SUBMICRON SIZED SINTERED ODS STEELS PREPARED BY HIGH EFFICIENT ATTRITION MILLING AND SPARK PLASMA SINTERING

ABSTRACTThis paper summarizes recent results for preparation, structural and mechanical investigation of oxide dispersed strengthened steel (ODS). Three commercial steel powders, two austenitic steel and one martensitic powders have been used as starting materials. One of the austenitic powders was used for morphological study during wet milling. The high efficient attrition mills are on the basis of this work assuring grains with nanostructure. The morphological changes during milling steps have been described. It was demonstrated that 4 hours milling in wet atmosphere are enough to realize steel powders with submicron dimensions. An efficient dispersion of nanosized oxides in ODS steels was achieved by employing high efficiency attrition milling. A combined wet and dry milling process of fine ceramic and steel particles has been proposed. Spark Plasma Sintering (SPS) was applied to realize submicron grained steel compacts. Grains with 100 nm mean size have been observed by scanning electron microscopy (SEM) in sintered austenitic ODS. In comparison, the sintered martensitic dry and combined milled ODS microstructure consisted of grain sizes with 100-300 nm in each case.KEYWORDS: ODS Steel, Spark Plasma Sintering (SPS), attrition milling, Nano-oxides, structural and mechanical investigationRESUMECet article résume des résultats récents relatifs à l’élaboration et la caractérisation structurale et mécanique d’un acier renforcé à l'oxyde (nuance appelée souvent ROD/ODS). Trois poudres commerciales d'acier, deux poudres austénitiques et une poudre martensitique ont été utilisées comme matières d’étude. Une des poudres austénitiques a été utilisée pour l'étude morphologique lors du broyage humide. Le broyage à haute efficacité est sur la base de ce travail assurant l’obtention de grains nanostructurés. Les modifications morphologiques au cours des étapes de broyage ont été bien décrites. Il a été démontré que 4 heures de broyage en atmosphère humide sont suffisantes pour réaliser des poudres d'acier de dimensions submicroniques. Une dispersion efficace des nano-oxydes dans les aciers ROD/ODS a été obtenue en utilisant un broyage spécifique. On a proposé un procédé de broyage humide et sec combiné à des particules de céramique et d'acier. La méthode de frittage par étincelle (spark plasma sintering (SPS)) a été appliquée pour élaborer des aciers compacts à grains submicroniques. Des grains ayant une taille moyenne de 100 nm ont été observés par microscopie électronique à balayage (MEB) dans les aciers ROD/ODS austénitiques frittées. En comparaison, la microstructure de l’acier ROD/ODS martensitique frittée a donné des grains de tailles de 100 à 300 nm dans les deux cas de broyage sec et de broyage combiné (humide et sec)

Prevalence of Heart Disease Risk Factors in the Azores

Abstract(157) de Comunicação em Painel apresentada em "81st European Atherosclerosis Society (AES) Congress", 2013, 2-5 Jun, Lyon, France.BACKGROUND and AIMS: In the Azores age adjusted death rates from coronary heart disease (CHD) are two-fold higher than in mainland Portugal. We determined the prevalence of standard and emerging CHD risk factors in 206 female and 146 male Azorean subjects (mean age 41 years)

The acquisition of asserted, presupposed, and pragmatically implied exhaustivity in Hungarian

The paper reports on three experiments in which the exhaustive interpretation of sentences containing the focus particle csak ‘only’, structural focus constructions, and sentences with neutral intonation and word order were investigated. The results obtained not only reveal the developmental trajectory of the adult-like comprehension of each sentence type, but also contribute to the discussion concerning the semantic or pragmatic nature of their exhaustive meaning component. As the three construction types were judged in different ways on a three-point scale, the findings appear to support the hypothesis according to which exhaustivity is part of the asserted content of sentences with csak ‘only’, it is context-independently presupposed in the case of structural focus, and in certain contexts it can arise as an implicature in the case of neutral utterances, as well

Investigation of the Antihypertrophic and Antifibrotic Effects of Losartan in a Rat Model of Radiation-Induced Heart Disease

Radiation-induced heart disease (RIHD) is a potential late side-effect of thoracic radiotherapy resulting in left ventricular hypertrophy (LVH) and fibrosis due to a complex pathomechanism leading to heart failure. Angiotensin-II receptor blockers (ARBs), including losartan, are frequently used to control heart failure of various etiologies. Preclinical evidence is lacking on the anti-remodeling effects of ARBs in RIHD, while the results of clinical studies are controversial. We aimed at investigating the effects of losartan in a rat model of RIHD. Male Sprague-Dawley rats were studied in three groups: (1) control, (2) radiotherapy (RT) only, (3) RT treated with losartan (per os 10 mg/kg/day), and were followed for 1, 3, or 15 weeks. At 15 weeks post-irradiation, losartan alleviated the echocardiographic and histological signs of LVH and fibrosis and reduced the overexpression of chymase, connective tissue growth factor, and transforming growth factor-beta in the myocardium measured by qPCR; likewise, the level of the SMAD2/3 protein determined by Western blot decreased. In both RT groups, the pro-survival phospho-AKT/AKT and the phospho-ERK1,2/ERK1,2 ratios were increased at week 15. The antiremodeling effects of losartan seem to be associated with the repression of chymase and several elements of the TGF-beta/SMAD signaling pathway in our RIHD model.Peer reviewe

Antibiotic-induced release of small extracellular vesicles (exosomes) with surface-associated DNA

Recently, biological roles of extracellular vesicles (which include among others exosomes, microvesicles and apoptotic bodies) have attracted substantial attention in various fields of biomedicine. Here we investigated the impact of sustained exposure of cells to the fluoroquinolone antibiotic ciprofloxacin on the released extracellular vesicles. Ciprofloxacin is widely used in humans against bacterial infections as well as in cell cultures against Mycoplasma contamination. However, ciprofloxacin is an inducer of oxidative stress and mitochondrial dysfunction of mammalian cells. Unexpectedly, here we found that ciprofloxacin induced the release of both DNA (mitochondrial and chromosomal sequences) and DNA-binding proteins on the exofacial surfaces of small extracellular vesicles referred to in this paper as exosomes. Furthermore, a label-free optical biosensor analysis revealed DNA-dependent binding of exosomes to fibronectin. DNA release on the surface of exosomes was not affected any further by cellular activation or apoptosis induction. Our results reveal for the first time that prolonged low-dose ciprofloxacin exposure leads to the release of DNA associated with the external surface of exosomes

Baseline Characteristics and Disease Phenotype In Inflammatory Bowel Disease Results of A Paediatric IBD Cohort.

BACKGROUND AND AIMS Predicting short-term relapses and long-term prognosis is of outmost importance in paediatric inflammatory bowel disease. Our aim was to investigate the short-term disease outcome and medication during the first year in a paediatric incident cohort from Hungary. In addition, association laboratory markers and disease activity indices with short-term disease outcome and medication were analysed. METHODS From January 1, 2008 to December 31, 2010 demographic data and clinical characteristics of newly diagnosed paediatric inflammatory bowel disease patients younger than 18 years of age were prospectively recorded. RESULTS A total of 420 patients were identified [Crohn's disease: 266; ulcerative colitis 124]. Initially, 48% (124/256) of Crohn's disease patients had moderate to severe disease (PCDAI>31), and this rate decreased to 2.1% at one-year follow-up. Proportion of ulcerative colitis patients with moderate to severe disease (PUCAI>35) at diagnosis declined from 57.5% (69/120) to 6.8% at one-year follow-up. Terminal ileal involvement correlated with higher initial CRP (p = 0.021) and initial PCDAI (p = 0.026). In ulcerative colitis, elevated CRP (p = 0.002) was associated with disease extension. CRP and PCDAI at diagnosis were associated with the need for immunomodulators at one year in children with Crohn's disease. Initial CRP was also associated with the need for immunomodulators in patients with ulcerative colitis at one-year follow-up. CONCLUSIONS At diagnosis half of the patients with inflammatory bowel disease had moderate to severe disease and this rate decreased to less than 10% after one year. Initial CRP and PCDAI were related to the need for aggressive therapy in Crohn's disease

Intelligent image-based in situ single-cell isolation

Quantifying heterogeneities within cell populations is important for many fields including cancer research and neurobiology; however, techniques to isolate individual cells are limited. Here, we describe a high-throughput, non-disruptive, and cost-effective isolation method that is capable of capturing individually targeted cells using widely available techniques. Using high-resolution microscopy, laser microcapture microscopy, image analysis, and machine learning, our technology enables scalable molecular genetic analysis of single cells, targetable by morphology or location within the sample.Peer reviewe

Comparison of the antiremodeling effects of losartan and mirabegron in a rat model of uremic cardiomyopathy

Uremic cardiomyopathy is characterized by diastolic dysfunction (DD), left ventricular hypertrophy (LVH), and fibrosis. Angiotensin-II plays a major role in the development of uremic cardiomyopathy via nitro-oxidative and inflammatory mechanisms. In heart failure, the beta-3 adrenergic receptor (beta 3-AR) is up-regulated and coupled to endothelial nitric oxide synthase (eNOS)-mediated pathways, exerting antiremodeling effects. We aimed to compare the antiremodeling effects of the angiotensin-II receptor blocker losartan and the beta 3-AR agonist mirabegron in uremic cardiomyopathy. Chronic kidney disease (CKD) was induced by 5/6th nephrectomy in male Wistar rats. Five weeks later, rats were randomized into four groups: (1) sham-operated, (2) CKD, (3) losartan-treated (10 mg/kg/day) CKD, and (4) mirabegron-treated (10 mg/kg/day) CKD groups. At week 13, echocardiographic, histologic, laboratory, qRT-PCR, and Western blot measurements proved the development of uremic cardiomyopathy with DD, LVH, fibrosis, inflammation, and reduced eNOS levels, which were significantly ameliorated by losartan. However, mirabegron showed a tendency to decrease DD and fibrosis; but eNOS expression remained reduced. In uremic cardiomyopathy, beta 3-AR, sarcoplasmic reticulum ATPase (SERCA), and phospholamban levels did not change irrespective of treatments. Mirabegron reduced the angiotensin-II receptor 1 expression in uremic cardiomyopathy that might explain its mild antiremodeling effects despite the unchanged expression of the beta 3-AR.Peer reviewe

Real-life experience with switching TNF-α inhibitors in ankylosing spondylitis

Objective: The aim of this study was to evaluate the efficacy, reasons for switching and drug survival of TNF-α inhibitors (TNFis) used as first- and second-line drugs in ankylosing spondylitis (AS). Methods: Data on patients suffering from AS and treated with at least one TNFi between November 2005 and 2013 were extracted retrospectively from the database of a single clinical centre. Beside demographic data, the disease activity measured by the Bath Ankylosing Spondylitis Disease Activity Index (BASDAI), the response rates (BASDAI50), reasons for switching and survival curves of TNFis were analysed in general and in subgroups of patients treated with each of the available TNFis. The reasons for switching were defined as inefficacy, side effects of the given drug, patient's request and occurrence of extra-articular manifestations. Results: Altogether, 175 patients were on TNFis and 77 of them received at least two TNFis. The patients' age at the initiation of the first TNFi was higher among switchers compared to non-switchers (42.5 ± 12.6 vs. 38.8 ± 11.2 years, p = 0.049); otherwise, gender, disease duration and initial disease activity had no influence on the risk of switching. The decrease of the BASDAI was similar among non-switchers and switchers using either the first or second TNFi, but the response rates to the first and second TNFi were worse in switchers than in non-switchers. Following the failure of the first TNFi, the retention on therapy was unfavourable, especially in patients on infliximab after 1 year of treatment. The main reason for switching from the first drug was inefficacy. The frequency of side effects that led to switching was higher in the infliximab group than in patients treated with other agents. Conclusion: Although the retention rate to a second-line TNFi was somewhat worse than that to the first-line TNFi, the switching of TNFis is a good therapeutic option in AS patients who failed to respond to the first TNFi. © Springer-Verlag 2014

The effect of COVID-19 vaccination status on all-cause mortality in patients hospitalised with COVID-19 in Hungary during the delta wave of the pandemic

The high mortality of patients with coronavirus disease 2019 (COVID-19) is effectively reduced by vaccination. However, the effect of vaccination on mortality among hospitalised patients is under-researched. Thus, we investigated the effect of a full primary or an additional booster vaccination on in-hospital mortality among patients hospitalised with COVID-19 during the delta wave of the pandemic. This retrospective cohort included all patients (n = 430) admitted with COVID-19 at Semmelweis University Department of Medicine and Oncology in 01/OCT/2021–15/DEC/2021. Logistic regression models were built with COVID-19-associated in-hospital/30 day-mortality as outcome with hierarchical entry of predictors of vaccination, vaccination status, measures of disease severity, and chronic comorbidities. Deceased COVID-19 patients were older and presented more frequently with cardiac complications, chronic kidney disease, and active malignancy, as well as higher levels of inflammatory markers, serum creatinine, and lower albumin compared to surviving patients (all p < 0.05). However, the rates of vaccination were similar (52–55%) in both groups. Based on the fully adjusted model, there was a linear decrease of mortality from no/incomplete vaccination (ref) through full primary (OR 0.69, 95% CI: 0.39–1.23) to booster vaccination (OR 0.31, 95% CI 0.13–0.72, p = 0.006). Although unadjusted mortality was similar among vaccinated and unvaccinated patients, this was explained by differences in comorbidities and disease severity. In adjusted models, a full primary and especially a booster vaccination improved survival of patients hospitalised with COVID-19 during the delta wave of the pandemic. Our findings may improve the quality of patient provider discussions at the time of admission