3,177 research outputs found
Isolation of three novel rat and mouse papillomaviruses and their genomic characterization.
Despite a growing knowledge about the biological diversity of papillomaviruses (PV), only little is known about non-human PV in general and about PV mice models in particular. We cloned and sequenced the complete genomes of two novel PV types from the Norway rat (Rattus norvegicus; RnPV2) and the wood mouse (Apodemus sylvaticus; AsPV1) as well as a novel variant of the recently described MmuPV1 (originally designated as MusPV) from a house mouse (Mus musculus; MmuPV1 variant). In addition, we conducted phylogenetic analyses using a systematically representative set of 79 PV types, including the novel sequences. As inferred from concatenated amino acid sequences of six proteins, MmuPV1 variant and AsPV1 nested within the Beta+Xi-PV super taxon as members of the Pi-PV. RnPV2 is a member of the Iota-PV that has a distant phylogenetic position from Pi-PV. The phylogenetic results support a complex scenario of PV diversification driven by different evolutionary forces including co-divergence with hosts and adaptive radiations to new environments. PV types particularly isolated from mice and rats are the basis for new animal models, which are valuable to study PV induced tumors and new treatment options
Interaction particles from the surface of the curved pipeline
The interaction of the agglomerated fine dust particles from the surface of the rotary pyleprovoda, given deposit formation evaluation. The interaction of large particles to the surface of the rotary pyleprovoda. The analysis of hydrodynamic phenomena in the means of protection against wear
Different Outcomes of Experimental Hepatitis E Virus Infection in Diverse Mouse Strains, Wistar Rats, and Rabbits
Hepatitis E virus (HEV) is the causative agent of acute hepatitis E in humans in developing countries, but autochthonous cases of zoonotic genotype 3 (HEV-3) infection also occur in industrialized countries. In contrast to swine, rats, and rabbits, natural HEV infections in mice have not yet been demonstrated. The pig represents a well-established large animal model for HEV-3 infection, but a suitable small animal model mimicking natural HEV-3 infection is currently missing. Therefore, we experimentally inoculated C57BL/6 mice (wild-type, IFNAR−/−, CD4−/−, CD8−/−) and BALB/c nude (nu/nu) mice, Wistar rats, and European rabbits with a wild boar-derived HEV-3 strain and monitored virus replication and shedding, as well as humoral immune responses. HEV RNA and anti-HEV antibodies were detected in one and two out of eight of the rats and all rabbits inoculated, respectively, but not in any of the mouse strains tested. Remarkably, immunosuppressive dexamethasone treatment of rats did not enhance their susceptibility to HEV infection. In rabbits, immunization with recombinant HEV-3 and ratHEV capsid proteins induced protection against HEV-3 challenge. In conclusion, the rabbit model for HEV-3 infection may serve as a suitable alternative to the non-human primate and swine models, and as an appropriate basis for vaccine evaluation studies
Identification of the Amino Acids 300–600 of IRS-2 as 14-3-3 Binding Region with the Importance of IGF-1/Insulin-Regulated Phosphorylation of Ser-573
Phosphorylation of insulin receptor substrate (IRS)-2 on tyrosine residues is a key event in IGF-1/insulin signaling and leads to activation of the PI 3-kinase and the Ras/MAPK pathway. Furthermore, phosphorylated serine/threonine residues on IRS-2 can induce 14-3-3 binding. In this study we searched IRS-2 for novel phosphorylation sites and investigated the interaction between IRS-2 and 14-3-3. Mass spectrometry identified a total of 24 serine/threonine residues on IRS-2 with 12 sites unique for IRS-2 while the other residues are conserved in IRS-1 and IRS-2. IGF-1 stimulation led to increased binding of 14-3-3 to IRS-2 in transfected HEK293 cells and this binding was prevented by inhibition of the PI 3-kinase pathway and an Akt/PKB inhibitor. Insulin-stimulated interaction between endogenous IRS-2 and 14-3-3 was observed in rat hepatoma cells and in mice liver after an acute insulin stimulus and refeeding. Using different IRS-2 fragments enabled localization of the IGF-1-dependent 14-3-3 binding region spanning amino acids 300–600. The 24 identified residues on IRS-2 included several 14-3-3 binding candidates in the region 300–600. Single alanine mutants of these candidates led to the identification of serine 573 as 14-3-3 binding site. A phospho-site specific antibody was generated to further characterize serine 573. IGF-1-dependent phosphorylation of serine 573 was reduced by inhibition of PI 3-kinase and Akt/PKB. A negative role of this phosphorylation site was implicated by the alanine mutant of serine 573 which led to enhanced phosphorylation of Akt/PKB in an IGF-1 time course experiment. To conclude, our data suggest a physiologically relevant role for IGF-1/insulin-dependent 14-3-3 binding to IRS-2 involving serine 573
Exceptional Clinical Resistance and Variable Reservoir Competence
Cowpox virus (CPXV) is a zoonotic virus and endemic in wild rodent populations
in Eurasia. Serological surveys in Europe have reported high prevalence in
different vole and mouse species. Here, we report on experimental CPXV
infections of bank voles (Myodes glareolus) from different evolutionary
lineages with a spectrum of CPXV strains. All bank voles, independently of
lineage, sex and age, were resistant to clinical signs following CPXV
inoculation, and no virus shedding was detected in nasal or buccal swabs. In-
contact control animals became only rarely infected. However, depending on the
CPXV strain used, inoculated animals seroconverted and viral DNA could be
detected preferentially in the upper respiratory tract. The highest antibody
titers and virus DNA loads in the lungs were detected after inoculation with
two strains from Britain and Finland. We conclude from our experiments that
the role of bank voles as an efficient and exclusive CPXV reservoir seems
questionable, and that CPXV may be maintained in most regions by other hosts,
including other vole species. Further investigations are needed to identify
factors that allow and modulate CPXV maintenance in bank voles and other
potential reservoirs, which may also influence spill-over infections to
accidental hosts
Secondary contact between diverged host lineages entails ecological speciation in a European hantavirus
The diversity of viruses probably exceeds biodiversity of eukaryotes, but little is known about the origin and emergence of novel virus species. Experimentation and disease outbreak investigations have allowed the characterization of rapid molecular virus adaptation. However, the processes leading to the establishment of functionally distinct virus taxa in nature remain obscure. Here, we demonstrate that incipient speciation in a natural host species has generated distinct ecological niches leading to adaptive isolation in an RNA virus. We found a very strong association between the distributions of two major phylogenetic clades in Tula orthohantavirus (TULV) and the rodent host lineages in a natural hybrid zone of the European common vole (Microtus arvalis). The spatial transition between the virus clades in replicated geographic clines is at least eight times narrower than between the hybridizing host lineages. This suggests a strong barrier for effective virus transmission despite frequent dispersal and gene flow among local host populations, and translates to a complete turnover of the adaptive background of TULV within a few hundred meters in the open, unobstructed landscape. Genetic differences between TULV clades are homogenously distributed in the genomes and mostly synonymous (93.1%), except for a cluster of nonsynonymous changes in the 50 region of the viral envelope glycoprotein gene, potentially involved in host-driven isolation. Evolutionary relationships between TULV clades indicate an emergence of these viruses through rapid differential adaptation to the previously diverged host lineages that resulted in levels of ecological isolation exceeding the progress of speciation in their vertebrate hosts
Tropism of Puumala orthohantavirus and endoparasite coinfection in the bank vole reservoir
In Europe, most cases of human hantavirus disease are caused by Puumala orthohantavirus (PUUV) transmitted by bank voles (Clethrionomys glareolus, syn. Myodes glareolus), in which PUUV causes inconspicuous infection. Little is known about tropism and endoparasite coinfections in PUUV-infected reservoir and spillover-infected rodents. Here, we characterized PUUV tropism, pathological changes and endoparasite coinfections. The voles and some non-reservoir rodents were examined histologically, immunohistochemically, by in situ hybridization, indirect IgG enzyme-linked immunosorbent assay and reverse transcription-polymerase chain reaction. PUUV RNA and anti-PUUV antibodies were detected simultaneously in a large proportion of the bank voles, indicating persistent infection. Although PUUV RNA was not detected in non-reservoir rodents, the detection of PUUV-reactive antibodies suggests virus contact. No specific gross and histological findings were detected in the infected bank voles. A broad organ tropism of PUUV was observed: kidney and stomach were most frequently infected. Remarkably, PUUV was detected in cells lacking the typical secretory capacity, which may contribute to the maintenance of virus persistence. PUUV-infected wild bank voles were found to be frequently coinfected with Hepatozoon spp. and Sarcocystis (Frenkelia) spp., possibly causing immune modulation that may influence susceptibility to PUUV infection or vice versa. The results are a prerequisite for a deeper understanding of virus–host interactions in natural hantavirus reservoirs
Internationale Klassifikation von Gesteinen nach pedologischen Gesichtspunkten
Im Rahmen des europäischen eSOTER Projekts (www.esoter.net) werden neue Me-thoden für die bodenkundlich ausgerichtete Abgrenzung von Landschaften mit GIS-Mo¬dellen entwickelt. Diese basieren im Wesentlichen auf digitalen Relief- und Lithologiedaten. Der Schwerpunkt der BGR-Arbeiten liegt auf der einheitlichen Erfas-sung und Darstellung von Gesteinsinforma¬tionen nach pedologischen Aspekten. Mit diesen Aktivitäten unterstützt die BGR auch ein Projekt des globalen Umweltüberwa-chungssystems GEOSS (Task „Global Soil Data“). Die BGR stellt nunmehr eine Über-arbeitung der FAO-Ausgangsgesteinsklassi¬fikation zur Diskussion
Presence and Diversity of Different Enteric Viruses in Wild Norway Rats (Rattus norvegicus)
Abstract:
Rodents are common reservoirs for numerous zoonotic pathogens, but knowledge about
diversity of pathogens in rodents is still limited. Here, we investigated the occurrence and genetic
diversity of enteric viruses in 51 Norway rats collected in three different countries in Europe. RNA of
at least one virus was detected in the intestine of 49 of 51 animals. Astrovirus RNA was detected
in 46 animals, mostly of rat astroviruses. Human astrovirus (HAstV-8) RNA was detected in one,
rotavirus group A (RVA) RNA was identified in eleven animals. One RVA RNA could be typed as
rat G3 type. Rat hepatitis E virus (HEV) RNA was detected in five animals. Two entire genome
sequences of ratHEV were determined. Human norovirus RNA was detected in four animals
with the genotypes GI.P4-GI.4, GII.P33-GII.1, and GII.P21. In one animal, a replication competent
coxsackievirus A20 strain was detected. Additionally, RNA of an enterovirus species A strain was
detected in the same animal, albeit in a different tissue. The results show a high detection rate and
diversity of enteric viruses in Norway rats in Europe and indicate their significance as vectors for
zoonotic transmission of enteric viruses. The detailed role of Norway rats and transmission pathways
of enteric viruses needs to be investigated in further studies.Peer Reviewe
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