Top PDF Early host responses of seasonal and pandemic influenza A viruses in primary well-differentiated human lung epithelial cells.

Early host responses of seasonal and pandemic influenza A viruses in primary well-differentiated human lung epithelial cells.

Early host responses of seasonal and pandemic influenza A viruses in primary well-differentiated human lung epithelial cells.

Because regulation of innate immunity by viruses is a key determinant of the subsequent host immune response and clinical outcome, we evaluated the cytokine and chemokine secreted apically and basally in wd-NHBE cells. IAV infections lead to a variety of intracellular responses, inducing innate immune signaling cascades which serve as the first line of defense against the invading virus [43–45]. Cytokines and chemokines produced by these pathways play an important role in the production of airway inflammation and recruitment of immune cells to the site of infection. A key finding from our data was the greater levels of basolateral secretion of pro-inflammatory cytokines (IL-6, CCL5, IL-8 and CCL2) by wd-NHBE infected with the lethal KY/180 isolates as compared to KY/136 and BN/59. We are aware of only two studies of IAV infection in primary NHBE cells that have looked at secretion of cytokines and chemokines from both the apical and basal side of the epithelial culture [46,47]. However, these studies were limited to the earliest time points and did not look at the later time points where we saw the greatest differences. We speculate that differences in basolateral signals such as CCL5 from epithelial cells may play a role in the recruitment, activation, and responses elicited by monocytes. Further, the magnitude of the CCL5 response may give rise to differences in outcome [47]. Recently, in mice, apoptosis of virus-infected macrophages was prevented by CCR5/CCL5 [48]. CCL5 has been demonstrated to send an anti-apoptotic signal to the cell via the Akt and Erk1/2 pathways, which could support an increase in survival and scavenging of recruited and resident macrophages.
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Hemagglutinin 222D/G polymorphism facilitates fast intra-host evolution of pandemic (H1N1) 2009 influenza A viruses.

Hemagglutinin 222D/G polymorphism facilitates fast intra-host evolution of pandemic (H1N1) 2009 influenza A viruses.

The observed differences in receptor binding of HA-D222 and HA-G222 variant reflected the biphasic replication kinetics of mpJena/5258 in the upper and lower respiratory tract of BALB/c mice, as well. SAa2-3Gal is abundantly expressed on ciliated epithelial cells in the trachea of BALB/c mice, whereas SAa2- 6Gal expression was sparing observed [46]. In mouse lung, SA2- 3Gal is the main receptor on ciliated and non-ciliated cells of the bronchi and bronchioles. In addition, SAa2-6Gal was detected on pulmonary alveoli. The organ-specific receptor distribution pattern together with the differences in receptor binding of HA- D222 or HA-G222 variant resulted in better replication of HA- D222 variant in the lung and HA-G222 variant in the trachea of mice, respectively. It contributed to the evolutionary advantage of the HA-G222 variant in mouse trachea. In the past, three to ten lung-to-lung passages were required for mouse adaptation of A(H1N1)pdm09 viruses [17–20]. During lung-to-lung passages, tissue specimens were collected on day 4 p.i. or earlier [47–49]. However, according to the results of the present study the increase in the proportion of HA-G222 variant occurred in the lung after day 5 p.i. This gave rise to the difficulty in the isolation of HA- G222 variant and its detection by Sanger sequencing in the lung in the early stage of the disease after infection with Jena/5258. But, further accumulation of HA-G222 (7–27%) during the second lung passage enabled its detection. More sensitive next generation sequencing or pyrosequencing might be helpful to detect the subpopulations in circulating non-human viruses containing mutations and by this manner help to predict severe influenza.
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Systems-level comparison of host-responses elicited by avian H5N1 and seasonal H1N1 influenza viruses in primary human macrophages.

Systems-level comparison of host-responses elicited by avian H5N1 and seasonal H1N1 influenza viruses in primary human macrophages.

pathways governing the production of type I IFN at 6 h post- infection time. Specifically, we note the up-regulation of the NFkB inhibitors NFKBIA and NFKBIZ, and the up-regulation of several negative regulators of the innate sensing receptor retinoic acid- inducible gene 1 (RIG-I)-like receptors (RLRs), including USP18, ISG15, DHX58 and tumor necrosis factor alpha-induced induced protein 3 (TNFAIP3). Our data here suggested that at the early stage after influenza infection, the cells response by up-regulation of the IFN and IFN signaling as part of the antiviral mechanism. Activation of various IFN regulatory mechanisms such as up- regulation of negative regulators, SOCS via JAK-STAT signaling may lead to the suppression of IFN and/or other anti-viral gene expression in the later stage of virus infection and therefore provide the virus with additional time to replicate. The increase in viral load can cause infected cells to produce excessive pro- inflammatory cytokines with the additional infiltration of immune cells and finally lead to severs tissue damage. This may also be true to explain the pathogenicity of 1918 virus which its NS1 gene has suggested to block the IFN-stimulated gene expression during later stage of infection [34].
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Influenza H5N1 and H1N1 virus replication and innate immune responses in bronchial epithelial cells are influenced by the state of differentiation.

Influenza H5N1 and H1N1 virus replication and innate immune responses in bronchial epithelial cells are influenced by the state of differentiation.

Zeng et al. [12] previously reported that IFN-b expression in Calu-3 cells at 24 h post infection with H5N1 was lower and more delayed than seen with seasonal influenza (H3N2). They found that this delayed IFN-b response was associated with delayed induction of interferon regulatory factor-3 nuclear translocation and suggested that H5N1 evades the IFN-b innate host defenses allowing it to replicate more efficiently. Our findings in NHBE cells are in agreement with theirs at 24 h post infection but we find this is associated with lower (not higher) levels of virus replication. Furthermore we find that at 6 h post infection, H5N1 virus induces more IFN-b than H1N1 virus. These apparently contradictory findings may partly reflect the cell type (Calu-3 vs. NHBE) and the extent of cell differentiation in the two experimental models and the time of data collection. Calu-3 is a transformed continuous cell line originally isolated from a human pulmonary adenocarcinoma and they were differentiated in transwell culture inserts for one week only. In contrast, our wd- NHBE cells are primary cells derived from normal human bronchi, and are cultured and differentiated for 21 days in ALI. As shown in figure 1A, NHBE cell differentiation in our hands was not completed after seven days of ALI cultures when compared to day 21 (Figure 1B). Interestingly, studies on the pathogenesis of severe acute respiratory syndrome coronavirus (SARS-CoV) using polarized Calu-3 cells and differentiated human airway epithelial cells [29,30] found that the latter supported a more productive replication of SARs-CoV. Since SARS-CoV infects ciliated cells, this difference was attributed to the lower numbers of ciliated epithelial cells obtained in the polarized Calu-3 cell model [31]. It is possible that the wd-NHBE cell model which recapitulates the morphological and physiological features of the human conducting airway in vivo would be a more representative model to study respiratory infection.
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Viral replication rate regulates clinical outcome and CD8 T cell responses during highly pathogenic H5N1 influenza virus infection in mice.

Viral replication rate regulates clinical outcome and CD8 T cell responses during highly pathogenic H5N1 influenza virus infection in mice.

Since the first recorded infection of humans with H5N1 viruses of avian origin in 1997, sporadic human infections continue to occur with a staggering mortality rate of .60%. Although sustained human-to-human transmission has not occurred yet, there is a growing concern that these H5N1 viruses might acquire this trait and raise the specter of a pandemic. Despite progress in deciphering viral determinants of pathogenicity, we still lack crucial information on virus/immune system interactions pertaining to severe disease and high mortality associated with human H5N1 influenza virus infections. Using two human isolates of H5N1 viruses that differ in their pathogenicity in mice, we have defined mechanistic links among the rate of viral replication, mortality, CD8 T cell responses, and immunopathology. The extreme pathogenicity of H5N1 viruses was directly linked to the ability of the virus to replicate rapidly, and swiftly attain high steady-state titers in the lungs within 48 hours after infection. The remarkably high replication rate of the highly pathogenic H5N1 virus did not prevent the induction of IFN-b or activation of CD8 T cells, but the CD8 T cell response was ineffective in controlling viral replication in the lungs and CD8 T cell deficiency did not affect viral titers or mortality. Additionally, BIM deficiency ameliorated lung pathology and inhibited T cell apoptosis without affecting survival of mice. Therefore, rapidly replicating, highly lethal H5N1 viruses could simply outpace and overwhelm the adaptive immune responses, and kill the host by direct cytopathic effects. However, therapeutic suppression of early viral replication and the associated enhancement of CD8 T cell responses improved the survival of mice following a lethal H5N1 infection. These findings suggest that suppression of early H5N1 virus replication is key to the programming of an effective host response, which has implications in treatment of this infection in humans.
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Pandemic influenza A viruses escape from restriction by human MxA through adaptive mutations in the nucleoprotein.

Pandemic influenza A viruses escape from restriction by human MxA through adaptive mutations in the nucleoprotein.

Since pH1N1 NP is derived from an influenza A virus of the classical swine lineage [10,27], we analyzed the NP sequences of a number (n = 393) of corresponding swine isolates obtained between 1930 and 2012. Amino acids I/V100 were highly conserved (.99%), but D53 and V313 were not present in any of the NP sequences, which instead harbored the avian consensus amino acids at these positions (Table 1). We therefore anticipated that NPs of the classical swine influenza strains would confer less MxA resistance than pH1N1 NP. Indeed, NP of one of the first swine isolates such as A/swine/Iowa/1976/1931 displayed comparatively poor MxA resistance in the H5N1 polymerase reconstitution assay (Figure 5A). Importantly, NP of the classical swine influenza A virus lineage acquired the additional mutations 305K, 351K, 353I and 357K over time (Figure 4), resulting in a cells were transfected with expression plasmids coding for the PB2, PB1 and PA of H5N1, the indicated NP proteins, the firefly luciferase encoding minigenome, increasing amounts of Mx1-coding plasmid and a Renilla-expressing plasmid to normalize variation in transfection efficiency. Polymerase activity (relative activity) in the presence of antivirally inactive Mx1-K49A was used to normalize the data obtained with Mx1. Error bars indicate the standard error of the mean of three independent experiments. Western blot analysis was performed to determine the expression levels of Mx1 and H5N1 NP. (C–E) H5N1 polymerase activity was determined as in (B) after co-transfection of the expression plasmids coding for Mx1 (200 ng) and the indicated NP mutants (100 ng). The polymerase activity (relative activity) observed in the presence of Mx1 was normalized to Mx1- K49A. The resulting relative activity in the presence of either 1918*NP (C–D) or 1918 NP (E) was set to 100%. Western blot analysis shown in panel (E) was performed to determine the expression levels of NP. Error bars indicate the standard error of the mean of three independent experiments. Student’s t-test was performed to determine the P value. *P,0.05, **P,0.01, ***P,0.001; NS, not significant.
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Sorafenib inhibits epithelial-mesenchymal transition through an epigenetic-based mechanism in human lung epithelial cells.

Sorafenib inhibits epithelial-mesenchymal transition through an epigenetic-based mechanism in human lung epithelial cells.

During metastasis, an increasing number of key growth factors have been found to be responsible for driving EMT, of which transforming growth factor-b (TGF-b) is a master inducer [13]. To examine whether sorafenib could impair TGF-b-induced EMT in epithelial cells, we used human A549 epithelial cells, a lung adenocarcinoma cell line that has been extensively used and is an ideal in vitro model for assessing EMT, carcinogenesis and drug metabolism [14]. Alveolar epithelial A549 cells underwent EMT after being exposed to TGF-b1 for 48 h, during which the cells lost their epithelial honeycomb-like morphology and obtained a spindle-like shape (Figure 1A). Along with these morphological alterations, the expression level of the adherens junction protein E- cadherin was decreased, whereas the expression level of the intermediate filament protein fibronectin was up-regulated (Figure 1B). Impressively, the treatment of A549 cells with sorafenib mediated a cellular resistance to EMT, as shown by cellular phenotypic alterations (Figure 1A) and the expression profiles of EMT markers (Figure 1B). We also treated cells with increasing concentrations of sorafenib under TGF-b1 stimulation. As shown in Figure 1C, sorafenib reversed TGF-b1-induced EMT in a dose-dependent manner. In addition, TGF-b1 provoked a marked increase in the migratory capacity of A549 epithelial cells that could also be abolished by sorafenib (Figure S1). Collectively, these data indicate that sorafenib counteracts TGF-b1-induced EMT and cell migration in A549 adenocarcinoma epithelial cells and provide a possible explanation for its effects with regard to tumor control and reduced cancer metastasis.
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Functional genomics highlights differential induction of antiviral pathways in the lungs of SARS-CoV-infected macaques.

Functional genomics highlights differential induction of antiviral pathways in the lungs of SARS-CoV-infected macaques.

In order to examine how gene expression would be influenced by presence of virus, timing after inoculation, and individual animal variation, global expression profiling was performed. Hierarchical clustering methods were used to order rows (genes) and columns (samples) to identify groups of genes or samples with similar expression patterns [33,34]. These data were plotted as a heat map in which each matrix entry represents a gene expression value (Figure 2A). Red corresponds to higher gene expression than that of the controls; green corresponds to lower gene expression. This analysis yielded 2,050 genes with day 1 samples on one side of the heat map and day 4 samples on the other side of the heat map, indicating an influence of timing after inoculation. There are two major roots to the hierarchical dendrogram, with the larger root composed of all the day 1 samples and the three day 4 samples with the highest virus levels. The smaller root is composed of the remaining day 4 samples with the lowest SARS-CoV levels. Although transcriptional profiling shows some variation when comparing samples from the same animal, the underlying gene expression is similar with a reduction in fold change in the ‘‘low’’ samples. These comparisons suggest that both individual animal variation and the ‘‘asynchronous’’ nature of the infection in the animals’ lungs are factors involved in determining tran- scription of cellular genes. To validate that the host response from infected animals comprises a stronger transcriptional profile than individual variation from mock-infected animals, differential gene expression patterns in the separate mock samples were investigated, but only 38 genes were differ- entially expressed (Figure 2B). These results suggest that underlying basal levels of gene transcription do not confound expression levels after infection. Even in a basal state, some low-level lung-to-lung variations were identified within the same animal but not enough to disrupt segregation of lung pieces based on mock-infected animals.
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Human REV3 DNA Polymerase Zeta Localizes to Mitochondria and Protects the Mitochondrial Genome.

Human REV3 DNA Polymerase Zeta Localizes to Mitochondria and Protects the Mitochondrial Genome.

Co-IP assays were accomplished with Rev3 +/+ and 143B cells with or without UV exposure. Co- IP with Rev3 -/- cells were used as negative control. In brief, cells in 100-mm tissue culture dishes were grown for 6 h after treatment with 5 J/m 2 of UV light. Untreated cells were used as controls. For immunoprecipitation, cells were lysed for 8 min on ice with lysis buffer (20 mM Tris-HCl, pH 8; 150 mM NaCl; 0.1% NP-40; and 1X Protease Inhibitor (Thermo Fisher Scientific, Waltham, MA) and the lysate was centrifuged at 4800 rpm for 10 min. Supernatant protein contents were measured with protein assay kits (Bio-Rad Laboratories). Supernatant (250 μg protein) was pre- cleared with Magnetic Protein A Dynabeads (Invitrogen; 35 μL beads/mL lysate) for 1 h and then used for Co-IP with 10 μg of Pol zeta primary antibody. The lysate was incubated with antibody overnight on a rotator at 4°C. Magnetic Protein A Dynabeads were added, and the preparations were incubated for 1 h on a rotator at 4°C. Beads were washed in lysis buffer (five times) and cap- tured with a magnetic separator (Qiagen). Proteins were eluted in SDS sample buffer at 65°C for 10 min and with frequent vortexing. The protein samples were separated by SDS-PAGE on a 10% polyacrylamide gel and electroblotted onto a PVDF membrane. The blots were incubated with specific primary rabbit polyclonal antibodies against POLG1 and POLG2 (gift from Dr. William C. Copeland, NIEHS) and detected with an HRP-conjugated secondary antibody (Vector Labora- tories). Generic ECL reagent kits (GE Healthcare Biosciences) were used for film development.
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Whole-genome analysis of temporal gene expression during early transdifferentiation of human lung alveolar epithelial type 2 cells in vitro.

Whole-genome analysis of temporal gene expression during early transdifferentiation of human lung alveolar epithelial type 2 cells in vitro.

Although the expression changes are not as striking as those of the other candidate genes similarly verified by qRT-PCR, the cellular localization of PTRF/CAVIN-1 changed dramatically from nuclear to cytoplasmic in the early time points of transdifferentiation. PTRF/CAVIN-1 is nuclear as well in young fibroblasts but becomes cytoplasmic during cellular senescence [55]. This suggests that PTRF might play a dual role: as a transcription factor in the nucleus of non-transitioning hAT2 cells and then, during transdifferentiation and upon relocation to the cytoplasm, as being involved in caveolin-1 function. Targeted mutations in PTRF/CAVIN-1 result in lack of caveolae in lung epithelium and, along with increases in insulin and free fatty acid levels, PTRF mutant mice show impaired glucose tolerance and insulin resistance [56,57]. On the cellular level, insulin (a known regulator of the PI3K and mTOR pathways) both changes the localization of PTRF and decreases its expression [58,59], suggesting that the insulin pathway is important for PTRF function. In addition, insulin has been shown to play a role in lung epithelial fluid transport [55,60], whereas caveolin-1 is a negative regulator of epithelial sodium channel (ENaC) function [61], which would be reflective of the AT2 to AT1 cell transdifferentiation process. In further support of this suggestion, cholesterol-chelating agents, which disrupt caveolin-1 transloca- tion, and siRNA knockdown of the caveolin-1 gene both increase SP-C gene expression, while adenovirally-induced overexpression of caveolin-1 reduces SP-C gene expression [62].
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Multifaceted health impacts of Particulate Matter (PM) and its management: An overview

Multifaceted health impacts of Particulate Matter (PM) and its management: An overview

Present part of this review discusses briefly the management options associated with PM pollution. The persistence of air pollutants and the rapid rise in vehicle travel in recent decades have raised concerns within the planning sector (Stone et al., 2007). Harrison and Yin (2000) in their review supported that single major or trace component of the PM is responsible for the adverse health effects. Costa (2004) described the interaction among PM constituents in the light of scientific and regulatory agendas. Ugwuanyi and Obi (2002) used the environmental impact matrices of the patients versus diseases and found that pollution is already affecting the quality of life and productivity of the people (particularly farmers) in Benue state of Nigeria. Due to extreme health impacts of PM, proper caution should be taken in setting its air quality standards (McClellan, 2002).
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The effects of nitric oxide on the immune response during giardiasis

The effects of nitric oxide on the immune response during giardiasis

and secretion. The signaling processes through which NO acts to regulate immune cells are extremely complex and are only just beginning to be revealed, but are largely indirect through generation of reactive nitrogen oxide species that chemically modify enzymes, signaling proteins and transcription factors. The role of NO might depend on the stage of a disease (i.e., early or late disease stages). And for a given cell, the response to NO will depend on its reactivity state and on the microen- vironment as well.
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Causes Morphometric Changes in the Ileal Enterocytes of Chickens

Causes Morphometric Changes in the Ileal Enterocytes of Chickens

Campylobacteriosis is a worldwide foodborne zoonosis disease caused by Campylobacter jejuni. This microorganism is considered a commensal bacterium in chicken hosts. C. jejuni produces epithelial cell modifications and induces a cytokine gene transcription innate immunity repertoire. In the present study, we describe the invasiveness, morphological cellular modifications, and transcript level expressions of innate immune cytokines from C. jejuni-inoculated chicken ileum explants. C. jejuni was internalized by epithelial ileum cells at 15 minutes postinoculation (p.i.) and was detected intracellularly for 4hs (p.i.). Inoculated explants displayed significant increases in cell height. C. jejuni induced a significant elevation of Transforming Growth Factor Beta 3 (TGF-β3) and Interleukin-1β (IL-1β) transcripts. In conclusion, C. jejuni is internalized in explanted epithelial ileum cells, produces morphological cell modifications, and induces gene transcription of both anti-inflammatory and pro-inflammatory cytokines.
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Early and Real-Time Detection of Seasonal Influenza Onset

Early and Real-Time Detection of Seasonal Influenza Onset

less subject to media or pre-emptive searches. On the other hand, when the search volumes are low, it might not have enough power to detect the initial variations. This limitations could be partially circumvented if Google allowed access to the raw absolute number of searches, instead of the normalized and varying version that GT currently offers. And using GFT instead of the more general GT could possibly improve the results even further. However, [33] analy- ses three different USA regions to show that the 2013 updated GFT algorithm misses the onset by at least 2 weeks in 17 out of the 29 seasons (close to 60%) for which they could compare. Searches on Google are likely to vary from country to country, partially explaining its varying success, but it is also possible that the GFT algorithm itself offers poor results, as had already been suggested [32]. Moreover, this service is only available in select countries and its algo- rithm is proprietary, making it difficult to use. Thus, and despite the described limitations, we argue that even if GT might be less than optimal to predict the peak, it does prove to be very useful in detecting the onset of the seasonal influenza epidemic, in most countries.
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Leukemia inhibitory factor in rat fetal lung development

Leukemia inhibitory factor in rat fetal lung development

LIF and LIFRa immunostainings were performed on formalin- fixed and paraffin-embedded lungs of different gestational ages (13.5–21.5dpc). Sections (5 m m) were placed on SuperFrost HPlus slides (Menzel-Glaser, Germany). LIF antibody (sc-1336; Santa Cruz Biotechnology Inc., USA) was used in a 1:50 dilution and LIFRa antibody (sc-659; Santa Cruz Biotechnology Inc.) in a 1:50 dilution. After dewaxing in xylene and rehydration in ethanol, the samples were incubated in 3% hydrogen peroxide in methanol to quench endogenous peroxidase. Antigen retrieval was achieved by boiling in 10 mM citrate buffer followed by cool down at room temperature. Samples were blocked with 5% BSA (Roche, Germany). Incubation of the primary antibody occurred at 4 uC overnight. Negative control reactions included omission of the primary antibody, the simultaneous omission of the primary and secondary antibodies, and a non-immune goat IgG isotype control diluted to a matching concentration as the primary antibody, instead of the primary antibody. Incubation with the goat ImmunoCruz TM Staining System (sc-2053; Santa Cruz Biotech- nology Inc.) or with the UltraVision detection system anti- polyvalent horseradish peroxidase (Lab Vision Corporation, USA) was carried according to manufacturer’s instructions (for LIF and LIFR immunostainings, respectively). To visualize the peroxidase activities in sections, diaminobenzidine tetrahy- drochloride (Dako, Denmark) was used. Sections were counter- stained with hematoxyline. The slides were observed and photographed with Olympus BX61 microscope (Olympus, Japan). The pictures presented are representative of 6 animals (n = 6) and 12 samples for each gestational age, and three independent experiments were performed.
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Human Capital and the Recent Fall of Earnings Inequality in Brazil

Human Capital and the Recent Fall of Earnings Inequality in Brazil

each component to the reduction of inequality, year by year. The table shows that the variance of wages declined by 0.25 between 1995 and 2009, from an initial value of 0.93, that is, a reduction of 26%. Moreover, the reduction of the education and age wage differentials accounts for about 44% of the total drop. Changes in the education and age composition of the workforce explain about eight percent of the change in inequality, as the new generations become increasingly more educated. The contribution of the price effect within-groups is in the range of 70%, the highest amongst all different factors. Finally, had all the other forces remained constant, the higher human capital of the workforce would have contributed to an increase in the overall variance of earnings by about 22%, since inequality is higher among the more educated and
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Dissertação para obtenção do Grau de Mestre em Genética Molecular e Biomedicina Orientadora: Maria Alexandra Núncio de Carvalho Ramos Fernandes, Professora Doutora, FCTUNL Co-orientador: Pedro Miguel Ribeiro Viana Baptista, Professor associado com agregaç

Dissertação para obtenção do Grau de Mestre em Genética Molecular e Biomedicina Orientadora: Maria Alexandra Núncio de Carvalho Ramos Fernandes, Professora Doutora, FCTUNL Co-orientador: Pedro Miguel Ribeiro Viana Baptista, Professor associado com agregaç

phendione (1,10-phenanthroline-5,6-dione), the ligand common to both TS262 and TS265 compounds…………………………………………………………………………………………..…....7 Figure I.6 - Multiple-scale of living biological materials and systems. Biomolecules of living systems and nanoscale materials share the same length scale providing an interface and direct applications of these materials in life sciences............................................................................10 Figure I.7 – AuNPs of various size and shape with potential applications in biomedicine. Small (a) and large (b) nanospheres, (c) nanorods, (d) sharpened nanorods, (e) nanoshells, (f) nanocages/frames, (g) hollow nanospheres, (h) tetrahedra/octahedra/cubes/icosahedra, (i) rhombic dodecahedra, (j) octahedra, (k) concave nanocubes, (l) tetrahexahedra, (m) rhombic dodecahedra, (n) obtuse triangular bipyramids, (o) trisoctahedra, and (p) nanoprisms..............12 Figure I.8 – Adsorption of PEG molecules on an AuNP surface. One end of these molecules contains a thiol which is adsorbed on the gold surface, and the other end holds a carboxyl group that is facing toward the solution. This type of carbonate chains stabilise AuNPs against aggregation and allow their functionalisation with other biomolecules and/or chemotherapeutics......................................................................................................................13 Figure I.9 – Scheme of chemical mechanism for the conjugation of biological molecules (BM) containing an amino group (-NH 2 ) to free carboxyl groups at the end of the stabiliser molecule
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Personal decision-making criteria related to seasonal and pandemic A(H1N1) influenza-vaccination acceptance among French healthcare workers.

Personal decision-making criteria related to seasonal and pandemic A(H1N1) influenza-vaccination acceptance among French healthcare workers.

Our observations demonstrated that vaccination acceptance among paramedical HCW is mainly a self-centered concept. Therefore, approaches aiming at targeting personal benefits of immunization might be more successful than campaigns focused on preventing absenteeism and transmission to patients. Medical HCWs’ decisions were marked by professionalism (being a role model and patient protection). These results plead strongly for campaigns targeting paramedical and medical HCW separately. Professional values develop largely through an informal process of socialization and training, and, thus, cannot be addressed in a vaccination campaign [28]. However, evidence from the medical and sociological literature suggests that the role model could play a pivotal part in changing human behavior [29–30].
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Exposure to ozone modulates human airway protease/antiprotease balance contributing to increased influenza A infection.

Exposure to ozone modulates human airway protease/antiprotease balance contributing to increased influenza A infection.

To dissect specific points in the virus life cycle upstream of viral replication that could determine the role ozone exposure plays in viral susceptibility, which ultimately dictates viral pathogenesis and outcome, we utilized our previously described enzymatic virus-like particle (VLP) assay [6]. Our data demonstrated that ozone exposure significantly increased influenza virus entry. This is consistent with our previous work showing that exposure to other oxidant pollutants and suppression of Nrf2 increases influenza virus entry [6,46]. Similar to these previous studies, data shown here demonstrated that the mechanism(s) through which ozone exposure alters influenza virus entry is mediated by oxidative stress. Since ozone directly interacts with the apical surface of the respiratory epithelium we hypothesize that ozone either directly, or via the induction of biologically active ozone reaction products, modifies either the expression or function of surface proteins, as previously been demonstrated for human surfactant protein A (SP- A) [77]. Among the most prominent proteins on the apical surface potentially regulating infection are the proteases. To date, at least five different proteases have been identified in the airways of animals and humans [78]. Despite many years of effort, the exact protease(s) that activates influenza has yet to be identified. Numerous groups have reported that the family of type II transmembrane serine proteases and trypsin-like proteases are responsible for viral cleavage [26,30,33,79]. Previous studies have examined these proteases in the context of influenza infections, specifically TMPRSS2 and HAT. Although these studies demon- strated that these proteases are capable of cleavage, the experiments were performed in cell lines such as MDCKs [33] or the colorectal adenocarcinoma cell line Caco-2 [32], neither of which are natural target cells for influenza. Since the cellular protease determines the tropism as well as efficiency of viral replication, we utilized fully differentiated human primary nasal epithelial cells (NECs) in this study, a natural host cell for influenza virus. We show that HAT and TMPRSS2 are not only present, but secreted from NECs (Figure 5B), and that ozone exposure enhances the release of the proteases into the apical compartment. This is consistent with reports showing that oxidative stress increases cellular protease activity [38]. Since proteases in the
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Kineret®/IL-1ra blocks the IL-1/IL-8 inflammatory cascade during recombinant Panton Valentine Leukocidin-triggered pneumonia but not during S. aureus infection.

Kineret®/IL-1ra blocks the IL-1/IL-8 inflammatory cascade during recombinant Panton Valentine Leukocidin-triggered pneumonia but not during S. aureus infection.

The current guidelines for the treatment of necrotizing pneumonia are the prompt and aggressive administration of toxin-suppressing antibiotics such as linezolid [23,31,32,33]. Appropriate antibiotic therapy might not be sufficient in such fulminant diseases in which inflammation is intense and at least partly responsible for lung injury [7]. Indeed, numerous deaths have been observed in patients treated in a timely manner with effective antibiotic therapy [32,34]. Adjunctive anti-inflammatory treatment is widely used in bacterial meningitis even though its efficacy might be limited [35]. The use of non-steroidal antiinflammatory drugs in CA pneumonia is associated with a more complicated course [36] and the use of dexamethasone in treating CA pneumonia is still debated [37,38]. Furthermore, CA- pneumonia covers a wide range of diseases in terms of both the causative pathogenic agent and severity, thus highlighting the need to test adjunctive therapy in specific animal models of diseases. Here, we used a rabbit model of pneumonia to test the therapeutic potential of anti-inflammatory drugs. Due to the high sensitivity of rabbit neutrophils to PVL [20] and as demonstrated by others Figure 5. Kineret/IL-1Ra inhibits the IL-1/IL-8 cascade triggered by sequential intratracheal instillation of HKS and rPVL. (A–E) Rabbits were inoculated intratracheally with HKS, 3 h later with rPVL and euthanized 6 h post-HKS instillation. When applicable, Kineret/IL-1Ra was injected IV at 2 h post-HKS and was co-instillated with rPVL. IL-8 levels in BALF (A) or in lung lysates (B) were quantified by ELISA. (C) Gross pathological scoring was performed. (D) The ratio of lung weight to body weight is shown. (E) Total protein levels in BALF were quantified by Bradford assay. (A–B, E) Each point represents the value obtained in the BALF from one lobe or (C, D) the value obtained for one rabbit. (A–E) The geometric mean is shown. Results from two independent experiments (n = 12) are shown.
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