of CAGTA and BDG positivities in a single sample or at least one of the two biomarkers positive in two consecutive samples showed 90.3Â % (95Â % CI 74.2â98.0) sensitivity, 42.1Â % (95Â % CI 35.2â98.8) specificity, and 96.6Â % (95Â % CI 90.5â98.8) negative predictive value. BDG positivities in two consecutive samples had 76.7Â % (95Â % CI 57.7â90.1) sensitivity and 57.2Â % (95Â % CI 49.9â64.3) specificity. Mannan-Ag, mannan-Ab, and Candida DNA individually or combined showed a low discriminating capacity. CONCLUSIONS: Positive Candida albicans germ tube antibody and (1âââ3)-Ă-D-glucan in a single blood sample or (1âââ3)-Ă-D-glucan positivity in two consecutive blood samples allowed discriminating invasive candidiasis from Candida spp. colonization in critically ill patients with severe abdominal conditions. These findings may be helpful to tailor empirical antifungal therapy in this patient population
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