Geospatial data on the sediments of Lake Balaton.

Freshwater lakes in most inhabited areas of the world are threatened by water quality issues. Standard water conservation measures have shown efficiency in the past; however, polluted lakes have only partially recovered from eutrophication. Our knowledge is still incomplete about the sensitivity of these lakes to different anthropogenic sources and to the changes in their internal processes due to global warming. In this article, we present a database comprising sediment data from Lake Balaton (Hungary), which can facilitate further analysis helping to better understand the internal processes and changes occurring in the lake. The published dataset includes the following parameters measured in 4211 lake bed sediment samples: pHKCl, calcium carbonate (CaCO3), organic carbon (Corg), total nitrogen (Ntotal), soluble phosphorus (AL-P2O5) and soluble potassium (AL-K2O), magnesium (Mg2+), zinc (Zn2+), copper (Cu2+) and manganese (Mn2+). We are confident that our database serves as a strong basis for further research relating to freshwater lakes influenced by human activities.

Citrullinated fibrinogen forms densely packed clots with decreased permeability.

BACKGROUND: Fibrin, the main scaffold of thrombi, is susceptible to citrullination by PAD (peptidyl arginine deiminase) 4, secreted from neutrophils during the formation of neutrophil extracellular traps. Citrullinated fibrinogen (citFg) has been detected in human plasma as well as in murine venous thrombi, and it decreases the lysability and mechanical resistance of fibrin clots. OBJECTIVE: To investigate the effect of fibrinogen citrullination on the structure of fibrin clots. METHODS: Fibrinogen was citrullinated with PAD4 and clotted with thrombin. Scanning electron microscopy (SEM) and atomic force microscopy (AFM) were used to measure fiber thickness, fiber height/width ratio, and fiber persistence length in clots containing citFg. Fiber density was measured with laser scanning microscopy (LSM) and permeability measurements were carried out to estimate the porosity of the clots. The intra-fiber structure of fibrin was analyzed with small-angle X-ray scattering (SAXS). RESULTS: SEM images revealed a decrease in the median fiber diameter that correlated with the fraction of citFg in the clot, while the fiber width/length ratio remained unchanged according to AFM. With SAXS we observed that citrullination resulted in the formation of denser clots in line with increased fiber density shown by LSM. The permeability constant of citrullinated fibrin decreased more than 3-fold indicating significantly decreased porosity. SAXS also showed largely preserved periodicity in the longitudinal assembly of fibrin monomers. CONCLUSION: The current observations of thin fibers combined with dense packing and low porosity in the presence of citFg can provide a structural framework for the mechanical fragility and lytic resistance of citrullinated fibrin.

Fibrin to von Willebrand factor ratio in arterial thrombi is associated with plasma levels of inflammatory biomarkers and local abundance of extracellular DNA.

INTRODUCTION: The composition of thrombi determines their structure, mechanical stability, susceptibility to lysis, and consequently, the clinical outcome in coronary artery disease (CAD), acute ischemic stroke (AIS), and peripheral artery disease (PAD). Fibrin forms the primary matrix of thrombi intertwined with DNA, derived from neutrophil extracellular traps (NETs), and von Willebrand factor (VWF) bridging DNA and platelets. Here we examined the relative content of fibrin, DNA and VWF in thrombi and analyzed their interrelations and quantitative associations with systemic biomarkers of inflammation and clinical characteristics of the patients. PATIENTS, METHODS: Thrombi extracted from AIS (n = 17), CAD (n = 18) or PAD (n = 19) patients were processed for scanning electron microscopy, (immune)stained for fibrin, VWF and extracellular DNA. Fibrin fiber diameter, cellular components, fibrin/DNA and fibrin/VWF ratios were measured. RESULTS: Patients' age presented as a strong explanatory factor for a linear decline trend of the VWF content relative to fibrin in thrombi from CAD (adjusted-R2 = 0.43) and male AIS (adjusted-R2 = 0.66) patients. In a subgroup of CAD and PAD patients with dyslipidemia and high (above 80%) prevalence of atherothrombosis a significant correlation was observed between the VWF and DNA content in thrombi (adjusted-R2 = 0.40), whereas a 3.7-fold lower linear regression coefficient was seen in AIS patients, in whom the fraction of thrombi of atherosclerotic origin was 57%. Independently of anatomical location, in patients with atherosclerosis the VWF in thrombi correlated with the plasma C-reactive protein levels. CONCLUSIONS: The observed interrelations between thrombus constituents and systemic inflammatory biomarkers suggest an intricate interplay along the VWF/NET/fibrin axis in arterial thrombosis.

Surveillance of human rotaviruses in 2007-2011, Hungary: exploring the genetic relatedness between vaccine and field strains.

BACKGROUND: The availability of rotavirus vaccines has resulted in an intensification of post vaccine strain surveillance efforts worldwide to gain information on the impact of vaccines on prevalence of circulating rotavirus strains. OBJECTIVES: In this study, the distribution of human rotavirus G and P types in Hungary is reported. In addition, the VP4 and VP7 genes of G1P[8] strains were sequenced to monitor if vaccine-derived strains were introduced and/or some strains/lineages were selected against. STUDY DESIGN: The study was conducted in 8 geographic areas of Hungary between 2007 and 2011. Rotavirus positive stool samples were collected from diarrheic patients mostly <5 years of age. Viral RNA was amplified by multiplex genotyping RT-PCR assay, targeting the medically most important G and P types. When needed, sequencing of the VP7 and VP4 genes was performed. RESULTS: In total, 2380 strains were genotyped. During the 5-year surveillance we observed the dominating prevalence of genotype G1P[8] (44.87%) strains, followed by G4P[8] (23.4%), G2P[4] (14.75%) and G9P[8] (6.81%) genotypes. Uncommon strains were identified in a low percentage of samples (4.12%). Phylogenetic analysis of 318 G1P[8] strains identified 55 strains similar to the Rotarix strain (nt sequence identities; VP7, up to 97.9%; VP4, up to 98.5%) although their vaccine origin was unlikely. CONCLUSIONS: Current vaccines would have protected against the majority of identified rotavirus genotypes. A better understanding of the potential long-term effect of vaccine use on epidemiology and evolutionary dynamics of co-circulating wild type strains requires continuous strain surveillance.

[Post vaccination rotavirus surveillance in Hungary, in 2007]. / Posztvakcinációs rotavírus-surveillance Magyarországon, 2007.

Vaccination is the main strategy to control severe dehydrating gastroenteritis caused by rotaviruses in early childhood. The availability of new generation rotavirus vaccines has led to an intensification of strain surveillance worldwide, in part, to gauge the impact of the possible vaccine-driven immune selection of wild-type rotavirus strains. In the present study, authors describe the strain prevalence data obtained in 2007, with the involvement of different regions of Hungary. Genomic RNA was extracted from rotavirus-positive stool samples collected mainly from children and then subjected to genotyping using multiplex RT-PCR assay. Type-specific primers targeted G1 to G4, G6, G8 to G10, and G12 VP7 specificities, and P[4], P[6], and P[8] to P[11] VP4 specificities were used. Out of 489 rotavirus-positive specimens, collected from 482 patients, 466 and 474 were successfully G and P typed, respectively, and both G and P type specificities could be assigned for 457 strains. Prevalence data showed the predominance of G4P[8] (31.5%) strains, followed by G1P[8] (28.3%), G2P[4] (19.3%), and G9P[8] (10.2%). Minority strains were G1P[4] (0.4%), G2P[8] (1.3%), G3P[9] (0.2%), G4P[6] (0.7%), G6P[9] (0.4%), G8P[8] (0.2%), G9P[4] (0.2%), G9P[6] (0.8%), and G12P[8] (0.4%). Mixed infections were found in 1.2% of the samples, while 4.9% remained partially or fully non-typified. Our data indicate that the antigen specificities of medically important rotavirus strains identified in this 1-year study are well represented in the vaccines available in the pharmaceutical private market in Hungary. Depending on the vaccination coverage achievable in the forthcoming years, the post-vaccination rotavirus strain surveillance may allow us to gain comprehensive information on the impact of rotavirus vaccines on the prevalence of circulating rotavirus strains.

Citrullination: a posttranslational modification in health and disease.

Posttranslational modifications are chemical changes to proteins that take place after synthesis. One such modification, peptidylarginine to peptidylcitrulline conversion, catalysed by peptidylarginine deiminases, has recently received significant interest in biomedicine. Introduction of citrulline dramatically changes the structure and function of proteins. It has been implicated in several physiological and pathological processes. Physiological processes include epithelial terminal differentiation, gene expression regulation, and apoptosis. Rheumatoid arthritis, multiple sclerosis, and Alzheimer's disease are examples of human diseases where protein citrullination involvement has been demonstrated. In this review, we discuss our current understanding on the importance of protein deimination in these processes. We describe the enzymes catalyzing the reaction, as well as their known protein substrates. We review the citrullinated peptide epitopes that are proposed as disease markers, specifically recognized in certain human autoimmune disorders. The potential autopathogenic role of citrullinated epitopes is also discussed.

Serum amyloid P component induces neuronal apoptosis and beta-amyloid immunoreactivity.

Previously we have reported serum amyloid P component (SAP) induced cell death in cerebro-cortical cultures of rat brain. In this paper we studied the types of target cells and the molecular mechanism of SAP-induced cell death. Immuno-electron and light microscopy revealed that SAP penetrates the plasma membrane and translocates selectively into the nuclei of neurons. Neuronal cells with SAP immunoreactivity exhibit the morphological hallmarks of apoptosis in vitro. The apoptotic mechanism of cell death is also supported by the increased Bax/Bcl-2 ratio. In addition to neurotoxic effects, we detected elevated beta-amyloid (Abeta) immunoreactivity following SAP treatment. This study supports the thesis that SAP plays an important role in the pathomechanism of neurodegenerative diseases, including Alzheimer's disease by inducing neuronal apoptosis.