Understanding the dynamics of Toll-like Receptor 5 response to flagellin and its regulation by estradiol

© 2017 The Author(s). Toll-like receptors (TLRs) are major players of the innate immune system. Once activated, they trigger a signalling cascade that leads to NF-ΰ B translocation from the cytoplasm to the nucleus. Single cell analysis shows that NF-ΰ B signalling dynamics are a critical determinant of transcriptional regulation. Moreover, the outcome of innate immune response is also affected by the cross-talk between TLRs and estrogen signalling. Here, we characterized the dynamics of TLR5 signalling, responsible for the recognition of flagellated bacteria, and those changes induced by estradiol in its signalling at the single cell level. TLR5 activation in MCF7 cells induced a single and sustained NF-k B translocation into the nucleus that resulted in high NF-k B transcription activity. The overall magnitude of NF-k B transcription activity was not influenced by the duration of the stimulus. No significant changes are observed in the dynamics of NF-k B translocation to the nucleus when MCF7 cells are incubated with estradiol. However, estradiol significantly decreased NF-k B transcriptional activity while increasing TLR5-mediated AP-1 transcription. The effect of estradiol on transcriptional activity was dependent on the estrogen receptor activated. This fine tuning seems to occur mainly in the nucleus at the transcription level rather than affecting the translocation of the NF-k B transcription factor

Bats host major mammalian paramyxoviruses

The large virus family Paramyxoviridae includes some of the most significant human and livestock viruses, such as measles-, distemper-, mumps-, parainfluenza-, Newcastle disease-, respiratory syncytial virus and metapneumoviruses. Here we identify an estimated 66 new paramyxoviruses in a worldwide sample of 119 bat and rodent species (9,278 individuals). Major discoveries include evidence of an origin of Hendra- and Nipah virus in Africa, identification of a bat virus conspecific with the human mumps virus, detection of close relatives of respiratory syncytial virus, mouse pneumonia- and canine distemper virus in bats, as well as direct evidence of Sendai virus in rodents. Phylogenetic reconstruction of host associations suggests a predominance of host switches from bats to other mammals and birds. Hypothesis tests in a maximum likelihood framework permit the phylogenetic placement of bats as tentative hosts at ancestral nodes to both the major Paramyxoviridae subfamilies (Paramyxovirinae and Pneumovirinae). Future attempts to predict the emergence of novel paramyxoviruses in humans and livestock will have to rely fundamentally on these data

Tumor Volume Estimation and Quasi- Continuous Administration for Most Effective Bevacizumab Therapy

Bevacizumab is an exogenous inhibitor which inhibits the biological activity of human VEGF. Several studies have investigated the effectiveness of bevacizumab therapy according to different cancer types but these days there is an intense debate on its utility. We have investigated different methods to find the best tumor volume estimation since it creates the possibility for precise and effective drug administration with a much lower dose than in the protocol.We have examined C38 mouse colon adenocarcinoma and HT-29 human colorectal adenocarcinoma. In both cases, three groups were compared in the experiments. The first group did not receive therapy, the second group received one 200 μg bevacizumab dose for a treatment period (protocol-based therapy), and the third group received 1.1 μg bevacizumab every day (quasi-continuous therapy). Tumor volume measurement was performed by digital caliper and small animal MRI. The mathematical relationship between MRI-measured tumor volume and mass was investigated to estimate accurate tumor volume using caliper-measured data. A two-dimensional mathematical model was applied for tumor volume evaluation, and tumor- and therapy-specific constants were calculated for the three different groups. The effectiveness of bevacizumab administration was examined by statistical analysis.In the case of C38 adenocarcinoma, protocol-based treatment did not result in significantly smaller tumor volume compared to the no treatment group; however, there was a significant difference between untreated mice and mice who received quasi-continuous therapy (p = 0.002). In the case of HT-29 adenocarcinoma, the daily treatment with one-twelfth total dose resulted in significantly smaller tumors than the protocol-based treatment (p = 0.038). When the tumor has a symmetrical, solid closed shape (typically without treatment), volume can be evaluated accurately from caliper-measured data with the applied two-dimensional mathematical model.Our results provide a theoretical background for a much more effective bevacizumab treatment using optimized administration

Alphacoronaviruses in New World Bats: Prevalence, Persistence, Phylogeny, and Potential for Interaction with Humans

Bats are reservoirs for many different coronaviruses (CoVs) as well as many other important zoonotic viruses. We sampled feces and/or anal swabs of 1,044 insectivorous bats of 2 families and 17 species from 21 different locations within Colorado from 2007 to 2009. We detected alphacoronavirus RNA in bats of 4 species: big brown bats (Eptesicus fuscus), 10% prevalence; long-legged bats (Myotis volans), 8% prevalence; little brown bats (Myotis lucifugus), 3% prevalence; and western long-eared bats (Myotis evotis), 2% prevalence. Overall, juvenile bats were twice as likely to be positive for CoV RNA as adult bats. At two of the rural sampling sites, CoV RNAs were detected in big brown and long-legged bats during the three sequential summers of this study. CoV RNA was detected in big brown bats in all five of the urban maternity roosts sampled throughout each of the periods tested. Individually tagged big brown bats that were positive for CoV RNA and later sampled again all became CoV RNA negative. Nucleotide sequences in the RdRp gene fell into 3 main clusters, all distinct from those of Old World bats. Similar nucleotide sequences were found in amplicons from gene 1b and the spike gene in both a big-brown and a long-legged bat, indicating that a CoV may be capable of infecting bats of different genera. These data suggest that ongoing evolution of CoVs in bats creates the possibility of a continued threat for emergence into hosts of other species. Alphacoronavirus RNA was detected at a high prevalence in big brown bats in roosts in close proximity to human habitations (10%) and known to have direct contact with people (19%), suggesting that significant potential opportunities exist for cross-species transmission of these viruses. Further CoV surveillance studies in bats throughout the Americas are warranted

GaAs-Based Superluminescent Light-Emitting Diodes with 290-nm Emission Bandwidth by Using Hybrid Quantum Well/Quantum Dot Structures

A high-performance superluminescent light-emitting diode (SLD) based upon a hybrid quantum well (QW)/quantum dot (QD) active element is reported and is assessed with regard to the resolution obtainable in an optical coherence tomography system. We report on the appearance of strong emission from higher order optical transition from the QW in a hybrid QW/QD structure. This additional emission broadening method contributes significantly to obtaining a 3-dB linewidth of 290 nm centered at 1200 nm, with 2.4 mW at room temperature

Transcript levels of Toll-Like receptors 5, 8 and 9 correlate with inflammatory activity in Ulcerative Colitis

<p>Abstract</p> <p>Background</p> <p>Dysregulation of innate immune response by Toll-Like Receptors (TLRs) is a key feature in Ulcerative Colitis (UC). Most studies have focused on <it>TLR2, TLR3</it>, and <it>TLR4 </it>participation in UC. However, few studies have explored other TLRs. Therefore, the aim of this study was to evaluate the mRNA profiles of <it>TLR1 to 9 </it>in colonic mucosa of UC patients, according to disease activity.</p> <p>Methods</p> <p>Colonic biopsies were taken from colon during colonoscopy in 51 patients with Ulcerative Colitis and 36 healthy controls. mRNA levels of <it>TLR1 to 9, Tollip</it>, inflammatory cytokines <it>IL6 </it>and <it>TNF </it>were assessed by RT-qPCR with hydrolysis probes. Characterization of <it>TLR9 </it>protein expression was performed by Immunohistochemistry.</p> <p>Results</p> <p>Toll-like receptors <it>TLR8, TLR9</it>, and <it>IL6 </it>mRNA levels were significantly higher in the colonic mucosa from UC patients (both quiescent and active) as compared to healthy individuals (p < 0.04). In the UC patients group the <it>TLR2, TLR4, TLR8 </it>and <it>TLR9 </it>mRNA levels were found to be significantly lower in patients with quiescent disease, as compared to those with active disease (p < 0.05), whereas <it>TLR5 </it>showed a trend (p = 0.06). <it>IL6 </it>and <it>TNF </it>mRNA levels were significantly higher in the presence of active disease and help to discriminate between quiescent and active disease (p < 0.05). Also, <it>IL6 </it>and <it>TNF </it>mRNA positively correlate with TLRs mRNA with the exception for <it>TLR3</it>, with stronger correlations for <it>TLR5, TLR8</it>, and <it>TLR9 </it>(p < 0.0001). <it>TLR9 </it>protein expression was mainly in the lamina propria infiltrate.</p> <p>Conclusions</p> <p>This study demonstrates that <it>TLR2, TLR4, TLR8</it>, and <it>TLR9 </it>expression increases in active UC patients, and that the mRNA levels positively correlate with the severity of intestinal inflammation as well as with inflammatory cytokines.</p

Two Novel Parvoviruses in Frugivorous New and Old World Bats

Bats, a globally distributed group of mammals with high ecological importance, are increasingly recognized as natural reservoir hosts for viral agents of significance to human and animal health. In the present study, we evaluated pools of blood samples obtained from two phylogenetically distant bat families, in particular from flying foxes (Pteropodidae), Eidolon helvum in West Africa, and from two species of New World leaf-nosed fruit bats (Phyllostomidae), Artibeus jamaicensis and Artibeus lituratus in Central America. A sequence-independent virus discovery technique (VIDISCA) was used in combination with high throughput sequencing to detect two novel parvoviruses: a PARV4-like virus named Eh-BtPV-1 in Eidolon helvum from Ghana and the first member of a putative new genus in Artibeus jamaicensis from Panama (Aj-BtPV-1). Those viruses were circulating in the corresponding bat colony at rates of 7–8%. Aj-BtPV-1 was also found in Artibeus lituratus (5.5%). Both viruses were detected in the blood of infected animals at high concentrations: up to 10E8 and to 10E10 copies/ml for Aj-BtPV-1 and Eh-BtPV-1 respectively. Eh-BtPV-1 was additionally detected in all organs collected from bats (brain, lungs, liver, spleen, kidneys and intestine) and spleen and kidneys were identified as the most likely sites where viral replication takes place. Our study shows that bat parvoviruses share common ancestors with known parvoviruses of humans and livestock. We also provide evidence that a variety of Parvovirinae are able to cause active infection in bats and that they are widely distributed in these animals with different geographic origin, ecologies and climatic ranges

Establishment of Fruit Bat Cells (Rousettus aegyptiacus) as a Model System for the Investigation of Filoviral Infection

Marburg virus and several species of Ebola virus are endemic in central Africa and cause sporadic outbreaks in this region with mortality rates of up to 90%. So far, there is no vaccination or therapy available to protect people at risk in these regions. Recently, different fruit bats have been identified as potential reservoirs. One of them is Rousettus aegyptiacus. It seems that within huge bat populations only relatively small numbers are positive for filovirus-specific antibodies or filoviral RNA, a phenomenon that is currently not understood. As a first step towards understanding the biology of filoviruses in bats, we sought to establish a model system to investigate filovirus replication in cells derived from their natural reservoir. Here, we provide the first insights into this topic by monitoring filovirus infection of a Rousettus aegyptiacus derived cell line, R06E. We were able to show that filoviruses propagate well in R06E cells, which can, therefore, be used to investigate replication and transcription of filovirus RNA and to very efficiently perform rescue of recombinant Marburg virus using reverse genetics. These results emphasize the suitability of the newly established bat cell line for filovirus research