Draft Genome Sequence of an Escherichia coli O157:H43 Strain Isolated from Cattle

Here we report the draft genome sequence of an Escherichia coli O157:H43 strain, designated T22, with an atypical virulence gene profile and isolated from healthy cattle. T22 produces cytolethal distending toxin V (CDT-V) and belongs to phylogenetic group B1 and sequence type 155 (ST155)

The long polar fimbriae (lpf) operon and its flanking regions in bovine Escherichia coli O157:H43 and STEC O136:H12 strains

Long polar fimbriae (Lpf) are intestinal adhesins and important virulence factors of pathogenic Escherichia coli strains. We cloned and sequenced the lpf2-1 operon (lpf2ABCD) and its flanking regions of an intimin- and Shiga toxin-negative E. coli O157:H43 strain from bovine origin, and also sequenced the lpf2-1 operon of 6 additional atypical O157 bovine Escherichia coli strains of various serotypes Nucleotide sequence comparison of these lpf operons showed sequence conservation as they contain only four polymorphic nucleotide positions. Investigation of these O157 strains as well as 13 Escherichia coli Reference Collection (ECOR) strains carrying the lpf2-1 allele revealed high degree of sequence conservation in the lpf2 flanking regions. The lpf2-1 allele is also present in a bovine Shiga toxin-producing E. coli STEC O136:H12 strain and in vitro adherence assays revealed that the absence of lpf2-1 in this strain did not affect its host cell-binding properties. Our data indicate that lpf2 loci is highly conserved in E. coli isolates, but its role in adherence might be masked by other uncharacterized adhesins

Nukleáris medicina a prosztatarák diagnosztikájában és kezelésében (teranosztika) = Nuclear medicine in the diagnosis and treatment of prostate cancer (theranostics)

Az elmúlt években, évtizedekben a nukleáris medicina hatalmas fejlődésen ment át, számos radiofarmakológiai fejlesztés született, és a hibrid berendezésekkel (PET/CT, PET/MR, SPECT/ CT) végzett vizsgálatok is könnyebben elérhetővé váltak a klinikai gyakorlatban. A nukleáris onkológia egyik legjobban kutatott területe a prosztatarák volt, aminek köszönhetően több új radiofarmakon került forgalomba mind diagnosztikus, mind terápiás célra, ezeket Magyarországon is bevezették, illetve elérhető közelségbe kerültek. A szerzők azokat a – prosztatarák-diagnosztikában és -terápiában használt – nukleáris medicinai módszereket foglalták össze, amelyek a klinikai gyakorlatban a legfontosabbak. = In recent years and decades, nuclear medicine has undergone a huge development, many radiopharmacological developments have been made, and examinations with hybrid equipment (PET/CT, PET/MR, SPECT/CT) have become more easily available in clinical practice. One of the most researched areas of nuclear oncology was prostate cancer, as a result several novel radiopharmaceuticals were put on the market for both diagnostic and therapeutic purposes, and these were also introduced or became achievable in Hungary. The authors have summarized the nuclear medicine methods used in prostate cancer diagnosis and therapy, which are the most important in clinical practice

Loss of the nodule-specific cysteine rich peptide, NCR169, abolishes symbiotic nitrogen fixation in the Medicago truncatula dnf7 mutant

Host compatible rhizobia induce the formation of legume root nodules, symbiotic organs within which intracellular bacteria are present in plant-derived membrane compartments termed symbiosomes. In Medicago truncatula nodules, the Sinorhizobium microsymbionts undergo an irreversible differentiation process leading to the development of elongated polyploid noncultivable nitrogen fixing bacteroids that convert atmospheric dinitrogen into ammonia. This terminal differentiation is directed by the host plant and involves hundreds of nodule specific cysteine-rich peptides (NCRs). Except for certain in vitro activities of cationic peptides, the functional roles of individual NCR peptides in planta are not known. In this study, we demonstrate that the inability of M. truncatula dnf7 mutants to fix nitrogen is due to inactivation of a single NCR peptide, NCR169. In the absence of NCR169, bacterial differentiation was impaired and was associated with early senescence of the symbiotic cells. Introduction of the NCR169 gene into the dnf7-2/NCR169 deletion mutant restored symbiotic nitrogen fixation. Replacement of any of the cysteine residues in the NCR169 peptide with serine rendered it incapable of complementation, demonstrating an absolute requirement for all cysteines in planta. NCR169 was induced in the cell layers in which bacteroid elongation was most pronounced, and high expression persisted throughout the nitrogen-fixing nodule zone. Our results provide evidence for an essential role of NCR169 in the differentiation and persistence of nitrogen fixing bacteroids in M. truncatula

Laminar analysis of the slow wave activity in the somatosensory cortex of anesthetized rats.

Rhythmic slow waves characterize brain electrical activity during natural deep sleep and under anesthesia, reflecting the synchronous membrane potential fluctuations of neurons in the thalamocortical network. Strong evidence indicates that the neocortex plays an important role in the generation of slow wave activity (SWA), however, contributions of individual cortical layers to the SWA generation are still unclear. The anatomically correct laminar profiles of SWA were revealed under ketamine/xylazine anesthesia, with combined local field potential recordings, multiple-unit activity (MUA), current source density (CSD) and time-frequency analyses precisely co-registered with histology. The up-state related negative field potential wave showed the largest amplitude in layer IV, the CSD was largest in layers I and III, while MUA was maximal in layer V, suggesting spatially dissociated firing and synaptic/transmembrane processes in the rat somatosensory cortex. Up-state related firing could start in virtually any layers (III-VI) of the cortex, but were most frequently initiated in layer V. However, in a subset of experiments, layer IV was considerably active in initiating up-state related MUA even in the absence of somatosensory stimulation. Somatosensory stimulation further strengthened up-state initiation in layer IV. Our results confirm that cortical layer V firing may have a major contribution to the up-state generation of ketamine/xylazine-induced SWA, however, thalamic influence through the thalamorecipient layer IV can also play an initiating role, even in the absence of sensory stimulation. This article is protected by copyright. All rights reserved

R18C is a new viable P2-like bacteriophage of rabbit origin infecting Citrobacter rodentium and Shigella sonnei strains

Here we report a novel virulent P2-like bacteriophage R18C isolated from rabbit faeces, which, additionally to Escherichia coli K-12 strains, was able to propagate on Citrobacter rodentium strain ICC169 and a range of Shigella sonnei with high efficiency of plating (EOP). It represents the first lytic bacteriophage originated from rabbit and the first infective P2-like phage of animal origin. In the three characteristic moron-harboring regions of P2-like phages, R18C harbors genes with unknown function, which have been only found in cryptic P2-like prophages up to date