541 research outputs found

    Vanishing world: alkaline, saline lakes in Central Europe and their diatom assemblages

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    European shallow, alkaline, saline lakes are potential indicators of climate change. Diatoms have often been reported as valuable proxies for different kinds of anthropogenic activities. Diatom assemblages and 14 environmental variables from shallow, alkaline lakes from 2 different regions of the Carpathian basin (Europe) were investigated for 3 years to (1) elucidate the physical and chemical parameters and diatom assemblages of these lakes, (2) select the principle variables affecting the diatom communities, and (3) show the relevance of diatoms as ecological bioindicators. Water chemical characteristics of the lakes in the 2 regions differ significantly in anion concentrations (HCO3-;, SO42-;, and Cl-), platinum (Pt) units (colour), and oxygen saturation. Dominance by the stress-tolerant, motile diatom ecological guild, represented mainly by Nitzschia and Navicula species, was characteristic in these saline, turbid environments. Indicator species of the 2 regions were found to be different. Diatom assemblage composition was chiefly determined by conductivity and HCO3-; and SO42-concentrations. Nutrient loads, extreme weather events, and consequences of habitat maintenance management were unequivocally identifiable by variations in the benthic diatom assemblage composition. Diatoms are valuable indicators for assessment of ecological status of these saline, alkaline lakes. Including these organisms in ecological status assessments of inland saline lakes may improve the effectiveness of directives for conservation management and might be useful in preserving these pristine habitats that depend on natural hydrological processes

    Contributions à la connaissance des faunes de Mammifères pléistocènes de la Dépression de Brasov (Roumanie)

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    Die Autoren befassen sich in dieser Arbeit mit der Geologie und der Paläontologie der Becken von Baraolt und Sfintu-Gheorghe, welche zu der im Südosten von Transylvanien (Siebenbürgen) gelegenen Senke von Brasov (Kronstadt) gehören. Diese Senkung tektonischen Ursprungs bildete fast während des ganzen Pleistozäns ein großes Seebecken. Die auf mesozoischem Grund abgelagerten Sedimente wurden in vier Horizonte eingeteilt, welche gleichzeitig ebenso vielen Phasen in der Entwicklung der Becken entsprechen. Die Säugetierfauna dieser Horizonte wurde in drei Hauptkomplexe gruppiert, welche dem Unter-, Mittel- und Oberpleistozän entsprechen. Der erste faunistische Komplex umfaßt zwei Phasen, der zweite drei und der letzte eine einzige Phase.researc

    The kisspeptin-1 receptor antagonist peptide-234 aggravates uremic cardiomyopathy in a rat model

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    Uremic cardiomyopathy is characterized by diastolic dysfunction, left ventricular hypertrophy (LVH), and fibrosis. Dysregulation of the kisspeptin receptor (KISS1R)-mediated pathways are associated with the development of fibrosis in cancerous diseases. Here, we investigated the effects of the KISS1R antagonist peptide-234 (P234) on the development of uremic cardiomyopathy. Male Wistar rats (300–350 g) were randomized into four groups: (i) Sham, (ii) chronic kidney disease (CKD) induced by 5/6 nephrectomy, (iii) CKD treated with a lower dose of P234 ( ip. 13 µg/day), (iv) CKD treated with a higher dose of P234 ( ip. 26 µg/day). Treatments were administered daily from week 3 for 10 days. At week 13, the P234 administration did not influence the creatinine clearance and urinary protein excretion. However, the higher dose of P234 led to reduced anterior and posterior wall thicknesses, more severe interstitial fibrosis, and overexpression of genes associated with left ventricular remodeling ( Ctgf, Tgfb, Col3a1, Mmp9 ), stretch ( Nppa ), and apoptosis ( Bax, Bcl2, Casp7 ) compared to the CKD group. In contrast, no significant differences were found in the expressions of apoptosis-associated proteins between the groups. Our results suggest that the higher dose of P234 hastens the development and pathophysiology of uremic cardiomyopathy by activating the fibrotic TGF-β-mediated pathways

    Ecological and human health risk assessment of polycyclic aromatic hydrocarbons (PAH) in Tigris river near the oil refineries in Iraq

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    Recent Iraqi battles against ISIS in 2014 and 2015 resulted in the destruction or severe damage to several refineries' infrastructure. This, along with other factors, has led to the release and accumulation of a wide range of hazardous chemicals into the environment, for instance, polycyclic aromatic hydrocarbons (PAH). Thus, for the first time, a comprehensive 16 PAHs measurements campaign over the course of six months near the oil refineries along the Tigris River and its estuaries was investigated. The 16 PAHs concentrations in surface water and the sediments for the following oil refineries: Baiji, Kirkuk, Al-Siniyah, Qayyarah, Al-Kasak, Daura, South Refineries Company, and Maysan were examined. The overall findings indicated that the 16 PAHs concentrations ranged from 567.8 to 3750.7 ng/L for water and 5619.2–12795.0 ng/g for sediment. Water samples in South Refineries Company recorded the highest PAH concentrations while Baiji oil refinery registered the highest PAH concentrations in the sediment samples. The percentages of high molecular weight PAH (5–6 rings) in water and sediment samples were the highest, ranging from 49.41% to 81.67% and from 39.06% to 89.39% of total PAH for water and sediment, respectively. The majority of 16 PAHs measured in water and sediment samples of the Tigris River were derived from pyrogenic sources. Based on sediment quality guidelines (SQGs), most sites showed a possible effect range with occasional biological effects of most of the PAH concentrations in all sediments’ samples. The calculated incremental lifetime cancer risk (ILCR) value was high risk with adverse health effects, including cancer

    Total transcriptome analysis of Candida auris planktonic cells exposed to tyrosol

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    Tyrosol, a secondary metabolite of Candida species, regulates fungal morphogenesis, and its application may represent a novel innovative therapy against emerging multi-resistant fungal superbug such as Candida auris. In the current study, the effects of tyrosol on growth, redox homeostasis, intracellular microelement contents and activities of virulence-related enzymes released by C. auris were examined. To gain further information about the effect of tyrosol exposure, we revealed gene transcriptional changes using total transcriptome sequencing (RNA-Seq). At a concentration of 15 mM, tyrosol significantly decrease the growth of fungal cells within 2 h of its addition (5.6 × 107±1.2 × 107 and 2.5 × 107±0.6 × 107 colony forming unit/mL for control and tyrosol-treated cells, respectively). Furthermore, it enhanced the release of reactive oxygen species as confirmed by a dichlorofluorescein (DCF) assay (7.3 ± 1.8 [nmol DCF (OD640)−1] versus 16.8 ± 3.9 [nmol DCF (OD640)−1]), which was coincided with elevated superoxide dismutase, catalase and glutathione peroxidase activities. Tyrosol exerted in a 37%, 25%, 34% and 55% decrease in intracellular manganese, iron, zinc and copper contents, respectively, compared to control cells. The tyrosol treatment led to a 142 and 108 differentially transcripted genes with at least a 1.5-fold increase or decrease in transcription, respectively. Genes related to iron and fatty acid metabolism as well as nucleic acid synthesis were down-regulated, whereas those related to the antioxidative defence, adhesion and oxoacid metabolic processes were up-regulated. This study shows that tyrosol significantly influences growth, intracellular physiological processes and gene transcription in C. auris, which could highly support the development of novel treatment approaches against this important pathogen

    EULAR recommendations for the management of systemic lupus erythematosus : 2023 update

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    To update the EULAR recommendations for the management of systemic lupus erythematosus (SLE) based on emerging new evidence.An international Task Force formed the questions for the systematic literature reviews (January 2018-December 2022), followed by formulation and finalisation of the statements after a series of meetings. A predefined voting process was applied to each overarching principle and recommendation. Levels of evidence and strengths of recommendation were assigned, and participants finally provided their level of agreement with each item.The Task Force agreed on 5 overarching principles and 13 recommendations, concerning the use of hydroxychloroquine (HCQ), glucocorticoids (GC), immunosuppressive drugs (ISDs) (including methotrexate, mycophenolate, azathioprine, cyclophosphamide (CYC)), calcineurin inhibitors (CNIs, cyclosporine, tacrolimus, voclosporin) and biologics (belimumab, anifrolumab, rituximab). Advice is also provided on treatment strategies and targets of therapy, assessment of response, combination and sequential therapies, and tapering of therapy. HCQ is recommended for all patients with lupus at a target dose 5 mg/kg real body weight/day, considering the individual's risk for flares and retinal toxicity. GC are used as 'bridging therapy' during periods of disease activity; for maintenance treatment, they should be minimised to equal or less than 5 mg/day (prednisone equivalent) and, when possible, withdrawn. Prompt initiation of ISDs (methotrexate, azathioprine, mycophenolate) and/or biological agents (anifrolumab, belimumab) should be considered to control the disease and facilitate GC tapering/discontinuation. CYC and rituximab should be considered in organ-threatening and refractory disease, respectively. For active lupus nephritis, GC, mycophenolate or low-dose intravenous CYC are recommended as anchor drugs, and add-on therapy with belimumab or CNIs (voclosporin or tacrolimus) should be considered. Updated specific recommendations are also provided for cutaneous, neuropsychiatric and haematological disease, SLE-associated antiphospholipid syndrome, kidney protection, as well as preventative measures for infections, osteoporosis, cardiovascular disease.The updated recommendations provide consensus guidance on the management of SLE, combining evidence and expert opinion

    Anticipated Impacts of Climate Change on the Structure and Function of Phytobenthos in Freshwater Lakes

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    Climate change threatens surface waters worldwide, especially shallow lakes where one of the expected consequences is a sharp increase in their water temperatures. Phytobenthos is an essential, but still less studied component of aquatic ecosystems, and it would be important to learn more about how global warming will affect this community in shallow lakes. In this research, the effects of different climate change scenarios (SSP2-4.5 and SSP5-8.5, as intermediate and high emission scenarios) on the structure and function of the entire phytobenthos community using species- and trait-based approaches were experimentally investigated in an outdoor mesocosm system. Our results show that the forecasted 3 ◦C increase in temperature will already exert significant impacts on the benthic algal community by (1) altering its species and (2) trait composition (smaller cell size, lower abundance of colonial and higher of filamentous forms); (3) decreasing Shannon diversity; and (4) enhancing the variability of the community. Higher increase in the temperature (+5 ◦C) will imply more drastic alterations in freshwater phytobenthos by (1) inducing very high variability in species composition and compositional changes even in phylum level (towards higher abundance of Cyanobacteria and Chlorophyta at the expense of Bacillariophyta); (2) continuing shift in trait composition (benefits for smaller cell volume, filamentous life-forms, non-motile and weakly attached taxa); (3) further reducing the functional diversity; (4) increasing biofilm thickness (1.4 μm/◦C) and (5) decreasing maximum quantum yield of photosystem II. In conclusion, already the intermediate emission scenario will predictably induce high risk in biodiversity issues, the high emission scenario will imply drastic impacts on the benthic algae endangering even the function of the ecosystem
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