23 research outputs found
Hfe Deficiency Impairs Pulmonary Neutrophil Recruitment in Response to Inflammation
Regulation of iron homeostasis and the inflammatory response are tightly linked to protect the host from infection. Here we investigate how imbalanced systemic iron homeostasis in a murine disease model of hereditary hemochromatosis (Hfe−/− mice) affects the inflammatory responses of the lung. We induced acute pulmonary inflammation in Hfe−/− and wild-type mice by intratracheal instillation of 20 µg of lipopolysaccharide (LPS) and analyzed local and systemic inflammatory responses and iron-related parameters. We show that in Hfe−/− mice neutrophil recruitment to the bronchoalveolar space is attenuated compared to wild-type mice although circulating neutrophil numbers in the bloodstream were elevated to similar levels in Hfe−/− and wild-type mice. The underlying molecular mechanisms are likely multifactorial and include elevated systemic iron levels, alveolar macrophage iron deficiency and/or hitherto unexplored functions of Hfe in resident pulmonary cell types. As a consequence, pulmonary cytokine expression is out of balance and neutrophils fail to be recruited efficiently to the bronchoalveolar compartment, a process required to protect the host from infections. In conclusion, our findings suggest a novel role for Hfe and/or imbalanced iron homeostasis in the regulation of the inflammatory response in the lung and hereditary hemochromatosis
Acute kidney injury in patients treated with immune checkpoint inhibitors
Background: Immune checkpoint inhibitor-associated acute kidney injury (ICPi-AKI) has emerged as an important toxicity among patients with cancer. Methods: We collected data on 429 patients with ICPi-AKI and 429 control patients who received ICPis contemporaneously but who did not develop ICPi-AKI from 30 sites in 10 countries. Multivariable logistic regression was used to identify predictors of ICPi-AKI and its recovery. A multivariable Cox model was used to estimate the effect of ICPi rechallenge versus no rechallenge on survival following ICPi-AKI. Results: ICPi-AKI occurred at a median of 16 weeks (IQR 8-32) following ICPi initiation. Lower baseline estimated glomerular filtration rate, proton pump inhibitor (PPI) use, and extrarenal immune-related adverse events (irAEs) were each associated with a higher risk of ICPi-AKI. Acute tubulointerstitial nephritis was the most common lesion on kidney biopsy (125/151 biopsied patients [82.7%]). Renal recovery occurred in 276 patients (64.3%) at a median of 7 weeks (IQR 3-10) following ICPi-AKI. Treatment with corticosteroids within 14 days following ICPi-AKI diagnosis was associated with higher odds of renal recovery (adjusted OR 2.64; 95% CI 1.58 to 4.41). Among patients treated with corticosteroids, early initiation of corticosteroids (within 3 days of ICPi-AKI) was associated with a higher odds of renal recovery compared with later initiation (more than 3 days following ICPi-AKI) (adjusted OR 2.09; 95% CI 1.16 to 3.79). Of 121 patients rechallenged, 20 (16.5%) developed recurrent ICPi-AKI. There was no difference in survival among patients rechallenged versus those not rechallenged following ICPi-AKI. Conclusions: Patients who developed ICPi-AKI were more likely to have impaired renal function at baseline, use a PPI, and have extrarenal irAEs. Two-thirds of patients had renal recovery following ICPi-AKI. Treatment with corticosteroids was associated with improved renal recovery
Hladiny T-2 toxinu a jeho metabolitů a výskyt plísní Fusarium v jarním ječmeni v ČR
Mycotoxins have been widely studied by many research groups but further multidisciplinary research is needed to better understand and clarify many issues. This study describes the use of high-performance liquid chroma-tography coupled with ion trap mass spectrometry (HPLC-MS) to measure T-2 toxin and its metabolites, such as HT-2 toxin, neosolaniol (NEO) and diacetoxyscirpenol (DAS), as well as masked glucosylated mycotoxins in Fusarium-infected Czech spring barley. In total, 152 spring barley samples from the 2018 harvest were analyzed by the ELISA screening method for the presence of T-2 toxin. The most contaminated samples (15), which exceeded the recommended maximum level set by the EU for the sum of T-2 and HT-2 toxin in unprocessed cereals (200 mu g/kg), were analyzed by HPLC-MS/MS and microbiological testing. Isolated fungi were evaluated microscopically and identified by polymerase chain reaction (PCR) assays. The prevalence of Fusarium species in spring barley across the Czech Republic in 2018 showed a predominance of F. poae (12 barley samples) and F. tricinctum (9 barley samples). Other strains (F. sporotrichioides and F. langsethiae) were present at a lower frequency, in 1 and 2 samples, respectively. The average concentration of T-2 plus HT-2 toxin was 107.7 mu g/kg, while NEO and DAS were found in a few samples at values close to their limit of quantification. HT-2 glucoside was identified in all samples.Mykotoxiny byly široce studovány mnoha výzkumnými skupinami, ale k lepšímu pochopení a objasnění mnoha problémů je zapotřebí další výzkum. Tato studie popisuje použití vysoce výkonné kapalinové chromatografie spojené s hmotnostní spektrometrií iontové pasti (HPLC-MS) k měření toxinu T-2 a jeho metabolitů, jako je toxin HT-2, neosolaniol (NEO) a diacetoxyscirpenol (DAS)., stejně jako maskované mykotoxiny v Českém jarním ječmeni infikovaném Fusarium. Celkem bylo analyzováno 152 vzorků jarního ječmene ze sklizně 2018 screeningovou metodou ELISA na přítomnost T-2 toxinu. Nejvíce kontaminované vzorky, které překračovaly doporučenou maximální úroveň stanovenou EU pro sumu T-2 a HT-2 toxinu v nezpracovaných obilovinách (200 ug/kg), byly analyzovány pomocí HPLC-MS/MS a mikrobiologické testování. Izolované houby byly hodnoceny mikroskopicky a identifikovány pomocí polymerázové řetězové reakce (PCR). Prevalence druhů Fusarium v jarním ječmeni na území ČR v roce 2018 vykázala převahu F. poae (12 vzorků ječmene) a F. tricinctum (9 vzorků ječmene). Ostatní kmeny (F. sporotrichioides a F. langsethiae) byly přítomny v nižší frekvenci, v 1 resp. 2 vzorcích. Průměrná koncentrace toxinu T-2 plus HT-2 byla 107,7 ug/kg, zatímco NEO a DAS byly nalezeny v několika vzorcích v hodnotách blízkých jejich limitu kvantifikace. HT-2 glukosid byl identifikován ve všech vzorcích
From T-coalgebras to filter structures and transition systems
Abstract. For any set-endofunctor T: Set → Set there exists a largest subcartesian transformation µ to the filter functor F: Set → Set. Thus we can associate with every T-coalgebra A a certain filter-coalgebra AF. Precisely, when T weakly preserves preimages, µ is natural, and when T weakly preserves intersections, µ factors through the covariant powerset functor P, thus providing for every T-coalgebra A a Kripke structure AP. The paper characterizes weak preservation of preimages, of intersections, and preservation of both preimages and intersections by a functor T via the existence of transformations from T to either F or P. Moreover, we define for arbitrary T-coalgebras A a next-time operator ○A with associated modal operators ✷ and ✸ and relate their properties to weak limit preservation properties of T. In particular, for any T-coalgebra A there is a transition system K with ○A = ○K if and only if T weakly preserves intersections. 1
Arthralgia Induced by BRAF Inhibitor Therapy in Melanoma Patients
Introduction: BRAF inhibitors (BRAFi), commonly used in BRAF-mutated metastatic melanoma (MM) treatment, frequently cause arthralgia. Although this is one of the most common side effects, it has not been characterized yet. Methods: We retrospectively included all patients treated with BRAFi +/− MEK inhibitors (MEKi) for MM at the National Center for Tumor Diseases (Heidelberg) between 2010 and 2018 and reviewed patient charts for the occurrence and management of arthralgia. The evaluation was supplemented by an analysis of frozen sera. Results: We included 154 patients (63% males); 31% (48/154) of them reported arthralgia with a median onset of 21 days after the start of the therapy. Arthralgia mostly affected small joints (27/36, 75%) and less frequently large joints (19/36, 53%). The most commonly affected joints were in fingers (19/36, 53%), wrists (16/36, 44%), and knees (12/36, 33%). In 67% (24/36) of the patients, arthralgia occurred with a symmetrical polyarthritis, mainly of small joints, resembling the pattern typically observed in patients affected by rheumatoid arthritis (RA), for which a role of the MAPK signaling pathway was previously described. Patients were negative for antinuclear antibodies, anti-citrullinated protein antibodies, and rheumatoid factor; arthritis was visible in 10 of 13 available PET–CT scans. The development of arthralgia was linked to better progression-free survival and overall survival. Conclusion: Arthralgia is a common side effect in patients receiving BRAFi +/− MEKi therapy and often presents a clinical pattern similar to that observed in RA patients. Its occurrence was associated with longer-lasting tumor control
mRNA expression of selected inflammatory mediators in lung samples of female <i>Hfe<sup>LysMCre</sup></i> mice.
<p>qPCR results are shown as relative mRNA expression normalized to GAPDH-expression. n = 4–15 mice per group. The affiliation to functional annotation groups is indicated by brackets. An overlap of bracket indicates the affiliation of the respective inflammatory mediators to more than one functional annotation group. Genes that differed significantly in expression between <i>Hfe<sup>LysMCre</sup></i> (−) and <i>Hfe<sup>LysMCre</sup></i> (+) mice in either vehicle- or LPS-treated groups are highlighted in grey and bold letters. <sup>‡</sup><i>P</i><0.05 versus <i>Hfe<sup>LysMCre</sup></i> (−) control mice; <sup>★</sup><i>P</i><0.05 and <sup>★★</sup><i>P</i>≤0.005 versus <i>Hfe<sup>LysMCre</sup></i> (−) control mice; <sup>†</sup><i>P</i><0.05 and <sup>††</sup><i>P</i>≤0.005 versus <i>Hfe<sup>LysMCre</sup></i> (+) control mice; <sup>⧫</sup><i>P</i><0.05 versus LPS-treated <i>Hfe<sup>LysMCre</sup></i> (−) mice.</p
Plasma iron and non-heme tissue iron content in female wild-type, <i>Hfe<sup>−/−</sup></i> and <i>Hfe<sup>LysMCre</sup></i> mice.
<p>Plasma iron in µg/dL, non-heme tissue iron content in µg iron/g dry tissue.</p><p>(A) Female wild-type and <i>Hfe<sup>−/−</sup></i> mice. n = 5–7 per group.</p>‡<p><i>P</i>≤0.005 versus WT control mice;</p>⧫<p><i>P</i>≤0.001 versus LPS-treated WT mice.</p><p>(B) <i>Hfe<sup>LysMCre</sup></i> mice. Vehicle-treated groups: n = 4–5 per group; LPS-treated groups: n = 9–15 per group.</p
Cytokine protein levels in female wild-type, <i>Hfe<sup>−/−</sup></i> and <i>Hfe<sup>LysMCre</sup></i> mice.
<p>Cytokine protein levels are represented by the fluorescence intensity (FI) as assessed by a Multiplex bead-array based technology assay.</p><p>(A) Female wild-type and <i>Hfe<sup>−/−</sup></i> mice. n = 5–7 per group.</p>★<p><i>P</i><0.05 and <sup>★★</sup><i>P</i><0.01 versus WT control mice;</p>†<p><i>P</i><0.05 and <sup>††</sup><i>P</i><0.01 versus <i>Hfe<sup>−/−</sup></i> control mice;</p>⧫<p><i>P</i><0.05 versus LPS-treated WT mice. (B) <i>Hfe<sup>LysMCre</sup></i> mice. Vehicle-treated groups: n = 4–5 per group; LPS-treated groups: n = 9–15 per group.</p>★<p><i>P</i><0.01 versus <i>Hfe<sup>LysMCre</sup></i> (−) control mice;</p>†<p><i>P</i><0.05 versus <i>Hfe<sup>LysMCre</sup></i> (+) control mice.</p
Computerized analysis of cytoplasmic Prussian blue (PB) stained AM.
<p>Analysis of iron deposits in AM and cell size as a surrogate parameter for cell activation of AM obtained from female wild-type and <i>Hfe<sup>−/−</sup></i> mice and <i>Hfe<sup>LysMCre</sup></i> mice at 4 h after intratracheal instillation of vehicle or 20 µg LPS. (A) PB-stained iron deposits in AM of female wild-type and <i>Hfe<sup>−/−</sup></i> mice. <sup>‡</sup><i>P</i><0.05 and <sup>★</sup><i>P</i>≤0.001 versus WT control mice; <sup>†</sup><i>P</i><0.005 versus <i>Hfe<sup>−/−</sup></i> control mice. (B) AM size in female wild-type and <i>Hfe<sup>−/−</sup></i> mice. n = 5–7 per group. <sup>★</sup><i>P</i>≤0.001 versus WT control mice; <sup>†</sup><i>P</i><0.005 versus <i>Hfe<sup>−/−</sup></i> control mice. (C) PB-stained iron deposits in AM of <i>Hfe<sup>LysMCre</sup></i> mice. <sup>★</sup><i>P</i>≤0.001 versus <i>Hfe<sup>LysMCre</sup></i> (−) control mice; <sup>†</sup><i>P</i><0.001 versus <i>Hfe<sup>LysMCre</sup></i> (+) control mice. (D) AM size in <i>Hfe<sup>LysMCre</sup></i> mice. n = 4–15 per group. <sup>†</sup><i>P</i><0.05 versus <i>Hfe<sup>LysMCre</sup></i> (+) control mice.</p
Attenuated inflammatory cell counts in the BAL of wild-type and <i>Hfe<sup>−/−</sup></i> mice.
<p>BAL obtained 4 h after intratracheal instillation of vehicle or 20 µg LPS. (A) Female wild-type and <i>Hfe<sup>−/−</sup></i> mice. n = 5–7 per group. <sup>★</sup><i>P</i><0.001 versus WT control mice; <sup>¶</sup><i>P</i><0.05 and <sup>†</sup><i>P</i><0.001 versus <i>Hfe<sup>−/−</sup></i> control mice; <sup>⧫</sup><i>P</i><0.005 versus LPS-treated WT mice. (B) Male wild-type and <i>Hfe<sup>−/−</sup></i> mice. n = 9–11 per group. <sup>★</sup><i>P</i>≤0.001 versus WT control mice; <sup>‡</sup><i>P</i><0.05 and <sup>†</sup><i>P</i><0.005 versus <i>Hfe<sup>−/−</sup></i> control mice; <sup>⧫</sup><i>P</i><0.005 versus LPS-treated WT mice. Mac. = macrophages; PMN = polymorphonuclear leukocytes/neutrophils; Eos. = eosinophils; Lymph. = lymphocytes. (C–F) Representative images of BAL cytospin slides obtained from WT and <i>Hfe<sup>−/−</sup></i> mice (females). MayGrünwald-Giemsa stain, images obtained at 400× magnification. Scale bars, 20 µm.</p