Top PDF IRF-3, IRF-5, and IRF-7 coordinately regulate the type I IFN response in myeloid dendritic cells downstream of MAVS signaling.

IRF-3, IRF-5, and IRF-7 coordinately regulate the type I IFN response in myeloid dendritic cells downstream of MAVS signaling.

IRF-3, IRF-5, and IRF-7 coordinately regulate the type I IFN response in myeloid dendritic cells downstream of MAVS signaling.

To test this, we inhibited type I IFN signaling in DKO cells using an IFNAR-blocking monoclonal antibody (MAR1-5A3, [50]) and used qRT-PCR to measure gene induction in response to WNV- NY infection (Figure 6D). As expected, the IFNAR-blocking antibody prevented induction of Oas1a, a known IFN-dependent ISG [15], but did not impair induction of Ifnb. Ccl5 and Tnf were induced too weakly to observe differences between the IFNAR- blocking and control MAbs. However, the IFNAR-blocking antibody abolished induction of Cxcl10, Rsad2, Ifit1, and Ifit2, even though these genes are considered to be IFN-independent [14,15] and were induced in Ifnar 2/2 mDC (Figure 5C). Collectively, these results suggest that IRF-5 contributes to the induction of IFN-b expression after WNV infection in mDC, but does not induce ISG expression directly. To further define the contribution of IRF-5 to IFN and ISG induction in mDC, we infected WT, Irf5 2/2 , and DKO mDC with WNV (Figure 6E) and WT, Irf5 2/2 , DKO, and TKO cells with Sendai virus (SeV), a negative sense RNA paramyxovirus (Figure 6F) and measured gene expression by qRT-PCR. We found no change in the induction of Ifnb, Oas1a, Rsad2, or Cxcl10 in Irf5 2/2 mDC compared to WT cells (P.0.05), indicating that loss of IRF-5 alone in mDCs is not sufficient to impact the antiviral response, analogous to results seen with IRF-3 [21]. Consistent with this observation, we observed no significant difference in WNV-NY replication between Irf5 2/2 and WT mDC (P.0.05) (Figure 6G). Although DKO mDC retained intact IFN and ISG responses after WNV infection, this pattern surprisingly was not observed following SeV infection: the induced expression of several ISGs (Oas1a, Rsad2, and Cxcl10) was lost in both DKO and TKO mDC. While our results with DKO and TKO cells after WNV infection establish that IRF-5 contributes to the type I IFN response in mDCs, the critical nature of the IFN induction pathways in these key sentinel cells may have resulted in the maintenance of redundant signaling pathways to sustain antiviral gene programs. Indeed, the distinct ISG induction phenotypes after WNV and SeV infection in DKO and TKO mDCs suggest that activation of these parallel pathways may differ among diverse viruses.
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Fatores Reguladores de Interferon (IRFs) em pacientes com Síndrome Mielodisplásica

Fatores Reguladores de Interferon (IRFs) em pacientes com Síndrome Mielodisplásica

Myelodysplastic Syndrome (MDS) is characterized by peripheral cytopenias, haematopoiesis ineffective, high levels of intramedullary apoptose and risk of transformation to AML. Various advances have performed for understanding the pathogenesis of MDS and various evidences that bone marrow failure occurs in MDS mediated by abnormal signalling of the innate immune system. The interferon regulatory factors (IRF-Interferon Regulatory Factor) is a family of transcription factors play a central role in regulating immune responses, differentiation and proliferation of hematopoietic cells, cell cycle regulation, apoptosis and oncogenesis. The aim of this study was to evaluate the profile of methylation and expression of IRFs gene in bone marrow cells patients with myelodysplastic syndrome. From samples of 119 patients diagnosed with MDS was evaluated of expression by real-time PCR and methylation by quantitative methylation specific PCR in real time of the nine family members of IRFs the expression of genes IRF2, IRF3, and IRF7 IRF8 were different between BM cells of MDS patients (p = 0.002, 0.002, 0.028 and 0.016, respectively). A higher level of expression of IRF1 was associated in patients with hypocellular bone marrow (p = 0.018). The expression of IRF 2 gene associated strong association with AR subtype (p = 0.002). The IRF3, IRF7 and IRF8 genes have been associated with patients with cytopenia (p = 0.028; 0.001; 0.008, respectively). Furthermore, methylation of IRF 1, IRF 2, IRF 3, IRF 5 , IRF 6 and IRF 8 was associated with higher risk characteristics in SMD, such as advanced forms, unfavorable karyotype, cytopenias, blasts above 5% and high risk categories established by the IPSS, IPSS-R and WPSS. Multivariate analysis revealed that patients with higher expression of IRF3 had higher overall survival (p = 0.001), whereas patients with a greater expression of IRF 5 had 5.4 more likely to progress to AML (p <0.001 95% CI 1.098- 26 829) and nine times more likely to come to death (p = 0.001, 95% CI 2.39 to 32.69). Ambiguously, patients with methylated IRF 5 had 4 times more than the patient's chance come to death (p = 0.041, 95% CI 1.066 to 20,192). In conclusion that the expression and methylation of IRFs can have great impact prognosis in this disease. The expression of IRF 3 is a favorable prognostic marker, as an expression and methylation of IRF5 are unfavorable prognostic markers in MDS.
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Type I interferons and interferon regulatory factors regulate TNF-related apoptosis-inducing ligand (TRAIL) in HIV-1-infected macrophages.

Type I interferons and interferon regulatory factors regulate TNF-related apoptosis-inducing ligand (TRAIL) in HIV-1-infected macrophages.

IRF-1 and IRF-3 have been shown to regulate TRAIL transcription in tumor cell lines [38–40]. More recently, overexpression of IRF-7 has been found to enhance TRAIL transcription in macrophages [41]. When we applied siRNA to knockdown IRF-1, IRF-3, or IRF-7 gene expression in human macrophages, the increase of TRAIL expression by HIV-1 infection was reduced by the IRF-1 and the IRF-7 knockdown, but not by the IRF-3 knockdown (Fig. 4G). This is, to the best of our knowledge, the first report of IRFs knockdown in HIV-1- infected macrophages. Knockdown of IRF-1 and IRF-7 reduced STAT1 phosphorylation, an essential component for type I IFNs responsiveness (Fig. 4E). However, type I IFNs-neutralizing antibodies did not completely block TRAIL upregulation in HIV-1-infected culture (Fig. 6D, E), suggesting the involvement of a type I IFNs-independent pathway in the induction of TRAIL. These type I IFNs-dependent and -independent mechanisms may work concomitantly in HIV-1-infected culture to induce TRAIL expression. Our analysis also found that IRF-5 gene expression could be induced upon HIV-1 infection in macrophages but in lower abundance. In addition, IRF-8 gene expression was not induced by HIV-1 infection but was expressed at a higher amount. Figure 4. siRNA knockdown of IRF-1 and IRF-7 reduces STAT1 phosphorylation and TRAIL expression in HIV-1-infected macrophages. Two days after HIV-1 infection, MDM were transfected with siRNA for IRF-1, -3, or -7. A. Forty-eight hours later, successful transfections were confirmed by Silencer FAM-labeled Negative Control #1 siRNA transfection indicator (green). Hoechst 33258 (nucleus marker, blue) was used to visualize the total cell number. B–D. Total RNA was collected 48 hours post-transfection and mRNA levels of IRF-1(B), -3(C), or -7(D) were determined by real-time RT-PCR. E. Ninety-six hours after transfection, p-STAT1 and total STAT1 were detected by Western blotting. b-actin was used as a loading control. F. TRAIL expression levels were determined by real-time RT-PCR. Results were normalized with GAPDH and shown as the fold change over non-specific siRNA control. G. Supernatants were tested for HIV-1 RTase activity. ** indicates p,0.01 when compared to control; # indicates p,0.05 when compared to HIV group with siRNA control; ## indicates p,0.01 when compared to HIV group with siRNA control. Data are representative of three donors.
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Distinct dictation of Japanese encephalitis virus-induced neuroinflammation and lethality via triggering TLR3 and TLR4 signal pathways.

Distinct dictation of Japanese encephalitis virus-induced neuroinflammation and lethality via triggering TLR3 and TLR4 signal pathways.

TLRs function as intermediates by interacting with products of viral replication, and transmitting signals to a cascade of adaptors and kinases that ultimately lead to the activation of transcription of cytokines and type I IFN genes. TLR3 recruits the adaptor molecule TRIF to induce type I IFN gene via interactions with TRAF3, TBK1, and IKKe, which, in turn, activate the latent transcription factors IRF-3 and IRF-7, whereas other TLRs associating with the adaptor protein MyD88 form a complex with TRAF6, IRAK1, and IRAK4 to activate kinases that regulate IRF-5 and IRF-7. Notably, TLR4 signal pathway uses both adaptor molecules MyD88 and TRIF to initiate the production of cytokine and type I IFN proteins. In viral infection, four TLRs, including TLR3, TLR7, TLR8 and TLR9, seem to play critical roles in the recognition of viral nucleic acid components, and TLR2 and TLR4 were shown to detect viral components such as envelope glycoproteins [22–26]. We have previously shown that JEV can modulate innate immune responses and subsequent adaptive responses in MyD88-dependent and independent path- ways [27], which indicate that JEV may be recognized by certain TLR signal pathways, thereby affecting the outcome of JEV- induced neurological diseases. Therefore, we aimed to determine whether each TLR signal pathway modulated neurological disease caused by JEV infection, using several TLR-deficient mice (TLR2, TLR3, TLR4, TLR7, TLR9). Surprisingly, among the tested TLR-deficient mouse strains we found a contrasting result in TLR3 2/2 and TLR4 2/2 mice, i.e. TLR3 2/2 mice were highly susceptible to JE, whereas TLR4 2/2 mice showed markedly enhanced resistance to JE. Subsequently, we investigated the pathologic feature, type I IFN innate and adaptive immunity of TLR3 2/2 and TLR4 2/2 mice during JE progression. TLR3 2/2 mice displayed severe neuroinflammatory reactions as well as enhanced BBB permeability by failure of the early control of viral replication, whereas TLR4 2/2 mice elicited the effective regula- tion of viral replication and subsequent inflammatory reaction by inducing potent type I IFN innate immune responses against JEV. Notably, our data revealed that TLR4 ablation provided potent type I IFN innate responses through enhanced induction of antiviral ISG genes by alternative activation of IRF-3 and NF-kB in myeloid-derived DCs and macrophages. Also, TLR4 2/2 mice showed an alteration of plasmacytoid DC subpopulation and CD4 +
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Opposing roles for interferon regulatory factor-3 (IRF-3) and type I interferon signaling during plague.

Opposing roles for interferon regulatory factor-3 (IRF-3) and type I interferon signaling during plague.

Type I interferons (IFN-I) are expressed by macrophages and epithelial cells as part of the first line of defense against infection, and the IFN-I receptor (IFNAR) is expressed by most cells [1]. IFN-I signaling following bacterial infection leads to the produc- tion of pro-inflammatory cytokines and chemokines and promotes apoptosis of infected cells [2]. In some cases, a pathologic role for IFN-I activation has also been described [3]. Interferon regulatory factor 3, IRF-3, is a major transcription factor that induces IFN-I following cytosolic detection of a pathogen [4]. Toll-like receptor (TLR) activation or other host pattern recognition receptors signal independent of the adaptor MyD88 to phosphorylate IRF-3 and activate IRF-3 dependent innate immune defenses [5]. Following phosphorylation, IRF-3P is found in the nucleus where it forms a complex with p300 which can act as a potent transcription factor, binding to interferon stimulated response elements (ISREs) on target genes, including Ifnb [6,7]. Secreted IFN-b binds IFNAR and signaling through STAT-1 and STAT-2 (signal transducers and activators of transcription) induces transcription of hundreds of ISRE-containing genes including many pro-inflammatory cytokines and chemokines. Further amplification of IFN-b expression occurs through an autocrine loop that requires IFNAR, IRF-3 and a second transcription factor IRF-7 and all three proteins play key roles in the expression of IFN-I [8].
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Involvement of DNA-PKcs in the type I IFN response to CpG-ODNs in conventional dendritic cells in TLR9-dependent or -independent manners.

Involvement of DNA-PKcs in the type I IFN response to CpG-ODNs in conventional dendritic cells in TLR9-dependent or -independent manners.

The Akt/mammalian target of rapamycin complex 1 (mTORC1) pathway is also suggested to be required for the type I IFN response to CpG-A in pDCs[5]. mTORC1 is an important downstream event of Akt, and can phosphorylate the ribosome 6 (S6) kinase (S6K), which in turn phosphorylates S6[6]. The mTORC1 inhibitor rapamycin was able to inhibit both the type I IFN and pro-inflammatory cytokine responses to CpG-ODNs[5]. Knockdown of S6K dimin- ished CpG-ODN-induced association of TLR9 with MyD88[5], indicating that Akt and S6K might act upstream of TLR9 in CpG-ODN signaling. Interestingly, chloroquine, which abol- ishes the activation of TLR9-dependent pro-inflammatory signaling, had no apparent inhibito- ry effect on Akt activation by CpG-ODN in THP1 macrophages[7]. Our results and others suggested that TLR9 was involved in Akt(S473) phosphorylation in bone marrow-derived mac- rophages (BMDMs) in response to CpG-ODNs [8, 9].
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Characterization of the in vitro cytokine response of phagocytes to mycobacteria

Characterization of the in vitro cytokine response of phagocytes to mycobacteria

Mycobacterium bovis BCG is the only vaccine currently available against TB. BCG is an attenuated strain of M. bovis (the etiological agent of cattle TB), derived from a virulent strain at the start of the last century, after more than 13 years of continuous in vitro passage (Andersen and Doherty, 2005). After almost a century from its discovery and more than 3 billion administrations, BCG is still in use today (Fine, 1995). However, BCG vaccination did not match all the expectations it evoked, because although it prevents disseminated TB in newborns (Colditz et al., 1995; Lanckriet et al., 1995; Murhekar et al., 1995; Trunz et al., 2006; Zodpey et al., 2005; Zodpey et al., 1998) its protection against the most common form of the disease, pulmonary TB in adults, can range anywhere from below zero to over 80% (Fine, 1995; Kaufmann, 2000; Sterne et al., 1998). This difference in protection is not well understood, however some aspects might account for it, such as the interference with the immune response to BCG vaccination by previous exposure to environmental mycobacteria (Brandt et al., 2002; Demangel et al., 2005; Roche et al., 1995); differences in BCG sub-strains (Behr, 2001a, b; Fine, 1995; Fine et al., 1994); deletion of protective antigens from BCG; failure of BCG to stimulate adequate immunity (Aagaard et al., 2009); differences in the route of administration (Skeiky and Sadoff, 2006), age of administration (Skeiky and Sadoff, 2006). Furthermore, the protection afforded by BCG is not life-long lasting, and it is believed that BCG is protective for only 10-20 years, which implies that protection wanes just as the risk of getting pulmonary TB increases (Sterne et al., 1998). The need to develop a new vaccine against TB is urgent and efforts are being made to do so. The most promising strategies for the generation of vaccine candidates are subunit protein vaccines, attenuated live vaccines or the combination of both. While attenuated live vaccines provide prolonged exposure of the host immune system to newly synthesized antigens, the advantage of subunit vaccines is the possibility that their efficacy may not be compromised by exposure to environmental mycobacteria or by prior BCG vaccination (Andersen, 2007; Andersen and Doherty, 2005).
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Fatores que determinam a produção de IL-12 em macrófagos murinos ativados por Bordetella...

Fatores que determinam a produção de IL-12 em macrófagos murinos ativados por Bordetella...

Os dímeros formados entre S2-S4 e S3-S4 unidos pela subunidade S5 funcionam como adesina, pois se ligam aos receptores celulares fixando a toxina à superfície das células do hospedeiro (células ciliadas do epitélio respiratório e macrófagos alveolares) mediando a entrada de S1 nessas células (CARNONETTI et al., 2007; KERR; MATTHEWS, 2000). No citosol, S1 catalisa a transferência da ADP-ribose do NAD para a subunidade  inibitória da proteína G (Gi) (KATADA; TAMURA; UI, 1983) e assim inibe a atividade dessa proteína (MATOO; CHERRY, 2005). Portanto, a Gi é incapaz de inibir a atividade da adenilato ciclase da célula do hospedeiro que continua ativada promovendo o aumento de AMPc intracelular, o qual interfere no processo metabólico celular e interrompe vias de sinalização. Dessa maneira, tem início os sintomas sistêmicos causados pela infecção com B. pertussis, como a leucocitose, hiperinsulinemia, hipoglicemia e sensibilidade histamínica (CARBONETTI, 2010; LOCHT; COUTTE; MIELCAREK, 2011).
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Mesenchymal Stem Cells (MSC) Regulate Activation of Granulocyte-Like Myeloid Derived Suppressor Cells (G-MDSC) in Chronic Myeloid Leukemia Patients.

Mesenchymal Stem Cells (MSC) Regulate Activation of Granulocyte-Like Myeloid Derived Suppressor Cells (G-MDSC) in Chronic Myeloid Leukemia Patients.

Chronic myeloid leukemia (CML) is a hematopoietic stem cell malignancy characterized by the t(9;22) chromosomal translocation that generates the BCR/ABL oncogene [1]. BCR-ABL tyro- sine kinase inhibitors (TKI) are able to induce remission in CML patients but not to eliminate leukemia stem cells (LSC), which can regenerate leukemia on drug discontinuation [2–4]. Understanding LSC regulation is critical to understand CML pathogenesis and to develop cura- tive strategies. Proliferation, survival and drug-resistance of leukemic cells are largely dependent on their interplay with the bone marrow (BM) microenvironment, in which mesenchymal stem cells (MSC) are important components. Indeed, the functional MSC behavior is essential to favor or impede LSC expansion and, for this reason, MSC represent a possible target for treat- ment of leukemias [5]. Since BM is a store of undifferentiated MSC, tumor cells precursors may affect the differentiation of MSC in the tumor niche suggesting a deep cross-talk between LSC and MSC [6]. Interestingly, despite MSC from CML patients do not express BCR–ABL [7], recent studies have reported an altered regulation of MSC in CML, showing that changes in BM microenvironmental function suppress normal hematopoietic stem cells (HSC) and provide a selective advantage to LSC[8]. Into the tumor milieu, MSC also play an important role for their immunosuppressive ability that can interfere with the immune recognition of tumor cells. Indeed, they produce and release immunoregulatory factors, including transforming growth factor β (TGF-β), prostaglandin E2 (PGE2), tumor necrosis factor α (TNFα), indolamine 2,3-dioxygenase (IDO), hemeoxygenase (HO), nitric oxidase synthase 2 (NOS2), arginase 1–2 (ARG1-2) and IL10 [5, 9–11]. MSC express programmed death ligand 1 (PD-L1) that after its engagement with PD-1 expressed on T lymphocytes leads to the inhibition of T cell activation and proliferation with an inefficient immune response [12].
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The battle between rotavirus and its host for control of the interferon signaling pathway.

The battle between rotavirus and its host for control of the interferon signaling pathway.

TLR3, TLR7, and TLR9 have been implicated in stimulating innate responses to rotavirus infection, although more definitive studies on these topics are required [21–24]. Unlike the RLRs, the role of specific signaling components downstream of TLRs including the adaptors MyD88 and TRIF (Toll/IL-1 receptor domain-containing adaptor inducing IFN-b) during infection has not been well studied in relevant cell types. TLR7 and/or TLR9 seem to have roles in rotavirus recognition in primary human plasmacytoid dendritic cells (pDCs), a lineage that is only minimally permissive to rotavirus replication [21]. pDCs are a major source of systemic IFN and an important link between innate and adaptive antiviral immune responses [25]. Both replication-competent and inactivated rotaviruses efficiently acti- vate an IFN response in pDCs [21]. The PAMP responsible for this activation appears to be viral genomic dsRNA interacting with TLR7 and/or TLR9 [21]. Although dsRNA is widely recognized as a potent PAMP and purified rotavirus genomic dsRNA induces the expression of IFN-b and other cytokines [26,27], the rotavirus replication cycle produces protein components that are likely to minimize host cell interaction with the dsRNA genome (e.g., sequestration within the viral particle). Thus, the source and type of RNA recognized by TLRs, as well as whether this interaction involves intra- or extra-cellular TLRs in the infected cell, remain unclear. Limited studies on the role of TLRs during rotavirus infection in the mouse model of infection have noted that MyD88 (mediating TLR7, 8 activation), TRIF (TLR3), or TLR3 are not required for IFN induction in intestinal epithelial cells (IECs) or myeloid DCs (mDCs) following infection with either RRV or murine rotavirus [17,22]. In contrast, another study reported that age-dependent TLR3 expression is associated with limited rotavirus shedding and type III IFN synthesis, but these effects were specific to adult mice [24]. Further studies are clearly needed to evaluate the role of TLR3 in rotavirus infection, particularly in the primary target, the non-adult host.
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Characterization of complexity in engineering projects

Characterization of complexity in engineering projects

When mentioning Scope, the respondents are guided by perceptions of great scale or great specificity in relation to the work to be delivered by the project. In this sense, although a complex system does not necessarily have thousands of parts (Rensburg, 2012), Baccarini (1996) suggests that complexity in projects can be interpreted and measured in terms of differentiation (numerous parts), as well as Yugue & Maximiano (2013) warn that scope is one of the keys to dealing with complexity. In addition, multiplicity (quantity of potentially interacting elements) is one of the properties that determine the complexity of an environment (Sargut & McGrath, 2011; Tarride, 2013). Therefore, this finding is consistent with the researched literature.
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en 0104 530X gp 0104 530X2957 16

en 0104 530X gp 0104 530X2957 16

Palavras-chave: Projetos complexos; Teoria da Complexidade; Teoria da Representação Social; Evocação de palavras. Abstract: The complexity of the projects has increased, boosting the demand in modern project management for new knowledge, tools, techniques and work models. However, the scientiic community still seeks a deinition for the complex project construct and the factors that characterize it. Therefore, the objective of this qualitative and descriptive study was to identify the factors that characterize the complexity in the vision of engineering project management professionals and from that, to propose a deinition for a complex project. This characterization was based on the perception of 132 respondents, captured through the word evocation technique; treated and analyzed by the Vèrges technique with the support of Social Representation Theory and Complexity Theory. As a result, the central nucleus of the social representation that characterizes a complex project in the view of the professionals of the engineering area was constituted in descending order by: stakeholders, dificulty, risks, technology, large, scope, multidisciplinary and long. It is observed that complex projects are seen as a superlative system, in terms of quantity and quality of constituents, and stakeholders management gains protagonism.
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Down-regulation of 5-HT1B and 5-HT1D receptors inhibits proliferation, clonogenicity and invasion of human pancreatic cancer cells.

Down-regulation of 5-HT1B and 5-HT1D receptors inhibits proliferation, clonogenicity and invasion of human pancreatic cancer cells.

On the other hand, the uPAR-mediated activity requires integrin-dependent signaling [75,76]. The integrin family of cell adhesion molecules facilitates the penetration and invasion of the cancer cell to the surrounding extracellular matrices [27]. In pancreatic BxPC3 cells, the blocking of the over-expressed b1 integrin was found to decrease the activation of uPA/MMP-2 with subsequent decrease in metastasis [46]. b1 integrin is proposed as an emerging target that limits the metastasis of the tumors in-vivo [77], since it plays a profound role in cancer initiation, tumor growth progression and invasion/metastasis, through cell binding to ECM [78,79]. Moreover, b1 integrin expression is known to induce Src activity, which is associated with shorter patient survivals, making both b1 integrin and Src appealing targets for cancer therapy [80]. Src is one of the tyrosine kinases that plays a critical role in signal transduction associated with cell–extracellular matrix interactions, migration and adhesion [81]. Interestingly, Src inhibitors have shown a significant inhibition of the tumor growth in a subset of human pancreatic tumor xenografts [82]. In addition, recruitment of Focal adhesion kinase (FAK)/Src complex mediates and regulates the signaling events downstream of integrin-dependent pathway [27]. The cytoplasmic protein tyrosine kinase, FAK, is involved in integrin-mediated signal transduction and plays an important role in the control of cell spreading, migration, and survival [83]. Src/FAK mutually regulates the activity of each other and promotes normal and cancer cell migration by regulating focal adhesion formation and turnover through multiple signaling connections [41]. Enhanced FAK signaling was also connected to elevated uPA expression, directly contributing to the proliferation, invasion and metastatic phenotype [84]. It was documented that the cells expressing an activated FAK–Src signaling alter the surrounding stromal environment, facilitating breakdown of cell-cell adhesion, in- creased cell-matrix– and focal–adhesions and tissue invasion. Accordingly, inhibition of Src/FAK activity leads to restoration of cell-cell adhesion and inhibits cell migration and invasion [41]. In the current study, we demonstrated the potential inhibition of b1 integrin protein and gene expression and the inhibition of Src/ FAK activity after silencing of 5-HT 1B and 5-HT 1D receptors in
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The comparison of the structure and microhardness of the tool steel C90 and HS 6-5-2 remelted with the electric arc

The comparison of the structure and microhardness of the tool steel C90 and HS 6-5-2 remelted with the electric arc

The tool steels consistute a very important group of materials used for the production, not only tools, but also machine ele- ments, that need to have the increased strength, for example the high-speed steels are used on the rolling bearing operating in high temperatures [1]. Modern technologies such as: laser treatment, electron treatment, CVD, PVD methods, give the possibility of forming the structure of the surface layer of steels providing the demaded properties. The economic factors direct research in using the plasma of the electric arc for shaping the surface layer of the machine elements and tools. Advantages of that method are the possibilities of receiving wider treated areas with one stream of the heat in comparison with the laser technologies or electron
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Distinct Upstream Role of Type I IFN Signaling in Hematopoietic Stem Cell-Derived and Epithelial Resident Cells for Concerted Recruitment of Ly-6Chi Monocytes and NK Cells via CCL2-CCL3 Cascade.

Distinct Upstream Role of Type I IFN Signaling in Hematopoietic Stem Cell-Derived and Epithelial Resident Cells for Concerted Recruitment of Ly-6Chi Monocytes and NK Cells via CCL2-CCL3 Cascade.

models demonstrate that some leuko- cytes derived from the HSC lineage play a dominant role in the recruitment of CD11b + Ly-6C hi monocytes into vaginal tissues as well as iliac LNs because only IFNAR KO mice reconstituted by WT BM cells (WT-KO) showed comparable recruitment of CD11b + Ly-6C hi monocytes into vaginal and iliac LN tissues to that of WT recipients of WT BM cells (WT-WT). This result contrasts starkly with the fact that IFN-I signals on corneal resident cells play an impor- tant role in recruiting CD11b + Ly-6C hi monocytes in the corneal area [13], but is in line with a report that IFN-I signaling on the hematopoietic cell lineage plays a dominant role in leukocyte recruitment into inflammatory lung tissues after influenza infection [29]. Supportively, CCL2 production in vaginal tissues of WT-KO BM chimeric model gradually increased up to 24 h pi, after which CCL2 level decreased. This implies that recruitment of CD11b + Ly-6C hi monocytes may be governed by other chemokines produced from resident cells after 24 h pi or that CCL2 pool produced up to 24 h is sufficient to recruit major CD11b + Ly-6C hi monocytes. The former
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Three novel downstream promoter elements regulate MHC class I promoter activity in mammalian cells.

Three novel downstream promoter elements regulate MHC class I promoter activity in mammalian cells.

Regulatory mechanisms governing transcriptional activation are generally thought to be limited to the recruitment of transcription factors to upstream enhancer and silencer DNA binding sites, which in turn target a set of general transcription factors and co- activators to a core promoter which serves only as a scaffold for transcriptional machinery recruitment. However, it is now evident that the core promoter plays an active role in integrating signaling pathways [41,49,50]. The mechanisms that contribute to core promoter element specificity, linked with differential transcription factor usage create a more complex and dynamic layer of regulation mediated by the core promoter itself [26]. The MHC class I core promoter provides a clear example of the active role that core promoters play in integrating regulatory signals. What distinguishes the MHC class I promoter from many other previously studied promoters is the number of converging synergistic and competing signaling pathways that must be integrated to ensure continued immune surveillance in the face of intra-cellular pathogens. In this study, we have identified three novel downstream elements that regulate MHC class I gene expression by integrating regulatory signals on specific transcrip- tion start sites. We suspect once other complex mammalian promoters are examined carefully, additional novel regulatory factors and mechanisms will be revealed that will further our understanding of this intricate process.
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The coxsackievirus B 3C protease cleaves MAVS and TRIF to attenuate host type I interferon and apoptotic signaling.

The coxsackievirus B 3C protease cleaves MAVS and TRIF to attenuate host type I interferon and apoptotic signaling.

and either full-length or C-terminal TRIF (Figure 6D and 6E) suggesting that the interaction between TRIF and 3C pro is diminished following cleavage. Interestingly, we observed the appearance of cleavage fragments of both HA-NT-Flag and HA- CT-Flag when coexpressed with wild-type 3C pro (Figure 6D). To further define the extent of 3C pro -mediated proteolysis of the N- and C-terminal regions of TRIF, we coexpressed dually HA- and Flag-tagged constructs of TRIF (described in Figure 6C) and wild-type or C147A EGFP-3C pro and subjected lysates to dual- color (700 nm and 800 nm) immunoblot analysis using a LI-COR Odyssey infrared imaging system and antibodies specific for HA and Flag. This technique could therefore allow for the detection of a variety of TRIF cleavage fragments simultaneously. We found that expression of wild-type 3C pro (but not the C147A mutant) induced the cleavage of both the N- and C-termini of TRIF (Figure 7A). In contrast, we observed no cleavage of the TIR domain (Figure 7A). Additionally, our data indicate that the C-terminus of TRIF is cleaved more abundantly than the N-terminus as we observed a marked decrease in the expression of full-length HA-CT-Flag and the appearance of several HA- or Flag-tag-positive cleavage products induced by 3C pro overexpres- sion (Figure 7A).
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SOCIAL ECONOMY – A FORM OF INCLUSION AND OF ''REACTIVATING'' OF LABOR IN THE CONTEXT OF THE CURRENT CRISIS

SOCIAL ECONOMY – A FORM OF INCLUSION AND OF ''REACTIVATING'' OF LABOR IN THE CONTEXT OF THE CURRENT CRISIS

)n the context of the cohesion policy, solidarity must represent a support for development . For that purpose, solidarity can be seen as a help for self‐help and its success depends a great deal on the capacity and the training of the people to whom the support of making maximum profit out of these addresses to. This support does not mean exclusively financial support, although it is necessary and important but, of all things, it means an exchange of experiences and cooperation, the development of capacity through training, open discussions with the interested factors and last but not least a critic, but a constructive dialogue between the various levels of government: European, national, regional, local. )n other words, a functional labor market should represent a catalyst for the general objective of the European Union – social and economical cohesion – because it has in view the connections with the different markets of the services and of the goods and generates the necessary income for supporting the participation of the individuals, bringing them together, placing them in collaborations. )n this context, the starting points for promoting the inclusion through the activities of social economy have in view: adapting the institutional environment, developing the public‐private partnership, developing the social dialogue between players, investments in the human capital and supporting the exchange of good practices within the European Union.
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Immunodetection of myeloid and plasmacytoid dendritic cells in mammary carcinomas of female dogs

Immunodetection of myeloid and plasmacytoid dendritic cells in mammary carcinomas of female dogs

Dendritic cells have attracted great interest from researchers as they may be used as targets of tumor immune evasion mechanisms. The main objective of this study was to evaluate the relationship between the dendritic cells (DCs) subpopulation in simple type mammary carcinomas in female dogs. Two groups of samples were used: the control group consisted of 18 samples of mammary tissue without changes and the tumor group with 26 simple type mammary carcinomas. In these groups, we evaluated the immunodetection of immature and mature myeloid DCs, plasmacytoid DCs and MHC-II. In mammary tumor, mature myeloid DCs predominated in the peritumoral region, while immature myeloid DCs and plasmacytoid DCs were evident in the intratumoral region. Immunostaining of MHC-II was visualized in mammary acini (control group), in tumor cells and inflammatory infil- tration associated with tumors. The comparison between the control and tumor groups showed a statistically significant difference between immature myeloid DCs, mature mye- loid DCs and plasmacytoid DCs. The immunodetection of MHC-II was not significant when comparing the groups. The predominance of immature DCs in the tumor group is possibly related to an inefficient immune response, promoting the development and survival of tu- mor cells. The presence of plasmacytoid DCs in the same group suggests a worse prognosis for female dogs with mammary tumors. Therefore, the ability of differentiation of canine dendritic cells could be influenced by neoplastic cells and by the tumor microenvironment. INDEX TERMS: Dogs, antigen presenting cells, immune evasion, immunohistochemistry, mammary tumor.
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Morbillivirus v proteins exhibit multiple mechanisms to block type 1 and type 2 interferon signalling pathways.

Morbillivirus v proteins exhibit multiple mechanisms to block type 1 and type 2 interferon signalling pathways.

ability to bind to host proteins from different species. However, the host proteins involved in these interactions (STAT1/2, Jak1, Tyk2) are all highly conserved across many species, and we have previously shown that RPV (which causes disease only in cattle, buffalo and related artiodactylates) is highly effective at blocking IFN action in human and monkey as well as bovine cells [23]. We have carried out the studies here in primate cells, choosing Vero cells for transfection and some other studies because they are known not to produce their own type 1 IFN, and support the replication of all morbilliviruses, and A549 cells because they have good levels of endogenous STAT1 and STAT2, making immu- nofluorescence visualisation of STAT activation better than in the Vero cells. Although we used only one wild type strain of each virus, the activities of these viruses and their proteins in a range of assays has shown that there are several distinct mechanisms employed by the members of this genus to block IFN action, and that they act in synergy to provide maximal ability of the virus to replicate in the face of host innate defences. We observed that V proteins from all four viruses were effective blockers of type I IFN- induced gene transcription using a reporter gene assay, although this was not true of V proteins from two cell culture-attenuated vaccine strains, MeV-Edm and CDV-Ond. However, there were striking differences in the abilities of the V proteins to block type II IFN-induced gene transcription. RPV V was the most effective, and MeV V and CDV V the least, with PPRV V being intermediate. Again the MeV and CDV vaccine strain V proteins were worse than those from their respective unattenuated strains, while there was no significant difference between the V proteins of virulent and vaccine strains of RPV. Similarly, while all the wild- type V proteins were effective in blocking type I IFN-induced STAT1/2 phosphorylation, there was a big variation in their ability to block type II IFN. These data strongly suggested that the mechanism(s) by which the viruses block type I and type II IFN signalling are different.
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